U.S. GEOLOGICAL SURVEY CIRCULAR 1096 

Statistics of Petroleum Exploration in the 

Caribbean, Latin America, Western Europe, 

the Middle East, Africa, Non-Communist 

Asia, and the Southwestern Pacific 

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Statistics of Petroleum Exploration in the 

Caribbean, Latin America, Western Europe, 

the Middle East, Africa, Non-Communist 

Asia, and the Southwestern Pacific 

By EMIL D. ATTANASI and DAVID H. ROOT 

A summary of the geographic location, amount, and results of 

petroleum exploration, including an atlas showing explored and 

delineated prospective areas through 1990. This report updates 

and expands Circular 981 

U.S. GEOLOGICAL SURVEY CIRCULAR 1096 
U.S. DEPARTMENT OF THE INTERIOR 

BRUCE BABBITI, Secretary 

U.S. GEOLOGICAL SURVEY 

Dallas L. Peck, Director 

Any use of trade, product, or firm names 

in this publication is for descriptive purposes only 

and does not imply endorsement by the U.S. Government 

UNITED STATES GOVERNMENT PRINTING OFFICE: 1993 

Free on application to 

U.S. Geological Survey, Map Distribution 

Box 25286, MS 306, Federal Center 

Denver, CO 80225 

Library of Congress Cataloging in Publication Data 

Attanasi, E.D. 

Statistics of petroleum exploration in the Caribbean, Latin America, Western 

Europe, the Middle East, Africa, non-Communist Asia, and the southwestern Pacific I by Emil D. Attanasi and David H. Root. 

p. em. - (U.S. Geological Survey circular ; 1096) 

Rev. ed. of: Statistics of petroleum exploration in the non-Communist world 

outside the United States and Canada I David H. Root, Emil D. Attanasi, 

and Robert M. Turner. 

Includes bibliographical references. 

Supt. of Docs. no.: I 19.4/2:1096 

1. Petroleum-Prospecting-Statistics. 2. Oil fields-Statistics. I. Root, 

David H. II. Title. Ill. Series. 

TN271 . P4R66 1993 

553.2'8-dc20 92-41228 

CIP 
CONTENTS 

Abstract 1 

Introduction 1 

Acknowledgments 2 

Exploration and Discoveries Since 1950 2 

Exploration 2 

Discoveries 3 

Size Distribution of Petroleum Provinces 4 

Study Area 4 

Mexico 5 

South America 5 

Western Europe 5 

Middle East 5 

Africa 5 

Non-Communist Asia 5 

Southwestern Pacific 6 

Delineated Prospective Area 6 

Explored and Delineated Prospective Areas 6 

Delineated Prospective Area by Region-Exploration and Discovery 6 

Other Applications of Delineated Prospective Area 7 

Growth in Estimates of Field Sizes 8 

Summary and Conclusions 8 

References Cited 9 

FIGURES 

[Figures follow Tables] 

1, 2. Time profiles for South America, Western Europe, the Middle East, Africa, 

non-Communist Asia, and the southwestern Pacific, showing the cumulative 

number of wildcat wells drilled, 1950-90: 

1. Offshore and onshore 34 

2. Offshore 35 

3. Time profile of annual wildcat drilling in the study area and U.S. refiners' 

crude-oil acquisition price, 1968-90 36 

4. Graphs showing oil and gas discovery rates for the study area averaged for 

5-year periods, 1951-85, and the 4-year period, 1986-89 36 

5-7. Graphs showing oil and gas discovery rates for South America, Western 

Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific, averaged for 5-year periods, 1951-85, and the 4-year period, 

1986-89: 

5. Oil discovered per year 38 

6. Oil discovered per wildcat well 39 

7. Gas discovered per year 40 

8. Graph showing frequency distribution of sizes of the 99 significant petroleum 

provinces identified through 1990 in the study area 41 

Contents Ill 
IV Contents 

9-12. Graphs showing the historical sequence by year of first discovery in each significant petroleum province and the magnitude of total discoveries through 

1990 in each province in9. South America 42 

10. Western Europe 43 

11. Africa 44 

12. Non-Communist Asia 45 

13. Graphs showing growth in delineated prospective and explored areas and oil 

discovered in the study area through 1990 46 

14. Graphs showing growth in prospective and explored areas delineated by drilling through 1990 for South America, Western Europe, the Middle East, 

Mrica, non-Communist Asia, and the southwestern Pacific 47 

15. Graphs showing oil discovered through 1990 ordered by the year its field location was classified as part of the delineated prospective area for South America, Western Europe, the Middle East, Africa, non-Communist Asia, and the 

southwestern Pacific 48 

16. Graphs showing growth in fields discovered by 1980 for five regions 49 

17-54. Maps and graphs of delineated prospective areas, explored areas, and known 

petroleum provinces of17. The Caribbean 52 

18. Central America 54 

19. Guyana, Suriname, and French Guiana 56 

20. Chile 58 

21. Argentina, Uruguay, and Paraguay 60 

22. Ecuador 62 

23. Colombia 64 

24. Peru 66 

25. Venezuela and Trinidad and Tobago 68 

26. Bolivia 70 

27. Brazil 72 

28. The northern part of Western Europe 74 

29. The middle and southern parts of Western Europe 78 

30. Turkey and Cyprus 80 

31. The Arabian Peninsula 82 

32. Syria, Lebanon, Israel, and Jordan 84 

33. Iraq 86 

34. Iran 88 

35. Senegal, The Gambia, Guinea-Bissau, Guinea, Sierra Leone, Liberia, 

Ivory Coast, Ghana, Togo, Benin, and Cape Verde 90 

36. Ethiopia, Djibouti, Somalia, and Kenya 92 

37. Angola 94 

38. Nigeria 96 

39. Tunisia and Libya 98 

40. Morocco and Algeria 100 

41. Egypt 102 

42. Tanzania, Malawi, Mozambique, Burundi, and Rwanda 104 

43. Swaziland, Namibia, Lesotho, Zimbabwe, Zambia, Botswana, and South 

Africa 106 

44. Cameroon, Central African Republic, Equatorial Guinea, Gabon, Sao 

Tome and Principe, Congo, and Zaire 108 

45. Western Sahara, Mauritania, Mali, Burkina Faso (formerly Upper Volta), 

Niger, Chad, Sudan, and Uganda 110 

46. Madagascar, Mauritius, Seychelles, and Comoros 112 

47. Mghanistan and Pakistan 114 
17-54. Maps and graphs of delineated prospective areas, explored areas, and known 

petroleum provinces of48. Maldives, India, Bangladesh, Myanmar (formerly Burma), Thailand, Sri 

Lanka, Nepal, and Bhutan 116 

49. Taiwan, Philippines, Japan, and South Korea 118 

50. Indonesia 120 

51. Malaysia, Brunei, and Singapore 122 

52. Papua New Guinea and Oceania 124 

53. New Zealand 126 

54. Australia and New Caledonia 128 

TABLES 

[Tables follow References Cited] 

1. Exploration wells by year, 1950-89, for the Caribbean, Latin America, Western 

Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific 12 

2. Wildcat wells by year, 1951-90, for the Caribbean, Latin America, Western 

Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific 20 

3. Regional distribution of total and offshore wildcat wells drilled through 1990 and 

discoveries in terms of estimated ultimate recovery 28 

4. Year of first discovery and cumulative recoverable oil and gas discoveries through 

1990 in the 99 significant petroleum provinces in the study area 29 

5. Regional distribution of land area, delineated prospective area, explored area, and 

rate of addition to prospective area 32 

6. Estimates of ultimate recovery of cumulative oil discovered by region from 1900 to 

1980 as recorded by Petroconsultants in the first tapes issued in 1981 , 1984, 1987, 

and 1990 32 

Contents V 

Statistics of Petroleum Exploration in the 

Caribbean, Latin America, Western Europe, the 

Middle East, Africa, Non-Communist Asia, and the 

Southwestern Pacific 

By Emil D. Attanasi and David H. Root 

Abstract 

This circular presents a summary of the geographic 

location, amount, and results of petroleum exploration, 

including an atlas showing explored and delineated prospective areas through 1990. The data show that wildcat 

well drilling has continued through the last decade to 

expand the prospective area by about 40,000 to 50,000 

square miles per year. However, the area delineated by 

1970, which represents only about one-third of the prospective area delineated to date, contains about 80 percent of the oil discovered to date. This discovery distribution suggests that, from an overall prospective, the 

industry was successful in delineating the most productive 

areas early. The price increases of the 1970's and 1980's 

allowed the commercial exploration and development of 

fields in high-cost areas, such as the North Sea and 

Campos Basin, Brazil. Data on natural-gas discoveries also 

indicate that gas will be supplying an increasing share of 

the worldwide energy market. 

The size distribution of petroleum provinces is highly 

skewed. The skewed distribution and the stability in 

province size orderings suggest that intense exploration in 

identified provinces will not change the distribution of oil 

within the study area. Although evidence of the fieldgrowth phenomenon outside the United States and Canada is presented, the data are not yet reliable enough for 

projecting future growth. The field-growth phenomenon 

implies not only that recent discoveries are substantially 

understated, but that field growth could become the 

dominant source of additions to proved reserves in the 

future. 

INTRODUCTION 

The intention of this report is to summarize, for the 

general reader, basic statistics of petroleum exploration in 

the areas outside the United States and Canada and outside 

former and current Communist areas of Eastern Europe and 

Manuscript approved for publication September 16, 1992. 

Asia. This report updates and expands our original report 

entitled "Statistics of Petroleum Exploration in the NonCommunist World Outside the United States and Canada," 

U.S. Geological Survey Circular 981 (Root and others, 

1987). During the last 40 years, even though the United 

States and Canada accounted for most of the world's 

drilling, most of the oil was discovered outside of these 

areas. U.S. and Canadian petroleum industries are mature, 

and domestic exploration potential is better known than that 

in the rest of the world. This report, therefore, focuses on 

areas outside of the United States and Canada. The unavailability of reliable data on exploratory wells and oil and gas 

fields for the republics of the former Soviet Union, formerly 

Communist Eastern European countries, and Communist 

Asian countries necessitated that these countries still be 

excluded from this study. As private exploration is permitted, perhaps historical exploration data and the new data 

from ongoing exploration activities will be assembled and 

made available to researchers. Hereafter, we refer to the 

study area as the areas outside the United States and Canada 

and outside the areas formerly or currently Communist in 

Eastern Europe and Asia. 

Where possible, the revisions to most of the original 

data series published in U.S. Geological Survey Circular 

981 have been extended through 1990. The series that 

related to the crew months of geologic and geophysical 

activity was discontinued. The data had come from the 

annual foreign developments issues of the Bulletin of the 

American Association of Petroleum Geologists (AAPG). 

This annual collection of regional and individual country 

reports did not cover all areas having exploration, and the 

crew-month data were frequently not accurately reported. In 

the absence of wildcat drilling, crew-month activity provides evidence that areas have been screened and also 

indicates the intensity of predrilling evaluation. In recent 

years, the AAPG report writers focused more on describing 

results of certain strategic exploratory wells rather than on 

presenting a full accounting of geologic and geophysical 

Introduction 
activity and exploration wells. Moreover, because of the 

changes in technology during the last 30 years, annual 

amounts of crew-month activity are not comparable in terms 

of both cost and the information value of data collected. 

Exploration well data are from AAPG; some were 

published in the annual foreign developments issues of the 

AAPG Bulletin, and some were published in the International Petroleum Encyclopedia (Penn Well Publishing 

Company, 1986-90). Wildcat well data were taken from the 

well computer tape released by Petroconsultants S.A., 

Geneva, in January 1991. Reported discoveries of crude oil 

and natural gas are from the field tape received in January 

1991 from Petroconsultants. The field data were augmented 

by additional data from W.D. Dietzman (retired) and Gary 

Long, both of the Energy Information Administration 

Office, U.S. Department of Energy, Dallas, Tex. (written 

commun., 1990). The data were subjected to additional 

validation tests, and corrections were then made as necessary. Unless otherwise stated, all field-size estimates used 

here are based on this data set. In this report, oil and gas 

discovered were classified as offshore only when the field 

containing the resource was entirely offshore. 

In addition to updating most of the original data 

presented in U.S. Geological Survey Circular 981, this 

report presents new topics and data series. The field-growth 

(reserve-appreciation) phenomenon is discussed, and 

natural-gas discovery data are also presented for the study 

area. Because of product distribution problems and a 

limited international market, natural gas has not been an 

economic commodity for many countries. However, the 

share of natural gas in the overall worldwide energy market 

is beginning to increase. 

Even with some data deficiencies, the information 

provides a summary, based on the historical results of 

exploration, of available knowledge on the petroleum 

potential of a country. The assemblage of this information is 

time consuming, costly, and beyond the reach of individual 

analysts, many private organizations, and the public. By 

placing this information in the public domain, we hope it 

will be of assistance to those responsible for planning or 

evaluating exploration programs in industry, government, 

and international agencies. 

This report summarizes basic statistics of petroleum 

exploration drilling and discovery. The discussion initially 

focuses on numbers of exploration wells and wildcat wells 

drilled each year by country (tables 1 and 2). Graphs (figs. 

1-15) show aggregate and regional trends in exploration 

and oil and gas discoveries, as well as the regional distribution of petroleum provinces. The phenomenon of growth 

in field-size estimates over time is discussed and shown to 

lead to substantial revisions in the interpretation of historical discovery data (fig. 16). Maps show the area that has 

been drilled, and accompanying graphs (figs. 17-54) show 

expansion of the areas explored and trends in the amounts of 

oil discovered in newly drilled areas. 

Acknowledgments 

The authors gratefully acknowledge the contribution 

of Vaughn Eisler, of the U.S. Geological Survey, who 

applied the ARC/INFO software package to display the 

maps that show the delineated prospective and explored 

areas. 

EXPLORATION AND DISCOVERIES SINCE 1950 

Exploration 

Exploration and wildcat well data are summarized in 

tables 1 and 2. The exploration well data for 1950-80 

represent the compilations presented in the regional reports 

by various writers published in the annual foreign developments issues of the AAPG Bulletin. Exploration well data 

for 1980-85 were taken from both the annual summary of 

the AAPG data and the compilations of the AAPG data 

published by the International Petroleum Encyclopedia. 

Data for 1985-89 are from the International Petroleum 

Encyclopedia. AAPG exploration wells include new-field 

wildcat wells, new-pool wildcat wells, extension wells, and 

deeper pool tests. The AAPG data are compiled from 

summaries that provide aggregate numbers of exploration 

wells spudded or completed during the year. These reports 

do not generally contain information about individual wells. 

Wildcat well data are from the Petroconsultants well 

tape released in January 1991. The Petroconsultants wildcat 

wells summarized in table 2 are only new-field wildcat 

wells. The Petroconsultants data included longitude and 

latitude, well depth, and formations penetrated. 

Because India, Iraq, and several other countries 

regarded the petroleum industry as vital to national security, 

information about drilling was regarded as a state secret, 

and dissemination of such information was prohibited. 

Drilling levels from these countries may be substantially 

understated. 

U.S. and Canadian exploration and wildcat drilling 

have typically accounted for 70 to 90 percent of drilling 

outside of Eastern Europe and Communist Asia. For example, in 1989 the AAPG reported that the United States and 

Canada had 3,056 wildcat wells, and the Petroconsultants 

data show wildcat drilling in the study area to be 1 ,006. For 

exploration wells, comparable numbers are 8,257 and 

1 ,354, respectively. Comparison of absolute drilling levels 

is misleading. A significant proportion of wildcat and 

exploration drilling done outside the United States and 

Canada is directed at testing new plays and provinces, 

whereas nearly all of U.S. and Canadian drilling is in 

productive plays and provinces that are mature from an 

exploration standpoint. 

The time profile in the growth of cumulative wildcat 

wells drilled since 1950 is presented on a regional basis in 

figure 1. The most wildcat wells in the study area were 

2 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
drilled in Western Europe; the number of wildcat wells 

decreases for South America, Africa, non-Communist Asia, 

the southwestern Pacific, and the Middle East. The gross 

number of cumulative wildcat wells drilled may not accurately measure the level of exploration effort or the degree 

to which an area has been evaluated. Many of the wildcat 

wells in Western Europe were drilled to find small onshore 

oil and gas fields that could be commercially developed 

because of Europe's advanced infrastructure and established 

markets. In comparisons of gross drilling statistics, these 

wells are given the same weight as the expensive high-risk 

wells drilled in the North Sea. Alternatively, information 

gathered from a few wildcat wells may allow the reconstruction of geologic history, which may indicate that the 

province is too immature geochemically to have generated 

hydrocarbons. There may be little further drilling. Although 

drilling in such an area appears to be sparse, the area may 

actually be considered to be evaluated. 

Regional levels of cumulative offshore wells drilled 

in the study area are shown in figure 2. Even though in 1990 

offshore wells represented 43 percent of the annual wildcat 

drilling, on a cumulative basis, offshore wildcats accounted 

for just under a quarter of cumulative wildcats in the study 

area. In Western Europe, offshore discoveries accounted for 

90 percent of total crude oil discoveries, while, for nonCommunist Asia and the southwestern Pacific, they 

accounted for 64 and 72 percent of total discoveries. Table 

3 presents data showing the regional distribution of cumulative wildcat wells and discoveries. Offshore drilling and 

production costs are typically higher than costs for similar 

depths and fields onshore. The growth in offshore exploration in many instances reflects the perceived superiority of 

the offshore prospects to remaining onshore prospects in 

terms of field size. In other instances, lower infrastructure 

costs are associated with offshore field development when 

compared to those required for development of remote 

onshore prospects. 

The level of annual wildcat drilling for the study area 

increased very little relative to the crude-oil price increases 

in the 1970's (fig. 3). Outside of the members of the 

Organization of Petroleum Exporting Countries (OPEC), 

the price increases in the 1970's allowed drilling and 

development in high-cost areas such as the North Sea and 

the Campos Basin in deep water off Brazil. For the study 

area, in 1970 about one-third of the wildcat wells were 

offshore. In 1980, offshore wildcat wells accounted for 46 

percent of the wildcats drilled in the study area. By the 

1981-85 period, about half of the average annual oil 

discovered in the study area outside of the Middle East was 

offshore. 

Discoveries 

For the study area, annual oil discovery rate, oil 

discovery rate per well, and the annual gas discovery rate in 

5-year intervals from year-end 1950 to year-end 1985 are 

presented in figures 4A, 4B, and 4C, respectively. Because 

there are probably unreported 1990 discoveries, the discovery rate for the last interval runs from 1986 to 1989. The 

annual oil discovery rate (fig. 4A) shows that, from 1955 to 

1985, offshore discoveries accounted for at least one-third 

of the annual average oil discovered in the study area. The 

oil discovery rate per well (fig. 4B) for the study area has 

declined from over 50 million barrels of oil per well in the 

early 1950's to 7 million barrels in the early 1980's. 

Through the late 1970's, the discovery rate was over about 

20 billion barrels of oil per year, and about half the oil was 

discovered offshore. Figure 4C shows that at least half of 

the natural gas reported discovered since the 1970's was 

offshore. However, reported quantities of gas discoveries 

are probably incomplete or understated because gas is still 

not commercially developable in many countries. 

The regional annual oil discovery rates and oil discovery rates per well are shown in figures 5 and 6. The 

Middle East dominates average annual oil discovered and 

oil-per-well discovery rates. In South America, the annual 

and per-well oil discovery rates declined in the 1960's and 

1970's and then increased in the 1980's (see figs. 5 and 6) 

because of large deep-water discoveries (Campos Basin, 

Brazil) and discoveries in deep horizons of provinces in 

eastern Venezuela. The North Sea discoveries accounted for 

the increase in average annual oil and per-well discovery 

rates in Western Europe. However, average annual and 

per-well oil discovery rates have declined dramatically in 

Western Europe since they reached a maximum during 

1970-75. 

Petroleum exploration in the period from 1955 to 

1960 resulted in major discoveries in North Africa and 

Nigeria. Figures 5 and 6 show that, since that period, 

average annual and per-well discovery rates have declined 

dramatically in Africa. After 1975, most of the oil was 

discovered offshore. 

Offshore discoveries accounted for most of the oil 

discovered since 1965 in non-Communist Asia. The perwell Asian discovery rates increased in 1960-70 as exploration shifted offshore. Nearly all the oil discovered in the 

southwestern Pacific was offshore. 

The regional average annual gas discovery rates are 

presented in figure 7. The quality, reliability, and availability of gas data will not support the intensive analysis that 

crude-oil data have been subjected to. Historically, naturalgas discoveries and the associated gas in crude-oil fields 

have been underreported. Even in the United States, it is 

estimated that at least 24 trillion cubic feet of associated gas 

was flared between 1935 and 1971 (Rotty, 1974). The 

development of seamless pipe, which permitted transmission of natural gas long distances without significant product losses, allowed gas producers to expand gas markets 

beyond their immediate location. The gas price increases in 

the 1970's and 1980's provided incentives for U.S. gas 

Exploration and Discoveries Since 1950 3 
producers to search intensively for and develop moderatesize gas fields. Even with well-organized gas markets, half 

of the gas wells drilled in the United States have been 

drilled since 197 4. The halfway point for oil wells drilled 

was in 1954. Areas outside of the United States are 

generally not as far along in exploration and development of 

their gas resources. Outside the United States there is 

evidence that gas is becoming more than simply a byproduct 

of oil production. 

In most of the published international data, no distinction is made between associated or dissolved gas, which 

is associated with and frequently entrained in crude oil, and 

nonassociated gas. Nonassociated gas reservoirs are generally developed for natural gas as the primary product. Under 

this definition, about three-fourths of the U.S. gas is 

nonassociated. Because Petroconsultants provides field 

rather than reservoir estimates of ultimate oil and gas 

recovery, a field was classified as either a crude oil field 

having associated gas or a nonassociated gas field on the 

basis of the field's gas-to-liquids ratio. 

Nonassociated gas fields were defined as having 

gas-to-liquids ratios of at least 20,000 cubic feet to one 

barrel of liquids. By this definition, at least 80 percent of 

the gas reported by Petroconsultants in Western Europe, 

Asia, and the southwestern Pacific is in nonassociated gas 

fields (see table 3). For the whole study area, 64 percent of 

gas was classified as nonassociated. With the exception of 

Western Europe and Africa, most areas had at least twothirds of their nonassociated gas discovered since 1970. In 

the study area, 60 percent of the nonassociated gas, but only 

25 percent of the oil, was discovered since 1970. This 

indicates that active exploration for, and development of, 

gas are relatively recent phenomena. 

Without more detailed information on the geologic 

nature of oil and gas occurrence, it is not possible to 

accurately estimate the degree that identified gas resources 

may be understated. For the United States and Canada, the 

overall gas-to-oil ratio is between 5 and 6, that is, thousands 

of cubic feet per barrel of crude oil. For the study area, this 

ratio is 2.5; on the basis of regions, the ratios, from lowest 

to highest, are as follows: South America, 1.4; the Middle 

East, 1.8; Africa, 2.5; Asia, 6.7; Western Europe, 8.0; and 

the southwestern Pacific, 14.3. Regions with advanced 

domestic and export gas markets have the highest ratios. 

SIZE DISTRIBUTION OF PETROLEUM 

PROVINCES 

Study Area 

The rate of oil discovered per wildcat well is determined, in part, by the size distribution of undiscovered 

fields within a petroleum province. Original province fieldsize distributions are typically highly skewed, where a few 

large fields are so large that they contain most of the 

recoverable oil in a province. The distribution· is important 

because once these very large fields are discovered, 

improvements in geologic understanding or exploration 

technology will generally be insufficient to sustain the 

initial discovery rate. The discovery rate drops because the 

remaining fields are orders of magnitude smaller than the 

large discoveries. Improvements in technology and geologic understanding, however, will help to mitigate exploration risks. 

Within a province, rapidly declining discovery rates 

produce declining returns to exploration, and they, in tum, 

encourage explorationists to begin exploring new provinces. The size distribution of provinces is also skewed when 

size is measured in terms of barrels of recoverable oil. The 

ultimate recovery of oil in provinces is not nearly as well 

defined as that in fields because provinces are not as 

completely delineated and evaluated as individual fields. 

Petroleum exploration continues in both new and old 

provinces. Comparison of province size is necessarily 

confined to hydrocarbons discovered to date and omits the 

undiscovered portion of the province. 

As a result of differences in geologic interpretations 

and availability of data, there is now no universally 

accepted set of definitions and delineations of the world's 

petroleum provinces. Fields contained in the files of Petroconsultants are cross-referenced by specific province names 

provided by Petroconsultants. In order to enhance the 

chances that province names corresponded to accepted 

nomenclature, the province names were chosen from the set 

provided by Petroconsultants that represented the greatest 

level of aggregation in the geologic and geographic sense. 

Collectively, fields in the study area were designated 

with 351 unique province names. For the purposes of this 

report, a province is considered significant if it has at least 

one field containing at least 100 million barrels of recoverable crude oil discovered by 1991. According to this 

designation, there were 99 different significant provinces in 

the study area. Table 4 lists the 99 significant provinces by 

region, with estimates of the amount of oil and gas 

discovered through 1990 in each province. The significant 

provinces account for just over 99 percent of the 1, 144 

billions of barrels of recoverable oil found in the study area. 

Figure 8 shows the size distribution of the 99 significant provinces in the study area. The distribution is highly 

skewed. The largest province, the Arabian Basin, 

accounted for almost half of the discovered oil in the study 

area. The largest four provinces in terms of discovered oil 

accounted for more than 70 percent of the total oil discovered and about 85 percent of the gas discovered in the study 

area. On a regional basis, the distribution of known recoverable oil is as follows: the Middle East, 62 percent; South 

America, 12 percent; Africa, 10 percent; Mexico and 

Western Europe, 5 percent each; Asia, 4 percent; and the 

4 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
southwestern Pacific, 0.5 percent. Central America and the 

Caribbean do not contain any significant provinces. 

Figures 9 to 12 display, for four regions, the temporal 

ordering of the first discovery in each significant province 

as well as the relative size of each province in terms of oil 

discovered. The significant provinces in seven regions are 

discussed below. 

Mexico 

Discoveries in Mexico's largest provinces, the 

Tampico-Misantla Basin and the Salina Basin, occurred 

before 1905. The Tampico-Misantla Basin includes the 

Golden Lane area and the giant Chicontepec field, which is 

estimated to contain over 12 billion barrels of recoverable 

oil. The Salina Basin is in the Chiapas-Tobasco region and 

contains the Reforma area fields, including the Bermudez 

Complex. The large offshore discoveries in the Gulf of 

Campeche, which extend the Cantarell Complex, were 

made in the late 1970's. The most recent discoveries of at 

least 100 million barrels were in the Salina Basin and 

occurred in 1982. 

South America 

Maracaibo Basin, Eastern Venezuela Basin, and the 

Greater Furrial Trend 1 contain the largest quantities of 

discovered oil in South American onshore basins. Oil in 

each of these provinces was discovered before 1930. 

Together the three provinces account for about 70 percent of 

the oil discovered in South America. The largest South 

American field, Bolivar Coastal located in Venezuela and 

Colombia, is credited with 36.7 billion barrels of oil 

(BBO). About 18 percent of the oil and 28 percent of the 

gas discovered in South America are offshore. The seven 

significant South American provinces that had reported 

discoveries since 1985 are Maracaibo Basin, Greater Furrial 

Trend, Neuquen Basin, Llanos Basin, Austral Basin, Campos Basin, and Santos Basin. Venezuela accounts for 77 

percent of the oil discovered in South America. 

Western Europe 

Of the oil and gas discovered through 1990 in 

Western Europe, 90 percent of the oil and 60 percent of the 

gas were in offshore fields. The North Sea Graben, the 

largest province in Western Europe, accounts for more than 

three-fourths of the oil discovered in that region. Many of 

the onshore provinces, particularly in southern Europe, are 

considered to be gas prone rather than oil prone. Since 

1 Although many geologists consider the Greater Furrial Trend to be 

a play in the Eastern Venezuela Basin, Petroconsultants lists it as a separate 

province. 

1985, seven of the twenty-one provinces of Western Europe 

have had discoveries of at least 100 million barrels in size. 

These discoveries have been made in the North Sea Graben, 

the Vestland Arch, the East Shetland Platform, the 

Norwegian-Danish Basin, the Kristiansund-Bodo Fault 

Complex, the Voring Basin, and the Anglo-Paris Basin. 

Middle East 

The Arabian Basin and the Zagros Fold Belt together 

account for three-fifths of the oil in the study area. Both 

were identified before 1940. The Arabian Basin contains 25 

supergiant fields (defined as having at least 5 BBO). The 

world's two largest oil fields, Ghawar and Burgan, both 

containing more than 80 BBO of recoverable oil, are also in 

the Arabian Basin. There are five supergiant fields in the 

Zagros Fold Belt. Offshore fields contain about one-fifth of 

the oil and one-third of the gas in the Middle East. With the 

exception of the Qom Basin, all the significant provinces in 

the Middle East have reported new discoveries of at least 

100 million barrels since 1985. 

Africa 

Of the 13 significant petroleum provinces in Africa, 

the 4 largest contain more than 80 percent of the oil 

discovered to date. Most of the oil in Africa, as well as 

nearly all of the significant provinces, was identified after 

1950. Africa's three supergiant fields-Hassi Messaoud, 

with 11 BBO in the Hassi Messaoud High; Sarir, with 5 

BBO in the Sirte Basin; and Amal, with 6 BBO also in the 

Sirte Basin-are all in North Africa. Only the Niger Delta, 

the Gabon Coastal Basin, and the Lower Congo Basin have 

reported individual discoveries of at least 100 million 

barrels of oil or greater since 1985. About one-fourth of the 

oil and 16 percent of the gas in Africa are in offshore fields. 

Initial African discoveries were along coastal areas in North 

Africa. During the 1970's and 1980's, exploration was 

carried to some interior areas. The very low gas-to-oil ratios 

in most of the African provinces probably reflect understatement of the gas resources discovered because of low 

commercial value. 

Non-Communist Asia 

In non-Communist Asia, 13 of the 23 significant 

provinces were already identified with discoveries by the 

end of 1950. Thus far, no supergiant fields have been 

discovered in this area. However, 6 of the 23 provinces had 

discoveries of at least 1 BBO. These provinces are Kutei 

Basin, Baram Delta, Central Sumatra Basin, Malaya Basin, 

West Java Basin, and Bombay Basin; together they account 

for nearly three-fourths of the oil discovered. Offshore 

fields contain 43 percent of the oil and 60 percent of the gas. 

Size Distribution of Petroleum Provinces 5 
The five provinces having 100-million-barrel discoveries 

since 1985 are the South Sumatra Basin, Baram Delta, West 

Java Basin, Bombay Basin, and Cauvery Basin. 

Southwestern Pacific 

The significant provinces of the southwestern Pacific 

are in Australia and Papua New Guinea. The Gippsland 

Basin accounts for about three-fourths of the oil discovered. 

Offshore fields contain 86 percent of the oil and 71 percent 

of the gas. Discoveries of at least 100 million barrels of oil 

have been reported since 1985 in the North Carnarvon Basin 

and Papuan Fold Belt. 

DELINEATED PROSPECTIVE AREA 

Explored and Delineated Prospective Areas 

Oil and gas exploration has typically been confined to 

only a small fraction of the land area of any given country. 

Petroleum exploration is generally focused on sedimentary 

basins where oil and gas might have formed. Sedimentary 

basins are not uniformly distributed throughout the world. 

Moreover, only relatively small fractions of most sedimentary basins have been intensively drilled. The geologic 

information used to site exploration and development wells 

obviously cannot be replicated by any single source, but the 

well locations, density of drilling, and results of exploration 

reflect the industry's collective evaluation of the area. 

Drilling density is often used to gauge the exploration 

maturity of an area. However, drilling density is more often 

calculated relative to the area within a given political 

boundary rather than relative to the area of interest to 

explorationists. The concepts of prospective and explored 

areas are introduced to allow the delineation of areas that 

have been subjected to a minimum threshold level of 

exploration. The explored area is a part of the prospective 

area where the density of wells probably precludes very 

large or giant discoveries. 

As used here, the prospective area delineated by 

drilling, that is, the delineated prospective area, is defined 

as that area reasonably close to wells and interior to the area 

drilled. The area is computed as the combined area of 

triangles having a well at each vertex. Only the triangles 

small enough to be covered by a circle of 20-mile radius are 

used. The 20-mile radius was chosen to correspond to the 

scale convenient for presentation in this report and to the 

precision of drilling and discovery data available. A much 

smaller radius than 20 miles would have produced numerous holes in the prospective areas evaluated, whereas a 

much larger radius would have resulted in a loss of 

resolution in defining the prospective area. The delineated 

prospective area within 2 miles of a well is called the 

explored area. Except at depths not already tested, it is 

unlikely that very large fields remain to be discovered in 

explored areas because such fields typically have planar 

surface areas much larger than 2 square miles. The recently 

discovered deep giant field El Furrial (in Venezuela) is just 

such an exception. In the study area, the total explored areas 

account for only 19 percent of the delineated prospective 

area. Much of the delineated prospective area may never 

become as densely drilled as explored areas because it was 

found to be unproductive and not worth further evaluation. 

The algorithm for computing and locating the delineated prospective area began with the identification of 

possible locations with grid points at a 2.8-mile spacing. 

Each grid point was identified by longitude and latitude. 

Field locations and all available well locations (for exploration, development, and production wells) were used in the 

computations. If the wells were redundant, that is, close to 

each other, they did not generally add to the prospective 

area. The well and field locations were compared to nearby 

wells and grid points to determine whether any grid point 

close to a well (or field) met the criteria for inclusion in the 

prospective area. Each grid point in the prospective area 

was also designated with the year that the point became part 

of the prospective area and whether the grid point was 

closest to a field or well. Grid points closest to the fields 

were assigned the oil and gas associated with the field. 

Although the nearest grid points of an isolated well are 

shown on the maps in figures 17-54, such grid points add 

only 1 square mile to the total delineated prospective area. 

The method of calculating prospective and explored 

areas has been refined somewhat from the procedures used 

in U.S. Geological Survey Circular 981. The earlier method 

treated grid points along the north-south and east-west axes 

differently than grid points in other directions. In the 

method used here, all directions are treated the same. Also, 

all isolated wells are now assigned an area of 1 square mile, 

rather than the 8 square miles assigned by the earlier 

method. Therefore, prospective and explored areas in some 

countries are smaller in this circular than in Circular 981 

even where the number of wildcat wells has increased. 

Delineated Prospective Area by RegionExploration and Discovery 

Computations of delineated prospective areas and 

explored areas for individual countries are presented in 

figures 17-54. Figures 13 and 14 and table 5 summarize the 

results when the individual country computations are aggregated to the regional level. Figures 13A and 14 show the 

profiles of the growth in prospective and explored areas 

when expressed on the bases of wildcat wells. The shape of 

the curve indicates whether wildcat wells were opening new 

areas or whether they followed earlier drilling and were 

sited in areas already classified as prospective. A linear 

curve indicates that there was a constant increment in 

prospective area with each wildcat well drilled. A rollover 

6 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
in the graph signifies that a larger proportion of the wildcat 

wells were sited in areas already considered prospective. 

Alternatively, an increase in the slope implies that wildcat 

wells were opening new areas. 

Figures 13B and 15 show the profiles of cumulative 

oil discovered through 1990 when the discovery date is 

replaced by the date when the nearest grid point to the 

discovery became part of the delineated prospective area. A 

rolling over of the curve suggests that the newly added 

prospective area is not as rich in terms of discovered oil as 

the older areas. If the industry were operating so that the 

most productive areas were explored early, a rollover in the 

graph would occur. A graph with a constant slope implies 

that the newly added area is just as productive as the old 

area, whereas a graph with an increase in slope signifies that 

the latest prospective area is richer than the early prospective area. These figures reflect the quality of the prospective 

area as well as the efficiency of the industry's exploration 

program. 

Figures 13A and 13B show the aggregate profiles for 

the study area. The delineated prospective area accounts for 

about 7 percent of the land area, and the explored area 

amounts to 19 percent of the delineated prospective area. 

About half of the total prospective area was delineated by 

1970. This area contained about 80 percent of the oil 

discovered to date. Since 1970, the growth of prospective 

and explored areas has been relatively constant while the 

amount of oil discovered per square mile of prospective area 

has dropped dramatically. 

The delineated prospective area in South America has 

more than doubled since 1970. The area added since 1971 

contains about 16 percent of the cumulative oil (see figs. 14 

and 15). Most of the oil in the recently added prospective 

area is in the Campos Basin, a deep-water Brazilian 

offshore province. In South America, total prospective area 

amounts to about 6.2 percent of the land area, and the 

explored areas amount to about one-fourth of the prospective area. Although South America and Western Europe 

have about the same number of wildcat wells. and prospective area, Western Europe has half the oil. The prospective 

area profile for Western Europe (fig. 14) shows a steep 

increase in prospective area per wildcat well in the late 

1960's, reflecting the exploration of the North Sea provinces. The prospective area delineated after 1971 accounts for 

less than half the total prospective area but has nearly 70 

percent of the oil discovered. North Sea exploration added 

new prospective area, and this new area contains most of 

Western Europe's discovered oil. 

The Middle East accounts for 62 percent of the oil 

discovered in the study area. Supergiant fields that were 

discovered early dominated the discovery history of the 

area. Nearly 90 percent of the oil discovered was located in 

the area that became prospective by 1971 (see fig. 15). 

Africa has about the same prospective area as Western Europe but is not nearly as well explored. Africa's 

prospective area represents less than 4 percent of the land 

area. Most of the interior regions of Africa have not had 

sufficient exploration to be classified as part of the prospective area. Even though the growth in prospective area in 

Africa has been at a relatively constant rate in terms of area 

added per wildcat well, the prospective area delineated by 

1971 contains almost 90 percent of the region's oil (see figs. 

14 and 15). 

In non-Communist Asia, only 21.4 percent of its 

prospective area was delineated before 1971 (fig. 14). This 

early area contains 62 percent of the oil discovered (fig. 

15). Since 1970, Indonesia has had its prospective area 

quadruple, and all other countries in the region have had 

their prospective areas at least double in size. 

In the southwestern Pacific, 80 percent of the oil was 

discovered in the prospective area delineated by 1971. Even 

though the southwestern Pacific is comparable to nonCommunist Asia in land area, its prospective area had 

cumulative discoveries that are much smaller. Natural gas is 

regarded as an economic commodity in both regions, and so 

part of the wildcat drilling was directed at gas. 

Other Applications of Delineated Prospective 

Area 

The concept of delineated prospective area can be 

applied (1) to partition areas for discovery-process modeling and (2) to characterize the relative richness of older or 

newly added prospective areas. In the first application, the 

concept of the delineated prospective area is used as a tool 

for identifying wildcat wells and discoveries within 

bounded areas so that discovery decline functions can be 

used to project future discoveries. In particular, the partitioning of areas is used to separate the confounding effects 

of crowding of wildcat wells in areas that have already had 

some exploration from the erratic arrival of discoveries in 

newly opened areas. Typically, the prospective area is 

partitioned into an early and late part, and then wildcat 

wells and discoveries are assigned to each part on the basis 

of location. The empirical discovery rate for the early part 

generally shows sufficient regularity that it can be estimated. The discovery-rate function for the late part is 

estimated by using the rate of decline for the early part, but 

adjustments compensate for the relative richness of the two 

different areas; specifically, the decline rate for the early 

area and the discovery sizes for the late area are used to 

estimate the ultimate number of fields in the late area (see 

Attanasi and Root, 1988, for details). 

A second application of prospective area is to determine the relative richness of new areas that have recently 

been the target of petroleum exploration. The graph showing the expansion of the delineated prospective area in the 

whole study area (fig. 13A) indicates that about 40,000 to 

50,000 square miles of new prospective area is added per 

year or about 50 square miles per wildcat well. Figure 13B 

Delineated Prospective Area 7 
shows the quantities of crude oil found to date in the 

prospective area in the study area when the areas are 

ordered according to the date when their location was 

classified as prospective. About a third of the prospective 

area accounts for 80 percent of the discoveries. There 

continue to be major discoveries, but the flattening of the 

curve indicates that the area delineated early is richer than 

the areas delineated later. This shape suggests that, in the 

aggregate for the study area, explorationists have been 

relatively efficient in delineating the richest area early. For 

regions where changes in economics or the state of technology were required to make an area commercially attractive, such as the North Sea of Western Europe or the deep 

waters off of Brazil, South America, the slope of the graph 

of oil ordered by prospective area sharply increases (see fig. 

15). This shape indicates that relatively large quantities of 

oil were discovered in the more recently added prospective 

areas. 

GROWTH IN ESTIMATES OF FIELD SIZES 

In the United States and Canada, it has long been 

recognized that the initial estimates of field size (ultimate 

recoverable oil) are conservative and tend to increase as the 

fields are developed and placed into production. During the 

period from 1977 through 1988, oil and gas estimates of 

ultimate recovery in pre-1978 discoveries in the lower 48 

United States increased by 21 billion barrels (from 145 to 

166 billion barrels) and by 148 trillion cubic feet (from 735 

to 883 trillion cubic feet), respectively (Energy Information 

Administration, 1990). Reserve appreciation in old fields 

typically accounts for two-thirds to three-fourths of annual 

additions to U.S. proved reserves. 

Several explanations are given for the field-growth 

phenomenon. Initial engineering estimates are conservative 

because the economic penalties for overestimation are more 

severe than those for underestimation. Initial engineering 

estimates need only be detailed enough to estimate a 

minimum threshold field size that will allow an operator to 

proceed with field development and therefore are not 

intended to measure the full potential of the new discovery. 

Field growth is also an economic phenomenon. During periods of high prices, development drilling is generally 

accelerated and at higher intensity (that is, closer well 

spacing). For example, in the United States, natural gas in 

pre-1967 discoveries grew 35 trillion cubic feet from 1967 

to 1977 (American Petroleum Institute, American Gas 

Association, and Canadian Petroleum Association, 

1967-78). These same fields also grew 87 trillion cubic feet 

from 1977 to 1987 (Energy Information Administration, 

1990). Price increases allowed the commercial use of 

enhanced oil-recovery techniques in California's heavy-oil 

fields, resulting in a 20 percent increase in estimates of 

California's ultimate oil recovery in the period from 1977 

to 1988. 

There is evidence that field growth also occurs 

outside of the United States and Canada, but available data 

are probably not yet reliable enough to develop traditional 

growth factors that would permit projection of additions to 

reserves from growth in identified fields. Petroconsultants 

provides field estimates of ultimate recovery of oil and gas 

in field file tapes issued four times a year to subscribers. 

Figure 16A shows cumulative discoveries in the five main 

regions of the study area from 1900 to 1980 computed from 

the data on the first tape issued in each of years 1981 , 1984, 

1987, and 1990. Figure 16B shows cumulative discoveries 

for the same regions as in figure 16A except that data for the 

Middle East are omitted. The figures show increases in the 

estimates of cumulative oil from more recent tapes. Some of 

the apparent growth is, however, due to missing discovery 

data. 

Missing data account for about half the difference 

between the 1981 and 1984 curves in figure 16A and for 

about two-fifths of the difference between these curves in 

figure 16B. The missing data are fields discovered before 

1980 but added to the Petroconsultants' data by 1984. Less 

than 10 percent of the difference between the 1984 and 1990 

curves in figure 16A,B was the result of missing data. Table 

6 shows how the estimates of cumulative oil discovered 

from 1900 to 1980 in the study area regions changed from 

the 1984 to 1990 tapes. 

Even though data presented in figure 16 and table 6 

provide evidence of field growth outside of the United 

States and Canada, little is known about how the estimates 

of ultimate field recovery were made and if the method has 

been applied consistently. The field-growth phenomenon 

explains why proved reserves in the study area continued to 

increase even though estimates of aggregate annual discoveries are much smaller than annual production. It implies 

not only that recent discoveries are substantially understated, but that field growth could become the dominant 

source of additions to proved reserves in future years. 

SUMMARY AND CONCLUSIONS 

Data on wildcat wells showed exploration drilling 

continuing at a relatively constant rate in spite of significant 

changes in world oil prices. Price increases appear to have 

allowed commercial exploration and development of fields 

in high-cost areas, such as the North Sea and Campos 

Basin. The proportion of wildcat wells drilled offshore in 

the study area has increased dramatically over the last 30 

years, and recent data show that about 4 of 10 new wildcat 

wells drilled in the study area are offshore wells. If the 

pattern of wildcat drilling is analyzed in relation to the 

growth in prospective area, one can conclude that drilling in 

the study area has continued to open up new areas at nearly 

a constant increment per wildcat well. 

Although the annual oil discovery rate in the 1980's is 

lower than that in the 1970's, it is too early to tell the extent 

8 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
of the decline. Discovery data for the latter part of the 

decade are incomplete, and it is likely that the estimated 

sizes of the discoveries in the early 1980's will be revised 

substantially upward as development and production occur. 

Comparison of the gas-to-oil ratios in areas having markets 

for gas with those having no markets suggests that gas 

contained in new discoveries for the study area has historically been understated. Since 1970, most of the natural gas 

discovered is in nonassociated gas fields, suggesting, perhaps, that gas is starting to be regarded as a commercial 

commodity. 

The size distribution of petroleum provinces is highly 

skewed. In particular, of the 99 significant provinces 

identified in the study area, the largest 4 account for 70 

percent of the oil. Discovery statistics indicate that most of 

the large provinces continue to have discoveries of at least 

100 million barrels. The skewed distribution in province 

sizes and stability in province size orderings suggest that 

intense exploration in identified provinces will not change 

the distribution of oil within the study area. 

The notion of prospective area was devised to identify 

areas that have been subjected to a minimum threshold of 

exploration. The matching of discoveries with prospective 

area and the dates when the field location became part of the 

prospectiv~ area allows construction of profiles of the 

discovered oil ordered by prospective area. For most 

regions, profiles showed that the industry had identified the 

most productive areas early in the exploration process. The 

North Sea discoveries of Western Europe and the Campos 

Basin discoveries in South America are exceptions, representing late prolific prospective areas. 

The reader can examine the location of the prospective and explored areas for individual countries and small 

groups of countries in figures 17-54. Maps are labeled with 

the names of petroleum provinces and the year of the 

earliest discovery we know of in each province. Profiles 

showing the growth in prospective and explored areas as 

well as the oil discovered by prospective area are also 

presented. The salient statistics about exploration and petroleum provinces in each country or group of countries are 

presented in figures 17-54. 

Evidence of the field-growth phenomenon outside the 

United States and Canada was demonstrated. However, 

without estimates of ultimate field recovery consistently 

constructed over a number of years, the data are not reliable 

enough to project the magnitude of the expected field 

growth into the future. Because a significant component of 

field growth is driven by economic forces, the magnitude of 

the potential additions to proved reserves from this source 

may not become apparent until (if ever) the fields in the 

study area are as intensively developed as those in the 

United States and Canada. 

REFERENCES CITED 

American Association of Petroleum Geologists (AAPG), 

1951-86, Foreign developments issues of the AAPG Bulletin: v. 35-70. 

American Petroleum Institute, 1992, Basic petroleum data 

book-Petroleum industry statistics: v. 12, no. 1, pages 

unnumbered. 

American Petroleum Institute, American Gas Association, and 

Canadian Petroleum Association, 1967-78, Reserves of 

crude oil, natural gas liquids, and natural gas in the United 

States and Canada [annual volumes for the years 1966-77]: 

Washington, D.C., American Petroleum Institute, v. 21-32. 

Attanasi, E. D., and Root, D.H., 1988, Forecasting petroleum 

discoveries in sparsely drilled areas-Nigeria and the North 

Sea: Mathematical Geology, v. 20, no. 7, p. 763-776. 

Energy Information Administration, 1990, U.S. oil and gas 

reserves by year of field discovery: U.S. Department of 

Energy Report DOE/EIA--0534, 137 p. 

G. & C. Merriam Company, 1975, Webster's new collegiate 

dictionary: Springfield, Mass., 1536 p. 

Penn Well Publishing Company, 1986-90, International Petroleum Encyclopedia: Tulsa, Okla., v. 19-23. 

Random House, Inc., 1973, The Random House college dictionary: New York, 1568 p. 

Root, D.H., Attanasi, E.D., and Turner, R.M., 1987, Statistics of 

petroleum exploration in the non-Communist world outside 

the United States and Canada: U.S. Geological Survey 

Circular 981, 133 p. 

Rotty, R.M., 1974, First estimates of global flaring of natural gas: 

Atmospheric Environment, v. 8, p. 681-686. 

U.S. Central Intelligence Agency, 1991 , World fact book 1991: 

Washington, D.C., 405 p. 

References Cited 9 

TABLES 1-6 

[Figures 1-54 follow table 6] 
~ 

~ Table 1. Exploration wells by year, 1950-89, for the Caribbean, latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the 

southwestern Pacific 

., [Data for 1950--80 are from the annual foreign developments issues of the Bulletin of the American Association of Petroleum Geologists (AAPG). Data for 1980--85 are from these annual issues and from tD compilations of the AAPG data published in the International Petroleum Encyclopedia. Data for 1985-89 are from the International Petroleum Encyclopedia] ... 

a 

ii' 

c Area 1950 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 3 

m 

>< 

~ Mexico ....................... 100 129 111 128 121 114 113 108 76 133 176 160 133 99 109 139 153 135 151 134 s-

.. 

~ Caribbean s· 

~ 

Bahamas ...................... 0 Q 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 .. Cuba1 .••••••••••••••••••••••• 0 0 0 1 0 31 45 27 28 10 0 11 4 0 7 0 0 0 0 0 s: 

Q"' Haiti ......................... 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 tD Dominican Republic ........... 0 0 0 0 0 0 0 0 3 0 2 0 0 0 0 0 AI 0 0 1 7 ... = 

r- Jamaica ....................... 0 0 0 0 0 1 0 3 0 0 0 0 0 0 0 0 0 0 0 0 ~ Barbados ..................... 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0 0 9 1 0 0 :r Lesser Antilles2 ••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 > 3 - - - - - - - - - - - - - - - - - - - -

~ Subtotal .................. 0 0 0 1 1 34 45 31 32 11 2 11 4 0 7 0 9 1 1 7 

~- Central America3 

~ 

c 

m Belize ........................ 0 0 0 0 0 1 1 1 6 0 0 1 4 1 0 0 0 2 0 0 .. 

Q Honduras ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 J Guatemala .................... 0 0 0 0 0 0 0 0 5 0 3 2 1 0 0 0 0 0 2 0 ... 

=- Nicaragua ..................... 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 2 5 tD 

~ Costa Rica .................... 0 0 0 0 0 3 2 0 1 2 2 0 1 2 0 0 0 0 0 0 

a: Panama ....................... 0 0 0 0 0 0 1 1 2 0 0 1 3 0 0 0 0 0 0 0 Q. - - - - - - - - - - - - - - - - - - - - ii' 

m Subtotal. ................. 0 0 0 0 0 4 4 3 14 2 5 4 9 4 0 0 0 3 4 6 AI 

~ South America 

> :::-

;:;· Colombia ..................... 4 8 50 14 24 20 18 26 32 60 50 39 20 22 30 20 24 18 21 30 .fJ Venezuela .................... 66 99 111 151 178 165 140 174 193 110 72 80 64 51 53 56 26 31 29 33 z 

Q Trinidad and Tobago .......... 9 9 7 5 9 10 22 19 12 17 24 31 20 37 53 37 36 14 23 20 

n = Guyana ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 6 0 0 Q 

3 Suriname ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 2 1 4 17 

3 French Guiana4 •••••••••••.... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 c 

= Ecuador ...................... 2 4 25 24 23 26 16 25 3 6 8 4 0 0 6 21 31 14 8 8 ii 

;: Peru .......................... 32 43 38 62 55 24 31 16 14 3 21 26 25 26 8 30 24 50 36 38 

~· Bolivia ....................... 2 1 0 0 6 2 5 0 9 12 18 14 13 10 13 16 15 28 28 15 

AI Uruguay ...................... 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

Q. = Paraguay ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 ... 

=- Brazil ........................ 6 4 4 6 6 10 8 38 56 92 95 76 70 89 86 98 98 110 115 86 tD 

(I) Chile ......................... 5 4 6 12 20 13 15 17 20 19 11 14 19 14 14 8 15 10 17 19 

~ Argentina ..................... 0 23 47 40 54 48 51 38 33 0 121 84 130 76 55 78 116 92 85 86 

;: - - - - - - - - - - - - - - - - - - - - I") Subtotal .................. 126 195 288 314 376 318 306 353 372 319 420 368 361 325 319 364 390 377 366 352 

5 

I") 
Area 1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 TOTAL 

Mexico ....................... 130 129 143 104 98 87 79 79 83 83 85 63 65 65 44 78 68 27 33 24 4089 

Caribbean-Continued 

Bahamas ...................... 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 4 

Cuba1 •••••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 165 

Haiti ......................... 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 5 

Dominican Republic ........... 2 0 0 0 0 0 0 0 0 3 0 0 1 0 0 0 0 0 0 0 19 

Jamaica ....................... 1 1 1 0 0 0 0 0 0 0 0 2 4 0 0 0 0 0 0 0 13 

Barbados ..................... 1 2 0 0 0 0 0 0 1 0 0 3 0 0 10 5 2 0 0 2 39 

Lesser Antilles2 ••••••••••••••• 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 2 - - - - - - - - - - - - - - - - - - - - -

Subtotal .................. 5 4 1 0 0 0 0 4 1 3 0 5 6 0 10 5 4 0 0 2 247 

Central America3 -Continued 

Belize ........................ 0 0 5 3 0 4 0 0 0 2 0 3 2 0 1 3 0 0 0 0 40 

Honduras ..................... 0 1 3 3 0 1 0 0 2 0 2 0 0 0 0 0 0 0 0 0 14 

Guatemala .................... 0 0 1 1 2 3 5 0 0 3 4 6 9 0 0 4 4 0 2 4 61 

Nicaragua ..................... 8 3 0 0 3 2 0 3 3 0 0 0 0 0 0 0 0 0 0 0 31 

Costa Rica .................... 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 3 2 1 20 

Panama ....................... 0 1 0 0 2 0 0 0 1 1 0 0 0 0 0 0 0 0 0 3 16 - - - - - - - - - - - - - - - - - - - - -

Subtotal ................. 8 5 9 7 7 11 5 3 6 6 6 9 11 0 1 7 4 3 4 8 182 

South America-Continued 

Colombia ..................... 16 17 20 20 24 14 21 27 29 30 34 114 73 35 42 67 44 49 85 72 1363 

Venezuela .................... 38 44 64 63 76 35 45 48 46 63 142 351 250 19 18 6 25 177 17 23 3432 

Trinidad and Tobago .......... 21 35 23 15 13 14 12 17 8 13 13 16 23 11 4 14 8 8 6 8 696 

Guyana ....................... 0 1 0 0 2 3 1 0 0 0 0 1 2 0 0 0 0 0 0 0 19 

Suriname ..................... 7 1 0 0 0 1 0 0 1 0 0 0 3 0 3 8 9 9 11 8 86 

French Guiana 4 ••••••••••••••• 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 2 

Ecuador ...................... 20 15 20 8 5 3 3 5 3 9 0 3 5 10 3 2 4 9 14 11 406 

Peru .......................... 28 21 25 31 43 43 36 37 28 3 13 17 12 23 29 13 11 13 8 7 1043 

Bolivia ....................... 10 4 8 4 7 7 16 14 13 12 6 19 18 9 3 11 4 10 12 13 407 

Uruguay ...................... 0 0 0 0 0 0 2 0 1 0 0 0 0 0 0 0 3 1 0 0 8 

Paraguay ..................... 0 11 6 0 0 1 1 3 3 1 0 1 1 0 0 0 1 2 1 1 36 

Brazil ........................ 100 87 80 78 86 87 105 100 89 134 166 245 328 262 243 229 163 176 160 115 4186 

Chile ......................... 24 20 33 20 25 23 22 7 14 22 16 62 41 5 7 13 18 35 26 17 722 

Argentina ..................... 113 145 110 139 117 78 83 143 81 71 110 127 107 130 136 161 92 45 102 120 3467 - - - - - - - - - - - - - - - - - - - - --

Subtotal .................. 377 401 389 378 398 310 347 401 317 358 500 956 863 504 488 524 382 534 442 395 15873 

-1 1

Data for Cuba for 1960-89 are incomplete. Sll 

=- 2

For this report, the Lesser Antilles are considered to consist of the islands from Grenada to St. Thomas, except Barbados, which is listed separately. ;-

Ill 3

No exploration wells were reported for El Salvador. .... 4

French Guiana is listed separately although it is an overseas department of France. ~ 

.... 

~ 
...to Table 1. Exploration wells by year, 1950-89, for the Caribbean, latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the "'" southwestern Pacific-Continued 

"a 

~ Area 1950 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 a 

;r 

Western Europe5 c 

3 

m Norway ....................... 0 0 0 0 0 0 0 ~ 0 0 0 0 0 0 0 0 0 1 5 11 14 "'CC 

S" Svalbard6 .. ••••••••....•.......• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

a Sweden ....................... 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 3 1 1 s· 

,= Denmark ..................... 2 2 1 3 0 0 2 0 9 2 0 0 0 0 0 0 3 1 7 2 

n Ireland ....................... 0 0 0 0 0 0 0 0 0 0 0 0 2 4 0 0 0 0 0 0 I» 

.. United Kingdom .............. 2 1 1 4 7 15 10 6 17 9 8 4 0 6 5 21 33 39 39 55 s: 

cr Netherlands ................... 11 11 7 17 14 9 7 8 8 11 4 4 4 4 23 40 10 4 19 35 tD 

I» 

~ Belgium ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ..... West Germany ................ 63 125 140 80 103 107 113 107 123 99 76 53 49 46 16 36 57 40 42 45 a 

:r France ........................ 31 17 34 42 42 17 42 98 138 132 111 104 102 105 78 58 30 23 15 23 

> Switzerland ................... 0 0 0 1 0 0 0 0 1 0 3 2 1 2 3 2 1 0 0 0 

3 

tD Austria ....................... 0 0 0 0 0 0 15 21 13 17 17 11 11 11 13 17 16 8 14 19 .. Italy .......................... 6 3 35 26 27 41 56 72 72 80 78 68 83 69 70 37 46 24 31 38 ;:;· 

~ Greece ....................... 0 0 0 0 2 0 1 8 1 0 0 6 6 9 0 2 1 10 0 0 ~ Portugal ...................... 1 0 0 0 14 6 1 2 5 8 1 1 1 4 0 0 0 0 0 0 m 

c Spain ......................... 2 3 3 2 4 12 15 17 15 13 9 14 19 23 11 15 17 14 17 9 a Malta ......................... 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 "'CC 

!0 - - - - - - - - - - - - - - - - - - - -

;. Subtotal .................. 118 162 221 175 214 207 262 339 402 372 307 267 278 283 219 228 216 171 196 241 tD 

~ Middle East a: 

Q. 

;r Turkey ....................... 1 4 4 2 1 0 0 7 11 21 21 39 19 16 14 23 31 21 21 11 m Cyprus ....................... 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ~ Syria ......................... 1 0 0 0 0 0 1 0 1 4 2 0 0 0 0 0 1 0 1 1 

~ I..ebanon ...................... 0 0 0 1 0 0 0 0 0 0 1 0 0 2 6 0 1 1 0 0 ~· Israel ......................... 0 0 0 1 1 8 10 7 7 4 6 4 7 6 12 10 11 10 12 5 

z Jordan ........................ 0 0 0 0 0 0 0 1 1 3 1 0 0 0 1 5 0 0 0 1 Q 

= Iraq .......................... 1 2 0 6 5 4 8 6 7 5 10 5 0 0 0 0 0 0 0 2 

n 

Q Iran .......................... 2 0 1 0 0 0 2 4 2 3 3 6 9 8 16 7 19 40 9 11 

3 Saudi Arabia .................. 0 7 6 1 2 6 3 1 0 0 10 10 8 2 3 7 3 8 6 3 3 

c Kuwait ....................... 0 2 2 0 2 1 2 1 2 3 2 8 3 6 5 6 5 1 1 0 

= Former Neutral Zone 7 ••••••••• 3 1 1 0 3 2 1 0 0 0 1 4 7 9 0 2 3 2 0 0 !i 

t Bahrain ....................... 4 11 0 0 9 4 2 0 0 1 0 1 1 3 0 1 1 0 0 0 

~ Qatar ......................... 0 0 1 2 0 1 1 0 0 0 3 1 1 4 6 0 0 5 0 0 I» Oman ........................ 0 0 0 0 0 0 1 1 0 1 2 0 3 2 0 1 0 0 0 5 Q. = Yemen ....................... 0 0 0 0 0 0 0 0 0 ... 0 0 2 4 0 1 1 0 0 0 0 

tD 

::r United Arab Emirates .......... 0 1 1 0 1 1 2 2 3 4 4 0 4 5 8 5 16 11 13 12 

~ - - - - - - - - - - - - - - - - - - - - Subtotal .................. 12 28 16 14 24 27 33 30 34 49 66 80 66 63 72 68 91 99 63 52 

': 

t'l 

Si 

t'l 
Area 1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 TOTAL 

Western Europe5 -Continued 

Norway ....................... 13 13 14 13 18 14 21 14 14 26 35 41 50 50 18 43 41 33 - 23 525 

Svalbard6 ••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - 1 1 

Sweden ....................... 0 5 22 21 25 31 5 7 32 11 21 18 19 15 20 16 0 6 - 17 298 

Denmark ..................... 3 3 1 4 3 5 7 5 3 2 4 5 5 13 4 15 8 7 - 4 135 

Ireland ....................... 0 3 3 3 4 7 6 6 15 8 3 11 4 6 7 6 7 4 - 5 114 

United Kingdom .............. 34 32 34 55 74 93 70 72 45 60 81 92 123 141 64 187 210 142 - 184 2075 

Netherlands ................... 27 29 33 18 19 24 26 28 28 31 37 38 58 49 27 52 41 35 - 45 895 

Belgium ...................... 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 - 0 4 

West Germany ................ 24 27 26 22 30 26 29 37 27 49 37 65 62 44 48 44 34 24 - 12 2187 

France ........................ 14 7 11 11 9 11 15 14 17 24 24 38 50 28 40 49 78 38 - 47 1767 

Switzerland ................... 0 0 0 1 0 0 0 1 1 0 1 3 4 0 0 0 0 1 - 1 29 

Austria ....................... 15 25 21 21 24 37 36 26 33 28 26 33 37 21 23 23 13 24 20 12 701 

Italy .......................... 27 40 43 24 20 24 25 20 61 43 60 91 103 66 77 73 117 96 88 38 2098 

Greece ....................... 2 1 2 3 4 0 1 5 3 5 5 5 14 5 6 5 2 3 - 4 121 

Portugal ...................... 0 0 0 0 3 8 8 1 0 2 0 1 2 3 0 1 0 0 0 0 73 

Spain ......................... 7 13 7 19 10 16 23 18 18 18 24 33 19 24 15 21 18 12 - 10 559 

Malta ......................... 0 1 2 1 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 7 - - - - - - - - - - - - - - - - - - - - -- Subtotal .................. 166 199 219 216 243 296 272 254 297 307 359 478 551 465 349 535 569 425 108 403 11589 

Middle East-Continued 

Turkey ....................... 34 21 25 35 37 56 53 33 26 12 29 19 50 35 19 24 25 31 37 39 907 

Cyprus ....................... 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 

Syria ......................... 1 1 1 0 1 0 0 0 0 3 2 4 4 20 30 11 24 10 14 20 158 

ubanon ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 12 

Israel ......................... 8 6 4 2 1 9 12 12 5 7 11 8 14 18 0 2 3 2 1 3 249 

Jordan ........................ 0 3 0 0 0 0 0 0 1 0 0 0 0 5 0 0 0 0 0 0 22 

Iraq .......................... 1 0 1 3 2 1 2 5 0 0 0 0 0 0 0 0 2 10 19 2 109 

Iran .......................... 8 10 6 36 26 26 26 25 17 2 5 1 0 0 0 0 7 0 0 0 337 

Saudi Arabia .................. 2 4 10 7 9 21 16 12 8 37 40 49 25 4 0 7 6 0 3 3 349 

Kuwait ....................... 1 2 2 0 0 0 2 1 0 7 0 24 8 29 11 2 0 2 0 2 145 

Fonner Neutral Zone 7 ••••••••• 0 0 0 1 0 0 0 0 0 0 0 0 2 0 0 0 2 0 0 0 44 

Bahrain ....................... 0 0 1 1 0 1 0 0 1 0 1 14 0 0 0 0 0 0 0 0 57 

Qatar ......................... 3 4 5 1 0 0 2 0 2 2 4 2 4 2 3 3 0 0 7 3 72 

Oman ........................ 2 10 16 7 0 0 0 9 19 19 17 29 31 37 29 39 32 36 40 44 432 

Yemen ....................... 0 0 0 0 0 0 1 1 1 2 1 4 4 0 1 5 3 0 28 33 92 

United Arab Emirates .......... 14 9 15 16 12 9 20 9 0 0 14 13 26 34 17 27 13 0 8 4 353 - - - - - - - - - - - - - - - - - - - - --

Subtotal. ................. 75 70 86 109 88 123 134 107 80 91 124 167 168 184 110 120 117 91 157 153 3341 

-1 5

No exploration wells were reported for Andorra, Finland, Iceland, Liechtenstein, Luxemburg, or Monaco. Dashes in 1988 column indicate data not available. 1:11 

a- 6

Svalbard (or Spitsbergen) is a group of islands in the Arctic Ocean north of and belonging to Norway. tD 

II) 7

The former Neutral Zone was located between Kuwait and Saudi Arabia. ... 

~ 

... 

U1 
Table 1. Exploration wells by year, 1950--89, for the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the 

southwestern Pacific-Continued .... 

crArea 1950 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 

-a 

~ Africa8 

a 

;-

c Morocco ...................... 20 66 38 53 :40 26 12 5 5 3 4 13 8 3 8 5 12 9 8 14 3 

m Algeria ....................... 14 12 11 11 18 22 46 30 39 37 48 64 62 25 46 24 17 17 17 31 >< 

"C Tunisia ....................... 3 0 3 7 12 5 4 4 5 5 0 1 8 4 4 7 7 10 5 4 

S" Libya ......................... 0 0 0 0 0 0 0 4 25 41 98 125 173 245 167 136 62 41 80 70 !1 

c:r Egypt ........................ 6 0 0 0 3 4 2 5 5 2 6 4 6 12 9 8 14 7 21 23 

... = Western Sahara ............... 0 0 0 0 0 0 0 0 0 0 2 13 30 7 4 3 4 5 0 1 

n Mauritania .................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 AI 

"'I 

s: Mali .......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Cl"' 

tD Niger ......................... 0 0 0 0 0 0 0 0 0 0 0 0 6 1 2 0 0 0 0 0 AI 

... = Chad ......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 r- Sudan ........................ 0 0 0 0 0 0 0 0 0 0 0 1 3 2 0 0 0 0 0 0 ~ 

:r Senegal ....................... 0 0 0 0 0 0 0 0 3 11 5 8 1 0 0 0 2 5 2 3 

> The Gambia .................. 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 3 

~ Guinea-Bissau ................. 0 0 0 0 0 0 0 0 0 0 1 3 0 0 0 0 0 0 2 3 

;:;- Guinea ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 !-1 

~ Sierra Leone .................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

m Liberia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 c Ivory Coast ................... 0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 a 

"C Ghana ........................ 0 0 0 0 0 0 1 3 0 0 0 0 0 0 0 0 1 1 0 0 

!D Togo ......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 -:::r 

tD Benin ........................ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 2 

~ Nigeria ....................... 0 0 1 2 10 7 4 1 17 37 25 15 5 22 37 65 66 79 38 27 a: 

Cl.. Cameroon .................... 0 0 14 3 2 2 3 3 1 1 0 0 0 0 0 1 0 4 1 1 

;- Equatorial Guinea ............ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 m 

AI Gabon ........................ 0 0 0 0 0 0 0 0 25 19 7 8 15 4 2 8 9 10 10 20 ~ 

> Central African Republic ....... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ::::- Congo ........................ 0 0 0 0 0 0 0 0 2 1 6 1 2 1 0 0 0 0 0 1 r;· 

!-1 Zaire ......................... 0 0 0 0 0 1 1 0 0 0 0 0 0 0 1 1 0 0 0 0 

z Ethiopia ...................... 1 0 1 1 0 6 0 0 0 0 0 0 0 1 0 1 2 0 0 2 Q 

= Kenya ........................ 0 0 0 0 0 0 1 0 1 2 2 1 1 2 0 0 0 1 1 0 ;-, 

Q Somalia ...................... 0 0 0 0 0 0 0 2 2 5 4 3 4 0 1 4 1 1 2 2 

3 Uganda ....................... 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 

c Angola ....................... 0 0 0 3 4 1 8 6 4 10 11 10 6 10 6 10 15 24 55 31 

= i" Zambia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

> Tanzania ...................... 0 0 0 0 0 0 1 0 4 5 5 0 1 0 0 0 0 0 0 0 fll 

~· Mozambique .................. 0 0 0 2 0 0 1 2 0 0 0 1 3 2 0 5 1 16 0 0 AI Burundi ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 = Cl.. Namibia ...................... 0 0 0 0 0 0 0 0 0 0 0 0 2 1 1 0 0 0 0 0 ;:. 

tD Lesotho ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 til Madagascar ................... 0 1 2 0 0 3 3 4 5 3 6 0 0 1 0 1 0 0 0 0 ~ ., South Africa .................. 0 0 0 0 1 1 3 0 0 0 0 0 1 0 0 0 6 2 2 9 

n 

AI Mauritius ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

3i Seychelles .................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 n - - - - - - - - - - - - - - - - - - - - Subtotal .................. 47 79 70 82 90 78 90 69 144 183 232 273 337 343 288 279 219 233 251 248 
Area 1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 TOTAL 

Africa -Continued 

Morocco ...................... 1 8 7 4 2 5 8 5 4 7 10 14 11 8 5 6 5 7 2 0 471 

Algeria ....................... 37 25 10 13 9 17 11 15 23 33 32 1 1 2 3 25 30 25 14 18 935 

Tunisia ....................... 6 13 12 9 16 8 10 10 11 13 15 33 21 14 17 15 6 16 10 8 361 

Libya ......................... 51 41 34 25 32 45 22 33 41 28 37 43 34 61 51 45 27 41 25 26 2009 

Egypt ........................ 33 22 26 15 12 20 34 30 24 33 45 64 82 70 45 76 54 55 58 43 978 

Western Sahara ............... 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 72 

Mauritania .................... 2 0 1 1 3 0 0 0 0 0 1 0 0 0 1 0 0 0 0 1 13 

Mali. ......................... 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 3 

Niger ......................... 0 0 0 0 0 6 0 0 0 3 3 0 1 1 0 0 0 0 0 0 23 

Chad ......................... 0 0 0 0 4 4 4 3 5 1 0 0 0 0 0 4 4 0 0 0 29 

Sudan ........................ 0 0 0 0 0 1 2 1 4 6 8 14 17 24 4 6 2 1 0 4 100 

Senegal ....................... 5 6 1 0 0 1 2 1 0 0 0 0 1 0 0 0 0 0 0 0 57 

The Gambia .................. 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 3 4 10 

Guinea-Bissau ................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 11 

Guinea ....................... 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 2 

Sierra Leone .................. 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 2 

Liberia ....................... 0 4 0 0 0 0 0 0 0 0 0 0 0 0 1 3 0 0 0 0 8 

Ivory Coast ................... 0 0 2 1 1 3 1 10 5 3 2 10 14 4 5 3 0 0 1 1 70 

Ghana ........................ 11 2 1 1 1 5 0 2 1 2 0 1 1 0 2 2 2 11 0 3 54 

Togo ......................... 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 5 

Benin ........................ 4 0 1 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 12 

Nigeria ....................... 31 55 61 45 51 33 21 24 35 22 31 26 30 24 12 17 29 44 42 47 1138 

Cameroon .................... 6 2 5 3 5 7 7 32 21 25 17 18 11 4 6 9 5 0 3 1 223 

Equatorial Guinea ............. 0 1 0 0 0 0 0 0 0 0 0 0 4 0 1 1 1 0 1 0 14 

Gabon ........................ 13 11 17 15 13 23 19 19 20 22 15 23 16 11 18 13 12 16 20 26 479 

Central African Republic ....... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 

Congo ........................ 1 2 7 4 6 4 0 0 6 11 11 5 9 4 3 9 5 10 10 7 128 

Zaire ......................... 2 1 6 3 0 4 2 1 5 1 0 3 4 4 3 1 2 1 4 1 52 

Ethiopia ...................... 1 0 3 5 3 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 28 

Kenya ........................ 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 1 1 2 3 4 25 

Somalia ...................... 0 0 1 0 1 1 0 1 0 0 1 0 3 0 2 2 1 1 2 1 48 

Uganda ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 

Angola ....................... 25 29 15 8 20 10 0 6 6 6 2 14 23 22 13 20 17 24 29 19 522 

Zambia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 3 

Tanzania ...................... 0 0 0 0 2 0 3 1 0 1 0 0 2 1 2 3 0 2 0 0 33 

Mozambique .................. 12 5 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 53 

Burundi ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 2 

Namibia ...................... 3 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 11 

Lesotho ....................... 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 

~ Madagascar ................... 1 8 1 2 4 1 0 0 0 0 0 0 0 0 0 5 3 2 0 0 56 cr South Africa .................. 15 13 10 18 5 7 8 12 9 12 8 12 10 11 10 16 32 17 17 19 286 ii" 

(II Mauritius ..................... 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 ..... 

~ Seychelles .................... 0 0 0 0 0 0 0 0 0 0 1 2 0 0 0 0 0 0 0 0 3 - - - - - - - - - - - - - - - - - - - - --

Subtotal .................. 262 249 223 176 191 208 154 208 220 231 239 284 298 265 206 284 241 280 247 235 8336 ..... 

'! 8

No exploration wells were reported for Botswana, Burkina Faso (formerly Upper Volta), Cape Verde, Comoros, Djibouti, Malawi, Rwanda, Sao Tome and Principe, Swaziland, or Zimbabwe. 
... Table 1. Exploration wells by year, 1950--89, for the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the = southwestern Pacific-Continued 

~ Area 1950 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 .. 

2. 

I'D Non-Communist Asia' c 

3 

5 4 "" Pakistan ...................... 1 0 3 0 2 2 2 9 3 9 6 4 4 3 3 4 3 6 >( 

Maldives ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ., 

Q 

.. India ......................... 2 0 0 2 4 0 3 10 5 6 7 3 0 5 0 0 0 0 0 10 ~ Bangladesh ................... 0 0 0 0 0 0 0 0 0 0 4 1 4 0 0 0 0 0 0 0 0 

~ Myanmar ..................... 0 0 0 0 0 0 0 0 2 4 3 3 15 0 0 0 0 0 0 0 

n 

AI Thailand ...................... 0 0 0 0 0 0 0 0 0 1 3 0 0 0 0 0 0 0 0 0 .. 

a: Sri Lanka ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 cr 

m Malaysia ...................... 0 1 1 4 3 10 7 8 2 2 9 6 8 3 4 0 9 12 17 22 ~ Brunei ........................ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 ra Indonesia ..................... 19 24 14 9 7 7 9 23 12 19 20 1 3 28 19 14 3 5 17 34 

:r Japan ......................... 1 6 3 25 39 40 18 45 79 72 44 98 95 55 95 105 78 67 71 49 

> South Korea .................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 

I'D 

.. Taiwan ....................... 3 0 0 0 2 5 4 6 0 5 4 7 4 5 1 5 6 8 15 15 ~- Philippines .................... 3 0 3 1 0 0 1 2 4 9 32 12 8 2 15 0 0 0 0 0 - - - - - - - - - - - - - - - - - - - - ~ Subtotal .................. 29 31 24 41 57 64 44 103 107 127 132 135 141 101 137 128 99 98 125 139 m 

c Southwestern Pacific10 a ., 

!D 

.... Papua New Guinea ............ 8 5 8 1 12 14 7 8 8 5 5 0 1 0 0 1 2 4 8 4 ::r 

I'D Oceania11 ••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ Australia ...................... 0 1 1 2 20 37 61 47 27 52 23 17 53 107 137 155 100 83 86 51 t New Zealand .................. 0 0 0 0 0 0 0 0 0 1 2 1 2 4 8 7 3 1 1 10 ii" - - - - - - - - - - - - - - - - - - - -

j Subtotal .................. 8 6 9 3 32 51 68 55 35 58 30 18 56 111 145 163 105 88 95 65 

> 3: GRAND TOTAL.............. 440 630 739 758 915 897 965 1091 1216 1254 1370 1316 1385 1329 1296 1369 1282 1205 1252 1244 ~ 

z 

0 

:II 

n 

0 

3 

3 

c 

a. 

=. 

> 

~· 

AI 

&. 

.... 

::r 

I'D 

~ 

-: ,., 

3i 

,., 
i 

i 

~ 

.... 

I.C 

Area 1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 

Non-Communist Asia9 -Continued 

Pakistan ...................... 6 4 3 3 5 5 1 4 6 11 10 13 10 14 17 26 

Maldives ..................... 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 

India ......................... 0 0 7 10 0 0 1 0 0 0 0 17 0 11 37 87 

Bangladesh ................... 0 0 0 1 0 2 5 5 2 0 0 5 2 1 0 0 

Myanmar ..................... 1 0 6 0 6 10 9 0 0 0 11 17 19 0 45 9 

Thailand ...................... 0 1 4 3 14 10 17 3 8 10 14 21 30 38 38 28 

Sri Lanka ..................... 0 0 0 0 1 0 3 0 0 0 0 2 0 0 0 0 

Malaysia ...................... 14 11 19 18 31 11 12 14 16 58 44 61 25 20 16 25 

Brunei ........................ 0 0 6 10 0 0 11 3 7 5 1 4 6 6 14 9 

Indonesia ..................... 87 138 140 169 168 184 130 115 146 154 182 224 204 267 216 208 

Japan ......................... 0 4 8 36 28 25 19 29 36 25 24 27 27 23 18 16 

South Korea .................. 0 0 1 5 0 2 0 0 0 0 2 1 0 1 0 2 

Taiwan ....................... 5 9 5 18 17 18 10 15 20 18 30 16 13 18 4 12 

Philippines .................... 2 17 8 10 7 13 8 15 18 23 23 17 13 4 3 0 - - - - - - - - - - - - - - - - Subtotal. . . . . . . . . . . . . . . . . . 115 184 207 283 277 280 227 203 259 304 341 426 349 403 408 422 

Southwestern Pacific10 -Continued 

Papua New Guinea ............ 2 2 1 6 0 3 2 1 1 0 0 14 2 4 5 5 

Oceania11 ••••••••••••••••••••• 0 2 0 0 0 0 0 0 0 3 2 0 4 0 0 0 

Australia. . . . . . . . . . . . . . . . . . . . . . 110 65 92 61 51 20 17 17 51 49 67 125 149 182 263 267 

New Zealand .................. 10 9 6 0 0 5 7 3 3 2 4 8 6 15 8 25 - - - - - - - - - - - - - - - - Subtotal.................. 122 78 99 67 51 28 26 21 55 54 73 147 161 201 276 297 

GRAND TOTAL .............. 1260 1319 1376 1340 1353 1343 1244 1280 1318 1437 1727 2535 2472 2087 1892 2272 

~o exploration wells were reported for Afghanistan, Bhutan, Nepal, or Singapore. 

~o exploration wells were reported for New Caledonia (an overseas territory of France). 11For this report, Oceania is considered to consist of Fiji, Kiribati, Nauru, Solomon Islands, Tonga, Tuvalu, Vanuatu (formerly New Hebrides), and Western Samoa. 

86 87 88 89 TOTAL 

15 9 31 20 286 

0 0 0 0 2 

49 37 51 0 364 

0 2 5 0 39 

3 3 4 0 170 

7 23 50 0 323 

0 0 0 0 6 

14 13 13 17 580 

13 12 13 0 125 

122 75 103 102 3421 

17 12 11 9 1479 

1 0 3 0 18 

13 9 13 0 358 

0 2 7 6 288 - - - - -- 254 197 304 154 7459 

3 5 15 23 195 

0 0 0 0 11 

139 167 140 63 3155 

24 0 0 5 180 - - - - -- 166 172 155 91 3541 

1805 1729 1450 1465 54657 
N Table 2. Wildcat wells by year, 1951-90, for the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the southwestern = Pacific 

""c:c [Data are from a computer tape released in January 1991 by Petroconsultants S.A., Geneva. Column denoted "Unkn" means year unknown; these wells are not plotted in the graphs] ~ 

a 

;- Area Pre-1951 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 c 

3 

m Mexico ....................... 68 8 5 3 9 8 10 9 10 10 21 21 15 0 2 0 1 0 2 01( 

"Q 

0 

.. Caribbean ~ 

s· Bahamas ...................... 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 ? 

n Cuba 1 •••••••••••••••••••••••• 11 0 1 0 3 11 29 22 22 13 4 6 1 0 6 2 0 0 1 2 AI Haiti ......................... 4 0 0 0 0 1 2 0 0 1 0 0 0 0 0 0 0 0 0 0 .. 

e: 

a' Dominican Republic ........... 2 0 0 0 0 0 0 0 4 0 2 3 0 0 0 0 0 2 0 6 II> 

AI Jamaica ....................... 0 0 0 0 0 1 0 3 0 0 0 0 0 0 0 0 0 0 0 0 ... = 

r- Barbados ..................... 1 0 0 0 2 2 1 0 0 1 0 0 0 0 0 0 9 2 0 0 ~ Lesser Antilles2 ••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 :r - - - - - - - - - - - - - - - - - - - - ~ Subtotal .................. 19 0 1 0 5 15 32 25 26 16 6 9 1 0 6 2 9 4 1 8 3 

~ ;:;- Central America3 

~ 

~ Belize ........................ 0 0 0 0 0 0 2 1 6 2 0 1 1 1 0 0 0 2 0 0 m 

c Honduras ..................... 2 0 0 0 0 0 1 1 0 0 0 0 0 1 0 2 4 1 0 1 .. Guatemala .................... 1 0 0 0 0 0 0 0 1 5 2 2 1 0 0 0 0 0 1 0 Q 

"Q 

!0 Nicaragua ..................... 5 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 2 5 

-

=- Costa Rica .................... 6 0 0 0 0 3 2 2 1 3 2 0 1 2 0 0 0 0 0 0 II> 

~ Panama ....................... 11 0 0 0 0 0 2 1 2 2 0 1 4 0 0 0 0 0 0 0 

a: - - - - - - - - - - - - - - - - - - - - Q. Subtotal .................. 25 0 0 0 0 3 7 6 10 12 4 4 7 4 0 2 4 4 3 6 ;-

m 

~ South America 

.. 

~ Colombia ..................... 174 9 7 15 21 13 13 20 34 27 37 33 18 24 23 18 20 18 21 20 

~- Venezuela .................... 808 58 52 62 63 98 83 75 122 75 33 36 14 9 1 12 5 12 3 7 

z Trinidad and Tobago .......... 31 1 5 4 6 8 9 2 9 11 7 6 7 14 7 8 3 3 9 5 Q Guyana ....................... 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 = n Suriname ..................... 2 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 6 1 4 4 Q 

French Guiana4 3 ••.•••........• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

3 

c Ecuador ...................... 39 1 1 1 4 0 0 3 0 5 9 1 0 1 1 0 0 3 4 5 

= Peru .. ~ ....................... 29 4 6 5 13 11 12 7 8 2 11 12 4 4 0 7 4 6 6 4 =: 

~ Bolivia ....................... 22 0 0 0 1 1 2 1 11 7 12 12 16 10 10 7 12 15 11 1 Ill 

jJ" Uruguay ...................... 26 0 0 0 0 1 1 0 2 1 0 0 0 0 0 0 1 0 0 0 

AI Paraguay ..................... 5 0 0 0 0 0 0 0 1 3 0 0 0 0 0 0 0 3 0 0 Q. = Brazil ........................ 22 4 4 4 2 9 2 18 28 39 46 32 39 45 38 46 45 61 56 40 

-

=- Chile ......................... 14 5 6 12 17 8 2 8 6 3 16 13 21 14 13 14 15 12 16 19 II> 

tl) Argentina ..................... 308 15 23 31 32 29 37 24 23 69 111 77 99 55 50 82 76 72 66 55 ~ -- - - - - - - - - - - - - - - - - - - -

""c:c Subtotal .................. 1481 97 104 134 159 178 161 158 244 242 282 222 218 176 144 195 187 208 196 160 AI 

n 

3i 

n 
Area 1970 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 Unkn TOTAL 

Mexico ....................... 0 0 0 0 0 0 1 21 14 5 2 4 0 0 0 0 0 0 1 0 0 0 251 

Caribbean-Continued 

Bahamas ...................... 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 5 

Cuba1 •.•••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 184 320 

Haiti ......................... 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 

Dominican Republic ........... 1 0 0 0 0 0 0 0 0 3 0 1 1 0 0 0 0 0 0 0 0 5 30 

Jamaica ....................... 1 1 0 1 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 11 

Barbados ..................... 1 2 0 0 0 0 0 0 1 0 0 0 0 0 0 5 1 0 0 1 0 31 60 

Lesser Antilles2 ••••••••••••••• 0 0 0 0 0 0 0 1 0 0 0 1 1 0 0 0 0 0 0 0 0 0 3 - - - - - - - - - - - - - - - - - - - - -

Subtotal .................. 4 4 0 1 0 0 0 4 1 3 0 2 6 0 0 5 2 0 0 3 0 220 440 

Central America3 -Continued 

Belize ........................ 0 0 5 2 1 4 0 2 0 2 0 3 2 2 0 3 0 0 0 0 2 0 44 

Honduras ..................... 0 1 3 3 0 1 0 0 2 0 2 0 0 1 0 0 0 0 0 0 0 0 26 

Guatemala .................... 3 2 3 3 1 2 3 4 0 1 3 7 9 4 1 4 1 0 3 1 0 0 68 

Nicaragua ..................... 8 3 0 0 2 3 0 2 3 0 0 0 0 0 0 0 0 0 0 0 0 1 36 

Costa Rica .................... 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 25 

Panama ....................... 0 1 0 0 2 0 0 0 1 1 0 0 0 0 0 0 0 0 0 3 0 0 31 - - - - - - - - - - - - - - - - - - - - - - -

Subtotal .................. 11 7 11 8 6 11 3 8 6 4 5 10 11 7 1 8 1 1 3 4 2 1 230 

South America-Continued 

Colombia ..................... 19 18 19 18 16 10 12 14 17 22 28 55 63 23 37 49 41 57 79 52 46 34 1294 

Venezuela .................... 1 2 18 18 10 5 11 4 9 20 105 118 119 37 16 13 9 4 5 3 1 13 2169 

Trinidad and Tobago .......... 7 15 14 9 7 7 10 6 4 3 2 6 9 2 1 2 0 1 1 3 1 26 ;291 

Guyana ....................... 0 1 0 0 2 3 1 0 0 0 0 0 2 0 0 0 0 0 0 0 0 1 13 

Suriname ..................... 4 1 0 0 0 1 0 0 1 0 0 1 3 6 0 3 0 0 0 1 0 11 51 

French Guiana 4 .••••.•••••.••• 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 2 

Ecuador ...................... 11 13 18 8 5 1 1 4 3 9 7 1 5 7 1 2 5 8 15 11 3 8 224 

Peru .......................... 11 4 12 13 15 38 10 11 7 1 4 7 7 14 18 3 3 6 2 3 0 5 349 

Bolivia ....................... 4 3 6 4 5 6 12 8 9 8 4 12 7 4 2 7 1 3 3 5 1 0 265 

Uruguay ...................... 0 0 0 0 0 0 2 0 1 1 0 0 0 0 0 0 2 2 0 0 0 24 64 

Paraguay ..................... 0 11 5 0 0 1 1 3 3 1 0 1 1 0 0 0 1 1 1 1 0 0 43 

Brazil ........................ 42 56 52 58 53 70 76 63 82 105 119 126 152 165 151 107 85 84 76 60 45 11 2418 

Chile ......................... 17 18 32 20 27 19 18 5 3 1 4 15 5 8 7 1 10 9 8 14 9 62 546 

Argentina ..................... 98 125 93 118 91 63 68 90 55 47 61 74 69 114 120 137 72 71 67 70 59 58 3154 - - - - - - - - - - - - - - - - - - - - - - --

Subtotal. . . . . . . . . . . . . . . . . . 214 267 269 266 231 225 222 208 195 218 334 416 442 380 353 324 229 246 257 223 165 253 10883 

;t 1 Data for Cuba for 1960-90 are incomplete. 

cr 2

For this report, the Lesser Antilles are considered to consist of the islands from Grenada to St. Thomas, except Barbados, which is listed separately. ;-

fll 3

No wildcat wells were reported for El Salvador. ..... 4

French Guiana is listed separately although it is an overseas department of France. ~ 

to.) 

..... 
Table 2. Wildcat wells by year, 1951-90, for the Caribbean, latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific-Continued 

..., Area Pre-1951 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 ..., 

""C' Western Europe5 

1 

a Norway ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 4 10 15 

;- Svalbard6 c ••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 

3 Sweden ....................... 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 2 0 

"" Denmark7 ••••••••••••••••••••• 7 4 4 3 0 0 0 0 9 2 0 0 0 0 0 0 3 2 6 2 >C 

"'CC 

Q Ireland ....................... 0 0 0 0 0 0 0 0 0 0 0 0 2 4 0 0 0 0 0 0 i United Kingdom .............. 129 1 1 5 6 11 6 4 17 10 11 9 3 7 6 28 31 41 35 52 a· 

~ Netherlands ................... 35 12 7 8 11 9 5 7 6 9 4 2 4 2 23 33 9 2 15 29 

t""' Belgium ...................... 0 0 0 0 0 0 0 0 0 0 1 0 2 0 1 0 0 0 0 0 ~ West Germany ................ 188 74 73 75 105 96 114 97 115 87 73 47 48 18 57 33 54 35 50 43 s= 

r France ........................ 112 39 42 33 36 53 65 82 114 125 106 102 101 100 77 59 31 26 13 24 

~ Switzerland ................... 5 0 0 1 0 0 0 0 1 0 3 2 1 2 2 3 0 0 0 0 ,... Austria ....................... 12 0 0 0 0 0 2 7 4 13 15 12 9 11 11 12 13 9 16 20 ~ Italy .......................... 41 3 7 25 20 32 42 80 66 91 101 85 109 90 79 46 66 30 28 48 :r 

> Greece ....................... 3 0 0 0 0 0 1 1 1 0 0 6 5 7 2 2 0 10 0 0 

3 

tD Yugoslavia .................... 15 3 1 2 1 3 2 3 2 6 3 3 5 6 5 6 5 8 5 6 "'I 

~· Portugal ...................... 12 1 1 3 2 3 1 2 5 8 1 1 1 4 0 0 0 0 0 0 

~ Spain ......................... 45 2 3 3 7 3 11 12 12 20 10 15 16 23 10 15 18 12 17 10 

Malta ......................... 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 

"" - - - - - - - - - - - - - - - - - - - - c 

a Subtotal .................. 604 139 139 158 188 211 249 295 352 372 328 284 306 274 273 237 233 181 197 249 "'CC 

!D 

.... Middle East ::r 

tD 

~ Turkey ....................... 16 3 5 2 2 1 0 8 9 19 20 35 18 12 14 26 28 18 27 13 

a: Cyprus ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0.. 

;- Syria ......................... 9 1 0 0 0 0 1 0 2 4 3 1 4 2 0 0 1 0 0 0 

j Lebanon ...................... 1 0 0 1 0 0 0 0 0 0 1 1 0 2 0 0 1 0 0 0 

> 

Israel ......................... 1 0 0 0 2 6 9 9 8 5 4 6 5 3 8 11 11 7 9 5 

-

"'I Jordan ........................ 0 0 0 0 0 0 0 1 1 3 1 0 0 1 0 2 0 0 0 0 ~· Iraq .......................... 52 1 1 4 1 2 2 5 4 5 9 8 0 0 0 0 0 0 0 2 

z Iran .......................... 48 2 0 0 2 0 1 1 2 4 3 9 8 6 6 9 17 21 17 13 Q 

= Saudi Arabia .................. 12 2 0 0 0 0 1 1 1 0 0 0 0 3 2 2 3 8 7 4 

n Kuwait ....................... 2 1 1 0 1 1 1 0 1 3 0 1 4 12 1 2 5 1 0 0 Q 

3 Former Neutral Zone8 ••••••••• 2 0 2 1 3 2 1 0 0 0 1 3 7 3 0 1 3 2 0 0 3 

c Bahrain ....................... 1 0 0 0 0 0 0 0 0 1 0 1 1 0 0 1 1 0 0 0 

= Qatar ......................... 1 0 1 2 0 1 1 0 0 0 3 1 5 4 3 1 1 4 3 2 !i 

> Oman ........................ 0 0 0 0 0 1 0 6 3 8 8 1 3 3 4 1 9 2 3 6 Ill 

~· Yemen ....................... 0 0 0 0 0 0 0 0 0 0 0 0 3 0 1 1 0 0 0 0 I» Abu Dhabi9 ................... 0 1 0 0 1 0 1 1 1 0 0 0 4 1 4 3 4 5 7 8 

= 0.. AI Fujayrah9 .................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 .... 

::r Dubai9 ••.•••••••••••••••••••• 0 0 1 0 0 0 0 0 0 0 0 0 0 0 2 1 1 0 1 0 tD 

c;ll Ra's a1 Khaymah9 ••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 ~ Ajman9 ••••••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

-: Sharjah9 •••••....•••••••••.••• 0 0 0 0 0 0 0 0 1 0 0 0 0 1 1 1 1 1 0 0 n 

Si Umm a1 Qaywayn9 ............ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 n - - - - - - - - - - - - - - - - - - - - Subtotal .................. 145 11 11 10 12 14 18 32 33 52 53 67 62 53 46 63 87 69 74 56 
Area 1970 71 72 73 74 75 76 77 787 79 80 81 82 83 84 85 86 87 88 89 90 Unkn TOTAL 

Western Europe5 -Continued 

Norway ....................... 12 12 12 15 15 15 20 10 15 15 20 21 31 27 30 25 25 17 19 14 23 6 430 

Svalbard6 •••••••••••••.••••••• 0 1 2 2 2 1 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 12 

Sweden ....................... 0 4 10 13 14 27 6 7 34 11 12 18 15 11 11 15 0 5 12 12 26 12 279 

Denmark7 ••.•••••••••••••••••• 3 2 0 4 2 3 8 9 3 2 6 2 5 10 6 13 2 3 2 4 2 1 134 

Ireland ....................... 0 3 2 4 4 6 5 6 16 8 2 8 4 6 7 6 7 4 4 4 4 0 116 

United Kingdom .............. 29 33 34 56 68 79 63 74 36 38 34 54 81 82 123 120 128 85 103 105 142 43 2023 

Netherlands ................... 24 28 22 20 17 22 21 25 22 19 28 28 44 40 39 42 33 29 26 29 35 19 844 

Belgium ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 7 

West Germany ................ 28 26 25 28 29 25 28 27 30 30 25 34 41 30 32 28 22 14 14 6 10 96 2110 

France ........................ 13 8 10 12 9 11 14 14 17 22 21 39 37 23 36 50 71 26 35 33 23 32 1896 

Switzerland ................... 0 0 0 1 0 0 0 1 1 0 1 1 3 0 0 0 0 0 0 1 0 0 29 

Austria ....................... 15 25 16 15 18 33 20 38 20 22 17 20 20 18 20 11 11 13 17 6 10 62 613 

Italy .......................... 34 42 47 30 23 28 29 23 61 40 53 73 76 49 60 52 85 72 70 29 28 105 2198 

Greece ....................... 2 1 2 4 3 0 1 5 4 5 5 8 11 7 7 4 2 3 4 3 0 10 129 

Yugoslavia .................... 6 10 1 16 10 6 6 7 18 16 13 10 16 13 13 25 13 4 5 10 6 33 347 

Portugal ...................... 0 0 0 0 3 7 9 1 0 2 0 1 3 2 0 1 0 0 3 0 2 0 79 

Spain ......................... 8 12 6 17 8 15 19 16 18 14 22 22 11 18 14 17 16 12 8 8 4 7 556 

Malta ......................... 0 0 3 1 0 0 0 0 0 0 1 0 2 0 0 1 0 0 0 0 0 0 9 - - - - - - - - - - - - - - - - - - - - - - -- Subtotal. . . . . . . . . . . . . . . . . . 174 207 192 238 225 278 249 264 295 244 260 339 400 336 398 410 415 288 322 264 315 429 11811 

Middle East-Continued 

Turkey ....................... 36 18 23 29 33 43 41 24 22 10 23 19 30 24 16 20 23 27 34 32 24 9 836 

Cyprus ....................... 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 

Syria ......................... 0 0 0 0 1 2 12 5 11 4 2 3 3 1 4 5 16 5 12 3 7 16 140 

Lebanon ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7 

Israel ......................... 8 4 5 2 1 9 8 15 5 0 7 6 8 10 4 1 3 3 1 2 3 13 227 

Jordan ........................ 2 4 2 0 1 0 0 0 1 0 0 0 0 2 4 0 1 2 6 3 1 0 38 

Iraq .......................... 0 1 0 3 3 0 3 2 2 1 0 0 0 0 0 0 0 0 0 0 0 3 114 

Iran .......................... 14 11 9 19 21 21 19 11 12 5 1 0 1 0 0 0 0 0 3 0 1 1 318 

Saudi Arabia .................. 4 6 7 4 6 5 3 4 5 6 5 2 3 1 2 0 0 0 0 2 4 1 116 

Kuwait ....................... 2 1 1 1 0 0 1 1 0 0 0 0 0 0 2 1 0 0 1 0 0 3 51 

Former Neutral Zone8 .•••••••• 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 32 

Bahrain ....................... 0 0 1 1 0 1 0 0 1 0 1 0 0 0 0 0 2 0 0 0 0 1 14 

Qatar ......................... 2 3 3 2 0 0 1 1 1 4 1 0 2 1 0 0 0 1 6 2 3 2 68 

Oman ........................ 3 11 14 12 4 9 11 8 10 14 17 16 21 18 37 26 33 24 20 18 31 1 416 

Yemen ....................... 0 0 2 0 0 0 1 1 1 2 1 4 3 0 3 5 17 9 4 2 4 3 67 

Abu Dhabi9 •••••••••••••.••••• 13 9 1 9 10 6 6 2 5 7 1 6 8 10 7 9 3 0 1 1 3 0 158 

AI Fujayrah9 •••••••••••••••••• 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 3 

Dubai9 •••••••••.••••••••••••• 0 1 1 1 0 0 4 1 0 2 2 1 3 0 6 5 1 2 2 1 1 0 40 

~ Ra's al Khaymah9 ••••••••••••• 0 1 1 0 0 0 1 1 0 0 1 0 1 2 2 2 1 0 1 0 0 0 16 I» Ajman9 c:r ••.•••••••••••••••••••• 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 if Sharjah9 ••••••••••••••••.•.••• 0 1 1 0 1 0 0 0 1 0 2 1 1 2 2 2 0 1 0 0 0 0 21 ... Umm a1 Qaywayn9 •••••••••••• 0 1 0 0 0 0 2 1 1 0 0 1 1 1 0 0 1 0 0 0 0 0 10 ~ - - - - - - - - - - - - - - - - - - - - - - -- Subtotal .................. 85 72 71 83 81 96 113 78 78 55 65 59 86 73 89 76 101 74 91 66 82 53 2695 

~ 

~ 5

No wildcat wells were reported for Andorra, Finland, Iceland, Liechtenstein, Luxemburg, or Monaco. Data for Yugoslavia are incomplete. 6

Svalbard (or Spitsbergen) is a group of islands in the Arctic Ocean north of and belonging to Norway. 7

Data for Denmark include five wildcat wells drilled in Greenland-one drilled in 1976 and four drilled in 1977. 

~e former Neutral Zone was located between Kuwait and Saudi Arabia. 9

0ne of the seven United Arab Emirates. 
Table 2. Wildcat wells by year, 1951-90, for the Caribbean, latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific-Continued to.J 

.a:. 

Area Pre-1951 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 ., 

I'D Mrica10 ... 

c; 

tD Morocco ...................... 8 9 6 16 14 11 8 5 3 4 3 14 13 2 8 6 11 9 9 15 c 

3 

m Algeria ....................... 4 8 8 8 23 25 35 29 39 37 53 63 66 64 46 19 14 18 13 30 >< Tunisia ....................... 14 0 4 7 15 4 5 4 5 5 0 1 7 4 5 6 7 10 5 3 "'g 

... 

CS" Libya ......................... 0 0 0 0 0 0 0 7 24 31 72 91 112 145 134 114 60 40 76 73 ~ Egypt ........................ 117 1 0 0 3 5 4 6 7 3 8 10 8 10 9 9 14 7 23 25 =· ,:s Western Sahara ............... 0 0 0 0 0 0 0 0 0 0 1 9 14 7 4 3 4 5 0 1 

t""l 

AI Mauritania .................... 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 2 ... 

s: Mali. ......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C" 

I'D Niger ......................... 0 0 0 0 0 0 0 0 0 0 0 0 6 1 2 0 0 0 0 0 AI Chad ......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ,:s 

r-

~ Sudan ........................ 0 0 0 0 0 0 0 0 0 0 0 1 3 2 0 0 0 0 0 0 

:r Senegal ....................... 0 0 0 0 0 1 1 0 3 7 6 7 2 0 0 0 2 5 2 3 

> The Gambia .................. 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 3 Guinea-Bissau ................. 0 0 0 0 0 0 0 0 0 0 1 3 0 0 0 0 0 0 2 3 I'D 

... 

;::;· Guinea ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .!J Sierra Leone .................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ m Liberia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

Ivory Coast ................... 0 0 0 0 0 0 0 2 3 1 1 1 0 0 0 0 0 0 0 0 c 

... 

Q Ghana ........................ 0 0 0 0 0 0 1 3 0 0 0 0 0 0 0 0 0 2 0 0 "'g 

!D Togo ......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ;:. 

I'D Benin ........................ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 ~ Nigeria ....................... 0 0 1 1 3 6 2 1 17 35 23 17 6 17 32 60 66 81 39 22 a: 

Q. Cameroon .................... 0 0 0 3 4 0 2 2 1 1 0 0 0 0 0 1 0 4 0 1 tD 

m Equatorial Guinea ............. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 5 0 

el Gabon ........................ 0 3 9 9 5 8 4 11 24 19 8 8 15 5 1 8 8 10 11 21 , ... 

> Central African Republic ....... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

- Congo ........................ 0 0 0 0 0 0 0 1 1 1 6 1 2 1 0 0 0 0 0 1 ... 

;::;· 

.!J Zaire ......................... 0 0 0 0 0 1 1 0 0 0 0 0 0 0 1 3 0 0 0 0 

z Ethiopia ...................... 7 0 0 0 1 8 7 0 0 0 0 0 0 1 0 1 2 0 0 2 Q 

Kenya ........................ 0 0 0 0 0 0 0 0 0 0 2 1 1 1 1 0 0 1 1 0 :s 

n 

Q Somalia ...................... 0 0 0 0 0 0 1 4 7 6 3 3 2 3 1 3 1 1 2 2 

3 Angola ....................... 0 0 0 3 4 1 1 5 4 7 24 10 3 9 4 16 8 15 44 27 3 

c Zambia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 :s a· Tanzania ...................... 0 0 0 0 0 0 1 1 0 1 0 0 1 0 0 0 0 0 0 0 

Wl > Mozambique .................. 0 0 0 2 0 0 1 2 0 0 0 1 3 1 0 5 1 15 0 0 ~· Zimbabwe .................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

:s 

AI Burundi ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Q. 

... Namibia ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ::r Lesotho ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I'D 

fll Madagascar ................... 3 0 2 3 0 1 3 3 5 3 6 0 0 1 1 1 0 0 0 0 ~ South Africa .................. 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 2 4 3 11 -: 

n Mauritius ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

n 

3i Seychelles .................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - - - - - - - - - - - - - - - - - - - -

Subtotal .................. 154 21 30 52 72 71 77 86 143 161 218 242 265 275 249 256 200 228 236 243 
Area 1970 71 72 73 74 75 76 77 787 79 80 81 82 83 84 85 86 87 88 89 90 Unkn TOTAl 

Africa10 -Continued 

Morocco ...................... 1 7 6 3 4 4 6 2 4 7 10 11 6 4 4 6 4 7 1 0 1 154 426 

Algeria ....................... 39 26 9 9 15 17 28 23 8 4 2 1 0 3 3 4 3 3 10 15 9 9 842 

Tunisia ....................... 5 11 13 9 16 8 8 8 7 12 16 33 21 11 12 12 7 12 9 8 7 16 372 

Libya ......................... 47 41 31 25 18 42 24 26 36 21 21 34 27 40 37 22 14 16 13 15 4 58 1591 

Egypt ........................ 35 23 20 16 14 19 35 43 29 30 34 49 47 40 31 57 56 49 45 31 22 28 1022 

Western Sahara ............... 1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 14 65 

Mauritania .................... 2 0 1 1 3 0 0 0 0 0 1 0 0 0 1 0 0 0 0 1 0 0 14 

Mali. ......................... 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 0 0 3 

Niger ......................... 0 0 0 0 0 7 0 0 0 3 3 0 2 0 0 0 0 0 0 0 2 0 26 

Chad ......................... 0 0 0 0 4 2 4 3 5 1 0 0 0 0 0 4 4 0 0 2 1 0 30 

Sudan ........................ 0 0 0 0 0 1 2 1 4 5 2 11 11 11 3 6 2 1 0 4 0 0 70 

Senegal ....................... 5 5 1 0 0 1 2 1 0 0 0 0 1 0 1 0 0 0 1 2 0 13 72 

The Gambia .................. 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 3 

Guinea-Bissau ................. 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 3 0 14 

Guinea ....................... 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 

Sierra Leone .................. 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 2 

Liberia ....................... 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 7 

Ivory Coast ................... 0 0 2 1 1 0 0 3 5 3 1 8 11 2 7 1 0 0 1 0 0 0 54 

Ghana ........................ 9 1 1 1 1 4 0 1 1 1 0 2 1 0 0 2 0 1 0 3 1 0 36 

Togo ......................... 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 3 

Benin ........................ 4 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8 

Nigeria ....................... 24 53 55 41 52 32 16 28 31 27 33 26 24 21 13 17 17 17 25 25 25 5 1036 

Cameroon .................... 6 2 4 2 3 7 4 24 13 13 18 17 9 3 5 4 3 0 0 0 0 0 156 

Equatorial Guinea ............. 0 1 0 0 0 0 0 0 0 0 0 0 4 0 1 1 1 0 1 0 0 0 15 

Gabon ........................ 12 11 17 13 15 17 14 16 11 19 15 22 15 12 15 13 7 5 18 25 21 10 510 

Central African Republic ....... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 

Congo ........................ 2 2 7 6 6 4 0 0 5 7 9 8 9 4 3 7 3 8 5 3 8 2 122 

Zaire ......................... 0 1 7 4 0 4 2 1 2 1 0 3 4 4 4 1 1 0 3 1 0 0 49 

Ethiopia ...................... 1 0 2 5 3 0 0 1 0 0 0 0 0 2 1 1 0 0 0 0 1 6 52 

Kenya ........................ 0 2 0 0 0 1 2 0 1 0 0 2 1 0 0 1 1 0 3 4 1 0 27 

Somalia ...................... 0 0 0 1 1 1 1 1 0 0 1 0 3 0 2 2 0 1 2 0 3 0 58 

Angola ....................... 18 30 11 6 28 9 1 5 4 3 3 11 18 22 11 17 16 16 17 10 16 29 486 

Zambia ....................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 2 

Tanzania ...................... 0 0 0 0 2 0 2 0 0 1 0 0 2 2 2 2 1 2 0 0 2 0 22 

Mozambique .................. 10 6 2 1 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 52 

Zimbabwe .................... 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 

Burundi ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 2 

Namibia ...................... 3 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 6 

Lesotho ....................... 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 

';} Madagascar .............. · ..... 1 8 1 2 4 1 0 0 0 0 0 0 0 8 4 4 3 2 0 0 1 0 71 cr South Africa .................. 15 18 11 17 2 15 15 11 10 6 8 3 4 10 12 14 21 14 15 19 14 17 293 (i' 

Ill Mauritius ..................... 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 ... 

~ Seychelles .................... 0 0 0 0 0 0 0 0 0 0 1 2 0 0 0 0 0 0 0 0 0 0 3 - - - - - - - - - - - - - - - - - - - - - - -- Subtotal. . . . . . . . . . . . . . . . . . 242 252 202 166 194 199 166 199 176 166 178 243 222 199 173 204 167 157 171 168 142 363 7628 t.,J 

1.11 ~o wildcat wells were reported for Botswana, Burkina Faso (formerly Upper Volta), Cape Verde, Comoros, Djibouti, Malawi, Rwanda, Sao Tome and Principe, Swaziland, Uganda, or Zambia. 
~ 

N Table 2. Wildcat wells by year, 1951-90, for the Caribbean, latin America, Western Europe, the Middle East, Africa, non-Communist Asia, and the southwestern 

Pacific-Continued 

"'CC 

~ Area Pre-1951 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 a 

ii" 

Non-Communist Asia11 c 

3 

m Mghanistan ................... 0 0 0 0 0 0 0 0 0 0 >C ., 0 1 1 4 4 0 0 0 0 0 

0 

.. Pakistan ...................... 21 0 4 0 1 2 3 10 12 8 2 2 2 3 4 2 3 2 4 2 ~ Maldives ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 s· India ......................... 4 0 0 2 0 0 1 2 4 3 7 3 8 5 8 13 8 6 9 2 :? 

" Bangladesh ................... 4 0 0 1 0 1 0 0 1 2 5 1 2 1 0 1 0 1 0 2 .. Myanmar ..................... 2 0 0 0 0 0 0 0 1 4 0 0 3 0 0 0 0 0 0 0 a: 

cr Thailand ...................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 m Sri Lanka ..................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 :? 

r- Malaysia ...................... 20 1 5 4 2 7 4 4 1 1 2 5 5 2 3 0 4 11 12 22 ~ ;· Brunei ........................ 14 1 0 1 1 4 0 1 0 1 0 1 1 1 0 0 1 0 2 4 

> Indonesia ..................... 56 5 5 2 8 7 4 7 5 6 5 3 3 8 15 6 6 8 19 28 

3 

I'D Japan ......................... 0 0 0 0 0 0 0 0 1 3 1 5 0 3 3 3 3 4 3 6 .. 

~· South Korea .................. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 1 0 

Taiwan ....................... 7 0 0 0 0 1 1 0 2 1 0 0 1 0 4 3 7 8 5 10 ~ Philippines .................... 20 0 3 1 0 0 1 3 4 13 17 14 10 3 16 0 0 0 0 0 m - - - - - - - - - - - - - - - - - - - - c 

a Subtotal. ................. 148 7 17 11 12 22 14 27 31 42 40 35 39 26 57 28 32 46 55 78 ., 

!D Southwestern Pacific12 ... 

:::r 

I'D 

~ Papua New Guinea ............ 29 0 1 0 0 5 2 2 4 2 2 0 1 1 1 1 0 4 8 4 

a: 

a. Australia ...................... 206 1 2 3 5 32 38 32 30 34 19 17 68 101 132 145 90 78 74 91 

ii" New Zealand .................. 52 0 1 0 0 2 2 2 0 3 1 3 3 4 9 6 3 5 4 8 m Fiji .......................... 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 J - - - - - - - - - - - - - - - - - - - -

~ Subtotal .................. 287 1 4 3 5 39 42 36 34 39 22 20 72 106 142 152 93 87 86 103 

~· 

z 

0 GRAND TOTAL .............. 2931 284 311 371 462 561 610 674 883 946 974 904 985 914 919 935 846 827 850 904 :I 

n 

0 

3 

3 

c 

:I 

~ 

> fl) jJ. 

! 

a. 

... 

:::r 

I'D 

~ 

~ 9i 

1"1 
';} 

c::r 

fi 

~ 

N 

...... 

Area 1970 71 72 73 74 75 76 77 787 79 80 81 82 83 84 85 86 87 88 89 90 Unkn TOTAL 

Non-Communist Asia11-Continued 

i\fgharristan ................... 1 1 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 7 22 

Pakistan ...................... 3 0 4 3 6 4 2 2 3 4 2 8 3 10 18 15 15 8 19 18 9 11 254 

Maldives ..................... 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 

India ......................... 5 2 4 6 4 6 17 15 16 11 10 15 5 20 28 21 33 35 32 45 72 91 578 

Bangladesh ................... 0 0 0 0 0 0 6 3 1 0 1 2 2 0 0 0 0 1 4 2 0 0 44 

Myanmar ..................... 0 0 3 2 7 8 10 0 0 1 0 5 4 4 5 5 0 2 3 2 2 ' 2 75 

Thailand ...................... 0 1 4 3 13 6 16 0 1 1 3 12 12 23 11 8 2 14 12 2 9 0 155 

Sri Lanka ..................... 0 0 0 0 1 1 3 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 7 

Malaysia. . . . . . . . . . . . . . . . . . . . . . 44 22 21 22 11 23 5 11 18 36 22 26 10 5 5 11 2 6 7 16 26 16 480 

Brunei ........................ 2 1 5 5 1 13 9 3 6 3 1 3 6 3 9 3 2 2 5 4 6 1 126 

Indonesia .. . .. .. .. .. .. .. .. .. . . 84 135 117 145 150 131 106 79 95 113 117 128 136 150 122 119 68 54 93 69 72 95 2584 

Japan ......................... 0 4 7 13 19 23 16 18 21 14 9 9 8 7 9 11 12 7 8 9 6 3 268 

South Korea .................. 0 0 0 5 0 2 0 0 0 0 0 0 0 1 0 0 0 1 2 1 2 0 21 

Taiwan ....................... 5 7 3 15 14 16 8 9 7 9 9 6 0 6 4 5 3 1 0 2 0 43 222 

Philippines .................... 0 6 9 10 8 12 8 13 13 18 23 13 14 3 1 0 0 3 6 5 4 14 288 - - - - - ----- - - - - - - - - - - - - -- Subtotal. .. .. . . . . . . . .. . . . . 144 179 178 229 235 245 207 154 181 210 197 229 200 232 212 198 137 134 191 175 208 283 5125 

Southwestern Pacific12-Continued 

Papua New Guinea ............ 2 2 1 5 2 3 2 1 1 0 1 0 1 1 4 3 2 3 3 10 14 1 129 

Australia. . . . . . . . . . . . . . . . . . . . . . 93 57 73 50 42 19 14 16 43 43 56 100 149 139 152 187 105 155 128 88 115 84 3106 

New Zealand .................. 10 10 9 2 1 5 6 2 8 1 4 5 2 7 17 17 16 10 9 5 5 2 261 

Fiji .......................... 0 0 0 0 0 0 0 0 0 0 2 1 4 0 0 0 0 0 0 0 0 0 7 - - - - - - - - - - - - - - - - - - - - - - - Subtotal. . .. .. .. . .. .. .. . .. 105 69 83 57 45 27 22 19 52 44 63 106 156 147 173 207 123 168 140 103 134 87 3503 

GRAND TOTAL .............. 979 1057 1006 1048 1017 1081 983 955 998 949 1104 1408 1523 1374 1399 1432 1175 1068 1176 1006 1048 1689 42566 

11No wildcat wells were reported for Bhutan, Nepal, or Singapore. 12No wildcat wells were reported for New Caledonia (an overseas territory of france), Kiribati, Nauru, Solomon Islands, Tonga, Tuvalu, Vanuatu (formerly New Hebrides), or Western Samoa. 
Table 3. Regional distribution of total and offshore wildcat wells drilled through 1990 and discoveries in terms of 

estimated ultimate recovery 

[Drilling data are from a computer tape released in January 1991 by Petroconsultants S.A., Geneva (see table 2). Drilling data for Mexico, India, and some 

countries in the Middle East are known to be incomplete. Oil and gas data are from a computer tape released in January 1991 by Petroconsultants and are 

supplemented by field estimates from the Dallas Field Office of the Energy Information Administration (written commun., November 1990). BBO, billion 

(X 109

) barrels of oil; TCF, trillion (X 1012) cubic feet] 

Total Offshore 

Wildcat Oil Gas Wildcat Oil Gas 

wells (BBO) (TCF) wells (BBO) (TCF) 

Mexico ....................... 251 61.6 38.5 17 22.3 13.9 

Caribbean ..................... 440 .109 .166 20 .021 .005 

Central America ............... 230 .068 .001 66 0 0 

South America ................ 10,883 135 180 1,430 24.4 52.6 

Western Europe* .............. 11,464 58 467 3,310 52.2 286 

Middle East. .................. 2,695 712 1,410 338 126 441 

Africa ........................ 7,628 120 305 2,007 29.7 48.4 

Non-Communist Asia .......... 5,125 49.3 322 2,197 21.5 200 

Southwestern Pacific ........... 3,503 6.58 98.7 619 5.43 70.1 

Total study area .......... 42,219 1,141.657 2,821.367 10,004 281.551 1,112.005 

*Data for Western Europe exclude data for Yugoslavia, which are incomplete. 

28 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
Table 4. Year of first discovery and cumulative recoverable oil and gas discoveries through 1990 in the 99 

significant petroleum provinces in the study area 

[The study area is the world outside the United States, Canada, Eastern Europe, and Communist areas of Asia. Each significant 

province has at least one field containing 100 million barrels of recoverable oil. Data are from a computer tape released in January 1991 

by Petroconsultants S.A., Geneva, and are supplemented by field estimates from the Dallas Field Office of the Energy Information 

Administration (written commun., November 1990). Data for oil discoveries in four areas are graphed in figures 9-12] 

Petroleum province, country Year of first 

discovery 

Mexico 

Tampico-Misantla Basin ...................... ; . . 1901 

Salina Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1904 

Tamaulipas Arch................................ 1909 

Cantarell Complex (Campeche Shelf) . . . . . . . . . . . . . 1948 

Total .......................................................... . 

South America (fig. 9) 

Progreso Basin, Peru and Ecuador................ 1863 

Eastern Venezuela Basin, Trinidad and Tobago 

and Venezuela . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1867 

Talara Basin, Peru.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1875 

Southern Range Uplift, Trinidad and Tobago...... 1912 

Maracaibo Basin, Venezuela . . . . . . . . . . . . . . . . . . . . . 1914 

San Jorge Basin, Argentina . . . . . . . . . . . . . . . . . . . . . . 1916 

Middle Magdalena Basin, Colombia . ... . . . . . . . . . . . 1918 

Catatumbo Basin, Colombia...................... 1920 

Falcon Basin, Venezuela......................... 1921 

Neuquen Basin, Argentina . . . . . . . . . . . . . . . . . . . . . . . 1922 

Sub-Andean Zone, Argentina, Bolivia, and Peru... 1926 

Serrania Interior Oriental Belt, Venezuela . . . . . . . . . 1928 

Greater Furrial Trend, Venezuela................. 1929 

Cuyo Basin, Argentina. . . . .. .. .. .. . . .. . . . . . . .. .. . 1932 

Reconcavo Basin, Brazil......................... 1939 

Llanos Basin, Colombia .. .. .. .. .. .. . . . . . . .. .. .. . 1948 

Barinas-Apure Basin, Colombia and Venezuela.... 1948 

Putumayo Basin, Colombia .. .. .. .. . . . . . . .. .. .. . . 1949 

Austral Basin, Argentina. .. .. . . . . . . . . .. .. .. .. .. .. 1949 

Upper Magdalena Basin, Colombia . . . . . . . . . . . . . . . 1950 

Sergipe-Alagoas Basin, Brazil.................... 1957 

Napo Basin, Ecuador............................ 1967 

Ariari-Apiay Block, Colombia.................... 1969 

Maranon Basin, Peru . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1971 

Potiguar Basin, Brazil . . . . . . . .. .. .. .. .. .. .. . . . . . . 1973 

Campos Basin, Brazil............................ 1975 

Santos Basin, Brazil............................. 1979 

Total .......................................................... . 

Oil, 

cumulative 

recoverable 

discoveries 

through 1990, 

in barrels x 106 

21,687 

24,034 

291 

15,035 

61,047 

152 

25,428 

2,442 

288 

59,667 

3,893 

2,379 

473 

371 

2,668 

289 

922 

9,253 

1,484 

1,608 

2,413 

1,671 

370 

759 

968 

736 

3,748 

255 

1,163 

428 

10,005 

120 

133,953 

Gas, 

cumulative 

recoverable 

discoveries 

through 1990, 

in cubic feet x 109 

5,261 

17,782 

0 

8,015 

31,058 

504 

25,911 

2,629 

356 

17,370 

6,491 

3,097 

922 

395 

25,895 

16,653 

2,358 

6,918 

356 

2,001 

71 

13 

1,261 

12,676 

243 

1,379 

659 

221 

78 

747 

11,654 

333 

141,191 

Tables 1-6 29 
Table 4. Year of first discovery and cumulative recoverable oil and gas discoveries through 1990 in the 99 

significant petroleum provinces in the study area-Continued 

Petroleum province, country Year of first 

discovery 

Western Europe1 (fig. 10) 

Po Basin, Italy ................................. 1866 

Northwest German Basin, Germany, Denmark, 

and Netherlands ............................... 1874 

Anglo-Paris Basin, France and United Kingdom ... 1895 

Carpathian Flysch Zone, Austria .................. 1930 

Anglo-Dutch Basin, Netherlands and 

United Kingdom .............................. 1939 

Aquitaine Basin, France ......................... 1939 

lbleian Platform, Italy and Malta ................. 1952 

Caltanissetta Basin, Italy ......................... 1956 

North Sea Graben, United Kingdom, Norway, 

Denmark, Germany, and Netherlands ........... 1966 

Vestland Arch, Norway and United Kingdom ...... 1968 

Catalano-Balearic Basin, Spain ................... 1970 

North Aegean Sea Basin, Greece ................. 1971 

Mid North Sea High, United Kingdom ............ 1971 

Norwegian-Danish Basin, Norway ................ 1972 

Adriatic Basin, Italy (and E. Europe) ............. 1972 

East Shetland Platform, United Kingdom .......... 1975 

West Shetland Basin, United Kingdom ............ 1977 

Horda Platform, Norway ......................... 1979 

Kristiansund-Bodo Fault Complex, Norway ........ 1981 

Trondelag Platform, Norway ..................... 1984 

Voting Basin, Norway ........................... 1985 

Total ........................................................... 

Middle East 

Zagros Fold Belt, Iran, Iraq, Syria, and Turkey .... 1903 

Arabian Basin, Iran, Iraq, Saudi Arabia, 

Kuwait, former Neutral Zone,2 Bahrain, Qatar, 

Syria, Oman, and United Arab Emirates ........ 1932 

Qom Basin, Iran ................................ 1956 

Oman Basin, Oman ............................. 1957 

Taurus-Zagros Foothill Belt, Turkey .............. 1961 

Ma'Rib-Al Jawf Basin, Yemen ................... 1984 

Shabwa, Yemen ................................. 1987 

Total ........................................................... 

Oil, 

cumulative 

recoverable 

discoveries 

through 1990, 

in barrels x 106 

225 

2,329 

913 

654 

910 

512 

553 

174 

44,023 

1,555 

330 

173 

240 

195 

706 

742 

840 

404 

1,345 

464 

138 

57,425 

133,132 

566,628 

175 

9,379 

620 

1,427 

500 

711,861 

Gas, 

cumulative 

recoverable 

discoveries 

through 1990, 

in cubic feet x 109 

15,093 

150,921 

440 

1,425 

80,268 

10,749 

144 

38 

108,354 

2,577 

140 

160 

2 

35 

8,925 

320 

650 

44,214 

7,734 

610 

2,685 

435,484 

576,982 

770,433 

1,138 

9,593 

281 

12,500 

0 

1,370,927 

30 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-communist Asia, and the SW. Pacific 
Table 4. Year of first discovery and cumulative recoverable oil and gas discoveries through 1990 in the 99 

significant petroleum provinces in the study area-Continued 

Petroleum province, country Year of first 

discovery 

Mrica (fig. 11) 

Gulf of Suez Basin, Egypt ..................... .. 

Pelagian Basin, Libya and Tunisia ............... . 

Niger Delta, Cameroon, Equatorial Guinea, 

and Nigeria .................................. . 

lllizi Basin, Algeria ........................... .. 

Hassi Messaoud High, Algeria .................. . 

Atchan Uplift, Algeria and Libya ................ . 

Gabon Coastal Basin, Gabon .................... . 

Lower Congo Basin, Angola, Congo, Gabon, 

1886 

1949 

1954 

1956 

1956 

1956 

1956 

and Zaire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1957 

Sirte Basin, Libya . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1958 

Ghadames Basin, Algeria, Libya, and Tunisia . . . . . 1958 

Oued Mya Basin, Algeria........................ 1961 

Muglad Basin, Sudan.. .. . .. .. .. .. . . .. .. .. .. .. .. . 1979 

Atchan Saddle, Libya............................ 1984 

Total .......................................................... . 

Non-Communist Asia (fig. 12) 

North Sumatra Basin, Indonesia.................. 1885 

East Java Basin, Indonesia . . . . . . . . . . . . . . . . . . . . . . . 1888 

Mizoram-Manipur Foothills, India . . . . . . . . . . . . . . . . 1889 

South Sumatra Basin, Indonesia.................. 1896 

Kutei Basin, Indonesia........................... 1897 

Tarakan Basin, Indonesia . . . . . . . . . . . . . . . . . . . . . . . . 1900 

Central Burma Basin, Myanmar . . . . . . . . . . . . . . . . . . 1902 

Baram Delta, Malaysia and Brunei................ 1910 

Potwar Basin, Pakistan .. .. . . .. .. .. . . . . . . .. .. .. .. 1915 

Central Sumatra Basin, Indonesia . . . . . . . . . . . . . . . . . 1920 

Salawati Basin, Indonesia........................ 1936 

Barito Basin, Indonesia .. .. . . .. .. .. . . . . . .. .. . .. .. 1937 

Tiga Pulah Arch, Indonesia...................... 1940 

Assam Basin, India.............................. 1953 

Cambay Basin, India .. . . . .. .. . . .. . . .. .. .. .. .. .. . 1958 

Narmada Graben, India.......................... 1960 

Balingian Basin, Malaysia . . . . . . . . . . . . . . . . . . . . . . . 1962 

Malaya Basin, Malaysia and Indonesia . . . . . . . . . . . . 1969 

West Java Basin, Indonesia . . . . . . . . . . . . . . . . . . . . . . 1969 

Sunda Basin, Indonesia.......................... 1970 

West Natuna Basin, Indonesia.................... 1972 

Bombay Basin, India............................ 1974 

Cauvery Basin, India............................ 1979 

Total .......................................................... . 

Southwestern Pacific 

Gippsland Basin, Australia . . . . . . . . . . . . . . . . . . . . . . . 1924 

North Carnarvon Basin, Australia................. 1953 

Papuan Fold Belt, Papua New Guinea............. 1956 

Bonaparte Basin, Australia....................... 1964 

Total .......................................................... . 

Oil, 

cumulative 

recoverable 

discoveries 

through 1990, 

in barrels x 106 

9,459 

2,237 

32,107 

2,532 

12,746 

1,553 

2,605 

6,790 

44,049 

2,447 

1,099 

499 

230 

118,353 

711 

386 

344 

2,915 

3,349 

447 

656 

6,074 

360 

13,399 

724 

180 

137 

1,585 

1,391 

637 

470 

4,697 

2,915 

1,141 

396 

4,494 

186 

47,594 

4,546 

695 

260 

375 

5,876 

1

The Pannonian Basin, which extends into Austria, is a significant province only in Eastern Europe. 

~e former Neutral Zone was located between Kuwait and Saudi Arabia. 

Gas, 

cumulative 

recoverable 

discoveries 

through 1990, 

in cubic feet x 109 

4,893 

5,685 

72,247 

27,226 

22,982 

5,271 

795 

7,971 

22,478 

7,526 

702 

0 

0 

177,776 

25,927 

7,697 

1,360 

5,386 

29,540 

1,502 

7,210 

25,562 

2,669 

2,060 

493 

66 

0 

1,785 

3,858 

528 

808 

18,487 

6,641 

639 

2,329 

16,278 

326 

161,151 

10,844 

2,773 

3,975 

6,779 

24,371 

Tables 1-6 31 
Table 5. Regional distribution of land area, delineated prospective area, explored area, and rate of addition to 

prospective area 

[Mexico is excluded from this table because drilling data are substantially incomplete. Data from figures 17-54. Some data in the last two columns are 

also shown in figures 14 and 15] 

Prospective Explored Rate of addition to Percentage of 

Region land area area through area through prospective area, total prospective 

(mi2 ) 1990 1990 1981-90 area delineated 

(mi2 ) (mi2) (mi2/wildcat well) by 1971 

Caribbean ................ 85,172 12,345 1,797 31.6 86.2 

Central America .......... 212,318 14,007 1,605 75.3 32.0 

South America ............ 6,863,319 430,794 105,895 33.7 46.2 

Western Europe ........... 2,224,255 479,186 106,340 24.5 55.4 

Middle East .............. 2,388,187 222,333 31,128 61.2 39.5 

Africa .................... 11,644,658 459,860 77,425 47.0 56.3 

Non-Communist Asia ..... 3,443,324 295,445 50,997 57.6 21.4 

Southwestern Pacific ...... 3,293,782 220,211 32,854 64.0 40.5 

Total ................ 30,155,015 2,134,181 408,041 42.3 45.9 

Table 6. Estimates of ultimate recovery of cumulative oil discovered by region from 

1900 to 1980 as recorded by Petroconsultants in the first tapes issued in 1981, 1984, 1987, 

and 1990 

[Oil in barrels X 106 • Data are graphed in figure 16] 

Region 

South America ............... . 

Western Europe .............. . 

Middle East .................. . 

Africa ....................... . 

Non-Communist Asia ......... . 

Total ................... . 

1981 

37,597 

27,270 

421,907 

72,216 

23,280 

582,270 

Petroconsultants' tape 

1984 

66,432 

31,069 

516,908 

78,510 

28,516 

721,435 

1987 

66,260 

31,899 

525,658 

86,829 

33,199 

743,845 

1990 

81,578 

35,847 

643,802 

84,471 

38,951 

884,649 

Percentage of 

oil discoveries in 

area delineated 

by 1971 

44.0 

88.2 

83.8 

30.2 

87.1 

89.7 

62.0 

79.4 

82.3 

32 Petroleum Exploration, Caribbean, Latin America, W. Europe, the Middle East, Africa, Non-Communist Asia, and the SW. Pacific 
FIGURES 1-16 

[An introduction to figures 17-54 and the figures themselves follow figure 16] 
w 

""" 11 

(/) 10 

c 

z 

<( 

(/) 9 ::::) 

0 

:J: 

1-

z 8 

en 

_J 

_J 

w 7 

~ 

(..) 

~ 6 

c 

_J 

~ 5 

u. 

0 

a: 

w 

c:c 4 ~ ::::) 

z 3 w 

> i= 

:3 2 

::::) 

~ ::::) 

(..) 1 

0 

1950 1960 1970 1980 1990 

YEAR 

Figure 1. Time profiles of the cumulative number of offshore and onshore wildcat wells drilled in South America, Western Europe, the Middle East, Africa, nonCommunist Asia, and the southwestern Pacific, 1950-90. Data are from a computer tape released in January 1991 by Petroconsultants S.A., Geneva, and are given 

by country and year in table 2. 
~ 

(,n 

w"" 

a: 

0 

:I: 

(/) 

u.. 

u.. 

0 

(/) 

-.I 

-.I 

w 

s !:i(/) 

uc 

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s=> 

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o:::I: 

a: I--

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r::c-

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::> 

z 

w 

> 

1--

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~ 

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(.,) 

3.4 

3.2 

3 

2.8 

2.6 

2.4 

2.2 

2 

1.8 

1.6 

1.4 

1.2 

1 

0.8 

0.6 

0.4 

0.2 

0 

1950 1960 1970 1980 

YEAR 

Western Europe 

South America 

Southwestern 

Pacific 

1990 

Figure 2. Time profiles of the cumulative number of offshore wildcat wells drilled in South America, Western Europe, the Middle East, Africa, non-Communist Asia, 

and the southwestern Pacific, 1950-90. Data are from a computer tape released in January 1991 by Petroconsultants S.A., Geneva. 
1500 ~------------------------------------~.---------------------, 40 

Cl) 

__J 

1350 

1200 

1050 

__J 900 w 

s !;:( 750 

u 

c 600 

__J 

s 450 

300 

150 

,..... 

0 

1968 

/ ......... _______ /·, 

/. Wildcat wells ~. _,.,. .......... 

1970 1972 1974 1976 1978 1980 

YEAR 

/" -- . . --- \ 

1982 1984 

\ 

·,,/·\ 

1986 1988 

36 

__J 

32 w a: 

a: 

28 <( aJ 

a: 

24 w a.. 

Cl) 

20 a: ::5 

16 c5 

c 

12 z 

w ... 

8 u 

a: 

a.. 

4 

0 

1990 

Figure 3. Time profile of annual wildcat drilling in the study area and U.S. refiners' crude-oil acquisition price, 1968-90. 

Wildcat well data are from a computer tape released in january 1991 by Petroconsultants S.A., Geneva, and crude-oil acquisition prices are from the American Petroleum Institute's Basic Petroleum Data Book, january 1992. Prices are in current dollars. 

36 

~ 30 w 

> 

a: 

w 

0.. 25 ~ 

X 

Cl) 

u:l 20 a: 

a: 

<( 

co 

~ 15 

ci 

w 

a: 

w 

~ 10 (..') 

Cl) 

i5 

g 5 

0 

1950 

A 

1960 1970 

YEAR 

EXPLANATION 

c:::JOffshore 

-Onshore 

1980 1990 
...... 

...... 

w 

60 

3: 50 

~ u 

c 

...... 

~ 40 0:: 

w 

a.. 

~ 

>< 30 Cl) 

...... 

w 

0:: 

0:: 

<( 

~ 20 

ci 

w 

0:: 

w 6 10 u 

Cl) 

iS 

...... 

0 0 

B 

-

-

-

-

1950 

150 

140 

0:: 130 <( 

w 

>- 120 0:: 

w 

a.. 110 N 

0 100 

>< 

1-

w 90 w 80 u.. 

u 

iii 70 :::::1 

u 

~ 60 

ci 

w 50 0:: 

w 40 > 

0 

u 

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<( 

(!) 10 

0 

1950 

I I I 

1960 

1960 

I 

1970 

YEAR 

1970 

YEAR 

I I I 

I 

I 

1980 

EXPLANATION 

CJOffshore 

-Onshore 

1980 

-

-

-

-

-

I 

1990 

1990 

~ Figure 4. Oil and gas discovery rates for the study area. A, Annual onshore and offshore oil discovery rates. B, Amount of oil discovered per wildcat well. C, Annual 

onshore and offshore gas discovery rates. For figure 4A-C, data are averaged for 5-

year periods, 1951-85, and the 4-year period, 1986-89. The estimates are from a 

computer tape released in january 1991 by Petroconsultants, and supplemental 

information on oil was provided by the Dallas Field Office of the Energy Information 

Administration. Oil or gas discovered was classified as offshore only when it was 

found in a field that was entirely offshore. 

37 
MIDDLE EAST 3 

SOUTH AMERICA 

22 2 

20 0 

6 

18 5 WESTERN EUROPE 

4 

a: 

16 a: 3 

<C <C w w > > 2 

a: a: w 14 w c.. c.. en en 0 0 

0 

X X 

Cl) 12 Cl) 

...J ...J w w 8 

a: a: 

a: a: 

<C <C 7 

al al 

z 10 z 6 

c:i" c"' w w 5 a: a: w w > 8 > 4 0 0 

u u 

Cl) Cl) 

c c 3 

...J 6 ...J 

0 0 2 

4 0 

3 

2 

2 

0 

1950 1960 1970 1980 1990 0 

YEAR 2 

EXPLANATION SOUTHWESTERN PACIFIC 

D Offshore 0 

-Onshore 

1950 1960 1970 1980 1990 

YEAR 

Figure 5. Annual offshore and onshore regional oil discovery rates for South America, Western Europe, the Middle East, Africa, 

non-Communist Asia, and the southwestern Pacific. Data are averaged for 5-year periods, 1951-85, and the 4-year period, 

1986-89. The field estimates of recoverable oil are from a computer tape released in January 1991 by Petroconsultants and 

were supplemented by information provided by the Dallas Field Office of the Energy Information Administration. Oil discovered was classified as offshore only when it was found in a field that was entirely offshore. 

38 
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1500 

1400 

500 

400 

300 

200 

100 

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1950 

MIDDLE EAST 

1960 1970 

YEAR 

1980 1990 

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20 

10 

0 

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30 

20 

10 

0 

AFRICA 

60 

50 

40 

30 

20 

10 

0 

NON-COMMUNIST ASIA 

30 

20 

10 

0 

SOUTHWESTERN PACIFIC 

10 • 0 

1950 1960 1970 1980 1990 

YEAR 

Figure 6. The amount of oil discovered per wildcat well for South America, Western Europe, the Middle East, Africa, nonCommunist Asia, and the southwestern Pacific. Data are averaged for 5-year periods, 1951-85, and the 4-year period, 

1986-89. The vertical scale of the graph for the Middle East is half the scale of the other graphs; even so, the discovery rate in 

the first period requires the graph to be broken. Wildcat-well data are from a computer tape released in january 1991 by 

Petroconsultants. The field estimates of recoverable oil are from a computer tape released in january 1991 by Petroconsultants 

and were supplemented by information provided by the Dallas Field Office of the Energy Information Administration. 

39 
a: 

<( 

w 

> 

a: 

w 

80 

70 

a.. 60 N 

0 

X 

1-

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w 

u.. 50 

(.,) 

a::l 

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c 

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C!J 

20 

10 

0 

1950 

MIDDLE EAST 

1960 1970 

YEAR 

1980 1990 

EXPLANATION 

D Offshore 

Onshore 

Figure 7. Annual offshore and onshore regional gas discovery 

rates for South America, Western Europe, the Middle East, 

Africa, non-Communist Asia, and the southwestern Pacific. 

Data are averaged for 5-year periods, 1951-85, and the 4-year 

period, 1986-89. The field estimates of recoverable gas are 

from a computer tape released in January 1991 by 

Petroconsultants. Gas discovered was classified as offshore 

only when it was found in a field that was entirely offshore. 

40 

a: 

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Figure 8. Frequency distribution of sizes of the 99 significant petroleum provinces identified through 1990 in the study area. Estimates of recoverable oil in each 

province are from a computer tape released in january 1991 by Petroconsultants, and supplemental information was provided by the Dallas Field Office of the Energy 

Information Administration. Each significant province has at least one field containing 100 million barrels of recoverable crude oil. All the significant provinces are 

named in table 4; the largest provinces are labeled in this graph . 
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1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 

YEAR OF FIRST DISCOVERY 

Figure 10. Historical sequence by year of the first discovery in each significant petroleum province of Western Europe. Heights of the spikes show the magnitude of 

total oil discovered through 1990 in each province. Discovery dates, discovery magnitudes, and province names are from a computer tape released in January 1991 by 

Petroconsultants and were supplemented by field estimates from the Dallas Field Office of the Energy Information Administration. Province discovery estimates are also 

given in table 4. 
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1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 

YEAR OF FIRST DISCOVERY 

Figure 11. Historical sequence by year of the first discovery in each significant petroleum province of Africa. Heights of the spikes show the magnitude of total oil discovered through 1990 in each province. Discovery dates, discovery magnitudes, and province names are from a computer tape released in january 1991 by 

Petroconsultants and were supplemented by field estimates from the Dallas Field Office of the Energy Information Administration. Province discovery estimates are also 

given in table 4. 
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1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 

YEAR OF FIRST DISCOVERY 

Figure 12. Historical sequence by year of the first discovery in each significant petroleum province of non-Communist Asia. Heights of the spikes show the magnitude 

of total oil discovered through 1990 in each province. Discovery dates, discovery magnitudes, and province names are from a computer tape released in january 1991 

by Petroconsultants and were supplemented by field estimates from the Dallas Field Office of the Energy Information Administration. Province discovery estimates are 

also given in table 4 . 
46 

YEAR 

1950 1960 

2.4 

1970 1980 1990 

2.2 A 

2 

1.8 

Delineated prospective area 

CC> 1.6 ~ 

X 

en 

w 1.4 ....I 

~ 1.2 w 

a: 

<( 

::::) 

Cl 

en 

~ 0.8 

<i. 

w 

a: 0.6 <( 

0.4 

0.2 

0 

0 10 20 30 40 

CUMULATIVE 1\JUMBER OF WILDCAT WELLS, IN THOUSANDS 

YEAR 

1950 1960 1970 1980 1990 

1.2 

1.1 

0.9 

N 

c 0.8 

X 

en 0.7 ....I 

w 

a: 

a: 

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~ 0.5 ...... 

0 0.4 

0.3 

0.2 

0.1 

0 

0 0.4 0.8 1.2 1.6 2 2.4 

DELINEATED PROSPECTIVE AREA, IN SQUARE MILES X 106 

Figure 13. Growth in delineated prospective area and explored area and growth in oil discovered in the 

study area. A, Growth in prospective and explored areas delineated by wells drilled through 1990 in the 

study area. B, Oil discovered through 1990 graphed by the year its field location was classified as part of 

the delineated prospective area in the study area. Well data are from a computer tape released in 

January 1991 by Petroconsultants. Calculation of delineated prospective and explored areas is explained 

in the text. Estimates of recoverable oil in each field are from a computer tape released in January 1991 

by Petroconsultants and were supplemented by information provided by the Dallas Field Office of the 

Energy Information Administration. 
YEAR YEAR 

1950 1960 1970 1980 1990 1950 1960 1970 1980 1990 500 600 

(I) SOUTH AMERICA w (I) 

w WESTERN EUROPE ....I ....I 500 ~ 400 ~ w w a: a: <( Delineated prospective area <( 

:::::1 :::::1 400 c:::l c:::l (I) 300 (I) 

u.. u.. 0 0 

(I) (I) 

0 0 300 z z <( 200 <( 

(I) (I) 

:::::1 :::::1 

0 0 200 :I: :I: ..... ..... 

~ ~ 

<i 100 w ~ 100 a: a: <( <( 

0 00 0 2 4 6 8 10 12 2 4 6 8 10 12 

CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS 

YEAR YEAR 

1960 1970 1980 1990 1960 1970 1980 1990 260 500 

240 (I) MIDDLE EAST (I) w AFRICA ....I 220 w 

~ ....I 

400 w 200 ~ a: w <( 180 a: :::::1 <( 

c:::l :::::1 

(I) 160 c:::l 

u.. (I) 300 0 140 u.. 

(I) 0 

0 (I) 

z 120 0 

<( z (I) <( 200 :::::1 (I) 

0 :::::1 

:I: 0 

..... :I: 

~ ..... 

~ <i <(. 100 w 

a: w <( a: 

20 <( 

00 0.4 0.8 1.2 1.6 2 2.4 2.8 00 2 4 6 

CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS 

YEAR YEAR 

350 

1960 1970 1980 1990 

260 1970 1980 1990 

240 (I) NON-COMMUNIST ASIA (I) 

w 300 w SOUTHWESTERN PACIFIC 220 ....I ....I 

~ ~ w w 200 a: 250 a: <( <( 180 :::::1 :::::1 c:::l Delineated prospective area c:::l Delineated prospective area (I) (I) 160 u.. 200 u.. 0 0 (I) (I) 140 0 0 z z 120 <( 150 <( (I) (I) 

:::::1 :::::1 100 0 0 :I: :I: ..... 100 ..... ~ ~ 60 

~ 50 a: a: 

~ 40 <( <( 

00 2 3 4 5 00 2 3 

CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS CUMULATIVE NUMBER OF WILDCAT WELLS, IN THOUSANDS 

Figure 14. Growth in prospective area and explored area delineated by wells drilled through 1990 for South America, Western 

Europe, the Middle East, Africa, non-Communist Asia, and the southwestern Pacific. The graphs are at different scales. Well 

data are from a computer tape released in january 1991 by Petroconsultants. Calculation of delineated prospective and 

explored areas is explained in the text. 

47 

8 

4 
YEAR 

1950 1960 

150 

1970 1980 1990 

140 

130 SOUTH AMERICA 

120 

110 

~ 100 

X 90 en 

...J 

w 80 a: 

a: 

<( 70 cc 60 ~ 

.J 50 

0 40 

30 

20 

10 

0 

0 200 400 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

YEAR 

800 .--1~96_o ________ 1_9r7o ____________ 1~98_o ______ 19~9_o __ ~ 

700 

~ 

600 

~ 500 ...J 

w 

a: 

~ 400 cc 

z 

::;. 300 

0 

200 

100 

MIDDLE EAST 

0 L-~--~~---~---L-~--~~---1---L-~--~~ 

~ 

X 

en 

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w 

a: 

a: 

<( 

cc 

~ 

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0 

0 40 80 120 160 200 240 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

1960 1970 

YEAR 

1980 1990 

60 .--.--~--------------.------------.----~ 

50 NON-COMMUNIST ASIA 

40 

30 

20 

10 

100 200 300 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

~ X 

en 

...J 

w 

a: 

a: 

<( 

cc 

~ 

....~-

0 

YEAR 

70 .-1~9~ _________ 1~96_0 _______ 1,9,70 _________ 1,98_0 _____ 1~99_,0 

60 

50 

40 

30 

20 

10 

0 

0 

WESTERN EUROPE 

200 400 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

1960 

YEAR 

1970 1980 1990 

150 .---~-----------------..---------.------,.---, 

140 

130 

120 

AFRICA 

'& 110 

x 100 en 

...J 

w 

a: 

a: 

<( 

cc 

~ 

....~-

0 

X 

~ w 

a: 

a: 

<( 

cc 

~ 

....~-

0 

90 

80 

70 

60 

50 

40 

30 

20 

10 

0 

6 

5 

4 

3 

0 200 400 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

1960 1970 

YEAR 

1980 1990 

0 ~~==L-~--~~~~--L-~--~~~~--~~ 

0 40 80 120 160 200 240 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Figure 15. Oil discovered through 1990 graphed by the year its field location was classified as part of the delineated prospective area for South America, Western Europe, the Middle East, Africa, non-Communist Asia, and the southwestern Pacific. The 

graphs are at different scales. Calculation of delineated prospective area is explained in the text. Estimates of recoverable oil in 

each field are from a computer tape released in january 1991 by Petroconsultants and were supplemented by information provided by the Dallas Field Office of the Energy Information Administration. 

48 
1000 

900 A en 800 ~ 

X 

Cl) 700 ...J 

w 

a: 

a: 

<( 600 al 

z 

::~ 500 

0 

w 

> 400 i= 

:5 

=> 300 ~ 

=> 

(..) 

200 

100 

0 

1901 1911 

300 

270 

B 

240 en 

~ 

X 210 Cl) 

...J 

w 

a: 

a: 180 <( 

al 

~ 150 ...J~ 

0 

w 120 > 

~ 90 => 

~ 

=> 

(..) 60 

30 

0 

1901 1911 

EXPLANATION 

1990 data 

-- 1987data 

- - - - 1984 data 

· · · · · · · · 1981 data 

1921 1931 

EXPLANATION 

--- 1990data 

-- 1987data 

---- 1984data 

· · · · · · · · 1981 data 

1921 1931 

1941 1951 

YEAR OF DISCOVERY 

1941 1951 

YEAR OF DISCOVERY 

_/- 7 

~/ 

- .... 

1961 1971 1981 

Field growth 

1961 1971 1981 

Figure 16. Growth in fields discovered by 1980 in five regions. A, Cumulative amounts of oil discovered in South America, Western Europe, the Middle East, Africa, and non-Communist Asia calculated 

from field estimates of ultimate recovery as recorded in field tapes received from Petroconsultants at 

3-year intervals in 1981, 1984, 1987, and 1990. The difference between the 1981 and 1984 curves is 

primarily due to late reporting of earlier discoveries. Actual field growth is approximated by the difference between the 1984 and 1990 curves. 8, Data on the same regions as in figure 16A, except 

data for the Middle East are excluded. 

49 

FIGURES 17-54 

Figures 17-54 show the delineated prospective areas, explored areas, and known petroleum 

provinces of the Caribbean, Latin America, Western Europe, the Middle East, Africa, non-Communist 

Asia, and the southwestern Pacific. No figure was prepared for Mexico because data were incomplete. 

Each figure contains a map, two graphs (except figures 36, 42, and 46, which have only one graph each 

because oil field sizes are not available), and a summary of exploration data. If significant petroleum 

provinces are present in the mapped area, a table provides information on them. Definitions of terms and 

sources of information in figures 17-54 are given below. 

Maps.-All maps were drawn by ARC/INFO software ( 1987, Environmental Systems Research 

Institute, Redlands, Calif.); country boundaries are from the World Data Bank II released by the U.S. 

Central Intelligence Agency and are not necessarily correct. Scales are not provided as the scale varies 

within many of the maps. The methods for computing and identifying the delineated prospective and 

explored areas are explained in the text and differ from those used in U.S. Geological Survey (USGS) 

Circular 981. If only part of a country is shown, no explored or delineated prospective area was identified 

in the rest of the country. The grid point closest to a well drilled inside the country mapped may plot as 

an isolated circle outside the border of that country. 

Names of known petroleum provinces (called basins on some maps) and years of first discoveries in 

them in each country are shown on each map and are from a computer tape released in January 1991 by 

Petroconsultants S.A., Geneva. Of all the known petroleum provinces shown in figures 17-54, 99 have 

at least one field containing 100 million barrels and were therefore classified as significant (see table 4). 

Information on the significant provinces is given in the tables facing the maps. 

Graphs.-The graphs show (1) the growth in delineated prospective area and explored area in 

relation to the cumulative number of wildcat wells drilled in a country or group of countries through 1990 

and (2) the profile of discovered oil cumulated through 1990 ordered by when its field location was 

classified as part of the delineated prospective area. Years are shown at the top of both graphs. Wildcat 

wells are from a computer tape released in January 1991 by Petroconsultants. The well data graphed are 

those in table 2 minus the wells whose dates or coordinates are unknown; some wells are assigned to a 

country in table 2 but lack coordinates and cannot be used to delineate prospective area. Estimates of 

recoverable oil and gas in each province are from a computer tape released in January 1991 by 

Petroconsultants and from supplemental information provided by the Dallas Field Office of the Energy 

Information Administration of the U.S. Department of Energy (written commun., 1990). 

Many wildcat wells drilled before 1950 were not recorded in our data so that the delineated 

prospective and explored areas as of 1950 are underestimated. Records of followup drilling after 1950 

probably result in an overestimate of the rate of increase in the delineated prospective area after 1950. 

Nonetheless, we believe that the growth in delineated prospective area after 1970 is real and is not an 

artifact of earlier missing data. Rate of growth in explored area has been relatively constant since 1950. 

Summaries of exploration data.-Land areas are from individual country entries in The Random 

House College Dictionary (Random House, Inc., 1973). Computation of the delineated prospective areas 

and the explored areas is explained in the text. Wildcat wells are from a computer tape released in January 

1991 by Petroconsultants; the 1990 totals are those in table 2 minus the wells whose dates or coordinates 

are unknown. Current growth in delineated prospective area per wildcat well is derived from the graph 

showing growth in prospective area. Reported discoveries of recoverable crude oil and gas are from a 

Petroconsultants computer tape released in January 1991 and from the Dallas Field Office of the Energy 

Information Administration of the U.S. Department of Energy (written commun., 1990). The information 

on discoveries is incomplete. 

For consistency with USGS Circular 981, the oil richness indices have been calculated and presented 

in figures 17-54. This index is defined as the number of barrels of recoverable crude oil discovered 

through 1990 divided by the number of square miles in the delineated prospective area. The factor tends 

to be largest in areas such as the Middle East where exploration has been concentrated in a few very prolific 

areas. As shown by the accompanying graphs, most oil is concentrated in a small part of the prospective 

area, and the total resources of a country should not be estimated by multiplying the richness by a higher 

figure for the prospective area. 

Tables of significant· provinces. -The tables contain provinces that are significant in the country 

mapped and provinces that are significant in neighboring countries but that have not had discoveries of 100 

million barrels of oil in the country mapped. Some of the extensions of significant provinces contain only 

natural gas and natural gas liquids. 
"' "' 

30 N 

25 N 

20 N j 

15 N + ....:. 

r-\ 10 N 

85 w 

1956 Las Villas 

Zone 

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• 

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t 

A ~ 

q \ ~~ 

1881 Almendares 

San Juan Zone 

II 'f~ 

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............. ..._ ........ 

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r I J( 

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cw:> • .(<P~ 

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• "'1896 Northeast 

Caribbean 

Deformed Belt 

, 

\ ~ 

- \._ fo c=> 1l 

70 w 65 w 60 w 

Figure 17. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of the Caribbean. 

55 w 
Ill 

"' 

Growth in prospective and explored areas through 1990 

14 1950 1960 1970 1980 1990 

13 

~ 12 

~ 11 w 

~ 10 

a 9 en 

u.. 

a 

en 

Cl 

::::> 

~ a 

i= 4 z 

- _ 3 

;:;5 

a: 

<( 

Delineated prospective area 

40 80 120 160 200 240 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

150 1950 1960 1970 1980 1990 

140 

130 

120 

~ 110t-

~ 100 

,-------

X 

~ 90 w 

a: 80 a: 

<( 70 "' 

~ 60 __ ; 50 0 

40 

30 

20L 10 

0 

0 2 4 6 8 10 12 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Country 

Bahamas . ... .... . .. ... ..... . . .. ....... .. .. .. . .... .. . 

Cuba' . ...... . ....... .... . . .. . . .... .. . ........ . . .. . . . 

Haiti .. ... ............ .. .. . ...... .. ......... . . .... .. . 

Dominican Republic . .. ... .... .. . .. . . . ... . . .. ....... . . . 

Jamaica .. . ...... . .. . .. .. ........ ... ... .... .. •. .... .. 

Barbados .......................... ....... . .... . . .. . . 

Lesser Antilles 2 .• • ••.. •••• • • •• ••• • . • • •• •••••• • • ••••••• 

Land area 

(mi2) 

4,404 

44,218 

10,714 

19,129 

4,413 

161 

2,133 

Total . . . . .. .. ......... • ... ... ..... ......... ... .. . . 85,172 

1 Data for Cuba are incomplete since 1960. 

Delineated prospective area through 1990: 12,345 mi 2 

Explored area through 1990: I ,797 mi2 

Wildcat wells through 1990: 223 

Current growth in delineated prospective area per wildcat: 141 mi 2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0. 109 X 109 bbl oil and 0. 166 X 1012 cubic feet gas 

Richness= total oil discoveries 0 _

008 x 106 bbUmi2 

total delineated prospective area 

2For this report, the Lesser Antilles are considered to consist of tbe islands from Grenada to St. Thomas, except Barbados, which is listed separately. 

Figure 17. Continued. 
25 N 

\ 

20 N 

• • • • • 

• • 

15 N I 

• 

10 N 

COSTA RICA 

5 N 

95 w 90 w 85 w 80 w 75 w 

Figure 18. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Central 

America. 

54 
Growth in prospective and explored areas through 1990 

1955 1960 1970 1980 1990 

15r---.-----,------,---------,-------,---, 

14 

~ 13 

~ 12 u.J 

~ 11 

a 10 

~ 9 0 

"' 0 

z 

<( 

"' ::::> 

0 

~ 

~ 

~ cc 

<( 

Delineated prospective area 

Explored area 

40 80 120 160 200 240 

CUMULATIVE NUMBER OFWILDCATWELLS 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

100 

90 

80 

:g 70 

X 

~ 60 u.J 

cc 

~ 50 

"' 

~ 40 .J 

0 30 

20 

10 

1955 1960 1970 1980 1990 

0 0 2 4 6 8 10 12 14 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Country 

Belize ............... . ....... .. .. .. . . .............. . 

Honduras ........................... . ............... . 

Guatemala . .... ... . ... . ............................. . 

Nicaragua .....• ... ..•..... .. ............. . ..... . .. .. 

El Salvador ... . . ... ... ..... . . ....................... . 

Costa Rica ...... ... ... ....... ....................... . 

Panama . ....... . .... . ..... ......................... . 

8,867 

43 ,277 

42,042 

57,143 

13,176 

19,238 

28,575 

Total . .... .............................. .. . ....... 212,318 

Figure 18. Continued. 

Delineated prospective area through 1990: 14,007 mi2 

Explored area through 1990: I ,605 mi2 

Wildcat wells through 1990: 229 

Current growth in delineated prospective area per wildcat: 87 mi2 

Reported discoveries of recoverable crude oil through 1990: 

0.068 X 109 bbl 

Richness total oil discoveries 0.005 x 106 bbVmi2 

total delineated prospective area 

55 
9 N 

• • • 

7 N 

• • • 

• 

' 

GUYANA 

5 N 

SURINAME 

3 N 

1 N 

BO W 55 w 50 w 

Figure 19. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Guyana, 

Suriname, and French Guiana, South America. French Guiana is listed separately although it is an overseas department of France. 

56 
Growth in prospective and explored areas through 1990 

1966 1970 1980 1990 

(/) 2.8 

~ 2.6 ~ 2.4 w Delineated prospective area 0: 

<( 2.2 :::;) 

c:l 

(/) 

u.. 1.8 a 

(/) 1.6 0 

z 

<( 1.4 (/) 

1.2 :::;) 

a 

:I: 1 >--

;;;:: 0.8 <(-

w 0.6 0: 

<( 0.4 Explored area 

0.2 

0 

0 20 40 60 

CUMULATIVE NUMBER OF WILDCAT WELLS 

8 

X 

:3 

w 

0: 

0: 

<( 

ID 

;;;:: 

_j 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1966 1970 1980 1990 

100 

90 

80 

70 

60 

50 I 

40 

30 

20 

10 

oU-~-L~--L-~~~--~-L~--L-~-L~~ 

0 0.4 0.8 1.2 1.6 2 2.4 2.8 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Country 

Guyana . . . . . . . . . . . . . . . . . . . . . . . • . . . . . • . . . . . . . . . . • . . . . 82,978 

Suriname. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60,230 

French Guiana . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 ,135 

Total ............ .. ...... . .. . ................... .. 178,343 

Figure 19. Continued. 

Delineated prospective area through 1990: 2,568 mi2 

Explored area through 1990: 479 mi2 

Wildcat wells through 1990: 54 

Current growth in delineated prospective area per wildcat: 6 mi2 

Reported discoveries of recoverable crude oil through 1990: 

0.054 X 109 bbl 

Richness total oil discoveries 0.019 x 106 bbUmi2 

total delineated prospective area 

57 
58 

15 s 

20 s 

25 s 

30 s 

35 s 

40 s 

45 s 

50 s 

55 s 

60 s 

1968 Arauco 

Basin 

1972 Valdivia 

Basin 

80 w 75 w 70 w 65 w 

Figure 20. Delineated prospective areas (gray circles), explored 

areas (black circles), and known petroleum provinces of Chile, 

South America. 
Growth in prospective and explored areas through 1990 

14 1950 1960 1970 1980 1990 

en 

~ 12 

:E 

w 

~ 10 

a 

en 

u.. 

0 

en 

c 

z 

<( 

en 

::::> 

0 

:I: 

1-

~ 

::1io::: 

<( 

200 400 

CUMULATIVE NUMBER OFWILDCATWELLS 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

700 

600 

§ 500 

X 

a400 

0::: 

0::: 

<( 

~ 300 

_; 

5 200 

TOO 

1950 1960 1970 1980 1990 

2 4 6 8 10 12 14 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Land area: 286,396 mi2 

Delineated prospective area through 1990: 12,985 mi2 

Explored area through 1990: 3,762 mi2 

Wildcat wells through 1990: 484 

Figure 20. Continued. 

Current growth in delineated prospective area per wildcat: 5 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.602 x 109 bbl oil and 9.79 x 1012 cubic feet gas 

Richness to~ oil discoveri~s 0.046 x 106 bbllmi2 

total delineated prospective area 

59 
60 

15 s 

20 s 

25 s 

30 s 

35 s 

40 s 

45 s 

50 s 

55 s 

60 s 

80 w 

1933 

Michicoia-Boqueron 

Arch 

1937 Cretaceous Basin 

1932 Cuyo Basin 

1922 Neuquen 

Basin 

1949 Austral Basin 

70 w 

1928 Sub-Andean Zone 

PARAGUAY 

• • 

• • • 

• • 

• • • 

• • 

•• 

ARGENTINA 

• 

• 

• 

1916 San Jorge Basin 

...... ,. 1961 Malvinas 

~ 

Basin 

• c 

60 w 50 w 

Figure 21. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of 

Argentina, Uruguay, and Paraguay, South America. 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 1960 1970 1980 1990 1950 1960 1970 1980 1990 

120 

"' 110 

~ 100 ::;: 

w 90 "' ct 

::::> 

d 80 

"' u.. 70 0 

"' 0 60 z 

ct 50 "' ::::> 

0 

:I: 40 I-

~ 30 ct' 

w 20 "' ct 

10 

Delineated prospective area 

X 

~ 

"' "' ct 

"' 

~ 

_; 

0 

QL--L--~~--~--L--L--~~--~~~~~ 

1000 2000 3000 4000 0 20 40 60 80 100 120 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

San Jorge Basin . ..... . , . .. .... .. ....... , ..... . . 

Neuquen Basin . ... .. . , . .. . ... . . , ..... . , ..... , . 

Sub-Andean Zone .... . .. ......... . ..... . ...... . 

Cuyo Basin .......... . ...... .. .. .. ... . ....... . 

Austral Basin ..... .. .. , . .. . . . .......... , .. . ... . 

Year of first 

discovery in 

this province 

in Argentina 

1916 

1922 

1928 

1932 

1949 

Total. ...... , ... ,, . ... . , , .... , ........... . ............... , . . 

Exploration data 

Cumulative discoveries in this 

province in Argentina through 1990 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

2,517 

1,209 

110 

1,056 

100 

4,992 

in all 

fields 

(106 bbl) 

3,893 

2,668 

142 

1,484 

759 

8,946 

Gas 

in all 

fields 

(109 fel 

6,491 

25,895 

348 

356 

12,676 

45,766 

Land area 

(mi 2

) 

Delineated prospective area through 1990: 113,354 mi2 

Country 

Argentina .................... , . .. . . , ..... , .... , ... . 

Uruguay ......... .. .......... . ..... .. ............. . 

Paraguay .... .. ...... . ... .. ... ......... . ..... ... ... . 

1,084,120 

72,172 

157,047 

Total .. . ............ . ... . .... .. . ...... . .... .... . . 1,313,339 

Figure 21. Continued. 

Explored area through 1990: 30,303 mi2 

Wildcat wells through 1990: 3,179 

Current growth in delineated prospective area per wildcat: 33 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

8.13 x 109 bbl oil and 49.4 x 1012 cubic feet gas 

Richness 

total oil discoveries 

total delineated prospective area 0.072 X 106 bbl!mi2 

61 
3 N 

0 

3 s 

6 s 

1918 Progreso 

Basin 

83 w 

1980 Napo 

High 

ECUADOR 

78 w 

1972 Pastaza 

Basin 

73 w 

Figure 22. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Ecuador, South 

America. 

62 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

20 

1950 1960 1970 1980 1990 

"' 18 ~ 

~ 16 w 

a: 

<( 14 ::;, 

Cl 

"' u.. 12 Delineated prospective area 

0 

"' C> 10 z 

<( 

"' ::;, 

0 

:r 

.... 

~ 

<i 

w 

a: 

<( 

CUMULATIVE NUMBER OF WILDCAT WELLS 

240 

4.5 ,--....:1.:;95:.:.0....:1.;..:960:.:___:.19:;.7.:..0 ________ 1.,98:.:0 __ __:1.,990:..::..._-----, 

3.5 

8 

~ 3 

~ 

~ 2.5 a: 

<( 

ID 

~ __ ; 

0 1.5 

0.5 

oCL~~~~~~~~~~~~ 

0 2 4 6 8 10 12 14 16 18 20 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Progreso Basin .... ... . . .... . ........ . ..... . ... . 

Napo Basin ................... . .............. . 

Year of first 

discovery in 

this province 

in Ecuador 

1918 

1967 

Cumulative discoveries in this 

province in Ecuador through I 990 

Crude oil 

in 100-rnillionbarrel fields 

(106 bbl) 

130 

2,853 

in all 

fields 

(106 bbl) 

145 

3,748 

Gas 

in all 

fields 

oo• fel 

464 

659 

Total. .......................... .. .... . .... .... . .. ...... ... . 2,983 3,893 1,123 

Land area: 104,510 rni2 

Delineated prospective area through 1990: 17,715 mi2 

Explored area through 1990: 3,015 rni2 

Wildcat wells through 1990: 216 

Figure 22. Continued. 

Exploration data 

Current growth in delineated prospective area per wildcat: 125 rni2 

Reported discoveries of recoverable crude oil and gas through 1990: 

4.0 x 109 bbl oil and 1.12 x 1012 cubic feet gas 

Richness total oil discoveries 0.226 x 106 bbllrni2 

total delineated prospective area 

63 
15 N 

1976 Upper Guajira 

Basin 

1913 Sinu Basin 

10 N 

5 N 

0 

5 s 

1943 San Jorge 

Basin 

1950 Upper 

Magdalena 

Basin 

80 w 75 w 

• 

1976 Yari 

Basin 

1973 Lower 

Guajira Basin 

1920 Catalumbo Basin 

Basin 

70 w 65 w 

Figure 23. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Colombia, 

South America. 

64 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 

80 

(/) 

~ 70 

~ 

w 

a: 60 ..: 

::::J 

d 

(/) 50 "-CJ 

(/) 

CJ 40 z 

..: 

(/) 

::::J 

CJ 30 :I: 

1-

~ 20 ..:' 

w 

1960 1970 1980 

Delineated prospective area 

1990 

X 

~ w 

a: 

a: 

..: 

ID 

z 

::J 3 

0 

1950 1960 1970 1980 1990 

a: 

..: 10 Explored~ar~e~a ~-------

0 0~--~----~--~~--~----~---J-----L--~ 

0 200 400 600 800 1000 1200 o m ~ w oo 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Middle Magdalena Basin ...... .. .. . ..... . . . . . . . . 

Catatumbo Basin ......................... . .... . 

Llanos Basin .................•................ 

Putumayo Basin .................. . ....... .. ... . 

Upper Magdalena Basin . ..... .... . .. , ..... , .... . 

Ariari-Apiay Block .. . ..... ... .... . , .... .. , . ... . 

Barinas-Apure Basin ..... . ... ...... ... .. .. . . ... . 

Year of first 

discovery in 

this province 

in Colombia 

1918 

1920 

1948 

1949 

1950 

1969 

1980 

Cumulative discoveries in this 

province in Colombia through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

{106 bbl) {106 bbl) 

1,902 2,379 

400 473 

2,050 2,413 

242 370 

534 968 

100 255 

0 9 

Gas 

in all 

fields 

(109 fe) 

3,097 

922 

71 

1,261 

243 

221 

10 

Total ..............•. .... •..... . ..........•................. 5,228 6,867 5,825 

Land area: 439,828 mi2 

Delineated prospective area through 1990: 74,725 mi2 

Explored area through 1990: 12,852 mi2 

Wildcat wells through 1990: I ,260 

Figure 23. Continued. 

Exploration data 

Current growth in delineated prospective area per wildcat: 64 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

6.99 x 109 bbl oil and 11.4 x 1012 cubic feet gas 

Richness total oil discoveries 0.094 X 106 bbl/mi2 

total delineated prospective area 

65 
0 

5 s 

1975 Nuto High 

lOS 

15 s 

20 s 

85 w 

• 

80 w 75 w 

• 

.. 1984 Sub-Andean Zone 

• 

70 w 65 w 

Figure 24. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Peru, South 

America. 

66 
Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 

15r-.-------,-----,----------.------r----. 

14 

"' 

~ 13 

:E 12 w 

~ 11 

2l 10 

"' u.. 

c:::> 

"' c:::> 

z 

<( 

"' ::::> 

c:::> 

:I: 

>--

~ 4 

;:;5 3 a: 

<( 

Delineated prospective area 

100 200 300 400 

~ 

X 

~ w 

a: 

a: 

<( 

CD 

~ 

...i 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 1960 1970 1980 

4 

3.5 

2.5 

1.5 

1990 

CUMULATIVE NUMBER DFWILDCATWELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Progeso Basin .............. .. .. ........ .. .... . 

Talara Basin ................................. . . 

Maranon Basin ......... . ............ ....... . . . 

Sub-Andean Zone ............. . ....•........... 

Year of first 

discovery in 

this province 

in Peru 

1863 

1875 

1971 

1984 

Cumulative discoveries in this 

province in Peru through 1990 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

0 

2,226 

564 

0 

in all 

fields 

(106 bbl) 

7 

2,442 

1,163 

0 

Gas 

in all 

fields 

(109 fe) 

40 

2,629 

78 

16,000 

Total ...................................................... . 2,790 3,612 18,747 

Land area: 496,222 mi2 

Delineated prospective area through 1990: 14,259 mi2 

Explored area through 1990: 2,948 mi2 

Wildcat wells through 1990: 344 

Figure 24. Continued. 

Exploration data 

Current growth in delineated prospective area per wildcat: 138 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

3.67 x 109 bbl oil and 19.7 x 1012 cubic feet gas 

Richness total oil discoveries 0.257 x 106 bbllmi2 

total delineated prospective area 

67 
a-

= 

12 N 

8 N 

4 N 

0 

75 w 

VENEZUELA BASINS 

1 1979 Carupano Trough 

2 1980 Paria - West Tobago Basin 

TRINIDAD AND TOBAGO BASINS 

3 1975 Paria - West Tobago Basin 

4 1912 Southern Range Uplift 

5 1867 Eastern Venezuela Basin 

6 1911 Naparima Thrust Belt 

1980 Cariaco Trough 

VENEZUELA 

70 w 65 w 60 w 

Figure 25. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Venezuela and Trinidad and Tobago, 

South America. 
Growth in prospective and explored areas through 1990 

1930 1940 1950 1960 1970 1980 1990 90 

"' 80 ~ 

~ w 70 cr: 

<{ 

::> 

d 60 

"' u. 

0 50 "' c 

z 

<{ 40 

"' :;;, 

0 

:I: 30 1-

~ 

...:' 20 w 

cr: 

<{ 10 

0 

0 

Country 

Delineated prospective area 

400 800 1200 1600 2000 2400 

CUMULATIVE NUMBER OFWILDCATWELLS 

Exploration data 

Land area (mi2) 

Delineated prospective area through 1990: 

85,636 mi 2 

Explored area through 1990: 28,884 mi 2 

Venezuela . . . . . . . . . . . . . . . 352,143 

Trinidad and Tobago....... 1,980 Wildcat wells through 1990: 2,421 

Total.. . ... ..... . ... . . . 354,123 

~ Figure 25. Continued. 

Current growth in delineated prospective area per 

wildcat: 72 mi 2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 97 .7 x 109 bbl oil and 

63.2 x 1012 cubic feet gas 

total oil discoveries 

Richness total delineated prospective area 

= 1.139 x 106 bbl/mi 2 

m 

0 

X 

~ cr: 

cr: 

<{ 

al 

~ 

J 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

120 1930 1940 1950 1960 1970 1980 1990 

110 

100 

90 

80 

70 

60 

50 

40 

30 

20 

10 

0 

0 w w ~ ~ 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

in this country 

Cumulative discoveries in this 

province in this country through 1990 

Significant petroleum 

province 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

Venezuela 

Eastern Venezuela Basin.. .. 1901 

Maracaibo Basin . . . . . . . . . . 1914 

Falcon Basin . . . . . . . . . . . . . 1921 

Serrania Interior Oriental Belt 1928 

Greater Furrial Trend . . . . . . 1929 

Barinas-Apure Basin . . . . . . . 1948 

Total . . . .. .. . . ... .. ................... . 

17,940 

58,879 

100 

810 

9,064 

1,513 

88,306 

Trinidad and Tobago 

Eastern Venezuela Basin.... 1867 

Southern Range Uplift . . . . . 1912 

Total . . . ......... . .. ... . . . . · · · · · · · · · · · · 

2,579 

255 

2,834 

in all 

fields 

(106 bbl) 

21,737 

59,667 

371 

922 

9,253 

1,662 

93 ,612 

3,691 

288 

3,979 

Gas 

in all 

fields 

(109 ft3

) 

11,131 

17,370 

395 

2,358 

6,918 

3 

38,175 

14,780 

356 

15,136 
" Q 

8 s 

12 s 

• 

16 s 

• 

• 

20 s 

24 s 

75 w 70 w 

• 

• 

• 

• • 

•• 

BOLIVIA 

65 w 60 w 

Figure 26. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Bolivia, South America. 

55 w 
Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 24 

"' 22 

~ 20 ~ w 

a: 18 < ::;:) 16 Cl 

"' u.. 14 0 

"' 0 12 z 

< 10 "' ::;:) 

0 

:X: 

>--

~ 

..:· 

w , I / Explored area a: 

< 2 

0 

0 40 80 120 160 200 240 280 

CUMULATIVE NUMBER OFWILDCATWELLS 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 1960 1970 1980 1990 

600 

500 

§ 400 X 

~ w 

~ 300 <D 

~ 

d 200 0 

100 

0 

0 2 4 6 8 10 12 14 16 18 20 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data Significant petroleum province 

Land area: 404,388 mi 2 

Delineated prospective area through 1990: 

20,937 mi 2 

Explored area through 1990: 3,252 mi2 

Wildcat wells through 1990: 265 

Current growth in delineated grospective 

area per wildcat: 98 mi 

:::! Figure 26. Continued. 

Reported discoveries of recoverable crude oil 

and gas through 1990: 0.498 X 109 bbl 

oil and 6.33 x 10 12 cubic feet gas 

total oil discoveries 

Richness . . total dehneated prospecttve area 

=0.024 X 106 bbUmi2 

Significant petroleum 

province 

Sub-Andean Zone ........ . 

Year of first 

discovery in 

this province 

in Bolivia 

1926 

Cumulative discoveries in this 

province in Bolivia through 1990 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

0 

in all 

fields 

(106 bbl) 

147 

Gas 

in all 

fields 

(109 ft3) 

305 
10 N 

5 N 

0 

5 s 

10 s 

BRAZIL 

15 s 

• 

• • 

20 s 

• • • 

• • • 

25 s 

30 s 

35 s 

75 w 70 w 65 w 60 w 55 w 

• • • • • • • • . ., • • - • 

• 

• 

• •• . ., 

.. 

50 w 

.. • 1939 Reconcavo Basin 

• • 

• 

• 

• 

1975 Campos Basin 

45 w 40 w 

1957 

SergipeAlagoas 

Basin 

• 

35 w 30 w 

Figure 27. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Brazil, South 

America. 

72 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 

100 

1980 1990 14 .-~19~6~0 ____ ~19T7~0 ____________ ~19~B~0 ________ ~1~99=0---, 

en 90 ~ ::;;; 

w 80 a: 

<( 

::> 70 0 

en 

u. 

0 60 en 

Cl 

2 50 <( 

en 

::> 40 Cl 

:I: 

1- 30 !': 

<(-

w 20 a: 

<( 

10 

Delineated prospective area ~ 

X 

~ w 

a: 

a: 

<( 

"' !': 

__ ; 

0 

12 

10 

400 BOO 1200 1600 2000 2400 20 40 60 80 100 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Reconcavo Basin ... . ......... .. .... .. .... . .... . 

Sergipe-Aiagoas Basin . ... .... . . ... . .. . . . . ... .. . 

Potiguar Basin ......... .. . ... . .... . . . . . . . . ... . . 

Campos Bas in . . . . . .. . . .. .. . . .. ........... .. .. . 

Santos Basin ..... . .... . ..... • ..... . .. . .. . ..... 

Year of first 

discovery in 

this province 

in Brazil 

1939 

1957 

1973 

1975 

1979 

Cumulative discoveries in this 

province in Brazil through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

1,285 1,608 

330 736 

227 428 

9,244 10,005 

120 120 

Gas 

in all 

fields 

(109 ft') 

2,001 

1,379 

747 

11,654 

333 

Total. ....... .. .... . ..... . .... . ............... . ... . . . ... .. . . 11,206 12,897 16,114 

Land area: 3,286,170 mi2 

Delineated prospective area through 1990: 88,615 mi2 

Explored area through 1990: 20,400 m? 

Wildcat wells through 1990: 2,407 

Figure 27. Continued. 

Exploration data 

Current growth in delineated prospective area per wildcat: 23 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

13.28 x 109 bbl oil and 19.1 x 1012 cubic feet gas 

Richness total oil discoveries 0_

149 x 106 bbUmi 2 

total delineated prospective area 

73 
" ... 

70 N t 

65 N t 

60 N t 

55 N + 

IB-1 

,. 

DENMARK 

NETHERLANDS 

GERMANY 

50 N t 

45 N t UIC-1----,.-

40 N t ~ 

20W t nu-1 ~~ t l ":!:=' ~ 

15 w t -~ -~ ANDOR:;O ~ ~ t 30 E 

lOW t t t t 25E 

5W t t 20E 

O 5 E 10 E 15 E 

Figure 28. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of the northern part of Western 

Europe. 
80 N 

75 N 

10 E 

;:;: Figure 28. Continued. 

Area north of mainland Norway EXPLANATION OF PROVINCE DESIGNATIONS 

SVALBARD 

/ 

.;::; 

• 

+ 30 E 

20 E 

DENMARK SWEDEN 

DEN -I 1966 North Sea Graben 

-2 1980 Northwest German Basin 

FRANCE 

FRA -I 1967 North Pyrenean-North 

Cantabrian Zone 

-2 1939 Aquitaine Basin 

-3 1924 Languedoc-Provence Basin 

-4 1951 Golfe Du Lion-Camargue 

Basin 

-5 1957 Jura Fold Belt 

-6 1954 Anglo-Paris Basin 

-7 1952 Upper Rhine Graben 

IRELAND 

IRE -I 1978 Porcupine Basin 

-2 1971 Celtic Sea Graben 

NETHERLANDS 

NETH -I 1943 Northwest German Basin 

-2 1949 Anglo-Dutch Basin 

-3 1968 North Sea Graben 

NORWAY 

NOR -I 1987 More Basin 

-2 1968 Vestland Arch 

-3 1969 North Sea Graben 

-4 1979 Horda Platform 

-5 1972 Norwegian-Danish Basin 

-6 1985 Voring Basin 

-7 1981 Kristiansund-Bodo Fault 

Complex 

-8 1984 Trondelag Platform 

-9 1981 South Barents Sea Basin 

-10 1977 Vestspitsbergen Trough 

(small map) 

SWE -1 1987 Fennoscandian Shield 

-2 1968 Baltic Depression 

UNITED KINGDOM 

UK -1 1895 Anglo-Paris Basin 

-2 1938 Welsh Platform 

-3 1918 Pennine High 

-4 1939 East Irish Sea Basin 

-5 1939 Anglo-Dutch Basin 

-6 1938 Midland Valley Graben 

-7 1977 West Shetland Basin 

-8 1984 Faroes-Shetland Trough 

-9 1969 North Sea Graben 

-10 1975 East Shetland Platform 

-II 1972 Vestland Arch 

-12 1971 Mid North Sea High 

GERMANY 

G -1 1883 Molasse Basin 

-2 1935 Upper Rhine Graben 

-3 1874 Northwest German Basin 

-4 1974 North Sea Graben 
" a- Significant petroleum provinces 

Year of first 

discovery in 

this province 

in this country 

Cumulative discoveries in this 

province in this country through 1990 

Significant petroleum province Crude oil 

in 1 00-millionbarrel fields 

(106 bbl) 

Anglo-Paris Basin ...... . ...... . .. . ............ . 

Anglo-Dutch Basin ..... . ............. . . . .. ... . . 

North Sea Graben . . .. . ..... . .... ... . . ..... . . . . . 

Mid North Sea High . . .. . .. ... . .... . . . ..... . ... . 

Vestland Arch .. . . . . . . .... . . . ...... .. . . . ... . .. . 

East Shetland Platform .. . .... .. .. .. .. . . .... . .. . . 

West Shetland Basin ..... . .. . .... . .... . .. . . . ... . 

United Kingdom 

1895 

1939 

1969 

1971 

1972 

1975 

1977 

Total .......... . .. .. .. . .... ... . .. . . .. ........ . . .. . . .. . .. . . . . 

France 

550 

0 

23,083 

120 

0 

542 

800 

25,095 

Aquitaine Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1939 226 

Anglo-Paris Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1954 0 

Total... . . .. .. . ... . ...... . .. . ........ . . ..................... 226 

Northwest German Basin .. . .. . .. . . . .. . ... . . ... . . 

Anglo-Dutch Basin ... . .. .. ........ . ........ .. . . 

North Sea Graben . . ... . ...... .. . .. . .. .. .. . . . . . . 

Netherlands 

1943 

1949 

1968 

385 

232 

0 

Total.. . ... .... . . .. .. . . ........ . ................. . . . .. . ..... 617 

Germany (formerly Federal Republic of Germany) 

Northwest German Basin . . . . . . . . . . . . . . . . . . . . . . . . 1874 666 

North Sea Graben . ...... . ....... . .. . .. . . .. . . ... 1974 0 

Total. .... ... .. ... . ... . . . ... . .. .. .. . ..... .. ..... . ...... .. ... 666 

Norway 

Vestland Arch. . . . ....... . . . . ..... . . . . . .. ...... 1968 

North Sea Graben . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1969 

Norwegian-Danish Basin . . . . . . . . . . . . . . . . . . . . . . . . 1972 

Horda Platform . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . 1979 

Kristiansund-Bodo Fault Complex . . . . . . . . . . . . . . . . . 1981 

Trondelag Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1984 

Voring Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1985 

Total. ... ...... . ....... . . . .... . .. ·. ·· ·· ····················· 

Denmark 

North Sea Graben . ...... .. . . .. ..... . .. . .. ... .. . 1966 

Northwest German Basin . . . . . . . . . . . . . . . . . . . . . . . . 1980 

Total . ..... .. . . . .. . .. . . .. . . . . .... . ......... . . . ....... . ..... . 

Figure 28. Continued. 

1,291 

14,232 

150 

404 

1,228 

428 

138 

17,871 

894 

0 

894 

in all 

fields 

(106 bbl) 

597 

87 

27,325 

240 

50 

742 

840 --

29,881 

512 

316 

-

828 

385 

823 

86 

1,294 

1,944 

0 --

1,944 

1,505 

15,371 

195 

404 

1,345 

464 

138 --

19,422 

1,241 

0 --

1,241 

Gas 

in all 

fields 

oo• ft3

) 

332 

53,748 

39,451 

2 

600 

320 

650 --

95,103 

10,749 

108 --

10,857 

117,224 

26,520 

1,735 

145,479 

33,696 

175 --

33,871 

1,977 

60,526 

35 

44,214 

7,734 

610 

2,685 --

117,781 

6,467 

I --

6,468 
" " 

Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 

400 

~ 350 

~ w 

a: 300 <! 

:::> 

d 

(I) 250 u.. 

0 

(I) 

Cl 200 z 

<! 

(I) 

:::> 150 D 

:I: 

>--

~ 100 <t' 

w 

a: 

<! 50 

1960 1970 1980 

Delineated prospective area 

2000 4000 6000 

CUMULATIVE NUMBER OF WILDCAT WELLS 

1990 

8000 

1950 1960 1970 1980 1990 60,--,------~-------,--------.-----.-----, 

50 

~ 40 X 

~ w 

30 a: 

a: 

<! 

"' z 

::::;- 20 

0 

10 

0~--~--~----~---L----L----L--~--~ 

0 1 00 200 300 400 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Country 

United Kingdom .......... _ ......... .. ......... . .. . 

Ireland ........ ..... ..... .. ........ ... .... . ... .. . . 

France ................... . ......... .. ........... . 

Netherlands .... . ......... .. ................... . .. . 

Belgium ............................. . ........... . 

Luxemburg . . .. . ......... . . ........ ... ....... .. .. . 

~~~:~( : : : : ::: :: : :: :::: ::: : : :: ::: :: :: ::: ::::::: 

Denmark ...... ... ........ .. ......... .. ....... . . . . 

Sweden ....... . ............................... . . . 

Finland ........................................ .. 

Andorra .............. .... .. ...... . ... .... .. .. ... . 

Monaco (not shown) ............................... . 

Greenland 3 

•.•..•.••..•..••.. •• ........ •• .......... 

Iceland (not shown) .......... . .................. . . . 

Land area 

(mi2

) 

93,377 

27,137 

212,736 

13,433 

11,779 

999 

94,905 

124,555 

16,576 

173,394 

130,119 

191 

.5 

840,000 

39,698 

Total ........................................ 1,778,899.5 

Delineated prospective area through 1990: 342,007 mi 2 

Explored area through 1990: 77,207 rni 2 

Wildcat wells through 1990: 7,634 

Current growth in delineated prospective area per wildcat: II rni 2 

Reported discoveries of recoverable crude oil and gas through 1990: 

55.0 x 109 bbl oil and 436 x 1012 cubic feet gas 

Richness total oil discoveries O.l 6 l X 106 bbl/mi2 

total delineated prospective area 

1 Statistics here are for the part of Germany formerly known as the Federal Republic of Germany. Data were not complete for the rest of the country. 2

Norway includes Svalbard. 

'Greenland is listed separately here although it is part of Denmark. Greenland is not shown on the map, and its five wildcat wells and the explored 

and delineated prospective areas defined by them are not included in the data given here. 

Figure 28. Continued. 
" 00 

50N 

45 N 

40 N 

35 N 

30 N 

SPANISH BASINS 

1 1961 Cantabrian Zone 2 1960 North Pyrenean- North Cantabrian Zone 3 19'19 Pyrenean Foothllls 

10 w 5 w 

SWITZERLAND 

ITALIAN BASINS 7 1952 lblelan Platform 8 1952 Pede-A~ Trough 

J==~Zone 

11 1959 Tu.Cany Bu1n 

0 5 E 10 E 15 E 20 E 25 E 30 E 

Figure 29. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of the middle and southern parts of Western Europe. 
Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 160~~--~~------~~------.---------~-----

~ 140 

~ 

~ 120 <t 

=> 

c:l 

"' 100 LL 

0 

"' 0 

z 

<t 

"' 

80 

5 60 :z: 

>--

~ 40 

~ 

~ 20 

Country 

Austria .... . ............ . 

Liechtenstein .......... . . . 

Italy ................ . .. . 

Switzerland ............. . 

Greece ................. . 

Portugal .......... . ... . . . 

Spain .................. . 

Malta ........ . ......... . 

Delineated prospective area 

1000 2000 3000 

CUMULATIVE NUMBER OF WILDCAT WELLS 

4000 

Exploration data 

Land area 

(mi 2

) 

32,381 

65 

116,294 

15,944 

50,147 

35,414 

194,988 

122 

Delineated prospective area through 1990: 

137,179 mi 2 

Explored area through 1990: 29, 133 mi 2 

Wildcat wells through 1990: 3,429 

Current growth in delineated prospective area per 

wildcat: 10 mi 2 

Total. .... · · · · · · · · · · · · · 445,355 

Reported discoveries of recoverable crude oil and 

gas through 1990: 2. 95 X 109 bbl oil and 

30.5 x 10 12 cubic feet gas 

total oil discoveries 

Richness 

total delineated prospective area 

=0.022 X 106 bbUmi2 

::l Figure 29. Continued. 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

3.5 

~ 2.5 X 

~ a: 

~ 

"' 

~ 1.5 __ ,. 

0 

0.5 

1950 1960 1970 1980 1990 

20 40 60 80 100 120 140 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Cumulative discoveries in this 

Significant petroleum 

province 

Year of first 

discovery in 

this province 

in this country 

Austria 

Carpathian Flysch Zone . . . . 1930 

Italy 

Po Basin................. 1866 

lbleian Platform. . . . . . . . . . . 1952 

Caltanissetta Basin . . . . . . . . 1956 

Adriatic Basin . . . . . . . . . . . . 1972 

Total ......... .. ...................... . 

Greece 

North Aegean Sea Basin .... 1971 

Spain 

Catalano-Balearic Basin . . . . 1970 

Malta 

Ibleian Platform. . . . . . . . . . . 1985 

province in this country through 1990 

Crude oil Gas -- in 100-million- in all in all 

barrel fields fields fields 

(106 bbl) (106 bbl) oo• ft3

) 

500 654 1,425 

150 225 15,093 

445 518 144 

144 174 38 

278 360 821 

1,017 1,277 16,096 

172 173 160 

-

159 330 140 

0 35 0 
"" Q 

44 N 

1970 ThraceGallipoli Basin 

Figure 30. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Turkey and Cyprus, Middle East. 
Growth in prospective and explored areas through 1990 

1960 

35 

~ 30 ~ 

w 

0: 

~ 25 

"' u.. 

0 20 "' 0 

z 

<.: 

"' 15 ::> 

0 

:I: 

t-

~ 10 

..:' 

w 

0: 

<.: 

Country 

1970 1980 1990 

Delineated prospective area 

200 400 600 800 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Land area 

(mi2) 

Delineated prospective area through 1990: 

30,168 mi 2 

Turkey . . . . • . . . . . . . . • . . . . 296,184 

Cyprus . . . . . . . . . . . . . . . . . . 3,572 

Explored area through 1990: 6,618 mi 2 

Wildcat wells through 1990: 829 

Total .............. • ... 299,756 

~ Figure 30. Continued. 

Current growth in delineated prospective area per 

wildcat: 7 mi2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 0. 989 X 109 bbl oil and 

1. 18 x 1012 cubic feet gas 

Richness 

total oil discoveries 

total delineated prospective area 

=0.033 X 106 bbUmi2 

~ X 

~ w 

0: 

0: 

<.: 

"' z 

_; 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

1.2 

1.1 

1 

0.9 

0.8 

0.7 

0.6 

0.5 

0.4 

0.3 

0.2 

0.1 

0 

0 10 20 30 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

Cumulative discoveries in this 

province in Turkey through 1990 

Significant petroleum 

province 

Southeast Turkey Basin 

in Turkey 

(Zagros Fold Belt) . . . . . . . . . 1940 

Taurus-Zagros Foothill Belt. . . . 1961 

Total ................................... . 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

210 362 

112 620 - - 322 982 

Gas --

in all 

fields 

< 109 ft3

) 

391 

281 

-

672 
Growth in prospective and explored areas through 1990 

130 

1960 1970 1980 1990 

"' 

120 w 

..... 110 ~ 

w 100 a: 

..: 90 ::::> 

d 

"' 80 LL 

0 

"' 70 0 

2 60 ..: 

"' ::::> 

0 50 

:I: 

1- 40 

~ 30 ..:· 

w 

a: 20 ..: 

32 N 

28 N 

24 N 

20 N 

16 N 

12 N 

35E 

Delineated prospective area 

800 1000 

CUMULATIVE NUMBER OFWILDCATWELLS 

• 

• 

IRAQ-SAUDI ARABIA 

NEUTRAL ZONE 

1938 Arabian Basin, Saudi Ara bla 

SAUDI ARABIA 

1984 .lla'Rib-AI 

40 E 45 E 

1200 

• 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 6oo~r-------~~----------~~-------.---, 

500 

t:~ ~ 

J 200 

0 

100 

• 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

1954 Arabian 

Basin, 

Abu Dhabi 

19'72 

Arabian 

Basin. 

Ra's al Kbaymab 

• • 

YEMEN 

• • 

50 E 

SHARJAH BASIN 1 19'72 Arabian Basin 

U)l.ll AL QA Ylf A YN BASIN 

2 1976 Arabian Basin 

BAHRAIN BASIN 

3 1932 Arabian Basin 

DUBAIBASJN 

4 1966 Arabian Basin 

55 E 60 E 

Figure 31. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of the Arabian 

Peninsula, Middle East. 

82 
Significant petroleum provinces 

Year of first 

discovery in 

this province 

in this country 

Cumulative discoveries in this 

province in this country through 1990 

Significant petroleum province Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

Saudi Arabia 

Arabian Basin . ...... . . . . ... . .. . .... ... ....... . 1938 255,024 

Kuwait 

Arabian Basin ...... . ...... . ... . ... .. ..... .. .. . 1938 110,080 

Former Kuwait-Saudi Arabia Neutral Zone 

Arabian Basin . . .. . .. ... . ... ...... .... . . .. .. .. . 

Arabian Basin ........ . .. ..... .. .. .. ... . .... . .. 

Arabian Basin .. ...... .. .. .. .. . . .. ............ . 

Oman Basin .. . .................. . ....... . .... . 

Arabian Basin . ... . . .. .... . .... .. . .. . . . . .. . .. . . 

1953 

Bahrain 

1932 

Qatar 

1940 

Oman 

1957 

1969 

18,605 

1,005 

8,300 

6,916 

520 

Total. ....................... . ... . . . .. ... . .. . . . . .. .. ....... . 7,436 

Abu Dhabi* 

Arabian Basin .. . . . . .. .. ... . .. .. . . ........ . . . . . 1954 68,652 

Ajman* 

Arabian Basin .......................... . ... . . . 1983 0 

Dubai* 

Arabian Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1966 5, 175 

Umm al Qaywayn* 

Arabian Basin ...... .. ......................... 1976 0 

Ra's al Kbaymab* 

Arabian Basin ... .. . . ... . .. .. .... . ..... .. .. . . .. 1972 1,943 

Sharjah* 

Arabian Basin . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 1972 505 

Ma'Rib-Al Jawf Basin . ...... . .. .. . . .. . . . . ..... . 

Shabwa Basin . ..... . . .. .. .. .. . ......... . ..... . 

Yemen 

1984 

1987 

1,204 

500 

Total. . ...... .. .... . .... ... . . . .. . . .. .. .. .. . . . . .. ... . ... . .... 1,704 

in all 

fields 

(106 bbl) 

255,351 

110,080 

18,609 

1,005 

8,550 

9,379 

762 

10,141 

69,793 

0 

5,195 

0 

1,943 

505 

1,427 

500 

1,927 

Gas 

in all 

fields 

oo• fel 

148,613 

62,226 

11,715 

12,500 

168,565 

9,593 

2,776 

12,369 

129,157 

250 

4,850 

750 

1,293 

7,100 

12,500 

0 

12,500 

*One of the seven United Arab Emirates. (Urnm al Qaywayn is also spelled Ubrn Al Qawai, and Ra's al Khaymah is also spelled Ras Al Khaim.) 

Exploration data 

Country 

Saudi Arabia . . . .. ... . .. .. .. .. ...... . . .. ........... . . 

Kuwait . . . . . . ...... ... . ... .. . . . . . .. . ....... . ....... . 

Iraq-Saudi Arabia Neutral Zone .. .. .................... . 

Bahrain . ....... . .. . ... .. . .. .. . ... . .. .. . ............ . 

Qatar .. ..... .. .. . ..... .... .. .. ....... ............. . 

Oman .. .. ... . .. .. .. . .. . .... . ... . .... ... .. .. .. . . . . . . 

United Arab Emirates2 ••• • • • • • •••.•••. • • •• • ••• • ••••••• 

Yemen .. . ... ... . .. ... . ... .... . . . .. . . ... . ... . .. ... . . 

Land area' 

(m?) 

830,000 

6,880 

1,360 

239 

4,250 

82,000 

32,300 

204,000 

Total .... . .. . . . .. . . . ... . ... . .... . ................. 1, 161,029 

Delineated prospective area through 1990: 116,689 mi2 

Explored area through 1990: 16,745 m? 

Wildcat wells through 1990: 1,002 

Current growth in delineated prospective area per wildcat: 43 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

483 x 109 bbl oil and 572 x 1012 cubic feet gas 

Richness total oil discoveries 4. 140 x 106 bbllm? 

total delineated prospective area 

1 Land areas from World Fact book 1991 (U.S. Central Intelligence Agency, 1991). 2

0utlines of individual emirates in the United Arab Emirates are not shown. 

Figure 31. Continued. 

83 
40 N 

35 N 

30 N 

25 N 

30 E 

d 

LEBANON 

1000 Dead 

Sea Graben 

ISRAEL 

35 E 

JORDAN 

40 E 45 E 

Figure 32. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Syria, Lebanon, 

Israel, and Jordan, Middle East. 

84 
30 

28 en 

UJ 26 ..../ 

~ 24 UJ 

a; 22 <t 

::::> 

d 20 en 

u. 18 0 

en 16 0 

z 14 <t 

en 12 ::::> 

0 

:r 10 .... 

~ 8 

...:· 

UJ 

a; 

<t 

0 

Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 

Delineated prospective area 

Explored area 

X 

~ UJ 

a; 

a; 

<t 

m 

~ 

..... -

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

0 100 200 300 400 4 8 12 16 20 24 28 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Zagros Fold Belt .. .. ... ... .................... . 

Arabian Basin .... .. .. .... ...... .............. . 

Year of first 

discovery in 

this province 

in this country 

Syria 

1956 

1976 

Total ..............•.....•. .... . .... . ..... . ................ • 

Jordan 

Arabian Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1984 

Exploration data 

Cumulative discoveries in this 

province in this country through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

2,687 2,984 

1,601 2,183 

4,288 5,167 

0 50 

Land area Delineated prospective area through 1990: 25,153 mi2 

Country (mil Explored area through 1990: 3,742 mi2 

Syria .................. .. ......................... . . 

Lebanon ............................................ . Wildcat wells through 1990: 383 

Gas 

in all 

fields 

(109 ft3

) 

3,035 

1,015 

4,050 

410 

Israel ................ . ........................... .. . 

Jordan ....... •......... . . ... ................... . .... 

71,227 

3,927 

7,984 

37,264 Current growth in delineated prospective area per wildcat: 155 mi2 

Total . . . . . . • . . . . . . . . . . . • . . . . . . . . . . . . . . . . • . . . . . . . . . 120,402 

Figure 32. Continued. 

Reported discoveries of recoverable crude oil and gas through 1990: 

5.24 x 109 bbl oil and 6.46 x 1012 cubic feet gas 

Richness total oil discoveries 0.208 x 106 bbUmiz 

total delineated prospective area 

85 
40 N 

35 N 1903 Zagros 

Fold Belt 

• 

, .. • ' • • 

• 

tt • 

• • 

• 

30 N • 

25 N 

35 E 40 E 45 E 50 E 

Figure 33. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Iraq, 

Middle East. 

86 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1930 1950 

10 

1960 1970 1990 

"' w 

....J 

~ w 

a: 

<( 

::::> 

0 

"' u.. 

0 

"' Cl 

z 

<( Delineated prospective area 

"' ::::> 

0 

:I: 

.... 

~ 

<(-

w 

a: 

<( Explored area 

0 

0 20 4IJ 60 80 100 

CUMULATIVE NUMBER OF WILDCAT WELLS 

§ 

X 

"' ....J 

w 

a: 

a: 

<( 

"' 

~ 

_; 

0 

120 

120 

110 

100 

90 

80 

70 

60 

50 

4IJ 

30 

20 

10 

1930 1950 1960 1970 1980 1990 

0 L__J __ ~ __ _L __ -L--~--~--~--L-~~_J 

0 2 4 6 8 10 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Zagros Fold Belt .............................. . 

Arabian Basin .................... ............ . 

Year of first 

discovery in 

this province 

in Iraq 

1903 

1948 

Cumulative discoveries in this 

province in Iraq through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

38,673 39,434 

71,885 71,905 

Gas 

in all 

fields 

(109 ft3) 

18,833 

42,035 

Total ................... ............... .. .. .. .............. . 110,558 111,339 60,868 

Exploration data 

Land area: 172,000 mi2 Current growth in delineated prospective area per wildcat: 125 m? 

Delineated prospective area through 1990: 9,550 mi2 Reported discoveries of recoverable crude oil and gas through 1990: 

Ill x 109 bbl oil and 60.9 x 1012 cubic feet gas 

Explored area through 1990: 1,120 mi2 

Wildcat wells through 1990: Ill Richness total oil discoveries 11.658 x 106 bbllmi2 

total delineated prospective area 

Figure 33. Continued. 

87 
45 N 

40 N 

35 N 

30 N 

25 N 

45 E 

1956 Qom Basin 

• • 

1906 Zagros 

Fold Belt 

50 E 

• 

• 

• •• 

IRAN 

55 E 

1968 North 

Afghan Basin 

60 E 

1982 Kopet Dag 

Foredeep 

65 E 

Figure 34. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Iran, 

Middle East. 

88 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 1960 1970 1980 1990 45r------.-------------.-------------,,--, 120r------------.---------------------n---. 

~ 40 -' 

~ 

w 35 a: 

<t 

El 30 en 

.... 

~ 25 Cl 

2 

~ 20 :::> 

Cl i= 15 

~ 

<i 10 w 

a: 

<t 

Delineated prospective area 

Explored area 

oL_~~~==c=~==~==~~ 0 100 200 300 

110 - 100 

8 90 

X 80 ~ w 

a: 70 a: 

<t 60 

~ "' 

..... 50 

0 40 

30 

20 

10 

0 

0 10 20 30 40 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Zagros Fold Belt ............... , . .... . ..... . .. . 

Qom Basin . ... ..... . ........... . .... . ..... . .. . 

Arabian Basin ... .. . ....... . .. .. . ... , ..... , . .. . 

Year of first 

discovery in 

this province 

in Iran 

1908 

1956 

1960 

Cumulative discoveries in this 

province in Iran through 1990 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

89,802 

125 

20,694 

in all 

fields 

(106 bbl) 

90,352 

175 

20,747 

Gas 

in all 

fields 

(109 fel 

554,723 

1,138 

177,588 

Total. ................ . .... . .... .. .... . .................... . 110,621 111,274 733,449 

Land area: 635,000 m? 

Delineated prospective area through 1990: 40,773 m? 

Explored area through 1990: 2,903 m? 

Wildcat wells through 1990: 317 

Figure 34. Continued. 

Exploration data 

Current growth in delineated prospective area per wildcat: 73 mi 2 

Reported discoveries of recoverable crude oil and gas through 1990: 

Ill x 109 bbl oil and 770 x 1012 cubic feet gas 

Richness total oil discoveries 2.473 x 106 bbllmi2 

total delineated prospective area 

89 
~ 20 N 

15 N 

lON 

5 N 

THE 

GAMBIA 

0 

20W 

• 

15 w 10 w 

IVORY COAST 

5 w 

1970 Saltpond 

Basin 

0 

1968 Benin 

Embayment 

1970 Benin 

Embayment 

5 E 

Figure 35. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Senegal, The Gambia, Guinea-Bissau, 

Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo, Benin, and Cape Verde, Africa. Because Cape Verde is west of the area mapped and has no reported 

wells, it is not shown. 
~ 

Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 

10 

(/) 9 

~ .L Delineated prospective area :E 

w 

a: 

<( 

::::> 

Cl 

(/) 

u.. 

0 

(/) 

0 

z 

<( 

(/) 

::::> 

0 

:I: 3 I-

;!; 

~ a: 

<( 

nl ~ I I I I I I I I I 

20 40 60 80 100 120 140 160 180 200 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Country 

&M~ . . .. . . .. ...... .. . .. . .... ..... .......... . ... . . 

The Gambia ....... . .......... ...................... . 

Guinea-Bissau .. ...... .. . . .. ... .. .... . .. . ........ . . . . . 

Guinea .... . .. . . .. ..• ........ .. .. .. . . .... . . .......... 

Sierra Leone ........ ..... ..................... . . . ... . 

Liberia . ... . .... .... . ... . .. . .. ........ .. ..... .. ..... . 

Ivory Coast ... .. .... .. ... . ........... .. . .... . .. . . .. . . 

Ghana .. . . ... ... ....... .. . ..... . ............... . ... . 

Togo .. .... . . .......... .. ..... •.. .. ········ · ·· · ····· 

Benin . . ... .. .. .. .. ..... .. . . .. ... .............. . . . .. . 

Cape Verde (not shown) ........ .. ..... ............... . 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

220 

200 

180 

8 160 

~ 140 w 

~ 120 <( 

~ 100 

_; 80 0 

60 

40 

20 

2 4 6 8 10 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Land area 

(mi2) 

76,084 

4,003 

13,948 

96,900 

27,925 

43,000 

127,520 

91,843 

21,830 

43,484 

1,557 

Delineated prospective area through 1990: 9,680 mi' 

Explored area through 1990: I ,913 mi 2 

Wildcat wells through 1990: 187 

Current growth in delineated prospective area per wildcat: 63 mi 2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.195 x 109 bbl oil and 0.968 x 10 12 cubic feet gas 

Richness total oil discoveries 0.020 X 106 bbl/mi2 

total delineated prospective area 

Total ... . .. .... .. . . .............. ... . .. . .. . ....... 548,094 

Figure 35. Continued. 
92 

20 N 

15 N 

10 N 

5 N 

0 

5 s 

35 E 

ETHIOPIA 

• 

1973 Ogaden Basin~ 

• •• 

KENYA 

40 E 45 E 

• • 

50 E 

Figure 36. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum 

provinces of Ethiopia, Djibouti, Somalia, and Kenya, Africa. 
Country 

Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 4~~--------~~----~~-----r~------r----. 

~ 3.5 

~ 

w 

a: 

<t 

:::> 

~ 2.5 u. 

0 

(/) 

0 

z 

<t 

~ 1.5 0 

:I: 

>-

z 

~ 

~ 0.5 

Delineated prospective area 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Delineated prospective area through 1990: 3,781 mi2 

Explored area through 1990: 603 mi2 

Ethiopia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409,266 

Djibouti . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . 8,492 Wildcat wells through 1990: 131 

Somalia ............... . ........ .. .. . . .. .. . ..... ..... 246,198 

Kenya ...................................... . ....... 223,478 Current growth in delineated prospective area per wildcat: 66 mi2 

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 887,434 Field sizes not available for oil; reported discoveries of recoverable gas 

through 1990: 3.01 X 1012 cubic feet 

Figure 36. Continued. 

93 
94 

0 

5 s 

10 s 

15 s 

1966 Lower 

Congo Basin 

1955 Kwanza 

Basin 

10 E 

ANGOLA 

• 

15 E 20 E 

Figure 37. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of 

Angola, Africa. 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 1960 1970 1980 1990 

18 

(/) 16 ~ Delineated prospective area ~ 

w 14 a: 

..: '8 :::> 12 Cl 

(/) X 

u.. :3 0 10 w (/) a: 0 a: z ..: ..: "' (/) 

:::> ~ 0 _j :I: 

I- 0 

~ 

..:' 

w 

a: 

..: 

200 400 

0~~~~~~~~~~-L-L-L-L-L-L-L~ 

0 2 4 6 10 12 14 16 18 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Significant petroleum province 

Lower Congo Basin ... . .... . . ................. . 

Land area: 481 ,226 mi2 

Delineated prospective area through 1990: 17,021 mi2 

Explored area through 1990: 4,496 mi2 

Wildcat wells through 1990: 457 

Figure 37. Continued. 

Cumulative discoveries in this 

Year of first province in Angola through 1990 

discovery in Crude oil Gas 

this province in 100-million- in all in all in Angola barrel fields fields fields 

(106 bbl) (106 bbl) (109 ft3

) 

1966 3,532 4,518 6,712 

Exploration data 

Current growth in delineated prospective area per wildcat: II mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

4.62 x 109 bbl oil and 6.76 x 1012 cubic feet gas 

Richness total oil discoveries 0.272 x 106 bbl/mi2 

total delineated prospective area 

95 
15 N 

1989 Chad Basin 

10 N 

NIGERIA 

5 N 

• 

0 

0 0 

0 5 E 10 E 15 E 

Figure 38. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Nigeria, Africa. 

96 
Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 

45 

en 40 ~ 

~ 35 

Delineated prospective area 

w 

a:; 

<( 

:::> 30 d 

en 

u.. 

0 25 en 

0 

z 

<( 20 en 

:::> 

0 15 :I: 

>--

~ 

~ 

10 

w 

a:; 

<( 

§ 

>< 

~ w 

a:; 

a:; 

<( 

cc 

~ 

__ ; 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

35 

30 

25 

20 

15 

10 

0~--~--~--~---L---L--~--_J--~~~ 

200 400 600 800 1000 0 10 20 30 40 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA. IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Significant petroleum province 

Niger Delta ................. .. .............. . . 

Land area: 356,599 mi2 

Delineated prospective area through 1990: 40,902 mi2 

Explored area through 1990: 12,245 me 

Wildcat wells through 1990: I ,031 

Figure 38. Continued. 

Cumulative discoveries in this 

Year of first province in Nigeria through 1990 

discovery in Crude oil Gas 

this province in 100-million- in all in all in Nigeria barrel fields fields fields 

(106 bbl) (106 bbl) (109 fel 

1954 22,284 30,499 69,763 

Exploration data 

Current growth in delineated prospective area per wildcat: 15 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

30.5 x 109 bbl oil and 69.8 x 1012 cubic feet gas 

Richness total oil discoveri.es 0 .746 x 106 bbl!me 

total delineated prospective area 

97 
<J:> 

QO 

40 N 

35 N 

30 N 

25 N 

20 N 

5 E 

TUNISIA 

1958 Ghadames 

BaSin 

1958 Atchan 

Uplift 

1984 Atchan 

Saddle 

10 E 

1949 Pelagian Basin 

1958 Sirte 

Basin 

• 

15 E 

• • 

• • • 

LIBYA • 

20 E 

0 

1964 

~ 

Cyrenaica 

Platform 

TUNISIAN BASINS 

1 19'77 Djefara BaSin 

2 1953 East Tunisian 

Platform 

25 E 

Figure 39. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Tunisia and Libya, Africa. 

30 E 
Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 180.---.-----------------~,-------,------,-, 

~ 160 

~ 

~ 140 <( 

:::> Delineated prospective area 

~ 120 u.. 

0 

~ 100 2 

~ 80 :::> 

0 

i= 60 

~ 

~ 40 cc 

<( 

400 

Explored area 

800 1200 1600 2000 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Country Land area 

(mi2) 

Tunisia . . . . . . . . . . . . . . . . . . 48,330 

Libya ................... 679,400 

Total . . .. . .. . .. . .. .. .. . 727,730 

~ F~gure 39. Continued. 

Delineated prospective area through 1990: 

171,114 mi2 

Explored area through 1990: 23,916 mi 2 

Wildcat wells through 1990: 1,889 

Current growth in delineated prospective area per 

wildcat: 46 mi2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 49.0 x 109 bb1 oil and 

33.8 x 1012 cubic feet gas 

total oil discoveries Richness=----------

total delineated prospective area 

=0.286 X 106 bbl/mi2 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

60 

50 

~ 40 X 

~ UJ 

g§ 30 <( 

al 

~ 

... r 20 

0 

10 

20 40 60 80 100 120 140 160 180 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Cumulative discoveries in this 

Significant petroleum 

province 

Year of first 

discovery in 

this province 

·in this country 

Tunisia 

Pelagian Basin . . . . . . . . . . . . 1949 

Ghadames Basin . . . . . . . . . . 1964 

Total . .......... . . . ..... . .. . ... .. ..... . 

Sirte Basin ......... . .... . 

Atchan Uplift ............ . 

Ghadames Basin . .. . . .. . . . 

Pelagian Basin ....... .... . 

Atchan Saddle ........... . 

1958 

1958 

1958 

1971 

1984 

Libya 

Total ............... .... .............. . 

province in this country through 1990 

Crude oil Gas -- in 100-million- in all in all 

barrel fields fields fields 

(106 bbl) (106 bbl) (109 ft 3

) 

336 777 1,940 

793 892 1,611 -- --

1,129 1,669 3,551 

41,462 44,049 22,478 

0 9 1,610 

150 1,269 2,162 

1,250 1,460 3,745 

Ito 230 0 -- -- 43,972 47,017 29,995 
..... 

:5 

40 N 

35 N 

30 N 

25 N 

20 N 

15 w 

ALGERIAN BASINS 1 11156 HUll ll-oud ln,b 2 1ll'16 llelrhir Trough s 1989 lloroccan-Alprian-Tuniaian 

At.!M -' 111111 CUed llya Buln 5 1957 Tllrhemt Uplltl 

llOROCC&Ii BASINS 

II 1932 Rharb Buln 

1 ~7 South Rltan Trou&h 

1967-..uiraSoll80-

10 w 

• 

• # 

1967 Timlmoun 

Buln 

5 w 0 

ALGERIA 

5 E 

11164 Central At.IM 

Graben Zone 

10E 

Figure 40. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Morocco and Algeria, Africa. 

... 

1967 Tlhembol<a Arch 

15 E 
-

Growth in prospective and explored areas through 1990 

110 

"' 100 ~ 

~ 90 w 

80 a: 

<{ 

:::> 

70 d 

"' u_ 

0 60 "' 0 

50 z 

<{ 

"' :::> 

0 40 ::c 

>-- 30 ~ 

w 

~ 20 a: 

<{ 10 

1960 1970 1980 1990 

Delineated prospective area 

Explored area 

00 200 400 600 800 1000 1200 

Country 

Morocco . ... .... ... . ... . 

Algeria ................ . 

Total . ... . .... .. . . ... . 

CUMULATIVE NUMBER OFWILDCATWELLS 

Exploration data 

Land area 

(mi 2

) 

172,104 

919,595 

1,091,699 

Delineated prospective area through 1990: 

98,674 mi2 

Explored area through 1990: II ,815 mi 2 

Wildcat wells through 1990: I, 105 

Current growth in delineated prospective area per 

wildcat: 94 mi 2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 18.5 X 109 bbJ oil and 

157 x 1012 cubic feet gas 

Richness 

total oil discoveries 

total delineated prospective area 

=0.187 X 106 bbl/mi2 

g Figure 40. Continued. 

m 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 20,--------T~------------~------~--.---. 

18 

16 

X 14 

~ 12 a: 

a: 

;a 10 

~ 

_J 

0 

o~--~~--~--~--~--_L __ _L __ _L __ _L __ _L __ ~ 

0 20 40 60 80 100 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

Cumulative discoveries in this 

province in Algeria through 1990 

Significant petroleum 

province 

Hassi Messaoud High . .... . 

Illizi Basin .... . ....... . . . 

Atchan Uplift ........ . ... . 

Oued Mya Basin .. ... .. .. . 

Ghadames Basin .... .. ... . 

in Algeria 

1956 

1956 

1956 

1961 

1963 

Total .............. . .................. . 

Crude oil 

in tOO-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

12,499 12,746 

1,906 2,532 

1,522 1,544 

582 1,099 

130 286 --

16,639 18,207 

Gas 

in all 

fields 

(109 ft 3

) 

22,982 

27,226 

3,661 

702 

3,753 

58,324 
35 N 

30 N 

25 N 

20 N 

25 E 

1969 .Marmarica 

Basin 

1966 Northern 

Egypt Basin 

• • 

1968 Abu Gharadiq , 

Basin 

• 

EGYPT 

30 E 

• 1968 Syrian 

Arc 

• 

35 E 40 E 

Figure 41. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Egypt, Africa. 

102 
Growth in prospective and explored areas through 1990 

50 

1930 1960 1970 1980 1990 

"' w 

-' 

~ 40 Delineated prospective area 

w 

a: 

..: 

::::> 

c::l 

"' u.. 30 0 

"' 0 

z 

..: 

"' 20 ::::> 

0 

:I: 

1-

~ 

..:· 10 w 

a: 

..: 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1930 1960 1970 1980 1990 

12ro--.-------.-------------------,---------ro 

11 

10 

0 L-------~------~-------L------~------~ 

0 20 40 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Significant petroleum province 

Gulf of Suez Basin ...... .. ......... .. ......... . 

Land area: 386,198 rni2 

Delineated prospective area through 1990: 47,540 rni2 

Explored area through 1990: 8,463 rni2 

Wildcat wells through 1990: 994 

Figure 41. Continued. 

Cumulative discoveries in this 

Year of first province in Egypt through 1990 

discovery in Crude oil Gas 

this province in 100-rnillion- in all in all in Egypt barrel fields fields fields 

(106 bbl) (106 bbl) (109 ft3) 

1886 8,101 9,459 4,893 

Exploration data 

Current growth in delineated prospective area per wildcat: 62 rni2 

Reported discoveries of recoverable crude oil and gas through 1990: 

10.3 x 109 bbl oil and 17.4 x 1012 cubic feet gas 

Richness total oil discoveries 0.218 x 106 bbVme 

total delineated prospective area 

103 
104 

0 

5 s 

TANZANIA 

• • • 

10 s 

MALAWI 

15 s 

20 s 

1961 Mozambique Basin 

25 s 

30 s 

28 E 33 E 38 E 43 E 

Figure 42. Delineated prospective areas (gray circles), explored areas (black circles), and 

known petroleum provinces of Tanzania, Malawi, Mozambique, Burundi, and Rwanda, Africa. 
C/) 3.5 

~ ::;;: 

w 

a: 

<t 

:::> 5l 2.5 u. 

C) 

C/) 

Cl 

z 

<t 

C/) 1.5 :::> 

C) 

:I: 

>--

~ 

<t' 

w 

a: 0.5 <t 

0 

Country 

Growth in prospective and explored areas through 1990 

0 

1960 1970 1980 1990 

Delineated prospective area 

m ~ ~ 80 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Land area 

(mi2

) 

Delineated prospective area through 1990: 3,606 mi2 

Explored area through 1990: 491 mi2 

Tanzania ......... . .. .. . . . ... .. . ..... .. ...... . ... .. .. 362,820 Wildcat wells through 1990: 76 Malawi ........ ... ... .. ............... ... ... . ....... 49,177 

Mozambique .......... . .............................. 297,731 Current growth in delineated prospective area per wildcat: 33 mi' Burundi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10,747 

Rwanda.. ... . .. . .... .. . .. ....... .. ... .... ... . ... .. .. 10,169 

Total . ............... .. ...... .... .......... . . . .... 730,644 

Field sizes not available for oil; reported discoveries of recoverable gas 

through 1990: 5.29 x 1012 cubic feet 

Figure 42. Continued. 

105 
15 s 

20 s 

25 s 

, 

30 S 1974 Southwest African 

Coastal Basin 

35 s 

40 s 

10 E 

198'7 Southwest African 

Coastal Basin 

15 E 

• 

NAMIBIA 

• 

• 

ZAMBIA 

•• 

ZIMBABWE 

BOTSWANA 

• 

•• • 

• SOUTH AFRICA 

• 

-· • 

• • • • 

. .. • 4 •• 

20 E 25E 30 E 35 E 

Figure 43. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Swaziland, 

Namibia, Lesotho, Zimbabwe, Zambia, Botswana, and South Africa, Africa. 

106 
Growth in prospective and explored areas through 1990 

1970 1980 1990 

20.----.---------------.---------------,--, 

(/) 18 w 

..... 

~ 16 w 

a: 

~ 14 c::l 

:::: 12 0 

~ 10 z 

<t 

(/) 

:::> 

0 

::t: 

1-

~ 

..:' 4 w 

a: 

<t 

40 

Delineated prospective area 

Explored area 

~~--~ 

80 120 160 200 240 280 

CUMULATIVE NUMBER DFWILDCATWELLS 

~ 

X 

~ w 

a: 

a: 

<t 

"' 

~ 

..... -

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1970 1980 1990 

50 

40 

30 

20 

10 

0~~~~~-L-L-L-L~~~~~L-L-~~~ 

0 2 4 6 8 10 12 14 16 18 20 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SUUARE MILES 

Exploration data 

Country 

Swaziland ...................... .. ...... . . . •..... •... 

Namibia ...... . ..... .. ........ . . . ... . .... . , . ....... . 

Lesotho .. .... ..... .. .......... ..... . ... ....... .. .. . 

Zimbabwe .......................... .... . ... ... .. .. . 

Zambia . ... ....... ..................... . ..•..... ... . 

Botswana ......... .. .......... ... ......... ..... .... . 

South Africa ...... ............ .. ..... .... . ....... .. . 

Land area 

(mi') 

6,704 

317,725 

11,716 

150,338 

288,130 

275,000 

472,000 

Total ........ . .... . . . ... .. ... . . .... . .... •... . ..... 1,521,613 

Figure 43. Continued. 

Delineated prospective area through 1990: 17,564 mi2 

Explored area through 1990: 2,420 mi2 

Wildcat wells through 1990: 282 

Current growth in delineated prospective area per wildcat: 38 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.045 x 109 bbl oil and 4.42 x 1012 cubic feet gas 

Richness total oil discoveries 0 _

002 x 106 bbl!mi2 

total delineated prospective area 

107 
12 N 

8 N 

4 N 

0 

4 s 

8 s 

0 

EQUATORIAL GUINEA 

SAO 

PRINCIPE 

TOME AND < 

• 

4 E 8 E 

CENTRAL AFRICAN REPUBLIC 

CAMEROON 

• 

ZAIRE 

• 

• 

12 E 16 E 20 E 24 E 

Figure 44. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Cameroon, 

Central African Republic, Equatorial Guinea, Gabon, Sao Tome and Principe, Congo, and Zaire, Africa. 

108 
Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

40 

(I) 35 ~ 

~ w 30 a: Delineated prospective area <( 

:::> 

d 

(I) 25 u. 

0 

(I) 

0 20 2 

<( 

(I) 

:::> 15 0 

:I: 

.... 

~ 10 <(-

w 

a: 

<( 

0 

X 

~ w 

a: 

a: 

<( 

C) 

~ 

=· 

0 

1960 1970 1980 1990 

0 200 400 600 800 10 20 30 40 

CUMULATIVE NUMBER OF WILDCAT WELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Significant petroleum province 

Year of first 

discovery in 

this province 

in this country 

Cameroon 

Niger Delta . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 1967 

Equatorial Guinea 

Niger Delta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1984 

Gabon 

Gabon Coastal Basin .... . • .......... _ . . . . . . . . . . . 1956 

Lower Congo Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1971 

Total. . ........ .................. . ........................... . 

Congo 

Lower Congo Basin . . . . . • . . . . . • . . . . • . . . . . • . . . . . 1957 

Zaire 

Lower Congo Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1971 

Exploration data 

Cumulative discoveries in this 

province in this country through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

806 1,608 

0 0 

1,704 2,605 

106 209 

1,810 2,814 

1,409 1,721 

182 342 

Delineated prospective area through 1990: 36,500 mi2 

Country 

Explored area through 1990: 8,308 mi2 

Cameroon .......................................... . 

Central African Republic .... ... . ..... ................ . Wildcat wells through 1990: 843 

Gas 

in all 

fields 

(109 ft3

) 

1,632 

852 

795 

0 

795 

1,185 

74 

Equatorial Guinea .......................... • .....•... 

Gabon ....... . ........ . ....................... . .... . 

183,350 

238,000 

10,824 

102,290 

372 

132,046 

905,063 

Current growth in delineated prospective area per wildcat: 51 mi2 

Sao Tome and Principe .... . ...... ... .. ...... .. . ...... . 

Congo ......................... . ........ . ..... ······ 

Zaire ......... .. .... ........ . .. .. . ......... ········ · 

Total. ... ............................... . ......... 1,571,945 

Figure 44. Continued. 

Reported discoveries of recoverable crude oil and gas through 1990: 

6.49 x 109 bbl oil and 5.67 x 1012 cubic feet gas 

Richness total oil discoveries O.l7S x 106 bbllmi2 

total delineated prospective area 

109 
--

0 

35N 

80 N 

25N 

20 N ~ 

15 N t 

10 N .J. 

I 

6 N 

0 

20W 

• \ • • 1 

• • 

< -·~ 

"- Y""""'"'--\ '"' J 

~L( ( ~ 

15 w 10 w 5 w 0 5 E 

; llli!SRed.Seal!u!n 

NIGER -~ 0 j, CHAD SUDAN 

e 11174 Chad • 1979 l(uglad • - .. 

• 

"~ f ,......l I --/ ' 

rl I "' 

10 E 15 E 20 E 25 E 30 E 35 E 40 E 

Figure 45. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Western Sahara, Mauritania, Mali, Burkina Faso (formerly 

Upper Volta), Niger, Chad, Sudan, and Uganda, Africa. 
Growth in prospective and explored areas through 1990 

1970 1980 1990 

12.--------------r-----------r-------------,, 

(/) 11 

~ 10 ::;: 

w 

cc 

...: 

::::> 

c:::l 

(/) 

u.. 

0 

(/) 

0 

z 

...: 

(/) 

::::> 

0 

:t: 

1-

~ 

~ cc 

...: 1 

0 

0 20 

Country 

Western Sahara .. .. .. . . 

Mauritania .. . .. . . .... . 

Mali . . . .... . ........ . 

Burkina Paso ... . .. . .. . 

Niger . .. ..... .. . . . . . . 

Chad . . .. . . . . ..... .. . . 

Sudan . .... . .. . . . . ... . 

Uganda . ........ . .. . . . 

Total .. .. .. ........ . 

Figure 45. Continued. 

Delineated prospective area 

Explored area 

40 60 80 100 120 140 160 180 200 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Land area 

(mi2) 

102,703 

418,120 

463,500 

106,111 

458,976 

501,000 

967,500 

93,981 

3,111,891 

Delineated prospective area through 1990: 

10,204 mi2 

Explored area through 1990: 1,386 mi 2 

Wildcat wells through 1990: 194 

Current growth in delineated prospective area per 

wildcat: 30 mi2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 0.630 x 109 bbl oil and 

I. 0 I x 10 12 cubic feet gas 

total oil discoveries 

Richness 

total delineated prospective area 

=0.062 X 106 bbl/mi2 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1970 1980 1990 

700.-------------.--------.--------------.-----. 

600 

~ 500 ~ 

X 

~ 400 w 

cc 

cc 

...: 

"'300 

~ 

J 

0 200 

100 

oL-~--~~--~--L--L--~~---L--L--L~ 

0 2 4 6 8 10 12 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Year of first 

discovery in 

this province 

Cumulative discoveries in this 

province in Sudan through 1990 

Significant petroleum 

province 

Muglad Basin . . ... . . . .. . . 

in Sudan 

1979 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

465 

in all 

fields 

(106 bbl) 

499 

Gas 

in all 

fields 

(109 ft 3

) 

0 
0 

• 

• 

5 s 

• 

SEYCHELLES 

10 s • 

COMOROS 

~ 

15 s 

• 

MAURITIUS 

20 s 

25 s 

40 E 45 E 50E 55 E 60 E 65 E 

Figure 46. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Madagascar, 

Mauritius, Seychelles, and Comoros, Africa. 

112 
Country 

~ 3.5 

~ w 

a: 

<t 

::::> 

c:l 

~ 2.5 0 

Cl) 

0 

z 

<t 

Cl) 

B 1.s :I: 

1-

z 

;;)-

~ 0.5 

Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 

Delineated prospective area 

Explored area 

0~~~~=====--_j 0 W W M 80 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Land area 

(rn?) 

Delineated prospective area through 1990: 3,274 rni2 

Explored area through 1990: 369 rni2 

Madagascar .......................................... 227,800 Wildcat wells through 1990: 76 Mauritius . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 809 

Seychelles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . !56 

Comoros . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 820 Current growth in delineated prospective area per wildcat: 59 rni2 

Total ....................... ... .. ..... ..... ..... .. 229,585 Reported discoveries of recoverable crude oil and gas through 1990: 

Field sizes not available 

Figure 46. Continued. 

113 
40 N 

35 N 

30 N 

25 N 

20 N 

60 E 

1960 North Afghan 

Basin 

AFGHANISTAN 

• 

1886 Kirthar 

Axial Belt 

PAKISTAN 

1965 Karachi 

Trough 

• • 

1985 Indus 

Delta 

65 E 

• • 

• 

• ' • 

• ( 

•• 

1952 Indus 

70 E 75 E 

Figure 47. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Afghanistan and 

Pakistan, Asia. 

114 
18 

"' LU 16 -' 

~ 

LU 14 a: 

< 

::::> 

d 12 

"' u.. 

0 10 "' 0 

z 

< 

"' ::::> 

0 

:I: 

1-

~ 

<i 

LU 

a: 

< 

0 

Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

0 

1950 

40 

1960 1970 1980 1990 1950 1960 1970 1980 1990 

0.9 

0.8 

Delineated prospective area 8 0.7 

X 

"' 0.6 -' LU 

a: 

a: 0.5 < "' 

~ 0.4 

J 

0 0.3 

0.2 

0.1 

OL-L-L-L-L-~~~~~-L-L-L-L-L-L~~~ 

80 120 160 200 240 280 0 2 4 6 8 10 12 14 16 18 

CUMULATIVE NUMBER OFWILDCATWELLS DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Significant petroleum province 

Year of frrst 

discovery in 

this province 

in Pakistan 

Cumulative discoveries in this 

province in Pakistan through 1990 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

in all 

fields 

(106 bbl) 

Gas 

in all 

fields 

(109 ft3

) 

Potwar Basin ............... . .. . . . . . ... . .. .. . . . 1915 115 360 2,669 

Country 

Exploration data 

Land area 

(mi2) 

Delineated prospective area through 1990: 16,707 mi2 

Explored area through 1990: 2,928 mi2 

Afghanistan .. ..... .... .. . . .... ..... . .... . .......... . . 250,000 Wildcat wells through 1990: 258 Pakistan .. . . . .. .. • .. . .. • .... • ... . ... . . . ... . .. ........ 310,236 

Total ....... .. . . . . ... . ...... . . . ... . . . . ............ 560,236 

Figure 47. Continued. 

Current growth in delineated prospective area per wildcat: 78 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.8 x 109 bbl oil and 30.6 X 1012 cubic feet gas 

Richness total oil discoveries 0.048 x 106 bbVmi2 

total delineated prospective area 

115 
-a- 35 N 

30 N 

25 N 

20 N 

15 N 

lON 

• • 

5 N 

• 

MALDIVES 

0 

65 E 70 E 75 E 

1957 Himalayan Foot.hllls 

80 E 

1979 Krl8hnaGoda.va.rl Baoln 

BANGLADISH BASJNS 

I 1965 Aralca.n Foot.hllls 

2 1962 Bencai Delta Basin 

DIDIAN BASINS 

3 1974 Arak= Fcolhills 

4 1915 Benpl Basin 

'l'HA!LAND BASINS 

5 1967 Chao Pbraya Baoln 

6 1962 Khorat-Ubol Baoln 

7 1984 Loei Fold Belt 

8 1988 Phetchabun Baoln 

9 1961 Phltsanulok Baoln 

10 1990 Phu Phan Uplift 

11 1973 Thai Baoln 

85 E 90 E 

1933 Bencai 

Basin, 

lllmgladesh 

1 

1980 Andaman-Nicobar 

lnterdeep Baoln 

0 

95 E 

1889 lllzoramlla.nipur Foot.hills 

100 E 105 E 

Figure 48. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Maldives, India, Bangladesh, 

Myanmar (formerly Burma), Thailand, Sri Lanka, Nepal, and Bhutan, Asia. Some explored area is shown for the Maldives, although the islands 

themselves are not shown. 
... 

... 

" 

Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 70 

(I) 

~ 60 

::ii 

w 

rr: 

<( 50 :::l 

d Delineated prospective area (I) 

'-'-

0 40 (I) 

0 

z 

<( 30 (I) 

:::l 

0 

:I: 

>--- 20 ~ 

<(-

w 10 rr: 

<( Explored ar~------

0 

0 200 400 600 800 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Country Land area 

(mi') 

Maldives (not shown). . . . . . 115 

India .................... 1,246,880 

Bangladesh. . . . . . . . . . . . . . . 54,501 

Myanmar. . . . . . . . . . . . . . . . 261,789 

Thailand..... ..... ... . . .. 198,242 

Sri Lanka................ 25,332 

Nepal . . . . . . . . . . . . . . . . . . . 54,000 

Bhutan..... . ............ 19,300 

Total. .............. . .. 1,860,159 

Figure 48. Continued. 

Delineated prospective area through 1990: 

58,014 mi 2 

Explored area through 1990: 8,785 mi 2 

Wildcat wells through 1990: 767 

Current growth in delineated prospective area per 

wildcat: 35 mi 2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 9.44 X 109 bbl oil and 

57.6 x 10 12 cubic feet gas 

Richness total oil discoveries 

total delineated prospective area 

=0.162 X 106 bbl/mi2 

X 

~ w 

rr: 

rr: 

<( 

co 

~ 

_.-

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1Q90 

lOnr--,-------.--------------------------,n 

oL-----~----_L ____ _J ______ ~----~----_J 

0 20 40 60 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

in this country 

Cumulative discoveries in this 

province in this country through 1990 

Significant petroleum 

province 

Crude oil 

India 

Mizoram-Manipur Foothills . 1889 

Assam Basin . . . . . . . . . . . . . 1953 

Cambay Basin . . . . . . . . . . . . 1958 

Narmada Graben.......... 1960 

Bombay Basin...... . ..... 1974 

Cauvery Basin . . . . . . . . . . . . 1979 

Total. ....... ...... .................. ·· 

in 100-millionbarrel fields 

(106 bbl) 

146 

1,395 

835 

600 

4,103 

140 --

7,219 

Myanmar 

Central Burma Basin ... ... . 1902 574 

in all 

fields 

(106 bbl) 

344 

1,585 

1,391 

637 

4,494 

186 --

8,637 

656 

Gas 

in all 

fields 

(109 ft 3

) 

1,360 

1,785 

3,858 

528 

16,278 

326 

24,135 

7,210 
118 

50 N 

45 N 

40 N 

35 N 

30 N 

25 N 

20 N TAIWAN 

15 N 

10 N 

5 N 

0 

115 E 120 E 

•• • 

, 

• 

~ 1969 Ryukyu Arc 

• 

• 

1904 Taihsi Basin 

1904 Taiwan Basin 

PHILIPPINES 

125 E 130 E 

JAPANESE BASINS 

1 1957 Ishikari Basin 

2 1973 Joban Basin 

3 1912 Kanto Basin 

4 1966 Nato Ridge 

5 1867 Niigata Basin 

6 1891 Ton1akor.nai Ridge 

7 1920 Yar.na~ata Basin 

PffiLIPPINE BASIN 

8 1976 Northwest Palawan 

Shelf 

135 E 140 E 

3 

145 E 

Figure 49. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum 

provinces of Taiwan, Philippines, Japan, and South Korea, Asia. 
Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 ~rr-.-----.-----------------.------,r-, 

~ 35 

~ 

~ 30 <( 

::::> 

55 25 u.. 

0 

~ 20 z 

<( 

CIJ 5 15 :I: 

,_ 

;;!;; 10 

~ a: 

<( 

Delineated prospective area 

Explored area 

200 400 600 800 

CUMULATIVE NUMBER DFWILDCAT WELLS 

§ 

X 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1950 1960 1970 1980 1990 500,~,r----~-------------.-------,-----, 

400 

~ 300 

a: 

a: 

<( 

"' ;;!;; 200 __; 

0 

100 

oL---~--~----L----L--~----~---L--~ 

0 10 20 30 40 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Country 

Taiwan ............................................. . 

Philippines ... ............ . ............. . ............ . 

Japan ... . .......... .. ... . .......... .. .............. . 

South Korea ..............................•.....•.... 

13 ,890 

114,830 

141,529 

36,600 

Total ............................................. 306,849 

Figure 49. Continued. 

Delineated prospective area through 1990: 33 ,526 mi2 

Explored area through 1990: 6,201 mi2 

Wildcat wells through 1990: 739 

Current growth in delineated prospective area per wildcat: 62 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.457 x 109 bbl oil and 14.4 x 1012 cubic feet gas 

Richness total oil discoveries 0.014 x 106 bbllmi2 

total delineated prospective area 

119 
~ 

..., 

<::> 

20N 

15 N 

10 N 

5 N 

0 

5 s 

10 s 

15 s 

20 s 

90E 

.I 

0 

19'73lllu-

•• 

DlDONBSWi IIASIIIS 

1 11B7 Borlto - 2111117 Xutellluln 

S !ll'lll llulkerbrook Rldjre 

4 1900 Taralran - 6 19'72 1root llatuna Buln 

95E 100 E 

INDONESIA 

1981 lreot 

.111110 llaloya " }.UflOD!o. Della 

- 6. . 11170 Sllralnlk 

-

105 E 

~ • 

1!11191reot 

lava Bmdn 

110 E 115 E 

\ • 

~~ 1990 &l1a ~ ·=-t c. 

0~ 

1938 Salawatl 

-

111'16 Sen&Jam • - . () 

~,~ t:::> • 

~ [,.~" 1972 Timor -

. "" 

120 E 125 E 130 E 135 E 

Figure 50. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Indonesia, Asia. 

• • 

140 E 145 E 
... 

!:: 

Growth in prospective and explored areas through 1990 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 1960 1970 1980 1990 

160 

~ 140 

~ 

UJ 120 a; 

<( 

::::> 

55 100 u_ 

0 

~ 80 z 

<( 

"' 5 60 ::r: 

1-

~ 40 

;;'ia;; 

<( 

400 

Delineated prospective area 

800 1200 1600 2000 

CUMULATIVE NUMBER DFWILDCATWELLS 

Exploration data 

Land area: 587,330 mi 2 

Delineated prospective area through 1990: 143,351 mi 2 

Explored area through 1990: 25,800 mi 2 

Wildcat wells through 1990: 2,489 

Current growth in delineated prospective area per wildcat: 51.7 mi 2 

Reported discoveries of recoverable crude oil and gas through 1990: 

26.9 x 109 bbl oil and 154.0 x 10 12 cubic feet gas 

Richness total oil discoveries 0 _

188 x 106 bbl/mi2 

total delineated prospective area 

Figure 50. Continued. 

2400 

30 

28 

26 

24 

~ 22 

~ 20 X 

~ 18 

~ 16 a; 

~ 14 

~ 12 

d 10 0 

8 

OL--L __ L__L __ L__L __ L__L __ L__L __ L__L __ L_~--L-~ 

0 

Significant petroleum province 

North Sumatra Basin ....... . .. .. ... . 

East Java Basin ................... . 

South Sumatra Basin ............... . 

Kutei Basin ...................... . 

Tarakan Basin . .. . .. ...... ..... ... . 

Central Sumatra Basin ........ . ... . . 

Salawati Basin .................... . 

Barito Basin ...................... . 

Tiga Putah Arch ... .. ..... . ... .... . 

West Java Basin .................. . 

Sunda Basin ......... . ..... ... . ... . 

West Natuna Basin ........ ... .. ... . 

Malaya Basin ..................... . 

20 40 60 80 100 120 140 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

in Indonesia 

1885 

1888 

1896 

1897 

1900 

1920 

1936 

1937 

1940 

1969 

1970 

1972 

1980 

Cumulative discoveries in this 

province in Indonesia through 1990 

Crude oil 

in 100-million- in all 

barrel fields fields 

(106 bbl) (106 bbl) 

260 711 

100 386 

1,421 2,915 

2,655 3,349 

325 447 

11,397 13,399 

351 724 

137 180 

122 137 

1,812 2,915 

662 1,141 

215 396 

0 138 -- Total............................ . .......... . 19,457 26,838 

Gas 

in all 

fields 

(109 ft 3

) 

25,927 

7,697 

5,386 

29,540 

1,502 

2,060 

493 

66 

0 

6,641 

639 

2,329 

95 ---

82,375 
..... 

"' "' 

10 N 

I I l r N 1ll90 llameoPaJa ....... -

191l1Bozam" 

1989 Central 

5 N 1~ \ _ \~~ Luconia una&u:~~ Pla.tfot"m. -. .. - MALAYSIA ., v ' \" - --- ' 

0 t 

~\ - ~ S:APORE ~ -

I ~ 0 -- !~=~~ 5 s i ~~ """"'"" - 1 I 1 ~~ 

r\........._ 

0 

• 

,10 s t ~~~~ ~ l-

_;. 

15 s 

95 E 100 E 105 E 110 E 115 E 120 E 125 E 130 E 

Figure 51. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Malaysia, Brunei, and Singapore, Asia. 
.... 

Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 50 

(/) 

~ 

:E40 

"' a: 

c{ Delineated prospective area => 

d 

~ 30 0 

(/) 

0 

2 

c{ 

~ 20 0 

:I: 

>--

~ 

<i 10 

a: "' c{ 

0 

0 200 400 600 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Country Land area (mi2) 

Malaysia ................. 126,310 

Brunei . . . . . . . . . . . • . . . . . . 2,220 

Singapore . . . . . . . . . . . . . . . . 220 

Total ................. . 128,750 

Delineated prospective area through 1990: 

43,847 mi2 

Explored area through 1990: 7,283 mi2 

Wildcat wells through 1990: 589 

Current growth in delineated prospective area per 

wildcat: 39 mi2 

Reported discoveries of recoverable crude oil and 

gas through 1990: II. 7 X 109 bbl oil and 

65.3 x 10 12 cubic feet gas 

total oil discoveries Richness 

total delineated prospective area 

=0.266 X 106 bbUmi2 

t:l Figure 51. Continued. 

8 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 14r-.-----------,---------------,-----,----, 

12 

~ 10 

~ 

"' a: 

~ 

"' 2 

.J 

0 

0~----~~----~------~------~--~--~ 

0 w 40 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

in this country 

Cumulative discoveries in this 

province in this country through 1990 

Significant petroleum 

province 

Crude oil 

in 100-millionbarrel fields 

(106 bbl) 

in all 

fields 

(106 bbl) 

Malaysia 

Baram Delta ............. . 

Balingian Basin ..... ..... . 

Malaya Basin ............ . 

1910 

1962 

1969 

Total ..... ... . ............. .. ......... . 

Brunei 

Baram Delta .... ......... . 1913 

1,977 

100 

3,916 

5,993 

3,482 

2,173 

470 

4,559 

7,202 

3,901 

Gas 

in all 

fields 

(109 ft3

) 

5,775 

808 

18,392 

24,975 

19,787 
... 

"' ~ 

10 N I . 

5 N 

1 

0 1 

~ 

' 

PAPUA.. NEW GUINEA ~ 

I ... , -~ 5 s + -....__ 

" 10 s -t- 101511 Fly River \ '--- -<.._.~ 

15 s 

20S 

135 E 140 E 145 E 150 E 

• . 

~ SOLOMON ISLANDS 

' ,~, \ 

~ ~ ~ 

155 E 160 E 165 E 

"' ~ 

NAURU 

VANUATU 

b, 

\.4 

Q 

' • 

170 E 

KIRIBATI 

' 

TUVALU 

FIJI - .._ 

0 

175 E 180 E 

Figure 52. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Papua New Guinea and Oceania, southwestern Pacific. For 

this report, Oceania is considered to consist of Vanuatu (formerly New Hebrides), Tonga, Solomon Islands, Fiji, Nauru, Kiribati, Tuvalu, and Western Samoa. Because Tonga and 

Western Samoa are east of the area mapped and have no reported wells, they are not shown. 
... 

Growth in prospective and explored areas through 1990 

1950 1960 1970 1980 1990 10.------T~~r----T~--~--------~~----. 

~ 

~ 

w 

a: 

..: 

::> 

c::l 

en 

u.. 

0 

en 

0 

z 

..: 

en 

::> 

0 

:X: 

>--

~ 

~ a: 

..: 

0 

0 20 

Country 

Papua New Guinea 1 

Vanuatu ............. . .. . 

Tonga (not shown) ....... . 

Solomon Islands ......... . 

Fiji .................. . . . 

Nauru .................. . 

Kiribati ................. . 

Tuvalu ................ . . 

Western Samoa (not shown). 

Delineated prospective area 

Explored area 

~ W W 100 1W 140 160 

CUMULATIVE NUMBER DFWILDCAT WELLS 

Exploration data 

Land area (mi2) 

182,700 

5,700 

270 

11,458 

7,040 

8 

266 

10 

1,133 

Delineated prosrective area through 1990: 

9,415 mi 

Explored area through 1990: I, 117 mi2 

Wildcat wells through 1990: 135 

Current growth in delineated prospective area per 

wildcat: 136 mi 2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 0.260 X 109 bbl oil and 

7.89 x 1012 cubic feet gas 

Total. . . . . . . . . . . . . . . . . . 208,585 

Richness 

total oil discoveries 

total delineated prospective area 

=0.028 X 106 bbl/mi2 

'Land area for Papua New Guinea is from Webster's New Collegiate DictioMry (G. & C. 

Merriam Company, 1975) . 

~ Figure 52. Continued. 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

300 

280 

260 

240 

w 220 0 

;:; 200 

en 180 

~ 160 a: 

;;!; 140 

~ 120 

g 100 

80 

60 

40 

20 

1950 1960 1970 1980 1990 

OL_ __ L_ __ L_ __ L---~--L---L---L---L---~~ 

0 2 4 6 8 10 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum province 

Year of first 

discovery in 

this province in 

Papua New Guinea 

Cumulative discoveries in this 

province in Papua New Guinea through 1990 

Significant petroleum 

province 

Papuan Fold Belt. ........ . 1956 

Crude oil 

in 100-millionbarrel fields 

oo• bbl) 

140 

in all 

fields 

(106 bbl) 

260 

Gas 

in all 

fields 

oo• ft3

) 

3,975 
30 s 

35 s 

1866 Taranaki Basin 

40 s NEW ZEALAND 

1005 Westland Basin 

45 s 

•• 

• 

• • 

- 1978 Great South Basin 

• 50 s 

165 E 170 E 175 E 180 E 

Figure 53. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of New Zealand, 

southwestern Pacific. 

126 
Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 

14r-------.-------r-----.------------.----. 

"' 

~ 12 

:E 

~ 10 ::::> 

c:l 

"' u.. 

0 

"' 0 

z 

<t 

"' ::::> 

0 

:I: 

1-

~ 

~ a: 

<t 

40 

Delineated prospective area 

Explored area 

80 120 160 200 240 280 

CUMULATIVE NUMBER OF WILDCAT WELLS 

8 

X 

~ w 

a: 

a: 

<t 

"' 

~ 

.J 

0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

150 

140 

130 

120 

110 

100 

90 

80 

70 

2 4 10 12 14 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Exploration data 

Land area: 103,416 mi2 

Delineated prospective area through 1990: 12,442 mi2 

Explored area through 1990: 1,816 mi2 

Wildcat wells through 1990: 259 

Figure 53. Continued. 

Current growth in delineated prospective area per wildcat: 69 mi2 

Reported discoveries of recoverable crude oil and gas through 1990: 

0.124 x 109 bbl oil and 7.08 x 1012 cubic feet gas 

Richness total oil discoveries 0. 010 x 106 bbl!mi 2 

total delineated prospective area 

127 
.... 

"" 00 

5 s 

10 s 

1971llro1rae Bu!n 

15 s t 1.9'11 Qankin Platform • 

\ - .. 1979 Exmouth Plateau 

20 s t 

• 1953 North • •• carnarvon Butn • • 

25 s t • 

AUSTRALIA 

•I 

• • 

30 s 

I -tn.II'A n-..t.'- n-.-1- ~ 

• 

35 s 

40 s 

458 

105 E 110 E 115 E 120 E 125 E 

I ~ 

() 

197• Se.hul Platform 

• 

• • •• 

~-.... .., ~ 

~-. . • ... ISM Amadeua t~«· 

Bu!n :· 

, ~'\,- 4 • • 

• 

••• ISM 

• ErolllllDP Bu!n • 

-· ' .... . · ..... • ~- ... .. ~ .. 

130 E 135 E 140 E 145 E 150 E 

' '" '·\ ~~ 

NEW CALEDONIA 

1968 Clarence--Voret.on Baa1n 

1965 Gunnedah Basin 

1964 Sydney Buln 

1924 G!ppoland Buln 

155 E 160 E 165 E 

Figure 54. Delineated prospective areas (gray circles), explored areas (black circles), and known petroleum provinces of Australia and New Caledonia, southwestern Pacific. New 

Caledonia is an overseas territory of France. 
* c::: 

Ul 

0 

'"d 

0 

.... 

'-0 

'-0 

VJ 

I 

VJ 

+=" 

l'\) 

I 

VJ 

CXl 

'-0 

:::0 

0 

0 

0 

CXl 

... 

Growth in prospective and explored areas through 1990 

1960 1970 1980 1990 220r----r----------.----.----------------.-~ 

en 200 UJ 

_J 

~ 180 UJ 

a: 160 

~ I Delineated prospective area en 140 

:5 120 en 

Cl 

~ 100 en 

g 80 :I: i 60 

~- 40 a: 

<( 20 

o~~~~~L_~~~~--~J--L~--~~-L~ 

0 400 800 1200 1600 2000 2400 2800 3200 

CUMULATIVE NUMBER OF WILDCAT WELLS 

Exploration data 

Country Land area 

(me) 

Australia ................ 2,974,581 

New Caledonia. . . . . . . . . . . 7,200 

Total ................. 2,981,781 

Delineated prospective area through 1990: 

198,354 mi2 

Explored area through 1990: 29,921 mi2 

Wildcat wells through 1990: 3,022 

Current growth in delineated prospective area per 

wildcat: 33 mi2 

Reported discoveries of recoverable crude oil and 

gas through 1990: 6.20 x 109 bbl oil and 

83.7 x 10 12 cubic feet gas 

. total oil discoveries Richness 

total delineated prospective area 

=0.031 X 106 bbl/mi2 

~ Figure 54. Continued. 

6 

§ 

X 

~ 4 UJ 

a: 

a: 

<( 

IXl 3 ~ 

...J0 

Oil discovered through 1990 graphed by the year its field 

location became part of the delineated prospective area 

1960 1970 1980 1990 

OL-~==~--~--~--~--~--~--~--...J---~--....l 

0 40 80 120 160 200 

DELINEATED PROSPECTIVE AREA, IN THOUSANDS OF SQUARE MILES 

Significant petroleum provinces 

Year of first 

discovery in 

this province 

in Australia 

Cumulative discoveries in this 

province in Australia through 1990 

Significant petroleum 

province 

Gippsland Basin . . . . . . . . . . 1924 

North Carnavon Basin...... 1953 

Bonaparte Basin . . . . . . . . . . 1964 

Total ................................. . 

Crude oil Gas 

in 100-million- in all in all 

barrel fields fields fields 

(106 bbl) (106 bbl) (109 fe) 

4,185 4,546 10,844 

454 695 2,773 

176 375 6,779 -- -- --- 4,815 5,616 20,396 

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