U.S. Department of the Interior

U.S. Geological Survey

U.S. Geological Survey Bulletin 2204–
The Pre-Messinian Total Petroleum System of the 

Provence Basin, Western Mediterranean Sea 

By Mark Pawlewicz

U.S. Geological Survey Bulletin 2204–A

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

Gale A. Norton, Secretary

U.S. Geological Survey

Charles G. Groat, Director

U.S. Geological Survey, Reston, Virginia: 2004

This report is only available on-line at:

http://pubs.usgs.gov/bul/b2204-a/

For more information about the USGS and its products:

Telephone: 1-888-ASK-USGS

World Wide Web: http://www.usgs.gov/

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.

Although this report is in the public domain, it contains copyrighted materials that are noted in the text. 

Permission to reproduce those items must be secured from the individual copyright owners.
iii

Contents

Foreword ........................................................................................................................................................ 1

Abstract.......................................................................................................................................................... 1

Introduction ................................................................................................................................................... 2

Province Geology.......................................................................................................................................... 3

Pre-Messinian Total Petroleum System.................................................................................................... 4

Source Rocks ....................................................................................................................................... 5

Thermal History and Petroleum Generation and Migration ......................................................... 5

Traps ............................................................................................................................................................ 5

Seals ............................................................................................................................................................ 6

Reservoir Rocks ............................................................................................................................................ 6

Assessment Unit ........................................................................................................................................... 6

References Cited .......................................................................................................................................... 6

Figures

1. Map showing location of U.S. Geological Survey province boundary for the 

Provence Basin............................................................................................................................ 2

2. Generalized stratigraphic column for the Provence Basin, western Mediterranean Sea.......... 3

3. Seismic section from the Provence Basin .......................................................................................... 4

4. Total petroleum system events chart for the Subsalt Assessment Unit (40680101),

Provence Basin (4068), western Mediterranean Sea............................................................ 6
Foreword

This report was prepared as part of the World Energy 

Project of the U.S. Geological Survey. For this project, the 

world was divided into 8 regions and 937 geologic provinces, 

which were then ranked according to the known oil and gas 

volumes within each (U. S. Geological Survey World Energy 

Assessment Team, 2000). Of these, 76 “priority” provinces 

(exclusive of the United States and chosen for their high ranking) and 26 “boutique” provinces (exclusive of the United 

States and chosen for their anticipated petroleum richness 

or special regional economic importance) were selected for 

appraisal of oil and gas resources. The petroleum geology of 

these priority and boutique provinces is described in this series 

of reports.

The purpose of the World Energy Project is to assess 

the quantities of oil, gas, and natural gas liquids that have the 

potential to be added to reserves within the next 30 years. 

These volumes either reside in undiscovered fields whose 

sizes exceed the stated minimum-field-size cutoff value for the 

assessment unit (variable, but must be at least 1 million barrels 

of oil equivalent) or occur as reserve growth of fields already 

discovered.

The total petroleum system constitutes the basic geologic 

unit of the oil and gas assessment. The total petroleum system 

includes all genetically related petroleum that occurs in shows 

and accumulations (discovered and undiscovered) that (1) has 

been generated by a pod or by closely related pods of mature 

source rock, and (2) exists within a limited mappable geologic 

space, along with the other essential mappable geologic elements (reservoir, seal, and overburden rocks) that control the 

fundamental processes of generation, expulsion, migration, 

entrapment, and preservation of petroleum. The minimum 

petroleum system is that part of a total petroleum system 

encompassing discovered shows and accumulations along with 

the geologic space in which the various essential elements 

have been proved by these discoveries. 

An assessment unit is a mappable part of a total petroleum system in which discovered and undiscovered fields 

constitute a single, relatively homogeneous population such 

that the chosen methodology of resource assessment based on 

estimation of the number and sizes of undiscovered fields is 

applicable. A total petroleum system may equate to a single 

assessment unit, or it may be subdivided into two or more 

assessment units if each unit is sufficiently homogeneous in 

terms of geology, exploration considerations, and risk to assess 

individually. 

A graphical depiction of the elements of a total petroleum 

system is provided in the form of an events chart that shows 

the times of (1) deposition of essential rock units; (2) trap 

formation; (3) generation, migration, and accumulation of 

hydrocarbons; and (4) preservation of hydrocarbons. 

A numeric code identifies each region, province, total 

petroleum system, and assessment unit; these codes are uniform throughout the project and will identify the same type of 

entity in any of the publications. The code is as follows:

Region, single digit 4

Province, three digits to the right of 

region code 4068

Total petroleum system, two digits to 

the right of province code 406801

Assessment unit, two digits to the 

right of petroleum system code 40680101

The codes for the regions and provinces are listed in U.S. 

Geological Survey World Energy Assessment Team (2000).

Oil and gas reserves quoted in this report are derived 

from Petroconsultants’ Petroleum Exploration and Production 

database (Petroconsultants, 1996) and other area reports from 

Petroconsultants, Inc., unless otherwise noted.

The figure in this report that shows boundaries of the 

total petroleum system and assessment units was compiled 

using geographic information system (GIS) software. Political 

boundaries and cartographic representations were taken, with 

permission, from Environmental Systems Research Institute’s 

ArcWorld 1:3 million digital coverage (1992), have no political significance, and are displayed for general reference only. 

Abstract

The Provence Basin is in that portion of the western 

Mediterranean Sea that is deeper than 2 kilometers. The basin 

lies essentially beyond the outer continental shelf, between the 

The Pre-Messinian Total Petroleum System of the 

Provence Basin, Western Mediterranean Sea

By Mark Pawlewicz
countries of France, Italy, and Algeria, the Balearic Islands, 

and the islands of Sardinia and Corsica. It encompasses nearly 

300,000 square kilometers and includes the Rhone River 

submarine fan on the continental slope of southern France. It 

is province 4068 in the World Energy study.

A single, hypothetical, total petroleum system (TPS), the 

Pre-Messinian TPS (406801), was described for the Provence 

Basin. The designation hypothetical is used because there 

is no hydrocarbon production from the basin. The Provence 

Basin is a deep-water Tertiary rift basin in which the geothermal gradients vary regionally. The Red Sea Basin shares 

a similar geologic and thermal history with the rifted western Mediterranean Sea and was used as an analog to better 

understand the genesis of the Provence Basin and as a guide to 

estimating possible undiscovered amounts of hydrocarbons. 

For this assessment the basin was given a potential, at 

the mean, for undiscovered resources of 51 trillion cubic feet 

(1.4 trillion cubic meters) gas, 0.42 billion barrels oil, and 2.23 

million barrels natural gas liquids. 

Introduction 

The Provence Basin is a Tertiary rift basin located 

entirely offshore in the western Mediterranean Sea (fig. 1). 

Although the deep basin is a flat sea floor, it includes the 

Rhone River submarine fan deposited onto and beyond the 

2 Pre-Messinian Total Petroleum System, Provence Basin, Mediterranean Sea

Monaco FRANCE

Corsica

Sardinia

TUNISIA

Gulf of Lion

Provence Basin

Tellian Uplift

Total petroleum system boundary 

EXPLANATION

40°

42°

43°

44°

100 KM ALGERIA

Mediterranean Sea

Rhone River

Menorca

Mallorca (4068)

Italy

Marseille

4°E 5°E 6°E 7°E 8°E 9°E 10°E

41°

39°

38°

37°

Cagliari

Figure 1. Location map showing Provence Basin (4068) regional boundary along 

with that of the Pre-Messinian Total Petroleum System (406801) and Subsalt 

Assessment Unit (40680101). The three boundaries are identical.
continental slope off southern France. The central part of the 

basin is believed to contain a 3–4 km thickness of pre-Messinian age turbidite and pelagic sediments overlain by a 1–2 km 

thick sequence of Messinian (uppermost Miocene) evaporites. 

A Pliocene and Pleistocene pelagic sediment and turbidite 

cover is estimated to add another 1–2 km in thickness (fig. 2). 

The basin as described contains one hypothetical TPS, 

the Pre-Messinian TPS (406801). No data exist on drilling, 

production, or oil chemistry that would support the existence 

or even the possibility of hydrocarbon generation by source 

rocks. However, all other essential geologic elements of reservoir, seal, and overburden rocks that control the fundamental 

processes of generation, expulsion, migration, entrapment, and 

preservation of petroleum in a petroleum system are believed 

to exist.

A TPS was defined for this location using a geologic 

analog, and hydrocarbon resources were assigned based 

on that analog. That precise lithology and thickness of the 

subsalt sediments are unknown necessitated, in the assessment 

process, use of a high risk factor for hydrocarbon charge, to 

limit the confidence of finding any hydrocarbons. The basin 

is considered to be a potential gas province with limited oil 

prospects. 

The Red Sea Basin (Lindquist, 1999) shares a number 

of geologic similarities with the Provence Basin. Both are 

products of tectonic activity in the Oligocene to Miocene, both 

are rift basins with attenuated continental crusts, and both have 

poorly understood variable heat flow from the basement. The 

two basins have extensive evaporite deposits and salt domes. 

The differences are also significant: the Red Sea Basin is 

a proven oil and gas producer, whereas the Provence Basin 

presently has no production. Much remains to be learned 

about the Provence Basin.

Province Geology

The TPS boundary coincides with the province boundary (fig. 1). It is drawn on or near the base of the continental 

slopes of France, Algeria, Corsica, Sardinia, and the Balearic 

Islands. The Rhone River submarine fan, which covers the 

continental slope offshore southern France, is included. The 

southwestern portion of the western Mediterranean between 

Africa and the Balearic Islands is not included. 

The break-up of Pangea was initiated during Late Triassic, and crustal separation between the Eurasian and AfroArabian continents occurred in Jurassic time, creating the 

Tethys seaway. The two continental blocks converged during 

the Cretaceous and early Cenozoic, resulting in continental 

shortening and mountain building by stacking; by the end 

of the Eocene, the Tethys seaway had nearly disappeared. In 

the Oligocene the convergence direction between Africa and 

Eurasia was altered by north-south compression and dextral 

oblique slip due to the spreading of the North Atlantic Ocean. 

By late Eocene to early Miocene time, the initial rifting which 

was to form the western Mediterranean had occurred. The 

islands of Corsica and Sardinia were rotated counterclockwise 

away from the European continent, creating the Gulf of Lion 

south of France. In the middle and late Miocene, the Provence 

Basin formed, as seafloor spreading progressed, with 2–4 km 

of a distinct syn-rift rock sequence developing. Evident on 

seismic sections (fig. 3), the post-rift sequence is composed 

of sandy shales, overlain by a distinct unconformity (Cravatte 

Province Geology 3

Figure 2. Generalized stratigraphic column for the Provence Basin, western Mediterranean Sea.

 Thickness Erathem System Series Unit Lithology 

 (km)

 Cenozoic Quaternary- Pleistocene-Pliocene Post-Messinian Shales and 

 Tertiary turbidites

 1–2

 1–2 Cenozoic Tertiary Uppermost Miocene Messinian Evaporites

 3–4 Cenozoic Tertiary Lower Miocene Pre-Messinian

Turbidites 

and pelagic 

sediments, 

including 

sapropels.

Potential 

source and

reservoir

rocks

 2–4 ? Cenozoic Tertiary Rifted 

basement

Figure 2. Generalized stratigraphic column for the Provence Basin, western Mediterranean Sea.
and others, 1974). The sequence is dominated by clastics and 

includes lower Miocene shales and sandstones from turbidites 

(Burrus and Audebert, 1990; Hsü and others, 1978). Evaporite deposition, which included anhydrite, halite and potash, 

occurred: as much as 2 km was deposited in the deep basin; 

carbonates were deposited in shallower regions. During the 

Messinian of uppermost Miocene, the Mediterranean was 

closed off to open-marine circulation; excessive evaporation 

created a major regression that exposed the entire Mediterranean margin to erosion. During the Pliocene and Pleistocene, 

the seas returned to the Mediterranean region, ending evaporite deposition. Overlying the evaporites is a Pliocene and 

Quaternary shale and turbidite sequence. Subsidence of the 

basin continues today and is believed to result from cooling of 

the oceanic lithosphere and (or) from sediment loading (BijuDuval and others, 1978). 

The deep Provence Basin (>2.5 km) has not been 

explored for petroleum because current technology limits 

deep-sea exploration to about 2 km water depth. The shelf 

area of the Gulf of Lion has been drilled with limited success, 

with some production ongoing in the near offshore. DSDP 

leg 42A (Kidd and others, 1978) drilled several holes through 

thin salt deposits on the perimeter of the basin. DSDP drilling 

legs 13 (1973) and 42A (Kidd and others, 1978) penetrated 

interbedded evaporites (anhydrite and gypsum) and dolomitic 

marls. Concern about drilling into the thicker deposits without 

blowout prevention equipment precluded further drilling. 

Pre-Messinian Total Petroleum System

For the World Energy 2000 Assessment, the Provence 

Basin was assessed as one hypothetical TPS, the Pre-Messinian (406801), with one assessment unit, the Subsalt AU 

(40680101) (fig.1). The presence of hydrocarbons is speculative. Within the TPS no hydrocarbons have been located. 

Seeps are not known. 

The entire pre-Messinian stratigraphic section is expected 

to contribute to the eventual production of gas and oil (figs. 

2, 3). The block-faulted region above and including the 

basement should be the most favorable location in the basin 

for gas. All of the pre-Messinian subsalt section is possibly 

within the maturation window for gas. Because of the different geothermal gradients involved, disparities in generation on 

both local and subregional scales may exist, such that mature 

source rock may be localized as separate pods. The distribution, quantity, and quality of the organic matter in the sediments will also have a significant effect on any generation and 

type of hydrocarbon product. It is possible that biogenic gas 

will make up a portion of the anticipated hydrocarbons from 

this province.

Salt diapirs are present at the bottom of the Rhone River 

submarine fan slope and along the west side of the province 

boundary. Such structures are well known to be excellent 

hydrocarbon traps. Beneath the evaporite layer, the conditions 

to generate and trap hydrocarbons could exist within any part 

of the stratigraphic column.

4 Pre-Messinian Total Petroleum System, Provence Basin, Mediterranean Sea

km/s

Messinian

Miocene

SALT 

EAST

2 3 4 5 6 

France

Sardinia

Corsica

Minorca

Post-Messinian

 sediments

WEST

Figure 3. Seismic cross section from the Provence Basin showing salt domes formed from Messinian evaporate deposits. Bar on index 

map shows location of section. Highlighted section shows bottom of salt layer. Modified from Finetti and Morelli (1973).
Source Rocks 

Organic-rich sediments have been described from several 

locations in the Mediterranean. Nesteroff (1973), Kidd and 

others (1978), and Sigl and others (1978) have described 

sapropels, or organic-rich muds, from the eastern Mediterranean. Kidd and others (1978) provided a working definition 

for sapropel: “a discrete layer greater than 1 cm in thickness, 

set in open marine pelagic sediments and containing greater 

than 2.0 percent organic carbon by weight” (p. 422). Sapropels are thought to be deposited under euxinic bottom conditions corresponding to stagnant phases of a basin. Miocene 

to Pleistocene age piston core samples collected during DSDP 

leg 42A from the eastern Mediterranean Sea, southeast, south, 

and southwest of Greece, and just west of Cyprus, contained 

kerogen which ranged as high as 5 percent in layers 1–3 

cm thick (Deroo and others, 1978). Nesteroff (1973) also 

described Quaternary-age turbidites containing sapropels 

from the eastern Mediterranean Sea south of Greece. These 

samples contained kerogen in concentrations as high as 5 percent. Although sapropels have not been found in the western 

Provence Basin, sampling has yet to penetrate the thick Messinian evaporites.

Sediment accumulation is generally facilitated by proximity to sources, and thicker, richer source rocks are often 

deposited closer to the continental slope. At the basin center, 

farther from a sediment source, the rocks would most likely 

be fine-grained pelagic deposits, although turbidites can reach 

long distances onto the abyssal plain. Richards and others 

(1998) noted that mud-rich submarine fans, one constituent of 

a range of deep-marine clastic systems, have a high transport 

efficiency and can have a transport radius of as much as 3,000 

km. The efficiency drops with increasing sediment grain size. 

Source rocks for the Provence Basin could be any or all 

of the following: turbidite sequences, pelagic sediments, or 

carbonate rocks. Of these rock/facies types, turbidites seem 

to offer the best source rock possibilities (Pettingill, 1998a, 

b). Pelagic sediments are not known to be prolific oil and gas 

generators; their potential in the Provence Basin remains to be 

established. Carbonate rocks can be good source rocks, but 

their potential is highly variable.

Stratigraphically, source rocks could occur over the entire 

pre-Messinian sedimentary column. Syn-rift sedimentation 

may incorporate source material for hydrocarbon generation. 

Geophysical profiles show grabens with thick accumulations of sediment next to grabens that appear to be starved of 

sediment. Episodic sedimentation would suggest an unequal 

distribution of any type rock, at least, within the block-faulted 

basement. 

Without yet being identified, reservoirs (or potential 

ones) can be expected geographically nearly anywhere 

throughout the basin. One prospective situation is within the 

southwest-northeast-trending basement fault blocks, which 

extend over a large part of the basin.

Thermal History and Petroleum Generation 

and Migration

The 1–2 km thick Messinian evaporites overlain by a 

1–2 km thick post-Messinian sediment column constitute a 

significant portion of the overburden throughout the basin; 

no specific rock unit can be described (figs. 2, 3). Additionally, the thickest part of the Pliocene and Pleistocene is in the 

northern part of the basin associated with the Rhone River fan. 

The evaporite cover probably has a greater thickness towards 

the middle of the basin and thins towards the basin margins. 

The overburden is apparently the Messinian salt plus the postMessinian turbidites. 

The sediments beneath the evaporite cover are estimated 

to be as much as 4 km thick. Combined with the 2–4 km of 

Messinian and post-Messinian sediments, overburden alone 

is sufficient to raise the thermal maturity of the pre-evaporite rocks into the oil, or perhaps, gas window. This may be 

dependent on location. Burrus and Foucher (1986) showed 

that the geothermal gradient as sampled throughout the entire 

basin is highly variable, in a range of from 46° to 95°C/km, 

and increases from northwest in the Gulf of Lion to southeast 

at Sardinia. This variation is believed to be due to an asymmetrical distribution in the subcrustal heat flow, which, in turn, 

may be the result of magmatic activity. Burrus and Audebert 

(1990) believed that deposition of the low-permeability Messinian evaporites caused an undercompaction of the subsalt 

shales that then would have a lower thermal diffusivity and 

thus higher temperatures. This would increase the possibility 

of the pre-Messinian shales becoming a hydrocarbon source. 

The evaporites, despite their high thermal conductivity, along 

with the post-Messinian sediments and the higher geothermal 

gradient, should provide sufficient cover to allow the thermal 

maturity of the shales to progress in a relatively short time. 

Most if not all of the sediment thickness is expected to be 

within the generative window for gas, and locally, oil.

Two obvious migration paths are (1) vertical, along the 

fault planes in the basement and near-basement; and (2) both 

lateral and vertical through porous facies and possibly syndepositional slumps in the essentially flat lying rocks above 

the basement faulting.

Traps

Traps are expected to be present over much of the 

block-faulted basement. Formed during crustal attenuation 

and rifting, faults are expected to form the most common and 

largest traps in the basin. These horst and graben structures 

extend across the basin and were covered or sealed by post-rift 

sedimentation. Within the post-rift sediments, stratigraphic 

and facies changes are expected to be the prevalent trap style. 

There is no way to estimate the volume, extent, or closure of 

these traps, which will vary laterally, and vertically depending 

on their extent and depositional environment. The timing of 

trap development is early Miocene through the present. 

Pre-Messinian Total Petroleum System 5
6 Pre-Messinian Total Petroleum System, Provence Basin, Mediterranean Sea 

Seals 

Without question the 1–2 km thick Messinian evaporites 

form an extraordinary seal that appears to blanket the entire 

basin. Below the evaporites hydrocarbon seals may exist but 

are less obvious on either a small or a large scale. Smaller 

scale salt or evaporite layers may also occur within the preMessinian sediments. Some shale units within predominantly 

pelagic sediments and within turbidites are also expected to 

act as seals. 

Reservoir Rocks

 Reservoir rocks are expected to be sandstones. Turbidites 

commonly contain sandstone bodies along the margins of the 

basin, along the continental slope, and perhaps into the center 

of the basin. Frequency and size of carbonate reservoirs are 

probably secondary to those of sandstone reservoirs.

Assessment Unit

One AU, summarized in figure 4, Subsalt AU 

(40680101), was identified for the Provence Basin. It encompasses the entire sedimentary column beneath the Messinian 

evaporite cover. The basin is considered to be nearly exclusively a gas province with very little potential for oil. With 

a risk factor that severely limits the probability of resources, 

the AU was estimated to contain, at the mean, undiscovered 

resources of 51 trillion cubic feet of gas, 0.42 billion barrels 

oil, and 2.23 million barrels natural gas liquids.

References Cited

Biju-Duval, B., Letouzey, J., and Montadert, Lucien, 1978, 

Variety of margins and deep basins in the Mediterranean, in

Watkins, J.S., Montadert, Lucien, and Dickerson, P.W., eds., 

Geological and geophysical investigations of continental 

margins: American Association of Petroleum Geologists 

Memoir 29, p. 293–318. 

Burrus, J., and Foucher, J.P., 1986, Contribution to the thermal 

regime of the Provencal Basin based on flumed heat flow 

surveys and previous investigations: Tectonophysics, v. 

128, p. 303–334.

Burrus, Jean, and Audebert, Francois, 1990, Thermal and 

compaction processes in a young rifted basin containing 

evaporates—Gulf of Lions, France: American Association 

of Petroleum Geologists Bulletin, v. 74, p. 1420–1440.

Cravatte, J., Dufaure, P., Prim, M., and Rouaix, S., 1974, Les 

sondages du Golfe du Lion, stratigraphie et sedimentologie: 

Notes Memoir, v. 2, p. 209–274.

Deroo, G., Herbin, J.P., and Roucache, J., 1978, Organic 

geochemistry of some Neogene cores from sites 374, 375, 

377 and 378; leg 42A, eastern Mediterranean Sea, sedimentology and environmental conditions of sapropels, in

PRESERVATION

GENERATIONTRAP FORMATION

MIGRATIONACCUMULATION

100

50

150

Cretaceous

Paleogene

65

144

Neogene

24

Pal

Eoc

Olig

Mio

Plio

Geologic 

Time 

Scale Petroleum

System Events

0

OVERBURDEN ROCK

SEAL ROCKS

RESERVOIR ROCK

SOURCE ROCK

Figure 4. Total petroleum system events chart for the Subsalt Assessment Unit (40680101), Provence Basin (4068), western Mediterranean Sea. Time scale in millions of years.
References Cited 7

Hsü, K.J., Montadert, Lucien, and others, eds., Initial 

reports of the Deep-Sea Drilling Project, Volume XLII, part 

1: Washington, D.C., U.S. Government Printing Office, p. 

465–472.

Environmental Systems Research Institute Inc., 1992, ArcWorld 1:3M digital database: Environmental Systems 

Research Institute, Inc. (ESRI), available from ESRI, Redlands, Calif., scale 1:3,000,000.

Finetti, I., and Morelli, C., 1973, Geophysical exploration of 

the Mediterranean Sea: Bollettino di Geofisica Teorica ed 

Applicata, v. XV, p. 263–344.

Hsü, K.J., Montadert, Lucien, Bernoulli, Daniel, Cita, M.B., 

Erickson, Albert, Garrison, R.E., Kidd, R.B., Melieres, 

Frederic, Müller, Carla, and Wright, Ramil, 1978, History 

of the Mediterranean salinity crisis, in Hsü, K.J., Montadert, Lucien, and others, eds., Initial reports of the Deep-Sea 

Drilling Project, Volume XLII, part 1: Washington, D.C., 

U.S. Government Printing Office, p. 1053–1079.

Kidd, R.B., Cita, M.B., and Ryan, W.B.F., 1978, Stratigraphy 

of eastern Mediterranean sapropels sequences recovered 

during DSDP Leg 42A and their paleoenvironmental significance, in Hsü, K.J., Montadert, Lucien, and others, eds., 

Initial reports of the Deep Sea Drilling Project, Volume 

XLII, part 1: Washington, D.C., U.S. Government Printing 

Office, p. 421–443.

Lindquist, S.J., 1999, The Red Sea Basin province—SudrNubia and Maqna petroleum systems: U.S. Geological 

Survey Open-File Report 99–50–A.

Nesteroff, W.D., 1973, Petrography and mineralogy of sapropels, in Ryan, W.B.F., Hsü, K.J., and others, eds., Initial 

reports of the Deep-Sea Drilling Project, Volume XIII:

Washington, D.C., U.S. Government Printing Office, p. 

713–720.

Petroconsultants, 1996, Petroleum exploration and production 

database: Petroconsultants, Inc., Houston, TX 77274-0619, 

U.S.A., or Petroconsultants, Inc., Geneva, Switzerland.

Pettingill, H.S., 1998a, World Turbidites–1& 2—Turbidite 

plays’ immaturity means big potential remains: Oil and Gas 

Journal, October 5, p. 106–112. 

Pettingill, H.S., 1998b, World Turbidites–1& 2—Turbidite 

plays’ immaturity means big potential remains: Oil and Gas 

Journal, October 12, p. 93–97.

Richards, M., Bowman, M., and Reading, H., 1998, Submarine-fan systems 1—Characterization and stratigraphic 

prediction: Marine and Petroleum Geology, v. 15, no. 7, p. 

689–717.

Sigl, Walter, Chamley, Herve, Fabricius, Frank, Giroud 

d’Argoud, Ghislaine, and Muller, Jens, 1978, Sedimentology and environmental conditions of sapropels, in Initial 

reports of the Deep-Sea Drilling Project, Volume XLII, part 

1: Washington, D.C., U.S. Government Printing Office, p. 

445–465.

U.S. Geological Survey World Energy Assessment Team, 

2000, U.S. Geological Survey world petroleum assessment 

2000—Description and results: U.S. Geological Survey 

Digital Data Series DDS-60, 4 CD-ROMs.

Published in the Central Region, Denver, Colorado

Manuscript approved for publication November 18, 2003

Graphics by Mark Pawlewicz 

Photocomposition by William Sowers

Edited by L. M. Carter