The U.S. Exclusive Economic 

Zone A Summary of its 

Geology, Exploration, and 

Resource Potential 

GEOLOGICAL SURVEY CIRCULAR 912 Publlo Inquiries O:f':f'ice 

s .. Geological Survey 

.? .,_;4 ~Uf3tom House 

555 Ba ttery Street 

San Francisco, California 94111 

• 

·' 

• 

The U.S. Exclusive Economic 

Zone A Summary of its 

Geology, Exploration, and 

Resou r·ce Potential 

By Robert W. Rowland, Margaret R. Goud, and 

Bonnie A. McGregor 

GEOLOGICAL CIRCULAR 912 

1983 
United States Department of the Interior 

JAMES G. WATT, Secretary 

Geological Survey 

Dallas L. Peck, Director 

Library of Congress catalog card No. 83-600597 

Free on application to Branch of Distribution, U.S. Geological Survey 

604 South Pickett Street, Alexandria, VA 22304 
CONTENTS 

Introduction ----------------------------------------------------------------------------------------------- 1 

Ackno\\rledgments ------------------------------------------------------------------------------------------ 1 

Description and history of the EEZ ---------------------------------------------------------------------- 1 

Geology ------------------------------------------------------------------------------------------ 2 

Resource potential of the EEZ --------------------------------------------------------------------- 5 

Oil and gas resources -------------------------------------------------------------------- 5 

Atlantic region ---------------------------------------------------------- 7 

Gulf of Mexico region ---------------------------------------------------------- 8 

Pacific region -------------------------------------------------- 8 

Alaska region ------------------------------------------- 9 

Island regions ------------------------------------ 11 

Hard-mineral resources ------------------------------------- 11· 

Polymetallic sulfides ------------------------------------ 12 

Cobalt-rich manganese crusts and nodules ---------------------------------------- 15 

Exploration methods ---------------------------------------- 16 

Seismic reflection ---------------------------------- 16 

Long range side-scan sonar (GLORIA) -------------------------------------- 16 

Wide-angle multibeam echo sounding (Seabeam) ---------------------------------------- 17 

Midrange side-scan sonar (Sea MARC) --------------------------------------------- 17 

Conclusion ----------------------------------------- 18 

References ------------------------------------------- 19 

Appendix A: White House press release ------------------------------------------------- 2 4 

Appendix B: White House fact sheet ----------------------------------------------- 26 

Appendix C: 'I1le continental shelf, article 76, Third United Nations Conference on the Law of 

the Sea ----------------------------------- 2 8 

III 
THE WHITE HOUSE 

Office of the Press Secretary 

Embargoed for release at 4:00 pm EST March 10, 1983 

EXCLUSIVE ECONOMIC ZONE OF THE UNITED STATES OF AMERICA 

A PROCLAMATION BY THE PRESIDENT OF THE UNITED STATES OF AMERICA 

WHEREAS the Government of the United States of America desires to facilitate the wise 

development and use of the oceans consistent with international law; 

WHEREAS international law recognizes that, in a zone beyond its territory and adjacent 

to its territorial sea, known as the Exclusive Economic Zone, a coastal State may assert certain 

sovereign rights over natural resources and related jurisdiction; and 

WHEREAS the establishment of an Exclusive Economic Zone by the United States will 

advance the development of ocean resources and promote the protection of the marine environment, while not affecting other lawful uses of the zone, including the freedoms of navigation 

and overflight, by other States; 

NOW, THEREFORE, I, RONALD REAGAN, by the authority vested in me as President of the Constitution and laws of the United States of America, do hereby proclaim the 

sovereign rights and jurisdiction of the United States of America and confirm also the rights 

and freedoms of all St~tes within an Exclusive Economic Zone, as described herein. 

The Exclusive Economic Zone of the United States is a zone contiguous to the territorial 

sea, including zones contiguous to the territorial sea of the United States, the Commonwealth 

of Puerto Rico, the Commonwealth of the Northern Mariana Islands (to the extent consistent 

with the Covenant and the United Nations Trusteeship Agreement), and United States overseas territories and possessions. The Exclusive Economic Zone extends to a distance 200 nautical miles from the baseline from which the breadth of the territorial sea is measured. In cases 

where the maritime boundary with a neighboring State remains to be determined, the boundary of the Exclusive Economic Zone shall be determined by the United States and other State 

concerned in accordance with equitable principles. 

Within the Exclusive Economic Zone, the United States has, to the extent permitted by 

international law, (a) sovereign rights for the purpose of exploring, exploiting, conserving and 

managing natural resources, both living and non-living, of the seabed and subsoil and the superjacent waters and with regard to other activities for the economic exploitation and exploration 

of the zone, such as the production of energy from the water, currents and winds; and (b) jurisdiction with regard to the establishment and use of artificial islands, and installations and structures having economic purposes, and the protection and preservation of the marine environment. 

The Proclamation does not change existing United States policies concerning the continental shelf, marine mammals and fisheries, including highly migratory species of tuna which are 

not subject to United States jurisdiction and require international agreements for effective 

management. 

The United States will exercise these sovereign rights and jurisdiction in accordance with 

the rules of international law. 

Without prejudice to the sovereign rights and jurisdiction of the United States, the Exclusive Economic Zone remains an area beyond the territory and territorial sea of the United 

States in which all States enjoy the high seas freedoms of navigation, overflight, and laying of 

submarine cables and pipelines, and other internationally lawful uses of the sea. 

IN WITNESS WHEREOF, I have hereunto set my hand this tenth day of March, in the 

year of our Lord nineteen hundred and eighty-three, and of the Independence of the United 

States of America _the two hundred and seventh 

RONALD REAGAN 

Accompanying the release of this proclamation were a statement by the President (Appendix A) and 

an oceans policy fact sheet (Appendix B). 
The U.S. Exclusive Economic Zone- A Summary of its 

Geology, Exploration, and Resource Potential 

By Robert W. Rowland, Margaret R. Goud, and Bonnie A. McGregor 

INTRODUCTION 

On March 10, 1983, President Ronald Reagan 

signed a proclamation establishing the Exclusive 

Economic Zone (EEZ), an area contiguous to the 

territorial sea of the United States, the Commonwealth of Puerto Rico, the Commonwealth of the 

Northern Mariana Islands, and the U.S. overseas 

territories and possessions. The EEZ area is approximately 3. 9 billion acres. In comparison to the 

2.3 billion acres of related onshore area, the EEZ 

proclamation brings within the national domain an 

enormous new frontier area in which the types of 

energy and mineral resources present are fairly 

well known but which are still largely unassessed 

in terms of the abundance and recoverability. The 

purpose of this report is to (1) summarize the geology of the EEZ sea floor, (2) specify the known 

geologic resources of the EEZ, and (3) describe 

geophysical and sampling techniques which can be 

used to map the EEZ and estimate its resource potential. Figure 1 outlines the extent of the EEZ, 

and figure 2 shows a schematic diagram of the 

boundaries. 

ACKNOWLEDGMENTS 

The motivation and guidance for this report 

were provided by A. F. Holser. Reviews by N. T. 

Edgar and T. W. Offield significantly improved the 

text. Throughout the development of this report, 

we benefited from the aid and advice of S. B. Griscom, G. D. Hardin, T. A. Landry, and W. C. 

Schwab. 

1 

DESCRIPTION AND HISTORY OF THE EEZ 

The legal basis for U.S. offshore jurisdiction 

was set in the Presidential Proclamation of September 28, 1945, which recognized that "the continental shelf may be regarded as an extension of 

the land-mass of a coastal nation and thus naturally 

appurtenant to it" (Proclamation No. 2667, 59 Stat. 

884). At that time an offshore depth of 600 feet was 

assumed to be the outer limit of technology for resource exploitation. Later, the Outer Continental 

Shelf Lands Act of 1953 recognized the Outer Continental Shelf as "all submerged lands lying seaward of [state waters] . . . which are subject to 

[United States] jurisdiction and control," without 

defining the outer limit of U.S. jurisdiction. The 

1958 United Nations Convention on the Continental Shelf defined the outer limit as "a depth of 200 

metres or beyond that limit to where the depth of 

the superjacent waters admits exploitation of the 

natural resources." This convention became effective for the U.S. in 1964. Thus the seaward extent 

of the U.S. has never been clearly defined either in 

a geologic or in a legal sense, although since 1945 

the concept of an extension of the land mass has 

been in place. The term continental shelf has been 

used domestically and internationally at the Third 

United Nations Conference on the Law of the Sea 

(UNCLOS) to include continental and insular 

shelves, slopes, rises, and other features such as 

continental borderlands (see fig. 3). International 

law also recognizes that the continental shelf usually extends a minimum of 200 nautical miles, regardless of geology. 
. Midway Island ,-;_ 

! .. "'--.. ', .. - ........ 

...... _ . ......, 

30 

Mariana 

Islands\,....\ 

(\. \ l • 1 

Guam 1 ·

1 1 

Wake 

Island;<,....,. 

! . ) 

""' 

""" .. ·- \ Johnston r "'\ ._'-.. •/Hawaii 

Island -+- · .

1 ' _,.... \'· I - _, \,_: 

/ \ 

HowlandX: J 

Island '-,.... 

(--:;-Palmyra Atoll 

'-.I 

,-.)......Jarvis Island 

l \ ........ 

~ ;l;w-- American 

(:_ ....,} Samoa 

150'W 120' 90' 60' 

FIGURE !.-Exclusive Economic Zone (EEZ) of the United States, Commonwealth of Puerto Rico, Commonwealth of the Northern 

Mariana Islands, and United States overseas territories and possessions (outlines of map are approximate). Acreage now 

deemed within the U.S. EEZ includes: United States proper, 2.787 billion acres; Commonwealth of Northern Mariana Islands, 

0.299 billion acres; territories and possessions, 0.839 billion acres. 

The March lOth announcement did not specifically designate the geographic coordinates of the 

outer extent of the EEZ, but a general indication 

of its extent is the U.S. fisheries conservation 

zone, since the operational language of the EEZ 

proclamation generally follows the language of the 

Fisheries Conservation and Management Act. The 

limits of the fisheries zone were set forth in the 

Federal Register on March 7, 1977, and successive 

notices issued in 1977, 1978, and 1979 have corrected errors and made modifications to the original notice. An official depiction of these boundaries 

can be found on the National Ocean Survey's 

marine boundary charts and maps listed in the N ationa! Oceanic and Atmospheric Administrations's 

Map and Chart Catalogue 5. 

Also relevant in the definition of the EEZ 

outer limit is the fact that in some places the natural geologic prolongation of an undersea land mass 

can be more than 200 nautical miles from the 

shoreline. Article 76 of the UNCLOS treaty (Appendix C) addressed this issue, and the merits of 

this article have been widely discussed (see Hed2 

berg 1979, 1983; McKelvey, 1983). In any event, 

the EEZ is a vast new frontier to study and understand. It also is an immense region with potential 

resources of possibly economic importance. 

GEOLOGY 

Geologic features and processes, as we study 

them, do not stop at the ocean's edge, but extend 

offshore into the area known as the continental 

margin, which constitutes much of the EEZ. For 

the U.S. this margin area includes the edge of the 

North American continent as it extends out under 

the Atlantic, Pacific, and Arctic Oceans, the Gulf 

of Mexico, and the Caribbean and Bering Seas and 

is very diverse in its geologic history. Geologists 

have been conducting studi~s here because it affords an opportunity to learn more about the processes and forces responsible for shaping our continent and controlling the distribution of resources. 

The continental margin can be divided into a 

series of provinces called the continental shelf, continental slope, and continental rise, which occur in 

progressively deeper water (fig. 3). As the water 
FIGURE 2.-Schematic diagram showing the location of the baseline, territorial sea, contiguous zone, and EEZ with respect to the 

coastline. 

depth increases, the complexity of studying each 

province-and developing its resources-also increases. A brief discussion of the geologic history 

of the North American continent, and its place on 

the Earth's surface, will provide an example of 

how continental margins are formed. 

The Earth's crust is made up of gigantic plates 

of continental crust and oceanic crust. Most continental plates extend far out under the covering 

ocean and eventually meet a neighboring plate of 

oceanic crust or (in areas of narrow seas) an adjacent continental plate. According to the widely ac3 

cepted plate-tectonic theory, crustal plates are in 

motion relative to each other; from time to time 

over hundreds of millions of years they are broken 

along rift zones, and the huge fragments then 

spread away from the rift as though borne on conveyor belts in the underlying Earth's mantle. As 

each fragment moves, its leading edge may collide 

with another plate. Depending on the kinds of 

plates and the nature of their collision, this process 

may result in the building of a mountain range 

(such as the Rocky Mountains) or an oceanic island 

arc (such as the Mariana Islands or Aleutian Is-
CONTINENTAL 

~ II 

MARGIN 

ATLANTIC: 

(trailing edge) 

sea level 

YSSAL 

PLAIN 

;:~'!li~it~~~i)[lt~1!1~;it1't~~~~-·-·R· ~~~~~:z~=;~~~====~~~~~r-~~~v~ NORTH PACIFIC MARGIN· 

(collision) 

SOUTHERN CALIFORNIA 

BORDERLAND: 

(extentional) 

SOUTH PACIFIC: 

(volcanic arcs 

trenches, and 

carbonate reefs) 

FIGURE 3.-Idealized physiography of a continental margin and some common margin types. 

4 
lands), or a fault zone (such as the San Andreas). 

The collision, or subduction, zones as well as the 

rift zones are sites of volcanism and seismicity. In 

this process of plate collision, rocks formed in the 

oceans, even whole marine basins, can be emplaced 

onto continents, where erosion may later expose 

them so that they may be studied. Also in this process, broad reaches of continental crust can subside and be invaded by the sea; subsequent uplift 

then presents to geologists the resulting record of 

marine deposition and erosion over that part of the 

continental plate. Similarly, mineral deposits that 

form on the ocean floor and petroleum deposits 

within marine sedimentary basins may end up on 

the dry land of a continent. 

Two hundred million years ago the supercontinent called Pangea, composed of North and South 

America, Africa, and Europe, began to break up, 

with North America moving to the west-northwest. As North America moves on the Earth's surface, the Pacific coast-the leading edge-overrides the sea floor of the Pacific Ocean. Because 

this continental-oceanic plate interaction involves 

plate collision, characterized by tectonic and volcanic activity, the Pacific coast of North America is 

termed an active continental margin. The Atlantic 

coast is the trailing edge and is called a passive 

margin. 

Although the ocean severely limits the observations a geologist can make of the seabed, it does 

provide an excellent laboratory for studying ancient as well as modern marine sedimentary or 

mineral deposits. In addition, observations of active processes of marine deposition and erosion can 

be directly applicable in understanding our onshore geologic surroundings, and in the search for 

resources. Conversely, studies of former marine 

settings, now on land, together with offshore 

geophysical data and drillhole or surface samples, 

can provide an understanding of today's sea floor 

geology-the setting and makeup of the continental shelves, slopes, and rises, as well as the deep 

ocean floor. It is these studies that have already 

led to a vastly improved understanding of the processes shaping the Earth and moreover to the discovery of significant resources. 

RESOURCE POTENTIAL OF THE EEZ 

Major deposits of oil and gas and potentially 

important deposits of minerals, including strategic 

commodities, occur in the EEZ. However, because 

of its extreme size, resource estimates are based 

5 

on spotty data coverage requiring extrapolation of 

findings into unsurveyed and unsampled areas. 

Future exploration, technological developments, 

and economic conditions will determine which of 

these resources will be developable and when. 

Here, we present a general assessment of the hydrocarbon and mineral potential of the EEZ, as far 

as present understanding of the environments and 

processes will allow, and outline· techniques for improving this preliminary appraisal. 

OIL AND GAS RESOURCES 

Of offshore resources worldwide, oil and gas 

are the most extensively developed; accordingly, 

more reliable estimates of their abundance are 

available than for any other resources in the EEZ. 

The appraisal by Dolton and others (1981) of conventionally producible crude oil and natural gas on 

a portion of the U.S. outer continental shelf was 

used as the basis for our discussion of U.S. estimates. We use the commonly accepted terminology which defines "reserves" as proved and 

economically recoverable accumulations and "resources" as both reserves and undiscovered potential resources based on geologic knowledge of an 

area (fig. 4). The estimates presented below for 

the four major U.S. offshore regions (figs. 5, 8) are 

for undiscovered recoverable resources and are 

given as statistical mean values determined from 

data of Dolton and others (1981). 

The major geologic factors related to hydrocarbon occurrence and exploration are: (1) an adequate thickness of sedimentary rocks; (2) source 

beds containing considerable dispersed organic 

matter; (3) a suitable environment for the maturation of organic matter; ( 4) porous and permeable 

reservoir beds; (5) hydrodynamic conditions favorable for both early migration and ultimate entrapment of oil and gas; (6) a favorable thermal history; 

(7) adequate trapping mechanisms; and (8) suitable 

timing of hydrocarbon generation and migration in 

relation to the development of traps. Many other 

features can indicate favorability, for example, the 

presence of oil and gas seeps, a varied sequence of 

rock types, some organically rich marine sediments as source beds for the generation of oil and 

associated gas, nonmarine organically rich sediments for genesis of nonassociated gas, structural 

features that show progressive growth through 

geologic time, unconformities, and the presence of 

evaporite deposits. 
IDENTIFIED RESOURCES 

Demonstrated 

Inferred 

Measured Indicated 

ECONOMIC Reserves Inferred Reserves 

t-------11-----L---

MARGINALLY 

ECONOMIC 

t-------tt----------------

SUBECONOMIC 

UNDISCOVERED RESOURCES 

u 

~ 

0 

z 

0 

u 

UJ 

(!) 

z 

en 

<{ 

UJ 

0:: 

u 

z 

> 

1-

..J 

IIl 

en 

<{ 

UJ 

u.. 

INCREASING GEOLOGIC ASSURANCE------------

FIGURE 4.-0il and gas resources classification. (Modified from U.S. Bureau of Mines and U.S. Geological Survey, 1980.) 

5IZIN 

14IZIW 

4IZIN 

3IZIN 

13IZIW 

2IZIN 

14/W 

JUAN DE FVCAGORDA . 

SUBMARIM.E · "'I 

131!lW 12IZIW 

120W 11IZIW 

The Un1ted States has not resolved most of 1ts Contmental Shelf and 

Exclusive EconomiC Zone boundanes w1th other states. The llnft'j on this 

map are only approx•mate, and they do not necessanly reflect the pos1t1ons 

01 v.ews of the United States With respect to those boundanes 

1 !IZIW lOOW 

liZIIZIW 

500 

400 

90W SIZIW 7IZIW 

90W SIZIW 

1000 MILES 

800 KILOMETERS 

6IZIW 

SOUTHEAST 

ATLANTIC 

SEDIMENTARY 

BASINS 

70W 

5IZIW 

5IZIN 

5IZIW 

4IZIN 

3IZIN 

6IZIW 

2IZIN 

200 nautteal m11e ltm1t data based on NOS F1shenes 

Conservatton and Management Zone delmeat•on 

FIGURE 5.-Location of basins with oil and gas potential within the EEZ. Dashed lines indicate the boundary location discussed 

in Appendix C. 

6 
JURASSIC I CRETACEOUS REEF TREND 

ATLANTIC OCEAN 

\ 

J 

FIGURE 6.-Location of the offshore buried reef trend and various basins (patterned areas) (see fig. 5) formed following the split 

of North America from Africa. Solid line indicates carbonate buildup or well-developed reef; dashed line indicates carbonate 

bank. (From Schlee and Grow, 1980.) 

ATLANTIC REGION 

After Pangea broke up and North America 

began drifting northwest, the Atlantic Ocean 

started to form. In its early days, the Atlantic 

must have been a narrow, shallow, highly saline 

sea, with much evaporation; these features are recorded by numerous layers of salt along the continental margin. Salt was also being deposited in the 

Gulf of Mexico at this time. As the Atlantic widened, sediments pouring in were deposited on top of 

the salt, which in places flowed plastically due to 

the weight of the sediments and intruded upward 

into the overlying sediment layers as fingerlike 

masses called diapirs. In areas where conditions 

were right for oil and gas formation, hydrocarbons 

often accumulated in structural traps around such 

diapirs. As the ocean continued to widen, oceanographic conditions became favorable for the development of a major reef system which can be 

traced, through the use of seismic reflection equipment, for hundreds of miles from the Gulf coast 

around Florida and along the Atlantic coast (fig. 

6). Between this reef and the coast were deposited 

sediments carried by rivers, filling in a series of 

basins which formed as North America split away 

from Africa (fig. 7). Today rocks sampled in deep 

oil-test wells drilled on the continental shelf show 

a succession of deep-water deposits, due to the 

many times sea level has risen and fallen during 

the evolution of the margin. 

7 

The Atlantic region includes a series of basins-Georges Bank Basin, Baltimore Canyon 

Trough, several southeast Atlantic sedimentary 

basins, and the Blake Plateau Basin (fig. 5}--which 

are filled with sediments and sedimentary rocks 

0:::0 Rift stage basement of present basins 

~ Oceon1c basement 

- Bloke spur magnetic anomaly 

- MaJOr fracture zones 

FIGURE 7.-Configuration of basins mentioned in text that 

formed during the split of North America from Africa, 165 

m.y. ago. (From Dillon, 1983.) 
sometimes reaching a thickness of 43,000 feet. In 

addition, the continental slope and rise are underlain by a great wedge of sediments. The deep basins and the continental rise are all targets for petroleum exploration. Another potential resource is 

the offshore buried reef (fig. 6), noted in the previous paragraph; depending on the porosity of the 

reef rock and the thermal history of the nearby 

slope and shelf, this ancient reef might serve as a 

hydrocarbon reservoir. Because of the depth of 

water in which they are located, these areas are 

just beginning to be evaluated for their resource 

potential. 

Much detailed marine geophysical work and 

rock coring from deep wells remain to be done to 

show what the Atlantic region's hydrocarbon potential really is. However, oil and gas resources 

have been estimated for Georges Bank, the Baltimore Canyon Trough, and three sedimentary basins in the southeast Atlantic. The total estimate 

as of 1981 is 5.4 billion barrels (bbl) of oil and 23.5 

trillion cubic feet (tcf) of gas. 

GUlF OF MEXICO REGION 

As for the Atlantic region, the early history of 

the Gulf of Mexico region was characterized by the 

deposition of a thick low-density salt layer. Later, 

the Mississippi River flowing into the Gulf deposited a thick accumulation of sediment, eroded from 

the central United States. This accumulation has 

built a large delta, the weight of which on top of 

the salt has resulted in extensive plastic flow of the 

salt upward into the sediments to form diapirs as 

well as deforming the sediments and shaping the 

morphology of the sea floor into ridges, troughs, 

and hills. The Gulf is bounded on the east and 

south by the large carbonate platforms of Florida 

and the Yucatan Peninsula, which were constructed by marine organisms; in fact coral reefs 

can be found growing today on the tops of ridges or 

hills underlain by salt diapirs in the shallow waters. Over millions of years, abundant organic material generated by these marine organisms in the 

warm, nutrient-rich water and a high rate of 

sedimentation have served to provide conditions 

favorable for the generation of oil and gas, and it 

is the vertical walls of the diapirs that provide 

numerous structural traps in which the oil and gas 

can accumulate. 

The Mississippi River, its delta, and deepwater fan afford geologists a view of a modern active river delta system and its associated hydrocar8 

bon reservoirs. On land in buried basins, oil and 

gas are often found in ancient river deltas and 

fans. Therefore, by studying the dynamic processes active today in the Mississippi River system, 

scientists can understand and more efficiently 

exploit both modern and ancient delta and fan reservoirs. 

The Gulf of Mexico shelf area has been extensively and successfully developed; however, the 

area more than 200 meters deep has not. This 

deeper area has been separated into eastern and 

western slope zones for the purpose of resource assessment (fig. 5). Study of the eastern zone 

suggests that there is little potential for oil and gas 

reserves as indicated by resource estimates of 0.2 

bbl of oil and 0.5 tcf of gas. The western zone is 

much more favorable, containing a complex pattern of salt intrusions and thick sediments; resource estimates for that area are 2. 4 bbl oil and 

26.1 tcf gas. No resource estimates are available 

for the deep abyssal plain within the EEZ, but it 

is also covered with thick sediments containing 

large structures capable of trapping large amounts 

of oil and gas. 

PACIFIC REGION 

The Pacific region constitutes the leading edge 

of the North American continent and is an active 

margin in which the continental plate of North 

America is in collision with the sea-floor plate of 

the Pacific Ocean. This active margin has, as most 

all generally have, a much narrower continental 

shelf, slope, and rise than a passive margin. Flanking the narrow margin to seaward is a broad continental borderland composed of numerous islands, 

banks, and basins, some of the basins which are 

over 6,000 feet deep, where sediments transported 

by ocean currents or eroded from surrounding 

ridges have accumulated (fig. 3). Several basins 

close to the coast contain old deep-water fan deposits and have proven oil reservoirs, such as 

those in the Santa Barbara Channel. 

The Pacific region has been split into three 

areas for purposes of resource assessment: the 

southern California borderland, the northern and 

central California margins, and the OregonWashington basins (fig. 5). No assessment of oil 

and gas potential has been made by the U.S. 

Geological Survey seaward of the 2,500-meter 

depths of the slope, though the possibility for 

economically exploitable hydrocarbon deposits may 

exist in the area of the enormous Monterey deep-
70 

60 

50 

sea fan off central California (Wilde and others, 

1976) (fig. 5). The resource estimates for the Santa 

Barbara Channel are 1.3 bbl of oil and 2.5 tcf gas; 

for the more southerly borderland basins the estimates are 1.1 bbl and 1.4 tcf, for a total of 2.4 bbl 

of oil and 3. 9 tcf of gas. The northern and central 

California margins have been subject to large-scale 

faulting which formed a series of five sedimentfilled basins. Test wells have generally had negative results in the basins, despite promising source 

rocks and structures. Total resource estimates are 

1.0 bbl of oil in three basins, with individual basins 

containing from 0.1 to 0. 7 bbl; gas estimates are 

1. 7 and 0.2 tcf in only two of the basins. The Oregon-Washington basins represent a single, large 

sedimentary trough separated into structural basins; however, there appear to be few rocks with 

:40 

BATHYMETRY (200 AND 2 500m) 

=0 200 NAUTICAL MILE LIMIT 

AREA S OF POTENTIAL AND 

PROVEN HYDROCARBONS 

c:::::::c, 

USSR 

organic deposits, and moreover the thermal history is believed to be unfavorable for hydrocarbon 

development. The area resource estimates are 0.3 

bbl of oil and 1.5 tcf of gas. 

ALASKA REGION 

The Alaska region is an enormous area comprising diverse geologic elements. Whereas southern Alaska is a complex of small connected plates 

that extend offshore into the Gulf of Alaska (fig. 

8), the Aleutian Islands represent a full-fledged active margin forming a volcanic arc which is flanked 

on the seaward side by a deep basin, or trench. 

Along this trench, the sea floor of the Pacific 

Ocean is being pushed down, or subducted, under 

the continental margin; over 5,000 linear miles of 

ocean crust have been consumed along this trench. 

140 120 100 

... _ .......... , 

\ 

I 

I 

I 

I 

ALASKA 

60 

50 

-. ~~====~50~0~====g;ID•OO miles 

180 

The Un•ted States has not resolved most of •t s Cant mental Shelf and 

bclus•ve Econom•c Zone boundanes with other states. The tines on th•s 

map are only approJumate, and they do not necessan ly reflect the pos•tlons 

or v1ews of the Un•ted States w1th respect to those boundanes 

! 60E 

La mbert Equal Area Pro je cti on 

140 

200 naut1ca! m1le l•m•t data based on NOS F1sher1es 

ConservatiOn and Management Zone delmeat •on 

FIGURE 8.-Location of basins with oil and gas potential within the EEZ. Dashed line indicates the boundary location discussed 

in Appendix C. 

9 
As this crust is pushed down deep within the 

Earth, it melts and then rises to form the volcanic 

rocks of the Aleutian Islands. Minerals originally 

deposited within the rocks of the sea floor are also 

subducted beneath and redeposited within the 

Aleutian arc. Geologists are particularly interested 

in island-arc regions because they include deep 

sedimentary basins, which if conditions are right, 

can contain oil and gas. In front of the arc, between the arc and the trench, is the forearc basin, 

where compressional forces can deform the sediments eroded from land, erupted by volcanoes, or 

composed of organisms settling out of the water 

column and deposited in the basin. Cook Inlet and 

several other basins located near shore in this 

forearc region are being evaluated for their hydrocarbon potential. Behind the arc are backarc basins, formed by tensional forces caused by the 

downgoing sea-floor slab, that, if conditions are 

right, may contain hydrocarbon deposits. 

The northern coast of the Alaska region is a 

passive type margin with thick accumulations of 

sediments, diapirs, and other features similar to 

the Atlantic margin. The giant oil field onshore at 

Prudhoe Bay suggests that the continental margin, 

under the shelf, slope, and rise, also may have important hydrocarbon reserves. 

The vastness of the region and the hostile 

climatic conditions make exploration for resources 

difficult. When resources are found, the winter 

storms and ice make it difficult to build permanent 

recovery stations. In some areas, ice extends all 

the way down to the sea floor in the waters overlying the shelf, and so ice movement leaves large 

gouges in the sediment. Under these conditions, 

drilling for oil or production itself are extremely 

difficult. For the sake of brevity, the Alaskan region is divided into three sections (fig. 8), despite 

inhomogeneities, and described only briefly: (1) the 

Gulf of Alaska area, south of the Aleutians, (2) the 

Bering Sea area between the Aleutians and the 

Bering Strait, and (3) the area north of the Bering 

Strait. 

South of the Aleutians the resource estimates 

are as follows: 

Gulf of Alaska-----------

Kodiak Basin ------------

Lower Cook Inlet------

Total -----------------

Oil (bbl) 

0.4 

.4 

.4 

1.2 

Gas (tcf) 

2.2 

2.0 

2.4 

6.4 

The thermal and structural history of these three 

basins suggests that gas rather than oil was generated. The western Gulf of Alaska area has thick 

sediments (up to 5 km) and abundant structures 

capable of containing hydrocarbons, but drilling results have been poor, apparently due to lack of 

suitable reservoir rocks. The same is true for the 

Cook Inlet area. The eastern Gulf of Alaska area is 

most promising, with excellent source rocks and 

fair trap potential, though the reservoir potential 

is questionable. 

Resource estimates for Bering Sea and environs are as follows: 

Bristol Bay Basin -----

St. George Basin -------

N avarin Basin-----------

Norton Basin ------------

Total -----------------

Oil(bbl) 

0.2 

.4 

.9 

.2 

1.7 

Gas (tcf) 

1.0 

2.3 

5.6 

1.2 

10.1 

The basins in the Bering Sea area vary widely in 

geologic origin. Bristol Bay Basin is a single, broad 

structural depression with a sediment thickness as 

much as 7 km; St. George Basin is a 10-km deep, 

sediment-filled, fault-bounded basin; Navarin 

Basin is actually three elongate basins with a sediment thickness of as much as 15 km; and Norton 

Basin is broken by faults into sections with sediment thicknesses as much as 7 km. Only Bristol 

Bay has been drilled, showing some oil and gas in 

its southern reaches. Resource potential estimates 

for the other basins are based on seismic information and surface sampling. 

For the area north of Bering Strait, the resource estimates are as follows: 

Hope Basin---------------

Chukchi Basin-----------

Beaufort Basin ----------

Total -----------------

Oil(bbl) 

Negligible 

1.4 

7.8 

9.2 

Gas (tcf) 

0.3 

6.4 

39.3 

46.0 

The Hope Basin has a sediment thickness of only 3 

km, barely enough for hydrocarbon generation. 

The Chukchi Basin is more than twice as thick and 

has structural features providing potential hydrocarbon traps. By far the most promising basin of 

the three for hydrocarbon production, is the 

Beaufort Basin, where the onshore producing oil 

fields are within 10 km of the coastline; here, petroliferous onshore deposits are thought to extend 

offshore, and sediments at least 6 km thick occur 

10 
all the way to the edge of the broad shelf. It is critical to point out that the continental shelf in the vicinity of the Chukchi and Beaufort Seas extends 

well beyond 200 nautical miles from shore (fig. 8). 

Thus if the "natural prolongation" criterion discussed in the section "Description and History of 

the EEZ" is applied, this extended portion could 

fall within U.S. jurisdiction. 

ISLAND REGIONS 

Besides the U.S. part of the North American 

continent, the EEZ also includes waters and subsea lands adjacent to Puerto Rico and the Virgin 

Islands in the Caribbean Sea, and the Hawaiian Islands, Northern Mariana Islands, and numerous 

other islands in the Pacific Ocean. Puerto Rico, the 

Virgin Islands, and the Northern Mariana Islands, 

like the Aleutian Islands, are parts of island arcs. 

The potential for oil and gas resources within 

the EEZ of the U.S. Pacific possessions has not 

yet been evaluated. Most island areas were not 

until recently believed to have any potential for 

hydrocarbon resources. However, the facts and 

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models relating to the geologic history of this region are changing rapidly as a result of U.S. 

Geological Survey-United Nations hydrocarbon resource studies in the southwest Pacific (Greene 

and Wong, 1983) (fig. 9). Current information indicates that the most promising area for oil and gas 

is the region west of Guam and the Marianas, 

which should be surveyed geophysically to locate 

sedimentary basins. 

HARD-MINERAL RESOURCES 

Nearly all known hard-mineral resources of 

the U.S. continental margin are located on the continental shelf (fig. 10), owing, in part, simply to the 

paucity of information on the deeper, slope regions. Until recent plans for leasing polymetallic 

sulfides in the Gorda Ridge area (figs. 5, 11) were 

announced, no hard-minerals leasing in Federal 

waters had occurred since 1968. The lifting of this 

defacto moratorium is expected to encourage the 

exploration for hard minerals. 

Near-shore shelf resources usually include 

sand and gravel, salt, phosphorite, and placer deAREA OF U.S.G.S.-UNITED NATIONS 

RESOURCE EVALUATION EXPEDITION 

TO THE SOUTHWEST PACIFIC 

FIGURE 9.-Ship tracklines from U.S. Geological Survey-United Nations hydrocarbon resource study (Greene and Wong, 1983). 

11 
FIGURE 10.-Hard-mineral resources contained within the U.S. EEZ include manganese, phosphorite, gold, platinum, and titanium. 

Many of these minerals are found in sand and gravel deposits on the continental shelf. (From Manheim and Hess, 1981.) 

posits (Manheim and Hess, 1981). Sand and gravel 

deposits are reasonably well known and have attracted commercial interest where dictated by 

local need. Salt deposits of the Gulf of Mexico may 

contain evaporite minerals enriched in potassium, 

bromine, or other economic commodities. Phosphorite, necessary for agriculture, is known to be 

present off southern California and the southeast 

Atlantic margin. Other surveys have revealed the 

presence of phosphorite and of pavement-like deposits and nodules of manganese covering the 

Blake Plateau, off the Carolina coast (fig. 10). 

Glaciers and rivers disgorge large quantities 

of sediments onto the continental shelf, including 

minerals of economic interest. Ocean currents and 

storm-driven currents rework these sediments, 

often concentrating mineral deposits as placers, of 

titanium, platinum, rare-earth elements, and gold. 

Several such deposits are known offshore of 

12 

Alaska, California, Oregon, and Washington, and 

others are likely buried within the continental margin. 

Development of salt and evaporite, phosphorite, and placer deposits is presently not economically feasible, but advanced technologies and increases in prices might make them profitable. 

These deposits, therefore, warrant study. The two 

other possibly economic hard-mineral resources located farther offshore but still within the EEZ are 

polymetallic sulfides and cobalt-rich manganese 

crusts. 

POlYMETAlliC SUlFIDES 

Spreading oceanic rift zones are sites where 

molten rock rises from the Earth's interior and is 

injected along the axis of the rift (fig. 11). The rock 

then cools and creates new sea floor. Sea water is 

believed to percolate deep into cracks near the rift 
DE FUCA PLATE 

PACIFIC PLATE 

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spreading 

~ allic sulfides 

I 

I 

J 

I 

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"\ 

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FIGURE 11.-Polymetallic sulfide deposits form at vents along the axis of a spreading ridge (see 

text for explanation). 

13 
FIGURE 12.-A sample of a polymetallic sulfide deposit from a hydrothermal vent. 

and react with the rocks of the ridge to form mineral-rich hydrothermal solutions that rise to the 

sea floor, where minerals precipitate as sulfiderich deposits. They take on a variety of forms, including flows, columnar edifices around vents, encrustations on slopes, and small cones built on sediment (figs. 12, 13). The deposits are relatively rich 

in zinc, iron, and copper, with lesser quantities of 

silver, cadmium, molybdenum, lead, vanadium, 

chromium, barium, strontium, gold, and platinum. 

Deposits of polymetallic sulfides were first 

discovered in the axis of the East Pacific Rise at 

21°N. latitude in 1978 (Francheteau and others, 

1979). They have since been found along the rift 

zones and spreading centers, as well as in the axis, 

of the Juan de Fuca Ridge, off the coast of 

Washington (figs. 5, 11); this ridge is partly within 

the U.S. EEZ but also extends northward into 

waters off Canada. Another active spreading center nearby and closer to shore is the Gorda Ridge, 

also judged to be a possible location for sulfide de14 

posits. Because spreading-center deposits are considered to be modern counterparts of on-land copper-iron-zinc sulfide ores, they have been compared with the southwest U.S. land-based deposits, which suggests that the thickness, continuity, and grade of ore is probably not uniform 

within, and between, spreading centers. Ore-deposit thicknesses of up to 40 m occur on land, but 

currently no subsurface coring has been done to assess the thickness of marine mineral deposits. A 

joint U.S.-Canadian program was scheduled to 

drill shallow cores in the Juan de Fuca area in September 1983. This program of surveying, sampling, and analysis of the U.S. Geological Survey 

was to determine the resource potential of 

polymetallic sulfide deposits at this ocean ridge. 

Core, surface, and fluid samples, as well as suspended-sediment samples downcurrent from 

vents, are expected to be collected in a grid large 

enough to show spatial variability. 

Not all the islands in the Pacific are at the 
FIGURE 13.-Polymetallic sulfide deposit with a columnar shape. 

edge of a plate capping an island arc. Some, like 

the Hawaiian and Midway Islands, occur within 

the Pacific plate. They form over what geologists 

call hot spots, places where plumes of molten rock 

are rising from deep within the Earth. These 

plumes are fixed in location, and as the crustal 

plate of the Pacific moves over them, a line of volcanoes or seamounts-volcanoes that do not reach 

above the sea surface--is formed. The island of 

Hawaii today is over a hot spot which is causing 

volcanic activity. The trend of the chain of islands 

from Midway to Hawaii shows the northwesterly 

direction that the Pacific plate is moving. Each island was originally over the hot spot where Hawaii 

is today. Although no deep basins filled with sediment are associated with this type of island, minerals accumulating on the volcanic edifice may be important. Polymetallic sulfides may be deposited at, 

or just beneath, the sea floor in the vicinity of the 

hot spot where volcanic activity is occurring. 

Geologists have only just begun to study the 

15 

geology and resources of these hot spot islands. 

The underwater flanks of the volcanoes are relatively steep and the water is over 12,000 feet deep 

in places, which makes their study difficult. The 

very basic question of their particular types of resources and distribution still needs to be answered. 

COBALT-RICH MANGANESE CRUSTS AND NODULES 

Recent work by the U.S. Geological Survey 

suggests that cobalt-rich manganese crusts on 

the flanks of seamounts and oceanic islands in 

the central Pacific could represent a significant 

mineral resource. The crusts appear to average 2 

em in thickness and are fairly uniformly distributed at depths of 1,000-2,600 m (Geotimes, 1982). 

They are known to be present on many of the islands which are U.S. territories and possessions in 

the Pacific, and there are over 200 such islands and 

seamounts within the U.S. EEZ boundaries in the 

Pacific. 
The crusts generally contain 1. 0 percent or 

more cobalt, 0.5 percent nickel, and 15-25 percent 

manganese. Though the concentrations vary, they 

may represent an economic resource. Crusts at 

depths shallower and deeper than 1,000-2,500 m 

are generally not as rich in cobalt. Deep-sea manganese nodules, believed to be forming by processes similar to those which produce the crusts, have 

a mean cobalt content for high-grade samples in 

the Pacific of 0.27 percent (McKelvey and others, 

1983). The crusts thus apparently contain significantly more cobalt than the nodules, which have received so much attention in recent years. However, preliminary analysis of a sample collected on 

the top of Horizon Guyot, a seamount southeast of 

Hawaii, yielded a cobalt content of 0. 74 percent. 

As a result the economic potential of shallow-water 

nodules is being reevaluated. If the seamounts 

prove to be covered with the crusts or nodules, a 

single seamount could yield enough ore for a commercial mining operation. The importance of this is 

highlighted by the fact that the U.S. has no domestic sources of cobalt, depending largely on Mrica 

for its supplies of this strategic mineral. 

EXPLORATION METHODS 

The resource assessments in this report are 

tentative, for they are based, in most cases, on extrapolation of the data available from uneven geographical coverage of the vast area of the EEZ. 

Conclusions, especially for the cobalt crusts and 

nodules and the polymetallic sulfides, have been 

drawn without a complete understanding of the 

spatial extent of the resources or variability in 

composition. 

A variety of geophysical and sampling techniques is available for identifying resources and assessing their potential in the EEZ. Some employ 

traditional seismic reflection and sampling equipment; their capabilities and limitations for resource 

assessment are well documented and thus are only 

briefly mentioned here. Newer techniques, for 

mapping broad swaths of the sea floor, are especially well suited to surveys of the large areas of 

the EEZ, and three such systems are described 

here. 

SEISMIC REFLECTION 

Seismic reflection techniques are useful for 

identifying the physiography of the sea floor and 

the character of the underlying strata (fig. 14). In16 

terpretation of such seismic records is the basic 

source for regional assessment of oil and gas resources. For resources which are surficial, seismic 

reflection techniques are less useful, since no idea 

of the lateral extent of a feature can be extracted 

without a lengthy survey. The combination of seismic profiling with a swath-mapping system, as 

those mentioned below, dramatically increases the 

information value of an oceanographic trackline. 

LONG RANGE SIDE-SCAN SONAR (GLORIA) 

Side-scan sonar is a process in which a swath 

of the sea floor is ensonified with acoustic signals; 

variations in the topography of the ocean floor 

alter the energy in the signal bounced back to the 

receiver, and these irregularities are used to produce an acoustic picture of the ocean floor. The signals are sensitive to changes in shape as well as 

bottom composition, and thus side-scan systems 

are able to map bedforms in addition to such deposits as sand and gravel deposits on the continental shelf. With the development of the GLORIA 

(Geological Long Range Inclined Asdic) system in 

1970, this technique became available for the deep 

ocean as well (fig. 15). 

The GLORIA system consists of a 2-ton, 8-m 

long transducer towed 50 m below the sea surface 

at speeds of up to 10 knots. The swath width can 

be set at 14, 30, or 60 km, and resolution of features on the scale of tens of meters is possible. The 

record produced by the newest systems is digitally 

recorded on magnetic tape and can be processed to 

account for variation in the ship's speed and corrected for the slant range distance to the sea floor. 

Additional corrections account for water-density 

variation, particularly those due to the thermal 

structure of the water column. 

The GLORIA system is particularly useful for 

reconnaissance of frontier regions, for it can determine the orientation and extent of large linear features such as ridges, bedforms, and channels. In a 

survey of the continental slope off the mid-Atlantic 

states, for example, canyons 20 km long cutting 

across the slope can be traced on the GLORIA 

sonographs, and tributaries as closely spaced as a 

few hundred meters can be also distinguished (fig. 

16). In this case, and others, GLORIA has made 

clear for the first time the intricate patterns of 

meandering gullies and channels of oceanic canyon 

and fan systems (Twichell and Roberts, 1982; 

Damuth and others, 1983). 
SEDIMENT FILLED BASIN 

_j 

w 

> 

<! 

0::: 

f-

>-

<! 

5: 

I 

N 

u 

w 

(f) 

FIGURE 14.---Seismic profile across the Blake Escarpment showing the continental margin with a reef and stratified sediments 

abutting the escarpment (Dillon and others, 1979). 

WIDE-ANGLE MULTIBEAM ECHO SOUNDING (SEABEAM) 

The Seabeam wide-angle multibeam profiling 

system produces a bathymetric map in real time 

from a swath of the ocean floor beneath a ship's 

track. The contoured strip covers a 43° arc beneath 

the ship so that the width of coverage varies from 

about 150 m on the outer shelf to 4 km in the deep 

ocean. The contour interval can be set as low as 2 

m. The hull-mounted transducer system is presently available, or in the process of installation, 

on three U.S. university ships, on Surveyor (operated by the National Oceanic and Atmospheric Administration), and on several French and German 

research vessels. 

The Seabeam system can be used simultaneously with seismic reflection equipment, so that 

the lateral extent of a surface feature can be related to its vertical structure. This combination is 

valuable for delineating the surface expression and 

17 

lithologic character of structural traps for hydrocarbons, such as salt domes and diapirs. 

One of the resident ships for the Seabeam system is the Atlantis II, of the Woods Hole Oceanographic Institution; it also is the mother ship for the 

deep-sea research submersible vehicle Alvin. With 

this dual operation, the exact nature of bottom features can be observed and sampled from Alvin at 

the same time their extent is being mapped by the 

Atlantis II. This type of survey will be especially 

valuable for identifying and assessing surface res_gurces such as cobalt crusts. 

MIDRANGE SIDE-SCAN SONAR (SEA MARC) 

The Sea MARC I* side-scan sonar, was 

developed for Lamont-Doherty Geological Observatory, records, like GLORIA, differences in 

acoustic reflectivity of the sea floor. Unlike 

• Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. 
GUllY , 

SONAR 

FISH SONOGRAPH 

-

' " ECHO 

SOUNDING 

FIGURE 15.--Schematic diagram of GLORIA side-scan sonar process. 

GLORIA, it is towed 100-300 m above the bottom, 

avoiding the distortions introduced by the water 

column, particularly temperature variation. This 

system provides for greater resolution of sea-floor 

features than the GLORIA system but at a reduced swath width (compare figs. 16, 17). The 

swath width can be set at either 1 km or 5 km, 

with horizontal resolution in centimeters or meters, respectively. The former, for example, might 

distinguish nodule-sized features; the latter could 

trace the fronts oflava flows. 

A recent version, the Sea MARC II, operated 

by the Hawaii Institute of Geophysics, is towed 

higher in the water column than the Sea MARC I, 

allowing for higher speeds. A major innovation, 

one also available on later versions of the deeptowed Sea MARC I, is a bathymetry system with 

a theoretical resolution of 6 m for the entire 5-km 

swath (fig. 18), though this resolution has not yet 

been verified. Once verified this system will give 

clearer images of smaller scale features than 

GLORIA, providing the capability for even more 

useful geologic investigations. 

18 

The primary value of GLORIA, Seabeam, and 

Sea MARC is the detailed information obtainable 

over extended areas. The huge expanse of the 

EEZ, combined with the current minimal coverage 

in the nonshelf areas, makes this equipment important for initial surveys in order to determine regional geology. Follow-up multichannel seismic 

surveys will be necessary for locating deep basins 

which could serve as hydrocarbon traps, and sampling programs will be necessary for resource assessment, as well as the initial geologic mapping. 

CONCLUSION 

Although the EEZ has high potential for significant recoverable energy and mineral resources, 

further information is necessary before the extent 

of that potential can be reliably estimated. The 

values in this report are mostly hypothetical, 

based on the best available data. Moreover, they 

do not take into account the technical or economic 

feasibility of the mineral recovery. The exploration 

section is intended as an introduction to the equip-
Western 

flank of 

Lydonia 

Canyon 

uncharted 

canyon 

Gilbert 

Canyon 

Chebacco 

Canyon 

File bottom 

Canyon 

Eastern 

flank of 

Oceanographer -- Canyon 

downslope------ ------ 13 km ----

+ + 4'PliJ' 

40•HI' 

~-----------~--------L------~-------- ... ... FIGURE 16.---Stereopair sonographs and location map of the upper continental slope off Georges 

Bank showing a high density of canyons extending across the Atlantic slope (Teleki and 

others, 1981). 

19 
38"15' 

2-

1-

KM/Cl 

0 

CONTOUR INTERVAL · 

FIGURE 17.-Sea MARC I side-scan sonar data clearly showing canyon valleys incised in the continental slope. Photograph correlates with area I below. (From McGregor and others, 1982.) 

20 
FIGURE 18.-Sea MARC II operation system and mapping geometry. (From Blackington, 1983.) 

21 
ment and methods available for making relatively 

rapid, reasonably accurate assessments of geologic 

environments. This advancing technology is extending our scientific reach, so that surveys are increasingly improving our knowledge of the 

geologic processes and the presence and distribution of resources in the EEZ. 

REFERENCES 

Blackington, J. G., 1983, First results from a combination sidescan sonar and sea floor mapping system (Sea MARC II): 

Offshore Technology Conference, 15th, OTC 4478, p. 1-5. 

Damuth, J. E., Kolla, V., Flood, R. D., Kowsmann, R. 0., 

Monteiro, M. C., Gorini, M. A., Palma, J. J. C., and Belderson, R. H., 1983, Distributary channel wandering and 

bifurcation patterns on the Amazon deep-sea fan as revealed by long-range side scan sonar (GLORIA): Geology, 

v. 11, no. 2, p. 94-98. 

Dillon, W. P., 1983, Regional geology and petroleum potential, 

in Dillon, W. P., ed., Geology report for proposed oil and 

gas lease sale No. 90; continental margin off the southeastern United States: U.S. Geological Survey Open-File Report 83-186, p. 6-66. 

Dillon, W. P., Poag, C. W., Valentine, P. C., and Paull, C. K., 

1979, Structure, biostratigraphy, and seismic stratigraphy 

along a common-depth-point seismic profile through three 

drill sites on the continental margin off Jacksonville: U.S. 

Geological Survey Miscellaneous Field-Studies Map MF1090. 

Dolton, G. L., Carlson, K. H., Charpentier, R. R., Coury, A. 

B., Crovelli, R. A., Frezon, S. E., Khan, A. S., Lister, J. 

H., McMullin, R. H., Pike, R. S., Powers, R. B., Scott, E. 

W., and Varnes, K. L., 1981, Estimates of undiscovered 

recoverable conventional resources of oil and gas in the 

United States: U.S. Geological Survey Circular 860, 87 p. 

Francheteau, J., Needham, H. D., Choukroune, P., Juteau, T., 

Seguret, M., Ballard, R. D., Fox, P. J., Normark, W., 

Carranza, A., Cordoba, D., Guerrero, J., Rangin, C., 

Bougault, H., Cambon, 0., and Hekinian, R. 1979, Massive 

deep-sea sulfide ore deposits discovered on the East Pacific 

Rise: Nature, v. 227, p. 523-528. 

22 

Geotimes, 1982, Cobalt found in Pacific, Geotimes, v. 27, no. 12, 

p. 25-26. 

Greene, H. G., and Wong, F. L., 1983, Hydrocarbon resource 

studies in the southwest Pacific, 1982: U.S. Geological Survey Open-File Report 83-293. 

Hedberg, H. D., 1979, Ocean floor boundaries: Science, v. 204, 

p. 135-144. 

--1983, Letters and comments: A critique of boundary provisions in the Law of the Sea Treaty: Ocean Development 

and International Law Journal, v. 12, no. 3-4. 

Manheim, F. T., and Hess, H. D., 1981, Hard mineral resources around the U.S. continental margin: Offshore 

Technology Conference, 13th, OTC 4131, p. 129-138. 

McGregor, B. A., Stubblefield, W. L., Ryan, W. B. F., and 

Twichell, D. C., 1982, Wilmington submarine canyon: a 

marine fluvial-like system: Geology, v. 10, p. 27-30. 

McKelvey, V. E., 1983, Letter to the editor: Ocean Development and International Law Journal, v. 12, nos. 3-4, p. 

343-344. 

McKelvey, V. E., Wright, N. A., and Bowen, R. W., 1983, 

Analysis of the world distribution of metal-rich subsea 

manganese nodules: U.S. Geological Circular 886, 101 p. 

Schlee, J. S., and Grow, J. A., 1980, Buried carbonate shelf 

edge beneath the Atlantic continental slope: Oil and Gas 

Journal, v. 78, no. 8, p. 148-156. 

Teleki, P. G., Roberts, D. G., Chavez, P. S., Somers, M. L., 

and Twichell, D. C., 1981, Sonar survey of the U.S. Atlantic continental slope; acoustic char:lcteristics and image 

processing techniques: Offshore Technology Conference, 

13th, OTC 4017, p. 91-95. 

Twichell, D. C., and Roberts, D. G., 1982, Morphology, distribution, and development of submarine canyons on the 

United States Atlantic continental slope between Hudson 

and Baltimore Canyons: Geology, v. 10, p. 408-412. 

United States Bureau of Mines and the U.S. Geological Survey, 

1980, Principles of a resource/reserve classification for minerals: U.S. Geological Survey Circular 831, 5 p. 

United Nations Conference on the Law of the Sea, 1982, Convention on the Law of the Sea and resolutions I-IV: New 

York, 11th session, March-April1982, p. 38-39. 

Wilde, P., Normark, W. R., and Chase, T. E., 1976, Petroleum 

potential of continental rise off central California - summary, in Circum-Pacific Energy and Mineral Resources, 

American Association of Petroleum Geologists, Memoir No. 25, p. 313-317. 
APPENDIXE'S A-C 
APPENDIX A 

THE WHITE HOUSE 

Office of the Press Secretary 

Embargoed for release at 4:00 pm est March 10, 1983 

STATEMENT BY THE PRESIDENT 

The United States has long been a leader in developing customary and conventional law 

of the sea. Our objectives have consistently been to provide a legal order that will, among other 

things, facilitate peaceful, international uses of the oceans and provide for equitable and effective management and conservation of marine resources. The United States also recognizes that 

all nations have an interest in these issues. 

Last July I announced that the United States will not sign the United Nations Law of the 

Sea Convention that was opened for signature on December 10. We have taken this step because several major problems in the Convention's deep seabed mining provisions are contrary 

to the interests and principles of industrialized nations and would not help attain the aspirations 

of developing countries. 

The United States does not stand alone in those concerns. Some important allies and 

friends have not signed the Convention. Even some signatory States have raised concerns 

about these problems. 

However, the Convention also contains provisions with respect to traditional uses of the 

oceans which generally confirm existing maritime law and practice and fairly balance the interests of all States. 

Today I am announcing three decisions to promote and protect the oceans interests of the 

United States in a manner consistent with those fair and balanced results in the Convention and 

international law. 

First, the United States is prepared to accept and act in accordance with the balance of 

interests relating to traditional uses of the oceans-such as navigation and overflight. In this 

respect, the United States will recognize the rights of other States in the waters off their 

coasts, as reflected in the Convention, so long as the rights and freedoms of the United States 

and others under international law are recognized by such coastal States. 

24 
Second, the United States will exercise and assert its navigation and overflight rights and 

freedoms on a worldwide basis in a manner that is consistent with the balance of interests reflected in the Convention. The United States will not, however, acquiesce in unilateral acts of 

other States designed to restrict the rights and freedoms of the international community in 

navigation and overflight and other related high seas uses. 

Third, I am proclaiming today an Exclusive Economic Zone in which the United States will 

exercise sovereign rights in living and non-living resources within 200 nautical miles of its 

coast. rhl.s will provide United States jurisdiction for mineral resources out to 200 nautical 

miles that are not on the continental shelf. Recently discovered deposits there could be an important future source of strategic minerals. 

Within this Zone all nations will continue to enjoy the high seas rights and freedoms that 

are not resource-related, including the freedoms of navigation and overflight. My Proclamation 

does not change existing United States policies concerning the continental shelf, marine mammals and fisheries, including highly migratory species of tuna which are not subject to United 

States jurisdiction. The United States will continue efforts to achieve international agreements 

for the effective management of these species. The Proclamation also reinforces this government's policy of promoting the United States fishing industry. 

While international law provides for a right of jurisdiction over marine scientific research 

within such a zone, the Proclamation does not assert this right. I have elected not to do so because of the United States interest in encouraging marine scientific research and avoiding any 

unnecessary burdens. The United States will nevertheless recognize the right of other coastal 

States to exercise jurisdiction over marine scientific research within 200 nautical miles of their 

coasts, if that jurisdiction is exercised reasonably in a manner consistent with international law. 

The Exclusive Economic Zone established today will also enable the United States to take 

limited additional steps to protect the marine environment. In this connection, the United 

States will continue to work through the International Maritime Organization and other appropriate international organizations to develop uniform international measures for the protection 

of the marine environment while imposing no unreasonable burdens on commercial shipping. 

The policy decisions I am announcing today will not affect the application of existing 

United States law concerning the high seas or existing authorities or any United States government agency. 

In addition to the above policy steps, the United States will continue to work with other 

countries to develop a regime, free of unnecessary political and economic restraints, for mining 

deep seabed minerals beyond national jurisdiction. Deep seabed mining remains a lawful exercise of the freedom of the high seas open to all nations. The United States will continue to allow 

its firms to explore for and, when the market permits, exploit these resources. 

The Administration looks forward to working with the Congress on legislation to implement these new policies. 

25 
APPENDIX 8 

THE WHITE HOUSE 

Office of the Press Secretary 

Embargoed for releast at 4:00 pm est March 10, 1983 

UNITED STATES OCEANS POLICY FACT SHEET 

Today the President announced new guidelines for U.S. oceans policy and proclaimed an 

Exclusive Economic Zone (EEZ) for the United States. This follows his consideration of a 

senior interagency review of these matters. 

The EEZ Proclamation confirms U.S. sovereign rights and control over the living and nonliving natural resources of the seabed, subsoil and superjacent waters beyond the territorial sea 

but within 200 nautical miles of the United States coasts. This will include, in particular, new 

rights over all minerals (such as nodules and sulphide deposits) in the zone that are not on the 

continental shelf but are within 200 nautical miles. Deposits of polymetallic sulphides and 

cobalt/manganese crusts in these areas have only been recently discovered and are years away 

from being commercially recoverable. But they could be a major future source of strategic and 

other minerals important to the U.S. economy and security. 

The EEZ applies to waters adjacent to the United States, the Commonwealth of Puerto 

Rico, the Commonwealth of the Northern Mariana Islands (consistent with the Covenant and 

UN Trusteeship Agreement), and United States overseas territories and possessions. The total 

area encompassed by the EEZ has been estimated to exceed two million square nautical miles. 

The President's statement makes clear that the proclamation does not change existing policies with respect to the outer continental shelf and fisheries within the U.S. zone. 

Since President Truman proclaimed U.S. jurisdiction and control over the adjacent continental shelf in 1945, the U.S. has asserted sovereign rights for the purpose of exploration and 

exploitation of the resources of the continental shelf. Fundamental supplementary legislation, 

the Outer Continental Shelf Lands Act, was passed by Congress in 1953. The President's proclamation today incorporates existing jurisdiction over the continental shelf. 

Since 1976 the United States has exercised management and conservation authority over 

fisheries resources (with the exception of highly migratory species of tuna) within 200 nautical 

miles of the coasts, under the Magnuson Fishery Conservation and Management Act. The U.S. 

neither recognizes nor asserts jurisdiction over highly migratory species of tuna. Such species 

are best managed by international agreements with concerned countries. In addition to confirming the United States sovereign rights over mineral deposits beyond the continental shelf 

but within 200 nautical miles, the Proclamation bolsters U.S. authority over the living resources of the zone. 

26 
The United States has also exercised certain other types of jurisdiction beyond the territorial sea in accordance with international law. This includes, for example, jurisdiction relating 

to pollution control under the Clean Water Act of 1977 and other laws. 

The President has decided not to assert jurisdiction over marine scientific research in the 

U.S. EEZ. This is consistent with the U.S. interest in promoting maximum freedom for such 

research. The Department of State will take steps to facilitate access by U.S. scientists to foreign EEZ's under reasonable conditions. 

The concept of the EEZ is already recognized in international law and the President's 

Proclamation is consistent with existing international law. Over 50 countries have proclaimed 

some form of EEZ; some of these are consistent with international law and others are not. 

The concept of an EEZ was developed further in the recently concluded Law of the Sea 

negotiations and is reflected in that Convention. The EEZ is a maritime area in which the coastal state may exercise limited powers as recognized under international law. The EEZ is not 

the same as the concept of the territorial sea, and is beyond the territorial jurisdiction of any 

coastal statf~. 

The President's proclamation confirms that, without prejudice to the rights and jurisdiction of the United States in its EEZ, all nations will continue to enjoy non-resource related 

freedoms of the high seas beyond the U.S. territorial sea and within the U.S. EEZ. This means 

that the freedom of navigation and overflight and other internationally lawful uses of the sea 

will remain the same Within the zone as they are beyond it. 

The President has also established clear guidelines for United States oceans policy by stating that the United States is prepared to accept and act in accordance with international law 

as reflected in the results of the Law of the Sea Convention that relate to traditional uses of 

the oceans, such as navigation and overflight. The United States is willing to respect the 

maritime claims of others, including economic zones, that are consistent with international law 

as reflected in the Convention, if U.S. rights and freedoms in such areas under international 

law are respected by the coastal state. 

The President has not changed the breadth of the United States territorial sea. It remains 

at 3 nautical miles. The United States will respect only those territorial sea claims of others in 

excess of 3 nautical miles, to a maximum of 12 nautical miles, which accord to the U.S. its full 

rights under international law in the territorial sea. 

Unimpeded commercial and military navigation and overflight are critical to the national 

interest of the United States. The United States will continue to act to ensure the retention 

of the necessary rights and freedoms. 

By proclaiming today a U.S. EEZ and announcing other oceans policy guidelines, the President has demonstrated his commitment to the protection and promotion of U.S. maritime interests in a manner consistent with international law. 

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APPENDIX C 

PART VI, CONTINENTAL SHELF 

Article 76, Definition of the continental shelf 

1. The continental shelf of a coastal State comprises the sea-bed and subsoil of the submarine areas that extend beyond its territorial sea throughout the natural prolongation of its 

land territory to the outer edge of the continental margin, or to a distance of 200 nautical miles 

from the baselines from which the breadth of the territorial sea is measured where the outer 

edge of the continental margin does not extend up to that distance. 

2. The continental shelf of a coastal State shall not extend beyond the limits provided for 

in paragraph 4 to 6. 

3. The continental margin comprises the submerged prolongation of the land mass of the 

coastal State, and consists of the sea-bed and subsoil of the shelf, the slope and the rise. It does 

not include the deep ocean floor with its oceanic ridges or the subsoil thereof. 

4. (a) For the purposes of this Convention, the coastal State shall establish the outer edge 

of the continental margin wherever the margin extends beyond 200 nautical miles from the 

baselines from which the breadth of the territorial sea is measured, by either: 

(i) a line delineated in accordance with paragraph 7 by reference to the outermost 

fixed points at each of which the thickness of sedimentary rocks is at least 1 per cent of the 

shortest distance from such point to the foot of the continental slope; or 

(ii) a line delineated in accordance with paragraph 7 by reference to fixed points not 

more than 60 nautical miles from the foot of the continental slope. 

(b) In the absence of evidence to the contrary, the foot of the continental slope shall 

be determined as the point of maximum change in the gradient at its base. 

5. The fixed points comprising the line of the outer limits of the continental shelf on the 

sea-bed, drawn in accordance with paragraph 4 (a) (i) and (ii), either shall not exceed 350 nautical miles from the baselines from which the breadth of the territorial sea is measured or shall 

not exceed 100 nautical miles from the 2,500 metre isobath, which is a line connecting the depth 

of 2,500 metres. 

6. Notwithstanding the provisions of paragraph 5, on submarine ridges, the outer limit 

of the continental shelf shall not exceed 350 nautical miles from the baselines from which the 

breadth of the territorial sea is measured. This paragraph does not apply to submarine elevations that are natural components of the continental margin, such as its plateaux, rises, caps, 

banks and spurs. 

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7. The coastal State shall delineate the outer limits of its continental shelf, where that 

shelf extends beyond 200 nautical miles from the baselines from which the breadth of the territorial sea is measured, by straight lines not exceeding 60 nautical miles in length, connecting 

fixed points, defined by co- ordinates of latitude and longitude. 

8. Information on the limits of the continental shelf beyond 200 nautical miles from the 

baselines from which the breadth of the territorial sea is measured shall be submitted by the 

coastal State to the Commission on the Limits of the Continental Shelf set up under Annex II 

on the basis of equitable geographical representation. The Commission shall make recommendations to coastal States on matters related to the establishment of the outer limits of their continental shelf. The limits of the shelf established by a coastal State on the basis of these recommendations shall be final and binding. 

9. The coastal State shall deposit with the Secretary-General of the United Nations 

charts and relevant information, including geodetic data, permanently describing the outer 

limits of its continental shelf. The Secretary-General shall give due publicity thereto. 

10. The provisions of this article are without prejudice to the question of delimitation of 

the continental shelf between States with opposite or adjacent coasts. 

Article 77, Rights of the coastal State over the continental shelf 

1. The coastal State exercises over the continental shelf sovereign rights for the purpose 

of exploring it and exploiting its natural resources. 

2. The rights referred to in paragraph 1 are exclusive in the sense that if the coastal State 

does not explore the continental shelf or exploit its natural resources, no one may undertake 

these activities without the express consent of the coastal State. 

3. The rights of the coastal State over the continental shelf do not depend on occupation, 

effective or notional, or on any express proclamation. 

4. The natural resources referred to in this Part consist of the mineral and other non-living resources of the sea-bed and subsoil together with living organisms belonging to sedentary 

species, that is to say, organisms which, at the harvestable stage, either are immobile on or 

under the sea-bed or are unable to move except in constant physical contact with the sea-bed 

or the subsoil. 

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GPO 787-042/108