Introduction

This report summarizes the results 

of the Bureau of Ocean Energy 

Management (BOEM) 2011 assessment 

of the undiscovered oil and gas 

resources for the U.S. Outer Continental Shelf (OCS) (Figure 1) 

and the 2014 Atlantic Assessment Update included. The OCS 

comprises the portion of the submerged seabed whose mineral 

estate is subject to Federal jurisdiction. The 2011 assessment 

represents a comprehensive appraisal that considered relevant 

data and information available as of January 1, 2009 (December, 

2013 for Atlantic OCS), incorporates advances in petroleum 

exploration and development technologies, and employs new 

methods of resource assessment.

This assessment provides estimates of undiscovered, technically 

and economically recoverable oil and natural gas resources 

located outside of known oil and gas fields on the OCS. It 

considers recent geophysical, geological, technological, and 

economic information and utilizes a probabilistic play based 

approach to estimate the undiscovered technically recoverable 

resources of oil and gas for individual plays. This methodology 

is suitable for both conceptual plays where there is little or 

no specific information available, and for developed plays 

where there are discovered oil and gas fields and considerable 

information is available. After estimation, individual play results 

are aggregated to larger areas such as basins, planning areas, 

and regions. Estimates of the quantities of historical production, 

reserves, and future reserves appreciation are presented to 

provide a frame of reference. More detailed information about 

the geology, assessment methodology, and economics will be 

made available in separate regional assessment reports.

Commodities Assessed 

Commodities assessed are crude oil, natural gas liquids 

(condensate), and natural gas that exist in conventional reservoirs 

and are producible with conventional recovery techniques. Crude 

oil and condensate are reported jointly as oil; associated and 

nonassociated gas are reported as gas. Oil volumes are reported 

as billions of stock tank barrels of oil (Bbo) and gas as trillion 

standard cubic feet of gas (Tcfg). Oil-equivalent gas is a volume 

of gas (associated and/or nonassociated) expressed in terms of 

its energy equivalence to oil (i.e., 5,620 cubic feet of gas per 

barrel of oil). The combined volume of oil and oil-equivalent gas 

resources is referred to as barrel of oil-equivalent (BOE) and is 

reported in billions of barrels (Bbo). 

This assessment does not include potentially large quantities 

of hydrocarbon resources that could be recovered from known 

and future fields by enhanced recovery techniques. It also does 

not consider gas in geopressured brines, or oil and natural gas 

that may be present in insufficient quantities or quality (low 

permeability “tight” reservoirs) to be produced by conventional 

recovery techniques. 

Estimates of undiscovered recoverable resources are presented in 

two categories; undiscovered technically recoverable resources 

(UTRR), and undiscovered economically recoverable resources 

Washington/

Oregon

Northern

California

Central

California

Southern

California

North

Atlantic

MidAtlantic

South

Atlantic

Straits

of Florida

Eastern Gulf

of Mexico

Central Gulf

of Mexico

Western Gulf

of Mexico

Bowers

Basin

Aleutian

Basin

Navarin

Basin

Chukchi Sea

Aleutian Arc

St. George

Basin

Shumagin North

Aleutian

Basin

Kodiak

Gulf of 

Alaska

Cook Inlet

Beaufort Sea

ALASKA

Hope 

Basin

Norton

Basin

St. Matthew-Hall

Assessment of Undiscovered Technically Recoverable 

Oil and Gas Resources of the Nation’s Outer Continental 

Shelf, 2011(Includes 2014 Atlantic Update)

Using a play based assessment 

methodology, the Bureau of Ocean 

Energy Management estimates 

a mean of 90.02 billion barrels 

of undiscovered technically 

recoverable oil and mean of 404.60 

trillion cubic feet of undiscovered 

technically recoverable natural gas 

in the Federal Outer Continental 

Shelf of the United States.

Figure 1. Federal Outer Continental Shelf Areas of the United States.

BOEM Fact Sheet RED-2014-01c

Revised December 2014
(UERR). UTRR estimates are presented at 95th and 5th percentile

 levels, as well as at the mean level. This range of estimates 

corresponds to a 95-percent probability (a 19 in 20 chance) and 

a 5-percent probability (a 1 in 20 chance) of there being more 

than those amounts present, respectively. The 95- and 5-percent 

probabilities are considered reasonable minimum and maximum 

values, and the mean is the average or expected value. UERR 

results are presented as price-supply curves which show the 

relationship of price to economically recoverable resource. Price 

supply curves couple oil prices with gas prices based on the 

current gas market. Due to fluctuations in the economic value of 

gas, the 2011 assessment analyzed three different British Thermal 

Unit (BTU) based price pairings between oil and gas. These 

pairings represent gas prices that assume a 40 percent, 60 percent 

and 100 percent economic value of gas relative to oil on a BTU 

basis. 

Methodology

This assessment incorporates a play-based (see list of terms) 

approach toward the analysis of hydrocarbon potential. A 

major strength of this method is a strong relationship between 

information derived from oil and gas exploration activities and 

the geologic model developed by the assessment team. An 

extensive effort was undertaken in developing play models, 

delineating the geographic limits of each play, and compiling 

data on geologic and reservoir engineering parameters. These 

parameters are used in the determination of the total quantities 

of recoverable resources in each play. 

Probabilistic methods are employed to 

account for the inherent uncertainties 

associated with an assessment of 

undiscovered resources. Results 

are reported as a range of values 

corresponding to different probabilities of 

occurrence.

Due to sparse data from the majority 

of the plays in the Alaska, Atlantic and 

portions of the Pacific OCS Regions, 

analog plays are developed with a 

subjective approach to cover the range of 

uncertainties associated with these plays. 

For mature areas with significant amounts 

of data, such as the Gulf of Mexico and 

southern California, plays were analyzed 

by combining the subjective methodology 

utilizing historical trends, with a discovery based approach to 

account for the existing discovered pools. The economic portion 

of the assessment incorporates a wide range of oil and gas price 

points and utilizes a relationship between the cost of exploration 

and development and commodity prices.

Technology

Technological advances in hydrocarbon exploration and 

development occur on a near continuous basis, yet the nature of 

advancement is hard to predict and its impact difficult to estimate. 

Past experience indicates most technological breakthroughs 

occur during periods when commodity prices are high. For 

this assessment, recent technological advances in gathering, 

processing, and interpreting seismic data contributed to the 

identification and delineation of geological plays and to the 

development of geologic parameters used to model the plays. 

Similarly, recent technological advances in offshore drilling and 

development operations were incorporated through assumptions 

associated with the costs of these activities. Although no attempt 

has been made to develop an empirical relationship between 

the future technological advancements and the estimated 

undiscovered resources, BOEM believes that future advances 

will significantly affect the portion of the undiscovered resources 

represented by estimates of UTRR, resulting in an increased 

percentage being classified as economically recoverable 

resources.

Assessment Results

This assessment represents a multi-year effort that includes data 

and information available as of January 1, 2009 (December, 

2013 for Atlantic OCS). Estimates of UTRR for the entire OCS 

range from 67.44 Bbo at the P95 percentile to 120.72 Bbo at 

the P5 percentile with a mean of 90.02 Bbo (Figure 2 and Table 

1). Similarly, gas estimates range from 306.59 Tcfg to 552.69 

Tcfg with a mean of 404.60 Tcfg. On a BOE basis 55 percent 

of the potential resources are located within the Gulf of Mexico. 

The Alaska OCS ranks second with 31 percent. The Pacific is 

third among the regions in terms of oil potential and fourth with 

respect to gas. The Atlantic region ranks third when considering 

gas potential and fourth in terms of oil.

Estimates of UERR are presented as price-supply curves for 

the entire OCS in Figure 3, and Appendix A has price supply 

curves for individual regions. A price-supply curve shows 

the relationship of price to economically recoverable resource 

volumes (i.e., a horizontal line from the price axis to the curve 

yields the quantity of economically recoverable resources at the 

selected price). Price-supply curves represent resources available 

given sufficient exploration and development efforts and do not 

imply an immediate response to price changes. The price-supply 

Atlantic Gulf of Pacic

Mexico

Alaska

26.61

4.72

48.40

10.20

131.45

16.10 37.51

219.46

11.40

87.45

13.07

Oil (Bbo) Gas (Tcfg) BOE (Bbo)

50.00

Figure 2. Mean Undiscovered Technically Recoverable Resources by type and region.
charts contain two curves and two price scales, one for oil (green) 

and one for gas (red). The curves represent mean values at any 

specific price. The two vertical lines indicate the mean estimates 

of UTRR oil and gas resources for the specific area or region. 

At high prices, the economically recoverable resource volumes 

approach the technically recoverable volumes. 

The oil and gas price-supply curves are not independent of each 

other; that is, one specific oil price cannot be used to obtain an 

oil resource while a separate unrelated gas price is used to obtain 

a gas resource. The gas price is dependent on the oil price and 

must be used in conjunction with the oil price on the opposite 

axis of the chart to calculate resources. This is because oil and 

gas frequently occur together and individual pool economics 

are calculated using the coupled pricing. A different gas price 

associated with the oil price would result in a different resource 

value than that shown on the curve. Due to fluctuations in the 

economic value of gas relative to oil, three different BTU based 

price pairings for oil and gas were analyzed. Table 2 presents 

specific price pairs associated with a 40 percent economic value 

of gas relative to oil. 

Estimates of the total endowment, consisting of the sum 

of historic production, remaining reserves, future reserves 

appreciation, and UTRR are also presented in Table 3. Mean 

estimates of the total endowment for the entire OCS are about 

127 Bbo and 650 Tcfg, or 243 BBOE. 

After more than 60 years of OCS exploration and development, 

66 percent of the total endowment on a mean BOE basis remains 

undiscovered and is represented by the UTRR; more than 20 

percent of the total endowment has already been produced; 14 

percent is attributed to remaining reserves and appreciation.

Table 1. Undiscovered Technically Recoverable Resources of OCS Planning Areas.

Resource values are in billion barrels of oil (Bbo), and trillion cubic of gas (Tcfg). 95% indicates a 95 percent 

chance of at least the amount listed, 5% indicates a 5 percent chance of at least the amount listed. Only mean values 

are additive. Some total mean values may not equal the sum of the component values due to independent rounding. 

Values for UTRR results are for both leased and unleased lands of the Federal OCS.

Region 

Planning Area

Undiscovered Technically Recoverable Oil and Gas

Resources (UTRR)

Oil (Bbo) Gas (Tcfg) BOE (Bbo)

95% Mean 5% 95% Mean 5% 95% Mean 5%

Alaska OCS* 8.81 26.61 55.53 47.43 131.45 271.04 17.25 50.00 103.77

Chukchi Sea 2.32 15.38 40.08 10.32 76.77 209.53 4.15 29.04 77.36

Beaufort Sea 0.41 8.22 23.24 0.65 27.64 72.18 0.53 13.14 36.08

Hope Basin 0.00 0.15 0.60 0.00 3.77 14.98 0.00 0.82 3.27

Navarin Basin 0.00 0.13 0.62 0.00 1.22 5.80 0.00 0.35 1.65

North Aleutian Basin 0.02 0.75 2.50 0.40 8.62 23.28 0.09 2.29 6.65

St. George Basin 0.00 0.21 0.79 0.00 2.80 11.15 0.00 0.71 2.77

Norton Basin 0.00 0.06 0.24 0.00 3.06 13.27 0.00 0.60 2.61

Cook Inlet 0.06 1.01 2.85 0.03 1.20 3.48 0.06 1.23 3.47

Gulf of Alaska 0.00 0.63 2.04 0.00 4.04 13.87 0.00 1.34 4.51

Shumagin 0.00 0.01 0.05 0.00 0.49 2.04 0.00 0.10 0.42

Kodiak 0.00 0.05 0.20 0.00 1.84 7.62 0.00 0.38 1.55

*The Aleutian Arc, Aleutian Basin, Bowers Basin, and St. Matthew-Hall Planning Areas in the Alaska OCS Region were not evaluated in this study as their petroleum potential is negligible.

Atlantic OCS 1.32 4.72 9.23 11.81 37.51 67.69 3.42 11.40 21.27

North Atlantic 0.06 1.75 5.19 1.05 11.94 32.53 0.25 3.88 10.98

Mid-Atlantic 0.06 2.42 5.58 1.01 23.38 48.45 0.24 6.58 14.20

South Atlantic 0.00 0.55 1.16 0.00 2.18 6.31 0.00 0.94 2.29

Gulf of Mexico OCS 38.86 48.40 59.18 193.99 219.46 245.25 73.38 87.45 102.82

Western Gulf of Mexico 8.58 12.38 17.15 57.39 69.45 81.94 18.79 24.74 31.73

Central Gulf of Mexico 22.54 30.93 40.69 111.77 133.90 156.62 42.43 54.76 68.55

Eastern Gulf of Mexico 3.46 5.07 6.95 12.34 16.08 20.68 5.66 7.93 10.63

Straits of Florida 0.01 0.02 0.03 0.01 0.02 0.03 0.01 0.02 0.03

Pacific OCS 6.73 10.20 14.30 10.11 16.10 23.75 8.53 13.07 18.52

Washington/Oregon < 0.01 0.40 1.15 0.03 2.28 5.79 0.01 0.81 2.18

Northern California 1.08 2.08 3.54 2.13 3.58 5.38 1.46 2.71 4.50

Central California 1.23 2.40 3.87 1.18 2.49 4.15 1.44 2.84 4.61

Southern California 2.52 5.32 8.83 3.27 7.76 14.42 3.10 6.70 11.40

Total U.S. OCS 67.44 90.02 120.72 306.59 404.60 552.69 121.99 162.01 219.07
Table 2. Undiscovered Economically Recoverable Resources of OCS Planning Areas.

Resource values are in billion barrels of oil (Bbo), and trillion cubic of gas (Tcfg). Some total mean values may not equal the sum of the component 

values due to independent rounding. Prices are in dollars per barrel($/Bbl) for oil, and dollars per thousand cubic feet ($/Mcf) for gas. Table 2 

represents a gas price adjustment of 0.4. Values for UERR results are for both leased and unleased lands of the Federal OCS.

Region 

Planning Area

Undiscovered Economically Recoverable Oil and Gas

Resources (UERR)

$30/Bbl

$2.14/Mcf

$60/Bbl

$4.27/Mcf

$90/Bbl

$6.41/Mcf

$110/Bbl

$7.83/Mcf

$120/Bbl

$8.54/Mcf

$160/Bbl

$11.39/Mcf

Oil Gas Oil Gas Oil Gas Oil Gas Oil Gas Oil Gas 

Alaska OCS* 1.21 1.20 11.45 19.55 17.77 42.16 20.05 57.05 20.93 64.09 22.97 85.26

Chukchi Sea 0.00 0.00 5.18 10.66 9.87 28.14 11.50 38.54 12.10 43.13 13.42 55.95

Beaufort Sea 0.25 0.15 4.40 5.30 5.78 8.88 6.32 11.61 6.53 12.95 7.10 17.40

Hope Basin 0.00 0.00 0.01 0.02 0.03 0.07 0.04 0.11 0.04 0.13 0.05 0.31

Navarin Basin 0.00 0.00 0.02 0.03 0.04 0.10 0.05 0.16 0.05 0.20 0.07 0.33

North Aleutian Basin 0.25 0.10 0.45 0.30 0.52 0.88 0.56 1.98 0.58 2.66 0.65 4.74

St. George Basin 0.00 0.00 0.05 0.05 0.08 0.10 0.09 0.14 0.09 0.18 0.12 0.60

Norton Basin 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.25

Cook Inlet 0.58 0.25 0.94 0.80 0.99 0.97 1.00 1.03 1.00 1.05 1.01 1.10

Gulf of Alaska 0.13 0.71 0.40 2.40 0.48 2.87 0.50 3.04 0.51 3.10 0.54 3.28

Shumagin 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.02 0.00 0.07

Kodiak 0.00 0.00 0.00 0.00 0.01 0.13 0.02 0.47 0.02 0.67 0.03 1.22

*The Aleutian Arc, Aleutian Basin, Bowers Basin, and St. Matthew-Hall Planning Areas in the Alaska OCS Region were not evaluated in this study as their petroleum potential is negligible.

Atlantic OCS 2.61 9.82 3.29 17.27 3.53 21.08 3.63 22.52 3.67 23.15 3.79 25.01

North Atlantic 1.20 4.22 1.42 6.45 1.49 7.44 1.52 7.80 1.53 7.96 1.56 8.44

Mid-Atlantic 1.35 5.02 1.78 9.93 1.93 12.60 1.98 13.64 2.00 14.08 2.06 15.37

South Atlantic 0.06 0.58 0.09 0.89 0.12 1.04 0.13 1.09 0.14 1.12 0.17 1.19

Gulf of Mexico OCS 32.74 129.92 40.29 172.06 42.80 185.94 43.64 190.46 43.97 192.25 44.93 197.53

Western Gulf of Mexico 8.28 43.72 10.29 57.44 10.96 61.46 11.19 62.71 11.28 63.20 11.53 64.59

Central Gulf of Mexico 21.17 78.09 25.95 103.99 27.52 112.77 28.04 115.61 28.25 116.74 28.85 120.05

Eastern Gulf of Mexico 3.28 8.12 4.05 10.62 4.31 11.71 4.40 12.13 4.43 12.31 4.54 12.88

Straits of Florida 0.01 < 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01

Pacific OCS 4.32 5.81 6.67 8.80 7.43 9.90 7.69 10.31 7.79 10.49 8.11 11.05

Washington/Oregon 0.11 0.39 0.21 0.74 0.24 0.89 0.25 0.96 0.26 0.99 0.28 1.09

Northern California 0.66 0.74 1.18 1.37 1.37 1.66 1.44 1.78 1.47 1.83 1.55 2.00

Central California 1.44 1.52 1.95 2.05 2.10 2.20 2.15 2.24 2.17 2.26 2.22 2.31

Southern California 2.12 3.17 3.33 4.65 3.71 5.15 3.84 5.33 3.90 5.40 4.06 5.66

Total U.S. OCS 41.02 146.91 61.80 217.81 71.67 259.18 75.15 280.49 76.45 290.10 79.93 318.91

Figure 3. Price supply curve of the entire United States OCS.

1.42

2.85

8.54

7.12

5.69

4.27

9.96

11.39

12.81

14.23

0 50 100 150 200 250 300 350 400 450

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

$160.00

$180.00

$200.00

0 10 20 30 40 50 60 70 80 90 100

Gas Price

UERR Gas (Tcfg)

Oil Price

UERR Oil (Bbo)

Gas Market Value Adjustment 0.4

United States OCS

UTRR Oil UERR Oil

UTRR Gas UERR Gas

.
Comparison with Previous Assessments

A comparison of 1996, 2001, 2006, 2011, and 2014 Atlantic 

update UTRR assessment results is shown on Figure 4. At the 

mean level, the estimates of UTRR for the entire OCS represent 

an increase of 1.43 Bbo (about 2 percent) for oil when compared 

to the previous (2011) assessment and an increase of 6.23 Tcfg 

for gas (about 2 percent). Comparisons of the assessments for 

each OCS region can be found in Appendix B.

In the Gulf of Mexico, estimates for oil increased from 44.92 

Bbo to 48.40 Bbo (8 percent), while estimates for gas decreased 

from 232.54 Tcfg to 219.46 Tcfg (6 percent). The increase in 

oil estimates are attributed to new deepwater discoveries while 

decreases in gas are attributed to declines in gas production on 

the shelf.

The Pacific OCS Region mean UTRR estimates of 10.20 Bbo 

and 16.10 Tcfg represent a slight decrease 

for both oil and natural gas when compared 

to the previous assessment. The only new 

activities occurring in the region since 

the last assessment were in the existing 

producing fields in the Southern California 

Planning Area. 

The Atlantic OCS Region mean estimates 

of UTRR were updated in 2014 to 4.72 Bbo 

and 37.51 Tcfg. This represents a 43 percent 

increase in oil resources and a 20 percent 

increase in gas resources as compared to 

the 2011 assessment. These differences are 

attributed to improved seismic interpretation 

techniques as well as incorporating 

information from new analogs that have been 

discovered since the previous assessment. 

The change in mean UTRR for the Atlantic OCS is a result of 

revisions within four of the ten Atlantic geologic plays. Mean 

UTRR within two plays increased significantly since the 2011 

assessment because of rapid evolution of analogous East African 

discoveries, which increased both the number of discoveries and 

the field sizes in the analog database. On average, the mean pool 

size for the two plays increased from approximately 40 million 

BOE in 2011 to approximately 105 million BOE in 2014.

Mean estimates of UTRR for the Alaska OCS Region remain 

relatively unchanged in comparison to the previous assessment 

at 26.61Bbo and 131.45 Tcfg. There has been no significant 

new geologic data gathered in the region and none of the leases 

acquired since the previous assessment have been tested. 

0

20

40

60

80

100

120

130

5th percentile

95th percentile

Mean

MMS 1996

MMS 2001

MMS 2006

BOEM 2011

BOEM 2014

MMS 1996

MMS 2001

MMS 2006

BOEM 2011

BOEM 2014

0

100

200

300

400

500

600

700

0

Billion Barrels of Oil

Trillion Cubic Feet of Gas

United States 

OCS

Figure 4. UTRR from BOEM 1996, 2001, 2006, 2011, and 2014 Atlantic update.

Table 3. Distribution of total hydrocarbon endowment by type, region, and resource 

category. Some total mean values may not equal the sum of the component values due to 

independent rounding. 

Resource Category

Endowment for the U.S. OCS

Alaska Atlantic Gulf of 

Mexico Pacific Total OCS

Cumulative 

Production

Oil (Bbo) 0.01 0 17.59 1.28 17.18

Gas (Tcf) 0 0 181.06 1.74 173.44

BOE (Bbo) 0.01 0 49.81 1.58 48.04

Reserves

Oil (Bbo) 0.03 0 4.32 1.61 10.80

Gas (Tcf) 0 0 11.30 1.97 24.11

BOE (Bbo) 0.03 0 6.34 1.75 15.09

Reserves 

Appreciation

Oil (Bbo) - - 9.52 - 9.52

Gas (Tcf) - - 48.47 - 48.47

BOE (Bbo) - - 18.15 - 18.15

UTRR 

(Mean)

Oil (Bbo) 26.61 4.72 48.40 10.20 90.02

Gas (Tcf) 131.45 37.51 219.46 16.10 404.60

BOE (Bbo) 50.00 11.40 87.45 13.07 162.01

Total 

Endowment

Oil (Bbo) 26.65 4.72 83.13 12.93 127.52

Gas (Tcf) 131.45 37.51 462.60 18.98 650.62

BOE (Bbo) 50.04 11.40 165.44 16.32 243.29
List of Terms

Analogous Reservoirs: as used in resources assessments, have 

similar rock and fluid properties, reservoir conditions (depth, 

temperature and pressure) and drive mechanisms, but are 

typically at a more advanced stage of development than the 

reservoir of interest and thus may provide concepts to assist in the 

interpretation of more limited data and estimation of recovery.

British Thermal Unit: The amount of heat required to raise 

the temperature of one pound (0.454 kg) of liquid water by one 

degree Fahrenheit at a constant pressure of one atmosphere.

Conventionally Recoverable: Producible by natural pressure, 

pumping, or secondary recovery methods, such as gas or water 

injection.

Cumulative Production: The sum of all produced volumes of oil 

and gas prior to a specified point in time.

Field: Area consisting of a single reservoir or multiple reservoirs 

all grouped on, or related to, the same general geologic structural 

feature and/or stratigraphic trapping condition. There may be 

two or more reservoirs in a field that are separated vertically by 

impervious strata, laterally by local geologic barriers, or by both.

Pool: A discovered or undiscovered accumulation of 

hydrocarbons, typically within a single stratigraphic interval.

Play: A group of pools that share a common history of 

hydrocarbon generation, migration, reservoir development, and 

entrapment.

Probability: A means of expressing an outcome on a numerical 

scale that ranges from impossibility to absolute certainty; the 

chance that a specified event will occur.

Prospect: A geologic feature having the potential for trapping 

and accumulating hydrocarbons; a pool or potential field.

Reserves: The quantities of hydrocarbon resources anticipated 

to be recovered from known accumulations from a given 

date forward. All reserve estimates involve some degree of 

uncertainty.

Reserves Appreciation: The observed incremental increase 

through time in the estimates of reserves (proved and unproved) 

of an oil and/or natural gas field as a consequence of extension, 

revision, improved recovery, and the addition of new reservoirs.

Resources: Concentrations in the earth’s crust of naturally 

occurring liquid or gaseous hydrocarbons that can conceivably be 

discovered and recovered.

Total Endowment: All technically recoverable hydrocarbon 

resources of an area. Estimates of total endowment equal 

the sum of undiscovered technically recoverable resources, 

cumulative production, proved reserves, unproved reserves and 

reserves appreciation.

Undiscovered Resources: Resources postulated, on the basis of 

geologic knowledge and theory, to exist outside of known fields 

or accumulations.

Undiscovered Technically Recoverable Resources (UTRR):Oil 

and gas that may be produced as a consequence of natural 

pressure, artificial lift, pressure maintenance, or other secondary 

recovery methods, but without any consideration of economic 

viability. They are primarily located outside of known fields.

Undiscovered Economically Recoverable Resources (UERR): 

The portion of the undiscovered technically recoverable resources 

that is economically recoverable under imposed economic and 

technologic conditions.

Selected References

Minerals Management Service. 1996: An assessment of the 

undiscovered hydrocarbon potential of the Nation’s Outer 

Continental Shelf. OCS Report MMS 96-0034, 40 p.

Minerals Management Service. 2006: Assessment of 

Undiscovered Technically Recoverable Oil and Gas Resources 

of the Nation’s Outer Continental Shelf. MMS Fact Sheet RED2006-01b, 6 p.

Minerals Management Service. 2006:Planning Area Resources 

Addendum to Assessment of Undiscovered Technically 

Recoverable Oil and Gas Resources of the Nation’s Outer 

Continental Shelf. MMS Fact Sheet RED-2006-02, 2 p.

Society of Petroleum Engineers and World Petroleum Congress. 

1997: Petroleum Reserves Definitions, p. 4-7.

For Further Information

Supporting geological studies, previous assessment results, and 

methodologies used by BOEM for resource assessment can be 

found on BOEM’s web site, www.boem.gov.

For further information on this study please contact:

Richard Desselles, 703-787-1568

richard.desselles@boem.gov

For detailed regional information please contact:

Alaska OCS: Rance Wall, 907-334-5321

 rance.wall@boem.gov

Atlantic OCS: David Cooke, 504-736-2609

 david.cooke@boem.gov

Gulf of Mexico OCS: David Cooke, 504-736-2609

 david.cooke@boem.gov

Pacific OCS: Joan Barminski, 805-384-6337

 joan.barminski@boem.gov
Appendix A

Gulf of Mexico OCS

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

$160.00

$180.00

$200.00

0 10 20 30 40 50 60

UERR Oil (Bbo)

Oil Price

0 50 100 150 200 250

UERR Gas (Tcfg)

Gas Price

Geologic Oil Economic Oil

Gas Market Value Adjustment 0.4 Geologic Gas Economic Gas

1.42

2.85

8.54

7.12

5.69

4.27

9.96

11.39

12.81

14.23

Pacific OCS

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

$160.00

$180.00

$200.00

0 2 4 6 8 10 12

UERR Oil (Bbo)

Oil Price

0 2 4 6 8 10 12 14 16 18

UERR Gas (Tcfg)

Gas Price

Geologic Oil Economic Oil Gas Market Value Adjustment 0.4 Geologic Gas Economic Gas

1.42

2.85

8.54

7.12

5.69

4.27

9.96

11.39

12.81

14.23

Price supply curves for the four OCS regions. Each graph shows the economic and geologic resources obtainable at various oil prices. 

In these graphs, oil prices are coupled with a specific gas price assuming a 40 percent economic value of gas relative to oil. This value 

of gas is intended to model economic conditions assuming new supplies of natural gas for North American markets are influenced by 

emerging unconventional sources of natural gas (shale gas, coal bed methane, tight gas sands) onshore. Price-supply curves representing a 60 percent and 100 percent economic value of gas relative to oil are available in the detailed assessment report at 

www.boem.gov.

Alaska OCS

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

$160.00

$180.00

$200.00

0 5 10 15 20 25 30

UERR Oil (Bbo)

Oil Price

0 20 40 60 80 100 120 140

UERR Gas (Tcfg)

Gas Price

Geologic Oil Economic Oil Gas Market Value Adjustment 0.4 Geologic Gas Economic Gas

1.42

2.85

8.54

7.12

5.69

4.27

9.96

11.39

12.81

14.23

Atlantic OCS

$20.00

$40.00

$60.00

$80.00

$100.00

$120.00

$140.00

$160.00

$180.00

$200.00

UERR Oil (Bbo)

Oil Price

UERR Gas (Tcfg)

Gas Price

Geologic Oil Economic Oil Geologic Gas Economic Gas Gas Market Value Adjustment 0.4

0 5 10 15 20 25 30 35 40

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

.

1.42

2.85

8.54

7.12

5.69

4.27

9.96

11.39

12.81

14.23
Appendix B

The graphs below show comparisons of UTRR by OCS region for assessments made in 1996, 2001, 2006, and 2011, with 2014 

in addition for the Atlantic. The bars represent the range between 95th and 5th percentiles for both oil and gas. Mean values are 

presented as a point on the range bars. These figures help illustrate how the values have changed through time. Changes in estimates 

reflect subsequent production, discoveries, data acquisitions, and application of new or improved exploration and production 

technologies.

0

 5

10

15

20

 25

 30

5th percentile

95th percentile

Billion Barrels of Oil

Mean

Pacific 1996

Pacific 2001

Pacific 2006

Pacific 2011

Pacific 1996

Pacific 2001

Pacific 2006

Pacific 2011

0

 5

 10

 15

 20

 25

 30

Trillion Cubic Feet of Gas

0

0

 2

 4

 6

 8

 10

 12

 14

5th percentile

95th percentile

Mean

Billion Barrels of Oil

Atlantic 1996

Atlantic 2006

Atlantic 2001

Atlantic 2011

Atlantic 2014

Atlantic 1996

Atlantic 2001

Atlantic 2006

Atlantic 2011

Atlantic 2014

0

 10

 20

 30

 40

 50

 60

Trillion Cubic Feet of Gas

0

 70

0

10

20

30

40

 50

 60

5th percentile

95th percentile

Mean

Billion Barrels of Oil

Alaska 1996

Alaska 2001

Alaska 2006

Alaska 2011

Alaska 1996

Alaska 2001

Alaska 2006

Alaska 2011

0

 50

 100

 150

 200

 250

 300

Trillion Cubic Feet of Gas

0

0

10

20

30

40

 50

 60

5th percentile

95th percentile

Mean

Billion Barrels of Oil

Gulf of Mexico 1996

Gulf of Mexico 2001

Gulf of Mexico 2006

Gulf of Mexico 2011

Gulf of Mexico 1996

Gulf of Mexico 2001

Gulf of Mexico 2006

Gulf of Mexico 2011

0

 50

 100

 150

 200

 250

 300

Trillion Cubic Feet of Gas

0