U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

THE CONTRIBUTION OF GIANT FIELDS TO UNITED STATES OIL PRODUCTION AND RESERVES

by

James W. Schmoker

Open-File Report 99-131

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

U.S. Geological Survey, Mail Stop 939, Denver Federal Center, Denver, CO 80225

1999

INTRODUCTION

In the U.S., an oil field is regarded as "giant" if the sum of cumulative production and remaining (proved) reserves exceeds 100 million barrels of oil (mmbo). Giant fields account for a very small fraction of the total number of oil fields discovered in the U.S., but their importance to U.S. production - past and future - vastly exceeds their numerical proportion.

This report presents and interprets production and reserves data for giant U.S. oil fields, for the purpose of better understanding and forecasting U.S. oil production and the U.S. resource base. The primary data used here are arranged by location in two tables. Table 1 provides data for giant U.S. oil fields as of 1/1/98: this table contains field name and location; year of discovery; annual production in 1997; cumulative production, remaining reserves, and the sum of these two quantities (estimated total recovery) as of 1/1/98; and the ratio of remaining reserves to 1997 annual production. Table 2 lists those fields of Table 1 for which production and reserves data were also published in 1990: this table introduces columns for cumulative production, remaining reserves, and estimated total recovery as of 1/1/90; and the change in estimated total recovery between 1/1/90 and 1/1/98.

The data of Table 1 offer a snapshot of production and reserves characteristics of giant fields at one point in time. The estimated size (cumulative production plus proved reserves) of an oil field can change significantly over a relatively short time span because proved reserves are dependent upon factors that do not remain constant: the data of Table 2 capture changes in the sizes of many of these giant fields in the first eight years of the 1990's.

PRODUCTION AND RESERVES AS OF 1/1/98

The list of giant U.S. oil fields presented in Table 1, derived from the International Petroleum Encyclopedia (1998), is probably not exhaustive but appears to be reasonably complete. The implicit assumption is made here that Table 1 is sufficiently inclusive to warrant analysis. Table 1 could be incomplete due to: 1) the general vagaries of data collection and data bases; 2) omission of older fields that recently attained giant-field status; and 3) omission of recently discovered large fields.

Perspectives

The 293 giant U.S. oil fields, of which 16 have estimated total recoveries exceeding 1 billion barrels of oil (bbo), account for about 58% of the discovered oil in the U.S., and for 59% of cumulative U.S. oil production (Figure 1). These fields have contributed substantially to the economic development of the U.S.

As of 1/1/98, the estimated total recovery of oil from all giant fields in the U.S. was 113.1 bbo (Figure 1), which is roughly equivalent to that of Iran or Kuwait (see Masters and others, 1994). Only the Former Soviet Union has produced more oil (128.1 bbo) than the 101.8 bbo produced from giant U.S. oil fields (International Petroleum Encyclopedia, 1998). The giant U.S. oil fields, of themselves, would constitute a world-class oil "country".

The median discovery year for giant U.S. oil fields is 1935, and 90% of their recoverable oil has been produced (Figure 1). Their median and average ratios of remaining oil reserves to annual oil production are low. These data show that the giant oil fields of the U.S. form a mature

1

producing sector. However, production from these fields is still significant, even on a world scale. Production from giant U.S. oil fields averaged 3.65 mmbo/day in 1997, which is equal to 57% of daily U.S. oil production (Figure 1) and is a rate exceeded worldwide only by Saudi Arabia and the Former Soviet Union (International Petroleum Encyclopedia, 1998).

Fields Having Significant Remaining Potential

The previous discussion did not differentiate between giant fields which have significant remaining potential and those which appear to be in terminal decline. The former fields represent the future of the group; the latter fields have become, at a National perspective, part of history.

The remaining potential of giant U.S. oil fields is evaluated here on the basis of remaining reserves (as of 1/1/98) and annual production (in 1997). Figure 2 shows that, for both measures of remaining potential, relatively few fields account for most of the oil.

Fifty percent of 1997 annual production from all giant U.S. oil fields came from just 11 fields and 80% was supplied by 55 fields (Figure 2A). The distribution of remaining reserves is yet more uneven. As of 1/1/98, 50% of remaining reserves in all giant U.S. oil fields resided in just six fields and 80% was accounted for by 42 fields (Figure 2B).

Using the somewhat arbitrary criteria that giant fields having significant remaining potential are those that account for either 80% of total annual production or 80% of total remaining reserves, 59 giant U.S. oil fields are identified here as having significant remaining potential (Table 3). Of these, 38 fields qualify with respect to both annual production and remaining reserves.

The giant U.S. oil fields having significant remaining potential (Table 3) form a diverse group. They are distributed among 10 states, although most are located in Texas, California, and Louisiana (Figure 3). Common geologic features among these fields, other than access to an excellent oil-charge system, are not obvious, nor are they obvious for giant U.S. oil fields in general.

Field-Size and Oil-Volume Distributions

The field-size distribution of the 293 giant U.S. oil fields listed in Table 1 is extremely skewed (Figure 4A). The coefficient of skewness is 9.1. (A skewness coefficient greater than 1.0 is commonly considered to indicate a highly skewed distribution.) Note that the eye tends to be fooled by Figure 4A: the logarithmic size-category axis, necessary to construct a legible figure, greatly foreshortens the larger field-size categories and thus reduces the apparent skewness.

One hundred and fifty-one fields (almost 52%) have sizes between 100 and 200 mmbo, whereas only eight fields (about 3%) have sizes in the much larger range between 1,600 and 12,800 mmbo (Figure 4A). The biggest field of the group (Prudhoe Bay) is about 65 times larger than the median field of 194 mmbo. If this ratio were to be applied to the height of humans, a median adult height of 5.5 feet would imply the existence of people as tall as 358 feet.

Approximately equal volumes of oil are attributed to field-size categories 1, 2, and 3 (Figure 4B). The volume of oil ascribed to field-size categories 4 through 7 tends to decrease as

size category increases. (Data for size categories 6 and 7 are erratic because each category contains only one field.)

The U.S. is the most thoroughly explored large petroleum region in the world. As such, the field-size and oil-volume distributions for discovered giant U.S. oil fields (Figure 4) might provide as close an approximation to a natural (in situ) population of such fields as is presently known. For this reason, the distributions of Figure 4 could have value as analogs for some of the less explored regions of the world.

CHANGES IN FIELD SIZES BETWEEN 1/1/90 AND 1/1/98

The sizes (estimated total recoveries) of U.S. oil fields commonly change over time, in response to a large number of geological, technical, economic, and regulatory factors (e.g., Arrington, 1960; Attanasi and Root, 1994; Gautier and others, 1995; Schmoker and Crovelli, 1998). Recent changes in the sizes of 209 giant U.S. oil fields (of the 293 fields considered in the previous sections) can be examined here, using the production and reserves data as of 1/1/90 that are provided in Table 2.

Field-Size Changes Measured as Percentages

The great majority (96%) of the fields listed in Table 2 were 20 or more years old at the beginning of 1990; about two-thirds were discovered prior to 1941 (Figure 5). Almost all the fields are well past the period of initial development in which large changes in estimated total recovery can be expected to occur as a field is delineated and production practices are optimized. All U.S. fields are subject to a standard system for reporting remaining reserves, which minimizes capricious field-size changes. One might therefore think that after many years of development and production, the remaining potential of most of these giant oil fields should be well established, but Figure 6 shows that this is not the case.

Of the 209 fields in the data set of Table 2, the size of only 30 fields (14%) remained essentially unchanged on a percentage basis (larger or smaller by 0.5% or less) between 1/1/90 and 1/1/98 (Figure 6A). Sixty-five fields (31%) increased or decreased in size by 0-.5 to 4% in this eight-year period, 52,6^^ (25%) changed in size by 4 to 10%, and 62 fields (30%) changed in size by more than 10%. (These percentage changes are relative to 1/1/90 sizes.) From these data it is apparent that significant adjustments in estimated total recovery have been the norm, and not the exception, for giant U.S. oil fields in the first eight years of the 1990's.

Furthermore, Figure 6A shows that field-size increases outnumbered field-size decreases by more than two to one. Excluding the 30 fields with little percentage change, 126 fields increased in size whereas 53 fields decreased in size.

Production and reserves data as of 1/1/90 are available for 48 of the 59 giant U.S. oil fields having significant remaining potential. The percent-change distribution for these 48 fields (Figure 6B) is weighted more heavily to the right than the distribution for the entire group of giant fields (Figure 6A). Of the fields with significant remaining potential, the size of seven fields remained essentially unchanged on a percentage basis, 37 fields increased in size, and only four fields decreased in size (Figure 6B). More than half of these fields (54%) increased in size by over 10%.

The group of giant U.S. oil fields having significant remaining potential has been buoyed by large recent increases (1/1/90 - 1/1/98) in field sizes (Figure 6B). These large field-size increases could be the result of high annual production rates; conversely, large field-size increases could drive annual production rates. Cause and effect are here complexly interwoven.

Field-Size Changes Measured as Barrels of Oil

Of the 209 giant U.S. oil fields in the data set of Table 2, the size of 29 fields (14%) increased or decreased by only 1 rnmbo or less between 1/1/90 and 1/1/98 (Figure 7A). Sixty- seven fields (32%) increased or decreased in size by 1 to 10 rnmbo in this eight-year period, 73 fields (35%) changed in size by 10 to 40 rnmbo, and 40 fields (19%) changed in size (larger or smaller) by more than 40 rnmbo. Changes in estimated total recovery of tens of millions of barrels were common for giant U.S. oil fields in the first eight years of the 1990's (Figure 7A).

The distribution of Figure 7 A is weighted toward the right, indicating that field-size increases have added substantially more oil than has been lost by field-size decreases. A number of giant U.S. oil fields have had extraordinarily long reserves lives and are declining at rates below expectations, largely because of the tendency for their estimated total recoveries to increase with time (Hatcher and Tussing, 1997).

The net change in estimated total recovery of the 209 giant U.S. oil fields contributing to Figure 7A (that is, the sum of the 209 individual field-size changes) is an increase of 5,896 rnmbo. This volume is equal to 2.5 years of U.S. oil production, assuming average daily production at the 1997 rate of 6.40 mmbo/day (Figure 1).

Of the 48 giant U.S. oil fields having significant remaining potential that are contributing to Figure 7B (a subset of the 59 fields of Table 3), 35 (73%) increased in size by more than 20 rnmbo in the first eight years of the 1990's. The net change in estimated total recovery of these 48 fields is an increase of 6,439 rnmbo (compared to a net increase of 5,896 rnmbo for the parent set of 209 giant fields).

As shown in Figure 7B, the size of two fields having significant remaining potential increased by more than 1,000 rnmbo between 1/1/90 and 1/1/98: these Alaskan fields are Prudhoe Bay (2,631 rnmbo) and Kuparuk River (1,094 rnmbo). The 12 fields of Figure 7B with field-size increases between 100 and 1,000 rnmbo ar° M^Tvay-Sunset (440 rnmbo, California), Wasson (288 rnmbo, Texas), Belridge S. (268 rnmbo, California), Spraberry Trend (201 rnmbo, Texas), Slaughter (176 rnmbo, Texas), Endicott (153 mmbo, Alaska), Seminole (148 mmbo, Texas), Levelland (130 mmbo, Texas), Rangely (117 mmbo, Colorado), Sho-Vel-Tum (115 mmbo, Oklahoma), Giddings (113 mmbo, Texas), and Cowden N. (111 mmbo, Texas). At the other extreme, East Texas field (Texas) decreased in size by 616 mmbo, and Elk Hills field (California) decreased by 65 mmbo.

Field-Size Changes by Location

Regional differences in patterns of field-size changes exist among the 209 giant U.S. oil fields of Table 2 (Figure 8). The giant fields of five areas had a net increase in estimated total recovery between 1/1/90 and 1/1/98, whereas the giant fields of four areas had a net decrease (Figure 8). The North Slope of Alaska provided the largest net increase, followed by the Permian Basin of West Texas and New Mexico, the San Joaquin Basin of southern California,

and basins of the Midcontinent. The Los Angeles Basin and coastal areas of California (area 5) showed a positive but relatively insignificant net change in estimated total recovery.

Each of the three areas that encompass the U.S. Gulf Coast (areas 6, 7, and 9) had net decreases in estimated total recovery of giant fields (Figure 8). The net change in area 9 would be negative even if the East Texas field (which decreased in size by 616 mmbo) were excluded. In the Rocky Mountains (area 8), only three of 19 giant fields decreased in size, but these decreases were large enough to place the area into the negative-change category.

Producing areas within the U.S. differ from one another with respect to factors affecting field-size changes, such as geologic characteristics, oil-field practices, and perhaps reserves- reporting patterns. Figure 8 illustrates how these differences can lead to very dissimilar regional perceptions of the volume of discovered but yet-to-be-produced oil in the U.S.

SUMMARY

1. In the U.S., a giant oil field is one whose size exceeds 100 mmbo. This study examines 293 giant fields (Table 1), using data as of 1/1/98. Recent changes in the sizes of 209 of these fields (Table 2) are also investigated, using production and reserves data as of 1/1/90.

2. Giant oil fields are still important to the U.S. energy picture (Figure 1). Average daily production in 1997 from giant fields was 3.65 mmbo/day (57% of total U.S. oil production), and remaining reserves were 11.3 bbo (50% of total U.S. remaining oil reserves).

3. Among the 293 giant U.S. oil fields, 59 fields account for 80% of total annual production (in 1997) and 80% of total remaining reserves (as of 1/1/98). These 59 fields (Table 3) are identified here as giant fields having significant remaining potential.

4. The field-size distribution of giant U.S. oil fields (Figure 4), which provides a possibleanalog for some less explored regions of the world, is highly skewed. One hundred and fifty- one fields have sizes between 100 and 200 mmbo, whereas only eight fields have sizes in the much larger range between 1,600 and 12,800 mmbo.

5. Although the median discovery year of giant U.S. oil fields is 1935, changes in field size (larger or smaller) of tens of millions of barrels were common between 1/1/90 and 1/1/98. The number of fields that increased in size outnumbered those that decreased in size by more than two to one (Figures 6, 7).

6. Changes in individual field sizes in the first eight years of the 1990's were highly variable. Some of this variability is related to regional location (Figure 8). Overall, the estimated total recovery of the 209 giant U.S. oil fields for which necessary data are available for analysis increased by 5,896 mmbo, equal to about 2.5 years of current U.S. oil production. The estimated total recovery of a subset of 48 giant fields having significant remaining potential increased by 6,439 mmbo.

REFERENCES CITED

Arrmgton, J.R., 1960, Predicting the size of crude reserves is key to evaluating exploration programs: Oil & Gas Journal, v.58, no. 9 (February 29), p. 130-134.

Artanasi, E.D., and Root, D.H., 1994, The enigma of oil and gas field growth: American Association of Petroleum Geologists Bulletin, v. 78, no. 3, p. 321-332.

Gautier, D.L., Dolton, G.L., Takahashi, K.I., and Varnes, K.L., eds., 1995, 1995 Nationalassessment of United States oil and gas resources - Results, methodology, and supporting data: U.S. Geological Survey Digital Data Series DDS-30.

Hatcher, D.B., and Tussing, A.R., 1997, Long reserves lives sustain prospects for independents in the U.S. lower 48: Oil & Gas Journal, v. 95, no. 46 (November 17), p. 49-59.

International Petroleum Encyclopedia, 1990, U.S. fields with reserves exceeding 100 million bbl (data table): Tulsa, OK, PennWell Publishing Co., 378 p.

International Petroleum Encyclopedia, 1998, U.S. fields with ultimate oil recovery exceeding 100 million bbl (data table): Tulsa, OK, PennWell Publishing Co., [CD-ROM].

Masters, C.D., Artanasi, E.D., and Root, D.H., 1994, World petroleum assessment and analysis: Proceedings of the 14th World Petroleum Congress, Chichester, England, John Wiley and Sons, v. 5, p. 529-541.

Schmoker, J.W., and Crovelli, R.A., 1998, A simplified spreadsheet program for estimating future growth of oil and gas reserves: Nonrenewable Resources, v. 7, no. 2, p. 149-155.

General

Number and estimated total oil recovery of all giant fields: 293 fields, 113.1 bbo Number and estimated total oil recovery of giant fields >1 bbo: 16 fields, 42.4 bbo Estimated total U.S. oil recovery: 195.6 bbo

Median discovery year of giant fields: 1935

Median size of giant fields: 194 mmbo Average size of giant fields: 386 mmbo

Annual and Cumulative Production

Average daily oil production in 1997 from all giant fields: 3.65 mmbo/day Average daily U.S. oil production in 1997: 6.40 mmbo/day Average daily U.S. oil consumption in 1996: 17.40 mmbo/day

Cumulative oil production from all giant fields: 101.8 bbo Cumulative U.S. oil production: 173.2 bbo

Remaining Reserves

Remaining (proved) oil reserves in all giant fields: 11.3 bbo Remaining (prove !) T. T S. oil reserves: 22.4 bbo

Median remaining oil reserves/annual oil production ratio of giant fields: 5.7 years Average remaining oil reserves/annual oil production ratio of giant fields: 8.3 years Average remaining U.S. oil reserves/annual U.S. oil production ratio: 9.6 years

Figure 1. Numerative overview of giant U.S. oil fields (fields larger than 100 mmbo) as of 1/1/98. Data are from Table 1 and International Petroleum Encyclopedia (1998). [mmbo = million barrels of oil. bbo = billion barrels of oil.]

100

50 100 150 200 250

GIANT-OIL-FIELD RANK BY ANNUAL PRODUCTION

300

B

;£UJ

O

50 100 150 200 250

GIANT-OIL-FIELD RANK BY REMAINING RESERVES

300

Figure 2. Cumulative percent of total annual production in 1997 (A) and of total remaining reserves as of 1/1/98 (B) for giant U.S. oil fields. Data are from Table 1.

New Mexico

Louisiana

California

Texas

10 15

NUMBER OF FIELDS

20

Figure 3. Locations of giant U.S. oil fields having significant remaining potential. These fields are defined and listed in Table 3.

100-200200-400400-800800-16001600-32003200-64006400-12800

FIELD-SIZE CATEGORY

2345

FIELD-SIZE CATEGORY

Figure 4. Number of fields (A) and volume of oil (estimated total recovery as of 1/1/98) (B) by field-size category, for giant U.S. oil fields. Data are from Table 1.

10

0!<LLJ

LU

O O CO

O

10 15 20 25»« - .~~---NUMBER OF FIELDS

30 35

Figure 5. Discovery year of giant U.S. oil fields for which production and reserves data as of 1/1/90 and 1/1/98 are available. Data are from Table 2.

11

UJ Li. LL. O

X. Ul CO

-69 -30 -25 -20 -15 -10 -6 -4 -2 -.5 .5 2 4 6 10 15 20 25 30 73

CHANGE IN FIELD SIZE (PERCENT)

B

CO 0

UJ LL. LL. O

QL LU CQ

-30 -25 -20 -15 -10 -6 -4 -2 -.5 .52 4 6 10 15 20 25 30 73

CHANGE IN FIELD SIZE (PERCENT)

Figure 6. Number of giant U.S. oil fields (A) and number of giant U.S. oil fields having significant remaining potential (B) by change in field size - measured in percent - from 1/1/90 to 1/1/98. Data are from Tables 2 and 3.

12

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-1000-100-40-20 -10-5-1 1 5 10 20 401001000 -2700 2700

CHANGE IN FIELD SIZE (MMBO)

Figure 7. Number of giant U.S. oil fields (A) and number of giant U.S. oil fields having significant remaining potential (B) by change in field size - measured in million barrels of oil - from 1/1/90 to 1/1/98. Data are from Tables 2 and 3.

13

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AREA DESCRIPTION NO. OF FIELDS

1 Alaska 8(1)2 West Texas (Dist. 8, 8A), New Mexico 39 (3)

3930 3 California - San Joaquin 19(9) ~+.,.*-+ > 4 Midcontinent - IL, KS, OK, TX (Dist. 10) 23(0)

-, 5 California - Coastal, L.A. Basin 24(16)~ 3 6 Southeast -AL.AR, FL, LA (N., S.), MS 34(8)

_ Jj 7 Louisiana - Offshore 17(9) mmmam s Rocky Mountains - CO, MT, ND, UT, WY 19(3)

^^B 9 E., SE. Texas (Dist. 2, 3, 4, 5, 6, 7C) 26(15)

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Figure 8. Net change in estimated total recovery from 1/1/90 to 1/1/98 by areas of the U.S., for giant U.S. oil fields. Data are from Table 2. Column for number of fields shows total number and number that declined in size (in parenthesis).

14

Table 1. U.S. oil fields having estimated total recovery exceeding 100 million barrels of oil (mmbo). [Data are from International Petroleum Encydopedia (1998). Production and reserves are in mmbo. Estimated total recovery = cumulative production plus remaining reserves. Res./Prod. = ratio of remaining reserves to 1997 production.]

Field Location Discovery Production Cum. Production Rem. Reserves Est. Total Recovery Res./Prod. Year in 1997 as of 1/1/98 as of 1/1/98 as of 1/1/98 (years)

1 Citronelle2 Endicott3 Granite Point4 Kuparuk River5 Lisburne6 McArthur River7 Mid. Ground Shoal8 Milne Point9 Point Mclntyre

10 Prudhoe Bay1 1 Swans on River12 Magnolia13 Smackover14 Belridge N.15 Belridge S.16 Buena Vista17 Coalinga1 8 Coalinga Nose19 Coles Levee N.20 Cuyama S.21 Cymric22 Edison23 Elk Hills24 Fruitvale25 Greeley26 Kern Front27 Kern River28 Kettleman N. Dome29 Lost Hills30 Midway-Sunset31 Mount Poso32 Rio Bravo33 Round Mountain34 Yowlumne35 Carpinteria36 Cat Canyon E., W.37 Dos Cuadras38 Hondo39 Orcutt40 Pescado41 Point Arguello42 Rincon43 San Ardo44 Santa Maria Valley45 South Mountain46 Ventura47 Beta48 Beverly Hills49 Brea-Olinda50 Coyote E.51 Dominguez52 Huntington Beach53 Inglewood54 Long Beach55 Montebello56 Richfield57 San Miguelito

AlabamaAlaskaAlaskaAlaskaAlaskaAlaskaAlaskaAlaskaAlaskaAlaskaAlaskaArkansasArkansasCal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-San Joaq.Cal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-CoastalCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. BasinCal.-L.A. Basin

195519781965196919671965196219691988196819571938192219121911190918901938193819491909192819111928193619121899192819101894192619371927197419661908196919691901196919811927194719341916191919761900188019091923192019241921191719191931

1.15721.000

2.00096.000

3.0005.0002.000

19.00059.000

251.0001.0000.3301.5701.649

42.8480.8869.7320.2330.2250.254

13.8470.816

20.5290.4710.1582.047

48.7460.113

11.52060.692

1.0750.0390.2731.1010.7680.9192.712

16.49 r0.766

15.16110.563

1.0064.6290.3820.7305.1913.0091.3951.3820.3810.3483.6822.4571.6830.2710.3990.967

159.4358.0130.0

1484.0119.0586.0178.685.0

212.09507.0

224.4165.8574.4106.4

1108.6659.2849.3503.9163.1221.5294.2141.8

1119.3120.2114.4193.3

1618.8458.0266.2

2360.1291.5116.698.7

106.299.0

298.0241.8

- 157.8172.557.4

123.2156.4447.2204.2152.4945.3

73.0135.5398.4112.7273.7

1099.5365.6926.0195.7197.6109.6

4.4170.0

16.01111.0

32.044.012.0

223.0241.0

3042.011.02.64.7

10.1272.3

18.557.14.51.63.5

68.64.6

288.65.90.8

23.6329.0

2.351.9

332.730.4

0.32.1

11.09.7

22.015.0

121.45.5

51.7160.7

3.682.814.44.6

66.8140.5

12.140.3

9.13.1

38.626.718.6

6.35.3

28.4

163.8528.0146.0

2595.0151.0630.0190.6308.0453.0

12549.0235.4168.4579.1116.5

1380.9677.7906.4508.4164.7225.0362.8146.4

1407.9126.1115.2216.9

1947.8460.3318.1

2692.8321.9116.9100.8117.2108.7320.0256.8279.2178.0109.1283.9160.0530.0218.6157.0

1012.1213.5147.6438.7121.8276.8

1138.1392.3944.6202.0202.9138.0

3.88.18.0

11.610.78.86.0

11.74.1

12.111.07.93.06.16.4

20.95.9

19.37.1

13.85.05.6

14.112.5

5.111.56.7

20.44.55.5

28.37.77-7

10.012.623.9

5.57.47.23.4

15.23.6

17.937.76.3

12.946.7

8.729.223.9

8.910.510.911.123.213.329.4

15 Table 1

Field Location Discovery Production Cum. Production Rem. Reserves Est. Total Recovery Res./Prod. Year in 1997 as of 1/1/98 as of 1/1/98 as of 1/1/98 (years)

58 Santa Fe Springs Cal.-LA. Basin59 Seal Beach Cal.-L.A. Basin60 Torrance Cal.-L.A. Basin61 Yorba Linda Cal.-L.A. Basin62 Wilmington Cal.-L.A. Basin63 Rangely Colorado64 Jay Florida65 Clay City Illinois66 Dale Consolidated Illinois67 Lawrence Illinois68 Louden Illinois69 Main Illinois70 New Harmony Illinois71 Salem Illinois72 Bemis-Shutts Kansas73 Chase-Silica Kansas74 El Dorado Kansas75 Hall-Gurney Kansas76 Kraft-Prusa Kansas77 Trapp Kansas78 Bay Marchand 2 Louisiana-Off.79 Breton Sound 20 Louisiana-Off.80 Eugene Island 126 Louisiana-Off.81 Eugene Island 175 Louisiana-Off.82 Eugene Island 276 Louisiana-Off.83 Eugene Island 330 Louisiana-Off.84 Garden Banks 426 Louisiana-Off.85 Grand Isle 16 Louisiana-Off.86 Grand Isle 43 Louisiana-Off.87 Grand Isle 47 Louisiana-Off.88 Green Canyon 65 Louisiana-Off.89 Main Pass 35 Louisiana-Off.90 Main Pass 41 Louisiana-Off.91 Main Pass 69 Louisiana-Off.92 Main Pass 144 Louisiana-Off.93 Main Pass 299 Louisiana-Off.94 Main Pass 306 Louisiana-Off.95 Main Pass 31 1 Louisiana-Off.96 Miss. Canyon 194 Louisiana-Off.97 Ship Shoal 1 1 3 Louisiana-Off.98 Ship Shoal 207 Louisiana-Off.99 Ship Shoal 208 Louisiana-Off.

100 S. Marsh Island 128 Louisiana-Off.101 South Pass 24 Louisiana-Off.102 South Pass 27 Louisiana-Off.103 South Pass 61 Louisiana-Off.104 South Pass 62 Louisiana-Off.105 South Pass 65 Louisiana-Off.106 South Pass 89 Louisiana-Off.107 S. Timbalier21 Louisiana-Off.108 West Delta 30 Louisiana-Off.1 09 West Delta 73 Louisiana-Off.1 1 0 West Delta 79 Louisiana-Off.1 1 1 Avery Island Louisiana-S.112 Bay de Chene Louisiana-S.113 Bay St. Elaine Louisiana-S.114 Bayou Sale Louisiana-S.1 1 5 Black Bay W. Louisiana-S.116 Caillou Island Louisiana-S.117 Cote Blanche Bay W. Louisiana-S.118 Cote Blanche Island Louisiana-S.

1919192419221930193219331970193819401906193819061938193819281931191719311937193719491953195019561964193019871948195619551984195119571948196719621969197719801955196719621974195019541968196519651969193919491962196619421941192819411953193019401948

0.7320.5160.7890.449

19.7797.5293.7770.9750.0771.7430.8851.0540.6190.9391.0240.6650.7120.6870.3510.6655.3112.0020.6893.2961.8098.655

22.7062.6592.8841.4127.1330.4503.8411.9591.6146.9030.9792.8603.2132.0190.5102.1 ?u1.4054.8502.4027.9142.1881.4407.2901.6434.7793.8030.8440.6110.3310.2220.3371.2142.8820.3181.315

619.9208.9220.9

91.12497.3

833.6395.4409.8105.5414.8396.6246.8160.3234.9254.2309.4306.0154.0131.6234.2695.2114.2122.695.489.1

341.373.1

285.9302.8

94.693.599.4

258.5261.9113.7109.2212.4

76.6161.0100.494.8

184.1114.3284.7152.1203.1127.9121.0154.1234.5496.8230.4148.0100.0

99.1167.5165.4159.6625.3188.2188.5

12.87.6

18.010.2

290.970.423.1

6.30.75.33.65.83.12.96.23.04.13.82.23.6

40.98.85.1

15.915.647.593.418.448.121.846.5

3.817.713.012.445.1

5.427.259.024.1

6.012.78.9

27.913.429.212.5

9.241.6

8.429.649.611.0

2.62.31.01.34.6

16.42.85.3

632.7216.5238.9101.3

2788.2904.0418.5416.1106.2420.1400.2252.6163.4237.8260.4312.4310.1157.8133.8237.8736.1123.0127.7111.3104.7388.8166.5304.3350.9116.4140.0103.2276.2274.9126.1154.3217.8103.8220.0124.5100.8196.8123.2312.6165.5232.3140.4130.2195.7242.9526.4280.0159.0102.6101.4168.5166.7164.2641.7191.0193.8

17.514.722.822.714.79.46.16.58.43.04.15.55.03.16.14.55.85.56.35.47.74.47.44.88.65.54.16.9

16.715.46.58.44.66.67.76.55.59.5

18.411.911.85.96.35.85.63.75.76.45.75.16.2

13.013.04.36.94.53.93.85.78.84.0

16 Table 1

Field

119 Delta Farms120 Garden Island Bay121 Golden Meadow122 Grand Bay123 HackberryE.124 HackberryW.125 Iberia126 Jennings127 Lafitte128 LakeBarre129 Lake Washington130 Leeville131 Quarantine Bay132 Romere Pass133 Timbalier Bay onsh.134 Venice135 Vinton136 Weeks Island137 West Bay138 White Castle139 Caddo-Pine Island140 Delhi141 Haynesville142 Homer143 Nebo-Hemphill144 Rodessa145 Baxterville146 Heidelberg147 Tinsley148 Cabin Creek149 Cut Bank150 Elk Basin151 Pennel

152 Pine153 Blinebry-Drinkard154 Denton155 Empire-Abo156 Eunice-Monument157 Grayburg-Jackson158 Hobbs159 Langiie-Mattix160 Maljamar161 Vacuum162 Beaver Lodge163 Bowlegs164 Burbank165 Cement166 Gushing167 Earlsboro168 Eola-Robberson169 Fitts170 Glen Pool171 Golden Trend172 Healdton173 Hewitt174 Little River175 Oklahoma City176 Postle177 Seminole178 Sho-Vel-Tum179 Sooner Trend

Location Discovery Production Cum. Production Rem. Reserves Est. Total Recovery Res./Prod. Year in 1997 as of 1/1/98 as of 1/1/98 as of 1/1/98 (years)

Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-S.Louisiana-N.Louisiana-N.Louisiana-N.Louisiana-N.Louisiana-N.Louisiana-N.MississippiMississippiMississippiMontanaMontanaMontanaMontanaMontanaNew MexicoNew MexicoNew MexicoNew MexicoNew MexicoNew MexicoNew Mexicoi^..- MexicoNew MexicoN. DakotaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahomaOklahoma

1944193419381938192719281917190119351929193119311937195019381937191019451940192919051944192119191940193519441944193919531926191519551951194519491957192919291928193519261929195119271920191719121926192119331905194519131919192719281960192619191965

0.2711.1070.3200.5590.3170.3980.2350.1370.6332.0951.6940.3130.8880.3010.7950.2000.1723.0110.9030.2271.8990.0330.6300.2861.5510.2110.9371.9960.3381.2140.4590.4441.9050.7570.9590.5190.5562.3874.0592.9490.9441.5358.0150.9880.0710.6721.0771.0370.0870.3741.8200.4132.3661.2791.6180.0890.4181.4890.125

10.8002.714

120.3230.7139.0177.4112.7148.899.9

118.2264.7214.8260.2145.9179.9100.9306.6186.1163.4246.3237.1

93.5383.6213.5177.6101.4102.8109.1252.2196.0224.8102.2168.2100.195.5

113.7142.2145.2228.3147.4118.5339.4135.1158.6508.5123.5163.7543.7143.1508.6203.5139.9219.6333.9502.3348.7285.7142.5823.3115.9195.0

1298.2327.6

2.23.81.22.04.02.10.81.23.5

11.96.73.06.21.6

12.63.41.8

13.07.56.6

10.92.93.81.38.71.45.25.61.36.82.01.3

11.43.34.12.12.96.6

18.317.74.67.3

31.25.11.12.85.95.80.81.58.34.6

21.04.25.41.85.86.41.0

52.116.9

122.5234.5140.2179.4116.7150.9100.7119.4268.2226.7266.9148.9186.1102.5319.2189.5165.2259.3244.6100.1394.5216.4181.4102.7111.5110.5257.4201.6226.1109.0170.2101.4106.9117.0146.3147.3231.2154.0136.8357.1139.7165.9539.7128.6164.8546.5149.0514.4204.3141.4227.9338.5523.3352.9291.1144.3829.1122.3196.0

1350.3344.5

8.13.43.83.6

12.65.33.48.85.55.74.09.67.05.3

15.817.010.54.38.3

29.15.7

87.96.04.55.66.65.52.83.85.64.42.96.04.44.34.05.22.84.56.04.94.83.95.2

15.54.25.55.69.24.04.6

11.18.93.33.3

20.213.94.38.04.86.2

17 Table 1

Field Location Discovery Production Cum. Production Rem. Reserves Est. Total Recovery Res./Prod. Year in 1997 as of 1/1/98 as of 1/1/98 as of 1/1/98 (years)

180 St. Louis181 Darst Creek182 Luling-Branyon183 Pearsall184 Greta185 Lake Pasture186 TomO'Connor187 West Ranch188 Anahuac189 Barbers Hill190 Con roe191 Giddings192 Goose Creek193 Hastings E.194 High Island195 Hull196 Humble197 Magnet Withers198 Manvel199 Oyster Bayou200 Raccoon Bend201 Sour Lake202 Thompson203 Tomball204 Webster205 W. Columbia206 Agua Dulce-Stratton207 Borregos208 Kelsey209 Plymouth210 Seeligson211 TCB212 White Point E.213 Van214 East Texas215 Fairway216 Hawkins217 Neches218 Quitman 219Talco220 Stephens Cnty Reg.221 Big Lake222 McCamey223 Pegasus224 Andector225 Block 31226 Cowden N.227 Cowden S.-Foster-J228 Dollarhide229 Dune230 Fuhrman-Mascho231 Fullerton232 Goldsmith233 Hendrick234 Howard-Glasscock235 latan E.236 Jordan237 Kermit238 Keystone239 Mabee240 McElroy

OklahomaTexas-Dist. 1Texas-Dist. 1Texas-Dist. 1Texas-Dist. 2Texas-Dist. 2Texas-Dist. 2Texas-Dist. 2Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 3Texas-Dist. 4Texas-Dist. 4Texas-Dist. 4Texas-Dist. 4Texas-Dist. 4Texas-Dist. 4Texas-Dist. 4Texas-Dist. 5Texas-Dist. 6Texas-Dist. 6Texas-Dist. 6Texas-Dist. 6Texas-Dist. 6Texas-Dist. 6Texas-Dist. 7BTexas-Dist. 7CTexas-Dist. 7CTexas-Dist. 7CTexas-Dist. 8Texas-Dist. 8Texas-Dist. 8

I. Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8

1925192919221936193319531934193819351916193119711906193419221918190519361931194119271902192119331937191719281945193819251925194419381928193019601940195319481931191619231925194919461945193019301945193819301942193419261925192619371928193019431926

0.3880.5510.9291.8050.2770.9502.8950.7890.1530.1851.160

16.5900.4881.0611.0620.4110.2150.9160.3150.3390.3690.4941.1020.1881.9250.1500.2120.0310.0520.0750.0810.0400.0221.559

19.2131.8253.1580.4310.6050.8333?98

0.3730.1300.8140.4651.1149.5955.0152.8801.1491.2016.6554.1980.3574.2152.1370.6110.2711.4142.4407.455

181.1159.2155.7153.3150.9100.1787.7391.9288.2113.5742.4457.0122.9707.0140.3171.7

99.7121.3103.5164.6104.8102.7487.9123.1596.2102.5148.3114.9116.1124.2272.8113.6104.7541.7

5271.4210.1865.2110.1129.6284.9172.7133.6126.3143.4186.3238.6598.3560.9219.0199.4117.1412.1799.3256.4447.9165.3135.5116.5325.7108.1540.1

1.43.13.4

29.71.63.9

15.15.21.20.84.9

66.91.83.23.02.21.15.51.41.51.57.05.71.09.22.01.40.60.81.90.70.60.68.3

110.212.820.4

1.62.76.5

15.71.40.73.72.47.8

50.528.417.86.33.2

35.226.9

1.820.812.73.01.65.5

13.736.4

182.5162.3159.1183.0152.5104.0802.8397.1289.4114.3747.3523.9124.7710.2143.3173.9100.8126.8104.9166.1106.3109.7493.6124.1605.4104.5149.7115.5116.9126.1273.5114.2105.3550.0

5381.6222.9885.6111.7132.3291.4188.4135.0127.0147.1188.7246.4648.8589.3236.8205.7120.3447.3826.2258.2468.7178.0138.5118.1331.2121.8576.5

3.65.63.7

16.55.84.15.26.67.84.34.24.03.73.02.85.45.16.04.44.44.1

14.25.25.34.8

13.36.6

19.415.425.3

8.615.027.3

5.35.77.06.53.74.57.84.83.85.44.55.27.05.35.76.25.52.75.36.45.04.95.94.95.93.95.64.9

18 Table 1

Field

241 Means242 Midland Farms243 Penwell244 Sand Hills245 Shatter Lake246 Spraberry Trend247 TXL248 Waddell249 Ward S.250 Ward Estes N.251 Westbrook252 Yates253 Adair254 Anton-lrish255 Cedar Lake256 Cogdell257 Diamond M258 G'arza259 Jo-Mill260 Kelly-Snyder261 Levelland262 Prentice263 Robertson N.264 Salt Creek265 Seminole266 Sharon Ridge267 Slaughter268 Wasson269 Welch270 Archer Cnty Reg.271 Cooke Cnty Reg.272 K-M-A273 Walnut Bend274 Wichita Cnty Reg.275 Wilbarger Cnty Reg.276 Young Cnty Reg.277 Panhandle278 Altamont279 Bluebell280 Greater Aneth281 Byron282 Elk Basin283 Frannie284 Garland285 Grass Creek286 Hamilton Dome287 Hartzog Draw288 Lance Creek289 Little Buffalo Basin290 Lost Soldier291 Oregon Basin292 Salt Creek293 Wertz

Location Discovery Production Cum. Production Rem. Reserves Est. Total Recovery Res./Prod. . Year in 1997 as of 1/1/98 as of 1/1/98 as of 1/1/98 (years)

Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8Texas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 8ATexas-Dist. 9Texas-Dist. 9Texas-Dist. 9Texas-Dist. 9Texas-Dist. 9Texas-Dist. 9Texas-Dist. 9Texas-Dist. 1 0UtahUtahUtahWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyomingWyoming

SUMS

19341944192619311947195119441927193819291920192619471944193919491948192619531948193819511956195019361923193619361942191119261931193819101915191719211955194919561918191519281906191419181976191819141916191218891921

4.2131.4881.5852.2101.415

23.4142.2951.0550.3562.4051.278

20.3100.8221.5272.6950.4910.9822.0752.3953.145

11.0803.1055.1029.191

11.9501.502

15.50327.410

2.3510.9420.6870.8330.3691.8550.4110.8705.1251.6132.7725.8740.6271.8050.2852.0221.4501.7782.1110.1250.7972.4574.4312.1590.509

1330.916

275.6261.0122.4268.0106.2816.0276.9106.8109.1391.1103.0

1356.1115.7196.496.4

299.7251.7127.2147.7

1295.5615.7198.6113.4331.5656.3100.6

1177.91964.1

167.7189.8107.6147.6127.1354.0150.4107.4

1475.8112.2140.9405.0127.4452.1120.3182.9201.4249.5

96.5109.1131.3237.2441.8658.6113.4

101758.7

25.37.67.8

13.04.9

95.911.23.61.5

23.56.6

598.42.4

10.115.3

3.76.09.1

11.454.548.624.528.946.457.510.677.9

122.520.1

5.43.22.61.99.62.32.4

31.115.915.925.0

2.412.0

1.37.75.65.8

12.10.93.0

19.119.617.58.7

11303.9

300.9268.6130.2281.0111.1911.9288.1110.4110.6414.6109.6

1954.5118.1206.5111.7303.4257.7136.3159.1

1350.0664.3223.1142.3377.9713.8111.2

1255.82086.6

187.8195.2110.8150.2129.0363.6152.7109.8

1506.9128.1156.8430.0129.8464.1121.6190.6207.0255.3108.6110.0134.3256.3461.4676.1122.1

113062.6

6.05.14.95.93.54.14.93.44.29.85.2

29.52.96.65.77.56.14.44.8

17.34.47.95.75.04.87.15.04.58.55.74.73.15.15.25.62.86.19.95.74.33.86.64.63.83.93.35.77.23.87.84.48.1

17.1

8.3(ave)

19 Table 1

Tab

le 2. G

iant U

.S. o

il fields o

f Tab

le 1 for w

hich

pro

du

ction

and

reserves as of 1/1/90 are availab

le. [D

ata as of 1/1/98 are repeated from

Table 1.

Data as o

f 1/1/90 are from

International Petroleum

Encyclopedia (1990).

Production and reserves are in m

mbo.

Estim

ated total recovery = cumulative production plus rem

aining reserves.]

Field

1 C

itronelle2 E

ndicott3 G

ranite Point

4 Kuparuk R

iver5 Lisburne6 M

cArthur R

iver7 M

id. Ground S

hoal8 P

rudhoe Bay

9 Sw

anson River

10 Sm

ackover11

BelridgeS

.12 B

uena Vista

13 Coalinga

14 Coalinga N

ose15 C

oles Levee N.

16 Cuyam

a S.17 C

ymric

18 Edison

19 Elk H

ills20 F

ruitvale21

Greeley

22 Kern F

ront23 K

ern River

24 Kettlem

an N. D

ome

25 Lost Hills

26 Midw

ay-Sunset

27 Mount P

oso28 R

io Bravo

29 Yow

lumne

30 Carpinteria

31 Cat C

anyon E.. W

.32 D

os Cuadras

33 Hondo

34 Orcutt

35 Rincon

36 San A

rdo37 S

anta Maria V

alley38 S

outh Mountain

39 Ventura

40 Beta

Location D

iscovery C

um. P

roduction Rem

. Reserves E

st. Total R

ecovery Cum

. Production R

em. R

eserves Est. T

otal Recovery

Change in E

st. Y

ear as o

f 1/1/90 as of 1/1/90

as of 1/1/90

as of 1/1/98 as of 1/1/98

as of 1/1/98

Total Recovery

Alabam

aA

laskaA

laskaA

laskaA

laskaA

laskaA

laskaA

laskaA

laskaA

rkansasC

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-S

an Joaq.C

al.-San Joaq.

Cal.-C

oastalC

al.-Coastal

Cal.-C

oastalC

al.-Coastal

Cal.-C

oastalC

al.-Coastal

Cal.-C

oastalC

al.-Coastal

Cal.-C

oastalC

al.-Coastal

Cal.-L.A

. Basin

1955197819651969196719651962196819571922191119091890193819381949190919281911192819361912189919281910189419261937197419661908196919691901192719471934191619191976

149.682.1

111.9616.1

49.4535.8158.6

6733.2211.3559.7737.3648.8764.1499.8160.9218.7209.1135.7927.7116.1112.8174.5

1253.0456.8183.9

1938.8269.5116.287.490.3

290.4216.9

99.5166.7149.9411.9199.6146.7901.5

46.0

5.2293.0

17.0885.0161.040.0

8.03185.0

8.08.0

375.136.7

151.08.32.36.5

85.231.4

545.513.2

1.653.8

694.51.1

66.7314.4

73.11.2

21.027.144.850.0

102.49.4

13.7119.338.911.390.2

168.3

154.8375.1128.9

1501.1210.4575.8166.6

9918.2219.3567.7

1112.4685.5915.1508.1163.2225.2294.3167.1

1473.2129.3114.4228.3

1947.5457.9250.6

2253.2342.6117.4108.4117.4335.2266.9201.9176.1163.6531.2238.5158.0991.7214.3

159.4358.0130.0

1484.0119.0586.0178.6

9507.0224.4574.4

1108.6659.2849.3503.9163.1221.5294.2141.8

1119.3120.2114.4193.3

1618.8458.0266.2

2360.1291.5116.6106.299.0

298.0241.8157.8172.5156.4447.2204.2152.4945.3

73.0

4.4170.0

16.01111.0

32.044.012.0

3042.011.04.7

272.318.557.1

4.51.63.5

68.64.6

288.65.90.8

23.6329.0

2.351.9

332.730.4

0.311.09.7

22.015.0

121.45.53.6

82.814.44.6

66.8140.5

163.8528.0146.0

2595.0151.0630.0190.6

12549.0235.4579.1

1380.9677.7906.4508.4164.7225.0362.8146.4

1407.9126.1115.2216.9

1947.8460.3318.1

2692.8321.9116.9117.2108.7320.0256.8279.2178.0160.0530.0218.6157.0

1012.1213.5

9.0152.9

17.11093.9

-59.454.224.0

2630.816.1'11.4

268.5-7.8-8.70.31.5

-0.2

68.5-20.7-65.3-3.20.8

-11.40.32.4

. 67.5

439.6-20.7

-0.58.8

-8.7-15.2-10.177.3

1.9-3.6-1.2

-19.9-1.020.4-0.8

20T

able 2

Field

41 Beverly H

ills42 B

rea-Olinda

43 Coyote E.

44 Dom

inguez45 H

untington Beach

46 Inglewood

47 Long Beach

48 Montebello

49 Richfield

50 Santa Fe S

prings51 S

eal Beach

52 Torrance53 W

ilmington

54 Rangely

55 Jay56 C

lay City

57 Lawrence

58 Louden59 M

ain60 N

ew H

armony

61 Salem

62 Bem

is-Shutts

63 Chase-S

ilica64 El D

orado65 H

all-Gurney

66 Trapp67 B

ay Marchand 2

68 Eugene Island 330

69 Grand Isle 16

70 Grand Isle 43

71 Main P

ass 4172 M

ain Pass 306

73 Miss. C

anyon 19474 S

hip Shoal 207

75 Ship S

hoal 20876 S. M

arsh Island 12877 S

outh Pass 27

78 South P

ass 6179 S

outh Pass 62

80 South P

ass 6581 S. Tim

balier 2182 W

est Delta 30

83 West D

elta 73

Location D

iscovery C

um. P

roduction Rem

. Reserves Est. Total R

ecovery Cum

. Production R

em. R

eserves Est. Total Recovery C

hange in Est. Y

ear as of 1/1/90

as of 1/1/90 as of 1/1/90

as of 1/1/98 as of 1/1/98

as of 1/1/98 Total R

ecovery

Cal.-L.A

. Basin

Cal.-L

A B

asinC

al.-L

A Basin

Cal.-L.A

. Basin

Cal.-L.A

. BasinC

al.-L.A. Basin

Cal.-L.A

. BasinC

al.-L.A. B

asinC

al.-L.A. Basin

Cal.-L.A

. Basin

Cal.-L.A

. Basin

Cal.-L.A

. Basin

Cal.-L.A

. BasinC

oloradoFloridaIllinoisIllinoisIllinoisIllinoisIllinoisIllinoisK

ansasK

ansasK

ansasK

ansasK

ansasLouisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.Louisiana-O

ff.

1900188019091923192019241921191719191919192419221932193319701938190619381906193819381928193119171931193719491930194819561957196919801967196219741954196819651965193919491962

124.4386.1109.2269.8

1071.5348.2912.0193.0190.6614.0203.9213.6

2318.9751.7365.4396.1397.3389.5235.3154.5227.4245.2303.0299.4147.1227.4606.3277.7267.3277.4240.8203.6121.488.6

163.781.0

131.8160.4108.6104.8218.3451.8192.8

40.552.612.76.9

66.951.415.09.7

26.08.1

13.334.3

469.035.051.26.05.02.85.03.83.53.43.61.83.13.6

50.047.382.080.520.476.671.837.261.720.068.940.079.485.345.141.782.2

164.9438.7121.9276.7

1138.4399.6927.0202.7216.6622.1217.2247.9

2787.9786.7416.6402.1402.3392.3240.3158.3230.9248.6306.6301.2150.2231.0656.3325.0349.3357.9261.2280.2193.2125.8225.4101.0200.7200.4188.0190.1263.4493.5275.0

135.5398.4112.7273.7

1099.5365.6926.0195.7197.6619.9208.9220.9

2497.3833.6395.4409.8

414.8396.6246.8160.3234.9254.2309.4306.0154.0234.2695.2341.3285.9302.8258.5212.4161.094.8

184.1114.3152.1203.1127.9121.0234.5496.8230.4

12.140.3

9.13.1

38.626.718.66.35.3

12.87.6

18.0290.970.423.16.35.33.65.83.12.96.23.04.13.83.6

40.947.518.448.117.75.4

59.06.0

12.78.9

13.429.212.59.28.4

29.649.6

147.6438.7121.8276.8

1138.1392.3944.6202.0202.9632.7216.5238.9

2788.2904.0418.5416.1420.1400.2252.6163.4237.8260.4312.4310.1157.8237.8736.1388.8304.3350.9276.2217.8220.0100.8196.8123.2165.5232.3140.4130.2242.9526.4280.0

-17.30.0

-0.1

0.1-0.3-7.3

17.6-0.7

-13.710.6-0.7-9

.0

0.3117.3

1.914.017.87.9

12.35.16.9

11.85.88.97.66.8

79.8,

63.8-45.0

-7.0

15.0-62.426.8

-25.0-2

8.6

22.2-35.231.9

-47.6-59.9-20.532.9

5.0

21Table 2

Field

84 Bay de C

hene85 B

ay St. E

laine86 B

ayou Sale

87 Black B

ay W.

88 Caillou Island

89 Cote B

lanche Bay W

.90 D

elta Farm

s91

Garden Island B

ay92 G

olden Meadow

93 Grand B

ay94 H

ackberry E.95 H

ackberry W.

96 Jennings97 Lafffle98 Lake B

arre99 Lake W

ashington100 Leeville101

Quarantine B

ay102 T

imbalier B

ay onsh.103 V

enice104 V

inton105 W

eeks Island106 W

est Bay

107 Caddo-P

ine Island108 D

elhi109 H

aynesville110 H

omer

111 R

odessa112 B

axterville113 H

eidelberg114 T

insley115 C

ut Bank

116 Pine

117 Denton

118 Em

pire-Abo

119 Eunice-M

onument

120 Hobbs

121 M

aljamar

122 Vacuum

123 Beaver Lodge124 Burbank125 E

ola-Robberson

126 Fitts

Location D

iscovery C

um. P

roduction Rem

. Reserves E

st. Total R

ecovery Cum

. Production R

em. R

eserves Est. T

otal Recovery C

hange in Est.

Year

as of 1/1/90 as of 1/1/90

as of 1/1/90 as of 1/1/98

as of 1/1/98 as of 1/1/98

Total Recovery

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-S.

Louisiana-N.

Louisiana-N.

Louisiana-N.

Louisiana-N.

Louisiana-N.

Mississippi

Mississippi

Mississippi

Montana

Montana

New

Mexico

New

Mexico

New

Mexico

New

Mexico

New

Mexico

New

Mexico

N. D

akotaO

klahoma

Oklahom

aO

klahoma

1941192819411953193019401944193419381938192719281901193519291931193119371938193719101945194019051944192119191935194419441939192619511949195719291928192619291951192019211933

96.8165.3162.1147.0604.7183.0115.7222.4136.1170.9109.5143.4116.6256.6205.1245.0142.2173.4297.2182.8161.3227.0229.5364.2212.3169.198.8

106.4241.4177.2220.3163.1106.4139.6221.6128.3304.4146.8442.8113.0537.6134.0202.4

17.524.82.68.3

71.545.0

6.730.8

3.63.47.15.00.58.2

19.013.76.7

15.023.26.70.5

20.315.110.034.1

1.51.51.18.29.72.5

36.44.42.1

48.48.0

20.03.3

40.015.27.57.49.5

114.3190.1164.7155.3676.2228.0122.4253.2139.7174.3116.6148.4117.1264.8224.1258.7148.9188.4320.4189.5161.8247.3244.6374.2246.4170.6100.3107.5249.6186.9222.8199.5110.8141.7270.0136.3324.4150.1482.8128.2545.1141.4211.9

99.1167.5165.4159.6625.3188.2120.3230.7139.0177.4112.7148.8118.2264.7214.8260.2145.9179.9306.6186.1163.4246.3237.1383.6213.5177.6101.4109.1252.2196.0224.8168.2113.7145.2228.3147.4339.4158.6508.5123.5543.7139.9219.6

2.31.01.34.6

16.42.82.23.81.22.04.02.11.23.5

11.96.73.06.2

12.63.41.8

13.07.5

10.92.93.81.31.45.25.61.32.03.32.12.96.6

17.77.3

31.25.12.81.58.3

101.4168.5166.7164.2641.7191.0122.5234.5140.2179.4116.7150.9119.4268.2226.7266.9148.9186.1319.2189.5165.2259.3244.6394.5216.4181.4102.7110.5257.4201.6226.1170.2117.0147.3231.2154.0357.1165.9539.7128.6546.5141.4227.9

-12.9-21.6

2.08.9

-34.5-37.0

0.1-18.7

0.55.10.12.52.33.42.68.20.0

-2.3-1.2

0.03.4

12.00.0

20.3-30.010.82.4

. 3.07.8

14.73.3

-29.36.25.6

-38.817.732.715.856.9

0.41.40.0

16.0

22T

able 2

Field

127 Glen P

ool128 G

olden Trend

129 Healdton

130 Hew

itt131 O

klahoma C

ity132 P

ostle133 S

ho-Vel-T

um134 S

ooner Trend

135 Greta

136 Lake Pasture

137 Tom

O'C

onnor138 W

est Ranch

139 Anahuac

140 Conroe

141 G

iddings142 M

agnet Withers

143 Oyster B

ayou144 T

hompson

145 Tom

ball146 W

ebster147 A

gua Dulce-S

tratton148 B

orregos149 K

elsey150 P

lymouth

151 S

eeligson152 TC

B153 W

hite Point E.

154 Van

155 East T

exas156 Fairw

ay157 H

awkins

158 Neches

159 Quitm

an160 B

ig Lake161 A

ndector162 B

lock 31163 C

owden N

.164 C

owden S

.-Foster-J.

165 Dollarhide

166 Dune

167 Fullerton168 G

oldsmith

169 How

ard-Glasscock

Location D

iscovery C

um. P

roduction Rem

. Reserves E

st. Total R

ecovery Cum

. Production R

em. R

eserves Est. T

otal Recovery C

hange in Est.

Year

as of 1/1/90 as of 1/1/90

as of 1/1/90 as of 1/1/98

as of 1/1/98

as of 1/1/98 T

otal Recovery

Oklahom

aO

klahoma

Oklahom

aO

klahoma

Oklahom

aO

klahoma

Oklahom

aO

klahoma

Texas-D

ist. 2T

exas-Dist. 2

Texas-D

ist. 2T

exas-Dist. 2

Texas-D

ist. 3T

exas-Dist. 3

Texas-D

ist. 3T

exas-Dist. 3

Texas-D

ist. 3T

exas-Dist. 3

Texas-D

ist. 3T

exas-Dist. 3

Texas-D

ist. 4T

exas-Dist. 4

Texas-D

ist. 4T

exas-Dist. 4

Texas-D

ist. 4T

exas-Dist. 4

Texas-D

ist. 4T

exas-Dist. 5

Texas-D

ist. 6T

exas-Dist. 6

Texas-D

ist. 6T

exas-Dist. 6

Texas-D

ist. 6T

exas-Dist. 7C

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8

1905194519131919192819601919196519331953193419381935193119711936194119211933193719281945193819251925194419381928193019601940195319481923194619451930193019451938194219341925

328.8477.8336.4270.4817.1107.5

1184.3299.4148.189.5

754.3382.2285.6730.0270.8112.4160.9476.1121.4577.2147.0114.2115.1123.1271.7113.0104.1524.7

5044.0194.8828.4105.0122.6130.4182.5223.1501.6509.5196.3185.3355.4762.0409.1

4.125.0

7.812.05.0

13.851.016.112.010.948.6

8.514.431.0

140.33.5

17.423.8

9.616.024.420.036.0

3.155.352.2

6.212.2

953.515.735.6

5.17.23.05.9

12.036.531.38.9

16.414.827.321.4

332.9502.8344.2282.4822.1121.3

1235.3315.5160.1100.4802.9390.7300.0761.0411.1115.9178.3499.9131.0593.2171.4134.2151.1126.2327.0165.2110.3536.9

5997.5210.5864.0110.1129.8133.4188.4235.1538.1540.8205.2201.7370.2789.3430.5

333.9502.3348.7285.7823.3115.9

1298.2327.6150.9100.1787.7391.9288.2742.4457.0121.3164.6487.9123.1596.2148.3114.9116.1124.2272.8113.6104.7541.7

5271.4210.1865.2110.1129.6133.6186.3238.6598.3560.9219.0199.4412.1799.3447.9

4.621.04.25.45.86.4

52.116.9

1.63.9

15.15.21.24.9

66.95.51.55.71.09.21.40.60.81.90.70.60.68.3

110.212.820.4

1.62.71.42.47.8

50.528.417.86.3

35.226.920.8

338.5523.3352.9291.1829.1122.3

1350.3344.5152.5104.0802.8397.1289.4747.3523.9126.8166.1493.6124.1605.4149.7115.5116.9126.1273.5114.2105.3550.0

5381.6222.9885.6111.7132.3135.0188.7246.4648.8589.3236.8205.7447.3826.2468.7

5.620.58.78.77.01.0

115.029.0-7.6

3.6-0.1

6.4-10.6-13.7112.8

10.9-12.2

-6.3-6.9

12.2-21.7-18.7-34.2

-0.1

-53.5-51.0-5.0

. 13.1

-615.912.421.6

1.62.51.60.3

11.3110.748.531.64.0

77.136.938.2

23T

able 2

Field

170 latan E.171 Jordan172 K

eystone173 M

cElroy

174 Means

175 Midland F

arms

176 Sa

nd

hills

177 Spraberry T

rend178 TX

L179 W

addell180 W

ard Este

sN.

181 Westbrook

182 Yates

183 Anton-lrish

184 Cogdell

185 Diam

ond M186 K

elly-Snyder

187 Levelland188 P

rentice189 S

alt Creek

190 Sem

inole191

Slaughter

192 Wasson

193 Welch

194 Panhandle

195 Altam

ont196 G

reater Aneth

197 Byron

198 Elk B

asin199 F

rannie200 G

arland201

Grass C

reek202 H

amilton D

ome

203 Hartzog D

raw204 Lance C

reek205 Little B

uffalo Basin

206 Lost Soldier

207 Oregon B

asin208 S

alt Creek

209 Wertz

Location D

iscovery C

um. P

roduction Rem

. Reserves E

st. Total R

ecovery Cum

. Production R

em. R

eserves Est. T

otal Recovery

Change in E

st. Y

ear as of 1/1/90

as of 1/1/90 as of 1/1/90

as of 1/1/98 as of 1/1/98

as of 1/1/98 Total R

ecovery

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8

Texas-D

ist. 8T

exas-Dist. 8A

Texas-D

ist. 8AT

exas-Dist. 8A

Texas-D

ist. 8AT

exas-Dist. 8A

Texas-D

ist. 8AT

exas-Dist. 8A

Texas-D

ist. 8AT

exas-Dist. 8A

Texas-D

ist. 8AT

exas-Dist. 8A

Texas-D

ist. 10U

tahU

tahW

yoming

Wyom

ingW

yoming

Wyom

ingW

yoming

Wyom

ingW

yoming

Wyom

ingW

yoming

Wyom

ingW

yoming

Wyom

ingW

yoming

1926193719301926193419441931195119441927192919201926

,19441949

:i1948

;194819381951195019361936193619421921195519561918191519281906191419181976191819141916191218891921

145.8129.9314.7472.2234.4245.6250.5672.1265.0101.3367.090.0

1199.3179.0293.5240.8

1253.5500.0166.3257.8541.1

1047.71738.1

147.21429.3

91.8359.6121.6434.8116.9165.4187.5232.8

72.3107.9121.2210.7396.4634.3103.8

9.21.67.8

50.214.215.019.339.0

5.03.2

73.614.0

755.221.139.914.796.534.415.025.025.032.060.011.014.0

228.825.0

6.722.8

4.16.46.66.0

277.90.39.05.8

25.020.211.0

155.0131.5322.5522.4248.6260.6269.8711.1270.0104.5440.6104.0

1954.5200.1333.4255.5

1350.0534.4181.3282.8566.1

1079.71798.1

158.21443.3320.6384.6128.3457.6121.0171.8194.1238.8350.2108.2130.2216.5421.4654.5114.8

165.3135.5325.7540.1275.6261.0268.0816.0276.9106.8391.1103.0

1356.1196.4299.7251.7

1295.5615.7198.6331.5656.3

1177.91964.1

167.71475.8

112.2405.0127.4452.1120.3182.9201.4249.5

96.5109.1131.3237.2441.8658.6113.4

12.73.05.5

36.425.3

7.613.095.911.23.6

23.56.6

598.410.13.76.0

54.548.624.546.457.577.9

122.520.131.115.925.02.4

12.01.37.75.65.8

12.10.93.0

19.119.617.58.7

178.0138.5331.2576.5300.9268.6281.0911.9288.1110.4414.6109.6

1954.5206.5303.4257.7

1350.0664.3223.1377.9713.8

1255.82086.6

187.81506.9

128.1430.0129.8464.1121.6190.6207.0255.3108.6110.0134.3256.3461.4676.1122.1

23.07.08.7

54.152.38.0

11.2200.8

18.15.9

-26.05.60.06.4

-30.02.20.0

129.941.895.1

147.7176.1288.529.663.6

-192.545.4

. 1.56.50.6

18.812.916.5

-241 .61.84.1

39.840.021.6

7.3

SU

MS

79284.514244.8

93529.389599.5

9825.899425.3

5896.0

24T

able 2

Table 3. Giant U.S. oil fields of Table 1 having significant remaining potential (those that account for 80% of annual production or 80% of remaining reserves). [Data are sorted by rank with respect to annual production. Rank with respect to remaining reserves is also shown. Production and reserves are in mmbo.]

ID No. Table 1

Field Rank- Rank- Production Rem. Reserves production rem. reserves in 1997 as of 1/1/98

10 Prudhoe Bay4 Kuparuk River

30 Midway-Sunset9 Point Mclntyre

27 Kern River 15 BelridgeS.

268 Wasson 246 Spraberry Trend

84 Garden Banks 4262 Endicott

23 Elk Hills 252 Yates

62 Wilmington 214 East Texas

8 Milne Point 191 Giddings 38 Hondo

267 Slaughter 40 Pescado21 Cymric

265 Seminole29 Lost Hills

261 Levelland 178 Sho-Vel-Tum

41 Point Arguello17 Coalinga

226 Cowden N. 264 Salt Creek

83 Eugene Island 330 161 Vacuum 103 South Pass 6163 Rangely

240 McElroy 106 South Pass 8988 Green Canyon 6593 Main Pass 299

231 Fullerton oon o-oater Aneth

78 Bay Marchand 246 Ventura

277 Panhandle 263 Robertson N. 227 Cowden S.-Foster-J.

6 McArthur River 101 South Pass 24 108 West Delta 3043 San Ardo

291 Oregon Basin 234 Howard-Glasscock 241 Means 232 Goldsmith 157 Grayburg-Jackson90 Main Pass 41

109 West Delta 7364 Jay96 Miss. Canyon 194

260 Kelly-Snyder47 Beta86 Grand Isle 43

SUMS

123456789

1011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545559616468

1249581417181173616102315203122263034291227323836485321454137394662422449545640575219747161597982336725281335

251.00096.00060.69259.00048.74642.84827.41023.41422.70621.00020.52920.31019.77919.21319.00016.59016.49115.50315.16113.84711.95011.52011.08010.80010.5639.7329.5959.1918.6558.0157.9147.5297.4557.2907.1336.9036.6555.8745.3115.1915.1255.1025.0155.0004.8504.7794.6294.4314.2154.2134.1984.0593.8413.8033.7773.2133.1453.0092.884

1076.883

3042.01111.0332.7241.0329.0272.3122.595.993.4

170.0288.6598.4290.9110.2223.066.9

121.477.951.768.657.551.948.652.1

160.757.150.546.447.531.229.270.436.441.646.545.135.225.040.966.831.128.928.444.027.929.682.819.620.825.326.918.317.749.623.159.054.5

140.548.1

9524.1

25 Table 3