1

Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

Chapter 10 Petroleum Systems of the San Joaquin Basin Province— Geochemical Characteristics of Gas Types

By Paul G. Lillis, Augusta Warden, George E. Claypool1, and Leslie B. Magoon

Contents Three general gas types are identified on the basis of bulk and stable carbon isotopic composition—ther­ Abstract------1 mogenic dry (TD), thermogenic wet (TW) and biogenic Introduction------2 (B). The thermogenic gas types are further subdivided Methods------3 13 Results------3 on the basis of the δ C values of methane and ethane Natural Gas Types------9 and nitrogen content into TD-1, TD-2, TD-Mixed, TW-1, Thermogenic Dry (TD)------9 TW-2, and TW-Mixed. Gas types TD-1 and TD-Mixed, a Thermogenic Wet (TW)------11 mixture of biogenic and TD-1 gases, are produced from Biogenic------11 Origin of Carbon Dioxide------11 gas fields in the northern San Joaquin Basin. Type TD-1 Petroleum Systems------11 gas most likely originated from the Late Cretaceous to Conclusions------11 Paleocene Moreno Formation, a gas-prone source rock. Acknowledgments------15 The biogenic component of the TD-Mixed gas existed in References Cited------15 the trap prior to the influx of thermogenic gas. For the Tables------19 Appendix (.xls file) assessment, these gas types were assigned to the Winters- Domengine Total Petroleum System, but subsequent to the assessment were reclassified as part of the Moreno- Abstract Nortonville gas system. Dry thermogenic gas produced from oil fields in the southern San Joaquin Basin (TD-2 The San Joaquin Basin Province is a petroliferous gas) most likely originated from the oil-prone source rock basin filled with predominantly Late Cretaceous to Plio­ of Miocene age. These samples have low wetness values cene-aged sediments, with organic-rich marine rocks of due to migration fractionation or biodegradation. Late Cretaceous, Eocene, and Miocene age providing the The thermogenic wet gas types (TW-1, TW-2, TW- source of most of the oil and gas. Previous geochemical Mixed) are predominantly associated gas produced from studies have focused on the origin of the oil in the prov­ oil fields in the southern and central San Joaquin Basin. ince, but the origin of the natural gas has received little Type TW-1 gas most likely originates from source rocks attention. To identify and characterize natural gas types in within the Eocene Kreyenhagen Formation or the Eocene the San Joaquin Basin, 66 gas samples were analyzed and Tumey formation of Atwill (1935). Type TW-2 gas most combined with analyses of 15 gas samples from previ­ likely originates from the Miocene Monterey Formation ous studies. For the purpose of this resource assessment, and equivalents. TW-Mixed gas is likely a mixture of bio­ each gas type was assigned to the most likely petroleum genic and wet thermogenic gas (TW-1 or TW-2) derived system. from source rocks mentioned above. The thermogenic wet gas types are included in the corresponding Eocene or Miocene total petroleum systems. Type B gas is a dry, nonassociated gas produced 1Research Geochemist, Lakewood, Colo. from the Pliocene San Joaquin Formation in the central 2 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California and southern San Joaquin Basin. This gas type most likely Introduction originated from Pliocene marine source rocks as a product of methanogenesis, and defines the Neogene Nonassoci- The Great Valley of California is a petroleum-productive ated Gas Total Petroleum System. Cretaceous-Paleogene forearc basin located between the Sierra

Index Stockton Map California

Modesto

San Jose San Joaquin Basin Province N

Fresno SIERRA

NEVADA DIABLO RANGE

San Joaquin SANTA Basin Province

SAN ANDREAS FAULT LUCIA

RANGE

TEMBLOR RANGE • Bakersfield N

SIERRA MADRE MTNS. S. TN I M AP CH EHA IO-T SAN EMIGD

Figure 10.1. Location map of San Joaquin Basin Province (red outline) showing topography and location of county lines and some cities. Inset shows location of San Joaquin Basin Province (red outline) within the State of California. 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 3

Nevada and Coast Ranges (primarily the Diablo and Temblor and characterize natural gas types, and to assign these types to Ranges; fig. 10.1). An east-west trending, subsurface struc­ the most likely petroleum system for the purpose of resource tural arch (Stockton Arch) separates the Great Valley into the assessment (Magoon and others, this volume, chapter 8). Sacramento Basin Province to the north and the San Joaquin Basin Province to the south. The Sacramento Basin is primar­ ily a gas province, whereas the San Joaquin Basin produces Methods mostly oil and some gas. The San Joaquin Basin is filled with Late Cretaceous to Pliocene-aged marine sediments (fig. 10.2), Sixty-six gas samples were analyzed for C1 to C7 and organic-rich marine rocks of Eocene and Miocene age hydrocarbons, CO2, CO, N2, O2, Ar, He, H2, and H2S using provide the source for most of its petroleum. a Wasson gas analyzer, a customized Hewlett-Packard gas Previous geochemical studies in the San Joaquin Basin chromatograph. Oxygen and argon cannot be differentiated have focused on the origin of the oil (see discussion in Lillis by this method, so the concentrations of these gases are and Magoon, this volume, chapter 9), but the origin of the reported together (O2+Ar). Because oxygen and argon con­ natural gas has received little attention. In the Sacramento centrations are generally very low in natural gas, the mea­

Basin Province, the natural gas geochemistry was studied by sured O2+Ar content in the gas samples is assumed to be air Jenden and Kaplan (1989b) and was reinterpreted in the con­ contaminant. Thus, the nitrogen content of the gas samples text of petroleum systems (Magoon and others, 1994; Magoon was corrected by reducing the measured nitrogen by the and others, 1996a; Magoon and others, 1996b; Claypool and amount of nitrogen from air contamination using the ratio others, 2000; Claypool and others, 2001; Hosford Scheirer and (O2+Ar)/N2=0.2802 (Mason and Moore, 1982, p. 211). This others, 2007a; Hosford Scheirer and others, 2007b). correction was not applied to the nitrogen data from Jenden Rudkin (1968) first addressed the gas chemistry in and Kaplan (1989a) because their analytical method differ­ the San Joaquin Basin with discussions of gas wetness, the entiates oxygen and argon. exceptionally high nitrogen content of gases in Chowchilla Stable carbon isotopes (δ13C) of methane, ethane, field, and the high hydrogen sulfide content of gases at East propane, butane and carbon dioxide were measured using Coalinga Extension field. Kaplan and others (1988) analyzed a Hewlett-Packard gas chromatograph interfaced with a 40 gas samples from the San Joaquin Basin and categorized Micromass Optima continuous-flow isotope ratio mass spec­ them into four genetic groups on the basis of carbon isotopic trometer (IRMS). The results are expressed in delta (δ) composition—two groups of associated thermogenic gases, notation, which represents the deviation of the 13C/12C ratio one group of nonassociated thermogenic gas, and one group of in parts per thousand (per mil or ‰) relative to the Peedee mixed microbial and thermogenic gas. Four gas samples from belemnite (PDB) standard. Gas wetness is reported as per­ the northern San Joaquin Basin were included in a study by cent C2+ hydrocarbon gases relative to total hydrocarbon

Jenden and others (1988) on the origin of nitrogen-rich natural gases using the expression [(ΣC2 to C5)/(ΣC1 to C5)] * 100. gas in the California Great Valley. Eleven gas analyses from the San Joaquin Basin were included in a broad study of more than 800 gas samples from around the United States (Jenden Results and Kaplan, 1989a). Kamerling and others (1989) recognized Pliocene biogenic gas in the southern San Joaquin Basin. In Gas sample information is listed in table 10.1 and more recent studies, Claypool and others (2000), Claypool and analytical results are listed in table 10.2. About 75 percent others (2001), and Lillis and others (2004) assigned the San of the gas samples in this study were taken from oil fields, Joaquin Basin gases to petroleum systems—a mixed biogenic- with the rest taken from gas fields (fig. 10.3), generally thermogenic gas attributed to the Winters-Domengine(?) gas reflecting the dominance of oil and associated gas produc­ system that extends southward from the Sacramento Basin, tion over nonassociated gas production in the San Joaquin a Pliocene to Pleistocene biogenic gas system, and two wet Basin Province. Natural gases from the San Joaquin Basin thermogenic gas types associated with oils from Eocene and Province exhibit a wide range of gas wetness values in

Miocene petroleum systems, respectively. [Note that the formal percent C2+ hydrocarbon gas (zero to 37 percent), and of names for petroleum systems consist of the source rock name, δ13C methane composition (–70.2 to –24.2‰; table 10.2, fig. followed by a hyphen, the principal reservoir name, and an 10.4). Nitrogen content is generally less than 2 percent (fig. indication of the certainty of the correlation (Magoon and Dow, 10.5), but many gas samples from the northern San Joaquin 1994). The symbols (?), (.), and (!) indicate speculative, hypo­ Basin (fig. 10.3) have high nitrogen (from 7 to 59 percent; thetical, and known genetic relationships, respectively.] samples 1, 14, 15, 32, 47, 48, 49, 52, 53, and 64; fig. 10.5). In this study, 66 gas samples were collected from the San The nitrogen correction is substantial in samples with sig­ Joaquin Basin Province and analyzed for bulk composition nificant air contamination (for example, samples 11, 20, 25, and stable carbon isotope ratios. These analytical results were 27, 28, 33, 36, 60, 63, and 75; table 10.2). Gas sample 16 combined with 15 gas samples from previous studies (Jenden is suspected to have high nitrogen because it came from a and Kaplan, 1989a; Claypool and others, 2000) to identify treatment vessel rather than from a well. 4 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

SAN JOAQUIN BASIN PROVINCE

SYSTEM Mega- NORTH CENTRAL SOUTH SERIES sequences West East West East West East Ma (2nd order) STAGE basin axis Alluvium basin axis Alluvium basin axis Alluvium 0 PLEIS. unnamed Tulare Fm San Joaquin Fm PLIO. San Joaquin Fm unnamed

5 unnamed Etchegoin Fm unnamed Etchegoin Fm Trans- Reef Ridge Sh Mbr Reef Ridge Sh Mbr pression Chanac Monterey Fm

DEL. Antelope sh KR Santa Margarita Santa Margarita Fm Ss McLure Shale Mbr Ss Stevens sd Santa Margarita 10 Monterey Fm Fruitvale shale Ss McDonald Sh Mbr MOHNIAN MOHNIAN unnamed

NEOGENE NEOGENE Devilwater Sh Round Mtn Silt LUI. unnamed migration Mbr/Gould Sh 15 Temblor Fm Mbr, undiff Nozu sd MIOCENE MIOCENE B REL. Triple junction Triple Media Sh Mbr Olcese Zilch fm Sand Zilch fm Carneros Ss Mbr 20 Temblor Fm Santos Santos Jewett

SAUCESIAN Freeman Sand Silt

Agua Ss Mbr Sh PH 25 magmatism . Bed

Rio Bravo sd

Vaqueros Fm 30 unnamed Walker Fm Subduction and Wygal Ss Mbr Vedder Sand ZEMORRIAN OLIGOCENE Cymric Shale Mbr REF. 35 Leda sd Tumey formation Tumey formation Oceanic sand

40 NARIZIAN Kreyenhagen Formation Kreyenhagen Formation Point of Rocks Ss

unnamed unnamed Mbr sand Famoso EOCENE EOCENE

Kreyenhagen Formation 45 Famoso sand Famoso subsidence subsidence

unnamed unnamed Canoas Slts Mbr Diablo Range Diablo unnamed uplift and basin and uplift Domengine Fm Domengine Fm Yokut B=Buttonbed Ss Mbr Ss PH=Pyramid Hill Sd Mbr KR=Kern River Fm 50 Arroyo Hondo Sh Mbr Gatchell sd PALEOGENE Cantua Ss Mbr Oil reservoir rock Gas reservoir rock unnamed

PENUTIAN ULATSIAN Potential marine Potential nonmarine reservoir rock reservoir rock 55 - Lodo Fm Nonmarine Marine coarse coarse grained TIAN BULI grained rock rock

orogeny San Carlos sd Clay/shale/ ~ ~ Coast Range mudstone/ ~ ~ ophiolite/ Granitic basement and Laramide biosiliceous ZIAN YNE- 60 Oil-prone source Hiatus or loss by rock/ erosion Gas-prone source rock Garzas Ss

Flat slab subduction Wheatville sd Moreno Fm PALEOCENE PALEOCENE undifferentiated

Moreno Fm Cretaceous 65 CHENEYIAN 121˚W 120˚W 119˚W 38˚N miles unnamed Stockton Arch basin axis San Joaquin0 Basin 25Province Blewett sds

70 MAASTRICH. Starkey sands COAST RANGES Tracy sds RVS Brown Mtn ss North Sawtooth shale Ragged Valley silt SIERRA NEVADA

75 Panoche Fm Joaquin Ridge Ss Mbr 37˚N Lathrop sd Sacramento shale Panoche Fm 80 LATE

CAMPANIAN CAMPANIAN Forbes fm SAN ANDREAS FAULT Central 85 SANT. ? ? DCN CON. RVS=Ragged Valley silt 36˚N DR DC T 90 PH South undifferentiated Cretaceous DD J

TUR. Bakersfield Arch marine and nonmarine strata

CRETACEOUS undifferentiated Cretaceous

95 marine and nonmarine strata Pacific Ocean WWF CENO. CENO. 35˚N 100 AINS SAN EMIGDIO,TECHAPI MOUNT Sierran magmatism magmatism Sierran 160 Ma 120 Ma 160 Ma 120 Ma 160 Ma 120 Ma

105 and margin Convergent EARLY EARLY

ALBIAN ALBIAN Basement rocks Basement rocks Basement rocks 110

Figure 10.2. San Joaquin Basin Province stratigraphy showing hydrocarbon reservoir rocks and potential hydrocarbon source rocks. See Hosford Scheirer and Magoon (this volume,Figure 10.2chapter 5) for complete explanation of the figure. Formation names in italics are informal and are defined as follows (in approximate age order): Forbes formation of Kirby (1943), Sacramento shale and Lathrop sand of Callaway (1964), Sawtooth shale and Tracy sands of Hoffman (1964), Brown Mountain sandstone of Bishop (1970), Ragged Valley silt, Starkey sands, and Blewett sands of Hoffman (1964), Wheatville sand of Callaway (1964), San Carlos sand of Wilkinson (1960), Gatchell sand of Goudkoff (1943), Oceanic sand of McMasters (1948), Leda sand of Sullivan (1963), Tumey formation of Atwill (1935), Famoso sand of Edwards (1943), Rio Bravo sand of Noble (1940), Nozu sand of Kasline (1942), Zilch formation of Loken (1959), Stevens sand of Eckis (1940), Fruitvale shale of Miller and Bloom (1939), and Antelope shale of Graham and Williams (1985). 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 5

121°30’ 121°00’ 120°30’ 120°00’ 119°30’ 119°00’ 118°30’ 38°00’

Gas sample 37°30’ 52 Sample Number Oil Field Gas Field

15 14 1 37°00’ 51 47 49 53 48 52

32 33

63 65 64 67 36°30’ 77

38

20 17 19 16 18

41 42 36°00’ 43

61 62 76

46

68 45 69 54 44 70 5 35°30’ 13 81 6 34 66 40 N 7 8 35 39 9 37 36 31 3 30 72 26 25 29 28 71 27 4 Pacific 2 21 73 24 22 23 11 55 Ocean 56 50 10 58 60 57 12 59

79 75 35°00’ 74 80 10 0 10 20 30 40 MILES 78

10 0 10 20 30 40 50 KILOMETERS

Figure 10.3. Locations of the gas samples in the San Joaquin Basin Province (gray shading) used in this study. Sample information is given in table 10.1. County boundaries are shown as thin brown lines. 6

-20 Petroleum SystemsandGeologicAssessmentofOilGasintheSanJoaquinBasinProvince,California

Thermogenic gas -30

20 66 -40

-50 Mixed gas C Methane (‰) 13 δδ δδ Gas Type -60 TD-1 TD-2 Biogenic gas TD-Mixed TW-1 -70 TW-2 TW-Mixed B Bo -80 0 5 10 15 20 25 30 35 40

Gas Wetness (percent C2+)

13 Figure 10.4. Plot of gas wetness (percent C 2+) versus δ C of methane for natural gas samples from the San Joaquin Basin Province. Wetness is defined as [(ΣC2 to C5)/(ΣC1 to C5)] * 100. Gas types are defined in the text and include thermogenic dry (subtypes TD-1, TD-2), thermogenic wet (subtypes TW-1, TW-2), mixed thermogenic-biogenic (subtypes TD-Mixed, TW-Mixed), biogenic (B), and biogenic outlier (Bo). -20

49 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES -30 Thermogenic gas 14

48 20 -40 66 64 31 32 47 1 -50 Mixed gas 53 52 15

C Methane (‰) 39

13 Gas Type δδ δδ -60 TD-1 Biogenic gas TD-2 TD-Mixed TW-1 -70 TW-2 TW-Mixed B Bo

-80 0 10 20 30 40 50 60 Corrected Nitrogen (mole percent)

13 Figure 10.5. Plot of percent nitrogen (corrected) versus δ C of methane for natural gas samples from the San Joaquin Basin Province. See text for explanation of nitrogen correction. 7 8

-20 66 Petroleum SystemsandGeologicAssessmentofOilGasintheSanJoaquinBasinProvince,California

-25

42 19 -30

increasing proportion of biogenic gas -35 increasing thermal maturity

-40 C Ethane (‰)

13 Mixed gas Thermogenic gas δδ δδ -45 Gas Type TD-1 TD-2 -50 TD-Mixed TW-1

-55 TW-2 TW-Mixed

-60 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15

δδ13C Methane (‰)

Figure 10.6. Plot of δ13C of methane versus δ13C of ethane for natural gas samples from the San Joaquin Basin Province. Trend arrows show increasing propor­ tion of biogenic methane mixed with thermogenic gas, as well as change in isotopic composition with increasing thermal maturity. 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 9

δ13C ethane values range from –38.4 to –21.5‰ (fig. higher nitrogen (greater than 8 percent, except for samples 10.6), and δ13C propane values range from –31.5 to –20.0‰ 20 and 31) than Type TD-2 gases. Thermogenic wet (TW) (table 10.2). The δ13C i-butane values range from –31.9 to gas is subdivided into two subtypes on the basis of δ13C –20.3‰, and the δ13C n-butane values range from –28.5 to methane and δ13C ethane values (fig. 10.6), with TW-1 gases –9.4‰ (table 10.2). Carbon dioxide content is generally less showing a distinct thermal maturity trend, and TW-2 gases than 1 percent, but ranges from 0 to 92 percent (table 10.2). showing a weak thermal maturity trend. Two biogenic gas

However, the sample with 92 percent CO2 (sample 40) may samples (Bo) are distinguished from the biogenic gas type be discounted, because the sample was taken from the surface (B) on the basis of nitrogen content (fig. 10.5). casing of a producing oil well. The δ13C carbon dioxide values of the gas samples range from –13.1 to +32.7‰ (table 10.2). Thermogenic Dry (TD)

Type TD-1 gas is produced from Cretaceous-aged res­ Natural Gas Types ervoir rocks in gas fields of the northern San Joaquin Basin Province (grey triangles, fig. 10.7), including Raisin City, Natural gas forms by either biogenic (B) or thermogenic Chowchilla, and Merrill Avenue Southeast fields. Clay- (T) processes (Bernard and others, 1977; Fuex, 1977; pool and others (2000) suggested that these gas accumula­ Schoell, 1980; Rice and Claypool, 1981). Biogenic gas (also tions may be an extension of the Winters-Domengine(?) called microbial gas) is generated in anaerobic, sulfate-free gas system of Magoon and others (1994) in the Sacramento sediments at temperatures less than 75°C by communities Basin on the basis of similar δ13C methane values and high of microbes that include fermentative bacteria, acetogenic nitrogen content. However, high nitrogen content is not bacteria, and a group of Archaea called methanogens. Ther­ a distinctive characteristic of the Winters-Domengine(?) mogenic gas, in contrast, is generated by the cracking of system; the nitrogen may be derived from metasedimentary kerogen or oil at higher temperatures with increasing burial. basement rocks (Jenden and others, 1988) rather than the The main stage of thermogenic gas generation from kerogen Cretaceous Winters formation of Edmondson (1962; hereaf­ occurs within the oil window, that is, at the same thermal ter referred to as Winters formation). Furthermore, a Winters maturity as oil generation. This is equivalent to a vitrinite formation source for TD-1 gas is problematic because the reflectance range of 0.6 to 1.2 percent. Stockton Arch separates thermally mature Winters forma­ Biogenic gas is composed of isotopically light methane tion in the Sacramento Basin Province from the northern San (δ13C generally less than –55‰; Rice and Claypool, 1981), Joaquin Basin Province (see Hosford Scheirer and Magoon, whereas thermogenic gas is composed of isotopically heavier this volume, chapter 21, for a detailed discussion). methane and varying amounts of higher hydrocarbon gases A more likely source for the TD-1 gas is the Creta­ (measured as gas wetness). On the basis of stable carbon ceous to Paleocene Moreno Formation in the San Joaquin isotopic composition and gas wetness, the gas samples ana­ Basin Province, which has good source rock characteristics lyzed can be grouped into three gas types—thermogenic (McGuire, 1988; Peters, Magoon, Valin, and others, this dry (TD), thermogenic wet (TW), and biogenic (B). The volume, chapter 11), and is thermally mature down-dip from boundary between TD and TW gas is empirically placed these gas fields that contain TD-1 gas. Unfortunately, we at a wetness value of 2.5 percent C2+. This wetness bound­ lack a gas sample to analyze from the Moreno Formation ary is consistent with the definition of Tissot and Welte reservoir rock, such as Cheney Ranch field, that may derive (1984)—dry gas has a methane to total hydrocarbon gas from the Moreno Formation source rock. A gas seep from ratio greater than 0.97 (wetness less than 3 percent C2+). On the Oil City pool at Coalinga field (sample 20), which may the basis of a natural break in the data (figs. 10.4 and 10.6) derive from the Moreno Formation, matches TD-1 gas on thermogenic gas samples with δ13C methane values less the basis of δ13C methane and wetness values (fig. 10.4). than –45‰ are interpreted to be a mixture of biogenic and However, on the basis of evidence of air contamination (high thermogenic gas (TD-Mixed and TW-Mixed). The boundary O2+Ar), the quality of the sample is in question. between TD-Mixed and biogenic (B) gas is placed at a δ13C The TD-Mixed gas is a mixture of thermogenic dry and methane value of -55‰ on the basis of Rice and Claypool biogenic gases found in Cretaceous, Eocene, and Miocene (1981), although there is a natural break in the data at -60‰. reservoir rocks in gas fields of the northern San Joaquin 13 All wet gases (greater than 2.5 percent C2+) with δ C meth­ Basin (open triangles, fig. 10.7). The geographic distribu­ ane values less than -45‰ are classified as TW-Mixed (table tion, reservoir rock age, and elevated nitrogen content (as 10.3). much as 11 percent) of this gas type is similar to TD-1 gas The thermogenic dry and wet gas types are further sub­ and is considered genetically related. The biogenic gas divided. Thermogenic dry (TD) gas is subdivided into two component of TD-Mixed gas most likely originated from the subtypes on the basis of δ13C methane values (fig. 10.4) and microbial decomposition of organic matter in the Cretaceous nitrogen content (fig. 10.5). Type TD-1 gas has higher δ13C (and possibly Eocene) aged sediments. Two gases assigned methane (greater than –41‰, except for sample 66) and to the TD-Mixed gas (samples 15 and 52) are interpreted 10 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

121°30’ 121°00’ 120°30’ 120°00’ 119°30’ 119°00’ 118°30’ 38°00’

Gas Types TD-1 TD-2 TD-Mixed 37°30’ 52 Sample Number Oil Field Gas Field

15 14 37°00’ 51 1 47 53 49 52 48 32 33

64 65

36°30’

20

36°00’

54 35°30’ 8 66 N 31 28 Pacific 24 Ocean

35°00’ 10 0 10 20 30 40 MILES

10 0 10 20 30 40 50 KILOMETERS

Figure 10.7. Sample locations for thermogenic dry gas in the San Joaquin Basin Province (gray shading). Figure 10.7 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 11 to be predominantly biogenic on the basis of light (low) Biogenic δ13C methane values (–53.8 to –54.75‰) but have elevated nitrogen similar to other TD-Mixed gas. Although typed as The biogenic (B) gas is a dry, nonassociated gas produced TD-Mixed, the gas sample from Mount Poso field (sample in the central and southern San Joaquin Basin (fig. 10.9) from 54) is probably unrelated to other TD-Mixed or TD-1 gases, shallow (less than 5,000 feet) reservoir rocks within the Plio­ cene San Joaquin Formation. The gas is characterized by low because it is produced from an oil field in the southern San 13 Joaquin Basin (fig. 10.7). Slightly elevated propane and (light) δ C methane values (–56 to –70‰), low carbon dioxide butane (table 10.2) in the sample suggests a small component (less than 0.5 percent), and low nitrogen (less than 0.3 percent). of wet thermogenic gas mixed with a biogenic gas. Type The B gas most likely originated from the microbial decomposi­ TD-2 gas is discussed below with thermogenic wet gases. tion (methanogenesis) of marine organic matter in the Pliocene San Joaquin Formation during and soon after deposition. This gas type defines the Neogene Nonassociated Gas Total Petro­ Thermogenic Wet (TW) leum System (Magoon and others, this volume, chapter 8). Two outlier gas samples (Bo) have isotopically light δ13C The thermogenic wet (TW) gas of the San Joaquin methane values, typically characteristic of biogenic gas, but Basin Province is generally produced from oil fields (fig. appear to be unrelated to the B gas type (fig. 10.5). Gas sample 10.8), and most likely originates from the same source rocks 39 from Kern Bluff field is distinct because it is an associ­ as the coproduced oil. The TW-1 gas is produced from ated gas with high nitrogen produced from the Miocene Santa Eocene and Oligocene-aged reservoir rocks, and most likely Margarita Sandstone. Gas sample 50 from Midway-Sunset field originated from source rocks within the Eocene Kreyenha­ is distinct because it contains elevated nitrogen and carbon diox­ gen Formation or Tumey formation of Atwill (1935; hereaf­ ide and is associated with oil produced from the Miocene Reef ter referred to as Tumey formation). Ridge Shale Member of the Monterey Formation. The origin Most TW-2 gas is produced from Miocene reservoir of these two gases is unknown but the anomalous composi­ rocks, but it also occurs in Jurassic, Eocene, Oligocene tion may be an artifact of sampling or field production practice and Pliocene-aged reservoir rocks. The most likely source (table 10.1). rock for TW-2 gas is the Miocene Monterey Formation and equivalents. Two exceptions in the samples classified as TW-2 gas are samples 19 and 42, which come from fields Origin of Carbon Dioxide producing TW-1 gas (fig. 10.8) and oil sourced from the Eocene Kreyenhagen Formation (Lillis and Magoon, this Carbon dioxide in the San Joaquin Basin Province has at volume, chapter 9, their samples 26 and 179). Further, these least two possible origins. For gas samples that have less than 2 two samples are located more than 30 miles north of other percent carbon dioxide and negative δ13C carbon dioxide values, TW-2 gas. On figure 10.6 they plot close to the TW-1 gas the carbon dioxide is likely a minor byproduct of the thermal samples suggesting that they may be genetically related to degradation of organic matter (Hunt, 1996). For gas samples the latter. with a carbon dioxide content greater than 2 percent and iso­ TW-Mixed gas is a mixture of biogenetic gas and wet topic δ13C values between +2 and +24‰, the carbon dioxide thermogenic gas (TW-1 or TW-2) most likely derived from may be the residual gas from methanogenesis produced during Eocene or Miocene source rocks. The biogenic gas com­ petroleum biodegradation. Most of these gas samples (samples ponent of TW-Mixed gas most likely originated from the 6, 7, 8, 9, 10, 17, 23, 24, 25, 26, 50, 62, and 66) are produced microbial decomposition of organic matter in Eocene or from shallow reservoir rocks (less than 5,000 feet depth) that Miocene aged sediments. contain biodegraded oil. A similar process has been suggested The TD-2 gas is produced with oils from Miocene to for the origin of isotopically heavy carbon dioxide in some Los Pliocene (Fruitvale, Elk Hills, Edison, Rosedale Ranch, and Angeles Basin oil fields (Jeffrey and others, 1991). South Belridge fields) and Jurassic-aged (Edison field) reser­ voir rocks in the southern San Joaquin Basin (fig. 10.7). The TD-2 gas appears to be genetically related to the thermogenic Petroleum Systems wet gas (TW-2) and oils produced from the same fields, but is drier due to migration fractionation or biodegradation of For the purpose of resource assessment, the gas types ethane and higher hydrocarbons (James and Burns, 1984). characterized above were assigned to petroleum systems. The For example, the gas sample produced from Rosedale Ranch TD-1 and TD-Mixed gas types were assigned to the Winters- field (sample 66) has a distinctly high (heavy) δ13C ethane Domengine Total Petroleum System. Subsequent to the assess­ value (fig. 10.6) due to bacterial consumption of ethane and ment, these gas types were reclassified to form the basis of higher hydrocarbons. Two TW-2 gas samples from Edison the Moreno-Nortonville(.) gas system (fig. 10.10). The TW-1, field (samples 25 and 26) appear to have biodegraded TW-2, TW-Mixed and TD-2 gas types are considered to be propane on the basis of higher (heavier) δ13C values than associated gases that are included in the corresponding Eocene normally expected (James, 1983; James and Burns, 1984). or Miocene total petroleum systems (Magoon and others, this 12 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

121°30’ 121°00’ 120°30’ 120°00’ 119°30’ 119°00’ 118°30’ 38°00’

Gas Types TW-1 TW-2 TW-Mixed 37°30’ 55 Sample Number Oil Field Gas Field

37°00’

63 67

36°30’ 77

38

17 19 16 18 41 43 36°00’ 42

62 61

46

68 69 44 5 45 35°30’ 6 81 7 40 9 35 34 N 37 3 26 30 36 73 72 2 29 27 21 4 25 Pacific 71 22 55 Ocean 10 60 56 11 57 12

79 75 74 35°00’ 80 10 0 10 20 30 40 MILES 78

10 0 10 20 30 40 50 KILOMETERS

Figure 10.8. Sample locations for thermogenic wet gas in the San Joaquin Basin Province (gray shading). Figure 10.8 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 13

121°30’ 121°00’ 120°30’ 120°00’ 119°30’ 119°00’ 118°30’ 38°00’

Gas Types B 37°30’ Bo 50 Sample Number Oil Field Gas Field

37°00’

36°30’

36°00’

76

70

35°30’ 13 N 39

Pacific Ocean 50 58 59

35°00’ 10 0 10 20 30 40 MILES

10 0 10 20 30 40 50 KILOMETERS

Figure 10.9. Sample locations for biogenic gas in the San Joaquin Basin Province (gray shading). Figure 10.9 14 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California 40 1 2 B TD-2 TD-1 TD-Mixed TW- TW- TW-Mixed 35 Gas Type Gas Type < < 30 Gas TPS Gas Moreno- Neogene assigned to Nonassociated associated gas Nortonville (.) PS petroleum systems ) Eocene and Miocene 2+ 25 20 15 Gas Wetness (percent C Gas Wetness 10 C of methane for natural gas samples from San Joaquin Basin Province with symbol color representing petroleum sys­ 13 δ

5 66 20 Plot of gas wetness versus

0

-20 -30 -40 -50 -60 -70 -80

δδ δδ C Methane (‰) (‰) Methane C 13 13 tem assignment. Type TD-1 and Type TD-Mixed gases are assigned to the Moreno-Nortonville(.) gas system (black triangles). Type TW-1, TW-2, TW-Mixed, and TW-Mixed, TW-2, tem assignment. TW-1, TD-Mixed gases are assigned to the Moreno-Nortonville(.) gas system (black triangles). Type TD-1 and Type Type TD-2 gases are assigned to Eocene and Miocene petroleum systems (blue circles triangless). B gas defines the Neogene Nonassociated system Type (yellow squares). PS, petroleum system; TPS, total system. Figure 10.10. 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 15 volume, chapter 8). The B gas defines the Neogene Nonas­ Elizabeth Rowan, Keith Kvenvolden and Zenon Valin). The sociated Gas Total Petroleum System (Magoon and others, this manuscript was greatly improved by the comments and sug­ volume, chapter 8). gestions from Ken Peters, Joseph Hatch, and Allegra Hosford Scheirer (USGS). Conclusions References Cited Natural gases in the San Joaquin Basin Province can be grouped into three general types on the basis of bulk and Atwill, E.R., 1935, Oligocene Tumey Formation of California: Bulletin of the American Association of Petroleum stable carbon isotopic composition—thermogenic dry, ther­ Geologists, v. 19, no. 8, p. 1192-1204. mogenic wet, and biogenic. The thermogenic gas types can be 13 Bernard, B., Brooks, J.M., and Sackett, W.M., 1977, A further subdivided on the basis of δ C values of methane and ethane and nitrogen content into TD-1, TD-2, TD-Mixed, TW-1, geochemical model for characterization of hydrocarbon gas TW-2, and TW-Mixed. sources, in Offshore Technology Conference, 9th, Houston, The dry thermogenic gas TD-1 is produced from gas fields Tex., 1977, Proceedings: p. 435-438. in the northern San Joaquin Basin Province, and most likely Berryman, W.M., 1973, Lithologic characteristics of Pliocene originated from gas-prone source rocks of Cretaceous age. The rocks cored at Elk Hills, Kern County, California: U.S. TD-Mixed gas is a mixture of dry thermogenic and biogenic Geological Survey Bulletin 1332-D, 56 p. pper Cretaceous stratigraphy on the gases produced from Cretaceous, Eocene, and Miocene reservoir Bishop, C.C., 1970, U west side of the Northern San Joaquin Valley, Stanislaus rocks in the northern San Joaquin Basin Province. These two gas and San Joaquin counties, California: Sacramento, Calif., types are assigned to the Moreno-Nortonville(.) gas system, but, California Division of Mines and Geology Special Report alternatively, may be part of the Winters-Domengine Total Petro­ 104, 29 p. leum System of the Sacramento Basin. The dry thermogenic Callaway, D.C., 1964, Distribution of uppermost Cretaceous gas TD-2 is produced from oil fields in the southern San Joaquin sands in the Sacramento-Northern San Joaquin Basin Basin, and most likely originated from an oil-prone source rock of California: Selected Papers Presented to San Joaquin of Miocene age. Low wetness values in this gas type likely results Geological Society, v. 2, p. 5-18. from migration fractionation or biodegradation. CDOGGR, 1998, California oil and gas fields: Sacramento, The three wet thermogenic gases, or TW-1, TW-2, and Calif., California Department of Conservation, Division of TW-Mixed, are predominantly gases associated with produced Oil, Gas, and Geothermal Resources, Publication No. CD-1, oil from fields in the southern and central San Joaquin Basin. The TW-1 gas is produced from Eocene and Oligocene-aged 1472 p. reservoir rocks, and most likely originates from source rocks Claypool, G.E., Magoon, L.B., Lorenson, T.D., Lillis, P.G., within the Eocene Kreyenhagen Formation or Tumey formation. and Kaplan, I.R., 2001, Natural gas in the Great Valley of The TW-2 gas is produced from Jurassic, Eocene, Miocene, and California—Geochemical characterization and petroleum

Pliocene reservoir rocks, and most likely originates from a source systems [abs.], in Annual Meeting, Denver, Colo., 2001, rock in the Miocene Monterey Formation and equivalents. The Expanded Abstracts: American Association of Petroleum TW-Mixed gas is likely a mixture of wet thermogenic (TW-1 or Geologists, p. 37. TW-2) gases derived from Eocene or Miocene source rocks and Claypool, G.E., Magoon, L.B., Lorenson, T.D., Valin, Z.C., biogenic gas. These three gas types are included in the resource Warden, A., Lillis, P.G., and Kaplan, I.R., 2000, Natural assessments of the corresponding oil systems (Magoon and gas in the Great Valley of California—Characterization, others, this volume, chapter 8). origin and petroleum systems [abs.], in AAPG Pacific The biogenic gas (type B) is a dry, nonassociated gas pro­ Section/SPE Western Region Conference Joint Conference duced from the Pliocene San Joaquin Formation in the central and of Geoscientists and Petroleum Engineers, Long Beach, Association of Petroleum Geologists southern San Joaquin Basin. The B gas most likely originated Calif., 2000: American Bulletin, v. 84, no. 6, p. 863. from Pliocene marine source rocks as a product of methanogen­ Eckis, R., 1940, The Stevens sand, southern San Joaquin esis and defines the Neogene Nonassociated Total Petroleum Valley, California [abs.]: Bulletin of the American System. Association of Petroleum Geologists, v. 24, no. 12, p. 2195-2196. Acknowledgments Edmondson, W.F., 1962, Stratigraphy of the late Upper Cretaceous in the Sacramento Valley: Selected Papers Analytical work was performed by Augusta Warden at Presented to San Joaquin Geological Society, v. 1, p. 17-26. the USGS Organic Geochemistry Lab, Denver, Colo. Zenon Edwards, E.C., 1943, Kern Front area of the Kern River Valin made the final figures. Numerous operators, too many oil field, in Jenkins, O.P., ed., Geologic formations to list here, kindly allowed access for sampling by the USGS and economic development of the oil and gas fields of (Les Magoon, George Claypool, Paul Lillis, Tom Lorenson, California: San Francisco, Calif., State of California, 16 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

Department of Natural Resources, Division of Mines Jeffrey, A.W., Alimi, H.M., and Jenden, P.D., 1991, Bulletin No. 118, p. 571-574. Geochemistry of Los Angeles Basin oil and gas systems, Foss, C.D., and Blaisdell, R., 1968, Stratigraphy of the in Biddle, K.T., ed., Active margin basins: Tulsa, Okla., west side southern San Joaquin Valley, in Karp, S.E., ed., American Association of Petroleum Geologists Memoir 52, Guidebook, Geology and oil fields, West side southern San p. 197-219. Joaquin Valley: Pacific Sections, American Association Jenden, P.D., and Kaplan, I.R., 1989a, Analysis of gases in the of Petroleum Geologists, Society of Exploration Earth’s crust—Final report to the Gas Research Institute, Geophysicists, Society of Economic Paleontologists and Chicago, GRI Report Number 88/0262, Contract Number Mineralogists, 43rd Annual Meeting, p. 33-43. 5081-360-0533, in Kaplan, I.R., ed., 2000, Collection of Frame, R.G., 1950, Helm oil field,in Summary of operations, papers about the oil, gas, and source rock investigations California oil fields: San Francisco, Calif., Annual Report carried out in the San Joaquin, Santa Maria, Santa Barbara, of the State Oil and Gas Supervisor, v. 36, no. 1, p. 5-14 Ventura, and Los Angeles basins, California: Bakersfield, [also available in California Division of Oil and Gas, Calif., Pacific Section, American Association of Petroleum Summary of Operations, 1915-1999: California Division Geologists CD-ROM Series 1, 300 p. of Conservation, Division of Oil, Gas, and Geothermal Jenden, P.D., and Kaplan, I.R., 1989b, Origin of natural gas Resources, Publication No. CD-3, and at ftp://ftp.consrv. in Sacramento Basin, California: American Association of ca.gov/pub/oil/Summary_of_Operations/1950/]. Petroleum Geologists Bulletin, v. 73, no. 4, p. 431-453. Fuex, A.N., 1977, The use of stable carbon isotopes in Jenden, P.D., Kaplan, I.R., Poreda, R.J., and Craig, H., 1988, hydrocarbon exploration: Journal of Geochemical Origin of nitrogen-rich natural gases in the California Great Exploration, v. 7, no. 2, p. 155-188. Valley—Evidence from helium, carbon and nitrogen isotope Goudkoff, P.P., 1943, Correlation of oil field formations ratios: Geochimica et Cosmochimica Acta, v. 52, no. 4, p. on west side of San Joaquin Valley, in Jenkins, O.P., ed., 851-861. Geologic formations and economic development of the oil Kamerling, M., Lewy, R.M., and Lundell, L.L., 1989, and gas fields of California: San Francisco, Calif., State of Biogenic origin of Pliocene dry gas, southern San Joaquin California, Department of Natural Resources, Division of Basin, California [abs.], in AAPG-SEPM-SEG-SPWLA Mines Bulletin No. 118, p. 247-252. Pacific Section Annual Meeting, Palm Springs, Calif., 1989: Graham, S.A., and Williams, L.A., 1985, Tectonic, American Association of Petroleum Geologists Bulletin, v. depositional, and diagenetic history of Monterey Formation 73, no. 4, p. 542-543. (Miocene), central San Joaquin Basin, California: American Kaplan, I.R., Alimi, M.H., Lu, S.T., Jeffrey, A., Shepard, L.S., Association of Petroleum Geologists Bulletin, v. 69, no. 3, Meredith, D.E., and Polovini, J.S., 1988, The petroleum p. 385-411. geochemistry of crude oils and potential source rocks from Hoffman, R.D., 1964, Geology of the northern San Joaquin the Paleogene of the San Joaquin and Ventura/Santa Barbara Valley: Selected Papers Presented to San Joaquin basins, data synthesis and text, v. 1, in Kaplan, I.R., ed., Geological Society, v. 2, p. 30-45. 2000, Collection of papers about the oil, gas, and source Hosford Scheirer, A., Magoon, L.B., Tennyson, M.E., and rock investigations carried out in the San Joaquin, Santa Peters, K.E., 2007a, Uplift and erosion, distribution of Maria, Santa Barbara, Ventura, and Los Angeles basins, mature source rock, and burial histories for two gas systems California: Bakersfield, Calif., Pacific Section, American in the Sacramento Basin, California [abs.], in Annual Association of Petroleum Geologists CD-ROM Series 1, Convention and Exhibition, Long Beach, Calif., 2007: 283 p. American Association of Petroleum Geologists Bulletin, v. Kasline, F.E., 1942, Edison oil field,in Summary of 91 (digital). operations, California oil fields: San Francisco, Calif., Hosford Scheirer, A., Tennyson, M.E., Magoon, L.B., Annual Report of the State Oil and Gas Supervisor, v. 26, p. Charpentier, R.R., Cook, T.A., Klett, T.R., Pollastro, R.M., 12-18 [also available in California Division of Oil and Gas, and Schenk, C.J., 2007b, Assessment of undiscovered Summary of Operations, 1915-1999: California Division natural gas resources of the Sacramento Basin Province of Conservation, Division of Oil, Gas, and Geothermal of California, 2006, U.S. Geological Survey Fact Sheet Resources, Publication No. CD-3, and at ftp://ftp.consrv. 2007-3014, 2 p. [http://pubs.usgs.gov/fs/2007/3014/]. ca.gov/pub/oil/Summary_of_Operations/1940/]. Hunt, J.M., 1996, Petroleum geochemistry and geology (2nd Kirby, J.M., 1943, Upper Cretaceous stratigraphy of the ed.): New York, Freeman and Company, 743 p. west side of Sacramento Valley south of Willows, Glenn James, A.T., 1983, Correlation of natural gas by use of carbon County, California: Bulletin of the American Association of isotopic distribution between hydrocarbon components: Petroleum Geologists, v. 27, no. 3, p. 279-305. American Association of Petroleum Geologists Bulletin, v. Lillis, P.G., Warden, A., Claypool, G.E., and Magoon, L.B., 67, no. 7, p. 1176-1191. 2004, Natural gas in the San Joaquin Basin—Geochemical James, A.T., and Burns, B.J., 1984, Microbial alteration of characterization of the petroleum systems [abs.], in Pacific subsurface natural gas accumulations: American Association Section Convention, Pacific Sections AAPG, SEPM, & SEG, of Petroleum Geologists Bulletin, v. 68, no. 8, p. 957-960. Bakersfield, Calif., 2004, Abstracts: American Association of 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 17

Petroleum Geologists Bulletin, v. 88, no. 13 (Supplement). Mitchell, M.D., and Chamberlain, C.R., 1983, An analysis Loken, K.P., 1959, Gill Ranch gas field, in Summary of of stimulation treatments of the Randolph sand in the operations, California oil fields: San Francisco, Calif., Semitropic field, Kern County, California,in California Annual Report of the State Oil and Gas Supervisor, v. 45, Regional Meeting, Ventura, Calif., 1983: Society of no. 1, p. 27-32 [also available in California Division of Oil Petroleum Engineers Paper Number 11709, p. 413-418. and Gas, Summary of Operations, 1915-1999: California Noble, E.B., 1940, Rio Bravo oil field, Kern County, Division of Conservation, Division of Oil, Gas, and California: Bulletin of the American Association of Geothermal Resources, Publication No. CD-3, and at ftp:// Petroleum Geologists, v. 24, no. 7, p. 1330-1333. ftp.consrv.ca.gov/pub/oil/Summary_of_Operations/1959/]. Rice, D.D., and Claypool, G.E., 1981, Generation, Magoon, L.B., Castaño, J.R., Lillis, P., MacKevett, N.H., and accumulation, and resource potential of biogenic gas: Naeser, N., 1994, Two petroleum systems in the Sacramento American Association of Petroleum Geologists Bulletin, v. Basin, California—A basis for new discoveries [abs.], in 65, no. 1, p. 5-25. Pacific Section Meeting, Ventura, Calif., 1994: American Rudkin, G.H., 1968, Natural gas in San Joaquin Valley, Association of Petroleum Geologists Bulletin, v. 78, no. 4, California, in Beebe, B.W., and Curtis, B.F., eds., Natural p. 669. gases of North America: Tulsa, Okla., American Association Magoon, L.B., and Dow, W.G., 1994, The petroleum system, of Petroleum Geologists Memoir 9, p. 113-134. in Magoon, L.B., and Dow, W.G., eds., The petroleum Schoell, M., 1980, The hydrogen and carbon isotopic system—From source to trap: Tulsa, Okla., American composition of methane from natural gases of various Association of Petroleum Geologists Memoir 60, p. 3-24. origins: Geochimica et Cosmochimica Acta, v. 44, no. 5, p. Magoon, L.B., Valin, Z.C., and Lillis, P.G., 1996a, Petroleum 649-662. systems in the Sacramento Basin, California, USA [abs.], Sullivan, J.C., 1963, Guijarral Hills oil field,in Summary in International Conference and Exhibition, Caracas, of operations, California oil fields: San Francisco, Calif., Venezuela, 1996, Abstracts: American Association of Annual Report of the State Oil and Gas Supervisor, v. 48, Petroleum Geologists Bulletin, v. 80, no. 8, p. 1310. no. 2, p. 37-51 [also available in California Division of Oil Magoon, L.B., Valin, Z.C., and Reid, R.A., 1996b, and Gas, Summary of Operations, 1915-1999: California Characterization of gas fields by petroleum system, Division of Conservation, Division of Oil, Gas, and Sacramento Basin, California [abs.], in Annual Meeting, Geothermal Resources, Publication No. CD-3, and at ftp:// San Diego, Calif., 1996, Abstracts: American Association of ftp.consrv.ca.gov/pub/oil/Summary_of_Operations/1962/]. Petroleum Geologists, v. 5, p. A88. Tissot, B.P., and Welte, D.H., 1984, Petroleum formation and Mason, B., and Moore, C.B., 1982, Principles of geochemistry occurrence: Berlin, Springer-Verlag, 699 p. (4th ed.): New York, Wiley, 344 p. Wilkinson, E.R., 1960, Vallecitos field,in Summary of McGuire, D.J., 1988, Stratigraphy, depositional history, and operations, California oil fields: San Francisco, Calif., hydrocarbon source-rock potential of the Upper Cretaceous- Annual Report of the State Oil and Gas Supervisor, v. Lower Tertiary Moreno Formation, central San Joaquin 45, no. 2, p. 17-33 [also available in California Division Basin, California: Stanford, Calif., Stanford University, of Oil and Gas, Summary of Operations, 1915-1999: Ph.D. dissertation, 309 p. California Division of Conservation, Division of Oil, McMasters, J.H., 1948, Oceanic sand [abs.]: Bulletin of the Gas, and Geothermal Resources, Publication No. CD-3, American Association of Petroleum Geologists, v. 32, no. and at ftp://ftp.consrv.ca.gov/pub/oil/Summary_of_ 12, p. 2320. Operations/1959/]. Miller, R.H., and Bloom, C.V., 1939, Mountain View oil Williams, R.N., Jr., 1938, Recent developments in the field, in Summary of operations, California oil fields: North Belridge oil field, in Summary of operations, San Francisco, Calif., Annual Report of the State Oil and California oil fields: San Francisco, Calif., Annual Report Gas Supervisor, v. 22, no. 4, p. 5-36 [also available in of the State Oil and Gas Supervisor, v. 21, no. 4, p. 5-16 California Division of Oil and Gas, Summary of Operations, [also available in California Division of Oil and Gas, 1915-1999: California Division of Conservation, Division Summary of Operations, 1915-1999: California Division of Oil, Gas, and Geothermal Resources, Publication No. of Conservation, Division of Oil, Gas, and Geothermal CD-3, and at ftp://ftp.consrv.ca.gov/pub/oil/Summary_of_ Resources, Publication No. CD-3, and at ftp://ftp.consrv. Operations/1937/]. ca.gov/pub/oil/Summary_of_Operations/1936/]. 18 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

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Tables 20 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California 2-29S-21E 7-20S-16E 1-29S-21E 8-10S-14E 8-10S-14E 26 31S-23E 32-10S-14E 30-30S-22E 25-31S-23E 31-19S-16E 34-29S-26E 10-30S-26E 35-27S-20E 29-28S-21E 36-31S-23E 33-28S-21E 25-27S-22E 27-19S-15E 32-19S-15E Sec-Twn-Rng --­ (feet) 775 - 2,615 5,441 - 5,594 6,550 - 1,420 - 2,700 2,900 - 3,390 6,666 - 6,973 7,695 - 8,040 8,200 - 8,500 7,530 - 7,572 7,820 - 7,867 1,490 - 2,390 1,195 - 3,020 2,070 - 2,300 7,924 - 2,605 - 4,000 - 5,000 4,000 - 1,122 - 1,724 Depth Interval Well Name Redman-Roduner 1-32 Midway-McKittrick 21A Belridge V 7384B­ 2 Crimson Sec 25B 1-7A plant treater Coalinga Nose Unit 3-7F Coalinga Nose Unit 26-31B Argonaut 1 KCL 61 52X-10 63-35 29 573-29 33 577CR-33 Sebu T 7624-1 36 B McNee 5-8 Chowchilla 3 Chowchilla 5 Crimson 523 Buttonwillow 1 Coalinga 45-27 Comments gas well just south of Ash Slough gas field oil well oil well oil well oil well oil well oil well oil well shallow gas well gas well gas well from oil treater (no. 3) for many wells, suspect sample well produces only gas but was oil producer from oil and gas separator oil well gas well oil well oil well oil well a b B TD-2 TD-1 TW-1 TW-2 TW-2 TW-2 TW-2 TW-1 TW-1 TW-2 TW-2 TW-1 TW-2 TD-Mixed TD-Mixed Gas Type TW-Mixed TW-Mixed TW-Mixed Reservoir Rock Blewett sands of Hoffman (1964) Stevens sand of Eckis (1940) Stevens sand of Eckis (1940) Belridge 64 sand of Foss and Blaisdell (1968) Etchegoin Fm/Reef Ridge Sh Mbr of Monterey Fm Etchegoin Fm/Reef Ridge Sh Mbr of Monterey Fm Monterey Fm/Reef Ridge Sh Mbr of Monterey Fm/Etchegoin Fm Reef Ridge Sh Mbr of Monterey Fm Mya sand zone of Berryman (1973) Starkey sands of Hoffman (1964) (third) Zilch formation of Loken (1959) Gatchell sand of Goudkoff (1943) Gatchell sand of Goudkoff (1943) Kreyenhagen Shale Etchegoin Formation Monterey Formation San Joaquin Formation --­ Temblor Formation Formation Name Temblor Formation Etchegoin Formation Monterey Formation San Joaquin Formation San Joaquin Formation Panoche Formation --­ Temblor Formation Blewett sands of Hoffman (1964) Fruitvale shale of Miller and Bloom (1939) Fruitvale shale of Miller and Bloom (1939) Etchegoin Fm/Reef Ridge Sh Mbr of Monterey Fm Etchegoin Fm/Reef Ridge Sh Mbr of Monterey Fm Monterey Fm/Reef Ridge Sh Mbr of Monterey Fm/Etchegoin Fm Reef Ridge Sh Mbr of Monterey Fm Zilch formation of Loken (1959) Lodo Formation Lodo Formation Field Name Ash Slough Belgian Anticline Kreyenhagen Shale Bellevue Bellevue Belridge North Belridge South Belridge South Belridge South Belridge South Buena Vista Buena Vista Buena Vista Buttonwillow Chowchilla Chowchilla Coalinga Coalinga Coalinga East Extension Coalinga East Extension Sample information for natural gas samples from the San Joaquin Basin Province, California. 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 10 19 Gas Sample Number Table 10.1. Table TD- biogenic (B), thermogenic mixed with (TW-Mixed, TW-2), [Gas types are based on gas composition (table 10.2) and designated as thermogenic dry (TD-1, TD-2), wet (TW-1, Mixed), and biogenic outlier (Bo). Field names are designated by the State of California, Division Oil, Gas, Geothermal Resources (CDOGGR, 1998). Formation name reservoir rock modified to Member; Sh, Shale. See appendix for more information on each location of sample in notation public land survey system. Fm, Formation; Mbr, comply with USGS geologic name standards. Sec-Twn-Rng, sample] Table 10.1. Sample information for natural gas samples from the San Joaquin Basin Province, California—Continued.

Gas Depth Interval Sample Field Name Formation Name Reservoir Rock Gas Type Comments Well Name Sec-Twn-Rng (feet) Number 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES Coalinga, Oil from seep in water tank near gas seep in water 20 Moreno (?) Formation Moreno (?) Formation c --­ 17-19S-15E City area TD-1 abandoned well tank Coles Levee, Antelope shale of Graham North Coles Levee 21 Monterey Formation TW-2 oil well 8,814 - 9,187 32-30S-25E North and Williams (1985) Unit 76-32 Coles Levee, Antelope shale of Graham South Coles Levee 22 Monterey Formation TW-2 oil well 8,245 - 8,584 9-31S-25E South and Williams (1985) Unit 72-9 Young Fee Dos 23 Edison Kern River Formation Kern River Formation TD-2 from tank battery of oil well 1,961 - 2,192 23-30S-29E Tres 72 24 Edison schist schist TD-2 oil well Young Fee 13 2,050 - 2,200 23-30S-29E 25 Edison schist schist TW-2 oil well Corp Fee 35 1,336 - 1,833 13-30S-29E 26 Edison schist schist TW-2 oil well Corp. Fee S 2 1,740 - 1,740 13-30S-29E Antelope shale of Graham 27 Elk Hills Monterey Formation TW-2 from tank for several oil wells 358-31S 6,036 - 7,008 31-30S 24E and Williams (1985) 28 Elk Hills San Joaquin Formation San Joaquin Formation TD-2 gas well DZG 405X-36R 1,781 - 1,896 36-30S-23E well produces only gas but 29 Elk Hills San Joaquin Formation San Joaquin Formation TW-Mixed 4-242-33R 2,110 - 2,205 33-30S-23E was oil producer Carneros Ss Mbr of 30 Elk Hills Temblor Formation TW-2 oil well 542-30R 9,485 - 9,850 30-30S-23E Temblor Fm from separator for several oil 31 Fruitvale Chanac Formation Chanac Formation TD-2 separator 3F approx. 4,300 22-29S-27E wells 32 Gill Ranch Panoche Formation Panoche Formation TD-Mixed gas well Gill 38-16 5,750 - 5,750 16-13S-16E 33 Gill Ranch Panoche Formation Panoche Formation TD-Mixed gas well Gill 38X-17 5,000 - 7,000 20-13S-16E 34 Greeley Freeman Silt-Jewett Sand Freeman Silt-Jewett Sand TW-2 oil well KCL 12-8 11,234 - 11,327 7-29S-26E 35 Greeley Freeman Silt-Jewett Sand Freeman Silt-Jewett Sand TW-Mixed oil well KCL 51 114-7 10,260 - 10,652 7-29S-26E Fruitvale shale of Miller and Fruitvale shale of Miller and 36 Greeley TW-Mixed oil well KCL 63 43-20 8,677 - 9,143 20-29S-26E Bloom (1939) Bloom (1939) 37 Greeley Vedder Sand Vedder Sand TW-2 from well casing of oil well KCL 12-9 11,292 - 11,332 7-29S-26E Zilch formation of Loken Zilch formation of Loken oil well, southeast area of 38 Helm TW-Mixed Covey 3X 7,057 - 7,061 33-17S-19E (1959) (1959) field from separator for several oil 39 Kern Bluff Santa Margarita Sandstone Santa Margarita Sandstone d separator 1,066 - 1,109 12-29S-28E Bo wells San Joaquin Fee 40 Kern River Kern River Formation Kern River Formation TW-Mixed from shut-in oil well casing 380 - 750 5-29S-28E 769 Kettleman North lower McAdams sandstone oil well, total depth = 10,060 41 Lodo Formation TW-1 E 72-33 approx. 10,000 33-21S-17E Dome of Sullivan (1963) ft

Kettleman North upper McAdams sandstone 42 Lodo Formation e oil well E 423-34 J 9,680 - 9,910 34-21S-17E Dome of Sullivan (1963) TW-2

Total depth = 6326 ft, Kettleman North 43 Temblor Formation Temblor Formation TW-Mixed originally a gas well (now oil 31-18 Q approx. 6,000 18-22S-18E 21 Dome and gas) 22 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California 6-26S-21E 1-29S-26E 2-32S-26E 4-32S-26E 4-32S-26E 3-27S-22E 15 27S-28E 12 12S-14E 16-27S-21E 20-12S-15E 28-24S-18E 14-31S-22E 10-11S-13E 33-11S-14E 29-11S-14E 31-10S-13E 19-15S-18E 23-31S-29E 26-31S-29E 25-31S-29E 29-24S-18E 13-15S-17E 13-15S-17E 31-15S-17E Sec-Twn-Rng (feet) 737 - 857 gt 17,000 4,546 - 4,782 16-27S-21E 2,300 - 2,700 3,974 - 3,985 3,542 - 3,600 1,516 - 1,690 4,190 - 4,328 6,102 - 6,286 6,220 - 6,243 6,377 - 6,756 6,344 - 6,371 4,087 - 4,500 - 5,000 5,696 - 6,418 6,930 - 7,013 5,605 - 6,140 5,672 - 5,676 4,385 - 5,465 6,174 - 6,300 7,574 - 7,584 approx. 1,600 approx. 7,800 approx. 18,300 Depth Interval 19,370 - 19,698 Well Name Monte Cristo 16 1741 Monte Cristo Fee 41 Shale 284-D Columbia Ranch 2­ 2 Norris-Drilexico- Hand 15 KCL 31 16-1 Berkeley 1 Wolfson 1-10 Triangle-T 1-33 Triangle-T 1-29 Bertao 1-31 N.M.R. 8-12 Paloma 28X-2 B 22X-19 Jewett 1-23 Simpson 1 Stockton 3 Paloma 43X-4 Paloma 44-4 Norris/Baylis 2-9 Ripperdan 56-13 Ripperdan 501-13 Schramm 71 EKHO 1 Comments gas well from separator of oil well gas well with condensate gas well gas well gas well oil well, steam (from field injection) mixed with gas sample gas well gas well from tank for several oil wells Glide 15-5 oil/condensate well oil well oil well with high water production gas well gas well from oil and gas separator oil well oil well oil well oil well oil well gas well oil well gas and condensate well oil well g f B B Bo TD-1 TD-1 TD-1 TD-2 TW-2 TW-2 TW-2 TW-2 TW-2 TW-1 TW-2 TD-Mixed TD-Mixed TD-Mixed TD-Mixed TD-Mixed Gas Type TW-Mixed TW-Mixed TW-Mixed TW-Mixed TW-Mixed TD-Mixed Reef Ridge Sh Mbr of Monterey Fm Gibson sand of Williams (1938) Blewett sands of Hoffman (1964) Blewett sands of Hoffman (1964) Ragged Valley silt of Hoffman (1964) Reef Ridge Sh Mbr of Monterey Fm Blewett sands of Hoffman (1964) Nortonville sand of Frame (1950) Carneros Ss Mbr of Temblor Fm Zilch formation of Loken (1959) Kreyenhagen Shale Vedder Sand Chanac Formation Chanac Formation schist San Joaquin Formation San Joaquin Formation Kreyenhagen Shale Kreyenhagen Shale Kreyenhagen Shale Panoche Formation Etchegoin Formation Domengine Formation --­ Temblor Formation Kreyenhagen Shale Kreyenhagen Shale Vedder Sand Chanac Formation Chanac Formation schist San Joaquin Formation San Joaquin Formation Temblor Formation Kreyenhagen Shale Kreyenhagen Shale Kreyenhagen Shale Panoche Formation Etchegoin Formation Domengine Formation --­ Reef Ridge Sh Mbr of Monterey Fm Blewett sands of Hoffman (1964) Blewett sands of Hoffman (1964) Panoche Formation Reef Ridge Sh Mbr of Monterey Fm Blewett sands of Hoffman (1964) Zilch formation of Loken (1959) Field Name Formation Name Reservoir Rock Lost Hills Lost Hills Monterey Formation Lost Hills, East Monterey Formation Merrill Avenue Merrill Avenue, SE Merrill Avenue, SE Midway-Sunset Mint Road Moffat Ranch Moffat Ranch Mount Poso Mountain View Mountain View Mountain View Paloma Paloma Paloma Pyramid Hills Pyramid Hills Raisin City Raisin City Raisin City Rosedale Ranch San Joaquin Semitropic Sample information for natural gas samples from the San Joaquin Basin Province, California—Continued. 46 53 62 45 44 48 49 50 51 52 54 55 56 57 58 59 60 61 63 64 65 66 67 68 47 Gas Sample Number Table 10.1. Table Table 10.1. Sample information for natural gas samples from the San Joaquin Basin Province, California—Continued.

Gas Depth Interval Sample Field Name Formation Name Reservoir Rock Gas Type Comments Well Name Sec-Twn-Rng (feet) Number 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES Randolph sand of Mitchell dual completion - oil zone, 69 Semitropic Etchegoin Formation TW-Mixed Community 1 7,500 - 8,000 14-27S-23E and Chamberlain (1983) from separator dual completion - gas zone, 70 Semitropic San Joaquin Formation San Joaquin Formation B Community 1 3,000 - 4,000 14-27S-23E from separator 71 Stockdale Round Mountain Silt Round Mountain Silt TW-Mixed oil well Panama 2-14 11,073 - 11,140 14-30S-27E 72 Stockdale Round Mountain Silt Round Mountain Silt TW-Mixed oil well Panama 2-15 11,150 - 11,250 15-30S-27E 73 Stockdale Round Mountain Silt Round Mountain Silt TW-Mixed oil well Panama 3-15 11,035 - 11,170 15-30S-27E 74 Tejon, North Vedder Sand Vedder Sand TW-2 oil well KCL "L" 67-25 8,710 - 8,710 25-11N-20W Vedder Sand-Tejon Vedder Sand-Tejon KCL-G North 65­ 75 Tejon, North TW-2 from separator of oil well 8,475 - 10,695 24-11N-20W Formation Formation 24 Mya sand zone of 76 Trico San Joaquin Formation B gas well Trico-Newland 12 2,427 - 2,427 21-24S-23E Berryman (1973) Zilch formation of Loken Zilch formation of Loken 77 Van Ness Slough TW-Mixed oil well Kleinhammer 1 approx. 6,900 11-17S-19E (1959) (1959) 78 Wheeler Ridge Olcese Sand (lower) Olcese Sand (lower) TW-Mixed oil well KCL "L" So. 56-36 7,460 - 7,460 36-11N-20W 79 Wheeler Ridge Tejon Formation Tejon Formation TW-1 oil well WRU 312-28 10,140 - 10,552 28-11N-20W 80 Wheeler Ridge Vedder Sand Vedder Sand TW-2 oil well KCL G 34-27 8,880 - 8,880 27-11N-20W from oil and gas drill stem 81 wildcat well --­ --­ TW-2 Bravo 1 approx. 14,300 17-28S-23E test

a Probably Type TW-1 gas but has high nitrogen and lacks 13C ethane data to confirm. b Possibly Type TW-1 gas on the basis of location, association with Eocene oil and TW-1 gas, and location as shown on figure 10.6. c Has low, corrected nitrogen compared with other TD-1 gases, and sample quality is in question due to air contamination. d Different origin from Type B gas because it has high nitrogen and is associated gas. e Possibly Type TW-1 gas on the basis of location, association with Eocene oil and TW-1 gas, and location as shown on figure 10.6. f Different origin from Type B gas because it has high nitrogen and carbon dioxide and is associated gas. g Different origin than other TD-Mixed or TD-1 gases because it is produced in southern San Joaquin Basin from an oil field (see text). 23 24 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California , 4 2 --­ --­ 0.5 -C % 0.02 0.55 0.41 0.84 1.58 1.31 0.44 1.56 0.15 0.03 0.85 0.52 0.46 0.04 0.01 0.02 0.19 1.23 0.49 1.38 1.14 1.49 i 0.937 3 --­ --­ 3 3.5 % C 0.04 5.07 4.74 4.07 2.48 0.62 7.99 2.53 2.97 1.76 0.06 0.06 0.07 7.06 1.72 5.36 4.74 7.66 2.13 0.078 0.001 12.39 2 0.2 6.6 % C +Ar, oxygen plus argon; O +Ar, 6.21 6.75 2.51 1.64 1.18 6.76 0.45 3.52 3.46 0.06 0.33 0.63 0.25 9.61 4.94 1.05 2.73 6.61 6.88 4.98 2 11.17 0.374 0.027 10.33 1 % C 82.51 82.31 55.96 59.74 81.00 60.90 83.38 80.25 48.91 92.51 73.67 84.56 97.53 40.70 88.20 86.62 94.51 81.55 60.09 75.73 74.16 57.46 79.50 75.96 67.67 87.65 , nitrogen; O 2 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ % He 0.01 0.013 0.001 2 +Ar)/0.2802. N 2 % --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ H --­ --­ --­ --­ --­ --­ --­ --­ --­ -(O 2 S --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 2 % H 0.02 0.03 , isobutane] 4 2 % 1.01 1.53 4.22 5.12 4.92 1.09 2.49 0.01 0.19 3.31 3.85 6.45 0.00 0.13 0.90 2.69 0.95 0.53 1.26 CO 13.60 11.63 15.58 15.35 10.10 17.51 23.98 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ , propane; i -C 3 % Ar 0.069 0.016 0.015 0.027 2 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ % O , ethane; C 0.04 0.13 2 0.418 0.013 --­ --­ --­ --­ +Ar % 2 0.77 1.32 8.13 4.75 0.76 0.28 0.43 0.46 0.90 3.27 0.61 0.64 0.57 0.53 0.52 0.72 0.95 0.69 0.72 1.11 0.51 0.59 O , methane; C 1 corr, corrected nitrogen content, using the expression N corr, 2 2 % N 2.25 3.80 6.37 2.90 1.12 1.11 1.38 2.77 1.51 1.67 1.65 1.32 1.49 2.28 1.72 1.64 3.42 1.28 1.76 31.41 20.95 59.10 10.80 35.98 10.67 12.28 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 --­ --­ --­ --­ corr % 2.39 0.19 0.12 2 34.34 10.25 N , hydrogen; He, helium; C 2 Lab No. 99003004 99003003 02025001 02025002 02025004 02025005 02025018 02025003 02025019 02025034 02025033 99003006 99003023 02025020 02025037 02025035 02025039 02025038 02025036 99003005 02025012 02025040 GGC-1181 GGC-1146 GGC-1148 GGC-1180 S, hydrogen sulfide; H 2 , carbon dioxide; H 2 Field Name Geochemical data of natural gas samples from the San Joaquin Basin Province, California. Coles Levee, North Coles Levee, South Edison Coalinga, Oil City area Edison Coalinga Coalinga East Extension Coalinga East Extension Edison Coalinga Edison Buena Vista Buena Vista Buttonwillow Chowchilla Chowchilla Ash Slough Belgian Anticline Belridge South Buena Vista Belridge South Belridge South Belridge South Bellevue Bellevue Belridge North 1 2 9 6 7 8 3 4 5 21 22 23 20 26 17 18 19 25 16 24 11 12 13 14 15 10 Gas Sample Number Table 10.2 A . Table Colo., except numbers starting with GGC- (Jenden and Kaplan, Denver, [Sample information is given in table 10.1. Lab No., analysis number for U.S. Geological Survey Organic Geochemistry Laboratory, 1989a) and M- (Claypool others, 2000). Gas compositions are in mole percent. N oxygen; Ar, argon; CO oxygen; Ar, Table 10.2 A. Geochemical data of natural gas samples from the San Joaquin Basin Province, California—Continued.

Gas N2corr N2 O2+Ar O2 CO2 H2S H2 C1 C2 C3 i -C4 Sample Field Name Lab No. Ar He Number % % % % % % % % % % % % % 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 27 Elk Hills 99003002 0 7.89 3.47 --­ --­ 0.64 --­ --­ --­ 80.73 5.52 1.49 0.17 28 Elk Hills 99003001 0 8.76 2.54 --­ --­ 2.90 --­ --­ --­ 84.89 0.68 0.17 0.02 29 Elk Hills 02025032 0 2.27 0.95 --­ --­ 0.47 --­ --­ --­ 92.97 1.82 1 0.2 30 Elk Hills 02025031 0.04 0.93 0.25 --­ --­ 4.25 --­ --­ --­ 79.52 8.03 3.56 0.8 31 Fruitvale 99003011 11.94 14.76 0.79 --­ --­ 0.51 --­ --­ --­ 83.59 0.33 0.03 --­ 32 Gill Ranch GGC-1151 --­ 8.35 --­ 0.014 0.012 0.01 --­ --­ 0.01 90.30 0.796 0.115 0.007 33 Gill Ranch 99003019 3.4 12.79 2.63 --­ --­ 0.10 --­ --­ --­ 83.78 0.62 0.08 --­ 34 Greeley 02025016 0.29 1.79 0.42 --­ --­ 1.06 --­ --­ --­ 75.74 10.37 6.51 0.71 35 Greeley 02025015 0.13 2.45 0.65 --­ --­ 1.05 --­ --­ --­ 66.48 4.69 11.09 3.74 36 Greeley 02025013 0 6.84 2.05 --­ --­ 2.36 --­ --­ --­ 74.14 2.23 4.79 2.05 37 Greeley 02025014 0.15 1.97 0.51 --­ --­ 3.41 --­ --­ --­ 82.75 7.28 3.81 --­ 38 Helm 99003015 0.82 1.07 0.07 --­ --­ 0.80 --­ --­ --­ 84.70 7.48 3.96 0.54 39 Kern Bluff 02025021 11.45 14.73 0.92 --­ --­ 0.42 --­ --­ --­ 83.93 --­ --­ --­ 40 Kern River 02025026 0 3.52 1.60 --­ --­ 92.24 --­ --­ --­ 1.72 --­ 0.39 0.17 41 Kettleman North Dome M-1 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 42 Kettleman North Dome M-2 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 43 Kettleman North Dome M-3 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 44 Lost Hills 02025042 0 2.88 1.02 --­ --­ 0.70 --­ --­ --­ 80.28 8.27 4.39 0.72 45 Lost Hills 99003012 0.19 2.01 0.51 --­ --­ 0.68 --­ --­ --­ 82.58 7.28 4.22 0.59 46 Lost Hills, East 02025041 0 0.46 0.13 --­ --­ 5.65 --­ --­ --­ 83.84 6.55 1.74 0.54 47 Merrill Avenue 99003025 9.4 12.36 0.83 --­ --­ 0.16 --­ --­ --­ 86.20 0.36 0.07 0.03 48 Merrill Avenue, SE 99003022 23.96 27.99 1.13 --­ --­ 0.00 --­ --­ 0.11 70.39 0.31 0.05 0.02 49 Merrill Avenue, SE 99003021 32.29 39.21 1.94 --­ --­ 0.13 --­ --­ --­ 58.55 0.15 0.03 --­ 50 Midway-Sunset 02025030 5.94 7.23 0.36 --­ --­ 43.24 0.04 4.1 --­ 44.08 0.24 0.15 0.2 51 Mint Road 99003024 4.54 4.79 0.07 --­ --­ 0.18 --­ --­ --­ 94.55 0.33 0.06 0.03 52 Moffat Ranch 99003020 10.03 13.10 0.86 --­ --­ 0.37 --­ --­ --­ 85.41 0.21 --­ --­ 53 Moffat Ranch GGC-1150 --­ 7.61 --­ 0.021 0.012 0.06 --­ --­ 0.01 91.40 0.289 0.049 0.005 54 Mount Poso 02025025 6.36 9.43 0.86 --­ --­ 0.32 --­ --­ --­ 88.48 0.17 0.36 0.18 55 Mountain View 02025023 1.24 4.17 0.82 --­ --­ 0.00 --­ --­ --­ 73.68 8.69 7.91 1.4 56 Mountain View 02025024 1.41 4.09 0.75 --­ --­ 0.00 --­ --­ --­ 71.03 9.43 8.29 1.78 57 Mountain View 02025022 5.39 7.28 0.53 --­ --­ 0.00 --­ --­ --­ 67.55 10.05 9.13 1.54 58 Paloma 99003008 0 1.58 0.54 --­ --­ 0.49 --­ --­ --­ 97.27 0.05 0.04 0.02 25 26 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California --­ --­ --­ --­ 4 2.5 1.81 2.69 0.16 1.21 0.51 2.33 0.17 0.81 0.19 0.12 0.02 1.62 1.84 0.34 1.12 1.21 -C % 0.986 0.863 i --­ 8.6 3 4.77 1.15 7.76 0.03 3.27 13.1 0.85 1.14 0.44 0.13 0.02 4.72 3.05 0.02 4.18 5.15 6.58 % C 11.11 12.33 12.14 0.002 --­ 2 3.97 3.79 7.57 4.01 0.05 7.42 2.04 1.21 1.03 0.79 0.93 4.13 1.92 0.04 7.05 5.01 8.76 7.93 % C 10.11 14.17 16.03 0.033 --­ 1 % C 64.71 75.90 76.20 81.99 73.01 97.33 79.64 61.85 88.99 85.06 85.35 88.65 80.86 83.95 62.57 87.97 95.73 67.23 99.00 77.50 79.20 75.50 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ % He 0.001 0.001 0.003 0.001 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 2 % H 0.005 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ S 2 % H --­ 2 1.50 0.08 1.32 0.03 0.50 0.85 0.11 0.35 0.16 0.12 7.39 0.56 0.07 2.85 0.68 0.98 0.30 0.14 0.91 0.04 0.02 % 15.92 CO --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ % Ar 0.012 0.003 0.025 0.013 0.022 --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ --­ 2 0.02 % O 0.129 0.346 0.274 0.291 --­ --­ --­ --­ --­ --­ 0.99 0.70 3.94 0.94 0.53 2.69 0.37 0.26 2.14 0.86 1.32 0.74 0.08 0.27 1.98 0.84 0.88 +Ar % 2 O --­ 2 1.65 3.29 0.22 5.43 1.94 8.68 2.93 0.93 2.54 1.71 5.93 0.67 0.23 7.93 6.14 1.51 1.25 0.48 4.07 3.23 2.00 % N 11.84 0 0 0 0 0 0 0 0 0 0 0 0 --­ --­ --­ --­ --­ --­ 0.29 8.77 1.43 0.96 0.23 corr % 2 N M-4 Lab No. 02025009 02025010 99003007 99003016 99003009 99003010 02025006 02025007 02025029 02025028 99003017 02025017 99003018 02025008 99003014 99003013 02025011 GGC-1176 GGC-1153 GGC-1177 GGC-1178 GGC-1179 Field Name Stockdale Tejon, North Stockdale Tejon, North Trico Van Ness Slough Wheeler Ridge Paloma Paloma Pyramid Hills Pyramid Hills Raisin City Raisin City Raisin City Rosedale Ranch San Joaquin Semitropic Semitropic Semitropic Stockdale Wheeler Ridge Wheeler Ridge wildcat well Geochemical data of natural gas samples from the San Joaquin Basin Province, California—Continued. 73 74 72 75 76 77 78 60 61 62 63 64 65 66 67 68 69 70 71 79 80 59 81 Gas Sample Number Table 10.2 A . Table Table 10.2 B. Additional geochemical data of natural gas samples from the San Joaquin Basin Province, California.

[Sample information is given in table 10.1. Lab No., analysis number for U.S. Geological Survey Organic Geochemistry Laboratory, Denver, Colo., except numbers starting with GGC- (Jenden and Kaplan, 1989a) and M- (Claypool and others, 2000). Gas compositions are in mole percent. n-C4, normal butane; i-C5, isopentane (2-methyl butane); n-C5, normal pentane; neo-C5, neopentane (2,2-dimethyl propane); 13 n-C6, normal hexane; n-C7, normal heptane; Wetness, percent C2+, using the expression [(ΣC2 to C5)/(ΣC1 to C5)]*100. δ C in per mil relative to Peedee belemnite standard; δD in per mil relative to Standard Mean Ocean Water standard] 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES

Gas neo- 13 13 13 13 13 13 13

Sample Field Name n -C4 i -C5 n -C5 C5 n -C6 n -C7 benzene wetness C1 D C1 C2 D C2 C3 i -C4 n -C4 CO2 C5 Number % % % % % % % % ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ 1 Ash Slough ------0.47 -47.78 ------­ 2 Belgian Anticline 1.92 0.685 0.39 ------16.12 -36.30 -156 -29.50 -132 -28.90 ------­ 3 Bellevue 2.57 0.2 0.11 ------19.64 -46.91 --- -29.78 --- -27.14 ------­ 4 Bellevue 4.56 0.08 0.78 --- 0.3 0.1 --- 30.46 -46.05 --- -30.45 --- -27.96 -26.87 -24.39 --- --­ 5 Belridge North 0.8 0.18 0.12 --- 0.03 ------9.04 -37.46 --- -29.03 --- -27.38 -25.15 -24.42 -0.03 --­ 6 Belridge South 1.24 0.31 0.23 --- 0.07 ------6.36 -41.30 --- -30.86 --- -29.56 -28.24 -25.14 9.29 --­ 7 Belridge South 4.25 1.18 0.95 --- 0.29 0.02 --- 21.62 -41.65 --- -28.63 --- -26.91 -26.76 -23.56 19.16 --­ 8 Belridge South 0.21 0.02 0.02 ------0.92 -44.96 ------20.65 --­ 9 Belridge South 2.95 0.78 0.64 --- 0.23 ------27.04 -42.13 --- -27.54 --- -27.78 -28.33 -25.15 8.12 --­ 10 Buena Vista 1.68 0.49 0.36 --- 0.14 ------13.50 -41.07 --- -27.12 --- -27.16 -28.40 -24.85 16.13 --­ 11 Buena Vista 1.15 0.23 0.14 --- 0.02 ------10.38 -42.91 --- -28.95 --- -26.66 -22.12 -21.73 -0.76 --­ 12 Buena Vista 0.79 0.18 0.15 --- 0.07 ------7.44 -39.84 --- -24.12 --- -23.00 -22.25 -18.64 18.91 --­ 13 Buttonwillow ------0.16 -57.79 ------­ 14 Chowchilla 0.009 0.006 0.004 ------1.17 -34.00 -143 -36.80 ------­ 15 Chowchilla --- 0.001 0.001 ------0.03 -53.80 -199 ------­ 16 Coalinga 0.43 0.15 0.08 0.02 0.03 ------5.76 -43.28 ------11.48 --­ 17 Coalinga 3.85 0.89 0.56 0.02 0.19 ------26.21 -48.46 --- -32.38 --- -31.09 -31.89 -28.47 13.71 --­ 18 Coalinga East Extension 0.11 0.02 0.08 --- 0.04 0.02 --- 14.43 -39.47 --- -31.06 --- -28.93 ------2.72 --­ 19 Coalinga East Extension 2.17 0.52 0.48 --- 0.26 0.09 0.02 16.06 -40.82 --- -29.44 --- -28.66 -29.09 -26.77 -4.01 --­ 20 Coalinga, Oil City area --- 0.02 ------0.50 -38.65 ------21.40 --­ 21 Coles Levee, North 1.35 0.16 0.12 ------14.03 -42.73 --- -28.10 --- -27.60 ------­ 22 Coles Levee, South 0.68 0.12 0.07 ------11.82 -40.06 --- -26.17 --- -25.43 ------­ 23 Edison ------0.66 -42.73 ------16.65 --­ 24 Edison ------0.02 ------0.54 -42.18 ------15.52 --­ 25 Edison 0.49 0.72 0.02 0.03 ------13.62 -41.52 --- -28.83 --- -20.76 -25.42 -9.41 14.17 --­ 26 Edison 0.37 1.1 0.005 ------7.86 -39.10 -255 -27.40 --- -20.00 ------24.00 --­ 27 28 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California 5 C 13 2 CO 13 4

-C n 13 4

-C i 13 3 C 13 2 D C 2 C 13 1 D C 1 C

13

wetness benzene 7

-C n 6

-C n - 5 C neo 5

-C n 5

-C i 4 ------0.00 -56.28 ------­ ------0.43 -43.23 --- 0.83 --- -45.83 ------18.23 --- --­ --- --­ ------0.53 -47.78 ------­ ------0.11 -58.53 ------­ --- 0.03 0.17 --- 0.07 ------12.01 -42.78 --- -30.13 --- -26.81 -28.84 -25.22 -5.92 --­ ------0.04 0.44 0.25 -51.66 -54.75 ------­ --­ 0.2 ------1.02 -48.62 ------­ -C % % % % % % % % ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ 0.21 0.04 0.02 0.09 ------34.85 -48.71 ------32.70 --­ 0.09 0.04 ---0.28 --- 0.02 ---1.45 0.02 0.43 ------0.37 ------0.27 ---2.15 --- 0.1 --- 0.06 0.09 --- 15.55 0.55 ------39.79 ------8.26 3.47 -39.87 0.42 --- -51.10 1.06 0.18 -25.34 -42.12 ------25.75 -27.82 -23.61 21.20 --- -20.34 -43.09 -19.93 ------25.96 -1.07 -24.11 ------30.06 --­ ------28.55 -25.69 --- -24.92 ------4.34 ------­ --­ --­ --- 16.24 --­ 1.16 0.18 ------0.02 1.48 0.02 13.59 0.02 1.53 -47.31 0.2 0.27 0.63 0.31 --- 0.21 --- -30.92 0.12 --- 0.04 0.03 ------30.54 0.08 --- 0.02 0.25 --- 0.03 ------10.46 0.04 15.81 0.03 -42.12 14.67 -41.49 -41.64 ------0.03 -25.51 -29.08 --- 0.02 -30.19 ------21.91 -27.52 --- -24.64 -25.14 -19.19 -27.98 2.02 -21.17 --­ -57.56 -1.20 ------­ --­ ------­ ------2.11 --­ 2.91 0.03 3.18 0.35 0.89 3.37 0.48 --- 0.04 0.04 0.45 --- 0.09 ------0.06 ------22.42 --- -43.55 25.29 --- -45.48 26.68 --- -40.64 -29.03 --- -28.93 ------28.13 -28.30 -28.95 --- -24.22 -27.67 -27.47 --- -22.75 -26.40 -26.11 --- -22.20 --- --­ --- --­ --­ 8.14 0.15 4.34 1.33 0.07 0.87 --- 0.22 --- 0.26 ------30.47 --- -49.05 16.22 -50.58 --- -27.60 --- -25.46 --- -30.11 -29.30 --- -25.13 -31.50 -29.04 -25.60 --- 0.37 --­ --­ n 0.006 0.003 0.001 ------1.02 -47.90 -193 -38.40 ------­ 0.012 0.006 0.009 ------0.40 -51.70 -200 -31.40 ------­ Field Name Additional geochemical data of natural gas samples from the San Joaquin Basin Province, California—Continued. Merrill Avenue, SE ------0.54 -37.82 ------­ 39 40 Kern Bluff Kern River 27 Elk Hills 28 29 Elk Hills 30 Elk Hills 31 Elk Hills 32 Fruitvale 33 Gill Ranch 34 Gill Ranch Greeley 38 Helm 41 42 Kettleman North Dome 43 Kettleman North Dome 44 --- Kettleman North Dome 45 --- Lost Hills ---46 --- Lost Hills ---47 Lost Hills, East ------48 Merrill Avenue ------49 ------50 --- Merrill Avenue, SE ------Midway-Sunset ------33.85 --- -38.52 ------46.06 -28.37 ------28.22 ------27.55 --- -29.18 --- -27.62 ------27.23 -27.42 ------27.46 ------0.31 -26.82 -28.44 -24.19 --- -27.85 ------26.99 ------­ 53 54 Moffat Ranch 55 Mount Poso 56 Mountain View 57 Mountain View 58 Mountain View Paloma 35 36 Greeley 37 Greeley Greeley 51 52 Mint Road Moffat Ranch Gas Sample Number Table 10.2 B . Table 0ETROLEUM3YSTEMSOFTHE3AN*OAQUIN"ASIN0ROVINCEˆ'EOCHEMICAL#HARACTERISTICSOF'AS4YPES 29 5 C 13 2 CO 13 4

-C n 13 4

-C i 13 3 C 13 2 D C 2 C 13 1 D C 1 C

13

wetness benzene 7

-C n 6

-C n - 5 C neo 5

-C n 5

-C i 4 ------43.04 --- -30.29 --- -27.02 --- -25.32 -8.73 -25.14 ------0.03 --- 0.02 0.02 ------0.08 --- 3.40 -57.02 --- -45.34 ------29.65 ------1.16 --- -53.38 -26.10 1.19 -25.15 ------40.36 12.81 ------­ --- -21.50 ------0.06 ------67.99 ------­ ------15.22 --- --­ ------­ ------­ 2.4 0.56 0.47 --- 0.05 0.03 0.05 14.21 -56.62 ------­ -C % % % % % % % % ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ ‰ 4.08 0.71 0.51 --- 0.17 0.04 --- 36.20 -46.77 0.05 --- -31.82 ------27.98 -27.61 -22.92 ------­ --- 6.15 -31.22 --- -22.87 ------­ 0.35 0.03 5.23 0.89 --- 0.8 0.75 0.02 --- 0.37 0.27 0.21 0.08 0.11 0.02 ------37.14 --- 0.02 -37.73 ------12.69 ------30.28 0.36 -39.75 0.02 4.80 ------53.52 -29.25 6.41 -27.51 --- -26.16 -25.67 --- 0.06 5.06 ------0.73 --- -26.33 -24.76 2.17 0.05 8.39 --- 0.68 -40.59 --- 1.97 ------1.61 0.09 1.36 -28.03 ------30.13 --­ --- -24.41 0.6 --- 0.16 -33.72 ------0.49 ------30.06 6.08 --- -49.51 --- -51.13 ------20.86 --­ -55.48 ------­ -26.57 --- 31.31 --- -54.97 --- -28.96 ------17.38 -26.13 --- -21.75 --- -38.20 --- -19.80 -29.78 --- -28.38 -155 -28.09 -26.80 -24.40 -134 ------24.70 --- -24.80 -28.87 --- -23.30 -27.44 --- -23.21 --­ --­ -5.92 ------­ --­ --­ ------­ 1.85 0.781 0.554 1.54 0.457 0.326 ---2.14 0.739 0.611 ------14.83 --- -49.90 17.75 --- -198 -35.60 -29.50 20.28 -128 -153 -26.70 -40.00 -27.60 -126 -163 -25.50 -28.40 -133 --- -26.20 -25.00 --- -23.20 ------­ --- --­ --­ 0.001 0.001 0.001 ------0.04 -70.20 -203 ------13.10 --­ n Field Name Additional geochemical data of natural gas samples from the San Joaquin Basin Province, California—Continued. Wheeler Ridge 68 Semitropic 75 76 Tejon, North Trico 81 wildcat well 59 Paloma 60 61 Paloma 62 Pyramid Hills 63 Pyramid Hills 64 Raisin City 65 Raisin City 66 Raisin City 67 Rosedale Ranch San Joaquin 69 70 Semitropic 71 Semitropic 72 Stockdale 73 Stockdale 74 Stockdale Tejon, North 77 78 Van Ness Slough 79 Wheeler Ridge 80 Wheeler Ridge 2.56 0.38 0.27 ------23.39 -48.11 --- -31.01 --- -29.98 ------­ Gas Sample Number Table 10.2 B . Table 30 Petroleum Systems and Geologic Assessment of Oil and Gas in the San Joaquin Basin Province, California

Table 10.3 Definition of gas types, San Joaquin Basin Province, California

C 1 Stable Carbon Isotopes, ‰ Wetness 0 to 2.5% Wetness >2.5% 13 C > –45 TD TW 13 C –55 to –45 TD-Mixed TW-Mixed 13 C <–55 B TW-Mixed

TD = thermogenic dry, TW = thermogenic wet, B = biogenic, mixed = mixture of biogenic and thermogenic gas.

Wetness = percent C2+ or [(ΣC2 to C5)/(ΣC1 to C5)] * 100.