Geochemical Criteria for Possible Identification of Hydrocarbons Generated by Upper Proterozoic Source Rock

Mapping Intimacies ◽

10.17072/chirvinsky.2021.103 ◽

2021 ◽

Author(s):

D.D. Kozhanov ◽

◽

I.S. Khopta ◽

Keyword(s):

Organic Matter ◽

Source Rock ◽

Geochemical Conditions ◽

Upper Proterozoic ◽

Key Points ◽

Original Organic Matter

The article summarizes the literature data of domestic and foreign researchers on the geological and geochemical conditions of the formation and transformation of the original organic matter of ancient Upper Proterozoic strata, as well as key points in understanding the processes of their accumulation at the R-V boundary.

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Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin, China

Petroleum Science ◽

10.1007/s12182-021-00554-1 ◽

2021 ◽

Vol 18 (2) ◽

pp. 398-415

Author(s):

He Bi ◽

Peng Li ◽

Yun Jiang ◽

Jing-Jing Fan ◽

Xiao-Yue Chen

Keyword(s):

Organic Matter ◽

Source Rock ◽

Thermal Evolution ◽

Songliao Basin ◽

Source Rocks ◽

Crude Oils ◽

Western Slope ◽

Geochemical Parameters ◽

Group I ◽

Oil Source

AbstractThis study considers the Upper Cretaceous Qingshankou Formation, Yaojia Formation, and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin. Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area. To evaluate their development characteristics, differences and effectiveness, geochemical parameters are analyzed. One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks. Through the biomarker characteristics, the source–source, oil–oil, and oil–source correlations are assessed and the sources of crude oils in different rock units are determined. Based on the results, Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton, respectively. Gulong source rock has higher thermal evolution degree than Qijia source rock. The biomarker parameters of the source rocks are compared with 31 crude oil samples. The studied crude oils can be divided into two groups. The oil–source correlations show that group I oils from Qing II–III, Yao I, and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock.

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Source rock characterization of mesozoic to cenozoic organic matter rich marls and shales of the Eratosthenes Seamount, Eastern Mediterranean Sea

Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles ◽

10.2516/ogst/2018036 ◽

2018 ◽

Vol 73 ◽

pp. 49 ◽

Cited By ~ 8

Author(s):

Sebastian Grohmann ◽

Susanne W. Fietz ◽

Ralf Littke ◽

Samer Bou Daher ◽

Maria Fernanda Romero-Sarmiento ◽

...

Keyword(s):

Organic Matter ◽

Mediterranean Sea ◽

Source Rock ◽

Eastern Mediterranean ◽

Source Rocks ◽

Eastern Mediterranean Sea ◽

Potential Source Rock ◽

Levant Basin ◽

Rock Characterization ◽

Rock Eval

Several significant hydrocarbon accumulations were discovered over the past decade in the Levant Basin, Eastern Mediterranean Sea. Onshore studies have investigated potential source rock intervals to the east and south of the Levant Basin, whereas its offshore western margin is still relatively underexplored. Only a few cores were recovered from four boreholes offshore southern Cyprus by the Ocean Drilling Program (ODP) during the drilling campaign Leg 160 in 1995. These wells transect the Eratosthenes Seamount, a drowned bathymetric high, and recovered a thick sequence of both pre- and post-Messinian sedimentary rocks, containing mainly marine marls and shales. In this study, 122 core samples of Late Cretaceous to Messinian age were analyzed in order to identify organic-matter-rich intervals and to determine their depositional environment as well as their source rock potential and thermal maturity. Both Total Organic and Inorganic Carbon (TOC, TIC) analyses as well as Rock-Eval pyrolysis were firstly performed for the complete set of samples whereas Total Sulfur (TS) analysis was only carried out on samples containing significant amount of organic matter (>0.3 wt.% TOC). Based on the Rock-Eval results, eight samples were selected for organic petrographic investigations and twelve samples for analysis of major aliphatic hydrocarbon compounds. The organic content is highly variable in the analyzed samples (0–9.3 wt.%). TS/TOC as well as several biomarker ratios (e.g. Pr/Ph < 2) indicate a deposition under dysoxic conditions for the organic matter-rich sections, which were probably reached during sporadically active upwelling periods. Results prove potential oil prone Type II kerogen source rock intervals of fair to very good quality being present in Turonian to Coniacian (average: TOC = 0.93 wt.%, HI = 319 mg HC/g TOC) and in Bartonian to Priabonian (average: TOC = 4.8 wt.%, HI = 469 mg HC/g TOC) intervals. A precise determination of the actual source rock thickness is prevented by low core recovery rates for the respective intervals. All analyzed samples are immature to early mature. However, the presence of deeper buried, thermally mature source rocks and hydrocarbon migration is indicated by the observation of solid bitumen impregnation in one Upper Cretaceous and in one Lower Eocene sample.

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Origin of organic matter from tectonic zones in the Western Tatra Mountains Crystalline Basement, Poland: An example of bitumen—source rock correlation

Marine and Petroleum Geology ◽

10.1016/j.marpetgeo.2005.08.001 ◽

2006 ◽

Vol 23 (2) ◽

pp. 261-279 ◽

Cited By ~ 10

Author(s):

Leszek Marynowski ◽

Aleksandra Gawe¸da ◽

Paweł Poprawa ◽

Michał M. Zywiecki ◽

Beata Ke¸pińska ◽

...

Keyword(s):

Organic Matter ◽

Source Rock ◽

Crystalline Basement ◽

Tatra Mountains ◽

Tectonic Zones

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Synthesis of organic matter composition and maturation and gas data from selected deep source rock units for some wells in the Fox Creek area

10.4095/328238 ◽

2021 ◽

Author(s):

D Lavoie ◽

O H Ardakani ◽

C Rivard

Keyword(s):

Organic Matter ◽

Source Rock ◽

Organic Matter Composition ◽

Deep Source

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Liquid hydrocarbon characterization of the lacustrine Yanchang Formation, Ordos Basin, China: Organic-matter source variation and thermal maturity

Interpretation ◽

10.1190/int-2016-0114.1 ◽

2017 ◽

Vol 5 (2) ◽

pp. SF225-SF242 ◽

Cited By ~ 2

Author(s):

Xun Sun ◽

Quansheng Liang ◽

Chengfu Jiang ◽

Daniel Enriquez ◽

Tongwei Zhang ◽

...

Keyword(s):

Organic Matter ◽

Source Rock ◽

Ordos Basin ◽

Depositional Environments ◽

Source Rocks ◽

Type I ◽

Hydrocarbon Generation ◽

Type Ii ◽

Thermal Maturity ◽

Yanchang Formation

Source-rock samples from the Upper Triassic Yanchang Formation in the Ordos Basin of China were geochemically characterized to determine variations in depositional environments, organic-matter (OM) source, and thermal maturity. Total organic carbon (TOC) content varies from 4 wt% to 10 wt% in the Chang 7, Chang 8, and Chang 9 members — the three OM-rich shale intervals. The Chang 7 has the highest TOC and hydrogen index values, and it is considered the best source rock in the formation. Geochemical evidence indicates that the main sources of OM in the Yanchang Formation are freshwater lacustrine phytoplanktons, aquatic macrophytes, aquatic organisms, and land plants deposited under a weakly reducing to suboxic depositional environment. The elevated [Formula: see text] sterane concentration and depleted [Formula: see text] values of OM in the middle of the Chang 7 may indicate the presence of freshwater cyanobacteria blooms that corresponds to a period of maximum lake expansion. The OM deposited in deeper parts of the lake is dominated by oil-prone type I or type II kerogen or a mixture of both. The OM deposited in shallower settings is characterized by increased terrestrial input with a mixture of types II and III kerogen. These source rocks are in the oil window, with maturity increasing with burial depth. The measured solid-bitumen reflectance and calculated vitrinite reflectance from the temperature at maximum release of hydrocarbons occurs during Rock-Eval pyrolysis ([Formula: see text]) and the methylphenanthrene index (MPI-1) chemical maturity parameters range from 0.8 to [Formula: see text]. Because the thermal labilities of OM are associated with the kerogen type, the required thermal stress for oil generation from types I and II mixed kerogen has a higher and narrower range of temperature for hydrocarbon generation than that of OM dominated by type II kerogen or types II and III mixed kerogen deposited in the prodelta and delta front.

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THE ORIGINS OF COASTAL BITUMENS FROM WESTERN AUSTRALIA

The APPEA Journal ◽

10.1071/aj93059 ◽

1994 ◽

Vol 34 (1) ◽

pp. 787

Author(s):

R. Alexander ◽

T.J. Currie ◽

R.I. Kagi

Keyword(s):

Organic Matter ◽

Crude Oil ◽

Source Rock ◽

Western Australia ◽

Se Asia ◽

Indonesian Archipelago ◽

Organic Matter Type ◽

Oil Seep ◽

Australian Coastline ◽

Depositional Setting

A total of 83 samples of stranded bitumens collected from the western and southern coasts of Western Australia have been classified into eight groups on the basis of their biomarker compositions. The source rock characteristics inferred for these bitumens, in terms of organic matter type and depositional setting indicated by the biomarkers, suggest strongly that the bitumens originate from a variety of areas in SE Asia in the vicinity of the Indonesian archipelago. In fact, in seven of the eight cases a good correlation is observed between biomarker composition of each bitumen group and a produced crude oil or oil seep from this region. The bitumens are transported to and around the Australian coastline by a system of ocean currents.

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Organic geochemical and palynological studies of the Maastrichtian source rock intervals in Bida Basin, Nigeria: implications for hydrocarbon prospectivity

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-020-00989-z ◽

2020 ◽

Vol 10 (8) ◽

pp. 3191-3206

Author(s):

Olusola J. Ojo ◽

Ayoola Y. Jimoh ◽

Juliet C. Umelo ◽

Samuel O. Akande

Keyword(s):

Organic Matter ◽

Source Rock ◽

Vitrinite Reflectance ◽

Source Rocks ◽

High Yield ◽

Thermal Maturity ◽

Hydrocarbon Source Rock ◽

Moderate Amount ◽

Oxic Condition ◽

Freshwater Swamp

Abstract The Patti Formation which consists of sandstone and shale offers the best potential source beds in the Bida Basin. This inland basin is one of the basins currently being tested for hydrocarbon prospectivity in Nigeria. Fresh samples of shale from Agbaja borehole, Ahoko quarry and Geheku road cut were analysed using organic geochemical and palynological techniques to unravel their age, paleoecology, palynofacies and source bed hydrocarbon potential. Palynological data suggest Maastrichtian age for the sediments based on the abundance of microfloral assemblage; Retidiporites magdalenensis, Echitriporites trianguliformis and Buttinia andreevi. Dinocysts belonging to the Spiniferites, Deflandrea and Dinogymnium genera from some of the analysed intervals are indicative of freshwater swamp and normal sea conditions. Palynological evidence further suggests mangrove paleovegetation and humid climate. Relatively high total organic carbon TOC (0.77–8.95 wt%) was obtained for the shales which implies substantial concentration of organic matter in the source beds. Hydrocarbon source rock potential ranges from 0.19 to 0.70 mgHC/g.rock except for a certain source rock interval in the Agbaja borehole with high yield of 25.18 mgHC/g.rock. This interval also presents exceptionally high HI of 274 mgHC/g.TOC and moderate amount of amorphous organic matter. The data suggests that in spite of the favourable organic matter quantity, the thermal maturity is low as indicated by vitrinite reflectance and Tmax (0.46 to 0.48 Ro% and 413 to 475 °C, respectively). The hydrocarbon extracts show abundance of odd number alkanes C27–C33, low sterane/hopane ratio and Pr/Ph > 2. We conclude that the source rocks were terrestrially derived under oxic condition and dominated by type III kerogen. Type II organic matter with oil and gas potential is a possibility in Agbaja area of Bida Basin. Thermal maturity is low and little, or no hydrocarbon has been generated from the source rocks.

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