Thermal Evolution and Hydrocarbon Generation Capacity of Typical Palaeozoic Marine Source Rocks in the South China Craton: Constrains from Semiclosed Artificial Thermal Maturation Experiments

Palaeozoic petroleum systems in the South China craton are prospecting frontiers for unconventional oil/gas. Understanding the hydrocarbon generation/retention capacity of source rocks has critical implications for reserve evaluation and targeting, which yet remains ambiguous in this region. In this study, six representative lithological types of organic-rich, immature-low-mature source rocks (two shales, two carbonates, a coal, and a solid bitumen) taken from the South China craton were treated with semiclosed hydrous pyrolysis (300–550°C). Pyrolysis results show that shale and carbonate source rocks have great hydrocarbon generation capacities, and immature solid bitumen can also generate appreciable quantities of hydrocarbons, whereas coal has the least hydrocarbon generation capacity. Both oil and gas are important hydrocarbon products of thermal maturation of shales, whereas gas generation capacity of carbonate source rocks is relatively moderate compared to their oil generation capacity. Therefore, marine shale is an important exploration target for unconventional oil and gas, yet marine carbonate is an important target for unconventional oils. The presence of appreciable carbonate minerals in shales can facilitate oil and gas generation likely by (1) enhancing oil expulsion, (2) facilitating decarboxylation of organic acid, and (3) catalysis. Pyrolysis data also support that molecular composition of thermogenic gas is not dominantly controlled by lithofacies of source rocks but mainly affected by maturation. Outcomes of this study demonstrate that marine organic-rich rocks within the Palaeozoic strata in the South China craton are critical prospecting targets for unconventional oil and gas.

[1]  Xiaowen Guo,et al.  Carbon-hydrogen isotopic systematics of gases generated in semi-closed hydrous pyrolysis of type I source rock with the presence of formation water: Implications for gas isotope partitioning under supercritical conditions , 2022, Marine and Petroleum Geology.

[2]  Xiaowen Guo,et al.  Semi-closed artificial thermal maturation of type I source rock with the presence of natural formation water: Hydrocarbon generation and individual n-alkane stable carbon isotope partitioning pattern , 2022, Marine and Petroleum Geology.

[3]  Ru-yi Wang,et al.  Elemental geochemical evidence for controlling factors and mechanisms of transitional organic matter accumulation: The upper Permian Longtan Formation black shale in the Lower Yangtze region, South China , 2021, Journal of Natural Gas Science and Engineering.

[4]  Y. Zou,et al.  Hydrocarbon generation characteristics of solid bitumen and molecular simulation based on the density functional theory , 2021, Marine and Petroleum Geology.

[5]  H. Lareau,et al.  Bitumen geochemistry and producibility in the Upper Cretaceous Niobrara Formation shale oil play , 2021, AAPG Bulletin.

[6]  B. Deng,et al.  Early Paleozoic Extension-Compression Transition and Formation of a Paleo-Oil Reservoir System in the NW Sichuan Basin: Implications for Deeply Buried Hydrocarbon Accumulation , 2021 .

[7]  Fengrong Liao,et al.  The role of water during gas generation , 2020, IOP Conference Series: Earth and Environmental Science.

[8]  Wei Li,et al.  Carbonate source rock with low total organic carbon content and high maturity as effective source rock in China: A review , 2019, Journal of Asian Earth Sciences.

[9]  Songtao Wu,et al.  Organic-matter-rich shales of China , 2019, Earth-Science Reviews.

[10]  A. Schimmelmann,et al.  Influence of water hydrogen on the hydrogen stable isotope ratio of methane at low versus high temperatures of methanogenesis , 2019, Organic Geochemistry.

[11]  J. Tong,et al.  Organic matter accumulation on the Dalong Formation (Upper Permian) in western Hubei, South China: Constraints from multiple geochemical proxies and pyrite morphology , 2019, Palaeogeography, Palaeoclimatology, Palaeoecology.

[12]  C. Ballentine,et al.  Determining gas expulsion vs retention during hydrocarbon generation in the Eagle Ford Shale using noble gases , 2018, Geochimica et Cosmochimica Acta.

[13]  G. Etiope,et al.  Revised genetic diagrams for natural gases based on a global dataset of >20,000 samples , 2018, Organic Geochemistry.

[14]  Yuandong Wu,et al.  The effect of pressure and hydrocarbon expulsion on hydrocarbon generation during pyrolyzing of continental type-III kerogen source rocks , 2018, Journal of Petroleum Science and Engineering.

[15]  Jianping Chen,et al.  Gas generation and its isotope composition during coal pyrolysis: Potential mechanism of isotope rollover , 2018, Fuel.

[16]  B. Simoneit,et al.  Molecular markers, carbon isotopes, and rare earth elements of highly mature reservoir pyrobitumens from Sichuan Basin, southwestern China: Implications for PreCambrian-Lower Cambrian petroleum systems , 2018, Precambrian Research.

[17]  B. Simoneit,et al.  Biomarker signatures of Sinian bitumens in the Moxi–Gaoshiti Bulge of Sichuan Basin, China: Geological significance for paleo-oil reservoirs , 2018 .

[18]  Jian Cao,et al.  Hydrocarbon generation capability of Sinian–Lower Cambrian shale, mudstone, and carbonate rocks in the Sichuan Basin, southwestern China: Implications for contributions to the giant Sinian Dengying natural gas accumulation , 2018 .

[19]  Shuichang Zhang,et al.  Pyrolysis involving n-hexadecane, water and minerals: Insight into the mechanisms and isotope fractionation for water-hydrocarbon reaction , 2018 .

[20]  Yuandong Wu,et al.  Hydrocarbon generation and potential in continental organic-rich shales at the highly-mature stage, as determined by hydrous pyrolysis under supercritical conditions , 2018 .

[21]  J. Gardiner,et al.  Geochemical and multi-isotopic ( 87 Sr/ 86 Sr, 143 Nd/ 144 Nd, 238 U/ 235 U) perspectives of sediment sources, depositional conditions, and diagenesis of the Marcellus Shale, Appalachian Basin, USA , 2018 .

[22]  T. Prakoso,et al.  High Selectivity of Alkanes Production by Calcium Basic Soap Thermal Decarboxylation , 2018 .

[23]  M. Rezazadeh,et al.  Unconventional Resources Exploration and Development in the Northern Territory - Challenges from a Regulator's Perspective , 2016 .

[24]  Yanqing Xia,et al.  The effects of pressure and hydrocarbon expulsion on hydrocarbon generation during hydrous pyrolysis of type-I kerogen in source rock , 2016 .

[25]  D. Selby,et al.  Apatite fission-track and Re-Os geochronology of the Xuefeng uplift, China: Temporal implications for dry gas associated hydrocarbon systems , 2016 .

[26]  Mingfeng Zhang,et al.  Organic matter properties and shale gas potential of Paleozoic shales in Sichuan Basin, China , 2016 .

[27]  B. Horsfield,et al.  The Barnett Shale: Compositional fractionation associated with intraformational petroleum migration, retention, and expulsion , 2015 .

[28]  Shuai Yang,et al.  Shale gas potential of the Lower Permian Gufeng Formation in the western area of the Lower Yangtze Platform, China , 2015 .

[29]  Huyue Song,et al.  Marine productivity changes during the end-Permian crisis and Early Triassic recovery , 2015 .

[30]  Jian Cao,et al.  Source characterization of highly mature pyrobitumens using trace and rare earth element geochemistry: Sinian–Paleozoic paleo-oil reservoirs in South China , 2015 .

[31]  Xiaofeng Wang,et al.  Hydrogen isotope characteristics of thermogenic methane in Chinese sedimentary basins , 2015 .

[32]  T. Guo.  The Fuling Shale Gas Field — A highly productive Silurian gas shale with high thermal maturity and complex evolution history, southeastern Sichuan Basin, China , 2015 .

[33]  B. Katz,et al.  Evaluation of Source and Reservoir Properties of Potential Unconventional Units - An Artificial Maturation Approach , 2015 .

[34]  Jaclyn D. Wiggins-Camacho,et al.  Experimental investigation of changes in methane adsorption of bitumen-free Woodford Shale with thermal maturation induced by hydrous pyrolysis , 2015 .

[35]  Jinliang Huang,et al.  Geochemistry of the extremely high thermal maturity Longmaxi shale gas, southern Sichuan Basin , 2014 .

[36]  P. Peng,et al.  The effect of oil expulsion or retention on further thermal degradation of kerogen at the high maturity stage: A pyrolysis study of type II kerogen from Pingliang shale, China , 2014 .

[37]  M. Lewan,et al.  Shale Gas and Oil Potential of Lower Palaeozoic Strata in the Polish Baltic Basin by Hydrous Pyrolysis , 2014 .

[38]  A. Prinzhofer.  Noble Gases in Oil and Gas Accumulations , 2013 .

[39]  Yongfeng Zhu,et al.  The occurrence of ultra-deep heavy oils in the Tabei Uplift of the Tarim Basin, NW China , 2012 .

[40]  Y. Oh,et al.  Decarboxylation of microalgal oil without hydrogen into hydrocarbon for the production of transportation fuel , 2012 .

[41]  Stephen W. Brown,et al.  Isotopic reversal (‘rollover’) in shale gases produced from the Mississippian Barnett and Fayetteville formations , 2012 .

[42]  Daniel M. Jarvie,et al.  Shale Resource Systems for Oil and Gas: Part 1—Shale-gas Resource Systems , 2012 .

[43]  Keyu Liu,et al.  Quantitative estimation of overpressure caused by oil generation in petroliferous basins , 2011 .

[44]  Tongwei Zhang,et al.  Kinetic Model of Gaseous Alkanes Formed from Coal in a Confined System and Its Application to Gas Filling History in Kuqa Depression, Tarim Basin, Northwest China , 2011 .

[45]  Ronald B. Martin,et al.  An Overview of Horizontal-Well Completions in the Haynesville Shale , 2011 .

[46]  Maolong Xia,et al.  High quality source rocks in trough facies of Upper Permian Dalong Formation, Sichuan Basin , 2010 .

[47]  Shenjun Qin,et al.  Early Hydrocarbon Generation of Algae and Influences of Inorganic Environments during Low Temperature Simulation , 2008 .

[48]  Zhen Li,et al.  Catalytic ozonation of phenol in water with natural brucite and magnesia. , 2008, Journal of hazardous materials.

[49]  T. Guo,et al.  Evidence for multiple stages of oil cracking and thermochemical sulfate reduction in the Puguang gas field, Sichuan Basin, China , 2008 .

[50]  Shuichang Zhang,et al.  Petroleum geology of the Puguang sour gas field in the Sichuan Basin, SW China , 2008 .

[51]  C. Pan,et al.  Kerogen Pyrolysis in the Presence and Absence of Water and Minerals. 1. Gas Components , 2008 .

[52]  C. Largeau,et al.  Kerogen origin, evolution and structure , 2007 .

[53]  D. Jarvie,et al.  Unconventional shale-gas systems: The Mississippian Barnett Shale of north-central Texas as one model for thermogenic shale-gas assessment , 2007 .

[54]  A. Schimmelmann,et al.  Hydrogen Isotopic (D/H) Composition of Organic Matter During Diagenesis and Thermal Maturation , 2006 .

[55]  A. Graciaa,et al.  Saturated hydrocarbons occluded inside asphaltene structures and their geochemical significance, as exemplified by two Venezuelan oils , 2006 .

[56]  J. Dai,et al.  Stable carbon isotope compositions and source rock geochemistry of the giant gas accumulations in the Ordos Basin, China , 2005 .

[57]  David R. Brown,et al.  Surface acidities and catalytic activities of acid-activated clays , 2004 .

[58]  Yongchun Tang,et al.  Insights into oil cracking based on laboratory experiments , 2003 .

[59]  M. Lewan,et al.  Comparison of petroleum generation kinetics by isothermal hydrous and nonisothermal open-system pyrolysis , 2002 .

[60]  Oliver C. Mullins,et al.  Gas-Oil Ratio of Live Crude Oils Determined by Near-Infrared Spectroscopy , 2001, SPIE Optics East.

[61]  A. Schimmelmann,et al.  D/H isotope ratios of kerogen, bitumen, oil, and water in hydrous pyrolysis of source rocks containing kerogen types I, II, IIS, and III , 1999 .

[62]  J. Seewald,et al.  Laboratory and theoretical constraints on the generation and composition of natural gas , 1998 .

[63]  L. Stalker,et al.  Biomarker binding into kerogens: evidence from hydrous pyrolysis using heavy water (D2O) , 1998 .

[64]  M. Lewan.  Experiments on the role of water in petroleum formation , 1997 .

[65]  L. Stalker,et al.  Water as an oxygen source for the production of oxygenated compounds (including CO2 precursors) during kerogen maturation , 1994 .

[66]  T. Barth,et al.  Thermal generation of carbon dioxide and organic acids from different source rocks , 1994 .

[67]  T. Schwarzkopf.  Source rock potential (TOC + hydrogen index) evaluation by integrating well log and geochemical data , 1992 .

[68]  W. A. Young,et al.  Expulsion from hydrocarbon sources: the role of organic absorption , 1992 .

[69]  A. Pepper.  Estimating the petroleum expulsion behaviour of source rocks: a novel quantitative approach , 1991, Geological Society, London, Special Publications.

[70]  I. Kaplan,et al.  Role of minerals in the thermal alteration of organic matter--I: generation of gases and condensates under dry condition. , 1985, Geochimica et cosmochimica acta.

[71]  R. Philp.  Petroleum Formation and Occurrence , 1985 .

[72]  M. Lewan.  Evaluation of petroleum generation by hydrous phrolysis experimentation , 1985, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[73]  M. Radke,et al.  Efficiency of petroleum expulsion from shale source rocks , 1984, Nature.

[74]  Martin Schoell,et al.  Genetic Characterization of Natural Gases , 1983 .

[75]  Y. Kharaka,et al.  Thermal decarboxylation of acetic acid: Implications for origin of natural gas , 1983 .

[76]  B. Tissot,et al.  Role of mineral matrix in kerogen pyrolysis; influence on petroleum generation and migration , 1980 .

[77]  M. Lewan,et al.  Generation of Oil-Like Pyrolyzates from Organic-Rich Shales , 1979, Science.

[78]  Y. Kharaka,et al.  Aliphatic Acid Anions in Oil-Field Waters--Implications for Origin of Natural Gas , 1978 .