Paleoenviromental Reconstruction and Organic Matter Accumulation Mechanism for Youganwo Formation Oil Shale in Maoming Basin

被引：1

作者：

Cao, Taotao ^{[1
]}

Liu, Hu ^{[2
,3
]}

Xiao, Juanyi ^{[1
]}

Pan, Anyang ^{[4
]}

Deng, Mo ^{[4
]}

机构：

[1] School of Earth Sciences and Spatial Information Engineering, Hunan University of Science and Technology, Xiangtan

[2] Sichuan Key Laboratory of Shale Gas Evaluation and Exploration, Chengdu

[3] Sichuan Institute of Geological Survey, Chengdu

[4] Wuxi Research Institute of Petroleum Geology, Petroleum Exploration＆ Production Research Institute, SINOPEC, Wuxi

来源：

Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | 2024年 / 49卷 / 04期

关键词：

geochemistry; Maoming basin; oil shale; organic matter accumulation; paleo environment; petroleum geology; Youganwo Formation;

D O I：

10.3799/dqkx.2022.260

中图分类号：

学科分类号：

摘要：

To identify the formation background of oil shale and the enrichment mechanism of high-quality intervals are the fundamental works for in-situ upgrading of oil shale reservoir. In this paper, geochemical methods, e.g., TOC, major and trace element, rare earth element and biomarkers, were carried out to restore paleosedimentary environment as well as discuss organic matter accumulation mechanism. The results suggest that oil shale within the entire interval of Youganwo Formation is rich in organic matter, and the bottom is composed of thin carbonaceous shale, sandstone and lignite. Mo content, Ba/Al, Babio and biomarkers all reflect that Youganwo Formation has high primary productivity, with intermittent“algal bloom”phenomenon. V/(V+Ni), Ceanom, Th/U, pyrite framboids and Pr/nC17-Ph/nC18 crossplot indicate that Youganwo Formation was anoxic environment. Sr/Cu, Rb/Sr and climate index C identify that the climate of Youganwo Formation was warm and humid. Sr/Ba, Ba/Ga, Ca/(Fe+Ca), Al2O3/MgO and gammacerane feature suggest that water of ancient lake is fresh. The ancient lake of Youganwo Formation was semi-deep to deep, proved by Zr/Al, Rb/K and MnO content. Through the correlations between paleo-environmental parameters with TOC content, it is deemed that the warm and humid climate and freshwater environment can provide good conditions for the flourishing of algae, forming high quality productivity, and therefore it determines the quality and development characteristics of Youganwo Formation oil shale. High primary productivity with abundant organic matter sources is the main condition for oil shale formation, and anoxic semi-deep to deep lake environment, as a promoting factor, is conducive to organic matter accumulation and preservation. To sum up, in this paper it proposes the accumulation model of organic matter in high-quality oil shale of Youganwo Formation in the Maoming Basin. © 2024 China University of Geosciences. All rights reserved.

引用

页码：1367 / 1384

页数：17

共 50 条

[1]

Algeo T. J., Henderson C. M., Tong J. N., Et al., Plankton and Productivity during the Permian-Triassic Boundary Crisis: An Analysis of Organic Carbon Fluxes, Global and Planetary Change, 105, 6, pp. 52-67, (2013)

[2]

Cao X.X., Song Z.G., Li Y., Et al., The Characteristics of Organic Matter in Maoming Oil Shales and Their Paleoclimate Significance, Earth Science Fron⁃ tiers, 23, 3, pp. 243-252, (2016)

[3]

Guo W., Feng Q. L., Khan M.Z., Organic Matter Enrichment Mechanism of Black Shale in Wufeng-Longmaxi Formations: A Case Study from Jiaoye 143-5 Well at Chongqing, Earth Science, 46, 2, pp. 572-582, (2021)

[4]

He L., Wang Y. P., Chen D. F., Et al., Relationship between Sedimentary Environment and Organic Matter Accumulation in the Black Shale of Wufeng-Longmaxi Formations in Nanchuan Area, Chongqing, Natural Gas Geoscience, 30, 2, pp. 203-218, (2019)

[5]

Hou L.Y., Sun P.C., Liu Z.J., Et al., Qingshankou Formation Oil Shale Exploitation In-Situ Pilot Test Demonstration Area Optimization, Coal Geology of Chi⁃ na, 33, 8, pp. 9-16, (2021)

[6]

Hu X.F., Liu Z.J., Liu R., Et al., Clay Mineral and Inorganic Geochemical Characteristics of Eocene Huadian Formation in Huadian Basin and Their Paleoenvironment Implications, Journal of China Coal Society, 37, 3, pp. 416-423, (2012)

[7]

Jin Z. D., Zhang E. L., Paleoclimate Implication of Rb/Sr Ratios from Lake Sediments, Science Technology and Engineering, 2, 3, pp. 20-22, (2002)

[8]

Kang Z. Q., Zhao Y. S., Yang D., Et al., Pilot Test of In-Situ Steam Injection for Oil and Gas Production from Oil Shale and Applicability of Multi-Mode In-Situ Thermal Recovery Technology, Acta Petrolei Sini⁃ ca, 42, 11, pp. 1458-1468, (2021)

[9]

Kuypers M. M. M., Pancost R. D., Nijenhuis I. A., Et al., Enhanced Productivity Led to Increased Organic Carbon Burial in the Euxinic North Atlantic Basin during the Late Cenomanian Oceanic Anoxic Event, Pa⁃ leoceanography, 17, 4, (2002)

[10]

Li D.C., Zhu J.W., Yan H.R., Et al., Sedimentary Characteristics and Distribution Rule of Oil Shale in Maoming Basin in Guangdong Province, Journal of Jilin University (Earth Science Edition), 36, 6, pp. 938-943, (2006)

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