Geochemical constraints on the hydrocarbon generation and expulsion in source rocks with different primary organic matter compositions: A case study on the Lucaogou Formation in the Jimusaer Sag, Junggar Basin, Northwest China

Organic Geochemistry, Journal Year: 2025, Volume and Issue: 202, P. 104952 - 104952

Published: Feb. 16, 2025

Language: Английский

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Unconventional Petroleum Sedimentology: A Key to Understanding Unconventional Hydrocarbon Accumulation

Engineering, Journal Year: 2022, Volume and Issue: 18, P. 62 - 78

Published: Aug. 6, 2022

The commercial exploitation of unconventional petroleum resources (e.g., shale oil/gas and tight oil/gas) has drastically changed the global energy structure within past two decades. Sweet-spot intervals (areas), most prolific hydrocarbon resources, generally consist extraordinarily high organic matter (EHOM) deposits or closely associated sandstones/carbonate rocks. formation sweet-spot (areas) is fundamentally controlled by their depositional subsequent diagenetic settings, which result from coupled sedimentation regional geological events, such as tectonic activity, sea level (lake level) fluctuations, climate change, bottom water anoxia, volcanic biotic mass extinction radiation, gravity flows during a certain period. Black shales with EHOM content high-quality reservoir rocks deposited coupling major events provide not only prerequisite for massive generation but also abundant storage space. Ordovician–Silurian Wufeng–Longmaxi Sichuan Basin, Devonian Marcellus Appalachian Devonian–Carboniferous Bakken Formation Williston Triassic Yanchang Ordos Basin are four typical systems selected case studies herein. In each case, was different collectively resulting in favorable environment production, preservation, accumulation matter, well generation, migration, accumulation, hydrocarbons. Unconventional sedimentology, focuses on dramatic environmental changes driven key to improve understanding distribution systems.

Language: Английский

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Oceanic anoxic events, photic-zone euxinia, and controversy of sea-level fluctuations during the Middle-Late Devonian

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 241, P. 104415 - 104415

Published: April 10, 2023

Language: Английский

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Decreased marine organic carbon burial during the Hirnantian glaciation

Earth and Planetary Science Letters, Journal Year: 2025, Volume and Issue: 654, P. 119240 - 119240

Published: Jan. 30, 2025

Language: Английский

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Difference analysis of shale gas-bearing property —a case study of the shale within lower Cambrian Niutitang Formation on the margin of palaeouplift

Frontiers in Earth Science, Journal Year: 2025, Volume and Issue: 13

Published: Feb. 19, 2025

Introduction Shale gas has become an important field for increasing oil and reserves production in China. The breakthrough of Cambrian shale Sichuan Basin provides guidance the exploration southern However, Niutitang Formation on periphery exhibits multiple depositional subfacies complex structural styles, factors diversity are not clear. Methods By methods organic geochemistry experiment, reservoir physical property test content test, combined with hydrocarbon generation history evolution data, difference is analyzed Hannan palaeouplift, Shennongjia Huangling palaeouplift Xuefengshan palaeouplift. Results matter type mainly I, average carbon 1.50%–3.56%, R o 2.37%–3.90%, brittle minerals quartz that 28%–53%, porosity 0.51%–3.34%. pores contain pores, inorganic micro-fractures, fractures mostly filled calcite. Gas 0.13m³/t–4.19m³/t. Through comparative analysis main controlling affecting shale, causes identified. Discussion (1) differences preservation conditions caused by strength, fracture development degree coupling relationship tectonic key restricting shale. (2) Early deep burial time, long time fast cause thermal (3) potential sedimentary same facies zone factor capacity (4) areas lower Plate thrust nappe, less than 3.0%, deepwater trough favorable directions further exploration. This study will reference significance area south

Language: Английский

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Revisiting paleoenvironmental changes on the Upper Yangtze Block during the Ordovician-Silurian transition: New insights from elemental geochemistry

Sedimentary Geology, Journal Year: 2023, Volume and Issue: 450, P. 106377 - 106377

Published: April 4, 2023

Language: Английский

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Linking carbon cycle perturbations to the Late Ordovician glaciation and mass extinction: A modeling approach

Earth and Planetary Science Letters, Journal Year: 2024, Volume and Issue: 631, P. 118635 - 118635

Published: March 2, 2024

Language: Английский

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Productivity and redox influences on the late Ordovician ‘Katian Extinction’ and ‘early Silurian Recovery’

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2024, Volume and Issue: 642, P. 112176 - 112176

Published: March 30, 2024

Language: Английский

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Enrichment Mechanism of Helium in the Jiaoshiba Shale Gas Field, Sichuan Basin, SW China

Geological Journal, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 21, 2025

ABSTRACT In Sichuan Basin, uranium (U) and thorium (Th) are more abundant in organic‐rich shale than granitic rocks, suggesting that is a significant source rock for helium (He). However, the He generation potential of enrichment mechanisms gas fields remain limited understanding. Based on He, U Th concentration tests, fluid inclusion analysis Jiaoshiba field, it was found concentrations 340–730 ppm. The helium‐rich (≥ 500 ppm) primarily synclinal units. biggest abundance area (0.27 m 3 /m 2 ) located at core anticline. not solely derived from Wufeng–Longmaxi itself, current (0.15–0.27 exceeds its historical intensity (0.063–0.104 calculated by shale. Low‐angle deep faults favourable capture high‐angle faults. hydrocarbon 21,851–29,224 times greater which indicates dilution to significantly common rocks (3000 times). model study includes three stages: continuous burial, fold‐dominated, fault‐dominated stages. anticline zone, continuously accumulated as carrier migration. syncline mainly migration along water flows aquifer, stage. He‐rich preferentially shallow reservoirs associated with faults, layers zones adjacent low‐angle

Language: Английский

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Mercury evidences link intensive volcanism to the Late Ordovician mass extinction and changes in the atmosphere-land-ocean system

The Innovation Geoscience, Journal Year: 2025, Volume and Issue: unknown, P. 100124 - 100124

Published: Jan. 1, 2025

<p>The Late Ordovician mass extinction (LOME, ca. 445 Ma), which occurred over two intervals (LOMEI-1 and LOMEI-2), was the first “Big Five” biotic crises of Phanerozoic. The ultimate trigger this remains debated, with glacially induced global cooling volcanism-driven warming events separately suggested as underlying cause. Here, we report anomalously high mercury (Hg) levels in Ordovician-Silurian successions from a shelf-to-slope transect South China, indicating abnormally Hg loading to ocean. Analyses isotopes through reveal near-zero Δ¹⁹⁹Hg late Katian earliest Hirnantian (LOMEI-1), suggesting that mainly derived large-scale volcanism. Positive shifts are observed during stage, coincident glaciation, enhanced sequestration sediments driven by subsidence cold dense surface seawater. Negative values across LOMEI-2 within likely suggest terrestrial sulfate fluxes ocean due volcanism-induced warming, promoted oceanic anoxic/euxinic conditions. This study provides novel evidences linking intensive volcanism significant changes atmosphere-land-ocean system transition, particularly euxinic conditions triggered LOME.</p>

Language: Английский

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