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Formation environments and mechanisms of multistage paleokarst of Ordovician carbonates in Southern North China Basin [PDF]
Scientific Reports, 2021 With the reduction of oil and gas reserves and the increase of mining difficulty in Northern China, the carbonate rocks in Southern North China Basin are becoming a significant exploration target for carbonate reservoirs.
Haitao Zhang +3 more
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Porosity and permeability of karst carbonate rocks along an unconformity outcrop: A case study from the Upper Dammam Formation exposure in Kuwait, Arabian Gulf [PDF]
Heliyon, 2021 Diagenetic changes are a concern in carbonate petroleum reservoir management. One of the challenges is to determine whether the pore systems are related to diagenesis and/or depositions, and how associated mechanisms affect reservoir quality. The purpose
Fowzia H. Abdullah
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Stable isotopic evidence for increased terrestrial productivity through geological time [PDF]
Scientific ReportsMarine life on Earth is known back to the Archean Eon, when life on land is assumed to have been less pervasive than now. Precambrian life on land can now be tested with stable isotopes because living soil CO2 is isotopically distinct for both carbon and
Gregory J. Retallack, Ilya N. Bindeman
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The first hominin from the early Pleistocene paleocave of Haasgat, South Africa [PDF]
PeerJ, 2016 Haasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered ...
AB Leece +7 more
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Speleogenesis and depositional history of paleokarst phreatic caves/cavities; Podgrad, SW Slovenia
Acta Carsologica, 2021 The studied paleokarst corresponds to an uplifted peripheral foreland bulge when Upper Cretaceous diagenetically immature eogenetic carbonates were subaerially exposed, karstified and subsequently overlain by upper Paleocene/lower Eocene palustrine ...
Bojan Otoničar
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Frontiers in Earth Science, 2022 As a special type of fracture-cavity carbonate reservoir, fault/fracture-controlled paleokarsts are affected by large strike-slip faults with various storage spaces, irregular geometry, and stochastic spatial distribution, which brings new challenges to ...
Wenbiao Zhang +6 more
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Petroleum Exploration and Development, 2021 Based on analysis of outcrop, drilling, logging and seismic data, and geotectonic background, the lithofacies paleogeography and paleokarst geomorphology of the Middle Permian Maokou Formation in the northwestern Sichuan Basin were reconstructed, and the
Yuan ZHONG +9 more
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Research progress of paleokarst oil and gas reservoirs
Carsologica Sinica, 2022 The transformation of soluble rocks by paleokarst can form dissolution pores and other reservoir spaces. Especially for carbonate rocks, the development of paleokarst can greatly improve the reservoir performance of the formation and form karst ...
Yu ZHANG +3 more
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Upper Ordovician hardgrounds – from localized surfaces to global biogeochemical events [PDF]
Estonian Journal of Earth Sciences, 2023 Upper Ordovician hardgrounds display a spectrum of complexity reflecting a range of local to global-scale processes. Hardgrounds are cemented seafloor surfaces typically marked by the presence of encrusting taxa and borings.
Timothy R. Paton +4 more
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Shiyou shiyan dizhi, 2023 In recent years, some progress has been made in the exploration of Ordovician natural gas in the western Ordos Basin, among which, the Ordovician Kelimoli Formation has the highest degree of natural gas accumulation.
Huimin LI +7 more
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