Results 11 to 20 of about 342 (179)
Automated graptolite identification at high taxonomic resolution using residual networks [PDF]
iScienceSummary: Graptolites, fossils significant for evolutionary studies and shale gas exploration, are traditionally identified visually by taxonomists due to their intricate morphologies and preservation challenges.
Zhi-Bin Niu, Si-Yuan Jia, Hong-He Xu
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Petroleum Exploration and Development, 2016 Multiple tests were conducted on graptolite shale samples from Middle Ordovician Pingliang Formation in three typical areas in Ordos Basin to investigate the relationship between micro-nano pore structure, graptolite content, rock composition, TOC ...
Hucheng Deng, , Lifa Zhou
exaly +3 more sources
Influence of quartz types on mechanical parameters in the early silurian Longmaxi shale, Sichuan Basin [PDF]
Scientific ReportsQuartz is one of the most abundant minerals in shales, occurring predominantly in three forms: biogenic quartz (BQ), detrital quartz (DQ) and clay-transformed quartz (CTQ).
Qin Zhang +9 more
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Characteristics of three organic matter pore types in the Wufeng-Longmaxi Shale of the Sichuan Basin, Southwest China [PDF]
Scientific Reports, 2018 A consensus has been reached through previous studies that organic matter (OM) pores are crucial to porosity in many shale gas reservoirs; however, their origins and types remain controversial.
Haikuan Nie, Zhijun Jin, Jinchuan Zhang
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Monopodial and Sympodial Growth Modes in the Colonial Graptolithina (Hemichordata, Pterobranchia). [PDF]
Evol DevABSTRACT Two growth modes are recognized in colonial pterobranchs (Graptolithina): monopodial growth and sympodial growth. The earliest colonial Graptolithina likely developed through monopodial growth, a mode of colony formation well‐documented in the extant graptolite Rhabdopleura normani.
Maletz J, Lerosey-Aubril R.
europepmc +2 more sources
Biogeographic dynamics of graptolite species during the end-Ordovician mass extinction in South China [PDF]
Estonian Journal of Earth Sciences, 2023 Spatial and temporal analysis of geographical biodiversity dynamics and reconstruction of species distribution areas are essential for revealing the patterns of evolution of graptolites and their survival strategies during bio-events.
Qing Chen, Linna Zhang
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Energies, 2022 Graptolite-rich shale is the main layer of shale gas resources in the southern marine sedimentary basin. Recently, shale gas resources were discovered in the Ordovician marine graptolite-rich strata in the Ordos Basin.
Fengjiao Li +8 more
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A new species of the problematic organism Webbyites from the Early Ordovician Fezouata Biota of Morocco [PDF]
Estonian Journal of Earth Sciences, 2023 The problematic colonial organism Webbyites has previously been considered to be a hydroid (phylum Cnidaria). In this paper, we describe a new species, Webbyites felix sp. nov., from the Early Ordovician Fezouata Konservat-Lagerstätte of Morocco.
Lucy A. Muir +1 more
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Tremadocian (Ordovician) reclined graptolites from Baishan, North China [PDF]
Estonian Journal of Earth Sciences, 2023 The Erdaopuzi section in the Baishan area of Jilin Province, northeast China, contains abundant late Tremadoc graptolites. However, there are some taxonomic controversies regarding the characters of the hand specimens that are difficult to identify.
Ming Li +3 more
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Petroleum Exploration and Development, 2021 Through graptolite identification in profiles, graptolite zone division, contour map compilation, and analysis of mineral composition, TOC content, lamina distribution features of shale samples, the biostratigraphic and reservoir characteristics of ...
Hongyan WANG, Zhensheng SHI, Shasha SUN
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