A new species of trilete zonate miospores, Radiizonates arcuatus, is established for Lower Carboniferous Western Gondwanan forms hitherto ascribed misguidedly to Radiizonates genuinus (Jushko) Loboziak and Alpern (1978), a Russian Lower Carboniferous species. The latter binomen is, moreover, not a valid combination and is more correctly designated as Vallatisporites genuinus (Jushko) Byvsheva, 1980. R. arcuatus is, from records to date, confined to westerly parts of Gondwana (Brazil, North Africa and Middle East), in which it is characteristic of Early Carboniferous strata, albeit with some slightly older and slightly younger occurrences.
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http://dx.doi.org/10.1016/s0034-6667(99)00059-7 | DOI Listing |
Water Res
January 2025
Key Laboratory of Groundwater Conservation of MWR & School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, PR China. Electronic address:
Sulfide mineral oxidation has been recognized as the key driver of arsenic (As) and antimony (Sb) mobility in mining-impacted groundwater. However, the role of carbonate and silicate weathering and secondary mineral precipitation in this process remain unknown. A comprehensive geochemical study of groundwater was conducted in an Sb-mining area, Hunan, China, with samples collected from aquifers of the Xikuangshan Formation (Dx), the Shetianqiao Formation (Ds ), and the Lower Carboniferous Formation (Cy).
View Article and Find Full Text PDFOpen Res Eur
October 2024
National Agency of Hydrocarbon, Bogota, Cundinamarca, 111321, Colombia.
Background: The present contribution reexamines the geometry of a segment of a presumably long-lived fault in Svalbard, the Balliolbreen Fault segment of the Billefjorden Fault Zone, along which presumably two basement terranes of Svalbard accreted in the early-mid Paleozoic after thousands of kilometers strike-slip displacement.
Methods: We performed structural fieldwork to Billefjorden in central Spitsbergen and interpreted satellite images.
Results: Field observations demonstrate that the Balliolbreen Fault formed as a top-west thrust fault in the early Cenozoic and that weak sedimentary units such as shales of the Lower Devonian Wood Bay Formation and coals of the uppermost Devonian-Mississippian Billefjorden Group partitioned deformation, resulting in significant contrast in deformation intensity between stratigraphic units.
PLoS One
October 2024
Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada.
Modern-day terrestrial amphibians pale in comparison to their monstrous ancient relatives, the Late Carboniferous and Early Permian trematopid temnospondyls. With a skeleton that clearly indicated a terrestrial mode of life and armed with an impressive set of large, recurved marginal dentition and palatal fangs for holding their prey-this group of terrestrial temnospondyls roamed North America and Central Europe as a top predator. Lack of substantial informative fossil material has previously limited our understanding of trematopid diversity and ontogeny.
View Article and Find Full Text PDFACS Omega
September 2024
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
Industrial quantities of tight gas from the Carboniferous Benxi Formation have been found in the southern Ordos Basin. The source and contributions from mudstone and coal in the Benxi Formation to the tight gas are still unclear, and the hydrocarbon generation potential and kinetics of the Benxi Formation mudstone have rarely been reported, which has halted resource evaluation of tight gas. Confined pyrolysis experiments were performed to determine the yields and kinetic parameters for gaseous hydrocarbon formation for a representative sample of a Benxi Formation mudstone from the Ordos Basin, with a hydrogen index (HI) of 137 mg/g TOC and of 434 °C.
View Article and Find Full Text PDFGeobiology
August 2024
WA Organic and Isotope Geochemistry Centre, The Institute for Geoscience Research, School of Earth & Planetary Sciences, Curtin University, Perth, Western Australia, Australia.
The Rhynie Chert (Lower Devonian, Scotland) hosts a remarkably well-preserved early terrestrial ecosystem. Organisms including plants, fungi, arthropods, and bacteria were rapidly silicified due to inundation by silica-rich hot spring fluids. Exceptional molecular preservation has been noted by many authors, including some of the oldest evidence of lignin in the fossil record.
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