Results 81 to 90 of about 2,124,047 (278)

Detrital zircon SHRIMP U-Pb age study of the Cordillera Darwin Metamorphic Complex of Tierra del Fuego : sedimentary sources and implications for the evolution of the Pacific margin of Gondwana [PDF]

, 2010
The Cordillera Darwin Metamorphic Complex in the southernmost Andes includes a basement of probable Palaeozoic age, a mid-Jurassic and younger volcano-sedimentary cover, and a suite of Jurassic granites, all of which were jointly metamorphosed during the
Calderon, M., Fanning, C.M., Herve, F., Klepeis, K., Mpodozis, C., Pankhurst, R.J., Thomson, S.N.   +6 more
core   +1 more source

Devonian Sandstone Lithostratigraphy, Northern Arkansas [PDF]

, 1977
Two areas of Devonian sandstone development may be recognized in northern Arkansas. In northwestern Arkansas, the Clifty Formation comprises a massively bedded, super mature quartz arenite of Middle Devonian age overlain by thinner bedded, phosphatic ...
Hall, Jeffery D., Manger, Walter L.
core   +2 more sources

A Cenozoic-style scenario for the end-Ordovician glaciation [PDF]

, 2014
The end-Ordovician was an enigmatic interval in the Phanerozoic, known for massive glaciation potentially at elevated CO2 levels, biogeochemical cycle disruptions recorded as large isotope anomalies and a devastating extinction event.
Achab, A, Asselin, E, Dabard, MP, Desrochers, A, Farley, C, Ghienne, JF, LOI, ALFREDO, Paris, F, Vandenbroucke, TRA, Veizer, J., Wickson, S   +10 more
core   +8 more sources

Stratified Pit Features at the Presbytère de l'Ancienne‐Lorette (CeEu‐11) and the Fort Odanak (CaFe‐7) Sites in Québec, Canada: A Comparative Geoarchaeological Analysis

Geoarchaeology, Volume 41, Issue 3, May/June 2026.
ABSTRACT A geoarcheological study of two large, stratified Indigenous pit features discovered at two Jesuit mission sites in Québec (Canada) was carried out to offer a detailed documentation of their contents and better understand their use over time. One of the pits is a 17th c.
Sarah Robert, Allison Bain, Najat Bhiry
wiley   +1 more source

Effect of the hydrothermal activity in the Lower Yangtze region on marine shale gas enrichment: A case study of Lower Cambrian and Upper Ordovician-Lower Silurian shales in Jiangye-1 well

Open Geosciences, 2018
Finding favorable sites for the exploration of shale gas, is still one of the important areas of research that needs immediate attention. The content of organic matter in shale plays a crucial role in the hydrocarbon generation potential, reservoir space
Liu Weiwei, Zhang Kun, Jiang Zhenxue, Jiang Shu, Song Yan, Jia Chengzao, Huang Yizhou, Wen Ming, Liu Tianlin, Xie Xuelian, Wang Pengfei, Shan Chang’an, Liu Xiaoxue, Wang Xin   +13 more
doaj   +1 more source

On the Upper Ordovician unconformity in the Pyrenees

, 2007
In recent years, contradictory reports about whether or not an unconformity exists at the base of the Upper Ordovician succession of the Pyrenees have been made. In the Cerdanya area (Central Pyrenees), good outcrop evidence for this unconformity is displayed at the base of the Rabassa conglomerates.
Casas Tuset, Josep Maria, Fernández, Óscar   +1 more
openaire   +2 more sources

The first report of South American edrioasteroids and the paleoecology and ontogeny of rhenopyrgid echinoderms [PDF]

, 2013
A new species of rhenopyrgid edrioasteroid Rhenopyrgus piojoensis sp. nov. is described form the Silurian (Lower Lud− low) Los Espejos Formation in the Precordillera of Argentina.
Heredia, Susana Emma, Mestre García, Ana Isabel, Rodríguez, Cecilia María, Sumrall, Colin D.   +3 more
core   +1 more source

Origins of the Pangkaimen Au Deposit in the Northern Great Xing'an Range, China: Evidence From Geochronological, Geochemical, Fluid Inclusion, and H–O–S–Pb Isotope Data

Geological Journal, Volume 61, Issue 5, Page 1291-1309, May 2026.
The Pangkaimen Au–Ag deposits belong to the epithermal Au deposits, which are of great significance for guiding the research and development of this type of gold deposit. Metallogenic model diagram of Pangkaimen Au–Ag deposit. ABSTRACT The gold (Au) metallogenic belt in the northern Great Xing'an Range is characterised by the wide occurrence of the ...
Sheng Lu, Hongpeng Chen, Chenglu Li, Ye Wang, Tiesheng Li, Rigen Wu, Zengtao Li, Zhichao Song, Xiannan Zhu   +8 more
wiley   +1 more source

Thermodynamic Constraints on H2 Production and Habitability From Mg‐Rich Serpentinites as Mars Analogs

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract Serpentinization produces hydrogen and methane through abiotic water‐rock interactions, potentially supporting chemotrophic life in planetary subsurface environments. Serpentine deposits in the Martian Noachian landscapes of Nili Fossae and the Southern Highlands have been considered as potential paleo‐habitable zones. However, the geochemical
Devan M. Nisson, Mohit Melwani Daswani, Emmy B. Hughes, Scott M. Perl, Varsha M. Nair, H. M. T. G. A. Pitawala, Sanjeewa P. K. Malaviarachchi, P. L. Dharmapriya, Meththika Vithanage, Amit Basu Sarbadhikai, Francis Rivera‐Hernández, Suniti Karunatillake   +11 more
wiley   +1 more source

Reconstruction of karst aquifer system beneath lower coal group and source-specific prevention and control technology for karst water disaster in Huainan Coalfield

Meitan kexue jishu
The Huainan Coalfield boasts abundant coal resources, with an annual coal production of 80 million tons in 2022, making it one of China's major coal-producing regions in eastern China.
Zhigang XIE, Feng HAN, Shancheng CHEN, Hai DING, Gui SUN, Guangquan XU   +5 more
doaj   +1 more source