Results 81 to 90 of about 63,412 (230)

Confirmation of the impact origin of the Late Ordovician Tvären impact structure (southeast Sweden) and emplacement of impactites in a marine setting

Meteoritics &Planetary Science, EarlyView.
Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska, Sanna Alwmark, Mikael Calner, Sylvain Richoz, Jens Ormö, Erik Sturkell, Carl Alwmark   +6 more
wiley   +1 more source

Petrographic Analysis of Mafic and Ultramafic Rocks in Northern Thailand: Implications for CO₂ Mineralization and Enhanced Rock Weathering Approach

Geosciences
Mafic and ultramafic rocks have become a promising approach for atmospheric carbon dioxide (CO2) reduction, as they are major sources of CO2-reactive minerals, i.e., olivine, pyroxene, plagioclase, and serpentine.
Tadsuda Taksavasu
doaj   +1 more source

Polymict melt‐bearing breccia dikes in the Morokweng impact structure formed by slip‐induced mechanical mixing of pseudotachylite and cataclasite along large‐displacement impact faults

Meteoritics &Planetary Science, EarlyView.
Abstract A core drilled through shocked and faulted Archean granitoid gneisses and dolerites in the eroded peak ring of the 70–80 km diameter Morokweng impact structure intersects multiple centimeter‐ to meter‐wide clastic‐matrix breccias containing a polymict clast population of lithic and mineral clasts and altered, millimeter‐ to centimeter ‐size ...
Roger L. Gibson, S'lindile S. Wela, Leonidas C. Vonopartis, Marco A. G. Andreoli   +3 more
wiley   +1 more source

Bio‐mediated cementation of supratidal beach sediments associated with groundwater springs

Sedimentology, EarlyView.
ABSTRACT The formation of beachrock, sensu stricto, via carbonate precipitation in the intertidal zone is widespread throughout the tropics and subtropics. While cementation of supratidal beach sediments has also been noted in several locations, it has received much less attention.
Thomas William Garner, J. Andrew G. Cooper   +1 more
wiley   +1 more source

Neoproterozoic ultramafic and mafic magmatism in the Eastern Cordillera of the central peruvian Andes: the Tapo Massif [PDF]

, 2010
A highly dismembered assemblage of ultramafic and mafic rocks is exposed in the Eastern Cordillera of the Central Peruvian Andes, extending along a discontinuous NW-SE belt over some 250 km between 12° and 9° S of latitude.
Acosta, Jorge, Castroviejo Bolibar, Ricardo, Pereira, Eurico, Rodrigues, Jose F., Tassinari, Colombo G.   +4 more
core   +2 more sources

Rifting and arc-related early Paleozoic volcanism along the North Gondwana margin: geochemical and geological evidence from Sardinia (Italy) [PDF]

, 2012
Three series of volcanic rocks accumulated during the Cambrian to Silurian in the metasediment-dominated Variscan basement of Sardinia. They provide a record of the changing geodynamic setting of the North Gondwana margin between Upper Cambrian and ...
BUZZI L, FUNEDDA A., GAGGERO L, OGGIANO G   +3 more
core   +1 more source

Climate conditions on the South‐Iberian Palaeomargin during the latest Pliensbachian to early Toarcian: A mineralogical and geochemical study from hemipelagic deposits

Sedimentology, EarlyView.
ABSTRACT The integrated analysis of lithofacies, mineralogy and geochemistry of the hemipelagic marine succession exposed in La Cerradura section (South‐Iberian Palaeomargin) provides new information to characterise the palaeoenvironmental conditions during the latest Pliensbachian to early Toarcian, including the Jenkyns Event.
Chaima Ayadi, Isabel Abad, Elisa Laita, Ali Mokhtar Samet, Matías Reolid   +4 more
wiley   +1 more source

Accretionary Tectonics of the North American Cordillera [PDF]

, 1983
Continental geology stands on the threshold of a change that is likely to be as fundamental as plate-tectonic theory was for marine geology. Ongoing seismic-reflection investigations into the deep crustal structure of North America are verifying that ...
Saleeby, Jason B.
core   +2 more sources

Evolution Model for the Paleoproterozoic Talvivaara Mudstone‐Hosted Ni‐Zn‐Cu‐Co Deposit in Fennoscandia

Terra Nova, EarlyView.
ABSTRACT The Paleoproterozoic Talvivaara mudstone is a very large sulfidic Ni‐Co deposit that records enhanced organic matter accumulation during the global Shunga Event. Here, rock geochemistry and microscale S and Fe isotope composition of in situ pyrrhotites and pyrites are studied in well‐characterised, well‐preserved drill core samples.
Raimo Lahtinen, Jaakko J. Laitala, Joonas J. Virtasalo, Martin J. Whitehouse   +3 more
wiley   +1 more source

Crustal structure beneath the Trondelag Platform and adjacent areas of the Mid-Norwegian margin, as derived from wide-angle seismic and potential field data [PDF]

, 2010
The outer mid-Norwegian margin is characterized by strong breakup magmatism and has been extensively surveyed. The crustal structure of the inner continental shelf, however, is less studied, and its relation to the onshore geology, Caledonian structuring,
Breivik, A. J., Faleide, J. I., Flueh, Ernst R., Mjelde, R., Murai, Y., Raum, T.   +5 more
core