Results 71 to 80 of about 24,905 (235)
The older ultramafic rocks of Aberdeenshire, similarities to SSZ ophiolites and significance for regional tectonics [abstract] [PDF]
It has long been known that there are at least two phases of mafic-ultramafic magmatism in NE Scotland (Read 1919), the well known Younger Gabbro suite and a lesser known ‘Older suite’.
Styles, Michael
core
An outstanding feature of the Mexican Cordilleran magmatic arc between Sonora and Chiapas is the presence of numerous plutonic and batholitic bodies of Cretaceous to Miocene ages.
Daniel Villanueva-Lascurain +5 more
doaj +1 more source
Putative Analogs of Pyrite Suns Forming in Proglacial Alaska Mudflats
Abstract Disc‐shaped pyrite suns of the Pennsylvanian age Anna Shale are thought to have formed where pressure restricted pyrite crystal growth to a flattened disc shape during diagenesis at the Anna Shale and the underlying Herrin coal boundary.
Heather L. Fair +2 more
wiley +1 more source
Mineral chemistry of late Variscan gabbros from central Spain: constraints on crystallisation processes and nature of the parental magmas [PDF]
© 2016. Universidad Complutense de Madrid. The commercial rights of the printed and online versions of Journal of Iberian Geology are property of the Universidad Complutense de Madrid (UCM) and the Consejo Superior de Investigaciones CientÍficas (CSIC),
Jeffries, T +3 more
core +3 more sources
Abstract Granitoid magmatism along the western Pacific margin records interactions between subduction dynamics and crust–mantle processes; however, the links between plate reorganization and magma‐source evolution remain debated. Here we integrate U–Pb zircon geochronology with Pb–Sr–Nd–Hf isotope systematics to investigate Cretaceous–Paleogene ...
Nghiem V. Dao +7 more
wiley +1 more source
The Geologic Features of the Occurrence of Copper in North America [PDF]
Copper is of such widespread natural occurrence in North America and there are so few metal-mining districts that have not contributed to its production that it is obviously necessary in any brief general treatment of the geology of the copper deposits ...
Ransome, F. L.
core
Mafic and ultramafic plutonic igneous bodies, with small and big outcrops, between Shemshak rock units (Jurassic) are observed in east of Imam Zadeh Hashem, in southern Guilan province.
Mojgan Salavati, Reza Fahim Guilani
doaj
Abstract One promising potential site for extracting supercritical geothermal fluids is the Krafla volcano, Iceland, into which a borehole was drilled very close to a shallow rhyolite magma chamber at about 2 km depth. Besides the technical challenge to drill in this setting, the extreme temperature conditions of T > 900°C close to the magma body may ...
E. Rybacki +3 more
wiley +1 more source
Shock recovery experiments confirm the possibility of transferring viable microorganisms from Mars to Earth [PDF]
Extract from introduction: With regard to the impact and ejection phase we tested the case for the transfer of microorganisms from Mars to Earth. Using a high explosive set-up thin layers of bacterial endospores of Bacillus subtilis, of the lichen ...
Cockell, C. S. +7 more
core
The brittle‐ductile rheological behavior in subduction zones is commonly proposed to explain deep transient slips. Generally observed at large scales in tectonic “mélanges”, here we show that it is also observed at the grain scale in exhumed blueschist ...
A. Maitre +3 more
doaj +1 more source

