Results 91 to 100 of about 23,483 (232)
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
Distinct Hadean Mantle Sources of Felsic and Mafic Terranes Juxtaposed in the Paleoarchean
The short‐lived radionuclide system 146Sm‐142Nd can provide direct information about geological differentiation events in the terrestrial Hadean (>4.0 Ga) mantle.
Arathy Ravindran +5 more
doaj +1 more source
The Moho as a magnetic boundary [PDF]
Magnetic data are presented for mantle derived rocks: peridtites from St. Pauls rocks, dunite xenoliths from the kaupulehu flow in Hawaii, as well as peridolite, dunite and eclogite xenoliths from Roberts Victor, Dutoitspan, Kilbourne Hole, and San ...
Mayhew, M. A. +2 more
core +1 more source
Abstract Peridotites record the compositional evolution of the lithospheric and asthenospheric mantle across plume‐related lithospheres, convergent margins, and rift‐related volcanic environments; however, their tectonomagmatic affinities are commonly difficult to resolve using traditional low‐dimensional geochemical discrimination diagrams.
Swarnendu Roy, Koushik Sen
wiley +1 more source
Mineralised ultramafic rocks in South Greenland
In 1960 several mineralised ultramafic boulders with a remarkable content of Pt were found by M. Loretan in the neighbourhood of Sarqa fjord in the Nanortalik district, South Greenland. This stimulated interest in a closer examination of the mafic and ultramafic rocks of South Greenland and in 1962 and 1963 J. P.
openaire +2 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
Olivine Microstructure Constraints on Ureilite Parent Body Deformation
Abstract Ureilites are ultramafic achondrites for which the parent body is unknown. Monomict ureilites, consisting primarily of olivine and pyroxene, are thought to represent mantle residues, carrying essential information for their parent body deformation history.
Yaozhu Li +4 more
wiley +1 more source
Workshop on Magmatic Processes of Early Planetary Crusts: Magma Oceans and Stratiform Layered Intrusions [PDF]
The significance of the lunar highland pristine cumulate samples were reevaluated with the aid of the additional insights provided by geologically constrained terrestrial investigations.
Mccallum, I. S., Walker, D.
core +1 more source
ABSTRACT This study investigates garnet–clinopyroxene double‐layered coronae in a metagabbronorite from the high‐grade metamorphic Gföhl Unit (Bohemian Massif). The coronae formed at the interfaces between relic magmatic orthopyroxene, still preserved in the cores of the coronae, and the plagioclase‐rich rock matrix.
Rene Asenbaum +5 more
wiley +1 more source
Platinum-group element mineralisation in the Unst ophiolite, Shetland [PDF]
The ophiolitic basic and ultrabasic rocks of the island of Unst, Shetland comprise a sequence of harzburgites, dunites, clinopyroxene-rich cumulates, and gabbro, within tectonic blocks that have been thrust over a migmatite complex during the Laxer ...
Gunn, A.G., Leake, R.C., Styles, M.T.
core

