نتایج جستجو برای: mafic composition
تعداد نتایج: 261231 فیلتر نتایج به سال:
The Goushe granitoid Pluton is located southeast of Boroujerd. The study area is composed of granite, granodiorite and the microgranular enclaves located in it with the granodiorite to quartzmonzodiorite combination. The microgranular enclaves presence along with evidence of the presence of the non-equilibrium textures such as dissolved margin and plagioclase zoning, sieve textures, mafic clots...
Findings of coesite and microdiamond in metamorphic rocks of supracrustal protolith led to the recognition of continental subduction to mantle depths. The crust-mantle interaction is expected to take place during subduction of the continental crust beneath the subcontinental lithospheric mantle wedge. This is recorded by postcollisional mafic igneous rocks in the Dabie-Sulu orogenic belt and it...
Large Ra excesses in a number of mafic arc magmas, and geophysical observations of earthquake hypocenters locations, indicate that mafic melts can get transferred from source to surface within days to ~1 kyr. Decreasing Ra–Th disequilibria with increasing SiO2 in co-magmatic suites of individual arc volcanoes suggest that magma differentiation often occurs on timescales of a few thousand years ...
Major element compositions of glass inclusions in olivine and plagioclase phenocrysts from representative Mariana arc lavas show that mafic Mariana arc liquids are tholeiitic and not high-alumina, implying that the high-alumina characteristic of these lavas reflects accumulation of plagioclase. Glass inclusions also show the common occurrence of felsic melts previously unrecognized among Marian...
the dehno granite massive is located in the east dehno village and southern khomein city and within themetamorphic sanandaj–sirjan zone. the composition of these rocks include: granodiorite, quartzdiorite(tonalite), monzogranite and leucogranite. quartz, alkali feldspar, plagioclase, biotite, andalusite, hornblendemuscovite, tourmaline, zircon and apatite are examples of the existing major and ...
Clementine ultraviolet-visible (UVVIS) data are used to examine the compositions of 18 pyroclastic deposits (15 small, three large) at 13 sites on the Moon. Compositional variations among pyroclastic deposits largely result from differing amounts of new basaltic (or juvenile) matehal and reworked local matehal entrained in their ejecta upon eruption. Characterization of pyroclastic deposit comp...
The Xade Complex is an unexposed Y-shaped body, approximately 100 km long and 25km wide, located close to the western margin of the Kaapvaal craton in Botswana. The Complex is characterized by large coincident magnetic and gravity anomalies. It is completely covered by varying thicknesses of Kalahari sediments as well as by Karoo strata, which means that detailed analysis of high resolution air...
High-pressure polymorphs recovered in terrestrial craters are evidence of meteoroid impact events on the Earth’s surface. Despite countless impact craters on the Moon, high-pressure polymorphs have not been reported to date in returned Apollo samples. On the other hand, recent studies report that the high-pressure polymorphs of silica, coesite and stishovite occur in shocked lunar meteorites. W...
1 Geological carbon capture and storage in mafic and ultramafic rocks – Muscat, 2011
Inclusions of quenched mafic magma occur in a 21 Ma rhyolite lava and precursory non-welded tuff that form the Spor Mountain Formation in west-central Utah. The mafic inclusions are not lithic inclusions; no comparable volcanic unit was present at the surface when the Spor Mountain Formation erupted. Mineral and bulk compositions preclude liquid immiscibility. The mafic inclusions show clear mo...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید