Introduction: The North Qilian orogenic belt, as the Northern branch of original Tethys tectonic domain, is important for reconstructing evolution ancient Tethys. However, history belt remains controversial. This study addresses this issue from a geochemical perspective. Methods: In study, comprehensive analysis geochronology, whole-rock geochemistry, clinopyroxene mineral zircon Ti crystalliza...

the kasian volcanic body is located in the eastern margin of the zagros thrust belt, close to the sanandaj-sirjan metamorphic zone. these volcanic rocks are mainly composed of andesite and andesite-basalt rocks with porphyritic, hypocrystalline porphyritic, hyalo-porphyritic and hyalo-microlitic porphyritic textures. analyses of the distributions of major, rare earth and trace elements reveal a...

Abstract The Dinner Creek Tuff is an important unit of mid-Miocene rhyolite volcanism contemporaneous to flood basalts the Columbia River magmatic province. Field mapping along with analytical data tuff samples identify two calderas, Castle Rock and Ironside Mountain as venting sites widespread ignimbrites Tuff. Both calderas lie within area proposed general storage main-phase Basalt magmas. ca...

We apply 2-D wave-equation prestack depth migration to a North Sea basalt dataset. High velocity and impedance contrasts across a basalt layer causes low P-wave reflection signal-to-noise ratio under the basalt. We first migrate the P-wave data with a provided depth velocity model, and then replace sub-basalt P-wave velocity with a simple estimate of shear wave velocity and migrate locally-conv...

The proposal by Hubbard et al. (1) that "Very High Alumina basalt" ("VHA basalt") may represent an important primary lunar magma type neglects consideration of certain well-characterized high-magnesium highland rocks, among them spinel troctolite from Luna 20 (2) and Apollo 16 samples (3) and dunite from Apollo 17 samples (4), and the possibility that "VHA basalt" may in fact have originated by...

Abstract The continental crust is strongly depleted in iron relative to mid-oceanic ridge basalt, broadly identical the calc-alkaline magmas, suggesting that differentiation key continent formation. However, it remains contentious as what drives Fe depletion during magmatic crust. two competing hypotheses for differentiation—magnetite versus garnet (± amphibole) fractionation—predict contrastin...

The Columbia River Basalt Group in the northwestern United States, comprising about 230,000 cubic kilometres of rock, exhibits unusual patterns in lava distribution, geochemistry and its apparent relationship to regional tectonics. Consequently, there is little consensus on the origin of its magmas. Here, we examine the isotopic ratios of Sr, Nd, Pb and Os and traceelement abundances in Columbi...

The paper presents two experimental methods for basalt processing by microwaves, and their results. One method employs a single-mode cavity to melt basalt, and to produce a volcanic glass (obsidian). The other method uses an open-end applicator (i.e. a microwave drill [1]) to form holes in basalt rocks. Experimental observations of the basalt interactions with microwaves in these two schemes ar...

Ferroan anorthosite VHK basalt Oldest basalt APOLLO 14 OLDEST MARE BASALT REVISITED: POSSIBLE PETROGENETIC CONNECTION BETWEEN MG GABBRONORITE AND VHK BASALT. T. Arai, H. Takeda, M. Miyamoto, and H. Kojima, Antarctic Meteorite Research Center, National Institute of Polar Research, 1-9-10 Kaga Itabashi Tokyo 173-8515, Japan, [email protected], Research Institute, Chiba Institute of Technology, Ts...