Palaeoproterozoic high-K I-type granites, high-level porphyry intrusions, and felsic volcanic rocks of the Whitewater Volcanics dominate the Hooper and Lamboo Complexes in the Kimberley region of northwestern Australia. The granites, porphyries and volcanic rocks are gradational into each other in the field, and they have the same mineralogy, similar major and trace element abundances, and indi...

The mineralogical studies of rare-element (REL) pegmatites are important for unraveling the ore-forming process and evaluating REL mineralization potential. Chinese Altai orogenic belt hosting more than 100,000 pegmatite dykes is famous rare-metal resources worldwide diverse types. In this paper, we present results EMPA LA-ICP-MS muscovite from typical Altai. studied Li-Be-Nb-Ta, Li-Nb-Ta, Nb-T...

Diapirism has been discredited as a transport mechanism for magmas partly because diapirs seem to be unable to bring magmas to shallow crustal levels (< 10 km) and partly because recent developments in the theory of dyke propagation have shown that sufficiently wide dykes are able to efficiently transport felsic magmas through the crust. However, it is still unclear how felsic dykes grow to wid...

Major overturn within a magma chamber can bring together felsic and mafic magmas, prompting de-volatilisation and acting as the driver for Plinian eruptions. Until now identification of mixing has been limited to analysis of lavas or individual crystals ejected during eruptions. We have recovered partially developed cumulate material ('live' cumulate mush) from pyroclastic deposits of major eru...

105 Abstract: Origin of A-type alkali feldspar granites is currently the subject of a world-wide debate. Contrasting hypotheses have been proposed, which range from an entirely crustal origin to an almost complete mantle derivation. A-type alkali feldspar granites belong to either unimodal granite (rhyolite)-dominated association, or bimodal gabbro (basalt)-granite (rhyolite) suite. It is argue...

The Wadhrai granite stock is a part of the Nagar Parkar Igneous Complex, an extension Neoproterozoic Malani Suite western Rajasthan. It occupied by petrographically uniform comprising perthite, plagioclase, quartz, with small quantities biotite, opaque oxides, titanite, and secondary minerals. rocks are sparingly porphyritic contain dykes microgranite, aplite, rare pegmatite. In south-central p...

[1] Stacking of approximately 1500 radial receiver functions recorded at about 80 broadband seismic stations deployed in southern Africa reveals systematic spatial variations in the ratio of crustal P and S wave velocities (F), crustal thickness (H), and the amplitude of the converted Moho phases (R). The eastern Zimbabwe and the southern Kaapvaal cratons are characterized by small H ( 38 km), ...

West Rota Volcano (WRV) is a recently discovered extinct submarine volcano in the southern Mariana Arc. It is large (25 km diameter base), shallow (up to 300 m below sealevel), and contains a large caldera (6 ¥ 10 km, with up to 1 km relief). The WRV lies near the northern termination of a major NNE-trending normal fault. This and a second, parallel fault just west of the volcano separate uplif...

New geochemical data including Sm/Nd isotopic data show evidence for an early Paleozoic arc/back-arc complex in the Nashoba terrane of southeastern New England. The Nashoba terrane lies between rocks of Ganderian affinity to the northwest and Avalonian affinity to the southeast. It consists of early Paleozoic mafic to felsic metavolcanic and metasedimentary rocks that were intruded by intermedi...