Exposures of arc crustal sections represent rare opportunities to directly evaluate lower magmatic processes and their link products in the middle upper crust. Within southernmost Sierra Nevada batholith, Bear Valley Intrusive Suite (BVIS) exposes a contemporaneously constructed ~ 30 km thick intrusive suite, thus is ideal for this type examination. Here we present detailed petrography mineral ...

Metamorphism along the southern margin of the Archean Superior Province has been historically attributed to the Penokean orogeny. A narrow corridor of amphibolite facies rocks north of the main suture does record 1.83–1.80 Ga metamorphic monazite U–Th–Pb ages that mark the culmination of arc accretion. However, subsequent widespread amphibolite facies metamorphism and associated magmatism is re...

Determining the timing, magnitude, and location of deformation due to the Indo-Asian collision is widely acknowledged as an important step in understanding how the lithosphere responds during continental collision. A puzzling result of geological investigations of the Lhasa Block over the past 2 decades has been the apparent lack of significant Tertiary deformation there. Perhaps the most impor...

Products of voluminous pyroclastic eruptions with eruptive draw-down of several kilometers provide a snap-shot view of batholith-scale magma chambers, and quench pre-eruptive isotopic fractionations (i.e., temperatures) between minerals. We report analyses of oxygen isotope ratio in individual quartz phenocrysts and concentrates of magnetite, pyroxene, and zircon from individual pumice clasts o...