Merguerian, Charles, 1985c, Tectonic significance of mylonitic Paleozoic gneissic granitoids in the Shoo Fly Complex, Tuolumne County, California
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چکیده
Paleozoic gneissic granitoids are an important lithologic component of the Shoo Fly Complex of the central Sierra Nevada, California. Field relations, petrographic, and geochemical studies indicate that the gneisses were originally intruded as a seri.es of plutons ranging from gabbro (oldest) to granite and granodiorite (median age) to syenite (youngest) with the granitoid types predominating. Compositionally they express a calc-alkalic to alkalic rock suite. The plutons and related smaller injections truncate an early S1 metamorphic foliation in the Shoo Fly and were isoclinally folded and foliated under peak epidote-amphibolite grade conditions during regional D2 and D3 events.
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