WebJun 1, 2024 · Two–stage Hf model ages suggest that the age of the protolith of the TTG gneisses was ca. 3.4–2.6 Ga, representing a period of paleocontinent formation in the Mesoarchean. WebMostly homogenous schistose greenstone; in places massive, mottled, and containing conspicuous calcite and epidote. Tuffaceous chlorite schist in upper part in northern Pend Oreille County. ... (Jurassic protolith)) Greenschist of central Whatcom and Skagit Counties. Pre-Upper Jurassic metamorphic rocks of the low-grade zone (Jurassic)

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WebIn such cases, where the protolith is obvious because the texture of the protolith is well preserved, the prefix "META" is simply used in front of the protolith name, e.g., METAGRANITE, METABASALT ... GREENSTONE (Metabasalt) Basalt: PHANERITIC: Medium- to coarse-grained, SCHISTOSE texture: MUSCOVITE BIOTITE CHLORITE … WebProtolith can be any type of rock and sometimes the changes in texture and mineralogy are so dramatic that is difficult to distinguish what the protolith was. ... protolith, (g) … cynthia brincat email

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WebThe Acasta Gneiss is a tonalite gneiss in the Slave craton in the Northwest Territories, Canada.The rock body is exposed on an island about 300 kilometres north of Yellowknife.The rock of the outcrop was … WebGreenstone belts get their very name from this prominent rock, which served as protolith for the low-grade metamorphic rock called greenstone. Then, as now, basalt erupted as … WebSee Page 1. 11-The most common type in upper crust a) sedimentary rock b) metamorphic rock c) igneous rock. 12-Basalt metamorphoses to be a) amphibolite b) quartzite c) marble d) schist. 13-If granite has been changed into metamorphic rock it will be a) gneiss b) rhyolite c) greenstone d)slate. 14-some volcanic rocks metamorphose to a) schist b ... billy reed\u0027s restaurant palm springs ca