摘要：

Granitoids as categorized by tectonic environment are 1) island arc granitoids (IAG), 2) continental arc granitoids (CAG), 3) continental collision granitoids (CCG), 4) post-orogenic granitoids (POG), 5) rift-related granitoids (RRG), 5) rift-related granitoids (RRG), 6) continental epeirogenic uplift granitoids (CEUG), and 7) oceanic plagiogranites (OP). Of these, the IAG, CAG, CCG, and POG are considered orogenic granitoids, and the RRG, CEUG, and OP are considered anorogenic granitoids. The discrimination of granitoids is based on the major-element chemistry. Various discrimination plots are presented which sequentially discriminate the different tectonic environments. The proposed discrimination scheme is applied to the Proterozoic granitoids of the midcontinent of the United States. It is shown that the Arbuckle granitoids are not anorogenic as previously thought. -from Authors

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