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麻扎地区弧火成岩是1∶25万麻扎幅区域地质调查过程中发现并厘定的,位于麻扎构造混杂岩带之中,包含着古洋壳消减过程中的一些重要信息。弧火成岩主要由中酸性侵入岩和火山岩组成,具岛弧性质的岩石组合和岩石地球化学特征。对弧火成岩中的角闪石英闪长岩进行锆石SHRIMPU-Pb测年,结果为338Ma±10Ma,时代为早石炭世。麻扎地区弧火成岩的发现,不但证明了在晚古生代出现过麻扎-康西瓦洋(古特提斯),而且说明该洋在石炭纪已经开始俯冲-消减。
The argillaceous rocks in the Mazar area were discovered and determined in the geological survey of 1: 25000 hempzones. They are located in the Mazar tectonic mélange zone and contain some important information in the process of paleoclimate reduction. Arc igneous rocks are mainly composed of medium-acidic intrusive rocks and volcanic rocks, with rock assemblages and petrochemical features of island arc. The zircon SHRIMPU-Pb dating of hornblende diorite in arc igneous rocks is 338 Ma ± 10 Ma dating from Early Carboniferous. The discovery of arc igneous rocks in the Mazar area not only proved that the Mazar-Kangxiwa Ocean (Gut Tethys) had appeared in the Late Paleozoic, but also that the ocean had begun to subduct-decrease in the Carboniferous.