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丹巴地区位于松潘—甘孜造山带中部。区域动热变质作用主要发生于印支晚期—喜马拉雅早期,与深层滑脱-逆冲作用有关。根据特征矿物组合.丹巴地区变质岩可划分出六个变质带:绢云母—绿泥石带、黑云母带、石榴子石带、十字石带、蓝晶石带和夕线石带。石榴子石生长环带代表每段时间矿物晶体边部的平衡,可用于推测石榴子石生长时的P-t轨迹。利用石榴子石—黑云母温度计和石榴子石—斜长石—Al2SiO5-石英压力计得到石榴子石的参考温度、压力,根据环带定量计算得到的变质作用p-t轨迹为顺时外形式,与其所处的构造背景为大陆碰撞造山带是一致的。
Danba area is located in Songpan - Ganzi orogenic belt in the middle. Regional dynamic thermal metamorphism occurred mainly in the late Indosinian - early Himalayan, and deep slippage - thrust effect. According to the characteristic mineral assemblage. Danba area metamorphic rocks can be divided into six metamorphic belt: sericite - chlorite belt, biotite belt, garnet belt, cross belt, kyanite belt and stilts. The garnet growth annulus represents the balance of the mineral crystal edge at each time and can be used to infer the P-t trajectory of garnet growth. The reference temperature and pressure of garnet are obtained by using garnet-biotite thermometer and garnet-plagioclase-Al2SiO5-quartz pressure gauge, and the pt trajectory of metamorphism obtained from quantitative calculation of annulus is clockwise The tectonic setting is consistent with continental collision orogenic belt.