摘要
从原二朗坪群中解体出来的石界河群主要为一套泥砂质沉积建造。根据矿物世代关系及矿物共生组合,可划分出绿泥石-黑云母带、石榴石带、十字石-红柱石带和红柱石-堇青石带四个变质带,其变质作用属低压相系,变质过程中温压演化趋势和变质作用PTt轨迹综合研究表明石界河群因秦岭群向北逆冲而被掩埋,在深部发生热松弛而升温,之后又因构造隆起和侵蚀,压力明显下降,但温度则继续保持了一段时间。
The Shijiehe group is composed of mica-schist and quartz-schist with metamorphic conglomerate, whose protolith formation is silt sediment. According to the mineral generation and assembrage, four progressive mineral zones are divided. From low to nigh grade, they are termed Ch-bio zone, Gi zone, And-stau zone and And-cord zone. Mineral assembrage and P-T conditioms indicate a low pressure metamorphic series. The tendency of the P-T evolution and PTt path suggest that the upper paleozoic Shijiehe group uplift resulted in part form erosion and tectonism.
基金
国家自然科学基金