Geological and petrological studies indicate that three phases of metabasic dykes are present in theTaipingzhai-Jinchangyu area within the high-grade metamorphic terrane of eastern Hebei. Garnet andhornblende in metabasic dykes of the second and third phases occur separately, forming two mineral aggregateareas gl+cpx+pl±hy and hb+cpx+pl-hy. PH2O in the rocks appears to be the main factor controlling theformation of the two aggregate areas. Both were formed simultaneously at the same metamorphic temperature. The second-phase basic dykes underwent metamorphism of pyroxene-granulite facies at a temperature ofsome 825C: later the dykes, together with the third-phase basic dykes experienced metamorphism ofamphibole-granulite facies at a temperature of about 750C under pressure of 0.9GPa.
展开▼
机译:地质和岩石学研究表明,在河北东部高档变质地区的Thetaipingzhai-Jinchangyu地区存在三个阶段的达克斯。在第二阶段和第三阶段的新型染料中的石榴石和霍恩在第二阶段进行分别发生,形成两个矿物聚合性GL + CPX + PL±HY和HB + CPX + PL-HY。岩石中的p h 2 sub> o sub>似乎是控制两个聚合区域的形式的主要因素。两者在相同的变质温度下同时形成。第二阶段基础堤坝在825℃的温度下接受辉石颗粒状物相变质:后来染料,与第三期碱基染料在0.9gPa压力下,在约750℃的温度下经历了多晶硅粒子相的变质。
展开▼