恒山地区部分熔融地质体填图方法的尝试

An attempt at the mapping method of geological bodies derived from partial melting in the hengshan area

五台群地层呈东西向分布在恒山东段中部，其北为高角闪岩相的恒山片麻杂岩，两者岩性呈渐变过渡关系，由此萌发出片麻杂岩是五台群地层部分熔融而来的思路。经过填图实践，总结出地层与片麻岩体之间存在着仍属地层范畴的片麻岩层这一无序岩石地层单位，并建立起它的填图标志。与地层呈渐变关系的片麻岩体外貌复杂、边界不清，不同于具有一定侵入关系、边界明显、成分均一的片麻岩体，据此划分了原地片麻岩体与异地片麻岩体两个系列。

The Wutai Group is distributed in an east west direction in the central part of the eastern segment of Hengshan Mountain and the high amphibolite facies Hengshan gneissic complex occurs to the north, both showing gradational relationships; from that the authors get the idea that the gneissic complex was derived from partial melting of the Wutai Group. Through mapping, the authors propose that between the Wutai Group and Hengshan gneissic complex there exists a gneiss layer which still belongs to strata and its mapping indicator is set up. The gneiss body which displays gradational relationships with the strata has a complex appearance and indistinct boundaries, being different from the gneiss body which shows a definite intrusive relationship with the strata and has distinct boundaries and an homogeneous composition. On that basis, the autochthonous gneiss and allochthonous gneiss are distinguished.