三、变质岩区的调查研究工作有重要突破中和深变质岩往往是由于各种地质作用经过多次叠加而形成的极其复杂的地质体。在许多情况下,这类岩石经历了超变质作用和花岗岩化作用,其原来面貌发生了极大的变化。这样形成的产物,可能一方面在某种程度上具有一些沉积岩或沉积火山岩(如果原岩是这类岩石的话)的特征,而另一方面在更大程度上具有“岩浆岩”的特征。 Third, the study of metamorphic rock area has an important breakthrough Neutral metamorphic rock is often due to a variety of geological effects after the superposition of the formation of an extremely complex geological body. In many cases, these rocks underwent metamorphism and granitization, their original appearance has undergone great changes. The product thus formed may, on the one hand, be characterized, to some extent, by some sedimentary or sedimentary volcanic rocks (if the original rock was of this type) and, on the other hand, by a greater extent “magmatic rock”.