由于地壳运动的多旋回性,势必产生对岩石的多次变质作用现象。不同性质的变质作用的迭加,一般对先期岩石改造作用是不均匀的,也就是说,变中必有不变之处,必保留原来的岩石结构构造的残余。第一次迭加现象也就是第二次迭加作用的残余。一般来讲,迭加和残余是两种不同性质的变质作用类型产物,其现象在岩石上表现特征是不同的。据这一准则,近年来我们对本区以区域变质作用为主体、为背景的多次变质作用进行了逐级依次的恢复。经研究珍珠门组含矿碳酸盐建造,经受了三次大的变质作用的 Due to the multi-cycle crustal movement, it is bound to produce a number of metamorphic rock phenomenon. The superimposition of metamorphism of different nature generally is not uniform to the transformation of the antecedent rocks, that is to say, there must be invariable place in the alteration, and the remnants of the original rock structure will be preserved. The first superposition phenomenon is the remnants of the second superposition. In general, superposition and residual are two different types of metamorphic types of products, the phenomenon of rock performance characteristics are different. According to this guideline, in recent years, we have carried out a series of stepwise restoration of the metamorphism of the background on the basis of regional metamorphism. After the study of pearl gate group bearing carbonate construction, has undergone three major metamorphism