自生矿物是在沉积物沉积以后,完全成岩以前产生的矿物,即在沉积环境之中,沉积物未完全硬化的成岩期间产生的。在这样一个漫长的成岩过程中发生了各种物理化学变化,自生矿物的形成只是其中的一种表现。这个阶段叫做成岩作用阶段。在这个阶段,自生矿物和沉积物都可能发生巨大的变化。由于地球表面70％以上被地球表生作用产生的沉积岩和沉积物所复盖,因此我们应当重视这方面的研究。 在成岩作用研究中的一个重要问题,即成岩作用和变质作用的分界问题,至今还没有取得一致的看法。一般认为成岩作用是在不太深和不太高的温度范围内 Authigenic minerals are minerals that were produced before complete diagenesis after sediment deposition, ie, during diagenesis where sediments were not fully hardened in sedimentary environments. In such a long process of diagenesis, various physical and chemical changes took place. The formation of authigenic minerals is only one of them. This stage is called the stage of diagenesis. At this stage, significant changes in authigenic minerals and sediments may occur. Since more than 70% of the Earth’s surface is covered by sedimentary rocks and sediments produced by epigenetic activities of the earth, we should pay attention to this research. An important problem in the study of diagenesis, that is, the demarcation between diagenesis and metamorphism, has not yet reached a consensus. Diagenesis is generally considered to be in the less deep and not too high temperature range