秦岭东段陕西旬阳三里峡生物礁是一个发育较好的近南北向展布的石炭纪堤礁．该生物礁的造礁功能比较复杂，在礁的不同生长阶段有不同的造礁作用方式．礁体内生物相对单调，主要为有孔虫、藻类、腕足类及介形类等，它们组成Ｄａｓｙｃｌａｄａｃｅａｅ－Ｃｙｎｏｐｈｙｔａ群落及Ｆｏｒａｍｉｎｉｆｅｒａ－Ｃｙａｎｏｐｈｙｔａ群落．在礁的形成过程中有４个方向的演化序列，它们构成礁形成过程的三个阶段（生物定殖、障积式造礁及包粘式造礁阶段）的主要内容 The Sanli Xia reef in Xunyang, Shaanxi Province in the eastern part of Qinling Mountains is a well-developed Carboniferous Dyke reef with a nearly north-south distribution. The reef reef building function is more complex, in the different growth stages of the reef have different ways of reef. Reef organisms are relatively monotonous, mainly foraminifera, algae, brachiopods and ostracods, which constitute the Dasycladaceae-Cynophyta community and Foraminifera-Cyanophyta community. There are four directions of evolutionary sequence in the formation of the reef, which constitute the main contents of the three stages of reef formation (biological colonization, barrier reef reef formation and package reef formation)