【摘要】 <正> 马角坝位于龙门山褶皱带中段东南侧或华夏龙门山隆起东南边缘。古生代地层以海相碳酸盐岩为主,中生代以碎屑岩为主。陈家崖在马角坝西北侧,主要出露中泥盆统观雾山组和上泥盆统沙窝子组,岩性以白云岩和含白云质灰岩为主。1982年7月笔者首次在陈家崖上发现生物礁及生物层。接着以我院79131班学生为更多还原

【Abstract】 Seven patch reefs of middle-upper devonian have been discovered recently in chenjiaya, Majiaoba, West-Sichuan.The reef-building organisms are stromatopora,tabulata,and tetracoralla with various ecologic types as well. The reef-rocks are mainly bio-bafflestones, and secondly bio-framestones.Several now views concerning these reefs are as follows:1.The patch reefs grew in warm shallow-water carbonate-platform of epicontinental sea in which wind and wave weak. The sequence of biostrome-lentieular patch reef-dome-like patch reef might have formed with the decrease of wind and wave.2.The patch reefs grew continuouslly upward until they came close to sea surface.At the same time, as the sea water became fresher and fresher, the patch reefs finally died. Hence regressive reefs resulted.3.The bio-framestones occured behind the reef core and extended beyond reef. Therefore the place of the reef core varied during the evolution of the reef. The direction of regression may be determinated according to the direction of variation of the reef core.更多还原