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白垩纪厚壳蛤生物礁在我国还是第一次发现。然而,在国外对厚壳蛤类的形态、生态以及成礁的特点都进行了比较深入的研究,认为在白垩纪的建隆(buildup)中,厚壳蛤类有了极大的增加,在碳酸盐的堆积中起了很大的作用,并常常构成了在陆棚环境内的一些生物丘,或者沿陆棚边缘形成礁的格架。而且有的厚壳蛤礁(丘)还是世界一些最大油田的储集岩的重要组成部份。可见其在理论上和实践上的重要意义。岗巴厚壳蛤礁位于西藏岗巴县城,形成时代属晚白垩世。其岩层、造礁的厚壳蛤生物以及礁相带等特征,分别叙述如后。
The Cretaceous thick-shelled clam reef was first discovered in our country. However, the morphological, ecological and reef-forming characteristics of the clam in the world have been studied in depth. It is believed that in the Cretaceous buildup, the clams have been greatly increased in Carbonates play a large part in the accumulation and often form biological mounds within the shelf environment or reef formations along the edge of the shelf. And some thick clams reefs (mounds) or an important part of the reservoir rock of some of the world’s largest oil fields. Shows its theoretical and practical significance. Gap clam reef thick clam reef located in Gamba County, Tibet, the formation of the age of Late Cretaceous. Its rock formations, reef-forming thick-shelled clam creatures, and reef-facies features are described later, respectively.