海南岛几个重大基础地质问题的探讨

海南岛有无泥盆纪地层？有无加里东运动？有无加里东期花岗岩？历来是大家关注和争论的焦点问题。在１：５万昌江县幅和邦溪幅地质调查研究中，笔者对上述问题进行了探讨，并取得了一些重要进展：首次在海南岛发现珊瑚化石Ｃｙｓｔｏｐｈｒｅｎｔｉｓ ｋａｌａｏｈｏｅｎｓｉｓ Ｙｕ，结合旋回地层学研究主为，在昌江县鸡心－鸡实一带南好组（Ｃ１ｎ）中下部可能存在中晚泥盆世地层；首次发现并圈定了加里东期花岗岩体，时代为３６

Some Important Fundamental Geological Problems in Hainan Island

There are three key problems in Hainan Island, i. e. Devonian sediments, Caledonian movement and Caledonian granite. In the process of 1: 50, 000 regional geological surveys of the Changjiang Sheet and Bangxi Sheet, some important advances have been made in these problems. (1) According to the first discovery of the coral Cvxtophrentis kalaohoensis Yu and the study of cyclic stratigraphy , it is suggested that the middle and lower parts of the Nanhao Formation might belong to Middle-Late Devonian sediments in the Jixing-Jishi area,Changjiang County. (2)The Caledonian granite has been first outlined in the Baomeiling area .which is 369-410 Ma in age. (3) According to the regional angular unconformity and metamorphic and deformational characteristics, the Caledonian movement has been determined to be an important tectonic event in the crustal evolution of Hainan Island and may be compared with the Late Caledonian movement of South China.