粤西罗定南部变质地层研究的新进展

A NEW RESEARCH PROGRESS ON THE METAMORPHOSED STRATA IN THE SOUTH OF LUODING COUNTY, WESTERN GUANGDONG

对罗定南部时代和划分有争议的一套绿片岩相变质地层进行了研究,大量的野外观察表明,前人所划分的不同时代的地层实际上为同一时代、连续沉积的地层,并发现其含有丰富的微古植物化石,经鉴定其时代为志留纪,通过与邻近地区下志留统岩性、岩相和沉积环境的对比及粤西地区构造历史的综合分析,认为该套地层同属早志留世。

There are not consensus to the time and division of greenschist-facies metamorphosed strata in the south of Luoding county, western Guandong due to no finding fossils. Based on a large amount of field observation, it is determined as a suite of continuous sedimentary strata and formed at the same time. It is found that there are abundant micropaleobotany fossils identified to be Silurian in this strata. By comparison with the sedimentary petrography, facies and environment of lower Silurian series in the adjacent area and analysis of the tectonic evolution history in western Guangdong, it is suggested that the metamorphosed strata be formed during the early Silurian period.