云南中、新生代地质构造演化与蒸发岩建造

本文运用板块构造学说观点,分析讨论了云南中、新生代地质构造演化的特点和过程,阐明蒸发岩建造是本区板块活动发展到一定阶段的成矿作用产物.根据盐系剖面结构、矿物组合、矿石类型、微量元素和重金属含量、稳定同位素组成等对比,认为滇中、滇西两大含盐盆地具有不同的构造演化背景,其蒸发岩矿床受各自盆地成盐期基底构造活动性及后期板块碰撞挤压的不同影响控制.对著名的滇西勐野井钾盐矿床成因,作者认为物质来源与海水的补给有关,但提出并非直接来自海洋,而是经深循环变质为氯化物型卤水后,在新增大陆边缘裂谷盆形成的“高山深盆”陆相环境下蒸发而成.

GEOLOGIC-TECTONIC EVOLUTION AND EVAPORITE FORMATION OF MESOZOIC-CENOZOIC ERA IN YUNNAN

Abstract>In which there are many salins deposits, the red bed basins of Mesozoic-Conozoic era are distributed in the Yunnan province. It is the most important producing area of "rock salt" in. China and has a ionj history of exploitation . Since the sixties, the work of wide scope for prospecting potash has developed, as the results of which, Mengyejing potash deposit and a number of potash-bearing salt deposits have been discovered. Reviewing the achievement of Predecessors,a weak link can be found out. Nearly the relation between tectonics and saiification has not yet been touched upon in their writings, thus a series of peculiar penomena in the region can not be explained satisfactorily. Base on the study of plate tectonics in Yunnan,it is thought by the writer that the evaporitc formation of Meso-Cenozoic era in Yunnan is not an isolated sedimentary event, on the contrary, it is the products of certain deveiopping stage in plate tectonic movement for that region. 1. Features of cvaporite formation. (1)