三叠纪扬子板块的漂移导致下扬子区石膏、硬石膏矿床的形成  

Formation of Gypsum and Anhydrite in Lower Yangtze Valley by the Drifting of Triassic Yangtze Plate

作　　者：钱迈平[1] 厉建华[2] 孙万铨[1] 

机构地区：[1]南京地质矿产研究所,江苏南京210016 [2]江苏省地质调查研究院徐州分院,江苏徐州221004

出　　处：《江苏地质》2002年第3期129-134,共6页Jiangsu Geology

基　　金：中国地质调查局综合研究项目 (2 0 0 113 0 0 0 0 5 3和2 0 0 113 90 0 0 0 72 )成果

摘　　要：下扬子区中—下三叠统广泛分布一套厚几十至数百米的石膏、硬石膏矿层 ,具较大的经济价值。笔者经多年野外工作 ,在掌握大量第一手资料的基础上 ,研究发现 :由于扬子板块在三叠纪期间从赤道附近的暖湿气候带向北回归线附近的干热气候带漂移 ,并与亚洲板块碰撞抬升 ,造成其地理环境由热带陆表海向亚热带潮坪—泻湖转变 ,同时导致其生物群、沉积相及地球化学等发生一系列演变 ,是这套石膏。The gypsum and anhydrite deposits with thickness of dozens and hundreds of metres mainly belong to original deposition of middle to lower Trassic Series and are widely distributed in stable beds in Lower Yangtze Valley. The investigation shows that changes of their various kinds are dependent on the horizons of the strata. The sequence in ascending order is as follows:thin beded massive fine grained dolomitic anhydrite--dololaminite anhydrite--nodular and mosaic gypsum anhydrite reflecting in certain extent, the differences in sedimentary environment along with the diversity of stages in the development of the salt lake. According to paleontology, sedimentology and paleogeomagnetism in Low Mid Triassic System in lower Yangtze Valley, it creates much favourable conditions of geography, biogeny, topography and geochemistry for the formation and preservation of gypsum anhydrite deposit when the Yangtze Block moved over from around the equator, an epicontinental sea under a warm moist climate, to surround the tropic of cancer collided with Asean Block, rose and changed into tidal flat lagoon or sabkha under an acid hot climate.

关 键 词：石膏及硬石膏 三叠纪 爆块 漂移 下扬子区 

分 类 号：P534.51[天文地球—古生物学与地层学] P619[天文地球—地质学]