志留纪早期上扬子海域南部桐梓上升的新证据  

NEW EVIDENCES OF EARLY SILURIAN TONGZI UPLIFT FROM SOUTHERN UPPER YANGTZE SEA

作　　者：王怿[1] 戎嘉余[1] 唐鹏[1] 吴荣昌[1] 

机构地区：[1]现代古生物学和地层学国家重点实验室,中国科学院南京地质古生物研究所,江苏南京210008

出　　处：《地层学杂志》2013年第2期129-138,共10页Journal of Stratigraphy

基　　金：国家基础发展规划项目(973项目)(2012CB821901);国家自然科学基金委(41221001;41172013);中国地质调查局项目(12100122332)资助;IGCP 591(早;中古生代重大事件)项目成果之一

摘　　要：对贵州省遵义正安和务川等4条志留系新剖面的野外调查发现,正安石桥沟和务川珍珠桥从石牛栏组顶部到马脚冲组底部连续发育多层泥裂构造,这是志留纪早期桐梓上升的新证据。在黔北地区,桐梓上升发生在石牛栏组顶部到韩家店组(或马脚冲组)底部,延续时间很短,主要分布在贵州省境内,多表现为假整合面(喀斯特侵蚀面)、古风化壳和泥裂构造,为区域古地理再造和古地形恢复提供了依据。桐梓上升使得黔中古陆海岸线北扩,该上升的高度在不同地区不尽相同,南部地区普遍上升较为强烈,多形成高地,北部地区大多上升较弱,多形成较低山丘;它可在部分地区造成地层缺失,也可使地层几乎无明显缺失;它是区域地层划分和对比的标志。桐梓上升是一次区域性抬升运动,主要受控于华南板块内部的块体运移,由来自南方的水平挤压力转变为上、下振荡,造成了川渝黔边区的不均一抬升而后下降。New evidences of Early Silurian Tongzi Uplift have been found at four new sections in the Zheng^an and Wuchuan area in Guizhou Province. Multiple beds with mud cracks are found from the up- permost Shihniulan Formation to the lowermost Hanchiatien （or Majiaochong） Formation at Zheng^an and Wuchuan counties, northern Guizhou. The Tongzi Uplift occurred as several pulses in late Aeronian, mostly expressed as the development of unconformity （including the uneven boundary between the two for- mations above, paleokarst）, weathering crust, and mud cracks. The Tongzi Uplift resulted in the north- ward migration of the shoreline of the Qianzhong Oldland. The magnitude of this uplift varies, with stron- ger uplift in southern areas than in northern areas. The Tongzi Uplift is significant for regional strati- graphic correlation. It is a regional event controlled by tectonic movement of South China. The horizontal process was converted to vertical movement, which led to an uneven uplift in the border regions of Si- chuan, Chongqing and Guizhou provinces.

关 键 词：事件地层学 桐梓上升 志留系 石牛栏组 韩家店组 马脚冲组 贵州 

分 类 号：P534.43[天文地球—古生物学与地层学] P539.6[天文地球—地质学]