巢湖市二叠纪栖霞组生物碎屑的数量及其地质意义  

Quantity of bioclasts in Permian Qixia Formation,Chaohu City and the geological implications

作　　者：卢小龙[1] 孙林华[1] 陈松[1] 

机构地区：[1]宿州学院地理与环境科学系,安徽宿州234000

出　　处：《安徽地质》2010年第4期251-254,272,共5页Geology of Anhui

基　　金：安徽省高校优秀青年人才基金(2010SQRL190);宿州学院博士(教授)基金(2009jb04)资助

摘　　要：通过对巢湖凤凰山东南坡二叠系下二叠统栖霞组进行了系统的剖面测量,底部为梁山段劣质煤线,上部为灰岩夹有薄层碳质泥页岩,顶部为含燧石结核灰岩,生物碎屑含量具有先增加后减小的规律。结合前人对全球栖霞期古气候、古海洋的研究,栖霞期海平面整体上升,在海侵的过程中出现多次海退,沉积环境为泻湖-局限海湾-开阔台地-碳酸盐岩台地。结合燧石结核主要为热液成因的认识,推断二叠纪栖霞组生物碎屑的变化可能与260Ma峨眉山地幔柱前期地质作用有关。Systematic profile surveying indicates that the lower Permian Qiaxia Formation on the southeast slope of the Fenghuang Mt.,Chaohu is composed of the Liangshan Member of poor shedcoal at the bottom,overlain by limestone intercalated with thin-bedded carbonaceous shale,and chert-bearing nodule limestone at the top,in which the content of bioclasts increases first,then declines.Also supported by predecessors＇ study on global climates and oceans in ancient times,the sea level in Qixia period rose as a whole,advance of sea was accompanied by many times of regression,and sedimentary environment was lagoon-confined gulf-open platform-carbonate rock platform.Considering the fact that chert nodule is mainly of hydrothermal origin,we think that the change of bioclasts in Permian Qixia Formation may be connected with geological process prior to 260Ma Emeishan mantle plume.

关 键 词：生物碎屑 燧石结核 栖霞组 沉积环境 巢湖 

分 类 号：P534.46[天文地球—古生物学与地层学]