湖北省秭归兴滩地区,地层出露良好,特征明显,在前人研究的基础上,通过野外剖面实测,运用沉积相分析,结合微相及古生物学研究,对湖北秭归兴滩地区的二叠系进行了岩相及沉积划分,对沉积演化做了初步研究。岩相分析表明,研究区中-上二叠统主要由生物碎屑颗粒灰岩、泥晶灰岩、砂屑灰岩、砾屑灰岩、硅质岩等组成。沉积相分析表明,中-上二叠统主要为碳酸盐斜坡、台地沉积,其次为滨岸和盆地沉积。中二叠世发育两个海进-海退旋回,分别为栖霞期和茅口期,晚二叠世吴家坪期主要为开阔台地沉积,总体为2个半旋回。
The stratigraphy is well outcropped with distinctive features in the Xingtan area,Zigui,Hubei province.On the basis of previous work made in the area,this paper divided Permian lithofacies and deposit and preliminarily studied the sedimentary evolution by using measured cross-sections,sedimentary facies analysis combined with microfacies and paleotology.Lithofacies analysis indicates that mid-upper Permian series in the study area comprises mainly bioclast limestone,micrite,calcrenite,calcirudite,silicolite,etc.Sedimentary facies analysis suggests that the mid-upper Permian consists primarily of carbonate slope and platform deposit,secondarily of shoreland and basinal deposit.The mid-Permian consists of two developed transgression-regression cycles respectively of the Qixia and Maokou times,and the late Permian is characterized by open platform deposit of the Wujiaping time,with 2 and a half cycles as a whole.