徐宿地区上前寒武系地层单元界面的穿时特征与意义  

FEATURES OF DIACHRONOUS BOUNDARIES IN UPPER PRECAMBRIAN SEQUENCE OF XUZHOU AND SUZHOU AREA, SOUTHEASTERN NORTH CHINA PLATFORM

作　　者：刘家润[1] 吴俊奇[1] 潘国强[1] 张庆龙[1] 孔庆友[1] 曾家湖[1] 施贵军[1] 刘道忠[1] 

机构地区：[1]南京大学地球科学系,江苏南京210093

出　　处：《地层学杂志》2001年第1期75-79,共5页Journal of Stratigraphy

基　　金：原地质矿产部 1/5万<房村幅><双沟幅>区域地质调查项目;中国科学院南京地质古生物研究所现代古生物学和地层学开放研究实验室 N

摘　　要：剖面露头特征显示 ,徐宿地区上前寒武系地层单元 (组、段 )界面普遍是穿时面 ,分别涉及贾园组—望山组各组地层。研究结果表明 ,穿层界面的形态、倾向与界面上下的岩石类型、海进海退、深水方向有着明显的相关性 ;人为选择窄相带浅水相沉积作为地层单元分界面的标志以及沉积相带的侧向迁移是造成界面穿层的原因。鉴于地层单元界面普遍穿时 ,建议采用以斜实线的形式来表述研究区上前寒武系地层柱中穿时界面上下两个地层单元的整合接触和部分同期、部分先后异期的时序关系。The stratigraphical unit's boundaries crossing beds are well exposed in the outcrops of the Upper Precambrian sections in the Xuzhou and Suzhou area, southeastern North China Platform. These boundaries, which refer to all of Precambrian units from the Jiayuan Formation to the Shijia Formation in this area, demonstrate that most of boundaries in the Upper Precambrian sequence in this area are diachronous. The results of this study indicate that the forms and trends of diachronous boundaries relate to different sedimention types and sea level changes. Otherwise, diachronous boundaries of the Upper Precambrian sequence in terms of lithostratigraphy in this area might be caused by selecting the sedimentation of shallow water facies as a mark to identify units and crosswise migration of these facies in this area.

关 键 词：徐宿地区 江苏 安徽 上前寒武系 地层界面 穿时特征 

分 类 号：P534.1[天文地球—古生物学与地层学]