安徽宁国胡乐地区奥陶系层序地层学初探  

PRELIMINARY STUDY OF THE ORDOVICIAN SEQUENCE STRATIGRAPHY IN THE HULE AREA OF NINGGUO,ANHUI

作　　者：宫维莉 毕治国[2] 姜立富[3] 齐敦伦[2] 

机构地区：[1]安徽古生物化石博物馆,安徽合肥230001 [2]安徽省地质勘探局327地质队,安徽合肥230011 [3]安徽省地质调查院,安徽合肥230001

出　　处：《地层学杂志》2010年第3期321-327,共7页Journal of Stratigraphy

基　　金：安徽省"宁国市胡乐奥陶纪地层剖面及古生物化石遗迹调查与保护"项目成果

摘　　要：宁国市胡乐镇鸿门—将军岭段新开公路旁奥陶系宁国组出露完好,通过对该段地层进行连续观察和分析研究,发现存在Ⅱ型不整合面、海侵面、最大海泛面等重要的地层界面,以及鲍玛序列、复理石建造等典型的沉积特征。根据海平面变化、地壳沉降和沉积物补给关系,采用基本层序调查方法,将该区奥陶纪地层层序划分为A、B、C、D、E5个层序。其中只有2个(C、E)为完整层序,其余3个(A、B、D)为不完整层序。研究表明,该地区奥陶系为深水盆地沉积,纵向岩性变化小,多数缺失低水位沉积,反映当时海平面升降变化幅度较小,但节奏性的韵律变化仍较明显。The Ordovician strata along the provincial highway 323 and near the town Hule are well exposed. There are sedimentary characters induding,Bouma sequences and flysch sedimentation.We also identified type Ⅱ sequence boundaries,transgressive surfaces,and maximum flood surfaces. The Ordovician strata are divided into five third-order sequences （sequence A,B,C,D,E）,that reflect sea level change,subsidence,and sediment supply.Both sequence C and E are complete sequences. The sequences A,B and D are incomplete. The Ordovician strata represent sedimentation in deepwater basin and with limited lithologic variation vertically. The lowstand system tract is not typically preserved. These features reflect small-scale sea level oscillation.

关 键 词：层序地层 奥陶系 胡乐地区 宁国 安徽 

分 类 号：P539.2[天文地球—古生物学与地层学] P534.42[天文地球—地质学]