Lect2-Sequencestrat-Concept

1、Lets begin!层序地层与盆地沉积动力学陈代钊 （博士，研究员）沉积学、层序地层/旋回地层、盆地分析、沉积地球化学和古海洋学Dzh-http:/Contents Historical review and perspective Sequence Stratigraphy: concepts and definitions Marine Sequence Stratigraphy Nonamrine Sequence Stratigraphy Carbonate Sequence Stratigraphy Methodologies for sequence stratigraphy s

2、tudies (seismic, well log, core and outcrop data) Sea Level Change层序地层基本概念和原理 I.导论 （盆地形成过程、盆地边缘） II.相对海平面变化、构造和全球海平面变化(Relative sea-level, tectonics and eustasy) III.沉积物供给 (Sediment supply) IV.层序地层术语和概念 (Terminology and concept of sequence stratigraphy) V.高分辨率层序地层和准层序-旋回地层 (HR sequence stratigraphy

3、& parasequences)-cyclostratigraphy VI.实例简介I: 导论 1.1 盆地形成伸展盆地（Extensional Basin) 前裂谷阶段（Prerift phases)-大层序（Megasequences) 同裂谷阶段（Synrift phases-Megasequences)-活动断层控制 后裂谷阶段（Postrift phases-Megasequences)-海平面变化起主导作用挤压（前陆）盆地（Compressional or Foreland Basin) 由岩石圈加载于冲断带之上形成 特征的向冲断带前沿加厚的楔壮充填物-前陆盆地大层序走滑盆

4、地（Strike-slip Basin） 没有特征的沉降样式 1.2 盆地边缘盆地边缘沉积几何形态 顶积层（Topsets)-盆缘近端沉积体（10) 底积层（Bottomsets) 退超坡折(Offlap break) vs. 沉积滨线坡折（Depositional shelf break)ClinoformsOfflap breakSea-levelCoastal onlap(or bay line)Typical profile of a prograding basin-margin unit, comprising topsets and clinoforms separated by

5、 a break in slope; the offlapbreak. Bottomsets may also be present. BottomsetsTopsetsonlap Types of Basin-margin Shelf-break margins: typical of PCM, with well developed depo-clinoforms, submarine fan deposits due to mass failure. Ramp margins: Shallow WD, STM & CRT extensive, dip50 Ma), 2nd-ord

6、er (3-50 Ma), 3rd-order (0.5-3 Ma), 4th-order (0.01-0.1 Ma), 5th-order (basin subsidence at offlap brk. Type II: Rate of eustatic fall pelagicturbiditePelagicturbiditePelagicturbidite9Cycle Stacking Patterns and Sequences in the Devonian Carbonates, South ChinaGivetianFrasnianFamennian123456789Problems and pitfalls of high-resolution sequence stratigraphy Identification of prseq, tenuous without core control, good biostrat control or seismic indicators. Prseq correlation not straightforward. SB recog, diffi