摘要
严格按照等时性对比原则,选取岩相古地理图的制图单元。以野外实测剖面为基础,做精细沉积微相研究,在东北地区地层露头剖面识别出海相(浅海亚相、半深海亚相)、三角洲相(三角洲前缘:水下分流河道、河口坝,前三角洲)沉积。在露头点测量基础上,以点带线、以线带面,分析古沉积环境。在野外剖面沉积微相精细划分基础上,结合区域地质资料,编制地层厚度图、砂岩厚度图、泥岩厚度图、碳酸盐岩厚度图、砂地比图、泥地比图、岩比图等图件。在定量分析的基础上,结合优势相原理,编制东北地区中二叠世岩相古地理图,该区域主要发育有三角洲相、碳酸盐岩台地相、浅海相。三角洲相主要分布在西部、东北部、东南部;临近的古陆剥蚀区是主要的陆源沉积体系;碳酸盐岩台地相主要分布在研究区西北部、东部;浅海相分布广泛。
The mapping units of lithofacies palaeogeography map were strictly selected in accordance with the principles of isochronous comparison.On the basis of the sections measured in field survey and the detailed study of fine sedimentary microfacies,we have identified the marine facies（shallow marine subfacies,half deep marine subfacies）and delta facies（delta front： underwater distributary channel,estuary dam and the former delta）sedimentation in outcrop profile in northeast China.Based on the outcrop point measurement,from point to line and from line to plane,the paleoenvironments has been analyzed.On the basis of fine division in the field profile microfacies and combined with regional geological data,the maps of stratigraphic thickness,sandstone thickness,mudstone thickness,carbonate rocks thickness,the ratio of sandstone in the formation,the ratio of mudstone in the formation,the percentage of rocks,etc.have been plotted.On the basis of quantitative analysis and combining the principle of advantages of phase,the lithofacies palaeogeography map of Middle Permian in Northeast region was drawn.In this region mainly developed delta facies,carbonate platform facies,neritic-bathyal phase.Delta facies mainly distributed in the west,northeast,and southeast;the ancient land mass nearby is the main source system;the carbonate platform is mainly in the northwest and east of the work area;the neritic-bathyal phase is widely distributed.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2011年第4期41-51,共11页
Earth Science Frontiers
基金
中国石油化工股份有限公司"中国东北地区油气勘探新领域地质背景研究"项目(YPH08040)
关键词
晚古生代
沉积相
岩相古地理
东北地区
Late Paleozoic
sedimentary facies
lithofacies paleogeography
northeast region of China
