摘要
尽管前人对塔里木盆地塔北地区三叠系进行过沉积与层序地层研究,但是有关全盆范围内层序地层格架研究比较少见。应用现代沉积学和层序地层学的原理和方法,着眼于塔里木盆地台盆区的整体研究,综合利用地震、钻井、测井及分析化验等资料,对研究区三叠系三级层序界面和体系域界面进行识别,共识别出5个具有等时意义的层序界面,对应划分为4个三级层序。结合层序内幕结构划分,建立了台盆区井震统一的层序地层格架。受盆地构造活动等因素影响,各层序横向分布和内部构成各有特点:SQ1和SQ2层序逐渐超覆在塔北隆起南部的斜坡上,而SQ4层序在塔中地区遭受大范围抬升剥蚀,盆地内部各层序分布较稳定。辫状河三角洲和湖泊相是研究区主要的沉积相类型,代表了宽浅型大型坳陷湖盆沉积过程。辫状河三角洲多分布在塔北和塔中的斜坡部位,湖泊相沉积多分布在台盆区中西部,相应发育了辫状分流河道、水下分流河道、河口坝、滨岸沙坝4中主要有利储集砂体类型。通过层序界面的识别与格架的建立,提高了储集层预测的准确性,并为塔里木盆地三叠系整体油气勘探部署提供了依据。
Although predecessors have researched the sedimentation and sequence stratigraphy of Tabei area,the basin wide sequence stratigraphy is considered little.Using the theories and methods of sequence stratigraphy and modern sedimentology,emphasizing the overall research of the whole basin,we analyzed seismic data,logging and drilling core data of Triassic in Tarim Basin and identified the boundaries of sequences and system tracts.And five sequence boundaries with isochronous are developed and four third-order sequences are divided.According to division of internal structure,a unified sequence stratigraphic framework between well and seismic is established in platform area.Affected by tectonic activity and other factors,the characteristics of lateral distribution and internal structure in each sequence are different.SQ1 and SQ2 gradually overlap to the southern slope of Tabei uplift,SQ4 is suffered extensive uplift and erosion in Tazhong area,the distribution of each sequence is more stable in the inner basin.Braided delta and lake is the main sedimentary facies,which represents the deposition of broad-shallow depression lake basin.As the main sedimentation type,braided delta is located in the slope area of Tazhong and Tabei,lake is deposited in the central basin.The favorable reservoir sand is formed by braided channel,underwater distributary channel,channel mouth bar and longshore bar.The identification of sequence boundaries and stratigraphic framework will improve the accuracy of reservoir prediction and provide foundation for integral deployment of petroleum exploration.
出处
《沉积学报》
CAS
CSCD
北大核心
2011年第5期917-925,共9页
Acta Sedimentologica Sinica
基金
中国石油化工股份公司西北油田分公司攻关课题(编号:KY-S-2008-088)资助
关键词
塔里木盆地
台盆区
三叠系
层序界面
体系域
地层格架
Tarim Basin； platform area； Triassic； sequence boundary； system tracts； stratigraphy framework
