塔河桑塔木地区石炭系卡拉沙依组层序地层及砂体发育特征  

Sequence formations and sandbody development characteristics of Kalashayi Formation of Carboniferous in the Sangtamu Area of Tahe

作　　者：谢才铸 傅恒[1] 朱梦琦 王文博 XIE Caizhu;FU Heng;ZHU Mengqi;WANG Wenbo(College of Energy,Chengdu University of Technology,Chengdu,Sichuan 610059,China)

机构地区：[1]成都理工大学能源学院,四川成都610059

出　　处：《东北石油大学学报》2022年第4期1-11,I0001,共12页Journal of Northeast Petroleum University

基　　金：中国石化西北油气分公司科研项目(34400000-20-ZC0607-0001)。

摘　　要：结合测录井、地震资料,研究塔河桑塔木地区石炭系卡拉沙依组层序地层特征,探讨砂体发育特征与层序地层之间的关系,分析构造沉降、海平面变化及物源供给对层序地层及砂体发育特征的影响。结果表明:研究区卡拉沙依组发育于1个二级层序,可以进一步划分为6个三级层序(SQ6—SQ1),上泥岩段划分为1个三级层序(SQ6),砂泥岩段划分为5个三级层序(SQ5—SQ1),每个三级层序内部只发育海侵体系域和高位体系域;卡拉沙依组主要发育辫状河三角洲、浅海陆棚沉积相及水下分流河道、分流河道微相砂体,两种微相主要发育于SQ5—SQ1的高位体系域进积型三角洲平原与前缘亚相;纵向上,分流河道砂体呈条带状相互叠加,横向上,砂体相互拼接,有的呈叠加—孤立型,侧向上延伸不远;纵向上,水下分流河道砂体分布较宽,横向上,砂体延伸较广,整体较厚,连续性好,顺物源方向砂体厚度呈明显减薄趋势。构造沉降、全球相对海平面变化控制研究区三级层序的发育及其内部结构特征,进一步控制砂体发育;物源控制沉积物的充填,从而控制砂体垂向特征及演化规律。该结果为塔河地区石炭系研究及勘探提供指导。Combined with logging wells and seismic data,we studied the sequence strata of the Lower Carboniferous Kalashayi Formation in the Sangtamu Area of Tahe,discussed the relationship between sand development characteristics and sequence formations,analyzed the effects of tectonic settlement,sea level changes and material source supply on the development characteristics of sequence formations and sand bodies.The results show that the Kalashayi Formation in the study area can be further divided into 6 tertiary sequences(SQ6-SQ1)in a secondary sequence.The upper mudstone section is divided into a tertiary sequence(SQ6),and the sandstone section is divided into 5 tertiary sequences(SQ5-SQ1).Each tertiary sequence only developed the transgressive system domain and the high-level system domain.The Kalashayi Formation mainly developed braided river delta and shelf sedimentary facies.Two kinds of microphase sandbodies,the underwater shunt channel and shuntchannel,are mainly developed in the inflection delta plain and leading edge in the high-level system domain of SQ5-SQ1.The sand body of the shunt river shows strips of sand in the longitudinal superposition and horizontal splicing with each other,and some are superimposed or isolated,not far from the lateral extension.Longitudinally,the distribution of sand in the underwater diversion channel is wider,and the horizontal parting river extends wider,the overall thickness of the sand body is thicker and the continuity is good,and the sand thickness in the direction of the source shows a significant thinning trend.Tectonic subsidence and global relative sea level change control the development and internal structural characteristics of the third order sequence in the study area,and further control the development of sand bodies.Provenance controls the filling of sediment and thus controls the vertical characteristics and evolution of sand bodies.This result provides guidance for Carboniferous research and exploration in the Tahe Area.

关 键 词：层序格架 体系域 沉积相 砂体发育特征 卡拉沙依组 石炭系 桑塔木地区 

分 类 号：TE122.3[石油与天然气工程—油气勘探]