塔北草湖凹陷形成演化新认识及油气地质意义

《塔北草湖凹陷形成演化新认识及油气地质意义》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、学兔兔www.xuetutu.com专天然气比第34卷第3期OIL＆GASGE0LOGY2013年6月文章编号：0253—9985(2013)03—0370—06doi：10．11743／ogg20130313塔北草湖凹陷形成演化新及油气地质意义姚泽伟，何光玉，郑晓丽，漆立新2，张洪安，云露，林璐，王文侠(1．浙江大学地球科学系，浙江杭州，310027；2．中国石化西北油田分公司，新疆乌鲁木齐，830011)摘要：基于二维地震剖面的精细地质解释，并结合钻井资料的分析，提出了塔北地区古生代以来草湖凹陷形成演化的新认识，认为塔北草湖凹陷东、西两侧斜坡的形成时间与形成机理存在明显的

2、差异。凹陷西侧中一上奥陶统自东向西超覆沉积特征明显，表明西斜坡主要形成于加里东中期，形成机理是在持续区域挤压背景下，草湖地区相对沉降，阿克库勒地区相对隆升，表现出沉积型凹陷斜坡的特征；而凹陷东侧可见奥陶系、志留系等地层被强烈抬升并遭受剥蚀，角度不整合于上泥盆统一石炭系之下，后者又角度不整合于三叠系之下，表明东斜坡主要形成于加里东晚期和海西早、晚期的强烈构造变形，以海西晚期为主，表现出构造型凹陷斜坡的特征。草湖凹陷西侧有利于发育下奥陶统岩溶型地层圈闭，凹陷东侧有利于发育志留系、石炭系和三叠系超覆型岩性圈闭及中一上奥陶统不整合型地层圈闭、下奥陶统岩溶型地层圈闭，它们是下一步油气勘

3、探的重要方向。关键词：沉积型凹陷斜坡；构造型凹陷斜坡；油气圈闭；古生代；草湖凹陷；塔里木盆地中图分类号：TEl21．1文献标识码：ANewideasabouttheevolutionofCaohusaginthenorthernTarimBasinanditssignificanceforpetroleumgeologyYaoZewei，HeGuangyu，ZhengXiaoli，QiLixin，ZhangHong’an，YunLu，LinLu，WangWenxia(1．DepartmentofEaahSciences，ZhejiangUniversity，Hangzhou，

4、Zhejiang310027，China；2．NorthwestOilfieldCompanyofSINOPEC，Urumqi，Xinjiang830011，China)Abstract：TheevolutionofCaohusaginno~hernTarimBasinisdiscussedinthispaperbasedongeologicalinterpretationoftwo-dimensionalseismicprofilesandanalysisofdrillingdata．WepresentnewideasabouttheevolutionofCaohusags

5、incePaleozoic．ThetimeandmechanismofformationoftheeasternandwesternslopesofCaohusagareapparentlydif-ferent．Inthewesternsideofthesag，theMiddle—UpperOrdovicianshowdistinctoverlappingcharacteristicsfromeasttowest，indicatingthatthewesternslopeofCaohusagwasdevelopedmainlyintheMiddleCaledonianasth

6、eresultofthesubsidingofCaohuareaandtheupliftingofAkekuleUpliftunderthecontinuousregionalcompression．Thewesternslopehasthecharacteristicsofdepositionalsagslope．Whileintheeasternsideofthesag，theSilurian—OrdovicianwerestronglyupliftedanderodedandunderlieunconformablytheUpperDevonian-Carbonifer

7、ous，whichinturnunderlieunconformablytheTriassic．ThisdemonstratesthattheeasternslopewasdevelopedintheLateCaledonianaswellastheEarlyandLateHercynianastheresultoftheintensetectonicdeformation，withtheLateHercynianbeingthedominant．Theeast-ernslopeshowsthechar