摘要
针对准噶尔盆地南缘深层钻井少、地震成像复杂、勘探程度低而导致的原型盆地岩相古地理研究困难、沉积砂体展布范围可信度低的问题,基于源-汇思想,使用新方法开展岩相古地理恢复与砂砾岩体分布预测研究,应用磷灰石裂变径迹年龄确定宏观物源区范围与隆升时间;依据砾石径与搬运距离定量关系、构造缩短量等地质参数,恢复物源区范围、湖岸线迁移过程;开展钻井岩心与野外露头沉积构造等分析,编制岩相古地理演化与砂砾岩体分布范围系列图件。早侏罗世—早白垩世,准噶尔盆地南缘物源区范围由南向北逐步扩大,湖盆经历扩张—萎缩—扩张、古气候经历潮湿—干旱—潮湿的演化过程。西段一直发育来自南部古天山物源的近源扇三角洲沉积,中段与东段物源区具有由远源到近源的演化特征,主要发育河流—三角洲、辫状河三角洲、扇三角洲等沉积;西段与中段物源区的分界线推测为红车断裂带。恢复出的古湖岸线与现今盆地边缘线呈向西北敞开的夹角,控制了其两侧三角洲平原相带与前缘相带储集体的非均质性,湖岸线与现今地层剥蚀线、盆地边缘线限定了有利储集体的类型与范围。该认识可为准噶尔盆地南缘深层下组合油气勘探提供地质参数依据。
In view of the difficulties in the study of lithofacies paleogeography and the low reliability of the distribution range of sedimentary sand bodies in the prototype basin caused by less deep drilling,complex seismic imaging and low degree of exploration in the southern margin of Junggar Basin.A new method based on the source to sink idea was used to restore lithofacies paleogeography and predict glutenite distribution.In the restoration,apatite fission track age was used to define range and uplift time of macro-provenance;the range of provenance area and the migration process of lake shoreline were restored based on the quantitative relationship between gravel diameter and transportation distance,tectonic shortening and other geological parameters;drilling cores and field outcrop sedimentary structures were analyzed,and a series of maps of lithofacies paleogeographic evolution and distribution range of glutenite bodies were compiled.It is concluded that from Early Jurassic to Early Cretaceous,in the southern margin of Junggar Basin,the provenance area gradually expanded from south to north,the lake basin expanded,shrunk and expanded,and the paleoclimate changed from humid to drought to humid.The western section always had proximal fan delta deposits from the southern ancient Tianshan provenance developed,and in the middle and eastern sections,the provenance areas evolved from far source to near source,mainly river-delta,braided delta,fan delta and other sediments developed.The boundary between provenance areas of the western and middle sections is speculated to be Hongche fault zone.In an angle open to the northwest with the current basin edge line,the restored ancient lake shoreline controlled the heterogeneity of reservoirs in the delta plain belt and delta front belt on its both sides.The ancient lake shoreline,current stratigraphic denudation line and current basin margin line limit the types and scope of favorable reservoirs.This understanding provides an important geological basis for oil and gas exploration in the deep lower source-reservoir assemblage at the southern margin of Junggar basin.
作者
高志勇
石雨昕
冯佳睿
周川闽
罗忠
GAO Zhiyong;SHI Yuxin;FENG Jiarui;ZHOU Chuanmin;LUO Zhong(Petroleum Geology Research and Laboratory Center,PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;State Key Laboratory of Enhanced Oil Recovery,Beijing 100083,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2022年第1期68-80,共13页
Petroleum Exploration and Development
基金
国家科技重大专项(2016ZX05003-001)
中国石油天然气股份有限公司课题(2019B-0505,2021DJ0202,2021DJ0302)。
关键词
准噶尔盆地南缘
深层下组合
侏罗系
白垩系
物源区
湖岸线
岩相古地理
有利砂体展布
southern margin of Junggar Basin
deep lower assemblage
Jurassic
Cretaceous
provenance
lake shoreline
lithofacies paleogeography
favorable sandbody distribution
