准噶尔盆地东部地区构造演化与油气聚集

Structural evolution and hydrocarbon accumulation in the eastern Junggar Basin

应用地表地质、地震与钻井等资料,结合准噶尔盆地及周缘造山带的研究进展,对准噶尔盆地东部地区构造变形特征及构造变形的叠加过程进行了综合研究。结果表明,该区构造变形具有南北分带、东西分区,多期叠加的特点。南北向划分博格达山前、东部隆起与克拉美丽山前三大构造变形区。东部隆起构造变形区南北分为三大构造变形带,北部构造变形带为一组北东向展布的背斜与向斜构造,中部为北西西向展布古凸起,南部构造变形带发育受早期构造控制的近南北向构造,形成叠瓦状褶皱-断裂组合。该区经历了石炭纪的伸展断陷和南北向挤压变形,中生代的挤压走滑和新生代南北向的挤压等多期构造变形,具有挤压、走滑、逆冲推覆与膝褶褶皱等多种构造变形型式,划分为六大构造演化阶段。通过已发现油气藏的解剖,认为构造变形差异性、多期叠加古凸起、不整合和断裂等控制了油气的分布。

Surface geology,seismic and drilling data in combination with the research progress of orogenic belt in the Junggar Basin and its periphery were used to comprehensively study the structural deformation and its superinposition in the eastern Junggar Basin.The results show that the structural deformation in the study area is characterized by N-S zonation,E-W partition and multi-stage superinposition.From the south to the north,there are three major tectonic deformation regions of the Bogda front,the eastern uplift of the basin and the Kolameili front.To go a step further,the eastern uplift can be subdivided into three major structural deformation zones along N-S direction:the northern zone consists of a set of NE-trending anticlines and synclines;the central part is the NWW-trending paleo-uplifts;and the southern part is a nearly SN-trending structure controlled by early structures,forming a combination of imbricate folds and faults.The area has undergone multi-stage tectonic deformation such as the Carboniferous extensional faulted depression and SN-trending compressional deformation,the Mesozoic compressional strike-slip and the Cenozoic SN-trending compression.It contains varying patterns of structural deformation,such as compression,strike-slip,thrust nappe and kink-band,and chronologically,can be divided into six major tectonic evolution stages.Through the research of discovered oil and gas reservoirs,we considered that the factors controlling the distribution of oil and gas are structural deformation differences,multi-stage superimposed paleo-bulges,unconformities and faults.