摘要
北偏东走向的三危山横亘于敦煌盆地中部，将盆地分成了南、北2个部分，其生成与发育对两侧诸凹陷的构造特征及沉积充填有着直接的影响。因此，开展三危山演化特征的研宄对其两侧，尤其是五墩凹陷油气勘探具有重要的指导意义。通过对采自三危山不同位置和不同地层的13个样品进行磷灰石裂变径迹测年及热史模拟分析，三危山自志留纪开始隆升，经历了志留纪-早泥盆世快速冷却隆升、晚泥盆世-二叠纪缓慢冷却演化、三叠纪快速冷却隆升、侏罗纪缓慢冷却、白垩纪缓慢-快速冷却隆升与晚白垩世-新生代缓慢冷却共6个阶段。各阶段的发育特点与周边凹陷的沉积充填相辅相成，早侏罗世之前的2次快速隆升，对侏罗纪古地貌及物源体系有着重要的影响；侏罗纪时期缓慢冷却，表明区域构造活动趋于缓和，导致侏罗系断陷盆地开始发育；早白垩世晚期快速冷却隆升，表明区域处于挤压抬升背景，以至五墩凹陷上侏罗统、白垩系、古近系被剥蚀，烃源岩停止生排烃，对五墩凹陷洼陷带油气的生成及油气藏的形成与保存都有着重要影响。
The Sanweishan Area in the east-north strike was located in the middle of the Dunhuang Basin,by which the basin was divided into two parts from the south to north,and its formation and development had a direct impact on the structural characteristics and sedimentary filling of the sag on both sides of the basin.Therefore,the research on the evolution characteristics of Sanwei Area was of great significance for oil and gas exploration on both sides of it,especially for the exploration in Wudun Depression.Through the apatite fission-track dating and thermal history simulation analysis of thirteen samples collected from different positions and different strata in Sanwei-shan Area,the result showed that the Sanweishan Uplift was started since Silurian,and experienced six stages,including the rapid cooling uplift from the Silurian to the Early Devonian,the slow cooling evolution from the Late Devonian to the Permian,the rapid cooling uplift in the Tri-assic,the slow cooling in the Jurassic,the slow-rapid cooling uplift in the Early Cretaceous,the slow cooling in the Late Cretaceous-Cenozoic.The development characteristics of each stage and the sedimentary filling of the peripheral depressions were supplemented each other.The two rapid uplifts before the early Jurassic had an important influence on the Jurassic paleogeomor-phology and provenance system.The slow cooling up to Jurassic indicated that the regional tectonic activity tended to moderate,which brought the development of Jurassic faulted basin.The rapid cooling uplift after the Late Cretaceous indicated that the area was in a compressional uplift background,so that the strata of the Upper Jurassic,Cretaceous and Paleogene were eroded,hydrocarbon generating and expelling stopped in the source rocks.This has an important influence on the generation of oil and gas and the formation and preservation of the reservoirs in Wudun Depression.
作者
曹力伟
张敏
林中凯
刘国宏
李玮
Liwei Cao;Min Zhang;Zhongkai Lin;Guohong Liu;Wei Li(Research Institute of Exploration and Development,Shengli Oilfield Company,SINOPEC,Dongying Shandong;department of Geology,Northwest University,Xi'an Shaanxi)
出处
《石油天然气学报》
CAS
2018年第4期7-16,共10页
Journal of Oil and Gas Technology
关键词
裂变径迹测年
热演化
构造活动
三危山
沉积充填
油气藏
Fission-track Dating
Thermal Evolution
Tectonic Activity
Sanweishan Area
Sedimentary Filling
Hydrocarbon Reservoir
