准噶尔盆地南缘古牧地背斜多期构造变形特征

古牧地背斜位于博格达山前阜康断裂带的北缘。为探讨博格达山隆升在沉积盆地内的构造响应特征,作者结合野外地表露头观测、地震反射特征和磷灰石裂变径迹分析,认为古牧地背斜垂向上可划分为深浅两大构造层:深层侏罗系西山窑组(J_2x)以下地层具有双重构造的特征,活动时间为150~130和100~80 Ma;浅层侏罗系西山窑组及以上地层具有断层突破型断层传播褶皱的特征,活动时间约为30 Ma。以上研究成果一方面反映出博格达山晚侏罗世以来多期构造活动的特点,另一方面反映古牧地背斜深层双重构造具有形成时间早、埋深相对浅的特点,是准噶尔盆地南缘有利的油气勘探领域。

Multiple Phase Deformation of Gumudi Anticline at South Margin of Junggar Basin

The Gumudi anticline is located at the north border of Fukang thrust belt,north piedmont zone of Bogeda Mountains.Combining with the outcrops,seismic and apatite fission track,we discussed the tectonic response of the sedimentary basin during the uplift of Bogeda Mountains.Vertically,the Gumudi anticline has dual structures:the layers below the Jurassic (J2x) Xishanyao formation were formed in 150-130 Ma and 100-80 Ma;while Xishanyao formation (J2x) and the above were formed in 30 Ma,with the features of propagation folds under faults breaking through.The results reflect that the multiple uplifts of Bogeda Mountains occurred after Late Jurassic,and the dual structure formation was formed earlier with shallower burial depth.The Gumudi anticline is a favorable area for oil and gas exploration in future.