准噶尔盆地结构及其圈闭类型

准噶尔盆地是复合叠加前陆盆地 ,其原型分别形成于板块俯冲、碰撞、造山带后期复活、拗拉槽回返和板内皱陷作用有关的大地构造环境。其古生代盆地的形成与相邻的阿尔泰山和东、西准噶尔山、天山及博格达山的造山作用相关。中新生代盆地的形成和改造与其南部特提斯域板块俯冲碰撞造山引起的盆地相邻造山带的复活有关。相邻造山带时空上不均一的造山作用对盆地的影响不同 ,形成了盆地独特的结构。各坳陷均由与其形成有关的造山带前缘冲断带、陡坡带、山前凹陷、缓坡带和前隆及前缘皱陷等构成 ,前隆之间的叠加构成了盆地的大型隆起 ,皱陷叠加构成了盆地的中央坳陷。不同类型的圈闭在坳陷中有规律地分布着

STRUCTURE AND TRAP TYPESOF JUNGGAR BASIN

Junggar basin is a composite overlapping foreland basin,whose prototype formed in the associat- ed geotectonic settings,i.e.,subduction and collision of plates,late reactiviation of orogenic belts,invertion of aulacogen,and intraplate folding and depression.The Paleozoic prototype is related with the orogeny of the surrounding Altay Mts.,East and West Junggar Mts.,Northwest Tianshan Mts.,and Bogda Mts.. The Meso- Cenozoic prototype is associated with the reactiviation of neighboring orogenic belts caused by northward subduction and collision of the plates of Tethys domain.The inhomogenous orogeny in time and space of the adjacent orogenic belts forms the peculiar structure of the basin.All downwarpings are composed of frontal margin thrust zone,steep slope zone,submountain depression,gentle slope zone,frontal uplift and frontal margin folded depression,etc.The overlapping of frontal uplifts formed the large scale uplift of the basin,and that of folded depression formed the central depression of the basin.Different types of traps are spread regularly in the downwarpings.