塔里木盆地满西地区寒武系台缘带演化及其分段特征

Revolution and segment characteristics of Cambrian carbonate platform margin in Manxi area,Tarim Basin

寒武系台缘带发育优质的礁滩体储层,作为塔里木盆地重要的油气勘探领域备受关注。首先根据地震反射结构特征和叠加样式,将满西地区寒武系台缘带划分为轮南—满参段、塔中32段和古城段3段;研究发现镶边台缘带最早形成于早寒武世晚期,仅分布在轮南—满参—塔中32段;中寒武世,古地地区发育弱镶边型台缘带,满西地区才形成统一的镶边台缘。其次分析了满西地区各段台缘带演化特征,其中轮南—满参段台缘带经历了由缓坡—弱镶边—加积型镶边—进积型镶边—抬升暴露的演化过程;塔中32段台缘带经历了由缓坡—弱镶边—加积型镶边台缘—弱进积型镶边台缘的演化过程;古城段台缘带则经历了由缓坡—进积型弱镶边台缘的演化过程。最后探讨了满西地区寒武系台缘带演化及迁移的控制因素,认为前寒武系古地貌、海平面变化主要控制了研究区台缘带的发育及演化。轮南—满参段的缓坡型台缘带及古城段的进积型台缘带为勘探的有利目标区。

Cambrian carbonate platform margin,where high quality reservoir developed,has attracted much attention as an important field of oil and gas exploration in Tarim Basin.Firstly,according to the seismic reflection structure and stacking pattern,Manxi platform margin of Manxi area can be divided into three sections：Lunan-Mancan section,Tazhong 32 section,Gucheng section.The study showed that the platform margin first formed in the late Early Cambrian,only distributed in the Lunnan-Mancan-Tazhong 32 section.In the late Middle Cambrian,the weak platform margin was developed in the Gucheng area,and the uniform edge was formed in the Manxi area.Secondly,the evolution of platform margin in each section of Manxi area was analyzed.The platform margin of Lunan-Mancan section underwent the evolutionary processes from ramp platform-weak edged platform margin-accretion type platform margin-progressive type platform to rim uplift platform.The platform margin of Tazhong 32 section underwent the evolutionary processes from ramp platform-weak edged platform margin：Accretion type platform margin to progressive type platform.The platform margin of Gucheng section underwent the evolutionary processes from ramp platform to progressive platform margin.Finally,the controlling factors of Cambodian platform margin evolution and migration in the Manxi area are discussed,pre-Cambrian paleogeomorphic and sea level changes mainly control the development and evolution of the platform margin of the target area.The ramp platform of the Lunnan-Mancan section and the progressive platform margin belt of the Gucheng section are favorable targets for exploration.