通过三维地震资料精细解释、钻井资料和地质资料综合对比分析，认为塔里木盆地玉北地区断裂系统主体表现为逆冲断裂。断裂主要在两个层次发育：一是发育在基底，构成基底断裂带或基底软弱带；二是发育在寒武系-奥陶系碳酸盐岩中的断裂带。玉北地区断裂系统由一系列呈北东东走向的断裂带组成，主要包括玉北7断裂带、玉北1断裂带、玉东1断裂带、玉东2断裂带、玉东3断裂带、玉东4断裂带等。单个断裂带往往由一条主断裂及其伴生的一组次级断裂组成。主断裂断面倾角上陡下缓，往深层在中-下寒武统盐岩层系中发生滑脱。主断裂和次级断裂常形成背冲型断裂组合，在剖面上构成“断垒”形态。寒武系-奥陶系碳酸盐岩断裂带主要形成于加里东中期，经历了加里东中期早幕（早奥陶世蓬莱坝期）、Ⅰ幕（早-中奥陶世鹰山期）和Ⅲ幕（晚奥陶世）3个幕次的活动，海西晚期断裂活动非常微弱。断裂带具有明显的分段变形特点，断裂系统和主不整合共同制约垂向构造分层。%Based on accurate 3-D seismic interpretation ,comprehensive analysis of the drilling and geological data ,it is in-dicated that the fault systems of the Yubei region in Tarim Basin are dominated by thrust faults .These thrust faults occur in two horizons .One is the basement where the thrusts consist basement fault zone ( or basement weak zones ) .The other is the Cambrian-Ordovician carbonates where a thrust zone occurs .The Yubei fault system consists of a series of NEE-trending thrust zones including Yubei No .7,Yubei No.1,Yudong No.1,Yu-dong No.2,Yudong No.3 and Yudong No.4.Each single thrust belt is often composed of one main thrust and a set of associated secondary thrust faults .The fault plane of the main fault dips steeply at the upper part and flattens towards the deeper part ,and detaches in the Mid-Lower Cambrian salt la-yers.The main thrust and its associated secondary back-thrusts commonly form pop-up fault assemblage showing “fault-horse” geometry on profile .These fault zones in the Cambrian-Ordovician carbonate rocks were mainly formed in the mid-Caledonian ,experiencing movement of the early-epoch ( the Early Ordovician Penglaiba stage ) ,Ⅰ-epoch ( the Mid-Early-Ordovician Yingshan stage ) , and Ⅲ-epoch ( the Late-Ordovician ) of the mid-Caledonian .The fault movement was very weak in the Hercynian .The fault zones are characterized by significant segmented deformation .The fault system and ma-jor unconformities jointly control the vertical structural layering .
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