摘要:本文通过研究区深层主要变形带构造变形解析，确认塔东南下古生界构造基本轮廓形成于中奥陶世末，定型于奥陶纪末—志留纪，北部和西部分别有喜山期和海西晚期构造的叠加。以塔中Ⅰ构造带—塔中5-38井构造带、塘北—玉北构造带、塔中南缘构造带为界，研究区可分为4个构造样式不同的构造单元。单元边界的构造变形相对剧烈，以逆冲—走滑断裂带为主，单元内部构造变形相对较弱。自东南向盆地内部，构造变形由强变弱。东南边缘塘沽巴斯凹陷以弧形向西北展布的基底滑脱型逆冲构造为特征，变形最为剧烈。晚奥陶世以凹陷为主，奥陶纪末期志留纪褶皱隆起。北侧为塔中隆起，是一个断裂—褶皱复背斜，主体发育于中奥陶世晚期，缺失中奥陶统，且控制了上奥陶统良里塔格组沉积时期孤立台地沉积，于奥陶纪末—志留纪定型。构造带以基底卷入扭动挤压断裂—褶皱变形为主，总体受控于北缘断层，自西向东逆冲幅度增大，西部为南北对称复背斜，东部形成向北逆冲的构造带。塔中隆起西段自北向南由逆冲挤压向压扭性走滑构造转变。西部巴楚东段及塔西南东部以区域性的隆升为主，与塔中隆起相似，大面积缺失中奥陶统地层。北部顺托地区则以走滑断裂发育为主，断裂主要活动期为奥陶纪末—志留纪和海西晚期。构造变形组合显示，塔东南下古生界构造变形动力主要来自盆地东南部，是东昆仑与阿尔金洋渐进闭合、俯冲碰撞过程导致塔里木板块变形的产物。变形时序及研究区NE向断裂运动规律表明板块作用自中加里东至晚加里东持续压扭的过程。塔东南地区各单元构造样式与强度差异表明盆地盖层变形明显受到基底断块与内部寒武系膏泥岩分布的制约。其次，断裂的多期活动体现了后期构造的叠合改造的作用，顺托地区NE向断裂可能与海西晚期构造运动的延展有关。
关键词: 构造带/
构造样式/
变形体系/
影响因素/
塔中地区
Abstract:By analyzing the study area mainly tectonic belt in the southeast, rudiment structure of Lower Paleozoic era was formed in the late of Middle Ordovician, finalize structure was formed in the Late Ordovician to Silurian period, the west and the north of the southeast was superposed and reformed by Himalayas and Variscan period tectonic. Survey region can be divided into 4 region composed of seven different structural style, dividing line respectively are TZ1 structural belt-well TZ5-38 Tangbei-Yubei structural belt, and south margin fault of the Tangzhong uplift. Tempestuously reform spread unit margin, inter reform are week deformation towards the basin gradually weakened. The strongest in Tanggubasi sag, consisted of arc thrust-folds belts involved basement and towards the basin. Tanggubasi sag was depression before Ordovician, came true fold uplift since late of Ordovician to Silurian. The Tazhong uplift by Tanggubasi sag to the south is compound fold, was formed in late of Middle Ordovician, was loss of Middle Ordovician and controlled deposition of isolate platform in Lianglitage group of Late Ordovician, finalize shape was formed in Late Ordovician-Silurian. The belts are consist of wrench and thrust styles, was controlled by the north faults which thrusts intensity toward east, symmetrical compound fold in west, thrust toward north in east. From north to south by the thrust to the shear strike-slip tectonic. East Bachu uplift and East Taxinan uplift are lift, Middle Ordovician is absent, which is similar to Tazhong uplift. strike-slip faults are main characteristic in Shuntuo area, active period are late of Middle Ordovician-Silurian period and Permian. It can be deduced this tectonic system was a result lead by tectonic dynamical from Aerjin and Kunlun see plate tectonics. It indicates by time series of the transformation system and movement of the NE faults that acting force of the plate tectonics sustain from Middle Ordovician to Silurian period. Region difference include structural styles and intension indicated that the transformation were controlled by base structure and detachment layer consist of Cambrian gypsum-mud rock strata. Multiperiodic activity of the most faults indicated that the late tectonic movement play important role, the extension of NE faults might be related Late Variscian movement.
Key words:Structural belts/
Structural styles/
Deformation system/
Impact factors/
Tazhong area
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