Geometry And Kinematies Of Eastern Part Of Southwest Tarim Basin

Eastern part of Southwest Tarim Basin is located in the southwest of the TarimBasin with an area of about15×104km2, which is in the north of central uplift, east ofthe Western Kunlun orogenic belt and Tiekelike uplift, and west of the Southeasternfault-uplift zone. The study area further can be divided into five third-order tectonicunits: Markit slope, Kashi Sag, Shache Sag, the Yecheng Sag and Southern KhotanmaSag. This thesis is mainly on the basis of fine interpretation of geological data on thesouthwest Tarim region, the use of fault-related fold theory with the study of theeastern part of the Southwest Depression of three structural geometry and kinematicsanalysis, combined with the geodynamic setting and regional tectonic features, andreference drilling and logging data, the deformation characteristics of three tectoniczones, the period of fault activity and the role of hydrocarbon traps in the controlstudy. This study constructed the geometry and kinematics models, recovered the finalregional tectonic evolution of the eastern region of southwest Tarim, and discussedhydrocarbon traps distribution characteristics, mainly to obtain the followingunderstanding:1. The MazhaTage tectonic zone detached with basement slip layers, thrust to theBachu Faulted-uplift through Markit slopes, and formed the fault-related folds.Slippages and thrusts of deep layers, fault propagation fold have suffered destructionand transformation by the post-basement-involved thrust faults of MazhaTage tectoniczone.2. Yubei1tectonic zone, with the overall presentation of the NE-SW direction,south arc protruding, shows a "Y" type cap slipping thrust fault propagation folddeformation style. Faults slippage began in the Cambrian gypsum and salt internalswith the local was propagation-turning mixed fault-fold.3. Southern Khotan thrust and nappe tectonic belt is consists of a top-down, fromsouth to north nappe, thrust the seats piece superposition of overlay the anticline dualtectonic system and weak deformation in situ. Generally, the thrust nappe tectonic beltis controlled by large-scale Detachment in the south of Khotan. From east to west of the under nappe, the deformation include the weak deformation to strongly involvedin deformation.4. From the point of view of the structural characteristics of the Eastern part ofSouthwest Tarim Basin, the tectonic evolution can be divided into five stages:1)Early Caledonian (Early-Middle Cambrian,) with the limitations of the carbonateplatform and evaporation platforms;2) Middle Caledonian (Late Cambrian-Ordovician) with ancient uplifts;3) Late Caledonian-Early Hercynian (SilurianPeriod-Middle Devonian) with uplifts formation;4) Hercynian (Carboniferous-Permian) with settlement burials;5) Himalayan (Cenozoic) with settlement tilteddeformation.5. Formation and evolution of Khotan ancient uplift played an important role inhydrocarbon accumulations in study area. The region has experienced three stages ofkarstification which was conducive to the formation and preservation of the reservoirs.While the Khotan ancient uplift occurred in the north and south lift ramp scalechanges by the Himalayan movements, provided the conditions for the formation oflarge karst-stratigraphic traps on Markit slope.