Three-dimensional Structural Modeling Of The Dabei Area Of ??the Kuqa Fold-thrust Belt

Dabei areas is one of the main gas field of Tarim oilfield campany in kuqa area.In recent years,more studies accompany with more drilling data presents the Dabei structure is not a simple anticlinal,but is a more complex salt anticline with multi-imbricate thrusts developed underneath.In addition,further drilling data and well logging data shows many secondary faults were developed in the fault blocks,resulting in complex changes in the gas and water interface..Based on the precious studies,the modern geological structural theories,geometry analysis methods,balanced geological section technology,as well as the filed measured data,fine structural interpretation of Dabei anticline was conducted in this paper.Furthermore,the main periods of tectonic deformation was identified and reasonable fracture system was set up.Eventually,a three-dimensional geological model of Dabei Anticline was constructed.Research shows that the NE-SW trending Dawanqi anticline and the Tuzimazha anticline develop within Dabei area.The Tuzimazha anticline has different deformation characteristics in the upper and lower with T5reflection layer,Tuzimazha overlying the development of West dipping thrust fault,the overall structure of the North East high low;the T7-T5 reflection layer is a high profile with a high central area and a slightly irregular shape.Dawanqi anticline is the short axis of fold,the anticline moves towards the Eastand west to the west,and the uplift of the anticline is more obvious than of the shallow layer,to the surface of the anticline,the anticline is characterized by irregular undulation.As the tectonic units of the Dawanqi anticline and Tuzimazha anticline separated,salt diaper has been strong extrusion,showed a nearly east-west extension of the salt wall.The whole structure is NE-SW extension deformation fault and Tg reflection layer Dabei area under salt,salt under the overthrust nappe,salt bottom was lifted to the shallow tectonic development.The strongly developed squeezing structure under salt,the main development of a series of inbricate punching fragments and their super position structures from north to south thrust.Most of these thrusting fragments are NE-SW ward.In the north wing of the Dawaqi anticline,due to the welding of the salt and salt strata ande the local steering effect of the main fault plane.The pattern of fault surface has not always been consistent,instead,a serise of forward and reverse secondary faults are induced in the local position,making the local tectonic deformation enhancement.