Structure Characteristics And Hydrocarbon Potential In Xide Area Of Xichang Basin

Xichang area is located in the eastern margin of the kangzang plateau,belonging to the snow mountain system and the daliang mountain system from the west to the east.It is located in the western margin of the Yangtze fault block,from dadu river in the north to the adjacent of ningnan and huili basin in the south.It is a tectonic basin,which is separated from sichuan basin,huili basin and chuxiong basin due to fault block difference.In terms of sedimentary structure development,xichang basin is closely related to sichuan basin.In this paper,the seismic profiles in xide area of xichang basin are interpreted by using a large number of seismic and well logging data,and the tectonic characteristics of the main structures(xide structure,qiliba north structure and luomu dashan structure)in xide area of xichang basin are analyzed and discussed.The geological situation of xide area in xichang basin is complicated,the geodetic structure inherits the complexity of the surface structure,the structure is developed,and there are many faults.From west to east,there are xide-xichang tectonic belt,mishi syncline belt,qiliba anticline belt,heishui river fault zone,luomu dashan-sikai tectonic belt and sikai fault zone.The tectonic belt to the west of the heishuhe fault zone is relatively simple,with positive and negative structures in north-south direction.The footwall of mi-shi fault is mi-shi syncline belt.The upper plate of the mi-shi fault and the footwall of the heishuihe fault are the qiliba tectonic belt.The two faults directly control the scale and distribution of this tectonic belt.Due to the influence of the heishuihe fault zone,the structure east of the heishuihe fault zone(including the heishuihe fault zone)is more complex,with strong folds,high,steep and narrow anticline and syncline,but generally distributed in the north-south direction.Its overall tectonic strength decreases from east to west.Xide in the main existing regional unconformity surface are sinian system and sinian system before,sinian system and Cambrian,Permian and silurian,emeishan basalt and maokou group,upper Triassic and the underlying palaeozoic era,representing the jinning movement,mangrove bay,the caledonian movement,the influence of the dongwu movement and indosinian movement,using the previous data and seismic interpretation,in this paper,the xichang basin tectonic evolution of xi district division.In this area,there are many sets of formation,storage and cover assemblages,and there are also many large traps,but the preservation condition is poor,which may not be able to form an ideal reservoir.