The Structure Characteristics Of Research And Physical Simulation In The North Of Songliao-Xujiaweizi Fault Rift Area

The Xujiaweizi rift is a large rifting in the northern deep layers of Songliao Basin.In recent years,the exploration research reveals that layers is extensive development and the drilling shows multilayer containing the gas.The stretch crack basin has good gas exploration prospect and is submitting reserves important realistic area.The sag basin has a strong segmentation.Each rifting basin has its own history of sedimentary and structural history,history of thermal and oil and gas accumulation.However,The Xujiaweizi rift period has strong structure activities and influence by late-stage volcanic activity.The late period structure reworking makes that rifting structure characteristics is very complex,basin evolution rule is not clear.In order to finding out the Xujiaweizi rift deep structure,the technology was adopted by structure and sedimentary sequence interface recognition,geometric analysis method and the principle of fault related fold.In the past,the structure research was ignored that the pre-existence structure had impact of the late late-stage structure deformation.Today's research shows that the late structure transformation often is controlled by the restriction of former structure.The Fault related fold is emphasized on the preexisting fault.On the basis of establishment of the unified structure stratigraphic framework?geometry?,the new theory was fully used such as,extensional structure,extrusion,inversion structure,double fault rift and fault related fold.The author was deeply studied to fracture systems,structural style and structure evolution?kinematic?sequence.The analysis of structural deformation genetic mechanism?dynamics?is according with the actual feature of structure formation in the Xujiaweizi rift.It will have a solid foundation for the next step oil and gas exploration.Finally,with combining the analysis of seismic section,the author thinks the following views:1.Through the combination of well–shock,on the basis of the original layer,the partial wells were adjusted.The key explanation object was identified within the structural sequence interface in Shahezi subgroups in the Xu JiaWeiZi rift.The priority of T₄₁,T₄₂ and T₅ sequence interface were given adjustments.The 3 sets of unconformity surface was identified within Shahezi subgroups.The uniform four stratigraphic framework was established.The shahezi subgroups can be bottom-up divided into the four strata:K₁Sh₁,K₁Sh₂,K₁Sh₃,K₁Sh₄.Firstly,the most obvious interface T₄₁b was identified,then T₄₁a,T₄₁c was identified.Up to this point,the shahezi subgroups four points was basic established.2.Structure style type in Shahezi subgroups in the XuJiaWeiZi rift mainly includes three kinds.It respectively concludes extend structure style,compression structure style and inversion structure style.The Extending structure style includes fault terrace?synthetic fault terrace and reverse fault terrace?,the graben horst combination,Y type combination,inverse traction fold and normal fault related fold five.structure styles includes three kind of Structure style type.It is detachment structure,thrust structure and reverse fault related fold.Inversion structure style includes positive and negative structure style.The Xujiaweizi rift has been proved that building period developed subsidence fault-related fold.The anticline was developed XuZhong uplift and syncline was taken shape XuXi rift and XuDong rift.Reworking period was developed the fault-bending folds.The mainly was developed sector on the southern tip on the Xu Zhong uplift belt,this type of fold was controlled thrust fault.This paper also revealed the formation and evolution processing of fault-related fold and fault-bending folds.Basics rift and uplift were controlled of fault-related fold,which have controlled of the formation and development of XuZhong uplift?XuXi rift and XuDong rift.The structural belt and partly structural role was controlled of fault-bending folds,which was favorable oil and gas accumulation.The Xujiaweizi rift pattern was developed the construction and reconstruction period of the fault structural layer.The extennding construction processing was experienced the layer of the Huoshiling,Shahezi and Yingcheng sedimentary construction period.The rift has experienced reconstruction processing of compression and inversion in the Shahezi and Yingcheng the late period sedimentary.Structure activity was weak after Yingcheng sedimentary subgroups and structure deformation was small,rift structure framework was influence of less.