Calculation Of Unconformity Surfaces' Denudation Thickness In Binbei Area Of Songliao Basin

Calculation of strata denudation is an important and basal research task of basinanalysis. Strata denudation greatly affects formation, movement and conglomerationof oil and gas in deposit basin and changes the filling of original deposit basin, thenconfine the research which contains the history of basin's structure evolvement, thehistory of basin's filling, the history of deposit evolvement, heat history and thehistory of becoming store of oil and gas. Methods of Calculation strata denudation in the basin may be divided into thegeology method, the geochemistry method and the geophysical method. Thegeology method is a kind of traditional calculation strata denudation method.Geology observation is the most direct and credible method that differentiates touchrelation of strata and confirms the magnitude of denudation. In general, theconclusion of rational calculation is more credible, according to this. It requests theresearcher to full acquaint the history of structure evolvement and the history ofdepositing in the work of restoring strata denudation using geology method Becausethe choice of the concrete method depends on the characteristics of basin structureevolvement and sediments. The method of sedimentation rate and the method ofaccording to disdenuded strata's trend are frequently used in geology method. Thegeophysical method is the method of calculating strata denudation thickness whichbases on the curves that various physical parameters, such as porosity, density andwave velocity, vary with depth by means of geophysics, suck as well logging, seism IV论文摘要etc. The method of interval transit time is frequently used in geophysical method.The geochemistry method is the method of utilizing that geochemistry index existsbreak that appears between unconformity surfaces' up and down strata andcalculating strata denudation thickness obtained from the break information. Themethod of organic geochemistry index (such as Ro), the method of apatite fissiontrack, the method of cosmogenic nuclide are frequently used in geochemistrymethod. Above every kind of method that is limited by particular geology conditionwhich makes it existing very big localization, so it should progress general researchsynthesizing every kind of method when strata denudation is restored. The structure evolvement of Binbei area can be divided into five evolvementphases which contain substrate formation phase (before Triassic), extrusionapophysis phase (T-J1), fault basin formation phase (T2-K1), depression caused byregion heat flexure phase (Denglouku-Nenjiang stage) which contains sub-phase(Denglouku stage) and depression sub-phase (Quantou-Nenjiang stage) and basintransference and shrinkage phase (Sifangtai-Mingshui stage). After above fiveevolvement phases in Binbei area, it forms a series of structure unconformitysurfaces in which T5, T4, T3, T2 and T1 unconformity surface are more important. T5 unconformity surface is tip surface of substrate. Because T5 unconformitysurface undergoes fold function, metamorphism function and long-playingdenudation, lithology and substance of substrate greatly changed, which makesmany methods cann't be used. Withal, we should make much better of the up anddown strata information of T5 unconformity surface when we restore denudationthickness of T5 unconformity surface. We adopt the method of volume balance-sedimentation rate during restoring denudation thickness of T5 unconformity surface.The characteristic of denudation thickness' ichnography of T5 unconformity surface V吉林大学硕士学位论文in Binbei area is that denudation thickness in east, west and north area is bigger anddenudation thickness in middle area is smaller in region distribution. Thecharacteristic of denudation thickness ichnography of T5 unconformity surface inBinbei area is that denudation thickness in the area where unconformity...