Application Of Well-seismic Response Analysis In Sand Body Prediction Under The Control Of Sedimentary Facies

Correct prediction of reservoirs is the most important foundation for delineating reservoirs.The geological environment for reservoir development is complex,and many problems remain to be solved.Aiming at the difficult problems in the seismic identification and prediction of lithologic reservoirs in the study area LT depression,this paper adheres to the theory that seismic reservoir prediction should be studied from the perspective of seismic multi-information,using logging curves to screen lithology,comprehensive analysis Rock physics characteristics,attribute analysis and other technical means to more reliably describe the morphological characteristics of sandstone,comprehensive information on geology and earthquakes in the most favorable development areas of siltstone,using multi-parameter,multi-information,multi-method comprehensive prediction technology To reliably implement the morphological characteristics of the "dessert".The main research contents and research results are as follows:The well logging data of each phase zone reservoir of LT were studied in detail,and the standard parameters of each phase zone reservoir were extracted as the basic data for demonstrating physical calculation.Guided by the theory of sequence stratigraphy,in the isochronous stratigraphic framework,the sand layer group is taken as the basic unit to study the sand body distribution characteristics,and the lithology group of the typical section is studied.Exploring the single-interface seismic response decomposition method,analyzing the influence of the single reflection interface on the seismic reflection wave group in the sedimentary strata,and then establishing the reservoir seismic reflection mode,and analyzing the sand-shale velocity difference and seismic identification characteristics of the Shasan Formation in the Liutun area.And dissect the seismic waveform response characteristics of typical reservoirs for existing work.The two-dimensional seismic section sequence frame is restored,the geological model is established,and the typical reflection characteristics and sand body identification in the seismic sequence frame are analyzed.The short-axis discontinuous weak amplitude reflection in the shallow part is the distributary channel sand,and the deep part is reflected as mudstone.Smooth continuous strong amplitude reflections are mudstone or salt rock.Finally,the seismic attribute calculation and analysis is carried out under the guidance of the lithology combined phase control model.The predicted sand body thickness and the sand group statistical thickness are not much different,and the reservoir sand body thickness is successfully predicted,which provides a scientific basis for oil and gas exploration and development in LT depression.