Research On Three-Dimensional Geological Modeling And Seismic Wave Forward Modeling Considering The Complex Factors Of Near Surface

The establishment of a 3D geological model is conducive to understanding the geological attributes of any location underground.This article first reviews the historical background of 3D geological modeling.And with 3D geological modeling theory and method as the basic support point,using modeling data such as borehole data,seismic record data,seismic interpretation section,geological section,borehole wave velocity map,etc.in the study area,taking into account the complex factors near the surface,The stratum with a depth of less than 100 m in the study area mainly relies on the drilling data of the study area for modeling,and the stratum with a depth of 100 m or less mainly relies on the controlled drilling of the predecessors near the study area.Taking into account the positional and spatial relationship between interpolation points and sample points in the modeling process,this article uses the ordinary Kriging interpolation method in geostatistics to discuss and compare the common types of variograms,and conduct crossover Verification,determined the ordinary Kriging interpolation using a spherical model to simulate the variogram,using this type of interpolation method to interpolate the insufficient boreholes,so that the data distribution in the entire study area is more continuous and uniform,and the interpolation is not the same Part of the layer data adopts the geometric adaptation method in discrete smooth interpolation.This method can automatically adapt the data to a more appropriate layer,compare the established three-dimensional geological body with the reserved borehole data,and fine-tune the geological model.In order to further verify and optimize the model,this paper adopts the method of seismic wave forward simulation.Considering that the existing seismic data is mostly two-dimensional,the model is cut along the NS and EW directions and imported into Tesseral,and the corresponding earthquake is obtained using the wave equation theory.record.Compare the slope and depth of the refraction wave obtained from the borehole data with the original seismic record,adjust the bottom interface of T2 and the longitudinal wave velocity;compare the depth profile of the seismic record simulated by the T3,T4,and T5 interface with the depth profile of the original seismic record For comparison,adjust the depth and longitudinal wave velocity of each layer.Import the optimized profile into SKUA,and use the method of profile modeling to establish a more accurate three-dimensional geological model.