Directional Illumination Analysis Of Combined Source Based On Wave Equation Simulation

Seismic data acquisition is an important link in seismic exploration,is the foundation of seismic data processing,interpretation,in recent years,with the deepening of the degree of prospecting and exploration of new area of the surface condition and underground structure becomes more complex,such as desert,mountain,plateau area,because the focus and the influence of factors such as high speed layer shielding,lead to field collection data of low signal-to-noise ratio,the serious influence image quality,the traditional common midpoint(CMP)is no longer applicable field data acquisition methods,in order to reduce the field seismic exploration cost,reduce risk,Need to adopt the method of a certain technology prior to simulation and analysis for the acquisition parameters of the exploration area,through the argument over and over again and applied research,provide theoretical guidance for the design of observation system and technical support to find an optimal observation system design method,and improve the accuracy of field exploration,improve image quality.Seismic illumination analysis is an important means to study the distribution of seismic wave field energy in complex structural regions and guide the design of observation system.In order to study the wave field characteristics of seismic wave propagation,the forward is indispensable,seismic numerical simulation method mainly divided into two major categories of ray tracing and wave equation method,due to the defect of the ray theory in complex high degree area light effect is very poor,and the numerical simulation based on the theory of the fluctuation due to use all the information in the kinematics and dynamics,wave field information is rich,high simulation precision,for any complicated geological conditions of region has very good lighting effect,so this article chooses is based on the wave theory of the wave equation of seismic illumination analysis.In this paper,on the basis of previous work,the wave equation of the finite difference time domain bulk chemical separation process carried out detailed research,rules of grid finite difference method is used for the second order,acoustic wave equation numerical simulation by using perfectly matched layer absorbing boundary condition to eliminate the influence of boundary reflection,is regular grid finite difference scheme of spatial derivative,the finite difference time derivative bulk chemical separation process is derived in detail,based on the different spatial difference precision,spatial grid spacing,time step,attenuation coefficient,frequency and different geological model of the acoustic wave equation forward modeling rules grid to prove the accuracy of the forward modeling.Directional excitation theory,from the array source array source direction factor is given and the relation between the parameters and excitation delay time expression,system research of the array source direction of seismic wave figure number,delay time to the source,formation rate,the relationship between the focal distance,gives the main lobe and sidelobe directional seismic waves and the definition of gate valve,through the study of the above parameters,thus to guide the combination of selecting parameters of the focal field work.Lighting analysis based on wave equation theory,the two-dimensional space is given array source seismic wave field and the calculation method of illumination,on the basis of the theory of poynting vector expression of acoustic wave equation is given,by a numerical example,analyses the combination of the source number of seismic wave field and the source and the relationship between the delay time,the source number,the more the more concentrated the direction of propagation of wave field,the delay time,the greater the wave field propagation direction and the vertical Angle is,the greater the In the end,the best method of shot point design is given by the relationship between the energy distribution of the seismic source field and various parameters of the combination of high-speed anomalous body model,horizontal layered medium model,thrust nappe model and two-dimensional complex marmousi model.