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This paper presents a new depth migration method, adaptive spatial-division split-step Fourier (ASDSSF) migration. In this method we introduce the idea of a stratified phase shift migration into the split-step Fourier (SSF) migration to make an accurate and efficient wave field image when sharp discontinuities appear in the velocity field. In principle, the ASDSSF migration is a multi-reference slowness (reciprocal of velocity) (MRS) migration. Compared to previous MRS migration methods, this method uses fewer reference slowness values without accuracy loss. The reference slowness is determined in this paper according to an error-control parameter of the perturbation term in the SSF operator and the variation of the complet velocity field. The velocity corresponded to reference slowness can define a spatial division. Each division can also be divided into several discontinuous spatial subdivisions to effectively reduce the number of reference slowness values needed. The choice of reference slowness, including the number of reference slowness values needed and how to construct the spatial divisions, is adaptive and reasonable at each extrapolation step (depth step). A simple and economical smoothing filter in the wave number-frequency domain is designed to avoid artifacts in the wave field extrapolation due to the presence of sharp discontinuities in the velocity field. For comparable conditions the present approach to migration is expected to be computationally more efficient and accurate than other MRS migration methods. The performance of the method is demonstrated on a simple 2D prestack model and the prestack SEG/EAEG salt dataset.

With the implementation of the national strategy of “transportation power”, the transportation major is facing the transformation of new engineering majors. Practical education is an important link in the training of new engineering majors in application-oriented universities and plays a vital role in the quality of talent training. The transformation and upgrading of traditional majors has promoted the transformation of traditional school-enterprise cooperation to the integration of industry and education. Under the background of the integration of industry and education, the author puts forward some viewpoints, such as the precise orientation of talent training, the improvement of the system construction of practical education base, and the broadening of the practical education forms of the integration of industry and education. Taking Anhui Sanlian University as an example, This paper analyzes the practice and achievement of university-enterprise cooperative practical education construction for new engineering majors under the background of the integration of industry and education.

In this paper, we present a new migration velocity analysis method–synthetic source record interactive residual migration velocity analysis method based on controlled illumination. The differences between this method and other similar methods are: (1) The fast synthetic source record algorithm based on the wave theory is adopted in prestack depth migration; (2) The plane wave source is used in migration that is consistent with the velocity analysis method; (3) By using the controlled illumination, the distortion of the plane wave source wavefield due to the lateral velocity variation is avoided therefore the error of velocity analysis is reduced and; (4) The practical velocity spectrum makes the interactive migration velocity analysis feasible and convenient. The results of model and field data of Xinjiang prove that this method is valid and practical for migration velocity analysis.