Interactive Extraction And Visualization Of Horizon In Large-scale Seismic Volume

Visualization of seismic volume is a very important technology in petroleum exploration,and assists personnel in this field carry out geological exploration and analysis.As the key analysis,the 3D layer model object supports the extraction,display and prediction of geological horizon.But,large-scale seismic volumes often need to be performed with multi-resolution visualization,which makes horizon throughout the whole volume face the data space organized with blocks.How to interactively extract and visualize horizon quickly becomes an urgent problem.Aiming at PC platforms and large-scale multi-resolution seismic,this thesis proposes a fast horizon generation technology based on multi-level optimization by a given grid.Firstly,in the seismic level,a fast algorithm of layer triangle topologies and multi volume blocks intersecting detection based on the octree structure is designed.Then,in the single block level,an accurate intersection test based on the separation axis theory is performed.Finally,in the triangle mesh level,a space polygon clipping algorithm to finish intersection calculation and topology reconstruction is executed.In addition,by using a storage structure in which a number of grid cells share information such as a vertex list,the grid reconstruction efficiency in a multi-volume blocks is further optimized.Based on the above generation technology,the interactive extraction and visualization process of horizon is created in the realm of seismic acquisition design.One interactive response scheme based on blocks set judgment by octree subtree is proposed for viewpoint transformation and another interactive response scheme based on two stage rendering is proposed for horizon drag and drop.The experimental results show that the proposed method can effectively improve the interactive extraction efficiency while satisfying the display effect.Based on this method,for the grid and seismic volume data of different scale,layer for interaction can be generated quickly in multi-resolution seismic.At the same time,the robustness of visualization process and the fluency of the interactive operation can be ensured.