Study On The Method Of Complex Geological Object Block Modeling

The main task of seismic exploration is realizing the imageing of underground structure. This mainly depends on migration. The success or not mainly relies on the wave background parameter. In these parameters, the speed is most important one, because it relates closely kinematics and dynamics characteristic of reflection signal. Layer velocity modeling is not enough for high accuracy pre-stack imaging. But block velocity modeling accurately describes subsurface complex geological structure. Through the research of seismic exploration complex geological object block modeling method, this paper proposes a new practicable workflow about block modeling, and has given each kind of core algorithm about it.The Delaunay triangulation is antithesis of Voronoi Diagram with a space optimization structure, the strict mathematics definition, the complete basic theory and good feasibility. Through researching 2D Delaunay triangulation, this paper achieves Bowyer-Watson algorithm and constraints regularization. This algorithm maintains the consistent between Delaunay triangulation and the constraints in the geometry, has solved surface structure geometry modelling questions about geological horizon and fault, has guaranteed the spatial uniformity of geological horizon and the fault.Through the research of Curved Surfaces Intersection, sutures, cutting and the uniform output technology, this paper has given the detailed algorithm, has realized the block body geometry superficial modelling, has formed the block geometry surface triangle grid. First, this paper proposes the surface intersection algorithm based on Delaunay triangulation with the bounding box and surface boundary extension method, this algorithm keeps geologic position of the spatial relations of geological horizon and fault. Second, According to the needs of classify the various suture problems, this paper proposes and implementes the stitching algorithm based on a single boundary surface and double boundary surface. Third, this paper proposes and implementes a kind of division algorithm based on the spread of triangle, with thinking the characteristics of Delaunay triangulation. Final, it Achieves uniform output surface algorithm, and ouputs the Delaunay triangulation grid owned by one closed block through Curved Surfaces Intersection, sutures, cutting.Based on the block geometry surface triangle grid, this paper researches solid modeling technology, gives the 3D Delaunay triangulation algorithm and 3D constraint Delaunay triangulation algorithm. This algorithm solves complicated geologic object modeling problem. Based on the complicated geologic object triangle grid model, this paper researches Inverse distance weighted interpolation, DSI interpolation and Kriging interpolation technology. Using block body model and velocity control point, it realizes the Kriging interpolation of seismic imaging velocity depth block model.In order to achieve software integration of three-dimensional seismic modeling module, this paper references the advantages of seismic exploration software development platform at home and abroad, approves and realizes a new standardized and effective method for developing the seismic function modules, by analysis and study of data structure and common characteristics of seismic data and function modules. Standardized input-output interfaces of parameter and data about seismic exploration function modules are provided between C and FORTRAN language. Standardization of the use of input-output interfaces, XML parsing engine and source templates technology enable seismic exploration function modules to program automatically, and a powerful seismic function modules standardized development tools are launched.Using complex geological object block modeling algorithm, this paper established CB30, ZH,YX area velocity-depth model in Shengli Oil field, provides accurate velocity-depth model for accurate imaging of these areas. Imaging result show that the research and realization of three-dimensional complex geological object block modeling algorithm is correct and effective.Finally, this paper presents three-dimensional block velocity modeling in the next step in technology development, particularly, introduces the use of heterogeneous multi-core CPU + GPU to achieve efficient parallel computing technology and the importantce of a three-dimensional seismic velocity modeling interactive tool.