3D fast fault restoration
AssigneeLandmark Graphics Corporation
InventorKaihong Wei
Life of this patent
Estimating the term…
Abstract
Solutions to the problem of reversing seismic fault movements are formulated using a model based on elasticity theory, and using finite element and boundary element methods for generating a solution. The solution involves defining slip vectors from known formations in the fault and applying a space constraint restriction to traction values on the fault surface. The method may be applied in either 2D or 3D applications. The method is computationally fast enough to allow interactive fault reversal, and permits experimentation with various unfaulting scenarios so that a geologically acceptable solution is provided.
Claims26
A computer-implemented method for reversing a seismic fault represented in a set of seismic data, comprising the steps of:
- receiving seismic data representing a formation volume that contains a fault surface;
- dividing the formation volume into two sections along a separating surface that includes the fault surface, wherein said dividing the formation volume includes specifying a set of geometric elements that cover the boundary of each section;
- receiving input data that specifies slip vectors at selected points on the fault surface;
- computing displacement vectors and traction vectors at vertices of the geometric elements of each section using said input data;
- determining displacement vectors at interior points of each section, wherein said determining a displacement vector at a given interior point of a given section includes numerically evaluating an integral equation over the boundary of the given section using the displacement vectors and the traction vectors at the vertices of the geometric elements covering the boundary of that section, wherein the integral equation is derived from the virtual work principle assuming elastic mechanical properties;
- and
- generating restored seismic data using the initial seismic data, the displacement vectors at the interior points of each section and the displacement vectors at the vertices of the geometric elements of each section;
- saving, storing, transmitting, or displaying the restored seismic data by a computer.
A computer-readable memory medium storing program instructions, wherein the program instructions are computer-executable to:
- receive seismic data representing a formation volume that contains a fault surface;
- divide the formation volume into two sections along a separating surface that includes the fault surface, wherein said dividing the formation volume includes specifying a set of geometric elements that cover the boundary of each section;
- receive input data that specifies slip vectors at selected points on the fault surface;
- compute displacement vectors and traction vectors at vertices of the geometric elements of each section using said input data;
- determine displacement vectors at interior points of each section, wherein said determining a displacement vector at a given interior point of a given section includes numerically evaluating an integral equation over the boundary of the given section using the displacement vectors and the traction vectors at the vertices of the geometric elements covering the boundary of that section, wherein the integral equation is derived from the virtual work principle assuming elastic mechanical properties;
- and
- generate restored seismic data using the initial seismic data, the displacement vectors at the interior points of each section and the displacement vectors at the vertices of the geometric elements of each section.
Dependencies are inferred from the claim text.