Construction of compositional geological models using the variational grid method of geomapping and the object-hierarchical approach

Abstract

The variational grid method of geomapping is based on approximation by bicubic splines, the permissible grid size of which is limited by the amount of computer RAM. The paper describes an approach to solving problems of constructing maps of geological parameters, using this method, when computer resources are insufficient. The approach is based on the sequential mapping for a set of fragments of the entire mapping area. The implementation of the approach is considered for two options. The first, if the data density is sufficiently high, consists of sequential calculations over partially overlapping “bands”. If the data distribution is significantly uneven, the second option is implemented, which consists in calculating a detailed grid for local areas and smoothly pasting it into the general map. Smoothness at the boundaries of bands and insets is ensured through the condition of equality of spline coefficients for coinciding nodes, which is set by adjusting the system of linear algebraic equations when solving the mapping problem. Based on these approaches, a multiscale structural-geological model of the sedimentary cover over the territory of Western Siberia was implemented. The formation of a compositional model is carried out on the basis of an object-hierarchical approach, which ensures consistency in the calculations of all its elements, as well as automation of constructions.