Curvilinear Depositional Coordinate System for Geological Modeling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for modeling geological terrains in oil reservoir geosciences fail to accurately represent the chronostratigraphic environment at the time of deposition due to distortions caused by erosion and tectonic deformations, leading to inaccurate interpolation of properties like porosity and permeability.
Innovation Solution
A method is proposed to compute a curvilinear depositional coordinate system using mechanical deformation simulations, which honors the properties of planar isochrons and removal of post-depositional deformations, allowing for a physically reliable computational space where Euclidean distances match geodesic distances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If geostatistical methods are applied directly to the present-day space using Cartesian coordinate system, then the modeling process is simple, but the interpolation accuracy deteriorates because Euclidean distances do not match geodesic distances at the time of deposition
Solution Approach 1:
The patent transforms the coordinate system from Cartesian (x, y, z) to curvilinear depositional coordinates (u, v, w) that account for tectonic deformations. This parameter change in the coordinate system allows distances in the computational space to correspond to geodesic distances at the time of deposition, thereby improving interpolation accuracy while maintaining computational feasibility through numerical methods
Solution Approach 2:
The patent introduces a depositional space as an intermediate computational environment between the present-day geological space and the target property modeling. This intermediate space, defined by curvilinear coordinates, serves as a mediator where geostatistical interpolation can be performed accurately by mapping present-day coordinates to depositional coordinates and back, resolving the contradiction between simplicity and accuracy
2Measurement precision
If a curvilinear depositional coordinate system is used to remove tectonic deformations, then the interpolation accuracy improves, but the computational complexity increases
Solution Approach 1:
The patent performs preliminary computation of the curvilinear coordinate transformation and its derivatives before the actual geostatistical interpolation. By pre-calculating the coordinate system parameters and storing them for reuse, the method reduces the computational burden during the interpolation process itself, making the complex approach more efficient
Solution Approach 2:
The patent replaces the need for complex real-time coordinate transformations during interpolation with pre-computed transformation parameters and lookup tables. This substitution reduces computational complexity by transforming a dynamic complex operation into a series of simpler, pre-prepared operations that can be efficiently executed
3Ease of operation
If the present-day geometry of geological domain is used, then the data acquisition is easier, but the computed distributions of physical properties become inaccurate due to erosion and faulting
Solution Approach 1:
The patent inverts the conventional approach by not trying to interpret present-day geometry directly, but rather by computing a virtual depositional geometry that represents the paleo-environment. The method works backwards from present-day coordinates to depositional coordinates, applying inverse tectonic transformations to reconstruct the original depositional configuration, thereby improving paleo-environment representation while using easily acquired present-day data
Data Source
Figure 1~2
Figure 3~4(b)
Figure 5(a)~5(d)
AI summary
The present invention concerns a method for building a depositional space corresponding to a geological domain, comprising the steps of (i) partitioning the present day geological domain with at least one conformal mesh sensibly matching the boundaries of said geological domain, (ii) calculating depositional coordinates defining a depositional space, wherein said depositional coordinates calculations comprises calculations of fields of displacement including simulations of mechanical deformations in the geological domain, using a solid material deformation model. The present invention concerns also a computer program implementing the method.