Description: Two aspects of the characterization of turbiditic oil reservoirs based on geophysical models of their formation are discussed in this report. First, we have developed a new, more accurate and computationally faster finite-element method (FEM) for simulating the flow and deposition of turbidity currents. Although a finite volume method had been presented and discussed in a previous report, it was discovered to be insufficient for our purposes of simulating turbidity flows. The new method allows variable grids near the regions of large deposition, which are of most interest, and numerically results in banded, sparse matrices that are much faster to solve. Examples of the success of the method are presented. In the second part of this report, we present and discuss a preliminary study on the feasibility of matching the results of a sediment transport model to field data. With the simulation of the turbidity current we can create an entire turbiditic deposit. This requires the initial conditions of the flow, such as the amount of sediment, the volume or flow rate of the current, etc, which are of course unavailable. This requires an estimate of the initial conditions of the flow, which can be determined from limited data from the deposit. We used the Excel optimization routine Solver to reproduce a one-dimensional algebraically simulated deposit with and without measurement noise. Results indicate that such matching is feasible, provided that the noise is below certain thresholds, dependent on the size of the deposit and the number data points constraining the parameter estimation.
Date: June 1, 2003
Creator: Bonnecaze, Roger T. & Lakshminarasimhan, Srivatsan
Partner: UNT Libraries Government Documents Department