Abstract:

The use of hybrid techniques aims at constructing new models which enable us to overcome the existing limitations in the reproduction of curvilinear structures. Improvements on a deepwater turbidite reservoir model combining several primary modeling methods are presented. In the initial approach, multiple points geostatistics (MPS) plays an important role in simulating and conditioning the realizations.

The new approach overcomes the limitations found in the MPS usage by combining surface-based (SB) methods with object-based (OB) simulation. Representation of flow direction and calculation of upslope areas on the rectangular grid elevation model are used to determine the drainage basin and simulation area (SA). The SA is then used to relate the previously simulated surface with the current geological event being simulated. The procedure is based on representing flow direction as a single angle taken as the steepest downward slope on eight triangular facets centered at each grid point. For a given anchor point joining the channel to the lobe in the channel-lobe parameterization, we obtain the influence and dependence area in a sequential process. The contour of the newly generated SA along with the cumulative density functions (CDF) retrieved from a process-based model output are employed to introduce variability to the OB geobody simulation. This procedure is repeated as many times as lobes are to be simulated, only updating the current base topography.

The improved model emphasizes using more realistic geological rules, especially on lobe orientation and erosion caused during the deposition of the geobodies. The lobe erosion process is simulated in such a way that flow direction and special topographic features related to the flow erosional power are accounted for. Objective rejection rules are taken into account in the implementation of the model. This gives rise to an automatic and user vi independent algorithm. This approach is potentially capable of representing the internal features of the geobodies.

With respect to the model conditioning, area expansion and a novel grid deformation approach are used to lead geobodies to the data location in such a way that the facies and thicknesses observed in core data are honored. Finally, a simple but efficient and geologically consistent property population algorithm is introduced.

Press the Back button in your browser.

Copyright 2009, Alejandro D. Leiva: Please note that the reports and theses are copyright to their original authors. Authors have given written permission for their work to be made available here. Readers who download reports from this site should honor the copyright of the original authors and may not copy or distribute the work further without the permission of the author, Alejandro D. Leiva.