Print this pageEfrain Mendez-Hernandez1, Javier Mendez-DeLeon2, Martine Da Silva3, Yves Lafet4
(1) Pemex Exploracion y Produccion, Villahermosa, Tabasco, Mexico
(2) Pemex Exploracion y Produccion, Reynosa, Tamaulipas, Mexico
(3) Compañia Mexicana de Geofisica, Villahermosa, Tabasco, Mexico
(4) Compagnie Generale de Geophysique, Massy Cedex, France
ABSTRACT: 3D Seismic Inversion as a Tool to Optimize the Exploration Risk Analysis at Burgos Basin, Mexico
An integrated 3D seismic inversion study was conducted at Burgos Basin, Mexico, to provide an understanding of the seismic amplitudes and their relationship with the spatial distribution of porosity, lithology and the presence of gas. Sandstones, of Paleocene age, produce gas on an environment of faulted basin floor fans at a depth of approximately 2900 meters. Lateral heterogeneity makes reservoir detection and delineation difficult in the inter-well space. A key point of the study was to assist in verifying the proper location of two proposed drilling locations.
The available well information was employed to calibrate a well-preserved seismic amplitude cube. Zero-phasing wavelet estimation, at reservoir level, followed the process to obtain an initial macro-model of acoustic impedance. A feasibility analysis determined that the acoustic impedance is a good attribute to explain amplitude variations in terms of reservoir properties. Before the full inversion was performed, the inversion parameters were adjusted on small seismic cubes around selected well locations. Final inversion results, from a global optimization technique, provided a 3D high-resolution model of acoustic impedance that was interpreted using an interactive workstation.
After calibration with both well log information and production data, low acoustic impedance was associated with gas bearing sands containing high porosity values. Seismically, an amplitude anomaly strongly correlates with a low impedance trend. The integrated approach allowed more efficient planning indicating that one of the proposed locations has a good opportunity for success whereas the second location is not recommended for drilling.
AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado