Richard Salter1, Marc Beller1, Dianna
Shelander1, Ben Flack1, Diana Gillespie1,
Francisco Pineda2, and Jose Camara2
1 Reservoir Services/DCS, Schlumberger, Houston, TX
A high-resolution seismic survey covering 320km2 over the Arenque and Lobina fields was acquired with the express intention of helping to guide new well locations. This survey obtained significantly higher frequency content than conventional seismic data over the field area with a maximum frequency of 60Hz at 2.5s compared to 30Hz previously obtained.
The resolution and fidelity of the seismic data enabled an enhanced interpretation that provided a much clearer understanding of the structural and stratigraphic controls over the survey than had been possible to interpret using the conventionally acquired and processed seismic data. The ability to map discretely key reservoir units provided a structural framework through which reservoir properties could be accurately mapped. A robust inversion workflow was employed to maximize the use of the data. Numerous wells were used in the study to help determine reliable petrophysical transforms that could be applied to the inverted P-wave impedance to obtain highly quantitative porosity measurements.
The quantification of porosity development in the Cretaceous Tamaulipas and Jurassic San Andres reservoirs has provided substantial and valuable assistance in identifying new prospect areas as well as reducing risk in the assessment of several planned drill locations.
AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005