Solving the Pinda Puzzle: Core is the Key! Pinda Formation, Block 0, Offshore Cabinda, Angola

Sunday K. Shepherd and Bryan Bracken
Chevron Energy Technology Company, San Ramon, CA

The Pinda Formation is a Cretaceous mixed carbonate-clastic system deposited during growth faulting and rafting associated with the opening of the Atlantic. The Pinda rocks range from fully marine, shelfal limestones and mudstones to non-marine fluvial successions, red beds, anhydrites, and every depositional environment in between. Detailed core analyses of over 30,000 feet of core form the basis of the Pinda stratigraphic framework.
A common reservoir characterization workflow integrates the cores, well logs, seismic, and petrophysical data to construct a time and facies constrained stratigraphic model. Steps include: Identifying the depositional facies in core and analyzing the reservoir quality, defining facies sequences and bounding these sequences with sequence stratigraphic surfaces, correlating the well logs to construct a sequence stratigraphic framework, and constructing predictive paleogeographic maps for key stratigraphic intervals.
This workflow is demonstrated using examples from the Minzu Area. The Minzu discovery well penetrated 540 feet of the Pinda Formation with a successful open-hole test. In order to assess the exploration potential in the greater Minzu area, the single Minzu well needed to be tied in to other areas with more well and core control resulting in a consistent stratigraphic framework. The project, with impact exploration and new field development impact, has resulted in an interpretation of the facies in and below the TD of the Minzu well and also tied the Pinda in Block 0 to the Pinda penetration in an adjacent block.

AAPG Search and Discovery Article #90072 © 2007 AAPG and AAPG European Region Conference, Athens, Greece