Reservoir Property Prediction from Seismic for Angola Block 14 Deepwater

Andrew Rieth¹, Francesca Fazzari², and Kathleen Mabe^1
1South Africa Business Unit, Chevron, Houston, TX
²Energy Technology Company, Chevron, Houston, TX

The challenge of planning the development of new fields in Angola Block 14 is being aided by the ability to predict reservoir properties directly from seismic data. The rock properties of Block 14’s deepwater Miocene turbidite reservoirs are such that they generally lend themselves to seismic-based reservoir and fluid detection. These properties can be leveraged using inversion, which merges seismic and well data to generate impedance attributes that are converted to Vkaolinite volumes using Principle Component Analysis (PCA) proximity transforms. These Vkaolinite volumes are then input directly into reservoir models for flow simulation and development planning. This ability to extract reservoir information from seismic data allows us to fill in much-needed detail between wells, which is especially important given our sparse pre-development well control and stratigraphically complex turbidite channel systems.
This workflow is comprised of:
- seismic and petrophysical processing
- QC of data inputs
- rock property analysis
- elastic impedance or simultaneous inversion
- proximity transform of inversion products to Vkaolinite using PCA/SeisWell

These 3D seismic methods are being successfully employed to populate rock properties into reservoir models used in development planning for the Negage, Lianzi, Gabela and Lucapa fields. Vkaolinite or volume of clay generated from PCA/SeisWell is used to define net to gross, porosity, permeability, and saturations to calculate oil in place. These seismic techniques are used to define a range of reservoir connectivity to determine probabilistic recoveries for deepwater developments in Angola Block 14. 3D visualization techniques are used to optimize well placement and define the reservoir basis of design for each field development.

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