Integrated Prospect Evaluation Using Electromagnetic, Seismic
, Petrophysical, Basin Modeling, and Reservoir Engineering
Data
Elizabeth Lorenzetti Harvey, Odd-Petter Skogly, Tracy Burke, and Luiz Amado
Shell International Exploration and Production Inc, Houston, TX
A deepwater prospect in the Campos Basin, Brazil, was evaluated using a combination of geophysical and geological technologies including controlled-source electromagnetic data
,
seismic
amplitude-vs.-offset and inversion
data
, basin- and prospect-scale modeling of hydrocarbon generation and migration, and petrophysical input to reservoir engineering models. The integration of these disciplines produced a consistent story for the prospect that reduced the uncertainty of the
interpretation
. Key uncertainties were the presence of reservoir and the presence, quality, and producibility of hydrocarbons. Many of the analyses, considered alone, were inconclusive or highly uncertain. Combining the analyses increased confidence in the
interpretation
, and several scenarios were dropped. For example,
seismic
forward modeling results using petrophysical trend
data
were ambiguous regarding the presence of reservoir and hydrocarbons. Reservoir engineering and offset well
data
suggested a likelihood of heavy oil with a
seismic
response similar to brine.
Seismic
AVO analysis indicated a weak response at the crest of the structure.
Seismic
inversion results supported the presence of reservoir, but indicated a wet response in all but the most crestal areas of the prospect. Prospect-specific basin modeling indicated that hydrocarbon migration into the prospect was unlikely, although an oil discovery was located only a few kilometers away. Electromagnetic
data
were acquired over the prospect and showed a negative response. This result was used to downgrade scenarios that could not be discounted with other
data
types. The integration of these
data
and methods has served to downgrade a prospect that has been in the exploration portfolio inventory for five years.