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7th Middle East Geosciences Conference and Exhibition
Manama, Bahrain
March 27-29, 2006
Seismic
Coherence Attributes in Mapping the Fracture Network and Improving the
Productivity from Thin, Tight and Fractured Reservoir
1 Petex, Bapco, P.O. Box 25504, Awali, Bahrain, phone: +973 17 753803, fax: +973 17 753322, [email protected]
2 Bapco, Bahrain
This paper describes a case study of utilizing 3D seismic
coherency data to define and mapping fracture network pattern
which was integrated with well testing to improve the productivity from thin, tight and fractured reservoir in the Bahrain field.
The middle Cretaceous Ab zone is a thin, tight ,highly faulted and irregularly fractured limestone reservoir. The difficulty with
this 15 ft, 1 md reservoir has prevented an efficient recovery. The average production of wells is 15 bopd. This has
prompted a detailed integrated study plan to increase the wells' productivity. It is well known that
seismic
coherence data is
a key to define and map the fracture network also well testing is a key to understand the reservoir dynamics. However the
new approach that links transient well testing and production data with fracture network indications derived from
seismic
interpretations has resulted in improving the productivity considerably.
This was accomplished through re-entering old wells and designing special trajectories to intersect productive open
fractures. The productivity was significantly increased to 60 bopd with sustained performance. The paper describes in detail
our approach and methodology to understand the reservoir and its drive mechanism and to increase productivity and
recovery starting from analyzing core data up to designing special configuration wells. The paper further highlights the
pitfalls of the conventional workflow approach in modeling
such difficult reservoirs.