ABSTRACT: The Da Nang Carbonate Fairway--Constraining Exploration Risk in a Frontier Area

DICKENS, JEFFREY S., and DAVID C. HOLLAND, BP Exploration, Uxbridge, Middlesex, United Kingdom

This paper demonstrates the use of exploration techniques, normally associated with relatively mature, data-rich areas, in attempting to identify and quantify critical risk factors in a frontier environment. A case study of the Da Nang carbonate fairway, offshore Vietnam, forms the vehicle for this demonstration.

The Da Nang carbonate fairway is defined by a largely middle Miocene aged carbonate platform reservoir, sealed by a drowning event and overlying distal deep water clastics. Adjacent and underlying areas of syn-rift section and laterally equivalent basinal mudstones provide a number of potential source rock environments. Studies were undertaken prior to drilling to address the interpreted critical factors; presence of an adequate source, timing of charge and effective seal, migration effectiveness, and reservoir quality.

Geochemical modeling indicates which combinations of heat-flow and stratigraphic position for the source rock are likely to lead to success, and allows estimates of the source properties required for significant trapped volumes. Relative acoustic impedance studies allow the recognition of areas of relatively higher porosity. These results were used to assist selection of well locations.

Drilling results have confirmed the general validity of the techniques applied. The pre-drill model has proved to be very robust. Careful application of modern technology and techniques, normally requiring well control, has been successfully used to constrain the geological model and significantly influence operational decisions.

AAPG Search and Discovery Article #91015©1992 AAPG International Conference, Sydney, N.S.W., Australia, August 2-5, 1992 (2009)