Deepwater Turbidite Reservoir Characterization and Geological Modeling of the Shwe and Shwe Phyu Gas Discoveries Offshore Northwestern Myanmar

Dongil (David) Kim, Su-Yeong Yang, and Heungbum Yi
Daewoo International Corporation, Yangon, Myanmar/Burma

The Shwe and Shwe Phyu gas discoveries, found in 2003 and 2004 respectively, are located offshore northwestern Myanmar. The two gas discoveries cover approximately 200 Km² in water ranging from 80 to 150 meters deep. The gas reservoirs are Late Pliocene turbidite sandstones deposited between 2,900 and 3,300 meters sub-sea with net sand thickness up to 75 meters.
A detailed reservoir characterization study has provided geological models required for resource estimation and optimum input to the field development plan and the reservoir simulation. A variety of geological scenarios have been modeled together with detailed subsurface reservoir analyses. Considering reservoir uncertainties, low, best and high cases of each parameter were used as input for the geological models resulting in resources estimates of the three different cases.
There are two distinctive types of reservoir in the Shwe and Shwe Phyu discoveries: one with thinly bedded sand deposited in a levee and overbank system, and the other with massive sand deposited in a lobe system. A total of six petrofacies were generated based on well log interpretation using a sand-silt-clay model, and then calibrated with core lithofacies. These petrofacies allow a reasonable determination of the sedimentary environments. High-quality 3D seismic data with seismic attributes were used to define architectural elements of various reservoirs. The six petrofacies were used as input for facies modeling and populated into these architectural elements. The petrofacies play an important role in characterizing the porosity profile, establishing a relationship between porosity and permeability, and defining the saturation height function to populate petrophysical properties into the Shwe and Shwe Phyu geological models.

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