Seismic facies analysis in the Northern Rakhine and implications for predicting reservoir and seal

Abstract

Woodside Energy is one of the largest offshore petroleum acreage holders in Myanmar. Woodside has established a strong acreage position, with interests in nine offshore blocks, covering approximately 56,600km². Extensive 3D seismic data has been acquired in offshore Myanmar, with several well penetrations into the Miocene to Pleistocene stratigraphy. The northerly-derived proto-Bengal Fan feeds the mud/silt-dominated deepwater system. Deposition in the northern Rakhine Basin is controlled by a sediment supply-driven shelf edge that transitions from a progradational (Miocene-Pliocene) to an aggradational (Pliocene-Pleistocene) shelf edge. A diverse range of deep-water depositional elements characterise the proto-Bengal Fan sediment delivery system; including channel, levee, lobes, sediment waves and mass transport deposits. A robust regional depositional model has been defined based on seismic facies analysis and well penetrations, incorporating data from Woodside’s widespread acreage in the northern Rakhine Basin. This presentation will use detailed seismic facies analysis of Woodside’s 3D datasets, and integration of the regional depositional model in the Northern Rakhine Basin, as a predictive tool for defining sealing and reservoir facies. For example, channel-levee complexes are conduits for shelf-derived sediment, and they produce distinct seismic facies such as levees which can act as both seals and reservoirs, while channel and lobe complexes commonly create excellent reservoir facies. Investigations into the evolution of channel-levee complexes that have been defined using seismic facies analysis demonstrate that sedimentary process and syn-depositional paleo-topography are key controlling factors in the distribution of reservoir and sealing facies. Woodside’s position in the Rakhine Basin, an area with proven and potential hydrocarbon volumes, aligns with the company’s strategy to secure international growth opportunities in frontier and emerging basins that leverage Woodside’s experience and capabilities in deep water exploration and development.

AAPG Datapages/Search and Discovery Article #90336 ©2018 AAPG Asia Pacific Region, The 4th AAPG/EAGE/MGS Myanmar Oil and Gas Conference, Myanmar: A Global Oil and Gas Hotspot: Unleashing the Petroleum Systems Potential, Yangon, Myanmar, November 13-15, 2018