Mosher, Charles C. (ConocoPhillips) | Keskula, Erik (ConocoPhillips) | Kaplan, Sam T. (ConocoPhillips) | Keys, Robert G. (ConocoPhillips) | Li, Chengbo (ConocoPhillips) | Ata, Elias Z. (ConocoPhillips) | Morley, Larry C. (ConocoPhillips) | Brewer, Joel D. (ConocoPhillips) | Janiszewski, Frank D. (ConocoPhillips) | Eick, Peter M. (ConocoPhillips) | Olson, Robert A. (ConocoPhillips) | Sood, Sanjay (ConocoPhillips)
Summary In late 2011 Woodside Energy Ltd (Woodside), as operator of the proposed Browse LNG Development, acquired the Tridacna 3D Ocean Bottom Cable (OBC) seismic survey (Tridacna survey) over north Scott Reef. The remote offshore location, environmental sensitivity, tidally-emergent reef crests and a semi-diurnal macro-tidal setting imposed significant operational limitations at Scott Reef. The ocean bottom cable technique was selected as the most appropriate technological solution for 3D seismic acquisition in this setting. The survey design incorporated the technical requirements for the acquisition of good-quality seismic data necessary for reservoir imaging whilst cognisant of the operational realities associated with contractor and equipment availability, a shallow restricted marine survey location, complex environmental approval conditions and cost/timing considerations. The survey operations comprised a wide range of activities, operational restrictions and personnel not normally part of conventional offshore towed streamer seismic surveys, and required highly-detailed operational planning.
SUMMARY The ability of the marine controlled source electromagnetic method to resolve anisotropy in the sediment conductivity is not very well understood. In this study, we address the resolvability of anisotropy using a Bayesian approach. Two markedly different methods, slice sampling and reversible jump Markov Chain Monte Carlo have been used for the Bayesian inversion of a synthetic model of a resistive oil reservoir trapped beneath the seabed. We use this to identify which components of data can provide the strongest constraints on anisotropy in the overburden, reservoir and underlying sediments.
Greenhalgh, Jennifer (Petroleum Geo-Services) | Borsato, Ron (Petroleum Geo-Services) | Mathew, Frances (Petroleum Geo-Services) | Duncan-Jones, George (Petroleum Geo-Services) | Primenta, Idima (Sonangol) | da Silva, Jandira Marques (Sonangol) | da Silva, Luis Narciso (Geotec)
Summary The frontier offshore basins of Angola hold tremendous potential for hydrocarbons in the Pre-Salt section. The Angolan basins have similarities with the Pre-Salt of the Brazilian margin which abutted the Angola offshore area prior to opening of the South Atlantic. Traps were formed during rift phases and include horsts and tilted fault blocks. Depth-migrated dual-sensor streamer seismic improves the imaging of syn-rift structures, which now allows the identification and mapping of prospects in underexplored acreage. Analyses of oils from both sides of the Atlantic indicate similar source rocks, and seismic data show analogous structures.