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Ultra high-resolution (UHR) marine seismic is a scaled-down version of conventional seismic acquisition. Source-receiver separation and depth, shooting rate and seismic wavelengths are typically ten times smaller than for conventional seismic operations. Under ideal conditions, ten times higher subsurface resolution may be achieved, but there will also be less depth penetration due to anelastic damping of the high-frequency seismic waves.

In this study on the Mowry and Muddy interval in the Powder River Basin, we have evaluated a number of the controlling factors on productivity and identified those regions with greater prospectivity across the basin. We have combined classic geological disciplines with robust geophysical analysis to deliver an integrated geoscience solution.

An integrated, multi-disciplinary approach of correlating core facies to petrophysical wireline facies to seismic facies for tight unconventional sandstones is presented along with the results of a simultaneous, geostatistical seismic inversion. This integrated approach results in an improved understanding of the spatial distribution, geometry, and internal architecture of reservoir characteristics.

Time-lapse seismic surveys are intended to measure changes in the subsurface related to reservoir production. Accurately estimation of the reservoir-level requires prior corrections to layers above the reservoir, including the water layer. Water layer changes can be attributed to ocean tides and water velocity changes, which require offset- and depth-dependent timing corrections. These can be difficult to estimate in shallow water marine streamer data sets; thus we developed a completely data-driven method that reduces timing differences and is effective in both shallow and deep water.

As global energy demand continues to rise, continued investment in oil and gas will be critical to keep pace. Recent frontier basin exploration, particularly in deepwater basins in Namibia, Côte d’Ivoire, Guyana and Brazil, have yielded high-impact discoveries. However, these settings demand identification of large prospects to justify high drilling and development costs. In such cases, quantitative interpretation techniques play a critical role in de-risking prospects and reducing exploration risks.

Subsalt imaging is challenging at the Thunder Horse field in the Gulf of Mexico primarily because of the salt canopy overlying roughly 75% of the structure. Since the Thunder Horse discovery, advancements in seismic acquisition techniques and imaging technologies have helped improve subsalt imaging. The latest successful application is from a tilted transverse isotropy (TTI) reverse time migration (RTM) project combining two wide azimuth towed streamer (WATS) data sets and three narrow azimuth towed streamer (NATS) data sets. We present the results from this project to showcase some key contributors to the dramatic structural image improvements with better defined three-way events and a higher signal-to-noise ratio (S/N).

High-quality and well-positioned seismic data are key requirements of the decision-making process to recover the remaining and bypassed hydrocarbons in mature areas. A great deal of seismic exploration has taken place within the Central North Sea, using a variety of acquisition configurations including the latest broadband solutions. Through decades of exploration, most surveys in this mature basin have been reprocessed multiple times as techniques have evolved and, every so often, significant advances in technology warrant the application of these new approaches in a wholesale way. This is what CGG has recently achieved with new seismic acquisition and reprocessing of key multi-client surveys covering the entire Central Graben in the North Sea.

A gas field, China, the target reservoirs are mainly delta front depositions, which are tight, thin, and below the tuning thickness. In order to charaterize the thin effective reservoir and porosity distribution in this field, a geostatistical inversion and co-simulation were performed. Using geostatistical inversion technology we can integrate the information of well logs, geological constraints, geostatistical parameters and seismic data to create multiple high resolution realizations, resulting in highly detailed elastic volumes of P-Impedence, Vp/Vs, density, as well as lithofacies distribution and the co-simulated prosity. The combination analysis of the results can be used to propose new drilling locations. New well data shows the validity of this technology, maximum solve the problem of the low porosity, low permeability and thin reservoir.

In this paper, we described some of the key challenges faced and their solutions during the reservoir characterization study. Shear log prediction can be done quickly by methods, such as multi linear regression and also by building a robust petro-elastic model, if pore geometry and rock moduli are known. Both methods provide comparitive results and helps to rectify inaccurate data or fill missing gap. Rock physics modeling also helps to gain confidence on the quality of petrophysical curve by comparing the difference between original (measured) vs. predicted (modelled) curves. Reservoir and non reservoir rocks can be distinguished on elastic properties cross plots. Some thoughts are shared on the methods to calculate petrophysical input, such as shale volume, porosity, water saturation with field wide approach. Once consistent set of logs are available, further analyses, such as well to seismic tie, AVO and time-lapse study can be accomplished.