Abstract: New Technologies in Imaging and Reservoir-Characterization of Deep-Water Channel and Related Depositional Systems Exploration

Keskes, N.; Morice, M.; Jean Jean, F. - Elf Exploration Production;France; Kolla, V. - Elf Exploration Angola

From auto-tracking of a picked horizon or a "seed" reflection in large 3D volumes of seismic data, and from displays of amplitude several types of coherency, dip and curvature attributes of horizon slices, intervals and proportionally divided sub-intervals, the deep water channel forms are imaged and mapped. These displays reveal diverse deep-water channel systems with varying sinuosities, cutoff meanders, channel migration, avulsion and branching, crevasse-splays and overbanks, and several types of lobeforms. To better understand the internal organization an architecture of the depositional systems, attribute displays are utilized after "peeling" along each reflection or along an internal unconformity surface, and after spectral decomposition of seismic frequencies. The sinuosities, curvature, etc., of meandri channel forms are then measured and the precise morphologies determined. This enables a comparison with the recent deep-sea fan channels. The seismic facies of the deposits constituting the channels and lobeforms and their internal architecture are both qualitatively and quantitatively evaluated utilizing amplitude (maximum, minimum and average amplitude), réflexion-continuity and chaotism etc. displays. In automatic facies recognition, we use a classification tool based on neural network techniques. This detailed facies information is calibrated to well data, when available, and the reservoir heterogeneities are mapped. We present several examples illustrating the above methodologies in detection, imaging, and reservoir characterization of deep-water channel and related depositional systems.

AAPG Search and Discovery Article #90933©1998 ABGP/AAPG International Conference and Exhibition, Rio de Janeiro, Brazil