Influence of
Mass Transport Deposit on Stratigraphic Evolution,
Channel Morphology, and Turbidite Reservoir
Preservation and
Bakare, Olusola1,
Neil Hurley2, Timothy McHargue3, Piret
Plink-Bjorklund4 (1) Chevron International Exploration and
Production, Lagos, Nigeria (2) Colorado School of Mines, Golden, CO (3)
Chevron, San Ramon, CA (4) Colorado School of Mines, Golden,
Mass transport deposits (MTDs) represent a major component of the
Miocene-Pleistocene deep-water system, offshore
The dataset used for this study is a
conventional 3D seismic survey and a version of coherency volume. Although
there are several wells in the area, there are no logs or cores in the study
interval.
The deposition of a thick MTD along the
depositional axis of an older channel had a significant effect on the
depositional setting of the basin, which included a change in channel
morphology, a change in depositional axes, and erosional
truncation of turbidite reservoir facies
within confined channels.
Depositional units in the study area have
characteristic stacking patterns. MTDs occur at the
base, overlain by distributary lobe complexes (DLCs), amalgamated channel complexes (ACCs),
and they are capped by drape complexes (DCs). MTDs are very erosive, and they truncate part or all of the
underlying reservoir facies. This study clearly shows
that MTDs could act both as lateral and vertical
seals for turbidite channel reservoirs.
Channel morphology changed from highly
sinuous in the oldest sequence to relatively straight in the youngest sequence,
caused by the deposition of laterally extensive, thick MTDs
over older channel deposits. There is also a variation in the architectural
pattern of turbidite reservoir deposits between older
and younger channels separated by MTD deposition.
AAPG Search and Discover Article #90063©2007 AAPG Annual Convention, Long Beach, California