High-Resolution
Correlation of Gulf of Mexico
Pliocene-Pleistocene Sands
G. M. Ragan, W. H. Abbott
Correlating individual sands is critical to field development and reservoir
management. High-resolution
biostratigraphy can provide this correlation.
Bioevents identified in the hemipelagic muds, provide an additional framework
for calibrating seismic record sections. Applying this high-
resolution
data set
can reduce the risk in development drilling.
Regional extinction data, typically separated by hundreds or even thousands
of feet, permit calibration of regional mapping horizons between which reservoir
objectives most often occur. New studies in the Gulf of Mexico
Pliocene-Pleistocene reveal local and semiregional signals between regional
extinctions. These signals, or events, are caused by physical and/or chemical
fluctuations in oceanic water masses through time. Planktonic assemblages
reflect and imprint this signal on the accumulating sediments. Identifying and
documenting these events is the principal behind high-resolution
biostratigraphy. Plotted on electric logs and seismic sections, such signals
allow for refined correlation and subdivision of sediment packages.
From conventional well cuttings, we present high-resolution
biostratigraphic
analyses from two fields in the High Island and Green Canyon areas.
Biostratigraphic events have been identified and local zonations established
through the sand-rich productive intervals of both fields. Individual sands and
sandy intervals are correlated using this technique.
AAPG Search and Discovery Article #91022©1989 AAPG Annual Convention, April 23-26, 1989, San Antonio, Texas.