High-Resolution Reservoir
Characterization of Midcontinent
Sandstones Using Wireline Resistivity Imaging, Boonsville (Bend Conglomerate)
Gas Field, Fort Worth Basin, Texas
David L. Carr, Robert Y. Elphlck, and Laura Stager Foulk
In the absence of abundant core data, Formation MicroScanner (FOOTNOTE *) (FMS) and Fullbore Formation Microlmager (FOOTNOTE *) (FMI) wireline logs from 3 wells in Boonsville Field provided continuous geologic information in a 1000-foot thick, Pennsylvanian (Atoka) interval. Cores provided the most detailed sequence-stratigraphic information, but only 358 ft of core from 4 wells was available to evaluate the 30 mi2 project area. The FMS and FMI logs thus served as continuous, oriented 'virtual cores' that expanded our stratigraphic database and improved our interpretations, which included the identification of key chronostratigraphic surfaces, lithofacies, sedimentary structures, faults, and fractures.
Paleocurrents inferred from the FMS and FMI images suggest that most Bend
Conglomerate sandstones are lowstand valley-fill deposits derived from the
Muenster and Red River Uplifts, rather than Ouachita-derived deltas. Combined
analysis of cores and wireline resistivity imaging technology enabled the
development of a fine-scale, sequence-stratigraphic framework which formed the
basis for correlation and mapping of the major Bend Conglomerate reservoir
zones,
and helped us to identify compartmentalization
mechanisms
within these complex
reservoirs.
FOOTNOTE *. Mark of Schlumberger
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California