Reservoir-Scale
Analysis of Sandstone-Body Dimensions in a Braided Fluvial System, Upper
Williams Fork Formation,
Sommer, Nicholas K.1,
Matthew J. Pranter2, Rex D. Cole3 (1) University of
Colorado at Boulder, Boulder, CO (2) University of Colorado, Boulder, CO (3)
Mesa State College, Grand Junction, CO
This study presents the results of an
outcrop analysis of the Upper Williams Fork Formation (Late Cretaceous) of the Mesaverde Group located in
The Upper Williams Fork Formation in
Fluvial sandstone bodies include single
channels to multiple-story-channel complexes with dimensions ranging from less
than one meter to tens of meters in thickness (or composite thickness) and tens
to hundreds of meters in apparent width. The sheet-like sandstone bodies
typically have apparent width-to-thickness ratios (W:T)
of greater than 30:1. Between-well correlation of individual sandstone bodies
at a reservoir scale is difficult. Amalgamation of sandstone bodies is common
in this high net-to-gross system; however, thin laterally extensive interbedded mudrocks exist that
could compartmentalize sandstone bodies at the reservoir scale.
The sandstone-body dimensional and
descriptive data of the Williams Fork Formation are useful to constrain
reservoir models and aid in predicting the width and lateral continuity of
sandstone bodies between wells when only thickness data are known.
AAPG Search and Discover Article #90063©2007 AAPG Annual Convention, Long Beach, California