Leo Member of the Minnelusa Formation


The study of the Pennsylvanian Leo Member of the Minnelusa Formation sandstones provides depositional models for use in predicting occurrences of stratigraphic hydrocarbon traps in this challenging region.

Data from Leo outcrops, cores, and wells are compared with data from analogous modern settings to develop a thorough understanding of the depositional processes active during “Leo” time. Using predictive models of regional sandstone sedimentation patterns, six “Leo” oil and gas fields were examined. The study of these fields was undertaken to develop smaller scale rock models that can aid in understanding the distribution of reservoir potential strata.

The study area encompasses 10,908 square miles in Wyoming, South Dakota and Nebraska. Approximately 980 “Leo” wells have analyzed. This study represents several man-years of geological research.

Study Highlights

  • Study Text and Figures
  • 24 Outcrops Measured
  • 29 Cores Described
  • 980 Study Wells
  • 180 Thinsections Examined
  • 6 Field Studies
  • 13 Regional and 14 Field Maps
  • 20 Cross Sections
  • Illustrated Rock Guide

Location Map

Leo Member of the Minnelusa Formation

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