Keys to Successful Morrow Formation Exploration, Southeastern New Mexico

L. J. Mazzullo¹ and B. S. Brister^2
1Certified Petroleum Geologist, Albuquerque, NM
²New Mexico Bureau of Mines and Mineral Resources, Socorro, NM

The Morrow Formation is the most important gas producer in southeastern New Mexico in terms of volume produced (>3 Tcf) and level of drilling activity. Morrow reservoirs are difficult to economically explore due to the structural, stratigraphic, and diagenetic complexity of individual reservoirs, the difficulty of effectively drilling and completing the wells, and competition for acreage over geologicallytargeted drilling locations. For these reasons, the Morrow play is underdeveloped and will continue to yield significant new discoveries into the future.

The most common Morrow play pitfalls stem from either applying regional concepts that are inappropriate at the prospect scale, or conversely, extrapolating individual field parameters to larger regional plays. Prospects based on regional stratigraphic correlations or large seismic data sets, combined with an incomplete understanding of the geologic risk and economics of the play, often yield frustrating and expensive drilling failures.

Morrow play exploration success relies upon detailed, integrated multidisciplinary investigations of small areas, typically less than 2 townships in size. Numerous single-well and multi-well fields may exist within such areas due to previously unrecognized structural and stratigraphic complexity. Factors such as wet wells, low permeability, and intraformational unconformities may set up new discoveries. The interplay of local tectonics, sequence stratigraphy and sedimentology must be understood and be consistent with well-scale log and sample data. Targeted, small-scale, geologically constrained seismic data can effectively supplement the exploration program. When all these disciplines are combined, the Morrow play can be a more costeffective means of building significant gas reserves.

AAPG Search and Discovery Article #90905©2001 AAPG Southwest Section Meeting, Dallas, Texas