Coal characteristics of major coal-bearing sequences, Gallup Field, northwestern New Mexico
— Gretchen Hoffman Roybal

The New Mexico Bureau of Mines and Mineral Resources (NMBM&MR) has collected coal resource and coal quality data fur the National Coal Resource Data System (NCRDS) and recently was the lead agency for a state-funded drilling project designed specifically to obtain coal samples for analysis The stratigraphic and quality data collected from these projects provide a sufficient data base to begin examination of the coal characteristics of the two major coal-bearing sequences in the Gallup coal field.

 

The Gallup field is of economic importance because of the coral resources in the Dilco Coal Member of the Crevasse Canyon Formation, and the undifferentiated Gibson Coal Member of the Crevasse Canyon and Cleary Coal Member of the Menefee Formation Both coal-bearing sequences developed just shoreward of two major reversals in shoreline movement, when nearly stationary conditions existed. Consequently, the transitional deposits of the Dilco and Gibson-Cleary coal-bearing sequences contain multiple, stacked and often thick coal seams. This contrasts with coal deposition during active shoreline migration when coals arc thinner and seaweed throughout the section. The characteristics of the Gallup-held coals appear to he indicative of their position relative to the shoreline at the time of deposition.