New Mexico Geological Society Annual Spring Meeting — Abstracts

Waulsortian mounds comprise a distinctive assemblage of carbonate facies organized into a mounded geometry and apparently confined
stratigraphically to the Lower Mississippian (Tournaisian and Lower Visean). The currently accepted model of Waulsortian mound generation entails in situ biohermal buildup in a moderately deep water setting (>100 m). Depositional and deformational features of well-exposed
mounds in the Sacramento Mountains, New Mexico, suggest the mounds are allochthonous and were emplaced by downslope movement and
subsequent onlapping by flanking, resedimented carbonate debris. Downslope movement of sediment . resulted from a combination of gravity
driven sedimentary processes such as translation (glide and slump), debris flow, grain flow, and turbidity current. Characteristics of the
Sacramento mounds that favor the allochthonous model are dominance of resedimented material within the core and flank facies, non-gradational and non-interfingering transition from core to flanking strata, presence of slump folds and clastic injection dikes at the base of some of the mounds, and a complete absence of framework or sediment-binding organisms.