Episodic growth of a Waulsortian buildup: The Lower Carboniferous Muleshoe Mound, Sacramento Mountains, New Mexico, USA

Muleshoe Mound is a composite Waulsortian buildup that crops out along the western escarpment of the Sacramento Mountains, New Mexico. Exceptional exposures of Muleshoe Mound have enabled a detailed stratigraphic model to be developed, subdividing the buildup into five separate stratal units. Each stratal unit differs in facies, geometry and symmetry reflecting changes in the character and intensity of different environmental conditions (energy, carbonate production, oxygenation and accommodation space). Hiatal surfaces mark periods of mound crisis and/or sea-level fluctuations. These hiatal surfaces highlight the episodic nature of the mound's growth. Episodic growth acted as an important control on this buildup's development, facies and early diagenesis. Features and patterns of the Muleshoe Mound conflict with the traditional interpretation of the Waulsortian as quiet, stable, deep-water buildups. Muleshoe Mound appears to have grown in appreciable currents where accommodation space was a crucial control on growth.