GGI is pleased to announce the publication of Open-File Geologic Map 256, Geologic Map of the Cubero 7.5-Minute Quandrangle, Cibola County, New Mexico, by Colin T. Cikoski, Paul Drakos, and Jim Riesterer.
GGI geologists Paul Drakos and Jim Riesterer completed mapping and compiled field data for the Quaternary geology of the Cubero Quadrangle south of Mount Taylor in west-central New Mexico. GGI’s mapping shows that fan units forming the piedmont south of Mount Taylor are graded to ancestral Rio San Jose stream terraces. GGI completed soil stratigraphic descriptions, which are used to understand depositional processes in alluvial valleys, and relationships between fan units.
The Pliocene and Quaternary deposits and associated geomorphic surfaces in the Mt. Taylor area record a history of long-term incision interrupted by periods of base level stability. In contrast to the overall Plio-Quaternary history, the late Quaternary has been characterized by alternating periods of erosion and deposition. Approximately 200-300 m of incision has occurred into the Pliocene pediment surface between 2.5 m.y. and the present time, likely in response to regional uplift. Periods of erosion and deposition during the late Quaternary are likely in response to climatic fluctuations, continued regional uplift, and/or episodic volcanism in the Zuni Bandera volcanic field periodically blocking drainages (Drakos and Riesterer, 2013).
The primary objective of the STATEMAP program is “…to establish the geologic framework of areas that are vital to the welfare of individual States (USGS).” In New Mexico, the STATEMAP initiative is headed by the New Mexico Bureau of Geology and Mineral Resources (NMBGMR) at New Mexico Institute of Mining and Technology. GGI has been mapping surficial deposits and working cooperatively with Bureau geologists compile the geology of numerous 7.5 minute quadrangles in the Mt. Taylor vicinity since 2008. The geologic quadrangle maps have been compiled into a composite map of the Mount Taylor area, which can be downloaded at https://geoinfo.nmt.edu/publications/openfile/details.cfml?Volume=571. Individual Quadrangle maps may be down loaded from the STATEMAP website.