The Albuquerque Basin is one of the largest (8,000 km2, 3,060 mi2) and deepest basins (4,407-6,592 m, 14,500-21,600 ft) of the Rio Grande rift. This basin contains the largest metropolitan area in New Mexico. Until 2008, this region relied entirely on groundwater for its water supply. This sole reliance on groundwater resulted from an earlier view that Albuquerque lay on top of the subterranean equivalent of a vast underground lake that would take centuries to exploit. Since the 1960s, the City of Albuquerque had little reason to be concerned about its water supply because wells drilled in the northeast and southeast heights yielded large quantities of potable groundwater. The view of plentiful groundwater was essentially unchallenged until the late 1980s, when water level declines near Coronado Center provoked exploration of the deeper aquifer. Results of the deep aquifer test wells led to reassessment of the regional aquifer and the Middle Rio Grande Basin Project of the late 1990s.
The San Luis Basin is the northernmost and largest basin of the Rio Grande Rift system in New Mexico. Most of the basin is located in Colorado, where it merges to the north with the Upper Arkansas River graben (Grauch and Keller, 2004). The basin is ~150 miles long and 55 miles wide, and has the general form of an east-dipping half graben. Basin-fill material is composed of Tertiary-Quaternary sediments of the Santa Fe Group and late Cenozoic volcanics (Kelley et al., 1976). The basin is bounded to the west by the Tusas and San Juan Mountains and to the east by the Sangre de Cristo Mountains and the Sangre de Cristo fault zone. The deepest part of the basin is found in the Taos graben, a narrow zone 6 to 18 miles wide adjacent to the Sangre de Cristo mountain front (Grauch and Keller, 2004). The southern part of the basin is occupied by the Taos Plateau, which is composed of Pliocene basalt flows that overlie Santa Fe Group basin fill. The southeastern margin of the basin is defined by the Embudo fault zone, which separates the east-tilted San Luis Basin from the west-tilted Española Basin to the south (Bauer and Kelson, 2004).
Northeastern New Mexico is a geologically diverse area that includes the upper Pecos and Canadian river valleys, the eastern margin of the Sangre de Cristo Mountains, and the Raton and Las Vegas Basins, two north-trending assymetric structural basins formed during the late Cretaceous-Paleogene Laramide orogeny. The Raton and Las Vegas Basins are separated by igneous intrusive rocks of the Cimarron Arch, near Cimarron, NM. The gently-dipping eastern margins of these basins are defined by the Sierra Grande Arch and the Raton-Clayton volcanic field (Kelley, 2015; Broadhead, 2015).
The San Agustin Basin is a closed intermontane basin on the northern edge of the Mogollon Plateau, and within the Datil-Mogollon volcanic field of southwestern New Mexico, extending across ~2,400 square miles in Catron and westernmost Socorro Counties. Myers et al. (1994) conducted an investigation of the hydrogeology of the basin, which is summarized here. The San Agustin Basin is bounded to the west and south by the Continental Divide, to the north by the Datil and Gallinas Mountains, and to the east by the San Mateo Mountains. The most recent structural activity in the region was late Tertiary Basin and Range faulting, which formed the San Agustin and Cuchillo Negro grabens. The Plains of San Agustin, which occupy the northeast-trending San Agustin graben, were covered by several large lakes during late Pleistocene time. Playas now occupy these former lake beds. There is no perennial streamflow in the basin.
We began working in Peña Blanca in March 2016 at the request of the NM Environment Department (NMED). The goal was to understand the local hydrogeology of Peña Blanca in order to make a recommendation for an area to place a new well. The need for a new well was highlighted by the discovery of solid waste, a hydraulic fluid tank and a diesel tank immediately adjacent to but on different property than the current municipal well.
The Roswell Artesian Basin occupies over 4,000 square miles in the lower Pecos Valley in Chaves and northern Eddy Counties, and is one of the most intensively farmed regions in the state outside the Rio Grande Valley (Welder, 1983; Land and Newton, 2008). The eastern margin of the basin occurs just east of the Pecos River; the northern boundary is approximately defined by Macho Draw north of Roswell; and the southern end of the basin is located at the Seven Rivers Hills north of Carlsbad. The western margin of the basin is not as well-defined, but is usually located west of Roswell on the Pecos Slope near the Chaves-Lincoln County Line. The basin derives virtually all of its irrigation and drinking water from groundwater stored in a karstic artesian limestone aquifer contained within the Permian San Andres and Grayburg Formations, and from a shallow unconfined aquifer composed of Tertiary-Quaternary alluvial material deposited by the ancestral Pecos River. The Roswell Basin has been described by many workers as a world-class example of a rechargeable artesian aquifer system (e.g., Fiedler and Nye, 1933; Havenor, 1968).
The Estancia Valley is a relatively flat-floored, closed physiographic basin with internal drainage, occupying ~2,000 square miles in central New Mexico. The valley, most of which lies within Torrance County, is bounded to the west by the Manzano Mountains, to the east by the Pedernal Hills, and to the south by Chupadera Mesa. The northern margin of the basin is less well-defined, merging with a high plateau area in southern Santa Fe County (Meinzer, 1911; Smith, 1957; White, 1994). Highest elevations in the Estancia Valley (>9,000 feet) occur along the western rim of the watershed, on the east flank of the Manzano Mountains. Lowest elevations (~5,900 feet) are found along the central topographic axis of the basin, where a north-south trending series of playas formed by deflation are incised into the valley floor (Bachhuber, 1982). Because the Estancia Valley is a topographically-closed basin, the only outlet for precipitation that falls within the basin boundaries is by evapotranspiration, primarily from the playa lakes.
The Palomas Basin is an east-tilted half graben ~35 miles long by 12 miles wide, bordered to the east by the Caballo Mountains and Red Hills, and to the west by the Black Range, Animas Hills, Salado Hills, and southern Sierra Cuchillo. The north end of the Palomas Basin is defined by the Mud Springs Mountains and several faults that intersect near Truth or Consequences, which separate the Palomas Basin from the Engle Basin to the north. The basin merges to the south with the eastern Mimbres Basin (Chapin, 1971). The Palomas Basin contains up to 6,500 feet of Tertiary alluvial fan and lacustrine sediments of the Santa Fe Group along its deep eastern margin, overlain by ~500 feet of alluvial fan and axial-fluvial sediments of the Plio-Pleistocene Palomas Formation (Mack, 2012).
The Arroyo Hondo ground water study reveals a complex, three-dimensional ground water system with multiple hydrostratigraphic units and aquifers. Distribution of the geologic and hydrostratigraphic units is presented through geologic maps and seven detailed cross sections that depict the distribution of geologic and hydrostratigraphic units, well data, surface water features, water levels, faults, and zones of fracturing and sediment layers in volcanic rocks. Cross sections are constructed both parallel and perpendicular to regional ground water flow and illustrate aquifers in the context of the geologic framework, the Rio Grande and the Rio Hondo, local acequias and other surface water features.
