Geology topics

Research about New Mexico

Source-linked reports with geographic coverage including New Mexico.

At least 253 records · Page 14Linked to original sources

USGS2015

Ungulate exclusion, conifer thinning and mule deer forage in northeastern New Mexico

The southwestern United States has experienced expansion of conifer species ( Juniperus spp. and Pinus ponderosa ) into areas of semi-arid grassland over the past century. The expansion of conifers can limit palatable forage and reduce grass and forb communities. Conifer species are sometimes thinned through hydraulic mulching or selective cutting. We assessed the effects of these treatments on mule deer ( Odocoileus hemionus ) habitat in northeastern New Mexico to determine if conifer thinning improved cover of preferred forage species for mule deer in areas with and without ungulates. We measured plant cover and occurrence of preferred forage species in the summers of 2011 and 2012. An ongoing regional drought probably reduced vegetation response, with preferred forage species and herbaceous cover responding to conifer thinning or ungulate exclusion immediately following treatment, but not the following year. In 2011, areas that received thinning treatments had a higher abundance of preferred forage when compared to sites with no treatment. Grass coverage exhibited an immediate response in 2011, with ungulate exclosures containing 8% more coverage than areas without exclosures. The results suggest that conifer thinning and ungulate exclusion may elicit a positive response, however in the presence of drought; the positive effects are only short-term.

New Mexico↗

USGS2015

Movement patterns and dispersal potential of Pecos bluntnose shiner ( Notropis simus pecosensis ) revealed using otolith microchemistry

Natal origin and dispersal potential of the federally threatened Pecos bluntnose shiner ( Notropis simus pecosensis ) were successfully characterized using otolith microchemistry and swimming performance trials. Strontium isotope ratios ( 87 Sr: 86 Sr) of otoliths within the resident plains killifish ( Fundulus zebrinus ) were successfully used as a surrogate for strontium isotope ratios in water and revealed three isotopically distinct reaches throughout 297 km of the Pecos River, New Mexico, USA. Two different life history movement patterns were revealed in Pecos bluntnose shiner. Eggs and fry were either retained in upper river reaches or passively dispersed downriver followed by upriver movement during the first year of life, with some fish achieving a minimum movement of 56 km. Swimming ability of Pecos bluntnose shiner confirmed upper critical swimming speeds ( U crit ) as high as 43.8 cm·s −1 and 20.6 body lengths·s −1 in 30 days posthatch fish. Strong swimming ability early in life supports our observations of upriver movement using otolith microchemistry and confirms movement patterns that were previously unknown for the species. Understanding patterns of dispersal of this and other small-bodied fishes using otolith microchemistry may help redirect conservation and management efforts for Great Plains fishes.

New Mexico↗

USGS2015

Hydrologic data from wells at or in the vicinity of the San Juan coal mine, San Juan County, New Mexico

In 2010, in cooperation with the Mining and Minerals Division (MMD) of the State of New Mexico Energy, Minerals and Natural Resources Department, the U.S. Geological Survey (USGS) initiated a 4-year assessment of hydrologic conditions at the San Juan coal mine (SJCM), located about 14 miles west-northwest of the city of Farmington, San Juan County, New Mexico. The mine produces coal for power generation at the adjacent San Juan Generating Station (SJGS) and stores coal-combustion byproducts from the SJGS in mined-out surface-mining pits. The purpose of the hydrologic assessment is to identify groundwater flow paths away from SJCM coal-combustion-byproduct storage sites that might allow metals that may be leached from coal-combustion byproducts to eventually reach wells or streams after regional dewatering ceases and groundwater recovers to predevelopment levels. The hydrologic assessment, undertaken between 2010 and 2013, included compilation of existing data. The purpose of this report is to present data that were acquired and compiled by the USGS for the SJCM hydrologic assessment.

New Mexico↗

USGS2015

U.S. Geological Survey water-resources programs in New Mexico, FY 2015

The U.S. Geological Survey (USGS) has collected hydrologic information in New Mexico since 1889, beginning with the first USGS streamflow-gaging station in the Nation, located on the Rio Grande near Embudo, New Mexico. Water-resources information provided by the USGS is used by many government agencies for issuing flood warnings to protect lives and reduce property damage,managing water rights and interstate water use, protecting water quality and regulating pollution discharges, designing highways and bridges, planning, designing, and operating reservoirs and watersupply facilities, monitoring the availability of groundwater resources and forecasting aquifer response to human and environmental stressors, and prioritizing areas where emergency erosion mitigation or other protective measures may be necessary after a wildfire. For more than 100 years, the Cooperative Water Program has been a highly successful cost-sharing partnership between the USGS and water-resources agencies at the State, local, and tribal levels. It would be difficult to effectively accomplish the mission of the USGS without the contributions of the Cooperative Water Program.

New Mexico↗

USGS2015

Magnetotelluric data collected to characterize aquifers in the San Luis Basin, New Mexico

The U.S. Geological Survey is conducting a series of multidisciplinary studies of the San Luis Basin as part of the Geologic Framework of Rio Grande Basins project. Detailed geologic mapping, high-resolution airborne magnetic surveys, gravity surveys, magnetotelluric surveys, and hydrologic and lithologic data are being used to better understand the aquifers in the San Luis Basin. This report describes one north-south and two east-west regional magnetotelluric sounding profiles, acquired in June of 2010 and July and August of 2011, across the San Luis Basin in northern New Mexico. No interpretation of the data is included.

New Mexico↗

USGS2015

Summary of urban stormwater quality in Albuquerque, New Mexico, 2003-12

Urban stormwater in the Albuquerque metropolitan area was sampled by the U.S. Geological Survey in cooperation with the City of Albuquerque, the Albuquerque Metropolitan Arroyo Flood Control Authority, the New Mexico Department of Transportation, and the University of New Mexico. Stormwater was sampled from a network of monitoring stations from 2003 to 2012 by following regulatory requirements for the National Pollutant Discharge Elimination System stormwater permit. During this period, stormwater was sampled in the Albuquerque metropolitan area at outfalls from nine drainage basins with residential, industrial, commercial, agricultural, and undeveloped land uses. Stormwater samples were analyzed for selected physical and chemical characteristics, nutrients, major ions, metals, organic compounds, and bacteria. General quality of stormwater samples, as measured by dissolved solids, nutrient (with the exception of phosphorus), major ion, and dissolved metal concentrations, was similar to that in samples from the Rio Grande. Of the nearly 200 organic compounds that were analyzed for this study, less than one-third (58 constituents) were positively identified at or above the analytical detection limit in stormwater. Concentrations for volatile organic compounds, semivolatile organic compounds, polychlorinated biphenyls, and pesticides were generally low in the stormwater samples. Fifteen of the 16 polycyclic aromatic hydrocarbons listed on the U.S. Environmental Protection Agency Priority Chemicals list were detected in at least one stormwater sample from each outfall. Maximum concentrations for some polycyclic aromatic hydrocarbons in stormwater did exceed a water-quality criterion. Median concentrations for Escherichia coli ( E. coli ) bacteria in the stormwater samples, including those from the background location (Embudo Arroyo), were above the New Mexico water-quality standard. Concentrations for E. coli in stormwater often exceeded the water-quality criterion. The stormwater quality in Albuquerque was compared with that of six other Western U.S. cities (Phoenix, Arizona; Tucson, Arizona; Las Vegas, Nevada; Denver, Colorado; Salt Lake City, Utah; and Boise, Idaho) for selected constituents. In general, water-quality data for stormwater samples from these six other Western U.S. cities were similar to water-quality data for the stormwater samples from the Albuquerque outfalls. Median concentrations for suspended solids, total phosphorus, and bacteria ( E. coli and fecal coliform) in stormwater samples from the Albuquerque outfalls, as a whole, were higher than those in samples from the other Western U.S. cities except for Las Vegas.

New Mexico↗

USGS2015

Physical characteristics and fish assemblage composition at site and mesohabitat scales over a range of streamflows in the Middle Rio Grande, New Mexico, winter 2011-12, summer 2012

In winter 2011–12 and summer 2012, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, Albuquerque District and the U.S. Fish and Wildlife Service New Mexico Fish and Wildlife Conservation Office in Albuquerque, New Mexico, evaluated the physical characteristics and fish assemblage composition of available mesohabitats over a range of streamflows at 15 sites on the Middle Rio Grande in New Mexico. The fish assemblage of the Middle Rio Grande includes several minnow species adapted to hydrologically variable but seasonably predictable rivers, including the Hybognathus amarus (Rio Grande silvery minnow), a federally listed endangered species. Gaining a better understanding of habitat usage by the Rio Grande silvery minnow was the impetus for studying physical characteristics and fish assemblages in the Middle Rio Grande during different streamflow conditions. Data were collected at all 15 sites during winter 2011–12 (moderate streamflow), and a subset was collected at the 13 most downstream sites in summer 2012 (low streamflow). Sites were grouped into four river reaches separated by diversion dams listed in downstream order (names of the diversion dams are followed by short names of the sites nearest each dam in parentheses, listed in downstream order): (1) Cochiti (Peña Blanca), (2) Angostura (Bernalillo, La Orilla, Barelas, Los Padillas), (3) Isleta (Los Lunas I, Los Lunas II, Abeytas, La Joya, Rio Salado), and (4) San Acacia (Lemitar, Arroyo del Tajo, San Pedro, Bosque del Apache I, and Bosque del Apache II). Stream habitat was mapped in the field by using a geographic information system in conjunction with a Global Positioning System. Fish assemblage composition was determined during both streamflow regimes, and fish were collected by seining in each mesohabitat where physical characteristic data (depth, velocity, dominant substrate type and size, and percent embeddedness) and water-quality properties (temperature, dissolved oxygen, specific conductance, and pH; during summer 2012 only) were measured. Nineteen species of fish were collected among the 15 sites and four reaches over both sampling periods; 10 of these 19 species are introduced. Fish-species richness (total number of fish species collected at each site during each sampling event) among sites that were sampled during both sampling periods ranged from 6 at Rio Salado to 12 at La Orilla. Fish were most abundant at the Lemitar site (1,786 individuals) and least abundant at the San Pedro site (275 individuals). The native Cyprinella lutrensis (red shiner) was the most abundant species collected among all of the sites, accounting for about 42 percent of fish collected. Fish-species richness and catch per unit effort (CPUE) were higher (or equivalent) at all sites during summer 2012 compared to winter 2011–12. The relations between fish assemblage composition (that is, total abundance, which refers to the number of individuals of each species that were collected) and selected environmental variables (physical characteristic data collected at the mesohabitat scale [depth, velocity, and substrate particle size], and mesohabitat types) were explored by using canonical correspondence analysis. Environmental variables explained 8 percent (p=0.48) of the variability in the Middle Rio Grande fish assemblage during winter 2011–12, and Rio Grande silvery minnow were weakly associated with sand substrates, relatively moderate velocities (qualitative descriptors are derived from synthetic gradients extracted from CCAs), and relatively shallow depths. Environmental variables explained 14 percent (p < 0.01) of the variability in the Middle Rio Grande fish assemblage during summer 2012, when Rio Grande silvery minnow were associated with run mesohabitats, relatively high velocities, sand substrates, and relatively moderate depths. The mean fish-species richness was greater in summer 2012 than in winter 2011–12 for each mesohabitat type, and the overall fish-species richness across all mesohabitat types was 0.62 during winter 2011–12, compared to 1.49 during summer 2012. The highest mean CPUE during winter 2011–12 was in isolated pools (54.3 fish per 100 square meters [m 2 ]), whereas the lowest was in flats (18.9 fish per 100 m 2 ). Ranges in CPUE were higher in summer 2012 relative to winter 2011–12 in each mesohabitat type sampled. As in winter 2011–12, the highest mean CPUE during summer 2012 was in isolated pools (233 fish per 100 m 2 ), whereas the lowest was in flats (29.6 fish per 100 m 2 ). Overall mean CPUE per mesohabitat across all mesohabitat types was 29.1 fish per 100 m 2 during winter 2011–12 compared to 85.3 fish per 100 m 2 during summer 2012. Four species of minnows (red shiner, Rio Grande silvery minnow, Pimephales promelas [fathead minnow], and Platygobio gracilis [flathead chub]) were selected to compare preferred mesohabitat characteristics because all are small-bodied minnows and because more than 200 individuals of each of these species were collected. Red shiner were collected across the largest range of depths in both winter 2011–12 (0.02–4.31 feet [ft]) and summer 2012 (0.05–3.4 ft), as well as the largest range of velocities (0.0–4.31 feet per second [ft/s]) during winter 2011–12 among the four minnow species of interest. Rio Grande silvery minnow occurred in the narrowest range of depths (0.30–2.1 ft) during summer 2012, as well as the narrowest range of velocities in both winter 2011–12 (0.0–3.18 ft/s) and summer 2012 (0.02–1.51 ft/s). Water-quality properties were only collected during summer 2012, when low-streamflow conditions existed and water-quality properties were thought to be potentially most limiting to aquatic life. Area-weighted mean water temperatures tended to be higher at the sites that were sampled in August 2012 (25.57 degrees Celsius [°C]) compared to June 2012 (24.61 °C). The highest area-weighted mean water temperature at a given site (29.03 °C) was measured at the Lemitar site on August 7, 2012, coincident with the lowest measured discharge (4.13 cubic feet per second [ft 3 /s]). Area-weighted mean dissolved oxygen concentrations tended to be lower in August (7.46 milligrams per liter [mg/L]) compared to June (8.33 mg/L). The highest area-weighted mean dissolved oxygen concentration (9.13 mg/L) was measured at the Lemitar site on August 7, 2012, and the lowest area-weighted mean dissolved oxygen concentration (6.23 mg/L) was measured at the Los Padillas site on August 10, 2012. Area-weighted specific conductance in the sites upstream from La Joya did not exceed 400 microsiemens per centimeter (μS/cm) at 25 °C, whereas the area-weighted mean specific conductance at La Joya (837 μs/cm at 25 °C), Rio Salado (857 μs/cm at 25 °C), and Lemitar (1,300 μs/cm at 25 °C) were all well above the average of the area-weighted means for the 10 remaining sites (433 μs/cm at 25 °C). Lower area-weighted mean pH values were measured at the 3 sites in and near Albuquerque (La Orilla, Barelas, and Los Padillas—7.98, 8.08, and 7.81, respectively) compared to any of the 10 remaining sites, which had an overall mean pH of 8.44.

New Mexico↗

USGS2015

Assessment of statewide annual streamflow in New Mexico, 1985-2013

In 2014, the New Mexico Water Resources Research Institute began a statewide assessment of the water resources of New Mexico. The U.S. Geological Survey, in cooperation with the New Mexico Water Resources Research Institute, addressed the streamflow component of the assessment by examining streamgage data for major river basins and streams in New Mexico for the study period over water years 1985–2013 (all references to years in this report are to water years). Overall, the total annual inflow to and outflow from New Mexico generally decreased over the study period. The highest annual flows for the Rio Grande occurred in 1985–87, and except at the Rio Grande below Elephant Butte Dam, N. Mex. (08361000), and Rio Grande at El Paso, Texas (08364000), streamgages, the lowest flows occurred in 2002–03. Reaches from the Colorado-New Mexico State line southward to Los Alamos, N. Mex. (reaches RG–1 through RG–4), were all gaining reaches. Based on mean annual streamflow during the study period, reaches from Los Alamos (reach RG–5) southward to El Paso (reach RG–9) were all losing reaches except for the Socorro, N. Mex., reach (reach RG–7). From 1985 to 1995, annual flows in the Red River generally were above the mean annual streamflow, but after 1995, annual flows were more frequently below the mean annual streamflow. The Rio Hondo, Rio Pueblo de Taos, and Jemez River followed similar annual trends as the Red River, but to a lesser extent, over the study period. Over the study period, annual flows in the Rio Chama generally increased downstream, and after 1995, the frequency of above average annual flows decreased, and below average flows became more frequent. The Rio Chama reaches were gaining in most of the years from 1985 to 2013. The Rio Puerco annual flows, at both of the streamgages on this stream, generally decreased after 2000. Reach RP–1 was a gaining reach for 24 years of the study period. In general, Pecos River annual flows decreased substantially from the mean annual streamflow after 2000. The greatest gain on the Pecos River was estimated for the reach below Lake Sumner (reach PEC–5), which had gains in all 29 years of the study, whereas the reach from Lake Avalon southward to Red Bluff Reservoir (reach PEC–9) had losses in all 29 years. The highest flows at all streamgages on the Rio Hondo occurred in 1987; high flows there have generally decreased since 1992. Reaches from Ruidoso to below Two Rivers Reservoir, reaches RH–1 and RH–2, were losing reaches for 16 years and 28 years, respectively, over the study period. The San Juan River for the study period had some of the highest flows of any river in New Mexico, and flow on the river generally increased in the downstream direction. Annual flows at the Animas River streamgages were highly variable but after 1993, generally, tended to decrease. The extended periods of high flows on the Animas River seemed to end in 2000. Over the study period, the reach from the New Mexico border southward to Farmington, N. Mex. (reach ANI–1), generally was a losing reach except for 1987 and 1997. Annual flows at the La Plata River near Farmington, N. Mex. (09367500), streamgage generally were less than the annual inflow to the State at the La Plata River at Colorado–New Mexico State line (09366500) streamgage. Over the study period, the reach from the New Mexico border southward to Farmington (reach PLA–1) generally was a losing reach except for 1986, 1987, and 1993. Prior to 1999, annual flows at Canadian River streamgages varied above and below average, but after 1999, annual flows generally were below average. The Canadian River reaches, below the confluence of the Cimarron River (reach CAN–1) and the Canadian River to Ute Reservoir (reach CAN–2), display that the upstream reach (reach CAN–1) was a gaining reach for all 29 water years but that the downstream reach (reach CAN–2) was a losing reach for all years except 2003. Annual flows for the Cimarron River varied above and below average until 1999 and then generally were below average through 2013. The Cimarron River reach, below Eagle Nest Lake to about halfway to the confluence with the Canadian River (reach CIM–1), generally was a gaining reach except for 1996, 2002, 2011, and 2013. Gila River annual flows varied above and below average until 2005 and thereafter generally were below average. Over the study period, the reach from the Gila River near Gila, N. Mex. (09430500), streamgage to the Gila River below Blue Creek, near Virden, N. Mex. (09432000), streamgage (reach GIL–1) was a gaining reach for all years except 1990 and 2013, while the reach from the Gila River below Blue Creek, near Virden, N. Mex. (09432000), streamgage to the Gila River near Clifton, Ariz. (09442000), streamgage (reach GIL–2) was a losing reach for all years with data except 1999. The San Francisco River annual flows were relatively high compared to other years in the study in 1985, 1991–93, 1995, and 2005 but were near or below average for the rest of the years of the study. Both reaches on the San Francisco River were gaining reaches for all 29 years of the study.

New Mexico↗

USGS2015

In situ densimetric measurements as a surrogate for suspended-sediment concentrations in the Rio Puerco, New Mexico

Surrogate measurements of suspended-sediment concentration (SSC) are increasingly used to provide continuous, high-resolution, and demonstrably accurate data at a reasonable cost. Densimetric data, calculated from the difference between two in situ pressure measurements, exploit variations in real-time streamflow densities to infer SSCs. Unlike other suspendedsediment surrogate technologies based on bulk or digital optics, laser, or hydroacoustics, the accuracy of SSC data estimated using the pressure-difference (also referred to as densimetric) surrogate technology theoretically improves with increasing SCCs. Coupled with streamflow data, continuous suspended-sediment discharges can be calculated using SSC data estimated in real-time using the densimetric technology. The densimetric technology was evaluated at the Rio Puerco in New Mexico, a stream where SSC values regularly range from 10,000-200,000 milligrams per liter (mg/L) and have exceeded 500,000 mg/L. The constant-flow dual-orifice bubbler measures pressure using two precision pressure-transducer sensors at vertically aligned fixed locations in a water column. Water density is calculated from the temperature-compensated differential pressure and SSCs are inferred from the density data. A linear regression model comparing density values to field-measured SSC values yielded an R² of 0.74. Although the application of the densimetric surrogate is likely limited to fluvial systems with SSCs larger than about 10,000 mg/L, based on this and previous studies, the densimetric technology fills a void for monitoring streams with high SSCs.

New Mexico↗

USGS2014

Reduced population variance in strontium isotope values informs domesticated turkey use at Chaco Canyon, New Mexico, USA

Traditionally strontium isotopes (87Sr/86Sr) have been used as a sourcing tool in numerous archaeological artifact classes. The research presented here demonstrates that 87Sr/86Srbioapatite ratios also can be used at a population level to investigate the presence of domesticated animals and methods of management. The proposed methodology combines ecology, isotope geochemistry, and behavioral ecology to assess the presence and nature of turkey (Meleagris gallopavo) domestication. This case study utilizes 87Sr/86Srbioapatite ratios from teeth and bones of archaeological turkey, deer (Odocoileus sp.), lagomorph (Lepus sp. and Sylvilagus sp.), and prairie-dog (Cynomys sp.) from Chaco Canyon, New Mexico, U.S.A. (ca. A.D. 800 – 1250). Wild deer and turkey from the southwestern U.S.A. have much larger home ranges and dispersal behaviors (measured in kilometers) when compared to lagomorphs and prairie dogs (measured in meters). Hunted deer and wild turkey from archaeological contexts at Chaco Canyon are expected to have a higher variance in their 87Sr/86Srbioapatite ratios, when compared to small range taxa (lagomorphs and prairie dogs). Contrary to this expectation, 87Sr/86Srbioapatite values of turkey bones from Chacoan assemblages have a much lower variance than deer and are similar to that of smaller mammals. The sampled turkey values show variability most similar to lagomorphs and prairie dogs, suggesting the turkeys from Chaco Canyon were consuming a uniform diet and/or were constrained within a limited home range, indicating at least proto-domestication. The population approach has wide applicability for evaluating the presence and nature of domestication when combined with paleoecology and behavioral ecology in a variety of animals and environments.

New Mexico↗

USGS2014

Scale-dependent feedbacks between patch size and plant reproduction in desert grassland

Theoretical models suggest that scale-dependent feedbacks between plant reproductive success and plant patch size govern transitions from highly to sparsely vegetated states in drylands, yet there is scant empirical evidence for these mechanisms. Scale-dependent feedback models suggest that an optimal patch size exists for growth and reproduction of plants and that a threshold patch organization exists below which positive feedbacks between vegetation and resources can break down, leading to critical transitions. We examined the relationship between patch size and plant reproduction using an experiment in a Chihuahuan Desert grassland. We tested the hypothesis that reproductive effort and success of a dominant grass ( Bouteloua eriopoda ) would vary predictably with patch size. We found that focal plants in medium-sized patches featured higher rates of grass reproductive success than when plants occupied either large patch interiors or small patches. These patterns support the existence of scale-dependent feedbacks in Chihuahuan Desert grasslands and indicate an optimal patch size for reproductive effort and success in B. eriopoda . We discuss the implications of these results for detecting ecological thresholds in desert grasslands.

New Mexico↗

USGS2014

Processes of arroyo filling in northern New Mexico, USA

We documented arroyo evolution at the tree, trench, and arroyo scales along the lower Rio Puerco and Chaco Wash in northern New Mexico, USA. We excavated 29 buried living woody plants and used burial signatures in their annual rings to date stratigraphy in four trenches across the arroyos. Then, we reconstructed the history of arroyo evolution by combining trench data with arroyo-scale information from aerial imagery, light detection and ranging (LiDAR), longitudinal profiles, and repeat surveys of cross sections. Burial signatures in annual rings of salt cedar and willow dated sedimentary beds greater than 30 cm thick with annual precision. Along both arroyos, incision occurred until the 1930s in association with extreme high flows, and subsequent filling involved vegetation development, channel narrowing, increased sinuosity, and finally vertical aggradation. A strongly depositional sediment transport regime interacted with floodplain shrubs to produce a characteristic narrow, trapezoidal channel. The 55 km study reach along the Rio Puerco demonstrated upstream progression of arroyo widening and filling, but not of arroyo incision, channel narrowing, or floodplain vegetation development. We conclude that the occurrence of upstream progression within large basins like the Rio Puerco makes precise synchrony across basins impossible. Arroyo wall retreat is now mostly limited to locations where meanders impinge on the arroyo wall, forming hairpin bends, for which entry to and exit from the wall are stationary. Average annual sediment storage within the Rio Puerco study reach between 1955 and 2005 was 4.8 × 10 5 t/yr, 16% of the average annual suspended sediment yield, and 24% of the long-term bedrock denudation rate. At this rate, the arroyo would fill in 310 yr.

New Mexico↗

USGS2014

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2013

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when treatment and distribution of surface water from the Rio Grande began. A population increase of about 20 percent in the basin from 1990 to 2000 and a 22-percent increase from 2000 to 2010 resulted in an increased demand for water. An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the basin. This network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly in 1983. Currently (2013), the network consists of 123 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, currently (2013) measures and reports water levels from the 123 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 123 sites through water year 2013.

New Mexico↗

USGS2014

Post-parturition habitat selection by elk calves and adult female elk in New Mexico

Neonatal survival and juvenile recruitment are crucial to maintaining viable elk ( Cervus elaphus ) populations. Neonate survival is known to be influenced by many factors, including bed-site selection. Although neonates select the actual bed-site location, they must do so within the larger calf-rearing area selected by the mother. As calves age, habitat selection should change to meet the changing needs of the growing calf. Our main objectives were to characterize habitat selection at 2 spatial scales and in areas with different predator assemblages in New Mexico. We evaluated bed-site selection by calves and calf-rearing area selection by adult females. We captured 108 elk calves by hand and fitted them with ear tag transmitters in two areas in New Mexico: the Valle Vidal and Blue Range Wolf Recovery Area. In both study areas, we found that concealing cover structure and distance to that cover influenced bed-site selection of young calves (i.e., <2 weeks of age). Older calves (i.e., 3–10 weeks of age) still selected areas in relation to distance to cover, but also preferred areas with higher visibility. At the larger spatial scale of calf-rearing habitat selection by the adult female, concealing cover (e.g., rocks, shrubs, and logs) and other variables important to the hiding calves were still in the most supported models, but selection was also influenced by forage availability and indices of forage quality. Studies that seek to obtain insight into microhabitat selection of ungulate neonates should consider selection by the neonate and selection by the adult female, changes in selection as neonates age, and potential selection differences in areas of differing predation risk. By considering these influences together and at multiple scales, studies can achieve a broader understanding of neonatal ungulate habitat requirements.

New Mexico↗

USGS2014

The Valles Mountain Volcanic Center of New Mexico

The Valles Mountain region lies in northern New Mexico about 30 miles west of Santa Fe, 50 miles north of Albuquerque, and just west of the Rio Grande. The elevation varies from 6,500 feet at the Rio Grande to 1,200 feet on the higher peaks. ©1931. American Geophysical Union. All Rights Reserved.

New Mexico↗

USGS2014

Volcanic history of the Magdalena District, New Mexico

The Magdalena District in central New Mexico comprises the Magdalena Range and Granite Mountain which are block mountains of the Basin Range type. They consist of Carboniferous sedimentary formations on a pre-Cambrian basement and are covered by Tertiary volcanic rocks. Volcanism in the District was preceded by considerable faulting, tilting, and uplifting very probably in early Tertiary time. The initial volcanic extrusion consisted of latite flows and tuffs now resting unconformably on the Granite Mountain fault-block in the northern part of the District. Subsequent extrusions consisted of alternations of andesites, rhyolites, and latites, and have a minimum thickness of approximately 4,000 feet. Graben faulting, probably in compensation for the effusion of the large volumes of lava, followed and some of the major faults were subsequently the sites of the intrusion of monzonitic and granitic stocks. Late lamprophyre and white rhyolite dikes in large numbers intruded the intrusive as well as earlier extrusive and sedimentary rocks.

New Mexico↗

USGS2014

Earth‐tides shown by fluctuations of water‐levels in wells in New Mexico and Iowa

It is quite generally known that ocean‐tides produce fluctuations of the water‐level in wells of the artesian type located close to the seashore by periodically changing the external load on the aquifer [see 1 of “References” at end of paper]. Fluctuations of ground‐water as a result of earth‐tides, however, are not generally known although they were observed and studied in a flooded coal‐mine in Europe [2] as early as 1879, and later 1905 to 1912 in wells in South Africa [3]. The phenomena of earth‐tides first came to the attention of the writer in March, 1938, when studying fluctuations of the water‐level In an artesian well near Carlsbad, New Mexico, recorded on charts of a water‐stage recorder, which had an approximately semidiurnal period. Because of the distance from the ocean, about 500 miles, and the altitude of the water‐bearing formation, about 2700 feet, it appeared that the fluctuations could not be the result of ocean‐tides. Neither did it appear they could be the result of other natural phenomena such as changing air‐pressure or changes in water‐level of a nearby lake and river. There was no pumpage from the aquifer, so the fluctuations of the water could not be caused by pumping. T. M. Cramer, Resident Manager of the United States Potash Company at Carlsbad, New Mexico, suggested that the fluctuations must be the result of some lunar attraction. Further study of the fluctuation was made by Dr. C. V. Theis, of the United States Geological Survey, and the writer, whereby the effect of changing air‐pressure was eliminated by correcting the water‐levels to an assumed constant atmospheric pressure. In this study it was demonstrated after applying the barometric correction that the remaining fluctuations were fairly regular and progressed with the transit of the Moon. It was also demonstrated that the fluctuations were of the greatest amplitude during the period of new Moon. Further work by W. E. Hale, of the United States Geological Survey, and the writer, has shown that the fluctuations were much more regular and of greater amplitude during the periods of new and full Moon than during the first and third quarters. It was, therefore, concluded that they are related to true earth‐tides. A preliminary note was published in the Transactions of the American Geophysical Union for 1938 [4].

New Mexico↗

USGS2014

Depth of active solution by ground‐waters in the Pecos Valley, New Mexico

The Pecos River Drainage‐Basin is underlain by a thick series of Permian rocks consisting largely of limestone, gypsum (or anhydrite), and halite. The beds have a regional eastward or southeastward dip of 40 to 80 feet to the mile and successively younger beds are exposed at the surface from west to east across the Basin (Fig, 1). The beds of the San Andres formation and the Chalk Bluff formation or its equivalents crop out over most of the broad western part of the Basin (Fig. 1). Most of the eastern part of the Basin is immediately underlain by the redbeds was sandstone of the Dockum group, of Triassic age, which, south of Acme, are separated from the Chalk Bluff formation by the Salado and Rustler formations. North of Acme the Dockum group overlaps successively older formations ana northwest of Santa Rosa it rests upon beds in the lower part of the San Andres formation.

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