Geology topics

Research about New Mexico

Source-linked reports with geographic coverage including New Mexico.

At least 163 records · Page 9Linked to original sources

USGS2020

Simulated increases in fire activity reinforce shrub conversion in a southwestern US forest

Fire exclusion in historically frequent-fire forests of the southwestern United States has altered forest structure and increased the probability of high-severity fire. Warmer and drier conditions, coupled with dispersal distance limitations, are impeding tree seedling establishment and survival following high-severity fire. High-severity patches are commonly dominated by non-forest vegetation, a state that can be reinforced by subsequent fire events. We sought to determine the influence of fire probability on post-fire vegetation development in a severely burned landscape in New Mexico, USA. We used LANDIS-II to simulate three fire probability scenarios—historical fire probability, contemporary fire probability, and the mean of the two—with contemporary climate. As fire probability increased, the mean size of the largest fires and the mean landscape fire severity increased. These changes in fire characteristics resulted in decreased total aboveground biomass and photosynthetic capacity on the landscape after 50 years. Additionally, the distribution of individual species biomass shifted, with early successional species, especially those that resprout after fire, increasing as a fraction of total biomass with increasing fire occurrence. Counter to empirical data, our simulations did not show a conifer establishment limitation, suggesting a source of uncertainty that will need to be addressed to improve projections of forest dynamics under future climate. Even without limited conifer regeneration, continued increases in fire frequency are likely to favor resprouting species and result in a loss of forest biomass and ecosystem productivity in this southwestern forest landscape.

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USGS2020

Geologic map of Petroglyph National Monument and vicinity, Bernalillo County, New Mexico

This geologic map depicts and briefly describes geologic units underlying Petroglyph National Monument and immediately adjacent areas in Bernalillo County, New Mexico. The Monument is underlain dominantly by Quaternary basalts of the Albuquerque Volcanoes volcanic field, a series of basin-filling volcanic flows and associated vents from a monogenetic volcanic highland along the eastern margin of the Llano de Albuquerque. This compilation builds on data of previously published geologic maps and reports but includes new interpretive synthesis of volcanic stratigraphy and a unified representation of Quaternary surficial deposits overlying volcanic deposits within the Monument and areas immediately adjacent. This geologic map emphasizes the distribution of Quaternary volcanic vent areas and lava flow deposits which were incompletely mapped on previous publications. Surficial deposits are simplified, but uniformly mapped and described in contrast to varying map unit distributions, names and descriptions presented in the references above. Underlying deposits of the upper Santa Fe Group are exposed in the western part of the map area and described briefly. North-trending, syn- and post-eruption faulting is well preserved in the volcanic field and reflected in the subsurface models of aeromagnetic data. These faults are dominated by dip-slip displacement and are interpreted as extensional faults of the central Albuquerque Basin of the northern Rio Grande rift. Elongate distribution of vents for most of the volcanic deposits are spatially associated with the easternmost of these faults and are interpreted to reflect eruptions from fissures paralleling the regional extensional fault trends of the rift.

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USGS2020

Optimization assessment of a groundwater-level observation network in the Middle Rio Grande Basin, New Mexico

The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority (ABCWUA), measures groundwater levels continuously (hourly) and discretely (semiannually and annually) at a network of wells and piezometers (hereafter called the observation network) within the Middle Rio Grande Basin in central New Mexico. Groundwater levels that are measured in this observation network provide a long-term hydrologic dataset that is heavily relied upon to make water management decisions. The desire to upgrade and perform maintenance on this observation network initiated this study, which assesses the spatial and temporal importance of measurements towards optimization of monitoring the observation network to reduce or redirect monitoring costs. This report describes the methods and results of the optimization assessment of this observation network, which included separate spatial and temporal methodologies and an evaluation using principal component analysis (PCA). Results from the spatial optimization assessment can be used to help identify observation network sites that do not significantly affect the generation of winter groundwater-elevation contour maps of the production zone. Results from the temporal optimization assessment and PCA can also be consulted when deciding which sites to remove from the network, especially for sites that are monitored more frequently than annually. Results from the temporal optimization assessment can be used to inform the minimum monitoring frequency at the observation network required to capture the trends shown in higher frequency monitoring. The PCA results distinguish spatially distributed characteristic water-level trends that can inform the management decisions that are made when using the spatial and temporal optimization assessment results. Reducing the temporal frequency or spatial density of monitoring is ultimately a management decision that depends on the amount of data loss or degradation that is deemed acceptable while still meeting the network objectives of the ABCWUA. This study can also serve as a starting point to a data gap analysis of local aquifer characteristics and help guide enhanced observation network design as needs arise or in advance of future water management decisions. The results of the spatial optimization assessment indicate that as many as about 20 specified sites can be removed from the observation network with a relatively small loss in the ability to represent the kriged groundwater-elevation surfaces of the production zone that were generated by using median groundwater elevations for two periods: the 2001 time interval and 2015 time interval. This analysis also demonstrated the importance of wells at the margin of the study area and in areas where there are large hydrologic gradients. At many of the 47 hourly monitored sites analyzed in the temporal optimization assessment, temporal trends were well represented for at least one of the reduced monitoring frequencies tested, indicating that a reduced frequency may be sufficient to adequately characterize seasonal and long-term trends. PCA and k-means clustering analysis of the 15 hourly monitored sites that are screened within the production zone indicate that the sites can be categorized into four groups, or clusters, of differing groundwater-level hydrograph characteristics. Except for one cluster, all of the clusters have the potential to be well represented by fewer index monitoring sites.

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USGS2020

Assessment of soil and water resources in the Organ Mountains-Desert Peaks National Monument, New Mexico

The Organ Mountains-Desert Peaks National Monument (Monument) in southern New Mexico was established in 2014. Given anticipated future demands in the Monument for recreation, livestock grazing, and maintenance of rights-of-way (for example, pipelines and powerlines), the Bureau of Land Management (BLM) needs a better understanding of the current soil and water resources and how infrastructure improvements could affect these resources and the watershed. Specifically, the BLM is concerned with infiltration and erosion and their relations to existing or planned infrastructure, such as roads, campgrounds, location of livestock grazing, and rights-of-way. Alternatives to the current land-use conditions, land-management practices, and infrastructure will be assessed by BLM to best protect Monument resources. The U.S. Geological Survey, in cooperation with the BLM, conducted a study to assess the soil and water resources within the Monument to provide an inventory and compilation of natural-resource information needed by resource managers for the BLM’s land-use planning process for this new national monument. The overall objectives of this study were to (1) compile and interpret existing soil- and water-resource data for the Monument and (2) provide a basic assessment of the surface hydrological effects of selected alternatives to current land use and infrastructure. Data were compiled by using geographic information system software and evaluated for hydrologic and landscape properties that influence infiltration, runoff, and erosion. The effects of changing vegetation were simulated by using different scenarios in the Rangeland Hydrology and Erosion Model. Results of this model indicate areas where soil loss or runoff may occur.

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USGS2020

Mule deer habitat selection following vegetation thinning treatments in New Mexico

Mule deer ( Odocoileus hemionus ) survival and population growth in north-central New Mexico, USA, was previously reported to be limited by nutritional constraints due to poor forage conditions in degraded habitats. Management recommendations suggested thinning of pinyon–juniper to improve habitat quality for mule deer. To evaluate the influence of these vegetation treatments, we monitored habitat selection by 48 adult female mule deer from 2011 to 2013 in a population previously reported to be nutritionally limited. Monitoring occurred 1–4 years after completion of treatments that were intended to improve forage conditions, including mechanical reduction of pinyon pine ( Pinus edulis ) and juniper ( Juniperus spp.) density and senescent brush ( Quercus gambelii–Cercocarpus montanus ) cover. During the summer season, deer selected recently treated areas, but odds ratios decreased with treatment age. However, during winter, deer avoided more recently treated areas and selected thinned areas >4 years old. Deer selected mixed oak ( Quercus spp.) and pinyon–juniper savanna vegetation cover types with a moderately open canopy and ponderosa pine ( Pinus ponderosa ) forests while avoiding grasslands and montane shrublands across all seasons. Deer selected areas closer to water and developed areas, northeast aspects, on gentle slopes, and at lower elevations. Creating a savanna-like cover type may elicit a positive deer response as a result of their strong avoidance of dense, closed canopy pinyon–juniper woodlands. © 2020 The Wildlife Society.

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USGS2020

Investigation of bed and den site selection by American black bears (Ursus americanus) in a landscape impacted by forest restoration treatments and wildfires

The combined effects of long-term fire suppression, logging, and overgrazing have negatively impacted many southwestern U.S. forests, resulting in decreased habitat quality for wildlife, and more frequent and severe wildfires. In response, land management agencies are implementing large-scale forest restoration treatments, but data on how wildlife respond to restoration treatments and wildfires are often limited. We investigated bed and den site selection of American black bears ( Ursus americanus ) using GPS location data and a use/available study design to assess the influence of habitat characteristics, including wildfires, prescribed burns, and thinning treatments on bed and den site selection in the Jemez Mountains, New Mexico. The most supported models suggested that black bears were more likely to select bed sites with a combination of low horizontal visibility ( β = −0.007, SE = 0.002; P = 0.002) and high stand basal area ( β = 0.013, SE = 0.005; P = 0.004). The highest-ranking model for den site selection indicated that black bears were more likely to select den sites with low horizontal visibility ( β = −0.0102, SE = 0.004; P = 0.006). Black bears used all disturbed sites to varying degrees (45% of study area), although 48% of bed sites were located in undisturbed habitat (55% of study area) while only 11% and 2% of bed sites were located in thinned and prescribed burn sites, respectively. Thirty-nine percent of bed sites were located in previous wildfire locations; however, 67% of these sites were in areas with low burn severity. Thirty-eight percent of den sites were located in previously disturbed habitat, 8 of these sites were burned by wildfires. In order to develop effective management plans for black bears, it is essential to understand responses to landscape-scale habitat disturbances due to wildfires and restoration activities, all of which are becoming more prevalent and widespread across southwestern forests. Accounting for the timing, size, and proximity of future restoration efforts would aid in mitigating potential short-term negative effects on black bears.

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USGS2020

Geochronologic and Hf-isotope framework of Proterozoic rocks from central New Mexico, USA: Formation of the Mazatzal crustal province in an extended continental margin arc

The growth of southern Laurentia has been attributed to the accretion of juvenile arc terranes during the successive 1.74-1.68 Ga Yavapai and 1.65-1.60 Ga Mazatzal orogenies. However, in light of the increasing importance of the ca. 1.49-1.40 Ga Mesoproterozoic Picuris orogeny, the tectonic setting in which the Mazatzal crustal province and its distinctive quartzite-rhyolite successions were generated needs additional examination. The Sandia-Manzano-Los Pinos uplift in central New Mexico is an ideal place to characterize the tectonic history of the Mazatzal crustal province. A comprehensive geochronologic and Hf-isotopic dataset for Proterozoic rocks of the Sandia-Manzano-Los Pinos uplift is presented. Plutonic and metavolcanic rocks in the Sandia-Manzano-Los Pinos uplift were emplaced in three pulses at 1668-1655 Ma, 1587 Ma, and 1459-1453 Ma. Hf-isotope data from the Paleoproterozoic plutonic rocks are juvenile, with both leucogranite and arc-related granodiorite yielding εHf(t) values ranging from +6 to +12, compared to the coeval depleted mantle value of +10 at ca. 1.65 Ga. Inherited zircon in Paleoproterozoic rocks suggest that crust older than 1.7 Ga was involved in their genesis. Hf-isotope data from Mesoproterozoic plutonic rocks in the Sandia-Manzano-Los Pinos uplift are consistent with derivation from 1.7-1.6 Ga lithosphere. Detrital zircon indicate that metasedimentary rocks of the lower Manzano Group were derived primarily from local sources that have U-Pb-Hf isotope compositions similar to the plutonic rocks which intrude and volcanic rocks that underlie the Manzano Group. The detrital zircon provenance of the Manzano Group broadens up-section from unimodal populations with age peaks at ca. 1.65 Ga to include 1.7-3.0 Ga detrital zircon derived from older Laurentian sources like the Yavapai and Mojave provinces. We offer a new model for the formation of the Mazatzal crustal province of New Mexico as a continental margin arc built on top of the previously assembled Yavapai province. The Manzano Group quartzite-rhyolite succession was formed by lithospheric extension above a north-dipping, southward retreating subduction zone. The Manzano Group was then subjected to ca. 1.65 Ga syn-magmatic tectonism and later intracratonic contractional tectonism, likely during the 1.46-1.40 Ga Picuris orogeny.

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USGS2019

Controls on debris‐flow initiation on burned and unburned hillslopes during an exceptional rainstorm in southern New Mexico, USA

AbstractUsing observations from 688 debris flows, we analyse the hydrologic and landscape characteristics that influenced debris‐flow initiation mechanisms and locations in a watershed that had been partially burned by the 2012 Whitewater‐Baldy Complex Fire in the Gila Mountains, southern New Mexico. Debris flows can initiate due to different processes. Slopes can fail as discrete landslides and then become fluidized and move downstream as debris flows (landslide initiated) or progressive bulking of sediment from a distributed area can become channelized and concentrated as it moves downslope (runoff generated). In this study, we have an unusual opportunity to investigate both types of debris‐flow initiation mechanisms in our observations of debris flows, triggered by an exceptional rainstorm in the autumn of 2013. Additionally, we compare our observations with those of a dataset of 1138 debris flows in the Colorado Front Range, triggered during the same weather system. We found that runoff‐generated debris flows dominated in burn areas, and runoff required to start these flows could be well characterized by the Shields stress. Landslide‐initiated debris flows were dominant in unburned areas. Debris‐flow densities were tied to total rainfall and precipitation intensities. Like the observations in the Colorado Front Range, debris‐flow initiation locations were found primarily in areas of relatively sparse vegetation on south‐facing slopes between 25 and 40°, and with upslope contributing areas less than 1000 m 2 . In terms of preferential locations for debris‐flow initiations, 2013 vegetation coverage, approximated by Green–Red Vegetation Index metrics, proved to be more influential than the 2012 burn‐severity designation. The uniformity of observations between our study area and those in the Colorado Front Range indicate that the underlying hydrologic and landscape patterns of the debris‐flow initiation locations documented in these studies could be applicable to the wider southwest and Rocky Mountain regions.

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USGS2019

Calibration analysis and noise estimates of WWSSN Station ALQ (Albuquerque, New Mexico)

World‐Wide Standardized Seismograph Network (WWSSN) records contain daily calibration pulses that can be used to retrieve the magnification as well as the response of the instrument for a given day record. We analyze a select number of long‐period vertical (LPZ) records from WWSSN station ALQ (Albuquerque, New Mexico). Although we find that the response of this instrument varies widely throughout time, we show that in most cases, we are able to estimate a pole‐zero response that has a root mean square error of < 10 % "> <10% ⁠ . The variability of responses in historical networks has been reported elsewhere because a large number of adjustments of the galvanometer and seismometer were necessary. Using our derived responses, we estimate noise levels for a number of 1 hr digitized traces. We find that noise levels for the LPZ ALQ records are lower than previously reported, suggesting that these records can resolve smaller amplitude signals than previously suggested. We also find that although care must be taken in the digitization and calibration analysis, we are not limited by noise introduced in the digitization process. Finally, we see that to retrieve the full secondary microseism amplitude, we must use both the LPZ and short‐period components because the LPZ component is limited by system noise at periods less than ∼ 5    s "> ∼5 s ⁠ .

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USGS2019

Anderson Ranch wetlands hydrologic characterization in Taos County, New Mexico

The Anderson Ranch property (study area), located in Taos County, north-central New Mexico, was transferred from Chevron Mining, Inc. (CMI) to the Bureau of Land Management (BLM) as part of a Natural Resource Damage Assessment and Restoration (NRDAR) court-ordered settlement. The study area supports freshwater emergent wetlands and freshwater ponds. The settlement states that CMI will provide the land and a monetary settlement to support the restoration of the wetlands on the property. To best manage the study area, the BLM requires an understanding of potential effects of climate variability and groundwater withdrawals on the wetland function. This study, completed by the U.S. Geological Survey in cooperation with the BLM, provides an initial hydrologic characterization of the study area, which included literature review, collection of groundwater-level and aqueous-chemistry data, completion of a vegetation survey, and preliminary data analysis. The data compiled, collected, and analyzed as part of this study indicate that the wetlands within the study area are groundwater fed and that the water maintaining the wetlands is modern. Surface-water levels in the pond and groundwater levels in the surrounding wetland fluctuate seasonally. The hydraulic gradient in the study area is from northeast to southwest. Evapotranspiration is a main driver of water demand within the study area.

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USGS2019

Characterization and load estimation of polychlorinated biphenyls (PCBs) from selected Rio Grande tributary stormwater channels in the Albuquerque urbanized area, New Mexico, 2017–18

In cooperation with the New Mexico County of Bernalillo, the U.S. Geological Survey characterized potential polychlorinated biphenyl (PCB) concentration and estimated loading into the Rio Grande from watersheds that are under the county’s jurisdiction. Water and sediment samples were collected in 2017–18 from six sites within four stormwater drainage basins in the Albuquerque, New Mexico, urbanized area for the analysis of PCB congeners and other water-quality constituents during dry and wet seasons. Also, the rainfall-runoff model Arid Lands Hydrologic Model (AHYMO) was used to estimate stormwater discharge at the two sample collection sites not affected by pump station operation. Along with the PCB analysis, the discharge data were used to estimate total PCB stormflow event loads for eight events in these urban Rio Grande tributaries. PCBs were detected in 34 of 36 water samples at concentrations as high as 65.8 nanograms per liter and in 12 of 13 sediment samples at concentrations as high as 163,000 nanograms per kilogram dry weight. Six of the 36 water samples exceeded the New Mexico surface-water quality standard for protection of wildlife habitat and aquatic life of 14 nanograms per liter for PCBs. None of the water samples exceeded the U.S. Environmental Protection Agency’s National Pollutant Discharge Elimination System permit level limit of 200 nanograms per liter for PCBs in stormwater systems discharging into the Rio Grande. PCB concentrations in water samples in this study were not linearly related to antecedent precipitation or measured water-quality parameters, but PCB concentrations had a statistically significant positive Kendall’s tau correlation with total suspended solids for water samples and with total organic carbon for sediment samples. The PCB congener profiles indicate that sources to stormwater drainage basins in Bernalillo County originate both from legacy sources, such as Aroclors (for example, in landfills and old building materials), and from current-use sources, such as yellow pigments (for example, in printed materials and packaging in urban litter or refuse). Total PCB stormflow event loads were calculated with average potential minimum and maximum event loads of 0.73 and 4.32 milligrams per storm event, respectively, at the Adobe Acres pump station site and 56.78 and 315.13 milligrams per storm event at the Sanchez Farms inflow at Albuquerque, N. Mex., site.

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USGS2019

Hydrogeologic framework and delineation of transient areas contributing recharge and zones of contribution to selected wells in the upper Santa Fe Group aquifer, southeastern Albuquerque, New Mexico, 1900–2050

The Santa Fe Group aquifer is an important source of water to communities within the Middle Rio Grande Basin, including the Albuquerque-Rio Rancho metropolitan area and Kirtland Air Force Base, New Mexico. In November 1999, Kirtland Air Force Base personnel observed fuel-stained soils at the Bulk Fuels Facility on the base. Subsequent pressure tests identified pipeline leaks. Fuels stored at the Bulk Fuels Facility have included aviation gasoline, jet propellant 4, and jet propellant 8. The fuels migrated about 480 feet down to the water table. Ethylene dibromide, the constituent making up the most extensive part of the plume and a component of leaded aviation gasoline, has formed a plume that, in December 2016, was 400 to 1,300 feet wide, extended about 5,800 feet northeast from the Bulk Fuels Facility, and was about 3,700 feet from the nearest downgradient water-supply well. Prior to widespread development of groundwater resources in southeastern Albuquerque, groundwater near the present-day location of the Bulk Fuels Facility flowed to the southwest. Groundwater began flowing northeast in about 1980 towards a large area of lowered water levels caused by groundwater pumping. In 2013 and 2014 the Albuquerque Bernalillo County Water Utility Authority, the U.S. Air Force, and the U.S. Geological Survey began a cooperative study to characterize the geology and hydrology of the Santa Fe Group aquifer in the vicinity of the ethylene dibromide plume and to develop a local-scale groundwater flow model to delineate areas contributing recharge and zones of contribution to selected water-supply wells. For this study, a previously developed Middle Rio Grande Basin regional groundwater-flow model was updated, and a smaller local-scale model was developed. Advective groundwater-flow paths were delineated and visualized with the MODPATH particle-tracking program. Of 11 wells included in the historical pumping analysis of areas contributing recharge, only wells K-3, K-7, and RC-4 derived a portion of their water from simulated recharge sources within the local-scale model. None of the areas contributing recharge overlap the Bulk Fuels Facility area or the ethylene dibromide plume footprint as delineated using December 2016 ethylene dibromide data. For the historical pumping analysis of zones of contribution, particles for the 11 selected wells generally moved southwest from the north and east boundaries of the local-scale model, moved past their target well, but reversed direction and moved back towards their target well after 1980 when groundwater flow changed to the northeast. Of the 11 wells, only BR-5, RC-5, and VH-2 had 1980–2013 particle pathlines that overlap the December 2016 ethylene dibromide plume footprint, and wells BR-5 and VH-2 have 1980–2013 particle pathlines that overlap the Bulk Fuels Facility area. Particles that were north of the Bulk Fuels Facility when groundwater flow reversed direction would not have the opportunity to interact with the ethylene dibromide plume. Wells BR-5, K-15, and VH-2 did have particles southwest of the Bulk Fuels Facility in 1980. Particles traveling to BR-5 and K-15 passed under or very near the Bulk Fuels Facility area in the 1980–2013 period, but none of the pathlines were shallow enough to interact with ethylene dibromide at the Bulk Fuels Facility. A few particles traveling to VH-2 passed through the Bulk Fuels Facility area at shallow enough depths to interact with ethylene dibromide at the Bulk Fuels Facility in the 1980–2013 period. Ethylene dibromide has not been detected in water samples collected in 2012 through 2015 from the VH-2 well. Of 10 water-supply wells near the ethylene dibromide plume included in the future pumping analysis of areas contributing recharge, only wells K-3, RC-3, and RC-4 had areas contributing recharge within the local-scale model. The areas contributing recharge for wells RC-3 and RC-4 do not overlap the Bulk Fuels Facility area or the December 2016 ethylene dibromide plume footprint, but K-3 derives part of its recharge prior to 1980 and during 1980–2015 from within the area of the December 2016 plume footprint. The analysis of the future pumping scenarios indicated that wells BR-5, K-3, K-16, RC-5, and VH-2 have pathlines for 1980–2015 and wells K-16 and VH-2 have pathlines for 2015–50 that when projected in plan view pass through the December 2016 plume footprint. Of these five wells, only K-3 and RC-5 have pathlines for 1980–2015 that are above an elevation of 4,800 feet and could interact with the ethylene dibromide plume if ethylene dibromide was present when the particles were present.

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USGS2019

Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2018

The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is hydrologically defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift between San Acacia to the south and Cochiti Lake to the north. A 20-percent population increase in the basin from 1990 to 2000 and a 22-percent population increase from 2000 to 2010 resulted in an increased demand for water in areas within the basin. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began treatment and distribution of surface water from the Rio Grande through the San Juan-Chama Drinking Water Project. 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 Albuquerque Basin. In 1983, this network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. As of 2018, the network consisted of 120 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 ABCWUA, the New Mexico Office of the State Engineer, and Bernalillo County, measures water levels from the 120 wells and piezometers in the network; this report, prepared in cooperation with the ABCWUA, presents water-level data collected by USGS personnel at those 120 sites through water year 2018 (October 1, 2017, through September 30, 2018). Water levels that were collected from wells in previous water years were published in previous USGS reports.

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USGS2019

Differentiating anthropogenic and natural sources of uranium by geochemical fingerprinting of groundwater at the Homestake Uranium Mill, Milan, New Mexico, USA

A multiparameter geochemical-isotopic fingerprinting approach was used to differentiate natural and anthropogenic signatures of uranium contamination near the Homestake uranium mill site (Site), near Milan, New Mexico, USA. The Site consists of two tailings piles from milling operations and groundwater contamination from these tailings have been noted. The Site lies within the lower San Mateo Creek Basin with multiple regional sources of U contamination from mining and mill operations and is underlain by a heterogeneous alluvial aquifer, which is underlain by basement rock of the Chinle Group and the lowermost San Andres-Glorieta aquifer. To help decipher signatures, several statistical approaches were used including PCA, NMDS, and cluster analysis. Trilinear piper diagrams indicate two end member water types at the Site, sulfate-Na-K and sulfate-Ca. Natural alluvial aquifer groundwater in this area, relatively unaffected by mining or milling, appears to be more dominated by bicarbonate than sulfate and the deeper San Andres-Glorieta aquifer that has a mixture of sulfate and bicarbonate. Uranium concentrations from the Site fall into three broad categories, less than the drinking water standard of 30 µg/L (n=3), from 30 to 100 µg/L (n=9) and greater than 100 µg/L (n=8). Component loadings in a principal component analysis are highest for uranium isotopes, 228Ra, gross alpha-beta, molybdenum, chloride, uranium, and sodium, which affect the similarities or differences among wells sampled. Results suggest that several alluvial wells upgradient from the Site have anthropogenic fingerprints from regional sources related to upgradient mining. Wells with higher uranium concentrations have uranium activity ratios close to 1, which is indicative of mining or milling signatures. These same wells have elevated radon activities. This information can be used to inform Site managers on the source of water related to uranium at the Site and provide an approach for geochemical fingerprinting.

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USGS2019

Groundwater-level change for the periods 2002–8, 2008–12, and 2008–16 in the Santa Fe Group aquifer system in the Albuquerque area, central New Mexico

The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority (ABCWUA), has developed a series of maps and associated reports, beginning in 2002, that document groundwater levels in the production zone of the Santa Fe Group aquifer system beneath a large area of the City of Albuquerque, New Mexico (hereafter called the study area). Herein, we document the construction of groundwater-level change maps for representative conditions during three periods: 2002–8, 2008–12, and 2008–16. Groundwater-elevation changes correspond to water use by the ABCWUA, with declines occurring prior to 2008 and accelerating recovery after 2008. Prior to 2008, the ABCWUA relied exclusively on groundwater from the Santa Fe Group aquifer system for municipal water supply. For the period 2002–8, near the end of the period of exclusive groundwater use, groundwater elevations in the production zone of the Santa Fe Group aquifer system declined as much as 20 to 30 feet. The largest 2002–8 groundwater-elevation declines were observed near the southeast corner of the study area and to the west of the Rio Grande. Since the ABCWUA implemented the San Juan-Chama Drinking Water Project in 2008, the proportion of municipal water supply sourced directly from surface water has increased to approximately two-thirds of the total water supply in 2016. Following initiation of this change in supply in 2008, groundwater elevations in the production zone of the Santa Fe Group aquifer system cumulatively rose as much as 20 to 30 feet by 2012 and 30 to 40 feet by 2016. The largest groundwater-elevation rises were observed near the northeast and southeast corners of the study area and to the west of the Rio Grande, whereas groundwater-elevation declines since 2008 were restricted to a localized area on the eastern margin of the study area. The area beneath the pre-flood-control-era (1971) flood plain of the Rio Grande underwent the least amount of groundwater-level change during any period, with minimal change prior to 2008 and small groundwater-elevation rises of less than 10 feet since 2008.

New Mexico↗

USGS2019

Effect of hydrologic, geomorphic, and vegetative conditions on avian communities in the Middle Rio Grande of New Mexico

We evaluated relationships among hydrogeomorphology, vegetation structure and composition, and avian communities among three subreaches of the San Acacia Reach of the Middle Rio Grande (MRG) River of New Mexico. The subreaches varied in degradation, with Subreach 1 being severely entrenched and hydrologically disconnected, Subreach 2 being the least impacted, and Subreach 3 being intermediately disturbed. Avian point count and habitat surveys were conducted to determine avian community structure and abundance, geomorphic feature, surface flooding, and vegetation structure and composition. Ground-nesting birds and low shrub-nesting birds were insensitive to hydrogeomorphic changes as they do not rely on native understory but can use exotic understory or woody debris. In contrast, canopy-nesting birds required native overstory; therefore, they were sensitive to hydrogeomorphic changes as native overstory species require surface floods to germinate and establish. Additionally, native overstory did not vary as expected as the moderately impacted subreach, Subreach 3, had more native overstory ( x ¯ "> x¯ = 30.04%, SE = ±4.57) than the least disturbed subreach, Subreach 2 ( x ¯ "> x¯ = 11.20%, SE = ±1.96). These findings were a result of temporal asynchrony between hydrogeomorphic conditions and overstory composition. No subreach is unaltered and all have been affected by the hydrologic and geomorphic changes on the MRG.

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USGS2019

Estimated 2016 groundwater level and drawdown from predevelopment to 2016 in the Santa Fe Group Aquifer System in the Albuquerque Area, Central New Mexico

The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority (ABCWUA), has developed a series of maps and associated reports to document changes in the groundwater level in the production zone of the Santa Fe Group aquifer system in the Albuquerque, New Mexico, area. The current map and associated report document the construction of contours representing the groundwater-level surface of winter (November to March) conditions for water year 2016 and estimated net groundwater-level declines (called drawdown) since widespread groundwater pumping began in the early 1960s (called predevelopment conditions). Prior to 2008, groundwater withdrawal from the Santa Fe Group aquifer system was the principal water supply for the study area. The large quantity of withdrawal relative to recharge resulted in drawdown throughout the Albuquerque area. In response, the ABCWUA implemented a strategy for sustainable development of its water resources, including the diversion of surface water as part of the San Juan-Chama Drinking Water Project in 2008. The 2016 groundwater-level contours indicate that the general direction of groundwater flow is towards clusters of production wells in the eastern and northwestern parts of the study area. Drawdown from predevelopment to 2016 is greatest along the eastern margin of the study area and in the northwestern part of the study area, likely correlated with groundwater withdrawals and potentially compounded by proximity to faults. Comparing drawdown in water year 2016 to that of water years 2002, 2008, and 2012 shows a reduction in drawdown (groundwater-level rebound) in the study area since 2008, which corresponds with the timing of reductions in groundwater withdrawals as a result of the ABCWUA’s San Juan-Chama Drinking Water Project. Time-series analysis of groundwater-level measurements in piezometers within the study area also indicates the recent groundwater-level rebound since 2008.

New Mexico↗

USGS2019

Calibration of Precipitation-Runoff Modeling System (PRMS) to simulate prefire and postfire hydrologic response in the upper Rio Hondo Basin, New Mexico

The Precipitation-Runoff Modeling System (PRMS) is widely used to simulate the effects of climate, topography, land cover, and soils on landscape-level hydrologic responses and streamflow. The U.S. Geological Survey (USGS), in cooperation with the New Mexico Department of Homeland Security and Emergency Management, developed procedures to apply the PRMS model to simulate the effects of fire on hydrologic responses. A PRMS model was built of the upper Rio Hondo Basin from the headwaters to approximately 19 miles downstream from the USGS streamgage Rio Hondo above Chavez Canyon near Hondo, New Mexico, by using 24 hydrologic response units (HRUs), or hydrologically similar subareas, from the National Hydrologic Model. A quasi-graphical user interface was created to easily query and analyze published PRMS sensitivity-analysis data. Simulation of mean daily streamflow was most sensitive to parameters related to snowmelt or infiltration throughout the upper Rio Hondo Basin. In the basin’s eastern and northern HRUs, flashiness and timing of streamflow were most sensitive to interflow; in many western-basin HRUs (higher elevations), flashiness of streamflow was most sensitive to soil moisture parameters, and timing of streamflow was most sensitive to infiltration and evapotranspiration parameters. The PRMS model was calibrated for the fire-affected North Fork Eagle Creek subwatershed by comparing modeled to observed daily streamflow for the nonfrozen (May through October) period for a prefire and postfire time period. The prefire model was calibrated for the period 2007–12 before the 2012 fire, and the postfire model was calibrated for a 2-year (2014–15) period after the fire. Model parameterization combined manual adjustment of 8 parameters on the basis of prior knowledge and automated adjustment of the most sensitive parameters by using the Let Us Calibrate interface. A gridded, daily precipitation dataset that captured the spatial heterogeneity across the study watershed was used as the precipitation input for calibration. Model performance was assessed as satisfactory by using standard statistical measures for prefire and postfire periods. The calibrated model was run by using data from a single precipitation gage to better represent the effect of localized, extreme storms on postfire hydrologic response. The calibrated models for prefire and postfire conditions simulated streamflows with greater consistency than the uncalibrated model for the corresponding (prefire or postfire) period of hydrographic record. The effect of fire on streamflow was found to be primarily a shift from streamflow dominated by base flow prior to fire to streamflow dominated by surface runoff after fire.

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