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At least 1,099 records · Page 61Linked to original sources
USGS2012

The effects of wildfire on the peak streamflow magnitude and frequency, Frijoles and Capulin Canyons, Bandelier National Monument, New Mexico

In June of 1977, the La Mesa fire burned 15,270 acres in and around Frijoles Canyon, Bandelier National Monument and the adjacent Santa Fe National Forest, New Mexico. The Dome fire occurred in April of 1996 in Bandelier National Monument, burned 16,516 acres in Capulin Canyon and the surrounding Dome Wilderness area. Both canyons are characterized by extensive archeological artifacts, which could be threatened by increased runoff and accelerated rates of erosion after a wildfire. The U.S. Geological Survey (USGS) in cooperation with the National Park Service monitored the fires' effects on streamflow in both canyons. Copyright 2004 ASCE.

Conference Paper↗
USGS1952

Memorandum on ground-water investigation of four proposed stock wells in Puertocito Area, Socorro County and Canoncito Area, Bernalillo and Valencia Counties, New Mexico

At the request of the Navajo Service, Office ot Indian Affairs, a groundwater iinvestigation of four proposed stock wells in the Puertocito Area, Socorro county and the Canoncito Area., Bernalillo and Valencia counties,New Mexico, was made in November, 1951 (see fig. 1). Although these areas are not on the Navajo Indian Reservation, they were included in the program of study of ground-water resources or the Navajo and Hopi Indian Reservations now being conducted by the Ground Water Branch of the United States Geological Survey. The work was financed by and was in cooperation with the Navajo Service, Office of Indian Affairs.

New Mexico↗
USGS2025

Tracking the sources of metals to the San Juan River, Four Corners Region, USA: An introduction to the thematic issue

Surface water quantity and quality is important for arid and semi-arid regions where many people, including underserved and Indigenous communities, rely on a scarce resource for drinking water, irrigation, livestock and ceremonial uses. The southwestern United States, and specifically the Four Corners Region (Colorado, Arizona, New Mexico and Utah), is an example of this situation. Elevated concentrations of metals including aluminium, arsenic and lead were identified in previous studies and this study in the San Juan River from below the Navajo Dam, through the Navajo Nation to Mexican Hat, Utah. An interdisciplinary team applied approaches and principles of geology, geochemistry, geomorphology, hydrology and statistics to gain a better understanding of the tributaries supplying the source(s) of metals to the San Juan River. This introductory paper provides an overview of the ‘Metal geochemical fingerprinting to identify sub-watershed source contributions to surface water at a regional arid watershed scale, Four Corners Region, USA’ thematic collection . An overview of sampling sites, techniques and potential sources of metals is provided. Approaches used in this study could be applied to investigations in similar systems globally.

Four Corners region↗
USGS2014

Potential postwildfire debris-flow hazards: a prewildfire evaluation for the Sandia and Manzano Mountains and surrounding areas, central New Mexico

Wildfire can drastically increase the probability of debris flows, a potentially hazardous and destructive form of mass wasting, in landscapes that have otherwise been stable throughout recent history. Although there is no way to know the exact location, extent, and severity of wildfire, or the subsequent rainfall intensity and duration before it happens, probabilities of fire and debris-flow occurrence for different locations can be estimated with geospatial analysis and modeling efforts. The purpose of this report is to provide information on which watersheds might constitute the most serious, potential, debris-flow hazards in the event of a large-scale wildfire and subsequent rainfall in the Sandia and Manzano Mountains. Potential probabilities and estimated volumes of postwildfire debris flows in the unburned Sandia and Manzano Mountains and surrounding areas were estimated using empirical debris-flow models developed by the U.S. Geological Survey in combination with fire behavior and burn probability models developed by the U.S. Department of Agriculture Forest Service. The locations of the greatest debris-flow hazards correlate with the areas of steepest slopes and simulated crown-fire behavior. The four subbasins with the highest computed debris-flow probabilities (greater than 98 percent) were all in the Manzano Mountains, two flowing east and two flowing west. Volumes in sixteen subbasins were greater than 50,000 square meters and most of these were in the central Manzanos and the western facing slopes of the Sandias. Five subbasins on the west-facing slopes of the Sandia Mountains, four of which have downstream reaches that lead into the outskirts of the City of Albuquerque, are among subbasins in the 98th percentile of integrated relative debris-flow hazard rankings. The bulk of the remaining subbasins in the 98th percentile of integrated relative debris-flow hazard rankings are located along the highest and steepest slopes of the Manzano Mountains. One of the subbasins is several miles upstream from the community of Tajique and another is several miles upstream from the community of Manzano, both on the eastern slopes of the Manzano Mountains. This prewildfire assessment approach is valuable to resource managers because the analysis of the debris-flow threat is made before a wildfire occurs, which facilitates prewildfire management, planning, and mitigation. In northern New Mexico, widespread watershed restoration efforts are being carried out to safeguard vital watersheds against the threat of catastrophic wildfire. This study was initiated to help select ideal locations for the restoration efforts that could have the best return on investment.

New Mexico↗
USGS2000

Geothermal hydrology of Valles Caldera and the southwestern Jemez Mountains, New Mexico

The Jemez Mountains in north-central New Mexico are volcanic in origin and have a large central caldera known as Valles Caldera. The mountains contain the Valles geothermal system, which was investigated during 1970-82 as a source of geothermal energy. This report describes the geothermal hydrology of the Jemez Mountains and presents results of an earlier 1972-75 U.S. Geological Survey study of the area in light of more recent information. Several distinct types of thermal and nonthermal ground water are recognized in the Jemez Mountains. Two types of near-surface thermal water are in the caldera: thermal meteoric water and acid sulfate water. The principal reservoir of geothermal fluids is at depth under the central and western parts of the caldera. Nonthermal ground water in Valles Caldera occurs in diverse perched aquifers and deeper valley-fill aquifers. The geothermal reservoir is recharged by meteorically derived water that moves downward from the aquifers in the caldera fill to depths of 6,500 feet or more and at temperatures reaching about 330 degrees Celsius. The heated geothermal water rises convectively to depths of 2,000 feet or less and mixes with other ground water as it flows away from the geothermal reservoir. A vapor zone containing steam, carbon dioxide, and other gases exists above parts of the liquid-dominated geothermal zone. Two subsystems are generally recognized within the larger geothermal system: the Redondo Creek subsystem and the Sulphur Creek subsystem. The permeability in the Redondo Creek subsystem is controlled by stratigraphy and fault-related structures. Most of the permeability is in the high-angle, normal faults and associated fractures that form the Redondo Creek Graben. Faults and related fractures control the flow of thermal fluids in the subsystem, which is bounded by high-angle faults. The Redondo Creek subsystem has been more extensively studied than other parts of the system. The Sulphur Springs subsystem is not as well defined. The upper vapor-dominated zone in the Sulphur Creek subsystem is separated from the liquid-dominated zone by about 800 feet of sealed caldera-fill rock. Acid springs occur at the top of the vapor zone in the Sulphur Springs area. Some more highly permeable zones within the geothermal reservoir are interconnected, but the lack of interference effects among some wells during production tests suggests effective hydraulic separation along some subsystem boundaries. Chemical and thermal evidence suggests that the Sulphur Springs subsystem may be isolated from the Redondo Creek subsystem and each may have its own zone of upflow and lateral outflow. The area of the entire geothermal reservoir is estimated to be about 12 to 15 square miles; its western limit generally is thought to be at the ring-fracture zone of the caldera. The top of the reservoir is generally considered to be the bottom of a small- permeability 'caprock' that is about 2,000 to 3,000 feet below land surface. Estimated thicknesses to the bottom of the reservoir range from 2,000 to 6,000 feet. Reservoir temperatures measured in exploration wells range from 225 degrees Celsius just below the caprock to about 330 degrees Celsius in deeper drill holes. Pressures measured in exploration wells in the Redondo Creek area ranged from 450 to 1,850 pounds per square inch. Steam-producing zones have been encountered above the liquid- dominated zones in wells, but the extent of steam zones is not well defined. The reservoir contains a near-neutral, chloride-type water containing about 7,000 milligrams per liter dissolved solids. No thermal springs in the caldera have geochemical characteristics similar to those of the geothermal reservoir fluids sampled in wells. Oxygen-18 and deuterium isotope concentrations of geothermal reservoir fluid indicate a meteoric origin. The moat valleys in

Water-Resources Investigations Report↗
USGS1995

Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-1994, with projections to 2020

This report describes a three-dimensional finite-difference ground-water-flow model of the Santa Fe Group aquifer system in the Albuquerque Basin, which comprises the Santa Fe Group (late Oligocene to middle Pleistocene age) and overlying valley and basin-fill deposits (Pleistocene to Holocene age). The model is designed to be flexible and adaptive to new geologic and hydrologic information as it becomes available, by using a geographic information system as a data-base manager to interface with the model. The aquifer system was defined and quantified in the model consistent with the current (July 1994) understanding of the structural and geohydrologic framework of the basin. Rather than putting the model through a rigorous calibration process, discrepancies between simulated and measured responses in hydraulic head were taken to indicate that the understanding of a local part of the aquifer system was incomplete or incorrect. The model simulates ground-water flow over an area of about 2,400 square miles to a depth of 1,730 to about 2,020 feet below the water table with 244 rows, 178 columns, and 11 layers. Of the 477,752 cells in the model, 310,376 are active. The top four model layers approximate the 80- foot thickness of alluvium in the incised and refilled valley of the Rio Grande to provide detail of the effect of ground-water withdrawals on the surface-water system. Away from the valley, these four layers represent the interval within the Santa Fe Group aquifer system between the computed predevelopment water table and a level 80 feet below the grade of the Rio Grande. The simulations include initial conditions (steady-state), the 1901-1994 historical period, and four possible ground-water withdrawal scenarios from 1994 to 2020. The model indicates that for the year ending in March 1994, net surface-water loss in the basin resulting from the City of Albuquerque's ground-water withdrawal totaled about 53,000 acre-feet. The balance of the about 123,000 acre-feet of withdrawal came from aquifer storage depletion (about 67,800 acre-feet) and captured or salvaged evapotranspiration (about 2,500 acrefeet). In the four scenarios projected from 1994 to 2020, City of Albuquerque annual withdrawals ranged from about 98,700 to about 177,000 acre-feet by the year 2020. The range of resulting surface-water loss was from about 62,000 to about 77,000 acre-feet. The range of aquifer storage depletion was from about 33,400 to about 95,900 acre-feet. Captured evapotranspiration and drain-return flow remained nearly constant for all scenarios. From 1994 to 2020, maximum projected declines in hydraulic head in the primary water-production zone of the aquifer (model layer 9) for the four scenarios ranged from 55 to 164 feet east of the Rio Grande and from 91 to 258 feet west of the river. Average declines in a 383.7-square-mile area around Albuquerque ranged from 28 to 65 feet in the production zone for the same period.

New Mexico↗
USGS2016

Potential postwildfire debris-flow hazards—A prewildfire evaluation for the Jemez Mountains, north-central New Mexico

Wildfire can substantially increase the probability of debris flows, a potentially hazardous and destructive form of mass wasting, in landscapes that have otherwise been stable throughout recent history. Although the exact location, extent, and severity of wildfire or subsequent rainfall intensity and duration cannot be known, probabilities of fire and debris‑flow occurrence for given locations can be estimated with geospatial analysis and modeling. The purpose of this report is to provide information on which watersheds might constitute the most serious potential debris - flow hazards in the event of a large - scale wildfire and subsequent rainfall in the Jemez Mountains. Potential probabilities and estimated volumes of postwildfire debris flows in both the unburned and previously burned areas of the Jemez Mountains and surrounding areas were estimated using empirical debris - flow models developed by the U.S. Geological Survey in combination with fire behavior and burn probability models developed by the U.S. Forest Service. Of the 4,998 subbasins modeled for this study, computed debris-flow probabilities in 671 subbasins were greater than 80 percent in response to the 100 - year recurrence interval, 30-minute duration rainfall event. These subbasins ranged in size from 0.01 to 6.57 square kilometers (km 2 ), with an average area of 0.29 km 2 , and were mostly steep, upstream tributaries to larger channels in the area. Modeled debris-flow volumes in 465 subbasins were greater than 10,000 cubic meters (m 3 ), and 14 of those subbasins had modeled debris‑flow volumes greater than 100,000 m 3 . The rankings of integrated relative debris - flow hazard indexes for each subbasin were generated by multiplying the individual subbasin values for debris - flow volume, debris‑flow probability, and average burn probability. The subbasins with integrated hazard index values in the top 2 percent typically are large, upland tributaries to canyons and channels primarily in the Upper Rio Grande and Rio Grande-Santa Fe watershed areas. No subbasins in this group have basin areas less than 1.0 km 2 . Many of these areas already had significant mass‑wasting episodes following the Las Conchas Fire in 2011. Other subbasins with integrated hazard index values in the top 2 percent are scattered throughout the Jemez River watershed area, including some subbasins in the interior of the Valles Caldera. Only a few subbasins in the top integrated hazard index group are in the Rio Chama watershed area. This prewildfire assessment approach is valuable to resource managers because the analysis of the debris-flow threat is made before a wildfire occurs, which facilitates prewildfire management, planning, and mitigation. In north‑central New Mexico, widespread watershed restoration efforts are being done to safeguard vital watersheds against the threat of catastrophic wildfire. This study was designed to help select ideal locations for the restoration efforts that could have the best return on investment.

New Mexico↗
USGS2016

Groundwater-flow model of the northern High Plains aquifer in Colorado, Kansas, Nebraska, South Dakota, and Wyoming

The High Plains aquifer is a nationally important water resource underlying about 175,000 square miles in parts of eight states: Colorado, Kansas, Oklahoma, Nebraska, New Mexico, South Dakota, Texas, and Wyoming. Droughts across much of the Northern High Plains from 2001 to 2007 have combined with recent (2004) legislative mandates to elevate concerns regarding future availability of groundwater and the need for additional information to support science-based water-resource management. To address these needs, the U.S. Geological Survey began the High Plains Groundwater Availability Study to provide a tool for water-resource managers and other stakeholders to assess the status and availability of groundwater resources. A transient groundwater-flow model was constructed using the U.S. Geological Survey modular three-dimensional finite-difference groundwater-flow model with Newton-Rhapson solver (MODFLOW–NWT). The model uses an orthogonal grid of 565 rows and 795 columns, and each grid cell measures 3,281 feet per side, with one variably thick vertical layer, simulated as unconfined. Groundwater flow was simulated for two distinct periods: (1) the period before substantial groundwater withdrawals, or before about 1940, and (2) the period of increasing groundwater withdrawals from May 1940 through April 2009. A soil-water-balance model was used to estimate recharge from precipitation and groundwater withdrawals for irrigation. The soil-water-balance model uses spatially distributed soil and landscape properties with daily weather data and estimated historical land-cover maps to calculate spatial and temporal variations in potential recharge. Mean annual recharge estimated for 1940–49, early in the history of groundwater development, and 2000–2009, late in the history of groundwater development, was 3.3 and 3.5 inches per year, respectively. Primary model calibration was completed using statistical techniques through parameter estimation using the parameter estimation suite of software with Tikhonov regularization. Calibration targets for the groundwater model included 343,067 groundwater levels measured in wells and 10,820 estimated monthly stream base flows at streamgages. A total of 1,312 parameters were adjusted during calibration to improve the match between calibration targets and simulated equivalents. Comparison of calibration targets to simulated equivalents indicated that, at the regional scale, the model correctly reproduced groundwater levels and stream base flows for 1940–2009. This comparison indicates that the model can be used to examine the likely response of the aquifer system to potential future stresses. Mean calibrated recharge for 1940–49 and 2000–2009 was smaller than that estimated with the soil-water-balance model. This indicated that although the general spatial patterns of recharge estimated with the soil-water-balance model were approximately correct at the regional scale of the Northern High Plains aquifer, the soil-water-balance model had overestimated recharge, and adjustments were needed to decrease recharge to improve the match of the groundwater model to calibration targets. The largest components of the simulated groundwater budgets were recharge from precipitation, recharge from canal seepage, outflows to evapotranspiration, and outflows to stream base flow. Simulated outflows to irrigation wells increased from 7 percent of total outflows in 1940–49 to 38 percent of 1970–79 total outflows and 49 percent of 2000–2009 total outflows.

Colorado, Kansas, Nebraska, South Dakota, Wyoming↗
USGS2005

Rainfall-runoff in the Albuquerque, New Mexico, area: Measurements, analyses and comparisons

Albuquerque, New Mexico, has experienced significant growth over the last 20 years like many other cities in the Southwestern United States. While the US population grew by 37% between the 1970 and 2000 censuses, the growth for Albuquerque was 83%. More people mean more development and increased problems of managing runoff from urbanizing watersheds. The U.S. Geological Survey (USGS) in cooperation with the Albuquerque Arroyo Metropolitan Flood Control Authority (AMAFCA) and the City of Albuquerque has maintained a rainfall-runoff data collection program since 1976. The data from measured precipitation events can be used to verify hydrologic modeling. In this presentation, data from a representative gaged watershed is analyzed and discussed to set the overall framework for the rainfall-runoff process in the Albuquerque area. Of particular interest are the basic relationships between rainfall and watershed runoff response and an analysis of curve numbers as an indicator of runoff function. In urbanized areas, four land treatment types (natural, irrigated lawns, compacted soil, and impervious) are used to define surface infiltration conditions. Rainfall and runoff gage data are used to compare curve number (CN) and initial abstraction/uniform infiltration (IA/INF) techniques in an Albuquerque watershed. The IA/INF method appears to produce superior results over the CN method for the measured rainfall events.

Conference Paper↗
USGS2022

Database of water quality and groundwater elevation within and surrounding the Lee Acres Landfill, New Mexico, 1985–2020

This report describes the background information related to and the contents of the Lee Acres-Giant Bloomfield Refinery Database (LAGBRD), which is a compilation of monitoring data collected at the Lee Acres Landfill and the Giant Bloomfield Refinery near Farmington, New Mexico. LAGBRD includes monitoring data from as early as 1985, when awareness was increasing regarding contamination from liquid waste lagoons at the landfill and fuel releases at the refinery. Water quality and groundwater elevation data from sampling locations at the landfill and the refinery are included in the database. LAGBRD was compiled by the U.S. Geological Survey in cooperation with the Bureau of Land Management, which operates the Lee Acres Landfill, in order to facilitate future studies into the characteristics of groundwater contamination and background geochemistry at the landfill and refinery sites.

New Mexico↗
USGS1971

Coronadite — Modes of occurrence and origin

The lead manganate, "coronadite," was first recognized at the Coronado mine in the Morenci district, Arizona, by Lindgren in 1903. Several years later, the identity of the mineral was questioned and it was not until 1932 that Orcel recognized it in material from Morocco. Since 1955, the mineral has been recognized at numerous places; in the USSR, east of the Ural Mountains, in several districts in Morocco, England, Australia, and India. In recent years, coronadite had been identified at numerous localities in New Mexico, Arizona, Nevada, and California by the writer and others. At this time, it has been identified at 22 localities, and in the opinion of this writer, it will be found at many more places if it is sought for carefully. Author's review of the known occurrences of coronadite and interpretation of the modes of geologic environment show that the mineral is found in veins and hot spring aprons, where it seems to have been deposited by hydrothermal waters from depth and that it is one of the manganese oxide minerals deposited as sediments. Probably it is more widely found in assemblages of minerals of supergene origin.

Arizona, Asturias, California, Chihuahua, Durango,↗
USGS2017

U.S. Geological Survey Karst Interest Group Proceedings, San Antonio, Texas, May 16–18, 2017

Introduction and Acknowledgments Karst aquifer systems are present throughout parts of the United States and some of its territories, and have developed in carbonate rocks (primarily limestone and dolomite) and evaporites (gypsum, anhydrite, and halite) that span an interval of time encompassing more than 550 million years. The depositional environments, diagenetic processes, post-depositional tectonic events, and geochemical weathering processes that form karst aquifers are varied and complex. These factors involve biological, chemical, and physical changes that when combined with the diverse climatic regimes in which karst development has taken place, result in the unique dual- or triple-porosity nature of karst aquifers. These complex hydrogeologic systems typically represent challenging and unique conditions to scientists attempting to study groundwater flow and contaminant transport in these terrains. The dissolution of carbonate rocks and the subsequent development of distinct and beautiful landscapes, caverns, and springs have resulted in the most exceptional karst areas being designated as national or state parks. Tens of thousands of similar areas in the United States have been developed into commercial caverns and known privately owned caves. Both public and private properties provide access for scientists to study the flow of groundwater in situ . Likewise, the range and complexity of landforms and groundwater flow systems associated with karst terrains are enormous, perhaps more than for any other aquifer type. Karst aquifers and landscapes that form in tropical areas, such as the cockpit karst along the north coast of Puerto Rico, differ greatly from karst landforms in more arid climates, such as the Edwards Plateau in west-central Texas or the Guadalupe Mountains near Carlsbad, New Mexico, where hypogenic processes have played a major role in speleogenesis. Many of these public and private lands also contain unique flora and fauna associated with these karst hydrogeologic systems. As a result, numerous federal, state, and local agencies have a strong interest in the study of karst terrains. Many of the major springs and aquifers in the United States have developed in carbonate rocks, such as the Floridan aquifer system in Florida and parts of Alabama, Georgia, and South Carolina; the Ozark Plateaus aquifer system in parts of Arkansas, Kansas, Missouri, and Oklahoma; and the Edwards-Trinity aquifer system in west-central Texas. These aquifers, and the springs that discharge from them, serve as major water-supply sources and form unique ecological habitats. Competition for the water resources of karst aquifers is common, and urban development and the lack of attenuation of contaminants in karst areas due to dissolution features that form direct pathways into karst aquifers can impact the ecosystem and water quality associated with these aquifers. The concept for developing a platform for interaction among scientists within the U.S. Geological Survey (USGS) working on karst-related studies evolved from the November 1999 National Groundwater Meeting of the USGS. As a result, the Karst Interest Group (KIG) was formed in 2000. The KIG is a loose-knit, grass-roots organization of USGS and non-USGS scientists and researchers devoted to fostering better communication among scientists working on, or interested in, karst science. The primary mission of the KIG is to encourage and support interdisciplinary collaboration and technology transfer among scientists working in karst areas. Additionally, the KIG encourages collaborative studies between the different mission areas of the USGS as well as with other federal and state agencies, and with researchers from academia and institutes. To accomplish its mission, the KIG has organized a series of workshops that have been held near nationally important karst areas. To date (2017) seven KIG workshops, including the workshop documented in this report, have been held. The workshops typically include oral and poster sessions on selected karst-related topics and research, as well as field trips to local karst areas. To increase non-USGS participation an effort was made for the workshops to be held at a university or institute beginning with the fourth workshop. Proceedings of the workshops are published by the USGS and are available online at the USGS publications warehouse https://pubs.er.usgs.gov/ by using the search term “karst interest group.” The first KIG workshop was held in St. Petersburg, Florida, in 2001, in the vicinity of the large springs and other karst features of the Floridan aquifer system. The second KIG workshop was held in 2002, in Shepherdstown, West Virginia, in proximity to the carbonate aquifers of the northern Shenandoah Valley, and highlighted an invited presentation on karst literature by the late Barry F. Beck of P.E. LaMoreaux and Associates. The third KIG workshop was held in 2005, in Rapid City, South Dakota, near evaporite karst features in limestones of the Madison Group in the Black Hills of South Dakota. The Rapid City KIG workshop included field trips to Wind Cave National Park and Jewel Cave National Monument, and featured a presentation by Thomas Casadevall, then USGS Central Region Director, on the status of Earth science at the USGS. The fourth KIG workshop in 2008 was hosted by the Hoffman Environmental Research Institute and Center for Cave and Karst Studies at Western Kentucky University in Bowling Green, Kentucky, near Mammoth Cave National Park and karst features of the Chester Upland and Pennyroyal Plateau. The workshop featured a late-night field trip into Mammoth Cave led by Rickard Toomey and Rick Olsen, National Park Service. The fifth KIG workshop in 2011 was a joint meeting of the USGS KIG and University of Arkansas HydroDays, hosted by the Department of Geosciences at the University of Arkansas in Fayetteville. The workshop featured an outstanding field trip to the unique karst terrain along the Buffalo National River in the southern Ozarks, and a keynote presentation on paleokarst in the United States was delivered by Art and Peggy Palmer. The sixth KIG workshop was hosted by the National Cave and Karst Research Institute (NCKRI) in 2014, in Carlsbad, New Mexico. George Veni, Director of the NCKRI, served as a co-chair of the workshop with Eve Kuniansky of the USGS. The workshop featured speaker Dr. Penelope Boston, Director of Cave and Karst Studies at New Mexico Tech, Socorro, and Academic Director at the NCKRI, who addressed the future of karst research. The field trip on evaporite karst of the lower Pecos Valley was led by Lewis Land (NCKRI karst hydrologist), and the field trip on the geology of Carlsbad Caverns National Park was led by George Veni. This current seventh KIG workshop is being held in San Antonio at the University of Texas at San Antonio (UTSA). This 2017 workshop is being hosted by the Department of Geological Sciences’ Student Geological Society (SGS), and student chapters of the American Association of Petroleum Geologists (AAPG) and Association of Engineering Geologists (AEG), with support by the UTSA Department of Geological Sciences and Center for Water Research. The UTSA student chapter presidents, Jose Silvestre (SGS), John Cooper (AAPG), and Tyler Mead (AEG) serve as co-chairs of the 2017 workshop with Eve Kuniansky of the USGS. The technical session committee is chaired by Eve Kuniansky, USGS, and includes Michael Bradley, Tom Byl, Rebecca Lambert, John Lane, and James Kaufmann, all USGS, and Patrick Tucci, retired USGS. The logistics committee includes Amy Clark, Yongli Gao, and Lance Lambert (Department Chair), UTSA Department of Geological Sciences; and Ryan Banta and Allan Clark, USGS, San Antonio, Texas. The field trip committee is chaired by Allan Clark and includes Amy Clark, Yongli Gao, and Keith Muehlestein, UTSA; Marcus Gary, Edwards Aquifer Authority and University of Texas at Austin; Ron Green, Southwest Research Institute; Geary Schindel, Edwards Aquifer Authority; and George Veni, NCKRI. Additionally, two organizations have assisted the UTSA student chapters in hosting the meeting by donating funds to the chapters: the Edwards Aquifer Authority, San Antonio, Texas, and the Barton Springs Edwards Aquifer Authority, Austin, Texas. Additionally, Yongli Gao, Center for Water Research and Department of Geological Sciences, UTSA, helped develop sessions on cave and karst research in China for this workshop. These proceedings could not have been accomplished without the assistance of Lawrence E. Spangler as co-editor who not only has subject matter expertise, but also serves as an editor with the USGS Science Publishing Network. We sincerely hope that this workshop continues to promote future collaboration among scientists of varied and diverse backgrounds, and improves our understanding of karst aquifer systems in the United States and its territories. The extended abstracts of USGS authors were peer reviewed and approved for publication by the USGS. Articles submitted by university researchers and other federal and state agencies did not go through the formal USGS peer review and approval process, and therefore may not adhere to USGS editorial standards or stratigraphic nomenclature. However, all articles had a minimum of two peer reviews and were edited for consistency of appearance in the proceedings. The use of trade, firm or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The USGS Water Availability and Use Science Program funded the publication costs of the proceedings.

Scientific Investigations Report↗
USGS2005

Record of the North American southwest monsoon from Gulf of Mexico sediment cores

Summer monsoonal rains (the southwest monsoon) are an important source of moisture for parts of the southwestern United States and northern Mexico. Improved documentation of the variability in the southwest monsoon is needed because changes in the amount and seasonal distribution of precipitation in this semiarid region of North America influence overall water supply and fire severity. Comparison of abundance variations in the planktic foraminifer Globigerinoides sacculifer in marine cores from the western and northern Gulf of Mexico with terrestrial proxy records of precipitation (tree-ring width and packrat-midden occurrences) from the southwestern United States indicate that G. sacculifer abundance is a proxy for the southwest monsoon on millennial and submillennial time scales. The marine record confirms the presence of a severe multicentury drought centered ca. 1600 calendar (cal.) yr B.P. as well as several multidecadal droughts that have been identified in a long tree-ring record spanning the past 2000 cal. yr from westcentral New Mexico. The marine record further suggests that monsoon circulation, and thus summer rainfall, was enhanced in the middle Holocene (ca. 6500-4500 14C yr B.P.; ca. 6980-4710 cal. yr B.P.). The marine proxy provides the potential for constructing a highly resolved, well-dated, and continuous history of the southwest monsoon for the entire Holocene. ?? 2005 Geological Society of America.

Geology↗
USGS2002

Multibeam mapping of selected areas of the outer continental shelf, northwestern Gulf of Mexico: Data, images, and GIS

Following the publication of high-resolution (5-meter spatial resolution) multibeam echosounder (MBES) images of the Flower Garden Banks National Marine Sanctuary area of the northwestern Gulf of Mexico (Gardner et al., 1998), the Flower Garden Banks National Marine Sanctuary (FGBNMS) and the Minerals Management Service (MMS) have been interested in additional MBES data in the area. A coalition of FGBNMS, MMS, and the U.S. Geological Survey (USGS) was formed to map additional areas of interest in the northwestern Gulf of Mexico (fig. 1) in 2002. FGBNMS chose the survey areas, and the USGS chose the MBES. MMS and FGBNMS funded the mapping, and the USGS organized the ship and multibeam systems through a cooperative agreement between the USGS and the University of New Brunswick. The objective of the cruise was to map 12 regions of interest to MMS and the FGBNMS, including Alderdice, Sonnier, Geyer, Bright, Rankin (1 and 2), Jakkula, McNeil, Bouma, McGrail, Rezak, and Sidner Banks.

Gulf Of Mexico↗
USGS2003

Rocky Mountain snowpack chemistry at selected sites for 2001

Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants in a network of high-elevation sites. Samples of seasonal snowpacks at 57 geographically distributed sites, in a regional network from New Mexico to Montana, were collected and analyzed for major ions (including ammonium, nitrate, and sulfate), alkalinity, and dissolved organic carbon during 2001. Sites selected in this report have been sampled annually since 1993, enabling identification of increases or decreases in chemical concentrations from year to year. Spatial patterns in snowpack-chemical data for concentrations of ammonium, nitrate, and sulfate indicate that concentrations of these acid precursors in less developed areas of the region are lower than concentrations in the heavily developed areas. Results for the 2001 snowpack-chemistry analyses, however, indicate increases in concentrations of ammonium and nitrate in particular at sites where past concentrations typically were lower. Since 1993, concentrations of nitrate and sulfate were highest from snowpack samples in northern Colorado that were collected from sites adjacent to the Denver metropolitan area to the east and the coal-fired powerplants to the west. In 2001, relatively high concentrations of nitrate (12.3 to 23.0 microequivalents per liter (?eq/L) and sulfate (7.7 to 12.5 ?eq/L) were detected in Montana and Wyoming. Ammonium concentrations were highest in north-central Colorado (14.5 to 16.9 ?eq/L) and southwestern Montana (12.8 to 14.2 ?eq/L).

Open-File Report↗
USGS2016

Potentiometric surfaces, summer 2013 and winter 2015, and select hydrographs for the Southern High Plains aquifer, Cannon Air Force Base, Curry County, New Mexico

Cannon Air Force Base (Cannon AFB) is located in the High Plains physiographic region of east-central New Mexico, about 5 miles west of Clovis, New Mexico. The area surrounding Cannon AFB is primarily used for agriculture, including irrigated cropland and dairies. The Southern High Plains aquifer is the principal source of water for Cannon AFB, for the nearby town of Clovis, and for local agriculture and dairies. The Southern High Plains aquifer in the vicinity of Cannon AFB consists of three subsurface geological formations: the Chinle Formation of Triassic age, the Ogallala Formation of Tertiary age, and the Blackwater Draw Formation of Quaternary age. The Ogallala Formation is the main water-yielding formation of the Southern High Plains aquifer. Groundwater-supplied, center-pivot irrigation dominates pumping from the Southern High Plains aquifer in the area surrounding Cannon AFB, where the irrigation season typically extends from early March through October. The U.S. Geological Survey has been monitoring groundwater levels in the vicinity of Cannon AFB since 1954 and has developed general potentiometric-surface maps that show groundwater flow from northwest to southeast in the study area. While previous potentiometric-surface maps show the general direction of groundwater flow, a denser well network is needed to show details of groundwater flow at a local scale. Groundwater levels were measured in 93 wells during summer 2013 and 100 wells during winter 2015. The summer and winter potentiometric-surface maps display the presence of what is interpreted to be a groundwater trough trending from the northwest to the southeast through the study area. This groundwater trough may be the hydraulic expression of a Tertiary-age paleochannel. Groundwater north of the trough flows in a southerly direction into the trough, and groundwater south of the trough flows in an easterly direction into the trough. During the 18-month period between summer 2013 and winter 2015, changes in groundwater levels ranged from a rise of 10.0 to a decline of 3.8 feet. The regions to the north and south of the groundwater trough contained the majority of the rises in groundwater levels, whereas the regions within the trough contained the majority of the declines in groundwater levels. In contrast, the long-term groundwater-level trend in wells with 20 to 60 years of record is a steady decline in average annual water levels, with declines ranging from 0.41 to 2.81 feet per year. Overall, the northwestern part of the study area exhibits the smallest average annual declines, while the southeastern part of the study area exhibits the largest average annual declines.

New Mexico↗
USGS2007

Questa Baseline and Pre-Mining Ground-Water Quality Investigation. 24. Seismic Refraction Tomography for Volume Analysis of Saturated Alluvium in the Straight Creek Drainage and Its Confluence With Red River, Taos County, New Mexico

As part of a research effort directed by the New Mexico Environment Department to determine pre-mining water quality of the Red River at a molybdenum mining site in northern New Mexico, we used seismic refraction tomography to create subsurface compressional-wave velocity images along six lines that crossed the Straight Creek drainage and three that crossed the valley of Red River. Field work was performed in June 2002 (lines 1-4) and September 2003 (lines 5-9). We interpreted the images to determine depths to the water table and to the top of bedrock. Depths to water and bedrock in boreholes near the lines correlate well with our interpretations based on seismic data. In general, the images suggest that the alluvium in this area has a trapezoidal cross section. Using a U.S. Geological Survey digital elevation model grid of surface elevations of this region and the interpreted elevations to water table and bedrock obtained from the seismic data, we generated new models of the shape of the buried bedrock surface and the water table through surface interpolation and extrapolation. Then, using elevation differences between the two grids, we calculated volumes of dry and wet alluvium in the two drainages. The Red River alluvium is about 51 percent saturated, whereas the much smaller volume of alluvium in the tributary Straight Creek is only about 18 percent saturated. When combined with average ground-water velocity values, the information we present can be used to determine discharge of Straight Creek into Red River relative to the total discharge of Red River moving past Straight Creek. This information will contribute to more accurate models of ground-water flow, which are needed to determine the pre-mining water quality in the Red River.

Scientific Investigations Report↗
USGS1982

Estimates of vertical hydraulic conductivity and regional ground-water flow rates in rocks of Jurassic and Cretaceous age, San Juan Basin, New Mexico and Colorado

The San Juan structural basin northwestern New Mexico was modeled in three dimensions using a finite-difference, steady-state model. The modeled space was divided into seven layers of square prisms that were 6 miles on a side in the horizontal directions. In the vertical direction, the layers of prisms ranged in thickness from 300 to 1,500 feet. The model included the geologic section between the base of the Entrada Sandstone and the top of Mesaverde Group. Principal aquifers in this section are mostly confined and include the Entrada Sandstone, the Westwater Canyon Member of the Morrison Formation , and the Gallup Sandstone. Values for vertical hydraulic conductivities from 10 to the minus 12th power to 10 to the minus 11th power feet per second for the confining layers gave a good simulation of head differences between layers, but a sensitivity analysis indicated that these values could be between 10 and 100 times greater. The model-derived steady-state flow was about 30 cubic feet per second. About one-half of the flow was in the San Juan River drainage basin about one-third in the Rio Grande drainage basin, and one-sixth in the Puerco River drainage basin. (USGS)

Water-Resources Investigations Report↗