SEARCH · Geology Reports
Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Ground water in the Navajo Sandstone near Caineville, Wayne County, Utah, was studied during 1975-77 as part of an investigation of water in bedrock in the lower Dirty Devil River basin area. The purpose of the study near Caineville was to determine the water-bearing properties of the Navajo by utilizing data obtained mainly during test drilling and aquifer testing by the Intermountain Power Project.
The black-capped chickadee ( Parus atricapillus ) Habitat Suitability Index (HSI) model provides a quantitative rating of the capability of a habitat to support breeding, based on measures related to food and nest site availability. The model assumption that tree canopy volume can be predicted from measures of tree height and canopy closure was tested using data from foliage volume studies conducted in the riparian cottonwood habitat along the South Platte River in Colorado. Least absolute deviations (LAD) regression showed that canopy cover and over story tree height yielded volume predictions significantly lower than volume estimated by more direct methods. Revisions to these model relations resulted in improved predictions of foliage volume. The relation between the HSI and estimates of black-capped chickadee population densities was examined using LAD regression for both the original model and the model with the foliage volume revisions. Residuals from these models were compared to residuals from both a zero slope model and an ideal model. The fit model for the original HSI differed significantly from the ideal model, whereas the fit model for the original HSI did not differ significantly from the ideal model. However, both the fit model for the original HSI and the fit model for the revised HSI did not differ significantly from a model with a zero slope. Although further testing of the revised model is needed, its use is recommended for more realistic estimates of tree canopy volume and habitat suitability.
To assess the potential impact of metal and acid contamination from mine-waste piles, it is important to identify the mineralogic source of trace metals and their mode of occurrence. Microscopic analysis of mine-waste samples from both hard-rock and coalmine waste samples demonstrate a microstructural control, as well as mineralogic control, on the source and release of trace metals into local water systems. The samples discussed herein show multiple periods of sulfide mineralization with varying concentrations of trace metals. In the first case study, two proprietary hard-rock mine-waste samples exposed to a series of humidity cell tests (which simulate intense chemical weathering conditions) generated acid and released trace metals. Some trace elements of interest were: arsenic (45-120 ppm), copper (60-320 ppm), and zinc (30-2,500 ppm). Untested and humidity cell-exposed samples were studied by X-ray diffraction, scanning electron microscope with energy dispersive X-ray (SEM/EDX), and electron microprobe analysis. Studies of one sample set revealed arsenic-bearing pyrite in early iron- and magnesium-rich carbonate-filled microveins, and iron-, copper-, arsenic-, antimony-bearing sulfides in later crosscutting silica-filled microveins. Post humidity cell tests indicated that the carbonate minerals were removed by leaching in the humidity cells, exposing pyrite to oxidative conditions. However, sulfides in the silica-filled veins were more protected. Therefore, the trace metals contained in the sulfides within the silica-filled microveins may be released to the surface and (or) ground water system more slowly over a greater time period. In the second case study, trace metal-rich pyrite-bearing coals from the Warrior Basin, Alabama were analyzed. Arsenic-bearing pyrite was observed in a late-stage pyrite phase in microfaults and microveins that crosscut earlier arsenic.
The federally endangered Tar River spinymussel (Elliptio steinstansana) is endemic to the Tar River and Neuse River systems in North Carolina. The extent to which water quality limits Tar River spinymussels’ recovery is important to establish, and one aspect of that is understanding the species’ pollutant sensitivity. The primary objectives of this study were to 1) develop captive propagation and culture methods for Tar River spinymussels; 2) determine the pollutant sensitivity of captively propagated Tar River spinymussels; 3) examine the utility of the non-endangered yellow lance (Elliptio lanceolata), yellow lampmussel (Lampsilis cariosa) and notched rainbow (Villosa constricta) as surrogates for the Tar River spinymussels’ chemical sensitivity; 4) develop a 7-d method for conducting effluent toxicity tests starting with newly transformed mussels; 5) assess the toxicity of municipal wastewater effluents discharged into the Tar River spinymussels’ current and historic habitat; and, 6) evaluate the protection afforded by existing effluent toxicity test requirements.
A 3-month-long, large-scale flume experiment involving research and testing of selected conventional and surrogate bedload-monitoring technologies was conducted in the Main Channel at the St. Anthony Falls Laboratory under the auspices of the National Center for Earth-surface Dynamics. These experiments, dubbed StreamLab06, involved 25 researchers and volunteers from academia, government, and the private sector. The research channel was equipped with a sediment-recirculation system and a sediment-flux monitoring system that allowed continuous measurement of sediment flux in the flume and provided a data set by which samplers were evaluated. Selected bedload-measurement technologies were tested under a range of flow and sediment-transport conditions. The experiment was conducted in two phases. The bed material in phase I was well-sorted siliceous sand (0.6-1.8 mm median diameter). A gravel mixture (1-32 mm median diameter) composed the bed material in phase II. Four conventional bedload samplers – a standard Helley-Smith, Elwha, BLH-84, and Toutle River II (TR-2) sampler – were manually deployed as part of both experiment phases. Bedload traps were deployed in study Phase II. Two surrogate bedload samplers – stationarymounted down-looking 600 kHz and 1200 kHz acoustic Doppler current profilers – were deployed in experiment phase II. This paper presents an overview of the experiment including the specific data-collection technologies used and the ambient hydraulic, sediment-transport and environmental conditions measured as part of the experiment. All data collected as part of the StreamLab06 experiments are, or will be available to the research community.
A test-drilling program was conducted by the U.S. Geological Survey in the upper Sevier River drainage basin (fig. 1) in the summer of 1962. The program was part of a ground-water investigation made in cooperation with the Utah State Engineer. The drilling was financed cooperatively through the State Engineer by the U.S. Geological Survey, Garfield, Piute, Sevier, Sanpete, and Millard Counties, and various water users within those counties. Drilling began in May and continued through September 1962, and 21 test holes were drilled.
We describe a field compatible molecular diagnostic test for two new species of Ceratocystis that infect `ōhi`a (Metrosideros polymorpha) and cause the disease commonly known as Rapid `Ōhi`a Death. The diagnostic is based on amplification of a DNA locus within the internal transcribed spacer region that separates fungal 5.8S ribosomal genes. The assay uses forward and reverse primers, recombinase polymerase, and a fluorescent probe that allows isothermal (40oC) amplification and simultaneous quantification of a 115 base pair product with a battery operated fluorometer. DNA extractions are field compatible and can be done by heating wood drill shavings to 100oC in Instagene® solution containing Chelex® resin to bind potential amplification inhibitors. The initial heat treatment is followed by a short bead beating step with steel ball bearings and zirconium beads to release DNA. DNA is subsequently purified with a magnetic bead based extraction method that does not require silica columns or centrifugation. The assay is designed around a portable “lab-in-a-suitcase” platform that includes a portable fluorometer, miniature centrifuge, and heat block that operate off either 120V AC power sources or a 12 volt battery with a portable inverter, a magnetic rack designed for 1.5 ml tubes and magnetic bead DNA purification, pipettes and consumable reagents and tubes. The entire assay from DNA extraction to results can be performed in less than 90 minutes on up to six independent samples plus a positive and negative control. Sensitivity based on suspensions of Ceratocystis endoconidia (spores) that were added to wood shavings and processed under field conditions by Instagene® magnetic bead DNA extraction was up to 163 spores/mg wood for Species A and 55 spores/mg wood for Species B in 95% of replicates as determined by probit analysis. Sensitivity increased 5–10 fold to 19 spores/mg wood for Species A and 9 spores/mg wood for Species B when extractions were performed with a commercial, silica column based DNA purification kit. The test did not cross react with other common fungi that have been isolated from `ōhi`a.
Behavioral functions essential for growth and survival can be dramatically altered by sublethal exposure to toxicants. Measures of these behavioral responses are effective in detecting adverse effects of sublethal contaminant exposure. Behavioral responses of fishes can be qualitatively and quantitatively evaluated during routine toxicity tests. At selected intervals of exposure, qualitative evaluations are accomplished through direct observations, whereas video recordings are used for quantitative evaluations. Standardized procedures for behavioral evaluation are readily applicable to different fish species and provide rapid, sensitive, and ecologically relevant assessments of sublethal exposure. The methods are readily applied to standardized test protocols.
As arid sites in the western United States are increasingly sought for disposal of the Nation's hazardous wastes and as volumes of locally generated wastes increase, concern about the potential effect of contaminants on environmental quality is being raised. Studies at the U.S. Geological Survey's Amargosa Desert research site near Beatty, Nevada are being done to evaluate mechanisms that can affect waste isolation in an arid environment. Precipitation at the site averages about 108 mm yr -1 . Results have shown that, under undisturbed conditions, the naturally stratified soils in combination with native plants are effective in limiting the potential for percolation of precipitation. Under nonvegetated waste-site conditions, data indicated the accumulation and shallow, but continued, penetration of infiltrated water, However, water potentials below the test trenches and below the 2-m depth for nonvegetated soil indicated the persistence of an upward driving force for water flow during the 5-yr test period. General trends in trench-cover subsidence suggested a positive relation with cumulative precipitation, but subsidence did not appear to have a measurable effect on the water balance. Erosion rates were inversely related to near-surface rock-fragment content. Results suggest that the ultimate fate of contaminants buried at properly managed solid-waste sites may be determined largely by the interactions among climate and the surface-cover features of the disposal facility, and how these factors change with time.
Partitioning of Mg and Mn between titanomagnetite and ferrian ilmenite of volcanic rocks provides a test for equilibrium between coexisting phases. A plot of log(Mg/Mn)-, vs. log(Mg/Mn),, for 213 homogeneous oxide pairs from volcanic rocks yields a straight line over more than two orders of magnitude variation in Mg/Mn. Analyses that plot within reasonable limits of analytical precision of this line are consistent with preservation of equilibrium compositions. The test appears to be valid for fresh volcanic rocks but may not be applicable to oxides in metamorphic, plutonic, and altered volcanic rocks in which oxide minerals typicatly have oxidized or exsolved at subsolidus temperatures. It can be used to discriminate between multiple populations of an oxide phase or to evaluate equilibration of inclusions in silicate phenocrysts for Fe-Ti oxide geothermometry and oxygen barometry.
Acoustics and other surrogates can be used to accurately and cost-effectively provide time-series estimates of suspended-sediment concentration and load, which is essential for creating informed solutions to many sediment-related environmental, engineering, and agricultural concerns. Interagency efforts in recent years have advanced the testing, methods development, operational guidelines, and training on sediment acoustics. This extended abstract provides an update on horizontal profiling methodologies and introduces the testing of the LISST-ABS (Acoustic Backscatter Sensor).
The aerial camera testing project lays the groundwork for the collection of aerial imagery that will be used in the creation of the next iteration of systemic land cover/land use data for the Upper Mississippi River System. Prior to acquisition in the summer of 2020, the new 4-band aerial camera will be assessed for image quality at various resolutions and be compared to the camera used for the 2010/2011 collection. Systemic aerial imagery has been acquired, and vegetation datasets derived from that imagery, by the Upper Mississippi River Restoration Program’s Long Term Resource Monitoring element on a decadal basis beginning in 1989 and follow-up imagery missions in 2000 and 2010/2011. Remote sensing and geographic information system technology has changed dramatically during this time, transitioning from a workflow based on 9-inch by 9-inch aerial film-based cameras to today’s 80-megapixel four-band digital camera. In addition to the camera testing, this report also provides historical information of previous aerial imagery acquisition efforts and how that process has continued to advance in the 30 years since the Program’s genesis.
Mosquito-borne avian malaria Plasmodium relictum is a key limiting factor for endemic Hawaiian forest birds. In the past decade, populations of Kaua‘i’s endemic forest birds have been in a steep decline due to an increase in malaria transmission. To evaluate the use of available biopesticides for short-term mosquito control we tested the efficacy of the biopesticide VectoMax® FG against Culex quinquefasciatus larvae in naturally occurring perched stream pools, seeps, and ground pools in forest bird habitat in Kaua‘i’s remote Alaka‘i Plateau. We also tested the efficacy of conventional and newer traps and attractants for the capture of adult Culex quinquefasciatus in Hawaiian rain forests and monitored adult mosquito populations at the Kaua‘i field site. During field trials conducted on Hawai‘i Island we captured more Culex quinquefasciatus in gravid traps than in host-seeking traps. Among the host-seeking traps, Biogents BG-Sentinel 2 traps baited with CO2 and BG-Lure caught more Culex quinquefasciatus and Aedes japonicus japonicus than CDC (Centers for Disease Control and Prevention) traps baited with compressed CO2, CDC traps baited with dry ice, or Biogents BG-Sentinel 2 traps baited with BG-Lure and octenol but not CO2. Both Biogents BG-Sentinel 2 and CDC miniature traps baited with compressed CO2 or dry ice captured significantly more Culex quinquefasciatus than Biogents BG-Sentinel 2 traps baited with octenol and BG-Lure but without CO2. We also found that gravid traps baited with timothy hay infusions caught significantly more Culex quinquefasciatus than traps baited with either a commercial gravid mosquito attractant or an infusion made with pelleted rabbit feed. Traps baited with an infusion of timothy hay and donkey dung were the most effective for Culex quinquefasciatus. On Kaua‘i, we operated Biogents BG-Sentinel 2 traps baited with CO2 and gravid traps and captured 29 mosquitoes in 182 trap-nights from October–November 2016 and 126 mosquitoes in 254 trap-nights from September–October 2017. Contrary to our findings on Hawai‘i Island, most mosquitoes (96%) were captured in Biogents BG-Sentinel 2 traps indicating considerable site-to-site variability in trap efficacy. Weekly adult trapping on Kaua‘i indicates Culex quinquefasciatus populations peaked in October but provided no reliable evidence that larval control had any significant effect on adult populations. Overall, VectoMax® FG was very effective at larval control reducing larval abundance by 95% at 48 hours and out to 1-week post-treatment. Treatment was most effective (100% at 1-week post-treatment) in perched pools when early instar larvae were present and least effective in seeps when pupae and fourth instar larvae were most common. Although post-treatment counts fluctuated dramatically, we observed no evidence of population level impacts to the two most common non-target invertebrates: the water strider Microvelia vagans and endemic damselfly naiads (Megalagrion sp.). VectoMax® FG appears to be an effective and safe biopesticide for the local control of Culex quinquefasciatus larvae in forest bird habitat in the Alaka‘i Plateau. Further studies will be necessary to determine if local larval control significantly reduces adult mosquito abundance and, ultimately, avian malaria transmission, and if there are long term, non-target effects associated with repeated use of VectoMax® FG in natural Hawaiian waterways.
Land use change maps prepared from high-resolution, high-altitude aerial photographs for the period 1970 to 1972 of the CARETS (Central Atlantic Regional Ecological Test Site) project were analyzed for accuracy. To test for errors of commission, all outlined areas (polygons) of land use change on five l:100000-scale maps were examined for accuracy. An estimate of the errors of omission was obtained by comparing the land use change polygons mapped for the Norfolk SMSA (Norfolk and Virginia Beach Standard Metropolitan Statistical Area) with the changes mapped in a more detailed study of the same area. The results of these studies showed that the largest number of errors was caused by misregistration of the land use change map to the 1970 land use map; however, only a very small percentage of the total land area of the land use change was affected by misregistration. In the Norfolk SMSA, which is an area of rapid urban growth, many of the land use changes had not been mapped. The conclusion is that quality control checks are necessary both during and after map compilation. The experience of the CARETS and other land use mapping experiments conducted in the early 1970's has resulted in the development of carefully designed quality-control procedures implemented in the nationwide mapping of land use and land cover currently being carried out by the U.S. Geological Survey.
The climatic index of dune mobility developed by Lancaster (1988) has been applied to a variety of different environments. The index is, however, untested and unverified. We tested the index by comparison of values of the dune mobility index calculated from climate data with rates of sand transport measured at three stations in Arizona and New Mexico over the period 1985 to 1997. Our results show that changes in measured rates of sand transport closely parallel temporal changes in the dune mobility index. The mobility index is, however, a relatively poor predictor of the magnitude of actual sand transport on a year-to-year basis. This discrepancy is probably due to the fact that sand transport rates at these sites are strongly influenced by vegetation cover, the state of which may lag changes in annual precipitation. There is, however, a good relation between the mean annual mobility index and mean annual rates of sand transport. This indicates that the dune mobility index is a valid predictor of the long-term state of the aeolian system and can be used confidently for the purposes for which it was originally intended.
Hyporheic fluxes influence ecological processes across a continuum of timescales. However, few studies have been able to characterize hyporheic fluxes and residence time distributions (RTDs) over timescales of days to years, during which evapotranspiration (ET) and seasonal flood pulses create unsteady forcing. Here we present a data-driven, particle-tracking piston model that characterizes hyporheic fluxes and RTDs based on measured vertical head differences. We used the model to test the relative influence of ET and seasonal flood pulses in the Everglades (FL, USA), in a manner applicable to other low-energy floodplains or broad, shallow streams. We found that over the multiyear timescale, flood pulses that drive relatively deep (∼1 m) flow paths had the dominant influence on hyporheic fluxes and residence times but that ET effects were discernible at shorter timescales (weeks to months) as a break in RTDs. Cumulative RTDs on either side of the break were generally well represented by lognormal functions, except for when ET was strong and none of the standard distributions applied to the shorter timescale. At the monthly timescale, ET increased hyporheic fluxes by 1–2 orders of magnitude; it also decreased 6 year mean residence times by 53–87%. Long, slow flow paths driven by flood pulses increased 6 year hyporheic fluxes by another 1–2 orders of magnitude, to a level comparable to that induced over the short term by shear flow in streams. Results suggest that models of intermediate-timescale processes should include at least two-storage zones with different RTDs, and that supporting field data collection occur over 3–4 years.
A central goal of observing and modeling the earthquake cycle is to forecast when a particular fault may generate an earthquake: a fault late in its earthquake cycle may be more likely to generate an earthquake than a fault early in its earthquake cycle. Models that can explain geodetic observations throughout the entire earthquake cycle may be required to gain a more complete understanding of relevant physics and phenomenology. Previous efforts to develop unified earthquake models for strike-slip faults have largely focused on explaining both preseismic and postseismic geodetic observations available across a few faults in California, Turkey, and Tibet. An alternative approach leverages the global distribution of geodetic and geologic slip rate estimates on strike-slip faults worldwide. Here we use the Kolmogorov-Smirnov test for similarity of distributions to infer, in a statistically rigorous manner, viscoelastic earthquake cycle models that are inconsistent with 15 sets of observations across major strike-slip faults. We reject a large subset of two-layer models incorporating Burgers rheologies at a significance level of α = 0.05 (those with long-term Maxwell viscosities η M <~ 4.0 × 10 19 Pa s and η M >~ 4.6 × 10 20 Pa s) but cannot reject models on the basis of transient Kelvin viscosity η K . Finally, we examine the implications of these results for the predicted earthquake cycle timing of the 15 faults considered and compare these predictions to the geologic and historical record.
Models of dune erosion depend on a set of assumptions that dictate the predicted evolution of dunes throughout the duration of a storm. Lidar observations made before and after Hurricane Sandy at over 800 profiles with diverse dune elevations, widths, and volumes are used to quantify specific dune erosion model parameters including the dune face slope, which controls dune avalanching, and the trajectory of the dune toe, which controls dune migration. Wave‐impact models of dune erosion assume a vertical dune face and erosion of the dune toe along the foreshore beach slope. Observations presented here show that these assumptions are not always valid and require additional testing if these models are to be used to predict coastal vulnerability for decision‐making purposes. Observed dune face slopes steepened by 43% yet did not become vertical faces, and only 50% of the dunes evolved along a trajectory similar to the foreshore beach slope. Observations also indicate that dune crests were lowered during dune erosion. Moreover, analysis showed a correspondence between dune lowering and narrower beaches, smaller dune volumes, and/or longer wave impact.