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USGS1996

Organochlorine contaminants in double-crested cormorants from Green Bay, WI: I. Large-scale extraction and isolation from eggs using semi-permeable membrane dialysis

A 41.3-kg sample of double-crested cormorant ( Phalacrocorax auritus ) egg contents was extracted, yielding over 2 L of egg lipid. The double-crested cormorant (DCC) egg extract, after clean-up and concentration, was intended for use in egg injection studies to determine the embryotoxicity of the organic contaminants found within the eggs. Large-scale dialysis was used as a preliminary treatment to separate the extracted contaminants from the co-extracted sample lipids. The lipid was dialyzed in 80×5 cm semi-permeable membrane devices (SPMDs) in 50-ml aliquants. After the removal of 87 g of cholesterol by freeze-fractionation, the remaining lipid carryover (56 g) was removed by 100 routine gel permeation chromatography (GPC) operations. A 41,293-g sample was thus extracted and purified to the extent that it could easily be placed at a volume of 5 ml, the volume calculated to be necessary for the egg injection study. Analyses were performed comparing contaminant concentrations in the final purified extract to those present in the original egg material, in the extract after dialysis and cholesterol removal, and in the excluded materials. Recoveries of organochlorine pesticides through dialysis and cholesterol ranged from 96% to 135%. Total polychlorinated biphenyls in the final extract were 96% of those measured in the original egg material. Analysis of excluded lipid and cholesterol indicated that 92% of the polychlorinated dibenzo-dioxins and-furans were separated into the final extract.

Archives of Environmental Contamination and Toxico↗

USGS2012

All solution processed organic thin film transistor-backplane with printing technology for electrophoretic display

In this study, solution processes were developed for backplane using an organic thin film transistor (OTFT) as a driving device for an electrophoretic display (EPD) panel. The processes covered not only the key device of OTFTs but also interlayer and pixel electrodes. The various materials and printing processes were adopted to achieve the requirements of devices and functioning layers. The performance of OTFT of the backplane was sufficient to drive EPD sheet by producing a mobility of 0.12 cm2/v x sec and on/off current ratio of 10(5).

Journal of Nanoscience and Nanotechnology↗

USGS2019

sUAS-based remote sensing of river discharge using thermal particle image velocimetry and bathymetric lidar

This paper describes a non-contact methodology for computing river discharge based on data collected from small Unmanned Aerial Systems (sUAS). The approach is complete in that both surface velocity and channel geometry are measured directly under field conditions. The technique does not require introducing artificial tracer particles for computing surface velocity, nor does it rely upon the presence of naturally occurring floating material. Moreover, no prior knowledge of river bathymetry is necessary. Due to the weight of the sensors and limited payload capacities of the commercially available sUAS used in the study, two sUAS were required. The first sUAS included mid-wave thermal infrared and visible cameras. For the field evaluation described herein, a thermal image time series was acquired and a particle image velocimetry (PIV) algorithm used to track the motion of structures expressed at the water surface as small differences in temperature. The ability to detect these thermal features was significant because the water surface lacked floating material (e.g., foam, debris) that could have been detected with a visible camera and used to perform conventional Large-Scale Particle Image Velocimetry (LSPIV). The second sUAS was devoted to measuring bathymetry with a novel scanning polarizing lidar. We collected field measurements along two channel transects to assess the accuracy of the remotely sensed velocities, depths, and discharges. Thermal PIV provided velocities that agreed closely (R^2 = 0.82 and 0.64) with in situ velocity measurements from an acoustic Doppler current profiler (ADCP). Depths inferred from the lidar closely matched those surveyed by wading in the shallower of the two cross sections (R^2 = 0.95) but the agreement was not as strong for the transect with greater depths (R^2 = 0.61). Incremental discharges computed with the remotely sensed velocities and depths were greater than corresponding ADCP measurements by 22% at the first cross section and < 1% at the second.

Colorado↗

USGS2008

Determination of human-health pharmaceuticals in filtered water by chemically modified styrene-divinylbenzene resin-based solid-phase extraction and high-performance liquid chromatography/Mass Spectrometry

In 1999, the Methods Research and Development Program of the U.S. Geological Survey National Water Quality Laboratory began the process of developing a method designed to identify and quantify human-health pharmaceuticals in four filtered water-sample types: reagent water, ground water, surface water minimally affected by human contributions, and surface water that contains a substantial fraction of treated wastewater. Compounds derived from human pharmaceutical and personal-care product use, which enter the environment through wastewater discharge, are a newly emerging area of concern; this method was intended to fulfill the need for a highly sensitive and highly selective means to identify and quantify 14 commonly used human pharmaceuticals in filtered-water samples. The concentrations of 12 pharmaceuticals are reported without qualification; the concentrations of two pharmaceuticals are reported as estimates because long-term reagent-spike sample recoveries fall below acceptance criteria for reporting concentrations without qualification. The method uses a chemically modified styrene-divinylbenzene resin-based solid-phase extraction (SPE) cartridge for analyte isolation and concentration. For analyte detection and quantitation, an instrumental method was developed that used a high-performance liquid chromatography/mass spectrometry (HPLC/MS) system to separate the pharmaceuticals of interest from each other and coextracted material. Immediately following separation, the pharmaceuticals are ionized by electrospray ionization operated in the positive mode, and the positive ions produced are detected, identified, and quantified using a quadrupole mass spectrometer. In this method, 1-liter water samples are first filtered, either in the field or in the laboratory, using a 0.7-micrometer (μm) nominal pore size glass-fiber filter to remove suspended solids. The filtered samples then are passed through cleaned and conditioned SPE cartridges at a rate of about 15 milliliters per minute. Excess water is eliminated from the cartridge sorbent bed by passing air through the cartridges, and the analytes retained on the SPE bed are eluted from the cartridge sequentially, first with methanol, followed by acidified methanol, and combined in collection tubes. This sample extract then is reduced from about 10 milliliters (mL) to about 0.1 mL (or 100 microliters) under a stream of purified nitrogen gas with the collection tubes in a heated (40°C) water bath. The reduced extracts then are fortified with an internal standard solution (when using internal standard quantitation), brought to a final volume of 1 mL with an aqueous ammonium formate buffer solution, and filtered through a 0.2-μm Teflon syringe filter as they are transferred into vials for instrumental analysis. Instrumental analysis by the HPLC/MS procedure permits determination of individual pharmaceutical concentrations from 0.005 to 1.0 microgram per liter, based on the lowest and the highest calibration standards routinely used. The reporting levels for this method are compound dependent, and have been experimentally determined based on the precision of quantitation of compounds from eight fortified organic-free water samples in single-operator experiments. The method detection limits and interim reporting levels for the compounds determined by this method were calculated from recoveries of the pharmaceuticals from reagent-water samples amended at 0.05 microgram per liter, and ranged between 0.0069 and 0.0142 microgram per liter, and 0.015 and 0.10 microgram per liter, respectively. Concentrations for 12 compounds are reported without qualification, and for two compounds are reported as qualified estimates. After initial development, the method was applied to more than 1,800 surface-, ground-, and wastewater samples from 2002 to 2005 and documented in a number of published studies. This research application of the method provided the opportunity to collect a large data set of ambient environmental concentrations and also permitted the collection of an extensive set of reagent blanks and spike quality-control (QC) samples. This multiple-year set of QC samples enabled further evaluation of method performance under multiple operator and multiple instrument conditions typical of routine laboratory operation. These results are an important part of the entire data set contained in this report because they document method performance over an extended time. Because sample matrix can substantially affect method performance, inclusion of environmental matrix-spike samples is required as a routine component of study plan quality control. Method performance has been measured by long-term tracking of observed recoveries from fortified organic-free water samples processed with environmental samples (laboratory reagent spikes), as well as by observed recoveries from multiple fortified environmental water samples. The fortified environmental samples included surface water, wastewater effluent-dominated surface water, and ground water, fortified at two environmentally relevant concentrations and corrected for ambient environmental concentrations. Because the responses of individual pharmaceuticals vary as a function of proton affinity, the ionization efficiency, and thus relative response, of each pharmaceutical, the quality-control surrogate compounds, and the quantitation internal standard can be suppressed or enhanced by the presence of the sample matrix. As a result, several quality-control sample types are required to properly interpret the ambient environmental concentrations of pharmaceuticals in aqueous samples. The quality-control sample types and results include laboratory reagent spikes and laboratory reagent blanks to provide insight into the performance of the method in the absence of a sample matrix, and matrix-spike recovery samples and replicate environmental samples, collected from representative sample matrix types within the aquatic system under study.

Techniques and Methods↗

USGS2015

Summary of oceanographic and water-quality measurements in Rachel Carson National Wildlife Refuge, Wells, Maine, in 2013

Suspended-sediment transport is a critical element controlling the geomorphology of tidal wetland complexes. Wetlands rely on organic material and inorganic sediment deposition to maintain their elevation relative to sea level. The U.S. Geological Survey performed observational deployments to measure suspended-sediment concentration and water flow rates in the tidal channels of the wetlands in the Rachel Carson National Wildlife Refuge in Wells, Maine. The objective was to characterize the sediment-transport mechanisms that contribute to the net sediment budget of the wetland complex. We deployed a meteorological tower, optical turbidity sensors, and acoustic velocity meters at sites on Stephens Brook and the Ogunquit River between March 27 and December 9, 2013. This report presents the time-series oceanographic and atmospheric data collected during those field studies. The oceanographic parameters include water velocity, depth, turbidity, salinity, temperature, and pH. The atmospheric parameters include wind direction, speed, and gust; air temperature; air pressure; relative humidity; short wave radiation; and photosynthetically active radiation.

Maine↗

USGS1972

Significance of ground-water chemistry in performance of North Sahara Tube wells in Algeria and Tunisia

Nine ground-water samples from the principal shallow and deep North Sahara aquifers of Algeria and Tunisia were examined to determine the relation of their chemical composition to corrosion and mineral encrustation thought to be contributing to observed decline in well capacities within a UNESCO/UNDP Special Fund Project area. Although the shallow and deep waters differ significantly in certain quality factors, all are sulfochloride types with corrosion potentials ranging from moderate to extreme. None appear to be sufficiently supersaturated with troublesome mineral species to cause rapid or severe encrustation of filter pipes or other well parts. However, calcium carbonate encrustation of deep-well cooling towers and related irrigation pipes can be expected because of loss of carbon dioxide and water during evaporative cooling. Corrosion products, particularly iron sulfide, can be expected to deposit in wells producing waters from the deep aquifers. This could reduce filterpipe openings and increase casing roughness sufficiently to cause significant reduction in well capacity. It seems likely, however, that normal pressure reduction due to exploitation of the artesian systems is a more important control of well performance. If troublesome corrosion and related encrustation are confirmed by downhole inspection, use of corrosion-resisting materials, such as fiber-glass casing and saw-slotted filter pipe (shallow wells only), or stainless-steel screen, will minimize the effects of the waters represented by these samples. A combination of corrosion-resisting stainless steel filter pipe electrically insulated from the casing with a nonconductive spacer and cathodic protection will minimize external corrosion of steel casing, if this is found to be a problem. However, such installations are difficult to make in very deep wells and difficult to control in remote areas. Both the shallow waters and the deep waters examined in this study will tend to cause soil salinization because their salt contents are relatively high, and both have sodium absorption ratios which are unfavorable to sodium-sensitive soils and vegetation. Proper drainage and soil treatment are the only means of overcoming these problems during irrigation.

Water Supply Paper↗

USGS2012

Pre- and post-remediation characterization of acid-generating fluvial tailings material

The upper Arkansas River south of Leadville, Colorado, USA, contains deposits of fluvial tailings from historical mining operations in the Leadville area. These deposits are potential non-point sources of acid and metal contamination to surface- and groundwater systems. We are investigating a site that recently underwent in situ remediation treatment with lime, fertilizer, and compost. Pre- and post-remediation fluvial tailings material was collected from a variety of depths to examine changes in mineralogy, acid generation, and extractable nutrients. Results indicate sufficient nutrient availability in the post-remediation near-surface material, but pyrite and acid generation persist below the depth of lime and fertilizer addition. Mineralogical characterization performed using semi-quantitative X-ray diffraction and quantitative SEM-based micro-mineralogy (Mineral Liberation Analysis, MLA) reveal formation of gypsum, jarosite, and complex coatings surrounding mineral grains in post-remediation samples.

Colorado↗

USGS1981

Geological considerations in hazardous waste disposal

Present regulations assume that long-term isolation of hazardous wastes - including toxic chemical, biological, radioactive, flammable and explosive wastes - may be effected by disposal in landfills that have liners of very low hydraulic conductivity. In reality, total isolation of wastes in humid areas is not possible; some migration of leachate from wastes buried in the gound will always occur. Regulations should provide performance standards applicable on a site-by-site basis rather than rigid criteria for site selection and design. The performance standards should take into account several factors: (1) the categories, segregation, degradation and toxicity of the wastes; (2) the site hydrogeology, which governs the direction and rate of contaminant transport; (3) the attenuation of contaminants by geochemical interactions with geologic materials; and (4) the release rate of unattenuated pollutants to surface or groundwater. An adequate monitoring system is essential. The system should both test the extent to which the operation of the site meets performance standards and provide sufficient warning of pollution problems to allow implementation of remedial measures. In recent years there has been a trend away from numerous, small disposal sites toward fewer and larger sites. The size of a disposal site should be based on the attenuation capacity of the geologic material, which has a finite, though generally not well-defined, limit. For slowly degradable wastes, engineered sites with leachate-collection systems appear to be only a temporary solution since the leachate collected will also require final disposal.

Journal of Hydrology↗

USGS2010

Examination of Libby, Montana, Fill Material for Background Levels of Amphibole from the Rainy Creek Complex Using Scanning Electron Microscopy and X-Ray Microanalysis

Natural background levels of Libby-type amphibole in the sediment of the Libby valley in Montana have not, up to this point, been determined. The purpose of this report is to provide the preliminary findings of a study designed by both the U.S. Geological Survey and the U.S. Environmental Protection Agency and performed by the U.S. Geological Survey. The study worked to constrain the natural background levels of fibrous amphiboles potentially derived from the nearby Rainy Creek Complex. The material selected for this study was sampled from three localities, two of which are active open-pit sand and gravel mines. Seventy samples were collected in total and examined using a scanning electron microscope equipped with an energy dispersive x-ray spectrometer. All samples contained varying amounts of feldspars, ilmenite, magnetite, quartz, clay minerals, pyroxene minerals, and non-fibrous amphiboles such as tremolite, actinolite, and magnesiohornblende. Of the 70 samples collected, only three had detectable levels of fibrous amphiboles compatible with those found in the rainy creek complex. The maximum concentration, identified here, of the amphiboles potentially from the Rainy Creek Complex is 0.083 percent by weight.

Open-File Report↗

USGS2016

The rise and fall of infectious disease in a warmer world

Now-outdated estimates proposed that climate change should have increased the number of people at risk of malaria, yet malaria and several other infectious diseases have declined. Although some diseases have increased as the climate has warmed, evidence for widespread climate-driven disease expansion has not materialized, despite increased research attention. Biological responses to warming depend on the non-linear relationships between physiological performance and temperature, called the thermal response curve. This leads performance to rise and fall with temperature. Under climate change, host species and their associated parasites face extinction if they cannot either thermoregulate or adapt by shifting phenology or geographic range. Climate change might also affect disease transmission through increases or decreases in host susceptibility and infective stage (and vector) production, longevity, and pathology. Many other factors drive disease transmission, especially economics, and some change in time along with temperature, making it hard to distinguish whether temperature drives disease or just correlates with disease drivers. Although it is difficult to predict how climate change will affect infectious disease, an ecological approach can help meet the challenge.

F1000 Research↗

USGS2016

Volcano deformation source parameters estimated from InSAR: Sensitivities to uncertainties in seismic tomography

The eruption cycle of a volcano is controlled in part by the upward migration of magma. The characteristics of the magma flux produce a deformation signature at the Earth's surface. Inverse analyses use geodetic data to estimate strategic controlling parameters that describe the position and pressurization of a magma chamber at depth. The specific distribution of material properties controls how observed surface deformation translates to source parameter estimates. Seismic tomography models describe the spatial distributions of material properties that are necessary for accurate models of volcano deformation. This study investigates how uncertainties in seismic tomography models propagate into variations in the estimates of volcano deformation source parameters inverted from geodetic data. We conduct finite element model-based nonlinear inverse analyses of interferometric synthetic aperture radar (InSAR) data for Okmok volcano, Alaska, as an example. We then analyze the estimated parameters and their uncertainties to characterize the magma chamber. Analyses are performed separately for models simulating a pressurized chamber embedded in a homogeneous domain as well as for a domain having a heterogeneous distribution of material properties according to seismic tomography. The estimated depth of the source is sensitive to the distribution of material properties. The estimated depths for the homogeneous and heterogeneous domains are 2666 ± 42 and 3527 ± 56 m below mean sea level, respectively (99% confidence). A Monte Carlo analysis indicates that uncertainties of the seismic tomography cannot account for this discrepancy at the 99% confidence level. Accounting for the spatial distribution of elastic properties according to seismic tomography significantly improves the fit of the deformation model predictions and significantly influences estimates for parameters that describe the location of a pressurized magma chamber.

Journal of Geophysical Research B: Solid Earth↗

USGS1987

Physical properties of the surface materials at the Viking landing sites on Mars

This report summarizes the results of the Physical Properties Investigation of the Viking '75 Project, activities of the surface samplers, and relevant results from other investigations. The two Viking Landers operated for nearly four martian years after landing on July 20 (Lander 1) and Sept. 3 (Lander 2), 1976; Lander 1 acquired its last pictures on or about Nov. 5, 1982. Lander 1 rests on a smooth, cratered plain at the west edge of Chryse Planitia (22.5 ? N, 48.0? W), and Lander 2 rests 200 km west of the crater Mie in Utopia Planitia (48.0? N, 225.7? W). Lander 1 views showed that dune-like deposits of drift material were superposed on rock-strewn surfaces. Soil-like material from the rock-strewn areas was called blocky material. Lander 2 views also showed a rock-strewn surface. Polygonal to irregular features, etched by the wind, revealed crusty to cloddy material among rocks. Both landers descended to the surface along nearly vertical trajectories. Velocities at touchdown were about 2 m/s for both landers. Footpad 2 of Lander 1 penetrated drift material 0.165 m, and footpad 3 penetrated blocky material 0.036 m. The two visible footpads of Lander 2 struck rocks. Erosion by exhausts from the forward engines produced craters with rims of mixed fine-grained material and platy to equidimensional clods, crusts, and fragments. Comparison of engine-exhaust erosion on Mars with terrestrial data suggested that drift material behaved like a weakly cohesive material with a grain size less than 3-9 /-lm. Although not sand, blocky and crusty to cloddy materials eroded like sand-with grain sizes of 0.01 or 0.2 cm. The surface samplers accomplished an impressive number of tasks. All experiments that required samples received samples. Deep holes, as much as 0.22 m deep, were excavated by both landers. Lander 2 successfully pushed rocks and collected samples from areas originally beneath the rocks. Tasks specifically accomplished for the Physical Properties Investigation include: (1) acquiring motor-current data while excavating trenches, (2) performing surface-bearing tests, (3) performing backhoe touchdowns, (4) attempting to chip or scratch rocks, (5) comminuting samples, (6) measuring subsurface diurnal temperatures, and (7) constructing conical piles of materials on and among rocks. Sample trenches in the three major types of soil-like materials were different from one another. Trenches in drift material, which were typically 0.06 m deep, had steep walls along much of their lengths, lumpy tailings and floors, and smooth domed surfaces with sparse fine fractures around their tips. Trenches in blocky material, which were typically 0.03-0.04 m deep, had steep walls near their tips, and surfaces around their tips were displaced upward and some appeared blocky. Trenches in crusty to cloddy material, which were typically 0.04-0.05 m deep, had steep and often irregular slopes near their tips, clods and slabs of crust in their tailings, and disrupted areas around their tips composed of mixed fine-grained material and slabs of crust or thick polygonal clods that had been displaced upwards. Data acquired during landing, trenching, surface-bearing tests, backhoe touchdowns, and from other science experiments were used to determine the mechanical properties of drift, blocky, and crusty to cloddy materials. Drift material appeared to be very fine grained, with local planes of weakness; in general, the drift material was consistent with a material having an angle of internal friction about 18?, a cohesion ranging from 0.7 to 3.0 kPa, and a bulk density of 1,200 kg/m 3 . Blocky material was consistent with a material having an angle of internal friction about 30?, cohesions from 1.5 to 16 kPa, and a bulk density of 1,600 kg/m 3 . Crusty to cloddy material had variable properties. For chiefly crusty to cloddy material, angles of internal friction were about 35 ? , and cohesions were from 0.5 to 5.2 kPa. For mixed fines and crusts, a

Professional Paper↗

USGS2013

Performance of human fecal anaerobe-associated PCR-based assays in a multi-laboratory method evaluation study

A number of PCR-based methods for detecting human fecal material in environmental waters have been developed over the past decade, but these methods have rarely received independent comparative testing in large multi-laboratory studies. Here, we evaluated ten of these methods (BacH, BacHum-UCD, Bacteroides thetaiotaomicron (BtH), BsteriF1, gyrB, HF183 endpoint, HF183 SYBR, HF183 Taqman®, HumM2, and Methanobrevibacter smithii nifH (Mnif)) using 64 blind samples prepared in one laboratory. The blind samples contained either one or two fecal sources from human, wastewater or non-human sources. The assay results were assessed for presence/absence of the human markers and also quantitatively while varying the following: 1) classification of samples that were detected but not quantifiable (DNQ) as positive or negative; 2) reference fecal sample concentration unit of measure (such as culturable indicator bacteria, wet mass, total DNA, etc); and 3) human fecal source type (stool, sewage or septage). Assay performance using presence/absence metrics was found to depend on the classification of DNQ samples. The assays that performed best quantitatively varied based on the fecal concentration unit of measure and laboratory protocol. All methods were consistently more sensitive to human stools compared to sewage or septage in both the presence/absence and quantitative analysis. Overall, HF183 Taqman® was found to be the most effective marker of human fecal contamination in this California-based study.

Water Research↗

USGS2009

Laboratory evaluation of an OTT acoustic digital current meter and a SonTek Laboratory acoustic Doppler velocimeter

Recently, an acoustic current meter known as the OTT * acoustic digital current meter (ADC) was introduced as an alternative instrument for stream gaging measurements. The Bureau of Reclamation and the U.S. Geological Survey collaborated on a side- by-side evaluation of the ADC and a SonTek/YSI acoustic Doppler velocimeter (ADV). Measurements were carried out in a laboratory flume to evaluate the performance characteristics of the ADC under a range of flow and boundary conditions. The flume contained a physical model of a mountain river with a diversion dam and variety of bed materials ranging from smooth mortar to a cobble bed. The instruments were installed on a trolley system that allowed them to be easily moved within the flume while maintaining a consistent probe orientation. More than 50 comparison measurements were made in an effort to verify the manufacturer’s performance specifications and to evaluate potential boundary disturbance for near-bed and vertical boundary measurements. Data and results from this evaluation are presented and discussed.

Conference Paper↗

USGS2019

Hysteretic response of solutes and turbidity at the event scale across forested tropical montane watersheds

Concentration-discharge relationships are a key tool for understanding the sourcing and transport of material from watersheds to fluvial networks. Storm events in particular provide insight into variability in the sources of solutes and sediment within watersheds, and the hydrologic pathways that connect hillslope to stream channel. Here we examine high-frequency sensor-based specific conductance and turbidity data from multiple storm events across two watersheds (Quebrada Sonadora and Rio Icacos) with different lithology in the Luquillo Mountains of Puerto Rico, a forested tropical ecosystem. Our analyses include Hurricane Maria, a category 5 hurricane. To analyze hysteresis, we used a recently developed set of metrics to describe and quantify storm events including the hysteresis index (HI), which describes the directionality of hysteresis loops, and the flushing index (FI), which can be used to infer whether the mobilization of material is source or transport limited. We also examine the role of antecedent discharge to predict hysteretic behavior during storms. Overall, specific conductance and turbidity showed contrasting responses to storms. The hysteretic behavior of specific conductance was very similar across sites, displaying clockwise hysteresis and a negative flushing index indicating proximal sources of solutes and consistent source limitation. In contrast, the directionality of turbidity hysteresis was significantly different between watersheds, although both had strong flushing behavior indicative of transport limitation. Overall, models that included antecedent discharge did not perform any better than models with peak discharge alone, suggesting that the magnitude and trajectory of an individual event was the strongest driver of material flux and hysteretic behavior. Hurricane Maria produced unique hysteresis metrics within both watersheds, indicating a distinctive response to this major hydrological event. The similarity in response of specific conductance to storms suggests that solute sources and pathways are similar in the two watersheds. The divergence in behavior for turbidity suggests that sources and pathways of particulate matter vary between the two watersheds. The use of high-frequency sensor data allows the quantification of storm events while index-based metrics of hysteresis allow for the direct comparison of complex storm events across a heterogeneous landscape and variable flow conditions.

Luquillo Mountains↗

USGS2021

Particle tracer analysis for submerged berm placement of dredged material near South Padre Island, Texas

The fate of unconfined dredged sediment placed as a submerged “feeder” berm in the nearshore region of South Padre Island (SPI), Texas, was investigated through a particle tracer study over the duration of 15 months. Unconfined sediment feeder systems can be a desirable alternative to traditional direct beach placement of nourishment material because the feeder systems are less intrusive to the beach environment and often less expensive. Placing sediment as close to the active beach profile, as practicable, and relying on natural nearshore processes to slowly distribute the sediment to the beach can keep a finite resource within the littoral zone. One challenge with this indirect approach is predicting the short- and long-term effects on the coastal system and shoreline in light of the complex nearshore dynamics involved. This study aims at elucidating sediment transport pathways at SPI after tracer release over the feeder berm via assessment of tracer particle counts obtained from nine sediment sampling campaigns (950 surface-sediment grab samples) between August 2018 and November 2019, covering a grid of 60 seabed and 50 dry beach locations. Tracer counts were performed in the laboratory making use of the fluorescent and ferromagnetic properties of the engineered particles to separate them from other sediment material. Results indicate that although the highest tracer counts remained near the initial release site of the feeder berm during the duration of the study, appreciable amounts of tracer moved throughout the study region. Even though fluctuations of tracer migration were observed, the most prominent appearance of tracer particles outside the initial placement site occurred south and immediately west of it, indicating net alongshore and onshore transport in those directions. Relatively, few tracer particles were found on the dry beach, indicating appreciable deposition of feeder material there may take years rather than months.

Texas↗

USGS2013

Instrumental neutron activation analysis data for cloud-water particulate samples, Mount Bamboo, Taiwan

Cloud water was sampled on Mount Bamboo in northern Taiwan during March 22-24, 2002. Cloud-water samples were filtered using 0.45-micron filters to remove particulate material from the water samples. Filtered particulates were analyzed by instrumental neutron activation analysis (INAA) at the U.S. Geological Survey National Reactor Facility in Denver, Colorado, in February 2012. INAA elemental composition data for the particulate materials are presented. These data complement analyses of the aqueous portion of the cloud-water samples, which were performed earlier by the Department of Atmospheric Sciences, National Central University, Taiwan. The data are intended for evaluation of atmospheric transport processes and air-pollution sources in Southeast Asia.

Mount Bamboo↗

USGS2013

GEM Building Taxonomy (Version 2.0)

This report documents the development and applications of the Building Taxonomy for the Global Earthquake Model (GEM). The purpose of the GEM Building Taxonomy is to describe and classify buildings in a uniform manner as a key step towards assessing their seismic risk, Criteria for development of the GEM Building Taxonomy were that the Taxonomy be relevant to seismic performance of different construction types; be comprehensive yet simple; be collapsible; adhere to principles that are familiar to the range of users; and ultimately be extensible to non-buildings and other hazards. The taxonomy was developed in conjunction with other GEM researchers and builds on the knowledge base from other taxonomies, including the EERI and IAEE World Housing Encyclopedia, PAGER-STR, and HAZUS. The taxonomy is organized as a series of expandable tables, which contain information pertaining to various building attributes. Each attribute describes a specific characteristic of an individual building or a class of buildings that could potentially affect their seismic performance. The following 13 attributes have been included in the GEM Building Taxonomy Version 2.0 (v2.0): 1.) direction, 2.)material of the lateral load-resisting system, 3.) lateral load-resisting system, 4.) height, 5.) date of construction of retrofit, 6.) occupancy, 7.) building position within a block, 8.) shape of the building plan, 9.) structural irregularity, 10.) exterior walls, 11.) roof, 12.) floor, 13.) foundation system. The report illustrates the pratical use of the GEM Building Taxonomy by discussing example case studies, in which the building-specific characteristics are mapped directly using GEM taxonomic attributes and the corresponding taxonomic string is constructed for that building, with "/" slash marks separating attributes. For example, for the building shown to the right, the GEM Taxonomy string is: DX 1 /MUR+CLBRS+MOCL 2 /LWAL 3 / DY/MUR+CLBRS+MOCL/LWAL/YPRE:1939 4 /HEX:2 5 /RES 6 / 7 / 8 /IRRE 9 /10/RSH3+RWO2 11 /FW 12 / 13 / which can be read as (1) Direction = [DX or DY] (the building has the same lateral load-resisting system in both directions); (2) Material = [Unreinforced Masonry + solid fired clay bricks + cement: lime mortar]; (3) Lateral Load-Resisting System = [Wall]; (4) Date of construction = [pre-1939]; (5) Heaight = [exactly 2 storeys]; (6) Occupancy = [residential, unknown type]; (7) Building Position = [unknown = no entry]; (8) Shape of building plan = [unknown = no entry]; (9) Structural irregularity = [regular]; (10) Exterior walls = [unknown = no entry]; (11) Roof = [Shape: pitched and hipped, Roof covering: clay tiles, Roof system material: wood, Roof system type: wood trusses]; (12) Floor = [Floor system: Wood, unknown]; (13) Foundation = [unknown = no entry]. Mapping of GEM Building Taxonomy to selected taxonomies is included in the report -- for example, the above building would be referenced by previous structural taxonomies as: PAGER-STR as UFB or UFB4, by the World Housing Encyclopedia as 7 or 8 and by the European Macroseismic Scale (98) as M5. The Building Taxonomy data model is highly flexible and has been incorporated within a relational database architecture. Due to its ability to represent building typologies using a shorthand form, it is also possible to use the taxonomy for non-database applications, and we discuss possible application of adaptation for Building Information Modelling (BIM) systems, and for the insurance industry. The GEM Building Taxonomy was independently evaluated and tested by the Earthquake Engineering Research Institute (EERI), which received 217 TaxT reports from 49 countries, representing a wide range of building typologies, including single and multi-storey buildings, reinforced and unreinforced masonry, confined masonry, concrete, steel, wood, and earthern buildings used for residential, commercial, industrial, and educational occupancy. Based on these submissions and other feedback, the EERI team validated that the GEM Building Taxonomy is highly functional, robust and able to describe different buildings around the world. The GEM Building Taxonomy is accompanied by supplementary resources. All terms have been explained in a companion online Glossary, which provides both text and graphic descriptions. The Taxonomy is accompanied by TaxT, a computer application that enables a user record information about a building or a building typology using the attributes of the GEM Building Taxonomy v2.0. TaxT can generate a taxonomy string and enable a user to generate a report in PDF format which summarizes the attribute values (s)he has chosen as representative of the building typology under consideration. The report concludes with recommendations for future development of the GEM Building Taxonomy. Appendices provide the detailed GEM Building Taxonomy tables and additional resource, as well as mappings to other taxonomies.

GEM Technical Report↗