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FishVis, A regional decision support tool for identifying vulnerabilities of riverine habitat and fishes to climate change in the Great Lakes Region

Climate change is expected to alter the distributions and community composition of stream fishes in the Great Lakes region in the 21st century, in part as a result of altered hydrological systems (stream temperature, streamflow, and habitat). Resource managers need information and tools to understand where fish species and stream habitats are expected to change under future conditions. Fish sample collections and environmental variables from multiple sources across the United States Great Lakes Basin were integrated and used to develop empirical models to predict fish species occurrence under present-day climate conditions. Random Forests models were used to predict the probability of occurrence of 13 lotic fish species within each stream reach in the study area. Downscaled climate data from general circulation models were integrated with the fish species occurrence models to project fish species occurrence under future climate conditions. The 13 fish species represented three ecological guilds associated with water temperature (cold, cool, and warm), and the species were distributed in streams across the Great Lakes region. Vulnerability (loss of species) and opportunity (gain of species) scores were calculated for all stream reaches by evaluating changes in fish species occurrence from present-day to future climate conditions. The 13 fish species included 4 cold-water species, 5 cool-water species, and 4 warm-water species. Presently, the 4 cold-water species occupy from 15 percent (55,000 kilometers [km]) to 35 percent (130,000 km) of the total stream length (369,215 km) across the study area; the 5 cool-water species, from 9 percent (33,000 km) to 58 percent (215,000 km); and the 4 warm-water species, from 9 percent (33,000 km) to 38 percent (141,000 km). Fish models linked to projections from 13 downscaled climate models projected that in the mid to late 21st century (2046–65 and 2081–2100, respectively) habitats suitable for all 4 cold-water species and 4 of 5 cool-water species under present-day conditions will decline as much as 86 percent and as little as 33 percent, and habitats suitable for all 4 warm-water species will increase as much as 33 percent and as little as 7 percent. This report documents the approach and data used to predict and project fish species occurrence under present-day and future climate conditions for 13 lotic fish species in the United States Great Lakes Basin. A Web-based decision support mapping application termed “FishVis” was developed to provide a means to integrate, visualize, query, and download the results of these projected climate-driven responses and help inform conservation planning efforts within the region.

Great Lakes Region↗

Flood-inundation maps for Dardenne Creek in St. Charles County, Missouri, 2019

Digital flood-inundation maps for a 9.9-mile reach of Dardenne Creek, St. Charles County, Missouri, were created by the U.S. Geological Survey (USGS), in cooperation with the Missouri Department of Transportation, St. Charles County, and the Cities of O’Fallon and St. Peters, Mo. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Program website at https://www.usgs.gov/​mission-​areas/​water-​resources/​science/​flood-​inundation-​mapping-​fim-​program , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgages 05514860 Dardenne Creek at Old Town St. Peters, Mo., and 05587450 Mississippi River at Grafton, Illinois. Near-real-time stages at these streamgages may be obtained from the USGS National Water Information System at https://doi.org/​10.5066/​F7P55KJN or the National Weather Service Advanced Hydrologic Prediction Service at https://water.weather.gov/ ahps2/ hydrograph.php? wfo= lsx&gage= drcm7 and https://water.weather.gov/ ahps2/ hydrograph.php? wfo= lsx&gage= grfi2 , which also forecasts flood hydrographs at these sites (sites DRCM7 and GRFI2). Flood profiles were computed for the Dardenne Creek stream reach by means of a one-dimensional model for simulating water-surface profiles with steady-state flow computations. The model was calibrated by using the current stage-streamflow relation at the USGS streamgages 05514840 Dardenne Creek at O’Fallon, Mo., and 05514860 Dardenne Creek at Old Town St. Peters, Mo., and the documented high-water marks from the flood of December 2015. The hydraulic model was then used to compute 17 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 16 ft, or near bankfull, to 32 ft at the reference streamgage 05514860. Stages in the lower Dardenne Creek can be affected by backwater from the Mississippi River; therefore, several sets of water-surface profiles were developed representing the extent of varying levels of backwater as referenced to the USGS streamgage 05587450 on the Mississippi River at Grafton, Ill. The upper stage for each map library exceeds the stage corresponding to the estimated 0.2-percent annual exceedance probability flood (500-year recurrence interval flood) at the streamgage location. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.26-ft vertical accuracy and 0.71-ft horizontal resolution) to delineate the area flooded at each water level. The availability of these maps, along with real-time information regarding current stage from the USGS streamgage and forecasted high-flow stages from the National Weather Service, will provide emergency management personnel and residents with information that is critical for flood mitigation, preparedness and planning, flood-response activities such as evacuations and road closures, and postflood recovery efforts.

Missouri↗

Flood-Inundation Maps of the Current and Jacks Fork Rivers including the Ozark National Scenic Riverways, Southeast Missouri, 2023

Digital flood-inundation maps for a 131.8-mile reach of the Current River and a 44.6-mile reach of the Jacks Fork River, in southeast Missouri, were created by the U.S. Geological Survey (USGS) in cooperation with the Ozark Foothills Regional Planning Commission and the South Central Ozark Council of Governments. The maps also encompass the 134 miles of the Current and Jacks Fork Rivers within the Ozark National Scenic Riverways, which is the first national park area to protect a river system. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Program website at https://water.usgs.gov/osw/flood_inundation/ , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (hereafter referred to as “stages”) at eight reference USGS streamgages—five on the Current River (USGS station numbers 07064440, 07064533, 07066510, 07067000, and 07068000) and three on the Jacks Fork River (USGS station numbers 07065200, 07065495, and 07066000). Near-real-time stages at these streamgages may be obtained from the USGS National Water Information System at https://doi.org/10.5066/F7P55KJN or the National Weather Service National Water Prediction Service at http://water.noaa.gov/ , which also forecasts flood hydrographs at four of these sites (USGS station numbers 07067000, 07068000, 07065495, and 07066000). Flood profiles were computed for seven of the eight map reaches by means of two-dimensional hydraulic models and the remaining reach by a one-dimensional hydraulic model. The models were calibrated by using stage-streamflow relations or streamflow measurements at the USGS streamgages and from high-flow stage measurements from water-level loggers distributed throughout the reaches. The hydraulic models were used to compute water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datums. The profile stages ranged from the National Weather Service “action stage” or near bankfull, to a stage exceeding the highest recorded water level at each streamgage. The simulated water-surface profiles were then combined with a digital elevation model (derived from light detection and ranging data having a nonvegetated vertical accuracy of a maximum 10-centimeter root mean square error) to delineate the area flooded at each water level and the associated water depths. The availability of these maps, along with information regarding current stage from the USGS streamgage and forecasted high-flow stages from the National Weather Service, will provide emergency management personnel, resource managers, and residents with information that is critical for flood-response activities such as evacuations and road closures, as well as for postflood recovery efforts.

Missouri↗

Potentiometric Surfaces and Water-Level Trends in the Cockfield (Upper Claiborne) and Wilcox (Lower Wilcox) Aquifers of Southern and Northeastern Arkansas, 2009

Eocene-age sand beds near the base of the Cockfield Formation of Claiborne Group constitute the aquifer known locally as the Cockfield aquifer. Upper-Paleocene age sand beds within the lower parts of the Wilcox Group constitute the aquifer known locally as the Wilcox aquifer. In 2005, reported water withdrawals from the Cockfield aquifer in Arkansas totaled 16.1 million gallons per day, while reported water withdrawals from the Wilcox aquifer in Arkansas totaled 27.0 million gallons per day. Major withdrawals from these units were for industrial and public water supplies with lesser but locally important withdrawals for commercial, domestic, and agricultural uses. During February 2009, 56 water-level measurements were made in wells completed in the Cockfield aquifer and 57 water-level measurements were made in wells completed in the Wilcox aquifer. The results from the 2009 water-level measurements are presented in potentiometric-surface maps and in combination with previous water-level measurements. Trends in water-level change over time within the two aquifers are investigated using water-level difference maps and well hydrographs. Water-level difference maps were constructed for each aquifer using the difference between depth to water measurements made in 2003 to 2009. Well hydrographs for each aquifer were constructed for wells with 20 or more years of historical water-level data. The hydrographs were evaluated individually using linear regression to calculate the annual rise or decline in water levels, and by aggregating the regression results by county and statistically summarizing for the range, mean, and median water-level change in each county. The 2009 potentiometric surface of the Cockfield aquifer map indicates the regional direction of groundwater flow generally towards the east and southeast, except in two areas of intense groundwater withdrawals that have developed into cones of depression. The lowest water-level altitude measured was 43 feet and the highest water-level altitude measured was 351 feet. A water-level difference map was constructed from 54 wells completed in the Cockfield aquifer within Arkansas. The largest rise in water level was 14.9 feet and the largest decline was 27.4 feet. Seven wells had a rise in water level, and the remaining 47 wells had a decline in water level. Hydrographs for 33 wells completed in the Cockfield aquifer were developed. Hydrographs indicate water-level changes in individual wells ranged from rises of 0.33 feet per year to declines of 1.21 feet per year over the 20-year period (1990-2009). County summaries of the linear regression analysis indicate Cleveland and Columbia Counties have mean annual rises. Arkansas, Ashley, Bradley, Calhoun, Chicot, Desha, Drew, Lincoln, and Union Counties have mean annual declines. The potentiometric surface for the Wilcox aquifer is presented using two maps, one for a southern area and another for a northeastern area, because of the absence of water-level data in the central part of the State. The direction of groundwater flow in the southern area is generally the east, except around two cones of depression and around two mounds of elevated water levels. Water-level altitudes in the southern area range from 147 feet to 400 feet. The direction of groundwater flow in the northeastern area is generally to the south and southeast except in an area of intense groundwater withdrawals that has altered the flow to a westerly direction. Two water-level difference maps were constructed using water-level altitudes measured in 2003 to 2009 from 53 wells completed in the Wilcox aquifer within southern and northeastern Arkansas. In the southern area the largest rise in water level was 16.0 feet and the largest decline was 17.7 feet. Eight wells in the southern area had rising water levels and the remaining five wells had declining water levels. In the northeastern area, the largest rise in water level was 1.3 feet and the larg

Scientific Investigations Report↗

Hydrologic and hydraulic analyses of selected streams near the city of Rittman in Wayne and Medina Counties, Ohio

The U.S. Geological Survey, in cooperation with the Muskingum Watershed Conservancy District and the city of Rittman, Ohio, did a study to provide data to update and expand parts of two Federal Emergency Management Agency Flood Insurance Studies. The study consisted of hydrologic and hydraulic analyses for selected reaches of four streams (Chippewa Creek, Little Chippewa Creek, Styx River, and the unnamed tributary to Styx River) near the city of Rittman in Wayne and Medina Counties, Ohio. The study covered 36.2 miles of stream reaches. Instantaneous peak streamflows for floods with 10-, 4-, 2-, 1-, and 0.2-percent and 1-percent plus annual exceedance probabilities were estimated using historical streamflow data from three U.S. Geological Survey streamgages and regional flood-frequency regression equations. The flood-frequency estimates were then used in a Hydrologic Engineering Center River Analysis System step-backwater model to determine water-surface profiles; flood-inundation boundaries for the 10-, 4-, 2-, 1-, and 0.2-percent and 1-percent plus annual exceedance probabilities; and a regulatory floodway for the study reaches. Model inputs included cross sections derived from a digital elevation model supplemented with field surveys of open-channel cross sections and hydraulic structures, field estimates of Manning’s roughness values, and flood estimates determined from regional regression equations and historical streamflow data. Flood-inundation boundaries were mapped for each stream reach for the 1- and 0.2-percent annual exceedance probability floods and a regulatory floodway. All data used in the creation of the flood-inundation boundaries are available through a U.S. Geological Survey data release (Ostheimer, 2021) and will be submitted to the Federal Emergency Management Agency for inclusion in updated Flood Insurance Studies for Wayne and Medina Counties.

Ohio↗

Using public participatory geographic information systems (PPGIS) to explore uses and values for Mojave Trails National Monument, California

Many people ascribe a variety of values to public lands and waters, but some values are more difficult to assess and quantify than others. Public participatory geographic information systems (PPGIS) are tools that have been used to help quantify and map the public’s diverse values for a landscape. This work describes the first known Office of Management and Budget–approved use of PPGIS by a Department of the Interior bureau. The U.S. Geological Survey developed an internet-based application to aid in gathering PPGIS data, called Values Mapping for Planning in Regional Ecosystems (VaMPIRE). Further, this work describes the first pilot of the VaMPIRE application in coordination with the Bureau of Land Management to collect spatial data and other survey data regarding the public’s uses of and values for locations within Mojave Trails National Monument. We emailed the link to the VaMPIRE application to an interested party email list in 2024 with 207 valid emails and received 74 responses; we also received 47 responses from members of an off-roading social media group. Of the list of 16 value options, recreation was the most popular value for the monument, followed by wilderness and inspirational. Over 1,000 points were placed throughout the monument, indicating locations people use or value, with the locations spread throughout the entire monument. Additionally, most survey respondents stated their ability to receive benefits in locations they mapped would not change in response to a hypothetical scenario related to recreational facility development. This report describes exploratory results from the first use of the VaMPIRE tool in Mojave Trails National Monument and includes reflections on how the process went and considerations for future use of VaMPIRE.

California↗

Reconstructing the Quaternary depositional history using geologic mapping and three-dimensional modeling of the subsurface near Fort Morgan, northeastern Colorado

Centered on Fort Morgan, Colorado, this study is intended to build from previous work by adding a three-dimensional (3D) view of the subsurface to better understand the depositional history of Quaternary deposits. A 1:100,000 scale geologic map was made by combining previous geologic maps, regional soil maps, and recent field investigations. In addition to the geologic mapping, drill hole lithologic data from water wells and oil and gas exploration were compiled and lithologic units simplified to best represent the stratigraphy of the Quaternary deposits. From these subsurface data, a 3D subsurface model was constructed, trimmed at the surface by a digital elevation model, and a bedrock surface foundation gridded from drill hole data was added. The surface of the 3D model was then compared visually to the surficial geologic map. Cross sections were constructed from the 3D model and compared to site-specific drilling that was done as part of this project. Finally, the model was examined in detail to reconstruct the depositional history of the subsurface alluvial and eolian units. Alluvial and fluvial drainage basins exposed in the subsurface have a greater areal extent than the present-day narrow drainages. Older eolian sand in the subsurface tends to be interbedded with loess indicating coeval deposition. Holocene sand, both eroded from bedrock exposed at the surface north of the study area and reworked from the South Platte River, buries most of the interbedded older sand and loess.

Colorado↗

PQLX: A seismic data quality control system description, applications, and users manual

We present a detailed description and users manual for a new tool to evaluate seismic station performance and characteristics by providing quick and easy transitions between visualizations of the frequency and time domains. The software is based on the probability density functions (PDF) of power spectral densities (PSD) (McNamara and Buland, 2004) and builds on the original development of the PDF stand-alone software system (McNamara and Boaz, 2005) and the seismological data viewer application PQL (IRIS-PASSCAL Quick Look) and PQLII (available through the IRIS PASSCAL program: http://www.passcal.nmt.edu/content/pql-ii-program-viewing-data). With PQLX (PQL eXtended), computed PSDs are stored in a MySQL database, allowing a user to access specific time periods of PSDs (PDF subsets) and time series segments through a GUI-driven interface. The power of the method and software lies in the fact that there is no need to screen the data for system transients, earthquakes, or general data artifacts, because they map into a background probability level. In fact, examination of artifacts related to station operation and episodic cultural noise allow us to estimate both the overall station quality and a baseline level of Earth noise at each site. The output of this analysis tool is useful for both operational and scientific applications. Operationally, it is useful for characterizing the current and past performance of existing broadband stations, for conducting tests on potential new seismic station locations, for evaluating station baseline noise levels (McNamara and others, 2009), for detecting problems with the recording system or sensors, and for evaluating the overall quality of data and metadata. Scientifically, the tool allows for mining of PSDs for investigations on the evolution of seismic noise (for example, Aster and others, 2008; and Aster and others, 2010) and other phenomena. Currently, PQLX is operational at several organizations including the USGS National Earthquake Information Center (NEIC), the USGS Albuquerque Seismological Laboratory (ASL), and the Incorporated Research Institutions in Seismology (IRIS) Data Management Center (DMC) for station monitoring and instrument response quality control. The PQLX system is available to the community at large through the U.S. Geological Survey (USGS) (http://ehpm-earthquake.wr.usgs.gov/research/software/pqlx.php) and IRIS (http://www.iris.edu/software/pqlx). Also provided is a fully searchable website for bug reporting and enhancement requests (http://wush.net/bugzilla/PQLX). The first part of this document aims to describe and illustrate some of the features and capabilities of the software. The second part of this document is a detailed users manual that covers installation procedures, system requirements, operations, bug reporting, and software components (Appendix).

Open-File Report↗

Generalized water-level contours, September-October 2000 and March-April 2001, and long-term water-level changes, at the U.S. Air Force Plant 42 and vicinity, Palmdale, California

Historically, the U.S. Air Force Plant 42 has relied on ground water as the primary source of water owing, in large part, to the scarcity of surface water in the region. Groundwater withdrawal for municipal, industrial, and agricultural use has affected ground-water levels at U.S. Air Force Plant 42, and vicinity. A study to document changes in groundwater gradients and to present historical water-level data was completed by the U.S. Geological Survey in cooperation with the U.S. Air Force. This report presents historical water-level data, hydrographs, and generalized seasonal water-level and water-level contours for September?October 2000 and March?April 2001. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water flow systems, and consequently water availability. During September?October 2000 and March?April 2001 the U.S. Geological Survey and other agencies made a total of 102 water-level measurements, 46 during September?October 2000 and 56 during March?April 2001. These data document recent conditions and, when compared with historical data, document changes in ground-water levels. Two water-level contour maps were drawn: the first depicts water-level conditions for September?October 2000 map and the second depicts water-level conditions for March?April 2001 map. In general, the water-level contour maps show water-level depressions formed as result of ground-water withdrawal. One hundred sixteen long-term hydrographs, using water-level data from 1915 through 2000, were constructed to show water-level trends in the area. The hydrographs indicate that water-level decline occurred throughout the study area, with the greatest declines south of U.S. Air Force Plant 42.

Scientific Investigations Report↗

Flood-inundation maps for the North Fork Kentucky River at Hazard, Kentucky

Digital flood-inundation maps for a 7.1-mile reach of the North Fork Kentucky River at Hazard, Kentucky (Ky.), were created by the U.S. Geological Survey (USGS) in cooperation with the Kentucky Silver Jackets and the U.S. Army Corps of Engineers Louisville District. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at https://water.usgs.gov/osw/flood_inundation/ , depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the North Fork Kentucky River at Hazard, Ky. (USGS station number 03277500). Near-real-time stages at this streamgage may be obtained on the internet from the USGS National Water Information System at https://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS) at https://water.weather.gov/ahps/ , which also forecasts flood hydrographs at this site (NWS AHPS site HAZK2). NWS AHPS forecast peak stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. Flood profiles were computed for the North Fork Kentucky River reach by means of a one-dimensional, step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the current stage-discharge relation (USGS rating no. 24.0) at USGS streamgage 03277500, North Fork Kentucky River at Hazard, Ky. The calibrated hydraulic model was then used to compute 26 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from approximately bankfull (14 ft) to the highest even-foot increment stage (39 ft) of the current stage-discharge rating curve. The simulated water-surface profiles were then combined with a geographic information system digital elevation model, derived from light detection and ranging data, to delineate the area flooded at each water level. The availability of these maps, along with information on the internet regarding current stage from the USGS streamgage at North Fork Kentucky River at Hazard, Ky., and forecasted stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood-response activities such as evacuations and road closures, as well as for postflood recovery efforts.

Kentucky↗

Groundwater levels in the Denver Basin bedrock aquifers of Douglas County, Colorado, 2011–19

Municipal and domestic water users in Douglas County, Colorado, rely on groundwater from the bedrock aquifers in the Denver Basin aquifer system as part of their water supply. The four principal Denver Basin bedrock aquifers are, from shallowest to deepest, the Dawson aquifer (divided administratively into “upper” and “lower” Dawson aquifers in Douglas County), the Denver aquifer, the Arapahoe aquifer, and the Laramie-Fox Hills aquifer. Increased groundwater pumping in response to rapid population growth and development has led to declining groundwater levels in Douglas County, where groundwater is a primary water source for densely populated and rural communities. The U.S. Geological Survey, in cooperation with the Rural Water Authority of Douglas County, began a study in 2011 to assess the groundwater resources of the Denver Basin bedrock aquifers within the county. The primary purpose of this report is to present a summary of groundwater levels measured during the study period (2011–19) and present results from statistical analyses of changes in groundwater-level elevations, reported above the land-surface datum, North American Vertical Datum of 1988, through time. During the study period, January 2011 through June 2019, discrete groundwater levels were routinely measured at 36 wells producing from Denver Basin bedrock aquifers within Douglas County. Of the 36 wells, 15 are instrumented with pressure transducers that record groundwater-level measurements at hourly intervals, and these data were temporally aggregated into time-series records. During 2011, wells were added to the monitoring network in phases, so that the start dates of the well records are noncontemporaneous. To keep temporal analysis among wells consistent, the periods of record used in statistical analyses were from February 2012 through February 2019 for the discrete data and from January 2012 through June 2019 for the time-series data. The upper Dawson, lower Dawson, Denver, and Arapahoe aquifers had some wells with rises in calculated groundwater-level elevations, but most wells showed declines on the basis of statistically significant trends and the relative differences in static groundwater-level elevations between the February 2012 and February 2019 measurements. Neither of the two wells in the Laramie-Fox Hills aquifer showed significant trends in groundwater-level elevations, and these wells had few static discrete measurements, precluding a comparison between 2012 and 2019 static groundwater-level elevations. Of the 13 wells in the upper Dawson, lower Dawson, Denver, and Arapahoe aquifers with significant trends in discrete groundwater-level elevation measurements, the records of 12 wells demonstrated negative trends during the study period. The upper Dawson, lower Dawson, Denver, and Arapahoe aquifers had median significant trends of −0.23, −0.31, −0.92, and −2.26 feet per year, respectively. Although the Arapahoe aquifer had the greatest negative median trend, this median only represents one well with significant trends. Otherwise, the Denver aquifer had the next greatest negative trend, with a median trend of −0.92 foot per year. Significant trends in time-series groundwater-level elevations agreed with significant trends in discrete groundwater-level elevations; for all wells with statistically significant trends in discrete and in time-series groundwater-level elevation data, trend estimates from the two records were within 0.1 foot per year of each other. Potentiometric-surface maps of the upper Dawson, lower Dawson, and Denver aquifers, created using discrete static groundwater levels measured in February 2019, show that groundwater flow direction for the upper Dawson, lower Dawson, and Denver aquifers is generally from south to north. Results of this study could guide future groundwater monitoring in the county and aid in long-term planning of water resources.

Colorado↗

ChemCam activities and discoveries during the nominal mission of the Mars Science Laboratory in Gale crater, Mars

At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day). Up to Sol 800, more than 188 000 LIBS spectra were acquired on more than 5800 points distributed over about 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during that period, together with a focus on the lessons learned from the first use of LIBS in space. For data processing, we describe new tools that had to be developed to account for the uniqueness of Mars data. With regard to chemistry, we present a summary of the composition range measured on Mars for major-element oxides (SiO 2 , TiO 2 , Al 2 O 3 , FeO T , MgO, CaO, Na 2 O, K 2 O) based on various multivariate models, with associated precisions. ChemCam also observed H, and the non-metallic elements C, O, P, and S, which are usually difficult to quantify with LIBS. F and Cl are observed through their molecular lines. We discuss the most relevant LIBS lines for detection of minor and trace elements (Li, Rb, Sr, Ba, Cr, Mn, Ni, and Zn). These results were obtained thanks to comprehensive ground reference datasets, which are set to mimic the expected mineralogy and chemistry on Mars. With regard to the first use of LIBS in space, we analyze and quantify, often for the first time, each of the advantages of using stand-off LIBS in space: no sample preparation, analysis within its petrological context, dust removal, sub-millimeter scale investigation, multi-point analysis, the ability to carry out statistical surveys and whole-rock analyses, and rapid data acquisition. We conclude with a discussion of ChemCam performance to survey the geochemistry of Mars, and its valuable support of decisions about selecting where and whether to make observations with more time and resource-intensive tools in the rover's instrument suite. In the end, we present a bird's-eye view of the many scientific results: discovery of felsic Noachian crust, first observation of hydrated soil, discovery of manganese-rich coatings and fracture fills indicating strong oxidation potential in Mars' early atmosphere, characterization of soils by grain size, and wide scale mapping of sedimentary strata, conglomerates, and diagenetic materials.

Journal of Analytical Atomic Spectrometry↗

A field guide to the central, creeping section of the San Andreas fault and the San Andreas Fault Observatory at Depth

This field trip is along the central section of the San Andreas fault and consists of eight stops that illustrate surface evidence of faulting, in general, and features associated with active fault creep, in particular. Fault creep is slippage along a fault that occurs either in association with small-magnitude earthquakes or without any associated large-magnitude earthquakes. Another aspect of the trip is to highlight where there are multiple fault traces along this section of the San Andreas fault zone in order to gain a better understanding of plate-boundary processes. The first stop is along the Calaveras fault, part of the San Andreas fault system, at a location where evidence of active fault creep is abundant and readily accessible. The stops that follow are along the San Andreas fault and at convenient locations to present and discuss rock types juxtaposed across the fault that have been transported tens to hundreds of kilometers by right-lateral motion along the San Andreas fault. Stops 6 and 7 are examples of recent studies of different aspects of the fault: drilling into the fault at the depth of repeating magnitude (M) 2 earthquakes with the San Andreas Fault Observatory at Depth (SAFOD) and the geological, geophysical, and seismological study of M 6 earthquakes near the town of Parkfield. Along with the eight official stops on this field trip are 12 “rolling stops”—sites of geologic interest that add to the understanding of features and processes in the creeping section of the fault. Many of the rolling stops are located where stopping is difficult to dangerous; some of these sites are not appropriate for large vehicles (buses) or groups; some sites are not appropriate for people at all. We include photographs of or from many of these sites to add to the reader's experience without adding too many stops or hazards to the trip. An extensive set of literature is available for those interested in the San Andreas fault or in the creeping section, in particular. For more scientifically oriented overviews of the fault, see Wallace ( 1990 ) and Irwin ( 1990 ); for a more generalized overview with abundant, colorful illustrations, see Collier ( 1999 ). Although the presence of small sections of the San Andreas fault was known before the great 1906 San Francisco earthquake, it was only after that event and subsequent geologic investigations reported in Lawson ( 1908 ) that showed the fault as a long structure, extending all the way from east of Los Angeles into northern California. Prentice ( 1999 ) described the importance of the 1908 “Lawson report” and how it pivotally influenced the understanding of the San Andreas. Hill ( 1981 ) presented a wonderful introduction to the evolution of thought on the San Andreas. Geologic maps and maps of the most recently active fault trace in the creeping section, or large parts of it, include those by Brown ( 1970 ), Dibblee ( 1971 , 1980 ), and Wagner et al. ( 2002 ); detailed geologic maps are discussed at various stops in this guide. Various aspects of the creeping section of the San Andreas fault have been the focus of many geologic field trips in the past few decades. Guidebooks for some of those trips include those by Gribi ( 1963a , 1963b ), Brabb et al. ( 1966 ), Rogers ( 1969 ), Bucknam and Haller ( 1989 ), Harden et al. ( 2001 ), and Stoffer ( 2005 ). The creeping section of the San Andreas fault zone lies between areas that experienced large-displacement surface breakage during great earthquakes in 1857 and 1906 (Fig. 1 inset). Burford and Harsh ( 1980 ) divided the creeping section into three segments: (1) a northwest section where the creep rate increases to the southeast in step-like increments, (2) a central section where the creep rate is relatively constant at a maximum value of ∼30 mm/yr (∼1.2 in/yr), and (3) a southeast section where the creep rate decreases to the southeast (Fig. 2 ). The rate of slip along the creeping section of the fault zone has been measured using creepmeters, alignment arrays, and laser distance-measuring devices. The aperture of measurements over which these measurements are made ranges from 10 m (∼33 ft) (creepmeters) to 100 m (∼330 ft) (alignment arrays) to kilometers and tens of kilometers (laser measuring devices). Creepmeter and alignment-array measurements are here termed “near-fault” measurements; laser measurements over distances of 1–2 km (∼0.6–1.2 mi) are termed “intermediate-scale” measurements; laser measurements over tens of kilometers (miles) are termed “broadscale” measurements. Comparisons among near-fault, intermediate-scale, and broadscale measurements and geologic maps show that the northwest part of the creeping section of the fault is composed of two narrow zones of active deformation, one along the San Andreas fault and one along the Calaveras-Paicines fault, whereas the central and southeast sections are both composed of a single relatively narrow zone of deformation. The southeast section is transitional to a locked zone southeast of Cholame; a locked fault is one that slips only in association with a moderate to large earthquake. Throughout the creeping section of the San Andreas fault zone, broadscale measurements generally indicate more deformation than near-fault and intermediate-scale measurements, which are in reasonably close agreement except at Monarch Peak (Mustang Ridge), near the center of the creeping section and our Stop 5 ((Figs. 1 ) and 2 ). Features that we see on this trip include offset street curbs, closed depressions (sag ponds), fault scarps (steep slopes formed by movement along a fault), a split and displaced tree, offset fence lines, fresh fractures, and offset road lines (Fig. 3 is a sketch showing some of the landforms that represent deformation by an active fault). We also see evidence of long-term maturity of the San Andreas fault, as indicated by fault features and displaced rock types (Fig. 4 ). Finally, we will visit sites of ongoing research into the processes associated with earthquakes and their effects. Discussions include drilling into the San Andreas fault at the SAFOD drill site and the 2004 Parkfield earthquake and its effects and implications.

California↗

Water-resources activities of the U.S. Geological Survey in Kansas; fiscal years 1985 and 1986

The principal mission of the U.S. Geological Survey, Water Resources Division, in Kansas is to investigate the occurrence, quantity, quality, distribution, and movement of surface and groundwater throughout the State. Primary activities include the systematic collection, analysis and interpretation of hydrologic data, evaluation of water demands, and water resources research. Hydrologic investigations are conducted through: (1) data collection programs, (2) statewide or regional investigations, (3) local or areal investigations, and (4) research. These projects are funded through cooperative agreements with state and local agencies, transfer of funds from other federal agencies, and direct federal funds. Forty-three water related projects were ongoing during fiscal years 1985 and 1986 in Kansas. This report describes for each project the problem that initiated the study, the objectives of the project, the approach designed to achieve the objectives, and significant milestones or publications that resulted during fiscal years 1985 and 1986. Information on more than 2,150 data collection stations in Kansas is presented in maps and tables. A list of 47 project reports published or released by the U.S. Geological Survey, its cooperators, or technical and scientific organizations during 1985 and 1986 is provided. (Author 's abstract)

Open-File Report↗

Water-resources activities of the U.S. Geological Survey in Kansas; fiscal years 1987 and 1988

The principal mission of the U.S. Geological Survey, Water Resources Division, in Kansas is to investigate the occurrence, quantity, quality, distribution, and movement of surface and groundwater throughout the State. Primary activities include the systematic collection, analysis, and interpretation of hydrologic data, evaluation of water demands, and water resources research. Hydrologic investigations are conducted through four types of studies: (1) data collection programs; (2) statewide or regional investigations; (3) local or area investigations; and (4) research. These studies are funded through cooperative agreements with State and local agencies, transfer of funds from other agencies, and direct Federal funds. Thirty-six water related studies were ongoing during fiscal years 1987 and 1988 in Kansas. This report describes for each study the problem that initiated the study, the objectives of the study, the approach designed to achieve the objectives, and significant milestones and publications that resulted during fiscal years 1987 and 1988. Information on more than 2,100 data collection stations in Kansas is presented in maps and tables. A list of 46 reports and abstracts published or released by the U.S. Geological Survey, its cooperators, or technical and scientific organizations during 1987 and 1988 is provided. (USGS)

Open-File Report↗

Flood plain delineation for the Fremont River and Bull Creek, Hanksville, Utah

Predicted inundation maps for the Fremont River and Bull Creek in Hanksville, Utah, were developed using one-dimensional hydraulic models. Estimates of the 1-percent chance (100-year) peak streamflows were determined for the Fremont River and Bull Creek study reaches by using annual peak series data from streamflow-gaging stations and regional peak-flow regression equations. Surveyed topographic data for the study reaches were processed for use in the one-dimensional hydraulic models. The 1-percent chance (100-year) peak streamflows were simulated with hydraulic models to obtain predicted water-surface elevations. Water-surface elevations were then used to map the predicted inundation on a recent aerial photograph. The 1-percent chance (100-year) flood plain for the Fremont River in Hanksville, Utah, included some agricultural lands and did not encroach upon the town. The 1-percent chance (100-year) flood plain on the west side of Bull Creek was found to include a large portion of the town of Hanksville, Utah.

Utah↗

Characterization of the hydrologic resources of San Miguel County, New Mexico, and identification of hydrologic data gaps, 2011

The U.S. Geological Survey (USGS), in cooperation with San Miguel County, New Mexico, conducted a study to assess publicly available information regarding the hydrologic resources of San Miguel County and to identify data gaps in that information and hydrologic information that could aid in the management of available water resources. The USGS operates four continuous annual streamgages in San Miguel County. Monthly discharge at these streamgages is generally bimodally distributed, with most runoff corresponding to spring runoff and to summer monsoonal rains. Data compiled since 1951 on the geology and groundwater resources of San Miguel County are generally consistent with the original characterization of depth and availability of groundwater resources and of source aquifers. Subsequent exploratory drilling identified deep available groundwater in some locations. Most current (2011) development of groundwater resources is in western San Miguel County, particularly in the vicinity of El Creston hogback, the hogback ridge just west of Las Vegas, where USGS groundwater-monitoring wells indicate that groundwater levels are declining. Regarding future studies to address identified data gaps, the ability to evaluate and quantify surface-water resources, both as runoff and as potential groundwater recharge, could be enhanced by expanding the network of streamgages and groundwater-monitoring wells throughout the county. A series of seepage surveys along the lengths of the rivers could help to determine locations of surface-water losses to and gains from the local groundwater system and could help to quantify the component of streamflow attributable to irrigation return flow; associated synoptic water-quality sampling could help to identify potential effects to water quality attributable to irrigation return flow. Effects of groundwater withdrawals on streamflow could be assessed by constructing monitoring wells along transects between production wells and stream reaches of interest to monitor decline or recovery of the water table, to quantify the timing and extent of water-table response, and to identify the spatial extent of capture zones. Assessment of groundwater potential could be aided by a county-wide distribution of water-level information and by a series of maps of groundwater potential, compiled for each individual aquifer, including saline aquifers, for which the potential for municipal use through desalination could be explored. A county-wide geographic information system hydrologic geodatabase could provide a comprehensive picture of water use in San Miguel County and could be used by San Miguel County as a decision-support tool for future management decisions.

New Mexico↗

Well log analysis to assist the interpretation of 3-D seismic data at Milne Point, north slope of Alaska

In order to assess the resource potential of gas hydrate deposits in the North Slope of Alaska, 3-D seismic and well data at Milne Point were obtained from BP Exploration (Alaska), Inc. The well-log analysis has three primary purposes: (1) Estimate gas hydrate or gas saturations from the well logs; (2) predict P-wave velocity where there is no measured P-wave velocity in order to generate synthetic seismograms; and (3) edit P-wave velocities where degraded borehole conditions, such as washouts, affected the P-wave measurement significantly. Edited/predicted P-wave velocities were needed to map the gas-hydrate-bearing horizons in the complexly faulted upper part of 3-D seismic volume. The estimated gas-hydrate/gas saturations from the well logs were used to relate to seismic attributes in order to map regional distribution of gas hydrate inside the 3-D seismic grid. The P-wave velocities were predicted using the modified Biot-Gassmann theory, herein referred to as BGTL, with gas-hydrate saturations estimated from the resistivity logs, porosity, and clay volume content. The effect of gas on velocities was modeled using the classical Biot-Gassman theory (BGT) with parameters estimated from BGTL.

Scientific Investigations Report↗