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2015

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Articles 301 - 330 of 1152

Full-Text Articles in Earth Sciences

An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey Aug 2015

An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three studies investigating clay mineralogy on, or near the martian surface, with an introductory chapter, introducing and linking the three studies. Chapter two is on the subject of clay mineral synthesis, including Fe/Mg clay minerals which have been detected at multiple locations across the southern highlands. These Fe/Mg clay minerals have been previously interpreted as forming in anoxic/reducing environments, conducive to the preservation of organic matter. The results of this study suggest that the previous interpretation of Fe/Mg-rich clay as requiring anoxic/reducing conditions may not be accurate, as the minor presence of Mg (below what …


Using Pre-Tests And Post-Tests To Measure Student Learning, Rebecca Teed Aug 2015

Using Pre-Tests And Post-Tests To Measure Student Learning, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

How much are students actually learning in our classes? The best predictor of a student’s final exam grade is how much content knowledge they had coming in. This prior knowledge can be assessed with a pre-test, allowing instructors to adjust the course based on what students already know or don’t know. The instructor can use the pre-test scores to create student groups that are either heterogeneous (for cooperative learning) or homogeneous (for differentiated instruction) with respect to content background at the start of term. A curriculum designer wishing to compare learning gains for different teaching tools such as cooperative learning …


U.S. Drought Monitor, August 25, 2015, Anthony Artusa Aug 2015

U.S. Drought Monitor, August 25, 2015, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 25, 2015 (8/25/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Rapid Label-Free Detection Of E. Coli Using Antimicrobial Peptide Assisted Impedance Spectroscopy, Keren Jieng, Hashem Etayash, Sarfuddin Azmi, Selvaraj Naicker, Mahtab Hassanpourfard, Parmiss Mojir Shaibani, Garima Thakur, Kamaljit Kaur, Thomas Thundat Aug 2015

Rapid Label-Free Detection Of E. Coli Using Antimicrobial Peptide Assisted Impedance Spectroscopy, Keren Jieng, Hashem Etayash, Sarfuddin Azmi, Selvaraj Naicker, Mahtab Hassanpourfard, Parmiss Mojir Shaibani, Garima Thakur, Kamaljit Kaur, Thomas Thundat

Pharmacy Faculty Articles and Research

There is an increasing demand for rapid detection of waterborne pathogens to monitor drinking water safety. We demonstrate a compact, label-free sensor array for rapid detection of Escherichia coli (E. coli) in contaminated water samples using antimicrobial peptide assisted impedimetric sensor platform. Interdigitated electrode arrays immobilized with the antimicrobial peptide Colicin V (ColV) were used to screen the affinity towards different bacterial strains by monitoring impedance variations in real-time. This ColV assisted impedance biosensor exhibited high selectivity towards Gram-negative strains particularly towards E. coli strains. This selective detection of E. coli from other strains was observed at 10 …


Flood-Inundation Maps For The St. Marys River At Decatur, Indiana, Kellan R. Strauch Aug 2015

Flood-Inundation Maps For The St. Marys River At Decatur, Indiana, Kellan R. Strauch

United States Geological Survey: Water Reports and Publications

Digital flood-inundation maps for an 8.9-mile reach of the St. Marys River at Decatur, Indiana, were developed by the U.S. Geological Survey (USGS), in cooperation with the Indiana Office of Community and Rural Affairs. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site (http://water.usgs.gov/osw/flood_inundation/), depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) of the St. Marys River at Decatur (USGS station number 04181500). The maps are useful for estimating near-real-time areas of inundation by referencing concurrent USGS streamgage information at http://waterdata.usgs.gov/. In addition, the streamgage …


The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox Aug 2015

The Science And Practice Of River Restoration, Ellen E. Wohl, Stuart N. Lane, Andrew C. Wilcox

Geosciences Faculty Publications

River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration …


Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna Aug 2015

Shaw T. & Alenka ČUk, 2015. Slovene Karst And Caves In The Past, Arrigo A. Cigna

International Journal of Speleology

No abstract provided.


U.S. Drought Monitor, August 18, 2015, Chris Fenimore Aug 2015

U.S. Drought Monitor, August 18, 2015, Chris Fenimore

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 18, 2015 (8/18/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins Aug 2015

Black Carbon Concentrations In Snow At Tronsen Meadow In Central Washington From 2012 To 2013: Temporal And Spatial Variations And The Role Of Local Forest Fire Activity, Ian Delaney, Susan D. Kaspari, Matthew Jenkins

Geological Sciences Faculty Scholarship

Characterizing black carbon (BC) concentrations in the seasonal snowpack is of interest because BC deposition on snow can reduce albedo and accelerate melt. In Washington State, USA snowmelt from the seasonal snowpack provides an important source of water resources, but minimal work has been done characterizing BC concentrations in snow in this region. BC concentrations in snow were monitored over two winters (2012 and 2013) at Tronsen Meadow, located near Blewett Pass in the eastern Cascade Mountains in Central Washington, to characterize spatial and temporal variations in BC concentrations, and the processes affecting BC concentrations in the snowpack. BC concentrations …


Dendrochronological Analysis Of The Mann Homestead Aug 2015

Dendrochronological Analysis Of The Mann Homestead

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


Lahar Infrasound Associated With Volcán Villarrica's 3 March 2015 Eruption, Jeffrey B. Johnson, Jose L. Palma Aug 2015

Lahar Infrasound Associated With Volcán Villarrica's 3 March 2015 Eruption, Jeffrey B. Johnson, Jose L. Palma

Geosciences Faculty Publications and Presentations

The paroxysmal 2015 eruption of Volcán Villarrica (Chile) produced a 2.5 h long lahar, which descended more than 20 km within the Rio Correntoso/Turbio drainage and destroyed two small bridges. A three-element infrasound array 10 km from the summit, and 4 km from the lahar’s closest approach, was used to study the flow’s progression. Array processing using cross-correlation lag times and semblance places constraints on the lahar’s dynamics, including detection of an initial flow pulse that traveled from 2 to 12 km at an average speed of 38m/s. Subsequently, the lahar signal evolved to a relatively stationary infrasonic tremor located …


Evaluation Of Regional Climate Models With Remotely Sensed Evapotranspiration Data, Doruk Ozturk Aug 2015

Evaluation Of Regional Climate Models With Remotely Sensed Evapotranspiration Data, Doruk Ozturk

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Water is one of the most precious resources on Earth. Managing water resources is a complex discipline that requires accurate data, which in turn means that the management of water resources is limited by the availability and quality of these datasets. Evapotranspiration (ET) is one of these key datasets, but is also one that is lacking in large-scale spatial distribution with traditional methods such as weighing lysimeters or Bowen ratio. This is a quantity that needs to be evaluated in regional and global climate models since it is a substantial component of the land surface-atmosphere interaction. In order to overcome …


Modling Of Upper Ocean Heat Budget Variations In Response To The Passage Of Super Typhoon Sinlaku (2008) In The Western North Pacific, Zhe-Wen Zheng, Nan-Jung Kuo, Quanan Zheng, Ganesh Gopalakrishnan Aug 2015

Modling Of Upper Ocean Heat Budget Variations In Response To The Passage Of Super Typhoon Sinlaku (2008) In The Western North Pacific, Zhe-Wen Zheng, Nan-Jung Kuo, Quanan Zheng, Ganesh Gopalakrishnan

Journal of Marine Science and Technology–Taiwan

In 2008, Super Typhoon Sinlaku (2008) passed over a preexisting cyclonic eddy (PCE) in the western North Pacific, causing an extreme cooling response at 22.5°N, 125°E. This case provides a rare opportunity to explore the physical mechanisms that trigger an extreme cooling response to a typhoon underlying the influence of PCEs. In this study, cooling response to Sinlaku was observed by TMI/AMSR-E microwave SSTs and simulated using the Regional Ocean Modeling System. To elucidate the impact of a PCE, in addition to standard run (EXPstd), another experiment that eliminates the influence of a PCE (EXPnonPCE) was designed and executed. By …


Large-Scale And High-Resolution 3-D Cave Mapping By Terrestrial Laser Scanning: A Case Study Of The Domica Cave, Slovakia, Michal Gallay, Ján Kaňuk, Zdenko Hochmuth, John D. Meneely, Jaroslav Hofierka, Vladimír Sedlák Aug 2015

Large-Scale And High-Resolution 3-D Cave Mapping By Terrestrial Laser Scanning: A Case Study Of The Domica Cave, Slovakia, Michal Gallay, Ján Kaňuk, Zdenko Hochmuth, John D. Meneely, Jaroslav Hofierka, Vladimír Sedlák

International Journal of Speleology

Mapping and modelling the complicated geometry of caves is a challenging task that has traditionally been undertaken by tacheometric surveying methods. These methods are excellent for capturing the general shape of a cave system but they are not suitable for high-speed, high-resolution mapping of complex surfaces found in this environment. Terrestrial laser scanning (TLS) technologies can acquire millions of points represented by 3-D coordinates, at very high spatial densities on complex multifaceted surfaces within minutes. In the last few years, advances in measurement speed, reduction in size / cost and increased portability of this technology has revolutionised the collection of …


Simulation Of Groundwater Flow And Analysis Of The Effects Of Water-Management Options In The North Platte Natural Resources District, Nebraska, Steven M. Peterson, Amanda T. Flynn, Joseph Vrabel, Derek W. Ryter Aug 2015

Simulation Of Groundwater Flow And Analysis Of The Effects Of Water-Management Options In The North Platte Natural Resources District, Nebraska, Steven M. Peterson, Amanda T. Flynn, Joseph Vrabel, Derek W. Ryter

United States Geological Survey: Water Reports and Publications

The North Platte Natural Resources District (NPNRD) has been actively collecting data and studying groundwater resources because of concerns about the future availability of the highly inter-connected surface-water and groundwater resources. This report, prepared by the U.S. Geological Survey in cooperation with the North Platte Natural Resources District, describes a groundwater-flow model of the North Platte River valley from Bridgeport, Nebraska, extending west to 6 miles into Wyoming. The model was built to improve the understanding of the interaction of surface-water and groundwater resources, and as an optimization tool, the model is able to analyze the effects of water-management options …


Dendrochronological Analysis Of The Crowe Barn Aug 2015

Dendrochronological Analysis Of The Crowe Barn

Historic Structures

Dating historical structures using dendrochronology. The Historical Structures collection consists of reports that are the result of dendochronological analysis of timbers from structures in Pennsylvania and Ohio. Contributors: Wiesenberg, Nicholas


U.S. Drought Monitor, August 11, 2015, Brian Fuchs Aug 2015

U.S. Drought Monitor, August 11, 2015, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 11, 2015 (8/11/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Is Atmospheric Phosphorus Pollution Altering Global Alpine Lake Stoichiometry?, Janice Brahney, Natalie Mahowald, Daniel S. Ward, Ashley P. Ballantyne, Jason C. Neff Aug 2015

Is Atmospheric Phosphorus Pollution Altering Global Alpine Lake Stoichiometry?, Janice Brahney, Natalie Mahowald, Daniel S. Ward, Ashley P. Ballantyne, Jason C. Neff

Watershed Sciences Faculty Publications

Anthropogenic activities have significantly altered atmospheric chemistry and changed the global mobility of key macronutrients. Here we show that contemporary global patterns in nitrogen (N) and phosphorus (P) emissions drive large hemispheric variation in precipitation chemistry. These global patterns of nutrient emission and deposition (N:P) are in turn closely reflected in the water chemistry of naturally oligotrophic lakes (r2 = 0.81, p < 0.0001). Observed increases in anthropogenic N deposition play a role in nutrient concentrations (r2 = 0.20, p < 0.05); however, atmospheric deposition of P appears to be major contributor to this pattern (r2 = 0.65, p < 0.0001). Atmospheric simulations indicate a global increase in P deposition by 1.4 times the preindustrial rate largely due to increased dust and biomass burning emissions. Although changes in the mass flux of global P deposition are smaller than for N, the impacts on primary productivity may be greater because, on average, one unit of increased P deposition has 16 times the influence of one unit of N deposition. These stoichiometric considerations, combined with the evidence presented here, suggest that increases in P deposition may be a major driver of alpine Lake trophic status, particularly in the Southern Hemisphere. These results underscore the need for the broader scientific community to consider the impact of atmospheric phosphorus deposition on the water quality of naturally oligotrophic lakes.


Quantifying Groundwater/Surface-Water Interactions In Tributaries To The Wabash River Using Radon‐222 And Other Environmental Isotopes, Philine Bogeholz, Marty Frisbee Aug 2015

Quantifying Groundwater/Surface-Water Interactions In Tributaries To The Wabash River Using Radon‐222 And Other Environmental Isotopes, Philine Bogeholz, Marty Frisbee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Groundwater/surface-water interactions have not been extensively studied in tile-drained watersheds where natural recharge processes are “short circuited” by routing water out of the soil-zone and into nearby drainage ditches. This practice likely impacts baseflow generation in the Wabash River of Indiana. If true, then how is baseflow affected in small tributaries to the Wabash? To answer this question, we investigated groundwater/surface-water interactions in four small tributary drainages to the Wabash River and Sugar Creek. These drainages share common geologic characteristics and are deeply incised providing a window into groundwater flow processes. We sampled these drainages for general geochemistry, radon-222 ( …


Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro Aug 2015

Comparative Sorption Of Methylene Blue Onto Hydrophobic Clays, Alvaro D. Sponza, Natalia J. Fernandez, David Yang, Karla A. Ortiz, Abel E. Navarro

Publications and Research

Chemical modifications of clay to remove methylene blue (MB) from aqueous solutions at room temperature were compared. Natural bentonite (NC) was modified by cation exchange with hexadecyltrimethylammonium chloride (HC), bencyltriethylammonium chloride (BC), and tetramethylammonium chloride (TC) to reverse the surface polarity of the hydrophilic bentonite. The adsorption of MB was studied and fitted by the adsorption theories of Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin. Equilibrium parameters were calculated, indicating that chemical modification did not improve the adsorption, due to the electrostatic adsorption mechanism. Specific surface area was determined, reporting the following trend: NC > TC > BC > HC. Isotherms show that TC is …


Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager Aug 2015

Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager

Dissertations and Theses

A glacier responds to changes in climate by subsequent retreat and advance as a result of changes in snow inputs and outputs. Understanding these changes is important because shrinking glaciers limit and diminish local water resources. They contribute to alpine runoff in the late-summer months by delaying the maximum runoff until late in the melt season. A comprehensive glacier and perennial snowfield inventory has not been completed for the Three Sisters in Central Oregon. Using aerial photography, Digital Elevation Models (DEMs), previous studies, and historical ground based photographs these glacier and perennial snowfields were defined and their surface area change …


U.S. Drought Monitor, August 4, 2015, Mark D. Svoboda Aug 2015

U.S. Drought Monitor, August 4, 2015, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 4, 2015 (8/4/15) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Predicting Landscape-Scale Co 2 Flux At A Pasture And Rice Paddy With Long-Term Hyperspectral Canopy Reflectance Measurements, J. H. Matthes, S. H. Knox, C. Sturtevant, O. Sonnentag Aug 2015

Predicting Landscape-Scale Co 2 Flux At A Pasture And Rice Paddy With Long-Term Hyperspectral Canopy Reflectance Measurements, J. H. Matthes, S. H. Knox, C. Sturtevant, O. Sonnentag

Dartmouth Scholarship

Measurements of hyperspectral canopy reflectance provide a detailed snapshot of information regarding canopy biochemistry, structure and physiology. In this study, we collected 5 years of repeated canopy hyperspectral reflectance measurements for a total of over 100 site visits within the flux footprints of two eddy covariance towers at a pasture and rice paddy in northern California. The vegetation at both sites exhibited dynamic phenology, with significant interannual variability in the timing of seasonal patterns that propagated into interannual variability in measured hyperspectral reflectance. We used partial least-squares regression (PLSR) modeling to leverage the information contained within the entire canopy reflectance …


Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman Aug 2015

Using Data Visualization Software To Aid In The Analysis Of Geographical Data, Matthew R. Evers, Inzamam Rahaman

STAR Program Research Presentations

NASA Web World Wind (Web WW) is designed to visualize and manage geographical data. As a first implementation of visualization and analysis, we designed an application to map earthquake data onto the globe. Portions of this code were merged with application monitoring magnetic field anomalies possibly associated with earthquake precursor activity. Web WW enabled the visualization of the directional vectors from this data to point to the source location of the earthquake. We also developed a prototype urban management application which utilizes OpenStreetMaps to provide simple features such as route navigation, geographical and services information in an area of interest. …


Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman Aug 2015

Identifying Glacial Movement Through Fluvial Sediment Analysis, Alexis D. Freeman

STAR Program Research Presentations

The primary purpose of this study is to better understand how climate affects river dynamics. It is also important to understand the relationship between glaciers and the transportation of sediments, as this allows us to study changes in transport through time. The studied sediments were gathered from outcrops located in Fresno Ca, off of Friant road. The origin of these sediments are the Sierra Nevada Mountains. Mesozoic metasedimentary and metavolcanic sediments are derived from the foothills, while the granitic sediments are derived from higher up in the mountains. The sediments are characterized by both their degree of rounding, and their …


Using Bromide Tracer To Measure Uranium Diffusivity In Ground Water Sediments, Francis Michael Tee, Morris E. Jones, Megan K. Dustin, Sharon Bone, John Bargar Aug 2015

Using Bromide Tracer To Measure Uranium Diffusivity In Ground Water Sediments, Francis Michael Tee, Morris E. Jones, Megan K. Dustin, Sharon Bone, John Bargar

STAR Program Research Presentations

More than 129 million liters of groundwater are contaminated with uranium at Old Rifle, Colorado – a former uranium-processing site that operated until 1958. The original Department of Energy (DOE) strategy for remediation, involving natural flushing of U from the groundwater through mixing with surface water, has not proven successful. Thin pockets of silt-, clay-, and organic-rich sediments referred to as naturally reduced zones (NRZs) act both as sinks and sources of U to the aquifer, contribute to plume persistence, and appear to be diffusion limited controlled.

To better understand how the NRZs are diffusion limited controlled, a bromide tracer …


Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator Aug 2015

Ua24 Mcicsl Newsletter - August 2015, Shannon R. Trimboli Education Coordinator

MCICSL Newsletter

This issue includes the following:

Bat Night was a success for education and research

MCICSL participated in national network strategic planning

as well as Summer research opportunities


Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her Aug 2015

Geo-Needs Focus Group Meetings Report Executive Summary, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs Stakeholder Needs Assessment for Broadening Participation in the Geoscience Workforce. Executive summary. The full meeting report is available at http://scholarworks.wmich.edu/geology_reports/1/


Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her Aug 2015

Geo-Needs: Stakeholder Needs Assessment For Broadening Participation In The Geoscience Workforce, Heather L. Petcovic, Sheldon P. Turner, Emily Geraghty Ward, Tina Cartwright, Nicole Ladue, David Mogk, Andrew P.K. Bentley, Xai Her

Geological and Environmental Sciences Reports

Geo-Needs focus group meetings report from the August 5-7 and 9-11, 2015 conference at the Nothern Illinois University Conference Center in Naperville, Illinois.

Despite a significant investment of resources, underrepresented minorities constitute ~8% of the geoscience-related workforce, making the geosciences one of the least diverse of all science, technology, engineering, and math (STEM) disciplines. While this pattern of underrepresentation has been attributed to numerous factors, the Geo-Needs project is focused on lack of access to undergraduate courses and programs of study at two-year technical and community colleges (2YCs) and minority-serving institutions (MSIs). Based on our analysis, only about 2.5% of …


The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn Aug 2015

The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation encompasses two studies: one developing virtual field trips for mobile devices for an innovative approach to lower-division geoscience education, and the other examining the role of rock strength in river erosion and landscape evolution.

The education study involves the development of three virtual field trip modules (Geologic Time, Geologic Structures, and Hydrologic Processes, all free on iTunes and Google Play) that lead students down a virtual Colorado River through Grand Canyon by physically moving around their campus quad, football field or other location, using their GPS-equipped smart phone or tablet. As students reach each location in the scaled …