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Full-Text Articles in Physical Sciences and Mathematics

3-D Transient Hydraulic Tomography In Unconfined Aquifers With Fast Drainage Response, Michael Cardiff, Warren Barrash Dec 2011

3-D Transient Hydraulic Tomography In Unconfined Aquifers With Fast Drainage Response, Michael Cardiff, Warren Barrash

CGISS Publications and Presentations

We investigate, through numerical experiments, the viability of three-dimensional transient hydraulic tomography (3DTHT) for identifying the spatial distribution of groundwater flow parameters (primarily, hydraulic conductivity K) in permeable, unconfined aquifers. To invert the large amount of transient data collected from 3DTHT surveys, we utilize an iterative geostatistical inversion strategy in which outer iterations progressively increase the number of data points fitted and inner iterations solve the quasi-linear geostatistical formulas of Kitanidis. In order to base our numerical experiments around realistic scenarios, we utilize pumping rates, geometries, and test lengths similar to those attainable during 3DTHT field campaigns performed at …


Hydrological Parameter Estimations From A Conservative Tracer Test With Variable-Density Effects At The Boise Hydrogeophysical Research Site, B. Dafflon, Warren Barrash, Michael Cardiff, T. C. Johnson Dec 2011

Hydrological Parameter Estimations From A Conservative Tracer Test With Variable-Density Effects At The Boise Hydrogeophysical Research Site, B. Dafflon, Warren Barrash, Michael Cardiff, T. C. Johnson

CGISS Publications and Presentations

Reliable predictions of groundwater flow and solute transport require an estimation of the detailed distribution of the parameters (e.g., hydraulic conductivity, effective porosity) controlling these processes. However, such parameters are difficult to estimate because of the inaccessibility and complexity of the subsurface. In this regard, developments in parameter estimation techniques and investigations of field experiments are still challenging and necessary to improve our understanding and the prediction of hydrological processes. Here we analyze a conservative tracer test conducted at the Boise Hydrogeophysical Research Site in 2001 in a heterogeneous unconfined fluvial aquifer. Some relevant characteristics of this test include: variable-density …


Co2 Sequestration In Basalt: Carbonate Mineralization And Fluid Substitution, Thomas L. Otheim, Ludmila Adam, Kasper Van Wijk, Michael L. Batzle, Travis Mcling, Robert Podgorney Dec 2011

Co2 Sequestration In Basalt: Carbonate Mineralization And Fluid Substitution, Thomas L. Otheim, Ludmila Adam, Kasper Van Wijk, Michael L. Batzle, Travis Mcling, Robert Podgorney

CGISS Publications and Presentations

Geologicalsequestration of carbon dioxide in deep reservoirs may provide alarge-scale option for reducing the emissions of this gas intothe atmosphere. The effectiveness of sequestration depends on the storagecapacity and stability of the reservoir and risk of leakageinto the overburden. Reservoir rocks can react with a CO2-watermixture, potentially resulting in the precipitation of minerals in theavailable matrix pore space and within pre-existing fractures. This inducedmineralization may form internal seals that could help mitigate theleakage of CO2 into the overburden. For basaltic host rocks,carbonic acid partially dissolves minerals in the host rock, suchas the calcium plagioclase mineral, freeing various …


Temporal And Spatial Analysis Of Stream And Groundwater Interactions, Ryan Eugene Warden Dec 2011

Temporal And Spatial Analysis Of Stream And Groundwater Interactions, Ryan Eugene Warden

Boise State University Theses and Dissertations

Water chemistry and ecology of streams are impacted by the amount of water that exchanges between the surface water system and the adjacent saturated area, called the hyporheic zone, a dynamic area of stream channel sediments, which undergoes down-welling or up-welling of stream water. The rate and volume of water exchange between the surface water and the hyporheic zone are primary controls on stream ecology, but are challenging to assess. A common approach is to model the exchange rate with a one-dimensional advection-dispersion equation that includes solute exchange with transient storage zones, which is referred to as a transient storage …


A Simplified Approach For Estimating Soil Carbon And Nitrogen Stocks In Semi-Arid Complex Terrain, Melvin L. Kunkel, Alejandro N. Flores, Toni J. Smith, James P. Mcnamara, Shawn G. Benner Oct 2011

A Simplified Approach For Estimating Soil Carbon And Nitrogen Stocks In Semi-Arid Complex Terrain, Melvin L. Kunkel, Alejandro N. Flores, Toni J. Smith, James P. Mcnamara, Shawn G. Benner

Geosciences Faculty Publications and Presentations

We investigated soil carbon (C) and nitrogen (N) distribution and developed a model, using readily available geospatial data, to predict that distribution across a mountainous, semi-arid, watershed in southwestern Idaho (USA). Soil core samples were collected and analyzed from 133 locations at 6 depths (n=798), revealing that aspect dramatically influences the distribution of C and N, with north-facing slopes exhibiting up to 5 times more C and N than adjacent southfacing aspects. These differences are superimposed upon an elevation (precipitation) gradient, with soil C and N contents increasing by nearly a factor of 10 from the bottom (1100 m elevation) …


Mobile Technology As A Tool For Enhancing Student Learning In Geosciences, Sam Matson Sep 2011

Mobile Technology As A Tool For Enhancing Student Learning In Geosciences, Sam Matson

Mobile Learning Symposium

Incorporation of mobile technology into the post-secondary classroom is becoming increasingly common as universities seek to facilitate active, student-centered learning through rapid access to information, connect students with course content through social media, and evaluate digital alternatives to conventional instructor-student interaction. The m-Learning Scholars Program at Boise State University was initiated during the 2010 – 2011 academic year, and provides a venue for exploring the potential of mobile technology to enhance student learning in the geosciences. Through this program, 38 students in an introductory Earth History course for non-geoscience majors each purchased a subsidized handheld device (iPod touch) that they …


Theory And Laboratory Experiments Of Elastic Wave Scattering By Dry Planar Fractures, Thomas E. Blum, Roel Snieder, Kasper Van Wijk, Mark E. Willis Aug 2011

Theory And Laboratory Experiments Of Elastic Wave Scattering By Dry Planar Fractures, Thomas E. Blum, Roel Snieder, Kasper Van Wijk, Mark E. Willis

CGISS Publications and Presentations

Remote sensing of fractures with elastic waves is important in fields ranging from seismology to nondestructive testing. In many geophysical applications, fractures control the flow of fluids such as water, hydrocarbons or magma. While previous analytic descriptions of scattering mostly deal with very large or very small fractures (compared to the dominant wavelength), we present an analytic solution for the scattering of elastic waves from a fracture of arbitrary size. Based on the linear slip model for a dry fracture, we derive the scattering amplitude in the frequency domain under the Born approximation for all combinations of incident and scattered …


Estimating The Rayleigh-Wave Impulse Response Between Seismic Stations With The Cross Terms Of The Green Tensor, Kasper Van Wijk, T. Dylan Mikesell, Vera Schulte-Pelkum, Josh Stachnik Aug 2011

Estimating The Rayleigh-Wave Impulse Response Between Seismic Stations With The Cross Terms Of The Green Tensor, Kasper Van Wijk, T. Dylan Mikesell, Vera Schulte-Pelkum, Josh Stachnik

CGISS Publications and Presentations

The development of ambient noise tomography has provided a powerful tool to investigate the Earth's subsurface with increased resolution. Most commonly, surface-wave tomography is performed on inter-station estimates of the vertical component of Rayleigh waves, stemming from crosscorrelations of ocean-generated noise. Here, we estimate the cross terms of the Rayleigh-wave Green tensor, and show this is less sensitive to signal not in-line with the seismic stations. We illustrate this result with the Batholiths temporary seismic deployment, showing estimates of the Rayleigh wave with a higher signal-to-noise ratio and a consequently better phase-velocity dispersion curve. This approach provides an opportunity for …


Geochronologic And Isotopic Investigation Of The Koipato Formation, Northwestern Great Basin, Nevada: Implications For Late Permian-Early Triassic Tectonics Along The Western U.S. Cordillera, Nicholas Quentin Vetz Aug 2011

Geochronologic And Isotopic Investigation Of The Koipato Formation, Northwestern Great Basin, Nevada: Implications For Late Permian-Early Triassic Tectonics Along The Western U.S. Cordillera, Nicholas Quentin Vetz

Boise State University Theses and Dissertations

The volcanics of the Early Triassic Koipato Formation of central Nevada unconformably overlie the Golconda Allochthon and, classically, this relationship has been used to define the timing of the Sonoma Orogeny as post-Middle Permian to earliest Triassic. However, the Koipato Formation represents a rather isolated magmatic succession, with other western U.S. Early Mesozoic igneous provinces determined to be younger or lacking rocks of Koipato age. This isolation, coupled with the fact that the Koipato Formation does not overlap the Golconda Allochthon, has left open two possible scenarios for its tectonic history: 1) the Koipato Formation represents the earliest, post-Sonoma Orogeny …


Establishing Confidence In Surface Wave Determined Soil Profiles, Paul Michaels Jun 2011

Establishing Confidence In Surface Wave Determined Soil Profiles, Paul Michaels

CGISS Publications and Presentations

Surface waves can be used to determine the shear velocity profile from the ground surface to some depth limited by the spectral band of the seismic source. A number of factors influence the uncertainties of the determined profile. The field acquisition factors include the deployment geometry of geophones, the spectral characteristics of the geophones, recording instruments, and seismic source. A key data processing factor is the determination of a dispersion curve from the field recordings. Finally, there are important choices in conducting the inversion of the dispersion curve which leads to the final soil profile. Even if the field factors …


Interpretation Of Rayleigh-Wave Ellipticity Observed With Multicomponent Passive Seismic Interferometry At Hekla Volcano, Iceland, Matthew M. Haney, Andrew Nies, Tim Masterlark, Sarah Needy, Rikke Pedersen May 2011

Interpretation Of Rayleigh-Wave Ellipticity Observed With Multicomponent Passive Seismic Interferometry At Hekla Volcano, Iceland, Matthew M. Haney, Andrew Nies, Tim Masterlark, Sarah Needy, Rikke Pedersen

CGISS Publications and Presentations

The 2010 eruption of Eyjafjallajökull has drawn increased attention to Iceland’s Eastern Volcanic Zone (EVZ) due to the threat it poses to the heavily used air-traffic corridors of the northern Atlantic Ocean. Within the EVZ, Hekla is historically one of the most active volcanoes and has exhibited a decadal eruption pattern for the past 40 years. Hekla most recently erupted in 2000 and is thus ripe for another decadal eruption. Because Hekla is generally aseismic, except for a brief time period (hours) leading up to an eruption, monitoring has previously depended on precursory deformation signals (Linde et al., 1993). As …


Evapotranspiration In The Riparian Zone Of The Lower Boise River With Implications For Groundwater Flow, Brady Allen Johnson May 2011

Evapotranspiration In The Riparian Zone Of The Lower Boise River With Implications For Groundwater Flow, Brady Allen Johnson

Boise State University Theses and Dissertations

Riparian zones in semi-arid regions often exhibit high rates of evapotranspiration (ET) in spite of low soil moisture content due to vegetation that is able to withdraw water from shallow aquifers. This work better defines the relationship between ET and the saturated zone by comparing the observed water table drawdown to analytically modeled drawdown in fully penetrating wells of an unconfined aquifer in response to daily ET flux. ET at the Boise Hydrogeophysical Research Site or BHRS (a riparian zone in a temperate, semi arid environment) is calculated following the approach of Batra et al. (2006) but uses site …


Spatial Distribution And Evolution Of A Seasonal Snowpack In Complex Terrain: An Evaluation Of The Snodas Modeling Product, Brian Trail Anderson May 2011

Spatial Distribution And Evolution Of A Seasonal Snowpack In Complex Terrain: An Evaluation Of The Snodas Modeling Product, Brian Trail Anderson

Boise State University Theses and Dissertations

Hydrologists and water managers have been attempting to accurately estimate watershed scale snow water equivalent (SWE) for over a century. Extensive monitoring networks, remote sensing technology, and sophisticated modeling approaches have greatly improved these estimates; however, water inputs from snow in mountainous areas are still subject to considerable uncertainty due to SWE spatial variability. In an attempt to improve the understanding of physical processes and controls influencing SWE spatial variability, a field campaign to measure the spatial and temporal distribution of SWE within the Dry Creek Experimental Watershed (DCEW) was conducted during 2009 and 2010. These measurements are compared to …


Measuring The Rate Of Garnet Growth: Implications For Rb-Sr Garnet Chronology, Jessica Sousa May 2011

Measuring The Rate Of Garnet Growth: Implications For Rb-Sr Garnet Chronology, Jessica Sousa

Boise State University Theses and Dissertations

Garnet growth rates have provided valuable information for understanding the rates of tectonometamorphic processes. In theory, during its growth, garnet records the decay of 87Rb within a rock matrix as steadily increasing 87Sr/86Sr from core to rim. By measuring the Sr isotopic zoning within garnet and matrix Rb/Sr and 87Sr/86Sr, the rate of garnet growth can be determined. To test this, we used ID-TIMS to measure Rb-Sr data for five samples from three major orogenic belts: central New England, southernmost Chile, and western Italian Alps. These new data introduce two major difficulties encountered using …


A Comparison Of Two Open Source Lidar Surface Classification Algorithms, Wade T. Tinkham, Hongyu Huang, Alistair M.S. Smith, Rupesh Shrestha, Michael J. Falkowski, Andrew T. Hudak, Timothy E. Link, Nancy F. Glenn, Danny G. Marks Mar 2011

A Comparison Of Two Open Source Lidar Surface Classification Algorithms, Wade T. Tinkham, Hongyu Huang, Alistair M.S. Smith, Rupesh Shrestha, Michael J. Falkowski, Andrew T. Hudak, Timothy E. Link, Nancy F. Glenn, Danny G. Marks

Nancy Glenn

With the progression of LiDAR (Light Detection and Ranging) towards a mainstream resource management tool, it has become necessary to understand how best to process and analyze the data. While most ground surface identification algorithms remain proprietary and have high purchase costs; a few are openly available, free to use, and are supported by published results. Two of the latter are the multiscale curvature classification and the Boise Center Aerospace Laboratory LiDAR (BCAL) algorithms. This study investigated the accuracy of these two algorithms (and a combination of the two) to create a digital terrain model from a raw LiDAR point …


Taxonomy, Nomenclature, And Evolution Of The Early Schubertellid Fusulinids, Vladimir I. Davydov Mar 2011

Taxonomy, Nomenclature, And Evolution Of The Early Schubertellid Fusulinids, Vladimir I. Davydov

Geosciences Faculty Publications and Presentations

The types of the species belonging to the fusulinid genera Schubertella and Eoschubertella were examined from publications and type collections. Eoschubertella in general possesses all the features of Schubertella and therefore is a junior synonym of the latter. However, the concept of Eoschubertella best describes the genus Schubertina with its type species Schubertina curculi. Schubertina is closely related to the newly established genus Grovesella the concept of which is emended in this paper. Besides Schubertella, Schubertina, and Grovesella, the genera Mesoschubertella, Biwaella are reviewed and three new species, Grovesella nevadensis, Biwaella zhikalyaki, and Biwaella poletaevi, are described. The phylogenetic relationships …


Hammer Seismic Reflection Imaging In An Urban Environment, Lee M. Liberty Feb 2011

Hammer Seismic Reflection Imaging In An Urban Environment, Lee M. Liberty

CGISS Publications and Presentations

Subsurface characterization within urban centers is critically important for city planners, municipalities, and engineers to estimate groundwater resources, track contaminants, assess earthquake or landslide hazards, and many other similar objectives. Improving geophysical imaging methods and results, while minimizing costs, provides greater opportunities for city/project planners and geophysicists alike to take advantage of the improved characterization afforded by the particular method. Seismic reflection results can provide hydrogeologic constraints for groundwater models, provide slip rate estimates for active faults, or simply map stratigraphy to provide target depth estimate. While many traditional urban seismic transects have included the use of vibroseis sources to …