Earth Sciences Commons^™

Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler

Boise State University Theses and Dissertations

Recent studies of plant water uptake assume that soil water isotopic composition can be used to infer soil water mobility. However, the strength of the relationship between mobility and isotopic composition remains poorly constrained. In addition, many ecohydrologic investigations are restricted by low sampling frequencies and insufficient soil moisture and matric potential data to support assumptions of soil water mobility. We sampled bulk soil water every 14 to 21 days in hillslope and riparian profiles during the 2016 and 2017 growing seasons in a semi-arid watershed outside Boise, ID. We collected twig samples of four tree and shrub species concurrently. …

Exploring The Role Of Deforestation On Regional Hydroclimate In Southeast Africa: An Approach Fusing Models And Data, Megan Maksimowicz

Boise State University Theses and Dissertations

Land cover acts as the gatekeeper to incoming and outgoing energy and water fluxes at the land surface, partitioning energy and water in accordance with the vegetation type and in response to atmospheric forcings. As Land Surface Models become more complex and more capable of simulating the coupled dynamics of the land-atmosphere system in greater spatial detail, the need for accurate representation of spatial distribution of vegetation types and their dynamics through time grows.

As humans modify land cover, there are complex dynamics at play between the vegetation, the surface energy balance and the cycling of water. The resultant hydroclimatic …

Assessment Of Snow Atmosphere Forcing During Central Idaho Atmospheric Rivers, William Rudisill

Boise State University Theses and Dissertations

Atmospheric Rivers (AR) are globally occuring weather features and the primary mechanism through which water vapor moves from the tropics and subtropics towards the mid-latitudes, doing so at rates comparable to the world’s largest terrestrial rivers. AR that encounter mountains often cause extreme precipitation in the form of rain and snow, high winds, and flooding in many watersheds. They account for as much as 20-30% of cool season precipitation in the central Idaho Mountains. In the Northern Hemisphere, seasonal snow cover during Winter and Spring months is the most variable land surface component in space and time, and acts on …

From Snow To Flow: Exploring Relationships Between Snotel Ablation Curves And Peak Streamflow Timing, Kara Jane Ferguson

Boise State University Theses and Dissertations

Predictions of peak streamflow timing in snow-dominated river systems are essential for proper water management and recreational availability. This study evaluates historic snow and streamflow data from 14 river basins throughout Idaho to investigate the relationship between snowmelt timing at SNOw TELemetry (SNOTEL) sites and peak streamflow within each basin. The goal is to provide a simple operational tool that estimates the probability of peak streamflow occurring within a certain number of days as ablation progresses from 0 to 100% melted. For individual basins we evaluate meltout levels in increments of 10% from each SNOTEL site and use a probabilistic …

Tephra From The 3 March 2015 Sustained Column Related To Explosive Lava Fountain Activity At Volcán Villarrica (Chile), Jeffrey B. Johnson

Geosciences Faculty Publications and Presentations

Exceptionally intense lava fountains at open conduit volcanoes are infrequent, hazardous and little-warned events. Studying their tephra falls may reveal conduit dynamics, eruption source parameters and fragmentation mechanisms. Villarrica Volcano (Southern Andes of Chile) has sustained persistent open conduit activity, associated with a dynamic lava lake since at least 1984–85. Increased seismicity and degassing in August 2014 were followed by Strombolian activity starting in February 2015 and culminated with a 1.5 km-high lava fountain on 3 March 2015. This eruption produced tephra fallout, spatter agglutination, clastogenic lavas and mixed avalanche deposits. Here we characterized for first time Villarrica's 3 March …

Identification Of Erosional Terraces On Seamounts: Implications For Interisland Connectivity And Subsidence In The Galápagos Archipelago, Darin M. Schwartz, S. Adam Soule, V. Dorsey Wanless, Meghan R. Jones

Geosciences Faculty Publications and Presentations

Shallow seamounts at ocean island hotspots and in other settings may record emergence histories in the form of submarine erosional terraces. Exposure histories are valuable for constraining paleo-elevations and sea levels in the absence of more traditional markers, such as drowned coral reefs. However, similar features can also be produced through primary volcanic processes, which complicate the use of terraced seamounts as an indicator of paleo-shorelines. In the western Galápagos Archipelago, we utilize newly collected bathymetry along with seafloor observations from human-occupied submersibles to document the location and depth of erosional terraces on seamounts near the islands of Santiago, Santa …

Eleven Years Of Mountain Weather, Snow, Soil Moisture And Streamflow Data From The Rain–Snow Transition Zone – The Johnston Draw Catchment, Reynolds Creek Experimental Watershed And Critical Zone Observatory, Usa, James P. Mcnamara

Geosciences Faculty Publications and Presentations

Detailed hydrometeorological data from the rain-to-snow transition zone in mountain regions are limited. As the climate warms, the transition from rain to snow is moving to higher elevations, and these changes are altering the timing of downslope water delivery. To understand how these changes impact hydrological and biological processes in this climatologically sensitive region, detailed observations from the rain-to-snow transition zone are required. We present a complete hydrometeorological dataset for water years 2004 through 2014 for a watershed that spans the rain-to-snow transition zone (https://doi.org/10.15482/usda.adc/1402076). The Johnston Draw watershed (1.8km²), ranging from 1497 to 1869m in elevation, is …

Hyporheic Source And Sink Of Nitrous Oxide, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Alessandra Marzadri, Daniele Tonina

Geosciences Faculty Publications and Presentations

Nitrous oxide (N₂O) is a potent greenhouse gas with an estimated 10% of anthropogenic N₂O coming from the hyporheic zone of streams and rivers. However, difficulty in making accurate fine-scale field measurements has prevented detailed understanding of the processes of N₂O production and emission at the bedform and flowline scales. Using large-scale, replicated flume experiments that employed high-density chemical concentration measurements, we have been able to refine the current conceptualization of N₂O production, consumption, and emission from the hyporheic zone. We present a predictive model based on a Damköhler-type transformation (τ̃) in …

Single-Station Seismo-Acoustic Monitoring Of Nyiragongo's Lava Lake Activity (D.R. Congo), Jeffrey B. Johnson

Geosciences Faculty Publications and Presentations

Since its last effusive eruption in 2002, Nyiragongo has been an open-vent volcano characterized by the world's largest persistent lava lake. This lava lake provides a unique opportunity to detect pressure change in the magmatic system by analyzing its level fluctuations. We demonstrate that this information is contained in the seismic and infrasound signals generated by the lava lake's activity. The continuous seismo-acoustic monitoring permits quantification of lava lake dynamics, which is analyzed retrospectively to identify periods of volcanic unrest. Synchronous, high-resolution satellite SAR (Synthetic Aperture Radar) images are used to constrain lava lake level by measuring the length of …

Infrasound Tornillos Produced By Volcán Cotopaxi’S Deep Crater, J. B. Johnson, M. C. Ruiz, H. D. Ortiz, L. M. Watson, G. Viracucha, P. Ramon, M. Almeida

CGISS Publications and Presentations

We characterize and interpret a new type of infrasound signal originating from the summit of Volcán Cotopaxi (Ecuador) that was primarily observed between September 2015 and March 2016, following the 2015 eruptive period. This infrasound waveform is a slowly decaying sinusoid with exceptional low-frequency (f_p = 0.2 Hz) and high quality factor (Q = ~10) and resembles the shape of tornillo seismic waveforms. The repeating events, occurring about once per day in early 2016, are stable in frequency content, and we attribute them to excitation of a vertical-walled crater, with radius of about 125mand length of 300 …

Seismic Imaging Of The Main Frontal Thrust In Nepal Reveals A Shallow Décollement And Blind Thrusting, Rafael V. Almeida, Judith Hubbard, Lee Liberty, Anna Foster, Soma Nath Sapkota

CGISS Publications and Presentations

Because great earthquakes in the Himalaya have an average recurrence interval exceeding 500 yr, most of what we know about past earthquakes comes from paleoseismology and tectonic geomorphology studies of the youngest fault system there, the Main Frontal Thrust (MFT). However, these data are sparse relative to fault segmentation and length, and interpretations are often hard to validate in the absence of information about fault geometry. Here, we image the upper two km of strata in the vicinity of the fault tip of the MFT in central Nepal (around the town of Bardibas) applying a pre-stack migration approach to two …

Landscape Analysis Of Soil Methane Flux Across Complex Terrain, Kendra E. Kaiser, Brian L. Mcglynn, John E. Dore

Geosciences Faculty Publications and Presentations

Relationships between methane (CH₄) fluxes and environmental conditions have been extensively explored in saturated soils, while research has been less prevalent in aerated soils because of the relatively small magnitudes of CH₄ fluxes that occur in dry soils. Our study builds on previous carbon cycle research at Tenderfoot Creek Experimental Forest, Montana, to identify how environmental conditions reflected by topographic metrics can be leveraged to estimate watershed scale CH₄ fluxes from point scale measurements. Here, we measured soil CH₄ concentrations and fluxes across a range of landscape positions (7 riparian, 25 upland), utilizing topographic and …

Steering Operational Synergies In Terrestrial Observation Networks: Opportunity For Advancing Earth System Dynamics Modelling, Roland Baatz, Pamela L. Sullivan, Li Li, Samantha R. Weintraub, Henry W. Loescher, Michael Mirtl, Peter M. Groffman, Diana H. Wall, Michael Young, Tim White, Hang Wen, Steffen Zacharias, Ingolf Kühn, Jianwu Tang, Jérôme Gaillardet, Isabelle Braud, Alejandro N. Flores, Praveen Kumar, Henry Lin, Teamrat Ghezzehei, Julia Jones, Henry L. Gholz, Harry Vereecken, Kris Van Looy

Geosciences Faculty Publications and Presentations

Advancing our understanding of Earth system dynamics (ESD) depends on the development of models and other analytical tools that apply physical, biological, and chemical data. This ambition to increase understanding and develop models of ESD based on site observations was the stimulus for creating the networks of Long-Term Ecological Research (LTER), Critical Zone Observatories (CZOs), and others. We organized a survey, the results of which identified pressing gaps in data availability from these networks, in particular for the future development and evaluation of models that represent ESD processes, and provide insights for improvement in both data collection and model integration. …

Lava, Ash Flows, Mudslides And Nasty Gases: Good Reasons To Respect Volcanoes, Brittany Brand

Geosciences Faculty Publications and Presentations

Volcanoes are beautiful and awe-inspiring, but the ongoing eruption of Kilauea on Hawaii’s Big Island is showing how dangerous these events can be. So far this event has destroyed dozens of homes and displaced hundreds of people, but no deaths or serious injuries have been reported. Other volcanic eruptions have had deadlier impacts.

Local, Regional, And Remote Seismo‐Acoustic Observations Of The April 2015 Vei 4 Eruption Of Calbuco Volcano, Chile, Robin S. Matoza, David Fee, David N. Green, Alexis Le Pichon, Julien Vergoz, Matthew M. Haney, T. Dylan Mikesell, Luis Franco, O. Alberto Valderrama, Megan R. Kelley, Kathleen Mckee, Lars Ceranna

CGISS Publications and Presentations

The two major explosive phases of the 22–23 April 2015 eruption of Calbuco volcano, Chile, produced powerful seismicity and infrasound. The eruption was recorded on seismo-acoustic stations out to 1,540 km and on five stations (IS02, IS08, IS09, IS27, and IS49) of the International Monitoring System (IMS) infrasound network at distances from 1,525 to 5,122 km. The remote IMS infrasound stations provide an accurate explosion chronology consistent with the regional and local seismo-acoustic data and with previous studies of lightning and plume observations. We use the IMS network to detect and locate the eruption signals using a brute-force, grid-search, cross-bearings …

Estimation Of Porosity And Water Saturation In Dual-Porosity Pyroclastic Deposits From Joint Analysis Of Compression, Shear, And Electromagnetic Velocities, Andrew C. Gase, John H. Bradford, Brittany D. Brand

Geosciences Faculty Publications and Presentations

In situ measurements of porosity and water saturation of pyroclastic deposits have the potential to improve interpretations of geology and hydrology in volcanic regions, and to provide more accurate estimates of dense rock equivalent for volcanic eruptions. However, rock-property models must consider the dual-porosity structure of pyroclastic deposits (i.e., vesicles within pumices and intergranular pores). Vesicularity, intergranular porosity, and water saturation all affect the density, elasticity, and dielectric properties of pyroclastic materials, which control seismic and electromagnetic velocities. The data from active seismic and ground-penetrating radar (GPR) techniques may improve porosity and water saturation estimation if the responses of seismic …

Multi-Channel Ground-Penetrating Radar For The Continuous Quantification Of Snow And Firn Density, Depth, And Accumulation, Tate Meehan

Boise State University Theses and Dissertations

A priority of ice sheet surface mass balance (SMB) prediction is ascertaining the surface density and annual snow accumulation. These forcing data are inputs for firn density models and can be used to inform remotely sensed ice sheet surface processes and to assess Regional Climate Model (RCM) skill. The Greenland Traverse for Accumulation and Climate Studies (GreenTrACS) retrieved 16 shallow firn cores and dug 42 snow pits along the Western percolation zone of the Greenland Ice Sheet (GrIS) during May and June of 2016 and 2017. I deployed and maintained a multi-channel 500 MHz ground-penetrating radar in a multi-offset configuration …

Using Landlab, A Fine Scale Biogeography Model, To Measure The Sustainability Of Semi-Arid Vegetation In A Changing Climate, Lucy Gelb

Boise State University Theses and Dissertations

The distribution of vegetation in water-limited ecosystems is a product of complex and nonlinear interactions between climatic forcings (e.g., precipitation, temperature, solar radiation) and the underlying geomorphic template, which includes topography, geology, and soils. Changes in climate, particularly in precipitation and temperature, can dramatically alter the organization of vegetation. This is especially true in ecotones such as our area of study: the semi-arid transition between Great Basin shrub-steppe ecosystems and the coniferous forests of the Northern Rockies. Understanding and predicting how the spatial composition of terrestrial vegetation communities will change in these ecosystems is critical to predicting important future landscape …

Geochemical Dynamics And Nitrous Oxide Release From The Hyporheic Zone Of Streams, Annika Marie Quick

Boise State University Theses and Dissertations

The hyporheic zones of streams and rivers, consisting of the sediments beneath and immediately adjacent to the stream channel, are an important site of geochemical processing. Due to the difficulty of measuring these geochemical processes in the hyporheic zone in situ with meaningful spatial and temporal resolution, we conducted multiple column and large-scale flume experiments to model 1D and 2D hyporheic flow paths and observed important geochemical reactions, including the production and consumption of nitrous oxide (N₂O). N₂O is a significant greenhouse gas, but the controls on its emissions from streams are poorly constrained. We describe …

Diverse Eruptive Activity Revealed By Acoustic And Electromagnetic Observations Of The 14 July 2013 Intense Vulcanian Eruption Of Tungurahua Volcano, Ecuador, J. F. Anderson, J. B. Johnson, A. L. Steele, M. C. Ruiz, B. D. Brand

CGISS Publications and Presentations

During the powerful July 2013 eruption of Tungurahua volcano, Ecuador, we recorded exceptionally high amplitude, long‐period infrasound (1,600‐Pa peak‐to‐peak amplitude, 5.5‐s period) on sensors within 2km of the vent alongside electromagnetic signals from volcanic lightning serendipitously captured as interference. This explosion was one of Tungurahua's most powerful vulcanian eruptions since recent activity began in 1999, and its acoustic wave is among the most powerful volcanic infrasound ever recorded anywhere. We use these data to quantify erupted volume from the main explosion and to classify postexplosive degassing into distinct emission styles. Additionally, we demonstrate a highly effective method of recording lightning‐related …

Ice Core Records Of West Greenland Melt And Climate Forcing, H.P. Marshall, T. Meehan

CGISS Publications and Presentations

Remote sensing observations and climate models indicate that the Greenland Ice Sheet (GrIS) has been losing mass since the late 1990s, mostly due to enhanced surface melting from rising summer temperatures. However, in situ observational records of GrIS melt rates over recent decades are rare. Here we develop a record of frozen meltwater in the west GrIS percolation zone preserved in seven firn cores. Quantifying ice layer distribution as a melt feature percentage (MFP), we find significant increases in MFP in the southernmost five cores over the past 50 years to unprecedented modern levels (since 1550 CE). Annual to decadal …

Forecasting The Eruption Of An Open‐Vent Volcano Using Resonant Infrasound Tones, Jeffrey B. Johnson, Leighton M. Watson, Jose L. Palma, Eric M. Dunham, Jacob F. Anderson

CGISS Publications and Presentations

Open‐vent volcanic systems with active degassing are particularly effective at producing infrasound that exhibits resonant tones controlled by the geometry of the volcano's crater. Changes in the infrasound character can thus provide constraints on a crater's lava level, which may vary dynamically in the lead‐up to an eruption. Here we show that the increasing frequency content and damping characteristics of the resonant infrasound at Volcán Villarrica (Chile) relate to lava lake position in its crater/conduit preceding its 2015 eruption. We model the acoustic response of Villarrica's crater to determine that the lake began to rise on 27 February and reached …

Spatial And Temporal Dynamics Of Dissolved Oxygen Concentrations And Bioactivity In The Hyporheic Zone, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Daniele Tonina

Geosciences Faculty Publications and Presentations

Dissolved oxygen (DO) concentrations and consumption rates are primary indicators of heterotrophic respiration and redox conditions in the hyporheic zone (HZ). Due to the complexity of hyporheic flow and interactions between hyporheic hydraulics and the biogeochemical processes, a detailed, mechanistic, and predictive understanding of the biogeochemical activity in the HZ has not yet been developed. Previous studies of microbial activity in the HZ have treated the metabolic DO consumption rate constant (K_DO) as a temporally fixed and spatially homogeneous property that is determined primarily by the concentration of bioavailable carbon. These studies have generally treated bioactivity as temporally …

Geologic Framework Of The Fang Hot Springs Area With Emphasis On Structure, Hydrology, And Geothermal Development, Chiang Mai Provence, Northern Thailand, Spencer H. Wood, Pichet Kaewsomwang, Fongsaward Suvagondha Singharajwarapan

Geosciences Faculty Publications and Presentations

Geologic mapping, a magnetotelluric survey, well data, and earlier reports are integrated to guide further development of the Fang geothermal system. The Fang Hot Springs originally flowed ~ 20 l s⁻¹ of 90–99 °C water from a 10-hectare area of crystal- line rocks presumed to be of Triassic age. Four wells 92–500 m deep now flow ~ 20 l s⁻¹ of 110–115 °C water and generate 115–250 kWe from the 1989 Ormat binary power plant. Wells are not pumped nor is the spent water re-injected. Temperatures of 130 °C occur in some wells and water chemistry indicates reservoir …

One Diamictite And Two Rifts: Stratigraphy And Geochronology Of The Gataga Mountain Of Northern British Columbia, Athena Eyster, Filippo Ferri, Mark D. Schmitz, Francis A. Macdonald

Geosciences Faculty Publications and Presentations

Neoproterozoic glacial diamictites and rift-related volcanics are preserved throughout the North American Cordillera, yet the nature and timing of both glaciation and rifting are poorly constrained. New geochronological, geochemical, and stratigraphic data from the Cryogenian Gataga volcanics and bounding units at Gataga Mountain, in the Kechika Trough of northern British Columbia, better constrain the age of these rift-related volcanics and suggest that they erupted during glaciation. At Gataga Mountain, three informal sequences are exposed; a basal quartzite, the Gataga volcanics, and an overlying mixed carbonate-siliciclastic succession. The basal quartzite is dominated by cross-bedded sandstone with an intertidal facies assemblage including …

Geothermal Play Fairway Analysis, Phase 3: A Provisional Conceptual Model Of The Camas Prairie, Snake River Plain, Idaho, Lee M. Liberty

CGISS Publications and Presentations

The Snake River Plain (SRP) Geothermal Play Fairway Analysis team identified two regions of interest during Phase 2 studies: the western SRP near Mountain Home, Idaho and Camas Prairie, Idaho. New geological, geochemical, and geophysical (gravity, magnetic, MT, seismic) studies of both areas led to a focus on Camas Prairie for validation during Phase 3. Camas Prairie is an EW-trending half-graben bounded on the north by the Idaho Batholith and on the south by the Mount Bennett Hills. Camas Prairie is bisected by a major NW-trending fault system (The Pothole fault) that separates NW-trending faults to east from ENE-trending faults …

Assessment Of Ground-Based And Aerial Cloud Seeding Using Trace Chemistry, James M. Fisher, Marion L. Lytle, Shawn G. Benner

Geosciences Faculty Publications and Presentations

Targeting seedable clouds with silver iodide in complex terrain adds considerable uncertainty in weather modification studies. This study explores the geographic and temporal distribution of silver iodide associated with an active cloud seeding program in central Idaho snowpack using trace chemistry. Over 4,000 snow samples were analyzed for the presence of a cloud seeding silver iodide (AgI) signature over two winter seasons. The results indicate the following. (1) At sites within 70 km of AgI sources, silver enrichments were detected at 88% of cases involving seeding efforts from ground generators, but none from aircraft seeded cases. (2) Real-time snow collection …

Petrology And Geochronology Of Metamorphic Zircon, Matthew J. Kohn, Nigel M. Kelly

Geosciences Faculty Publications and Presentations

Zircon is unusually well suited for investigating metamorphic processes because it is readily analyzed for U‐Pb ages, it harbors diverse mineral inclusions, and its chemistry can be linked to metamorphic parageneses and P‐T paths. Metamorphic zircon chemistry and ages are relevant only at the sub‐grain micron scale, and consequently many analytical methods, such as depth profiling, have been developed to exploit such spatially resolute infor­mation. Here we review how metamorphic zircon grows, and how its chemistry and inclusion assemblages may be used to link the age of a zircon domain to its metamorphic P‐T condition. Domain‐specific ages and inclusion assemblages …

A Geophysical Characterization Of The Structural Framework Of The Camas Prairie Geothermal System, Southcentral Idaho, Lee Liberty

CGISS Publications and Presentations

Play Fairway Analysis methods, utilizing existing geologic, thermal, geochemical, and geophysical data were employed in an initial assessment of geothermal resources in the Snake River Plain. These efforts identified the Camas Prairie in southcentral Idaho as a region with elevated resource potential. Subsequent efforts included structural and geophysical data collection to identify the most favorable structural settings for exploiting resources in the valley. The present work involved high-resolution gravity, magnetic, magnetotellurics (MT), field mapping, and seismic surveys to further characterize the system and target sites for exploration drilling around Barron’s Hot Springs (BHS) in the southwest part of the valley. …

Combined Assimilation Of Satellite Precipitation And Soil Moisture: A Case Study Using Trmm And Smos Data, Liao-Fan Lin, Ardeshir M. Ebtehaj, Alejandro N. Flores, Satish Bastola, Rafael L. Bras

Geosciences Faculty Publications and Presentations

This paper presents a framework that enables simultaneous assimilation of satellite precipitation and soil moisture observations into the coupled Weather Research and Forecasting (WRF) and Noah land surface model through variational approaches. The authors tested the framework by assimilating precipitation data from the Tropical Rainfall Measuring Mission (TRMM) and soil moisture data from the Soil Moisture Ocean Salinity (SMOS) satellite. The results show that assimilation of both TRMM and SMOS data can effectively improve the forecast skills of precipitation, top 10-cm soil moisture, and 2-m temperature and specific humidity. Within a 2-day time window, impacts of precipitation data assimilation on …