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2015

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Full-Text Articles in Physical Sciences and Mathematics

Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen Dec 2015

Unblocking Temperatures Of Viscous Remanent Magnetism In Displaced Granitic Boulders, Icicle Creek Glacial Moraines (Washington, Usa), Juliet G. Crider, Danika M. Globokar, Russ F. Burmester, Bernard A. Housen

Geology Faculty Publications

Viscous remanent magnetization (VRM) may partially overprint original magnetization in rocks displaced by geomorphic events. An established theoretical relationship between the time and temperature of acquisition of VRM and the time and temperature of demagnetization suggests that laboratory demagnetization (unblocking) of VRM can be used to estimate the displacement age of rocks. We test this hypothesis at four nested glacial moraines in the Icicle Creek drainage of central Washington, the ages of which were previously determined by cosmogenic surface exposure dating. The moraines are composed primarily of granodiorite boulders, and magnetic remanence is carried dominantly by magnetite. Both the maximum …


U.S. Drought Monitor, December 22, 2015, Richard R. Heim Jr. Dec 2015

U.S. Drought Monitor, December 22, 2015, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 22, 2015 (12/22/15) 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.


Enriched Continental Flood Basalts From Depleted Mantle Melts: Modeling The Lithospheric Contamination Of Karoo Lavas From Antarctica, Jussi S. Heinonen, Arto V. Luttinen, Wendy A. Bohrson Dec 2015

Enriched Continental Flood Basalts From Depleted Mantle Melts: Modeling The Lithospheric Contamination Of Karoo Lavas From Antarctica, Jussi S. Heinonen, Arto V. Luttinen, Wendy A. Bohrson

All Faculty Scholarship for the College of the Sciences

Continental flood basalts (CFBs) represent large-scale melting events in the Earth’s upper mantle and show considerable geochemical heterogeneity that is typically linked to substantial contribution from underlying continental lithosphere. Large-scale partial melting of the cold subcontinental lithospheric mantle and the large amounts of crustal contamination suggested by traditional binary mixing or assimilation-fractional crystallization models are difficult to reconcile with the thermal and compositional characteristics of continental lithosphere, however. The well-exposed CFBs of Vestfjella, western Dronning Maud Land, Antarctica, belong to the Jurassic Karoo large igneous province and provide a prime locality to quantify mass contributions of lithospheric and sublithospheric sources …


Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner Dec 2015

Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner

Geology Faculty Publications and Presentations

This study reports the first successful statistical crossdating among many ring width time series from petrified wood, thus providing a replicable continuous annual resolution window into tree growth and environmental influences during the middle Miocene. The petrified samples, of the genus Quercus, originated at the Stinking Water (SW) locality in Oregon, a Miocene-aged exposure associated with the Columbia River Basalts. 40AR/39AR dating on pillow basalt from the locality yielded a weighted Plateau Age of 13.79 ±0.09 Ma placing the death of the trees at the end of the Langhian Stage of the Middle Miocene (15.97±0.05 to 13.65±0.05 …


A Desert In Disguise: The Resilience Of The Nebraska Sandhills, Jeff Hartman Dec 2015

A Desert In Disguise: The Resilience Of The Nebraska Sandhills, Jeff Hartman

School of Natural Resources: Dissertations, Theses, and Student Research

The Nebraska Sandhills are the largest sand dune system in the Western Hemisphere, and are unique because they remain relatively undisturbed from row crop agriculture. Research in the past two decades demonstrated that the Sandhills are dynamic on millennial timescales, switching between stabilized, vegetated states to non-vegetated, mobilized states. The Sandhills are currently stabilized, but understanding how ecological processes are altered as sand dunes transition from stabilized to mobilized states, provides insight into the thresholds, stability, and resilience of this grassland ecosystem. My research investigated the impacts of vegetation disturbances on ecological processes and the sand dune surface stability. For …


Phosphorus Release Potential Of Agricultural Soils Of The United States, Rebecca A. Young Dec 2015

Phosphorus Release Potential Of Agricultural Soils Of The United States, Rebecca A. Young

School of Natural Resources: Dissertations, Theses, and Student Research

Phosphorus (P) is one of the leading causes of surface water quality decline in the United States, leading to algal blooms and hypoxia in lakes and streams. Decreasing conservation funds dictate that agencies such as the Natural Resources Conservation Service, maximizes its effectiveness and efficiency in implementing practices to address P management and runoff on agricultural lands. Additional information on P behavior in soil is needed to improve P management plans to reduce pollution risk at the watershed, farm, and field scales. This research focuses on the development of total soil P release models, to be included into assessment and …


Coarse Bedload Routing And Dispersion Through Tributary Confluences, Kurt Imhoff, Andrew C. Wilcox Dec 2015

Coarse Bedload Routing And Dispersion Through Tributary Confluences, Kurt Imhoff, Andrew C. Wilcox

Geosciences Faculty Publications

Sediment routing fundamentally influences channel morphology and propagation of disturbances. However, the transport and storage of bedload particles in headwater channel confluences, which may be significant nodes of the channel network in terms of sediment routing, morphology, and habitat, is poorly understood. To characterize routing processes through confluences of headwater channels, we investigate how sediment routing patterns through headwater confluences compare to those described in low-gradient gravel bed river systems, and how confluences affect the dispersive behavior of coarse bedload particles compared to non-confluence reaches. We address these questions with a field tracer experiment using passive-integrated transponder and radio-frequency identification …


Linear Trend Detection In Serially Dependent Hydrometeorological Data Based On A Variance Correction Spearman Rho Method, Wenpeng Weng, Yuanfang Chen, Stefan Becker, Bo Liu Dec 2015

Linear Trend Detection In Serially Dependent Hydrometeorological Data Based On A Variance Correction Spearman Rho Method, Wenpeng Weng, Yuanfang Chen, Stefan Becker, Bo Liu

Publications and Research

Hydrometeorological data are commonly serially dependent and thereby deviate from the assumption of independence that underlies the Spearman rho trend test. The presence of autocorrelation will influence the significance of observed trends. Specifically, the positive autocorrelation inflates Type І errors, while it deflates the power of trend detection in some cases. To address this issue, we derive a theoretical formula and recommend an appropriate empirical formula to calculate the rho variance of dependent series. The proposed procedure of the variance correction for the Spearman rho method is capable of mitigating the effect of autocorrelation on both, Type І error and …


U.S. Drought Monitor, December 15, 2015, Richard Tinker Dec 2015

U.S. Drought Monitor, December 15, 2015, Richard Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 15, 2015 (12/15/15) 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.


A Seismic Transect Across West Antarctica: Evidence For Mantle Thermal Anomalies Beneath The Bentley Subglacial Trench And The Marie Byrd Land Dome, Andrew J. Lloyd, Douglas A. Wiens, Andrew A. Nyblade, Sridhar Anandakrishnan, Richard C. Aster, Audrey D. Huerta, Terry J. Wilson, Ian W. D. Dalziel, Patrick J. Shore, Dapeng Zhao Dec 2015

A Seismic Transect Across West Antarctica: Evidence For Mantle Thermal Anomalies Beneath The Bentley Subglacial Trench And The Marie Byrd Land Dome, Andrew J. Lloyd, Douglas A. Wiens, Andrew A. Nyblade, Sridhar Anandakrishnan, Richard C. Aster, Audrey D. Huerta, Terry J. Wilson, Ian W. D. Dalziel, Patrick J. Shore, Dapeng Zhao

All Faculty Scholarship for the College of the Sciences

West Antarctica consists of several tectonically diverse terranes, including the West Antarctic Rift System, a topographic low region of extended continental crust. In contrast, the adjacent Marie Byrd Land and Ellsworth-Whitmore mountains crustal blocks are on average over 1km higher, with the former dominated by polygenetic shield and stratovolcanoes protruding through the West Antarctic ice sheet and the latter having a Precambrian basement. The upper mantle structure of these regions is important for inferring the geologic history and tectonic processes, as well as the influence of the solid earth on ice sheet dynamics. Yet this structure is poorly constrained due …


A Preliminary Assessment Of Water Partitioning And Ecohydrological Coupling In Northern Headwaters Using Stable Isotopes And Conceptual Runoff Models, James P. Mcnamara Dec 2015

A Preliminary Assessment Of Water Partitioning And Ecohydrological Coupling In Northern Headwaters Using Stable Isotopes And Conceptual Runoff Models, James P. Mcnamara

Geosciences Faculty Publications and Presentations

We combined a conceptual rainfall-runoff model and input–output relationships of stable isotopes to understand ecohydrological influences on hydrological partitioning in snow-influenced northern catchments. Six sites in Sweden (Krycklan), Canada (Wolf Creek; Baker Creek; Dorset), Scotland (Girnock) and the USA (Dry Creek) span moisture and energy gradients found at high latitudes. A meta-analysis was carried out using the Hydrologiska Byråns Vattenbalansavdelning (HBV) model to estimate the main storage changes characterizing annual water balances. Annual snowpack storage importance was ranked as Wolf Creek > Krycklan > Dorset > Baker Creek > Dry Creek > Girnock. The subsequent rate and longevity of melt were reflected in calibrated parameters …


Mobile Mud Dynamics In The East China Sea Elucidated Using 210pb, 137cs, 7be, And 234th As Tracers, Jinlong Wang, Jinzhou Du, Mark Baskaran, Jing Zhang Dec 2015

Mobile Mud Dynamics In The East China Sea Elucidated Using 210pb, 137cs, 7be, And 234th As Tracers, Jinlong Wang, Jinzhou Du, Mark Baskaran, Jing Zhang

Environmental Science and Geology Faculty Research Publications

“Mobile mud” (MM), which has fine grain size distribution (>90% clay + silt, and <5% sand) and high porosity (≥0.50), plays an important role in the biogeochemical cycles in the estuarine areas and the inshore shelf. A suite of MM samples from the coastal area of the East China Sea (ECS) was collected in spring and summer of 2011 to observe their spatial and temporal distribution, grain size, and radionuclides concentrations. The MM thickness ranged from 0.5 to 11 cm (average: 2.2 cm (May) and 3.9 cm (August)). The thick mud layer is mainly distributed along the coast, with an area of 2.2 × 104 km2 in May and 1.5 × 104 km2 in August, with corresponding masses of 8.8 × 108 and 7.8 × 108 t, respectively. The estimated masses of MM are considerably larger than the annual sediment discharge mass of the Changjiang River. The distribution of 137Cs inventories in MM indicates that 137Cs can be effectively utilized as a transport tracer of MM in the river‐dominated estuaries and coastal areas. The higher inventories of 7Be in MM in the river mouth in spring are attributed to higher depositional flux and higher sediment discharge. The ratio of the MM inventory of 234Thex/production in the overlying water column of >2.5 in south inshore indicates that the sediment focusing resulted in the increased mass flux. The residence time of MM is estimated as 3–6 years both by mass balance of MM and 210Pbex in MM.


Inverse Modelling Of The Reversely Magnetized, Shallow Plumbing System Hosting Oil Reservoirs Of The Auca Mahuida Volcano (Payeina Retroarc, Neuquén Basin, Argentina), John Paine, Riccardo De Ritis, Guido Ventura, Mariana Longo, Dhananjay Ravat, Fabio Speranza, Massimo Chiappini Dec 2015

Inverse Modelling Of The Reversely Magnetized, Shallow Plumbing System Hosting Oil Reservoirs Of The Auca Mahuida Volcano (Payeina Retroarc, Neuquén Basin, Argentina), John Paine, Riccardo De Ritis, Guido Ventura, Mariana Longo, Dhananjay Ravat, Fabio Speranza, Massimo Chiappini

Earth and Environmental Sciences Faculty Publications

The Auca Mahuida volcano (2.03–0.88 Ma) located east of the Andean thrust front in the Neuquén basin (Argentina) hosts an oil system of thermogenic origin and is affected by the NW–SE striking-faults. Intrusive bodies and the underlying Jurassic sediments constitute the reservoir rocks. Aeromagnetic data collected in the Auca Mahuida area detected multiple dipolar magnetic anomalies, many of which have reverse polarity. Palaeomagnetic measurements on rock samples collected in the field together with available age determinations indicate that the reversely magnetized sources were mainly emplaced during the Matuyama reverse polarity chron while the normal polarity sources were emplaced during the …


Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber Dec 2015

Elevation Promotes Long-Term Survival Of Pinus Elliottii Var. Densa, A Foundation Species Of The Endangered Pine Rockland Ecosystem In The Florida Keys, Grant L. Harley, Justin T. Maxwell, George T. Raber

Faculty Publications

The pine rockland community in southern Florida, which supports numerous state- and federally listed flora and fauna species, is considered endangered. Without its foundation species, Pinus elliottii var. densa, habitat and species diversity are lost to tropical hardwood hammock. Here, we investigate the landscape factors that contribute to the long-term persistence of pine rocklands on the 2 islands that contain the largest remaining habitat in the Florida Keys: Big Pine Key and No Name Key. Plot-level biophysical data and island-scale remotely sensed vegetation data were collected from pine rockland savannas and examined with multi-dimensional analysis. On both islands, vegetation …


Mitigating N2o Emissions From Soil: From Patching Leaks To Transformative Action, C. Decock, Juhwan Lee, M. Necpalova, Engil Isadora Pujol Pereira, D. M. Tendall, Johan Six Dec 2015

Mitigating N2o Emissions From Soil: From Patching Leaks To Transformative Action, C. Decock, Juhwan Lee, M. Necpalova, Engil Isadora Pujol Pereira, D. M. Tendall, Johan Six

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Further progress in understanding and mitigating N2O emissions from soil lies within transdisciplinary research that reaches across spatial scales and takes an ambitious look into the future.


Development And Evaluation Of A Multi-Year Fractional Surface Water Data Set Derived From Active/Passive Microwave Remote Sensing Data, Ronny Schroeder, Kyle C. Mcdonald, Bruce D. Chapman, Katherine Jensen, Erika Podest, Zachary D. Tessler, Theodore J. Bohn, Reiner Zimmermann Dec 2015

Development And Evaluation Of A Multi-Year Fractional Surface Water Data Set Derived From Active/Passive Microwave Remote Sensing Data, Ronny Schroeder, Kyle C. Mcdonald, Bruce D. Chapman, Katherine Jensen, Erika Podest, Zachary D. Tessler, Theodore J. Bohn, Reiner Zimmermann

Publications and Research

The sensitivity of Earth’s wetlands to observed shifts in global precipitation and temperature patterns and their ability to produce large quantities of methane gas are key global change questions. We present a microwave satellite-based approach for mapping fractional surface water (FW) globally at 25-km resolution. The approach employs a land cover-supported, atmospherically-corrected dynamic mixture model applied to 20+ years (1992–2013) of combined, daily, passive/active microwave remote sensing data. The resulting product, known as Surface WAter Microwave Product Series (SWAMPS), shows strong microwave sensitivity to sub-grid scale open water and inundated wetlands comprising open plant canopies. SWAMPS’ FW compares favorably (R2 …


A Review Of Solar And Visible Light Active Tio2 Photocatalysis For Treating Bacteria, Cyanotoxins And Contaminants Of Emerging Concern, Rachel Fagan, Declan Mccormack, Suresh Pillai, Dionysios Dionysiou Dec 2015

A Review Of Solar And Visible Light Active Tio2 Photocatalysis For Treating Bacteria, Cyanotoxins And Contaminants Of Emerging Concern, Rachel Fagan, Declan Mccormack, Suresh Pillai, Dionysios Dionysiou

Articles

Research into the development of solar and visible light active photocatalysts has been significantly increased in recent years due to its wide range of applications in treating contaminants of emerging concern (CECs), endocrine disrupting compounds (EDCs), bacteria and cyanotoxins. Solar photocatalysis is found to be highly effective in treating a wide range of CECs from sources such as pharmaceuticals, steroids, antibiotics, phthalates, disinfectants, pesticides, fragrances (musk), preservatives and additives. Similarly, a number of EDCs including polycyclic aromatic hydrocarbons (PAHs), alkylphenols (APs), bisphenol A (BPA), organotins (OTs), volatile organic compounds (VOCs), natural and synthetic estrogenic and androgenic chemicals, pesticides, and heavy …


Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes Dec 2015

Mantle-Derived Helium In Hot Springs Of The Cordillera Blanca, Peru: Implications For Mantle-To-Crust Fluid Transfer In A Flat-Slab Subduction Setting, Dennis L. Newell, Micah J. Jessup, David R. Hilton, Colin Shaw, Cameron Hughes

Geosciences Faculty Publications

Fault-controlled hot springs in the Cordillera Blanca, Peru provide geochemical evidence of mantle-derived fluids in a modern flat-slab subduction setting. The Cordillera Blanca is an ~200km-long mountain range that contains the highest peaks in the Peruvian Andes, located in an amagmatic reach of the Andean arc. The Cordillera Blanca detachment defines the southwestern edge of the range and records a progression of top-down-to-the-west ductile shear to brittle normal faulting since ~5Ma. Hot springs, recording temperatures up to 78°C, issue along this fault zone and are CO2-rich, near neutral, alkaline-chloride to alkaline-carbonate waters, with elevated trace metal contents including …


Rainfall Accumulation In Clarksville, Tennessee 2015093 To 2015121, Jessica Mae Bender Dec 2015

Rainfall Accumulation In Clarksville, Tennessee 2015093 To 2015121, Jessica Mae Bender

Graduate Student Publications and Other Works

The purpose of this project was to collect rainfall samples and record the data in such a way that tested a hypothesis. My hypothesis is that the area in Clarksville, Tennessee where the samples are collected will collect up to eight inches of rain for the thirteen week time span.


Estimation Of Deep Drainage Differences Between Till And No-Till Irrigated Agriculture, Justin P. Gibson Dec 2015

Estimation Of Deep Drainage Differences Between Till And No-Till Irrigated Agriculture, Justin P. Gibson

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

Deep drainage was monitored under two center pivot irrigation sites located in south-central Nebraska during the 2013, and part of the 2014, growing seasons. Both fields underwent similar land management except for tillage practice: no-till in one and disk till in the other. Long term deep drainage rates were also estimated from chemical analysis of extracted soil cores, with the aid of the chloride mass balance equation. Mechanisms underpinning differences in deep drainage between the two fields were investigated through the use of unsaturated zone numerical modeling.

Deep drainage estimates from field monitoring indicated that a greater amount of deep …


Mycorrhizal Roots In A Temperate Forest Take Up Organic Nitrogen From 13c- And 15n-Labeled Organic Matter, Matthew A. Vadeboncoeur, Andrew P. Ouimette, Erik A. Hobbie Dec 2015

Mycorrhizal Roots In A Temperate Forest Take Up Organic Nitrogen From 13c- And 15n-Labeled Organic Matter, Matthew A. Vadeboncoeur, Andrew P. Ouimette, Erik A. Hobbie

Earth Systems Research Center

Background and Aims

The importance of the uptake of nitrogen in organic form by plants and mycorrhizal fungi has been demonstrated in various ecosystems including temperate forests. However, in previous experiments, isotopically labeled amino acids were often added to soils in concentrations that may be higher than those normally available to roots and mycorrhizal hyphae in situ, and these high concentrations could contribute to exaggerated uptake.

Methods

We used an experimental approach in which we added 13C-labeled and 15N-labeled whole cells to root-ingrowth cores, allowing proteolytic enzymes to release labeled organic nitrogen at a natural rate, as …


The Volta Grande Do Xingu: Reconstruction Of Past Environments And Forecasting Of Future Scenarios Of A Unique Amazonian Fluvial Landscape, A. O. Sawakuchi, G. A. Hartmann, H. O. Sawakuchi, F. N. Pupim, D. J. Bertassoli, M. Parra, J. L. Antinao, L. M. Sousa, M. H. Sabaj Pérez, P. E. Oliveira, R. A. Santos, J. F. Savian, C. H. Grohmann, V. B. Medeiros, Michael M. Mcglue, D. C. Bicudo, S. B. Faustino Dec 2015

The Volta Grande Do Xingu: Reconstruction Of Past Environments And Forecasting Of Future Scenarios Of A Unique Amazonian Fluvial Landscape, A. O. Sawakuchi, G. A. Hartmann, H. O. Sawakuchi, F. N. Pupim, D. J. Bertassoli, M. Parra, J. L. Antinao, L. M. Sousa, M. H. Sabaj Pérez, P. E. Oliveira, R. A. Santos, J. F. Savian, C. H. Grohmann, V. B. Medeiros, Michael M. Mcglue, D. C. Bicudo, S. B. Faustino

Earth and Environmental Sciences Faculty Publications

The Xingu River is a large clearwater river in eastern Amazonia and its downstream sector, known as the Volta Grande do Xingu (“Xingu Great Bend”), is a unique fluvial landscape that plays an important role in the biodiversity, biogeochemistry and prehistoric and historic peopling of Amazonia. The sedimentary dynamics of the Xingu River in the Volta Grande and its downstream sector will be shifted in the next few years due to the construction of dams associated with the Belo Monte hydropower project. Impacts on river biodiversity and carbon cycling are anticipated, especially due to likely changes in sedimentation and riverbed …


Geosciences Newsletter - 2015, Department Of Geosciences Dec 2015

Geosciences Newsletter - 2015, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 8, No. 1

The department of Geosciences 50th anniversary issue.


Sequence Stratigraphic Framework Of Carbonate Diagenesis Within Neogene Glaciomarine Sandstones Of The Victoria Land Basin, Antarctica: Insights Into Reservoir Quality In Polar Settings, Daniel P. Dunham Dec 2015

Sequence Stratigraphic Framework Of Carbonate Diagenesis Within Neogene Glaciomarine Sandstones Of The Victoria Land Basin, Antarctica: Insights Into Reservoir Quality In Polar Settings, Daniel P. Dunham

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

The controls on reservoir quality of most clastic sedimentary deposits are well-documented and understood. However, comparatively little is known about the reservoir potential of glaciogenic and glaciomarine deposits. This study investigates the Neogene strata of the AND-2A core recovered by the ANDRILL-Southern McMurdo Sound Project in the Victoria Land Basin, Antarctica, as an analog for assessing controls on reservoir quality in glaciomarine deposits. A petrographic analysis was conducted on 60 sandstone samples from various depths throughout the core, and carbonate diagenetic phases and morphologies were documented. Four sequences were examined in detail. Point counting on all samples was done to …


Modeling Of Gas Production From Shale Reservoirs Considering Multiple Transport Mechanisms, Chaohua Guo, Mingzhen Wei, Hong Liu Dec 2015

Modeling Of Gas Production From Shale Reservoirs Considering Multiple Transport Mechanisms, Chaohua Guo, Mingzhen Wei, Hong Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Gas transport in unconventional shale strata is a multi-mechanism-coupling process that is different from the process observed in conventional reservoirs. In micro fractures which are inborn or induced by hydraulic stimulation, viscous flow dominates. And gas surface diffusion and gas desorption should be further considered in organic nano pores. Also, the Klinkenberg effect should be considered when dealing with the gas transport problem. In addition, following two factors can play significant roles under certain circumstances but have not received enough attention in previous models. During pressure depletion, gas viscosity will change with Knudsen number; and pore radius will increase when …


Infrasound From Volcanic Rockfalls, Jeffrey B. Johnson, Timothy J. Ronan Dec 2015

Infrasound From Volcanic Rockfalls, Jeffrey B. Johnson, Timothy J. Ronan

CGISS Publications and Presentations

Proximal infrasound arrays can robustly track rapidly moving gravity-driven mass wasting, which occurs commonly at erupting volcanoes. This study reports on detection, localization, and quantification of frequent small rockfalls and infrequent pyroclastic density currents descending the southeast flanks of Santiaguito’s active Caliente Dome in January of 2014. Such activities are identified as moving sources, which descend several hundred meters at bulk flow speeds of up to ~10 m/s, which is considerably slower than the descent velocity of individual blocks. Infrasound rockfall signal character is readily distinguishable from explosion infrasound, which is manifested by a relatively fixed location source with lower …


Umphlett Qci 2015, Natalie A. Umphlett Dec 2015

Umphlett Qci 2015, Natalie A. Umphlett

HPRCC Personnel Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Late Hard Freeze

Late Freezes Extended Growing Season

Warm Fall Delays Bird Migrations

Monitoring Water Resources Across the Basin

3-Month Precipitation and Temperature Outlooks


Validation Of The Global Distribution Of Co2 Volume Mixing Ratio In The Mesosphere And Lower Thermosphere From Saber, L. Rezac, Y. Jian, J. Yue, J. M. Russell Iii, A. Kutepov, R. Garcia, K. Walker, P. Bernath Dec 2015

Validation Of The Global Distribution Of Co2 Volume Mixing Ratio In The Mesosphere And Lower Thermosphere From Saber, L. Rezac, Y. Jian, J. Yue, J. M. Russell Iii, A. Kutepov, R. Garcia, K. Walker, P. Bernath

Chemistry & Biochemistry Faculty Publications

The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on board the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite has been measuring the limb radiance in 10 broadband infrared channels over the altitude range from ~ 400 km to the Earth's surface since 2002. The kinetic temperatures and CO2 volume mixing ratios (VMRs) in the mesosphere and lower thermosphere have been simultaneously retrieved using SABER limb radiances at 15 and 4.3 μm under nonlocal thermodynamic equilibrium (non-LTE) conditions. This paper presents results of a validation study of the SABER CO2 VMRs obtained with a two-channel, self-consistent …


Numerical Analysis Of Groundwater Flow And Potential In Parts Of A Crystalline Aquifer System In Northern Ghana, Sandow Mark Yidana, Clement Alo, M. O. Addai, O. F. Fynn, S. K. Essel Dec 2015

Numerical Analysis Of Groundwater Flow And Potential In Parts Of A Crystalline Aquifer System In Northern Ghana, Sandow Mark Yidana, Clement Alo, M. O. Addai, O. F. Fynn, S. K. Essel

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The groundwater flow system in a crystalline aquifer system in parts of Northern Ghana was simulated and calibrated under steady-state conditions. The objective was to estimate the regional distribution of a key aquifer hydraulic parameter (the hydraulic conductivity) and recharge and also to predict possible effects of different abstraction and groundwater recharge scenarios on the sustainability of groundwater resources in the area. The study finds that the hydraulic conductivity field is quite homogeneous and has values ranging between 1.70 and 2.24 m/day. There is an apparent dominance of regional groundwater flow systems compared to local flow systems. This is probably …


Hierarchical Segmentation Of The Malawi Rift: The Influence Of Inherited Lithospheric Heterogeneity And Kinematics In The Evolution Of Continental Rifts, Daniel A. Lao-Davila, Haifa S. Al-Salmi, Mohamed G. Abdel Salam, Estella A. Atekwana Dec 2015

Hierarchical Segmentation Of The Malawi Rift: The Influence Of Inherited Lithospheric Heterogeneity And Kinematics In The Evolution Of Continental Rifts, Daniel A. Lao-Davila, Haifa S. Al-Salmi, Mohamed G. Abdel Salam, Estella A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We used detailed analysis of Shuttle Radar Topography Mission-digital elevation model and observations from aeromagnetic data to examine the influence of inherited lithospheric heterogeneity and kinematics in the segmentation of largely amagmatic continental rifts. We focused on the Cenozoic Malawi Rift, which represents the southern extension of the Western Branch of the East African Rift System. This north trending rift traverses Precambrian and Paleozoic-Mesozoic structures of different orientations. We found that the rift can be hierarchically divided into first-order and second-order segments. In the first-order segmentation, we divided the rift into Northern, Central, and Southern sections. In its Northern Section, …