Earth Sciences Commons^™

The Effects Of Altitude And Micro-Spatial Habitats On The Physiognomic Characteristics Of Syzygium Guineense In Mazumbai Forest Reserve, Erin Brynn Zalmanek

Independent Study Project (ISP) Collection

In order to examine the affects that altitude and micro-spatial habitat have on the physiognomy of Syzygium Guineense; buttress sphere size, number of buttresses, relative size of the buttresses, DBH, and height were measured in three different altitudinal bands (1400 - 1500 m, 1500 - 1600 m, and 1600 - 1700 m) and three different habits portraying concave, convex, and intermediate landscapes. Micro-spatial habits showed to have weak to no effect on all measured physiognomic variables giving insignificant p-values according to ANOVA. However, correlation tests against leaf litter depth and slope showed to have some relation to the size and …

Evaluation Of Collapse Indicators For Seismically Vulnerable Reinforced Concrete Buildings, Nicholas R. Skok

Open Access Theses

Older reinforced concrete buildings can be prone to column shear and compression failures during earthquakes because of inadequate transverse reinforcement. Cities in seismic areas still have large inventories of older and potentially deficient buildings. To analyze every building and estimate its vulnerability in detail is costly. A simple method to rank quickly older buildings according to their seismic vulnerability is needed to help engineers prioritize the use of resources for rehabilitating the most vulnerable buildings.

Four indicators of building damage or collapse were evaluated using numerical analysis and prior data from building surveys: column index (Hassan & Sozen, 1997), R …

General Brochure, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Brochure about the Energy & Environmental Research Center, including its philosophy, partnerships, program areas, history, and Centers of Excellence. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Gps Constraints On The Mw = 7.5 Ometepec Earthquake Sequence, Southern Mexico: Coseismic And Post-Seismic Deformation, Shannon E. Graham, Charles Demets, Enrique Cabral-Cano, Vladimir Kostoglodov, Andrea Walpersdorf, Nathalie Cotte, Michael Brudzinski, Robert Mccaffrey, Luis Salazar-Tlaczani

Geology Faculty Publications and Presentations

We use continuous GPS measurements from 31 stations in southernMexico to model coseismic slip and post-seismic deformation from the 2012 March 20 Mw = 7.5 Ometepec earthquake, the first large thrust earthquake to occur below central Mexico during the modern GPS era. Coseismic offsets ranging from ∼280 mm near the epicentre to 5 mm or less at sites far from the epicentre are fit best by a rupture focused between ∼15 and 35 km depth, consistent with an independent seismological estimate. The corresponding geodetic moment of 1.4 × 10²⁰ N·m is within 10 per cent of two independent seismic …

Hydro-Climate Temporal Variations And Their Influences On Net Primary Production In A Eurasian Steppe Watershed, Xiaomin Yang

Civil & Environmental Engineering Theses & Dissertations

Climate, which is the most important factor that influences Net Primary Productivity, has been detected changing all over the world. The confounding effects of step change invalidate the stationarity assumption of commonly used trend analysis methods such as the Mann-Kendall test technique, so previous studies have failed to explain inconsistencies between detected trends and observed large anomalies. In this research, by formulating a trend analysis approach that considers nonstationary due to step changes, trends and extreme occurrences of precipitation, temperature, and runoff in annual, seasonal, and monthly scales were analyzed in a mid-latitude Eurasian steppe watershed in northeast China, and …

Paleoecology Of Late Cretaceous Methane Cold-Seeps Of The Pierre Shale, South Dakota, Kimberly Cynthia Handle

Dissertations, Theses, and Capstone Projects

Most investigations of ancient methane seeps focus on either the geologic or paleontological aspects of these extreme environments. In contrast, this thesis encompasses both disciplines to evaluate the paleoecology of these systems with greater detail than previously published either within the Western Interior Basin or elsewhere. This thesis addresses the following questions: 1) Are the changes in mineralogy of a seep discernable and predictable as a seep shifts from a clay-based environment to a carbonate-based environment? 2) What are the foundation organism(s) of Late Cretaceous methane cold-seeps? 3) Is there a correlation to the mineralogic changes and shifts in community …

First Record Of The Tropical House Gecko Hemidactylus Mabouia (Moreau De Jonnès, 1818) In Texas, Alejandro Fierro-Cabo, August Rentfro

School of Earth, Environmental, & Marine Sciences Faculty Publications

Invasions of the tropical house gecko Hemidactylus mabouia (Moreau de Jonnes, 1818) in the tropical Americas are well documented. While this gecko has been reported as well established and expanding its range in Florida, here we document the first record in the United States outside of this state. We detected a small reproducing population in Cameron County, Brownsville, Texas. We expect a rapid colonization of buildings by this species in southern Texas. We consider that this potential invasion poses novel obstacles to the continued presence of the earlier invasive Mediterranean gecko Hemidactylus turcicus (Linnaeus, 1758) across Texas

Crustal Accretion And Mantle Geodynamics At Microplates: Constraints From Gravity Analysis And Numerical Modeling, Katherine Ames

OES Theses and Dissertations

This study investigates crustal accretion and mantle geodynamics at microplates using mantle Bouguer anomaly (MBA) gravity calculations and exploratory numerical models. The Easter and Juan Fernandez microplates are located in the eastern Pacific Ocean along the Pacific, Nazca, and Antarctic plate boundaries. Both microplates formed 3-5 Ma and they are currently rotating clockwise at 15° myr^-1 and 9° myr^-1,respectively [ e.g., Searle et al., 1993]. The study area also encompasses the Easter /Salas y Gomez mantle plume located near the Easter microplate. Both microplates show a difference in average MBA between their west and east ridges, with …

Loess As A Quaternary Paleoenvironmental Indicator, Daniel R. Muhs, M. A. Prins, B. Machalett

United States Geological Survey: Staff Publications

Loess (aeolian silt) is widespread in Eurasia and the Americas. Paleowind direction and wind strength can be reconstructed from spatial and temporal trends of loess thickness and particle size. Fossil land snails in loess can reveal much about past climate and vegetation.

Loess is aeolian sediment that is dominated by silt-sized particles. Unlike either coarser dune sand or finer-grained, long-rangetransported dust, loess is relatively poorly sorted, reflecting a combination of transport processes, including saltation, low suspension, and high suspension. Loess can be readily identified in the field; deposits range in thickness from a few centimeters to many tens of meters, …

The Interaction Between Arsenic And Struvite During Coprecipitation And Adsorption Processes, Ning Ma

Dissertations, Theses, and Capstone Projects

The formation of struvite, MgNH4PO4*6H2O (MAP), from wastes is one of the methods that can be used to recover P from wastes efficiently. However, since there are usually toxic components in the wastes, like arsenic (As), the possibility of having toxic contaminants in MAP is a big concern. So, the interaction between As and MAP during coprecipitation (CPT) and adsorption (ADS) processes were studied at pH 8-11. MAP precipitated without As at pH 8-11 was also characterized.

During CPT process, the MAP was precipitated from a MgCl2-(NH4)2HPO4-NaCl-H2O system spiked with As at an initial pH (pHi) of 8-11. The batch …

Carbon And Nitrogen Dynamics From Slow Pools Of Soil Organic Matter In A Temperate Forest: Pyrogenic Organic Matter And And Root Litter, Fernanda Dos Santos

Dissertations, Theses, and Capstone Projects

Soil organic matter (SOM) is the dominant reservoir of organic carbon (OC) in terrestrial ecosystems, storing approximately three times the size of the C pool in the atmosphere. In temperate forests, a major fraction of the SOM consists of slowly decaying soil organic C (SOC) pools. While slowly cycling C pools constitute a large reservoir of stable C in soils, the dominant environmental factors controlling this C pool remain unresolved. This research investigates two significant, but poorly characterized slowly decaying C pools: fine root litter (< 2mm) and thermally altered plant biomass (pyrogenic organic matter, PyOM). Specifically, I used compound-specific stable isotope analysis (¹³C and ¹⁵N) as my main methodological approach to examine the (1) …

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …

U.S. Drought Monitor, September 30, 2014, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for September 30, 2014 (9/30/14) plus: United States crop areas experiencing drought (map), an approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during the past 52 weeks (line graph) for corn, soybeans, hay, cattle, and winter wheat.

Carbon Losses From Pyrolysed And Original Wood In A Forest Soil Under Natural And Increased N Deposition, B. Maestrini, S. Abiven, N. Singh, J. Bird, M. W. I. Schmidt

Publications and Research

Pyrogenic organic matter (PyOM) plays an important role as a stable carbon (C) sink in the soils of terrestrial ecosystems. However, uncertainties remain about in situ turnover rates of fire-derived PyOM in soil, the main processes leading to PyOM-C and nitrogen (N) losses from the soil, and the role of N availability on PyOM cycling in soils. We measured PyOM and native soil organic carbon losses from the soil as carbon dioxide and dissolved organic carbon (DOC) using additions of highly 13C-labelled PyOM (2.03 atom %) and its precursor pinewood during 1 year in a temperate forest soil. The field …

Air Mass Frequency During Precipitation Events In The Northern Plains Of The United States, Anthony Baum, Richard De Pasquale, Melissa L. Godek

The Compass: Earth Science Journal of Sigma Gamma Epsilon

Since 1980, numerous billion-dollar disasters have affected the Northern Plains of the United States, including nine droughts and four floods. The atmospheric environment present during precipitation events can largely be described by the presiding air mass conditions since air masses characterize a multitude of meteorological variables at one time over a large region. The goal of this research is to add knowledge to current understandings of the factors responsible for precipitation in the Northern Plains through an assessment of synoptic air mass conditions. The Spatial Synoptic Classification is used to categorize 30 years of daily surface air mass types across …

A New Ankylosaurid Dinosaur From The Upper Cretaceous (Kirtlandian) Of New Mexico With Implications For Ankylosaurid Diversity In The Upper Cretaceous Of Western North America, Victoria M. Arbour, Michael E. Burns, Robert M. Sullivan, Spencer G. Lucas, Amanda K. Cantrell, Joshua Fry, Thomas L. Suazo

Geosciences Faculty Publications

A new ankylosaurid (Ankylosauria: Dinosauria), Ziapelta sanjuanensis, gen. et sp. nov., is based on a complete skull, an incomplete first cervical half ring, a possible fragment of the second cervical half ring, and additional fragmentary osteoderms. The holotype specimen is from the Upper Cretaceous (Upper Campanian, Kirtlandian Land-Vertebrate Age) Kirtland Formation (De-na-zin Member) at Hunter Wash, San Juan Basin, in northwestern New Mexico, USA. Diagnostic characters of Ziapelta include: a large, prominent triangular median nasal caputegulum; a mixture of flat and bulbous frontonasal caputegulae; ventrolaterally oriented squamosal horns with a sharp, prominent dorsal keel; and the ventral surface of basicranium …

U.S. Drought Monitor, September 23, 2014, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for September 23, 2014 (9/23/14) plus: United States crop areas experiencing drought (map), an approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during the past 52 weeks (line graph) for corn, soybeans, hay, cattle, and winter wheat.

Noble Gases Identify The Mechanisms Of Fugitive Gas Contamination In Drinking-Water Wells Overlying The Marcellus And Barnett Shales, Thomas H. Darrah, Avner Vengosh, Robert B. Jackson, Nathaniel R. R. Warner, Robert J. Poreda

Dartmouth Scholarship

Horizontal drilling and hydraulic fracturing have enhanced energy production but raised concerns about drinking-water contamination and other environmental impacts. Identifying the sources and mechanisms of contamination can help improve the environmental and economic sustainability of shale-gas extraction. We analyzed 113 and 20 samples from drinking-water wells overlying the Marcellus and Barnett Shales, respectively, examining hydrocarbon abundance and isotopic compositions (e.g., C2H6/CH4, δ13C-CH4) and providing, to our knowledge, the first comprehensive analyses of noble gases and their isotopes (e.g., 4He, 20Ne, 36Ar) in groundwater near shale-gas wells. We addressed two questions. (i) Are elevated levels of hydrocarbon gases in …

Application Of High-Resolution Spectral Absorbance Measurements To Determine Dissolved Organic Carbon Concentration In Remote Areas, Armine Avagyan, Benjamin R. K. Runkle, Lars Kutzbach

Biological and Agricultural Engineering Faculty Publications and Presentations

Accurate quantification of dissolved organic carbon (DOC) in surface and soil pore waters is crucial for understanding changes in water resources under the influence of climate and land use changes. Sampling and laboratory analysis of DOC content at a sufficient temporal frequency are especially difficult to achieve for natural DOC sources like the extensive boreal and arctic mire landscapes due to their remoteness. Therefore, the goals of this paper are (1) to investigate the performance of a portable, high-resolution ultraviolet–visible light spectroscopic method for determining the DOC content of surface and soil pore water samples from a boreal mire complex …

U.S. Drought Monitor, September 16, 2014, Michael J. Brewer

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for September 16, 2014 (9/16/14) 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.

Calculating The Velocity Of A Fast-Moving Snow Avalanche Using An Infrasound Array, Scott Havens, Hans-Peter Marshall, Jeffrey B. Johnson, Bill Nicholson

Geosciences Faculty Publications and Presentations

On 19 January 2012, a large D3 avalanche (approximately 10³ t) was recorded with an infrasound array ideally situated for observing the avalanche velocity. The avalanche crossed Highway 21 in Central Idaho during the largest avalanche cycle in the 15 years of recorded history and deposited approximately 8 m of snow on the roadway. Possible source locations along the avalanche path were estimated at 0.5 s intervals and were used to calculate the avalanche velocity during the 64 s event. Approximately 10 s prior to the main avalanche signal, a small infrasound signal originated from the direction of the …

Analysis, Toxicity, Occurrence And Biodegradation Of Nonylphenol Isomers: A Review, Zhijiang Lu, Jay Gan

Environmental Science and Geology Faculty Research Publications

Over the last two decades, nonylphenols (NPs) have become to be known as a priority hazardous substance due primarily to its estrogenicity and ubiquitous occurrence in the environment. Nonylphenols are commonly treated as a single compound in the evaluation of their environmental occurrence, fate and transport, treatment or toxicity. However, technical nonylphenols (tNPs) are in fact a mixture of more than 100 isomers and congeners. Recent studies showed that some of these isomers behaved significantly differently in occurrence, estrogenicity and biodegradability. The most estrogenic isomer was about 2 to 4 times more active than tNP. Moreover, the half lives of …

U.S. Drought Monitor, September 9, 2014, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for September 9, 2014 (9/9/14) 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.

Age Of Barrier Canyon-Style Rock Art Constrained By Cross-Cutting Relations And Luminescence Dating Techniques, Joel L. Pederson, Harriet Cornachione, Steven R. Simms, Reza Sohbati, Tammy M. Rittenour, Andrew S. Murray, Gary Cox

Geosciences Faculty Publications

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial …

U.S. Drought Monitor, September 2, 2014, David Simeral

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for September 2, 2014 (9/2/14) 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.

Umphlett Qci Sept 2014, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

􏰞􏰥􏰬􏰨􏰤􏰵􏰶􏰫Streamflow

Long-term Impacts of Drought

Cool, Wet Summer Benefits

Heavy Precipitation Impacts the Missouri River and its Tributaries

3-Month Precipitation and Temperature Outlooks

Soil Moisture Conditions

Postglacial Early Permian (Late Sakmarian– Early Artinskian) Shallow-Marine Carbonate Deposition Along A 2000 Km Transect From Timor To West Australia, Vladimir I. Davydov

Geosciences Faculty Publications and Presentations

Late Sakmarian to early Artinskian (Early Permian) carbonate deposition was widespread in the marine intracratonic rift basins that extended into the interior of Eastern Gondwana from Timor in the north to the northern Perth Basin in the south. These basins spanned about 20° of paleolatitude (approximately 35°S to 55°S). This study describes the type section of the Maubisse Limestone in Timor-Leste, and compares this unit with carbonate sections in the Canning Basin (Nura Nura Member of the Poole Sandstone), the Southern Carnarvon Basin (Callytharra Formation) and the northern Perth Basin (Fossil Cliff Member of the Holmwood Shale). The carbonate units …

Understanding And Assessing Climate Change: Implications For Nebraska, Deborah J. Bathke, Robert J. Oglesby, Clinton Rowe, Donald A. Wilhite

Department of Earth and Atmospheric Sciences: Faculty Publications

This report was commissioned by the UNL Institute of Agriculture and Natural Resources (IANR) with the objective of evaluating and summarizing the existing scientific literature related to our changing climate. Scientists from the IANR’s School of Natural Resources and the Department of Earth and Atmospheric Sciences in the College of Arts and Sciences have been the principal contributors to the report under the able leadership of long-time, internationally leading applied climate scientist Professor Don Wilhite. Their efforts have resulted in a timely and seminal reference for state and local policy-makers, government agency leaders, private industry, and indeed all citizens of …

Field Trip Guidebook For The Nebraska Well Drillers Association, Duane A. Eversoll, Matt Joeckel, Lee Orton

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Economic Geology Of The San Bernardino Mountains, California, Nicolette Deannah Grill

Electronic Theses, Projects, and Dissertations

The San Bernardino Mountains are well known for their rich mining history, especially, gold in the mid-1800s and the current mining of one of the world’s largest deposits of high purity limestone. The purpose of this study was to compile new, current, and historical data of the major economic resources that are present and mining that has gone on in the San Bernardino Mountains. It is estimated that historical mining of the Holcomb Valley recovered $457,660,000 of gold or about 350,000 troy ounces based on samples collected for this study and 2013 gold price. The current major geologic resource is …