Earth Sciences Commons^™

Age And Pattern Of The Southern High-Latitude Continental End-Permian Extinction Constrained By Multiproxy Analysis, Christopher R. Fielding, Tracy D. Frank, Stephen Mcloughlin, Vivi Vajda, Chris Mays, Allen P. Tevyaw, Arne Winguth, Cornelia Winguth, Robert S. Nicoll, Malcom Bocking, James L. Crowley

Department of Earth and Atmospheric Sciences: Faculty Publications

Past studies of the end-Permian extinction (EPE), the largest biotic crisis of the Phanerozoic, have not resolved the timing of events in southern high-latitudes. Here we use palynology coupled with high-precision CA-ID-TIMS dating of euhedral zircons from continental sequences of the Sydney Basin, Australia, to show that the collapse of the austral Permian Glossopteris flora occurred prior to 252.3 Ma (~370 kyrs before the main marine extinction). Weathering proxies indicate that floristic changes occurred during a brief climate perturbation in a regional alluvial landscape that otherwise experienced insubstantial change in fluvial style, insignificant reorganization of the depositional surface, and no …

Multi-Proxy Constraints On The Significance Of Covariant Δ13c Values In Carbonate And Organic Carbon During The Early Mississippian, Amanda M. Oehlert, Peter K. Swart, Gregor P. Eberli, Samantha Evans, Tracy D. Frank

Department of Earth and Atmospheric Sciences: Faculty Publications

This study investigates the covariation between carbonate and organic δ¹³C values in a proximal to distal transect of four outcrops in the Madison Limestone in the Western United States Rockies, combined with δ³⁴S values of carbonate associated sulphate, the concentration of acid-insoluble material and measurements of total organic carbon. These new geochemical datasets not only allow for an evaluation of carbon isotope covariance during one of the largest perturbations to the global carbon cycle over the past 550 Myr, but also constrain the cause of the excursion in carbonate δ¹³C values. The results support …

Hexagonal Fracture Patterns On Navajo Sandstone Crossbeds At Yellow Knolls, Washington County, David Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

At this geosite, the main features of interest—remarkably uniform and beautiful fracture patterns dominantly composed of linked hexagons (fi gures 1 and 2)—are present on outcrops of the Jurassic Navajo Sandstone. Th e Navajo was deposited by large, southward- migrating desert dunes about 200 million years ago, but the fractures that defi ne the hexagons here are just a surfi cial veneer less than 20 inches (half a meter) deep. Th e fractures are a weathering phenomenon that developed under climate conditions similar to today’s. Steep thermal gradients develop in the sandstone because it is exposed to solar radiation and …

The Origin Of Shinarump Wonderstone, Hildale, Washington County, Richard Kettler, David Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

Southern Utah’s “wonderstone” is Shinarump sandstone, variably cemented and stained with iron oxide, forming intricate patterns reminiscent of landscapes. It is cut and sold as absorbent drink coasters and decorative objects, and is seen in rock shops across the country. The wonderstone pattern comprises thick bands of iron oxide mineralization that fills pore space (referred to as iron oxide cement or IOC) and more delicate bands of iron oxide mineralization that coats sand grains but does not fill pore space (referred to as iron oxide stain or IOS) (figure 1).

The wonderstone pattern is of interest to geologists because it …

Developing A Department Of Transportation Winter Severity Index, Curtis L. Walker, Dylan Steinkruger, Pouya Gholizadeh, Sogand Hasanzedah, Mark Anderson, Behzad Esmaeili

Department of Earth and Atmospheric Sciences: Faculty Publications

Adverse weather conditions are responsible for millions of vehicular crashes, thousands of deaths, and billions of dollars per year in economic and congestion costs. Many transportation agencies utilize a performance or mobility metric to assess how well they maintain road access; however, there is only limited consideration of meteorological impacts to the success of their operations. This research develops the Nebraska winter severity index (NEWINS), which is a daily event-driven index derived for the Nebraska Department of Transportation (NDOT). The NEWINS includes a categorical storm classification framework to capture atmospheric conditions and possible road impacts across diverse spatial regions of …

Seismicity In Nebraska And Adjacent States: The Historical Perspective And Current Trends, Irina Filina, Kris Guthrie, Mindi Searls, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

A sudden spike in earthquake events has been observed in central Nebraska. Since April 2018, 26 earthquakes with equivalent moment magnitudes from 2.7 to 4.1 occurred, clustered tightly in Custer County. A similar cluster of 24 earthquakes with equivalent moment magnitudes from 2.6 to 3.7 occurred in Jewell County in northern Kansas in 2017. We have compiled an earthquake database for Nebraska and parts of adjacent states from different sources to determine whether these recent earthquake spikes are consistent with historic seismicity. We identified two historic earthquake clusters occurring in our study area. The first contained 32 events and was …

Using Cumulative Potential Recharge For Selection Of Gcm Projections To Force Regional Groundwater Models: A Nebraska Sand Hills Example, Nathan R. Rossman, Vitaly A. Zlotnik, Clinton Rowe

Department of Earth and Atmospheric Sciences: Faculty Publications

Groundwater recharge (GR) controls vegetation, geomorphology, groundwater, wetlands and surface flow, and ultimately, the ecology and economics of semi-arid regions. Therefore, it is critical to assess hydroclimate model scenarios and the uncertainty in future GR to force regional groundwater models. We use basic statistics of downscaled Global Circulation Model (GCM)-projected cumulative potential GR (GR_p) for selecting representative projections. Cumulative GR_p is the net recharge (difference between precipitation (P) and evapotranspiration (ET) rates) over the projection period. The approach is illustrated with an example in the Nebraska Sand Hills (NSH), the largest dune …

Placing The Common Era In A Holocene Context: Millennial To Centennial Patterns And Trends In The Hydroclimate Of North America Over The Past 2000 Years, Bryan N. Shuman, Cody Routson, Nicholas Mckay, Sherilyn C. Fritz, Darrell Kaufman, Matthew E. Kirby, Connor Nolan, Gregory T. Pederson, Jeannine-Marie St-Jacques

Department of Earth and Atmospheric Sciences: Faculty Publications

A synthesis of 93 hydrologic records from across North and Central America, and adjacent tropical and Arctic islands, reveals centennial to millennial trends in the regional hydroclimates of the Common Era (CE; past 2000 years). The hydrological records derive from materials stored in lakes, bogs, caves, and ice from extant glaciers, which have the continuity through time to preserve low-frequency ( > 100 year) climate signals that may extend deeper into the Holocene. The most common pattern, represented in 46 (49 %) of the records, indicates that the centuries before 1000 CE were drier than the centuries since that time. Principal …

Impact Of Grassland Conversion To Forest On Groundwater Recharge In The Nebraska Sand Hills, Zablon A. Adane, Paolo Nasta, Vitaly A. Zlotnik, David A. Wedin

Department of Earth and Atmospheric Sciences: Faculty Publications

Study region: Nebraska National Forest in the High Plains Aquifer, Nebraska Sand Hills, U.S.A. Study focus: This research aimed to investigate the effects of grassland conversions to forest on recharge rates in a century-old experimental forest. The DiffeRential Evolution Adaptive Metropolis (DREAM_ZS) global optimization algorithm was used to calibrate the effective soil hydraulic parameters from observed soil moisture contents for 220 cm deep uniform soil profiles. The historical recharge rates were then estimated by applying the numerical model HYDRUS 1-D for simulation of two plots representing grasslands and dense pine forest conditions. New hydrological insights: The results indicate …

Land-Cover Change And The ‘‘Dust Bowl’’ Drought In The U.S. Great Plains, Qi Hu, Jose Abraham Torres-Alavez, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

The North American Dust Bowl drought during the 1930s had devastating environmental and societal impacts. Comprehending the causes of the drought has been an ongoing effort in order to better predict similar droughts and mitigate their impacts. Among the potential causes of the drought are sea surface temperature (SST) anomalies in the tropical Pacific Ocean and strengthened local sinking motion as a feedback to degradation of the land surface condition leading up to and during the drought. Limitations on these causes are the lack of a strong tropical SST anomaly during the drought and lack of local anomaly in moisture …

The Impact Of Sensor Response And Airspeed On The Representation Of The Convective Boundary Layer And Airmass Boundaries By Small Unmanned Aircraft Systems, Adam L. Houston, Jason M. Keeler

Department of Earth and Atmospheric Sciences: Faculty Publications

The objective of the research presented is to assess the impact of sensor response and aircraft airspeed on the accuracy of in situ observations collected by small unmanned aircraft systems profiling the convective boundary layer or transecting airmass boundaries. Estimates are made using simulated aircraft flown within large-eddy simulations. Both instantaneous errors (differences between observed temperature, which include the effects of sensor response and airspeed, and actual temperature) and errors in representation (differences between serial observations and representative snapshots of the atmospheric state) are considered. Synthetic data are retrieved assuming a well-aspirated first-order sensor mounted on rotary-wing aircraft operated as …

Lake Regionalization And Diatom Metacommunity Structuring In Tropical South America, Xavier Benito, Sherilyn C. Fritz, Miriam Steinitz-Kannan, Maria I. Velez, Michael M. Mcglue

Department of Earth and Atmospheric Sciences: Faculty Publications

Lakes and their topological distribution across Earth’s surface impose ecological and evolutionary constraints on aquatic metacommunities. In this study, we group similar lake ecosystems as metacommunity units influencing diatom community structure. We assembled a database of 195 lakes from the tropical Andes and adjacent lowlands (8°N–30°S and 58–79°W) with associated environmental predictors to examine diatom metacommunity patterns at two different levels: taxon and functional (deconstructed species matrix by ecological guilds). We also derived spatial variables that inherently assessed the relative role of dispersal. Using complementary multivariate statistical techniques (principal component analysis, cluster analysis, nonmetric multidimensional scaling, Procrustes, variance partitioning), we …

Sheeting Joints And Polygonal Patterns In The Navajo Sandstone, Southern Utah: Controlled By Rock Fabric, Tectonic Joints, Buckling, And Gullying, David B. Loope, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

Sheeting joints are ubiquitous in outcrops of the Navajo Sandstone on the west-central Colorado Plateau, USA. As in granitic terrains, these are opening- mode fractures and form parallel to land surfaces. In our study areas in south-central Utah, liquefaction during Jurassic seismic events destroyed stratification in large volumes of eolian sediment, and first-order sheeting joints are now preferentially forming in these structureless (isotropic) sandstones. Vertical cross-joints abut the land-surface-parallel sheeting joints, segmenting broad (tens of meters) rock sheets into equant, polygonal slabs ~5 m wide and 0.25 m thick. On steeper slopes, exposed polygonal slabs have domed surfaces; eroded slabs …

Cosmic-Ray Neutron Probes On The High Plains Of Nebraska: Applications To Large Scale Agriculture, Trenton E. Franz, Darin Desilets, Ammar Wahbi

Department of Earth and Atmospheric Sciences: Faculty Publications

Cosmic-rays have some surprising applications in precision agriculture. The cosmic-ray neutron probe (CRNP), when implemented as a roving instrument, can be used to create spatial maps of soil moisture, and from these maps soil hydraulic properties can be inferred. In this work, we combine data from a mobile CRNP with laboratory samples to make spatial predictions of soil hydraulic properties for select field sites around the state of Nebraska. These maps, which focus on wilting point and field capacity, can, in turn, be used to determine the optimal timing and application rates for irrigation farmers, many of whom have the …

Sheeting Joints And Polygonal Patterns In The Navajo Sandstone, Southern Utah: Controlled By Rock Fabric, Tectonic Joints, Buckling, And Gullying, David Loope, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

Sheeting joints are ubiquitous in outcrops of the Navajo Sandstone on the west-central Colorado Plateau, USA. As in granitic terrains, these are opening- mode fractures and form parallel to land surfaces. In our study areas in south-central Utah, liquefaction during Jurassic seismic events destroyed stratification in large volumes of eolian sediment, and first-order sheeting joints are now preferentially forming in these structureless (isotropic) sandstones. Vertical cross-joints abut the land-surface-parallel sheeting joints, segmenting broad (tens of meters) rock sheets into equant, polygonal slabs ~5 m wide and 0.25 m thick. On steeper slopes, exposed polygonal slabs have domed surfaces; eroded slabs …

Recent Ecological Change In Ancient Lakes, Stephanie E. Hampton, Suzanne Mcgowan, Ted Ozersky, Salvatore G. P. Virdis, Tuong Thuy Vu, Trisha L. Spanbauer, Benjamin M. Kraemer, George Swann, Anson W. Mackay, Stephen M. Powers, Michael F. Meyer, Stephanie G. Labou, Catherine M. O'Reilly, Morgan Dicarlo, Aaron W. E. Galloway, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

Ancient lakes are among the best archivists of past environmental change, having experienced more than one full glacial cycle, a wide range of climatic conditions, tectonic events, and long association with human settlements. These lakes not only record long histories of environmental variation and human activity in their sediments, but also harbor very high levels of biodiversity and endemism. Yet, ancient lakes are faced with a familiar suite of anthropogenic threats, which may degrade the unusual properties that make them especially valuable to science and society. In all ancient lakes for which data exist, significant warming of surface waters has …

Ensemble Sensitivity Analysis For Targeted Observations Of Supercell Thunderstorms, George L. Limpert, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

Ensemble sensitivity analysis (ESA) has been demonstrated for observation targeting of synoptic-scale and mesoscale phenomena, but could have similar applications for storm-scale observations with mobile platforms. This paper demonstrates storm-scale ESA using an idealized supercell simulated with a 101-member CM1 ensemble. Correlation coefficients are used as a measure of sensitivity and are derived from single-variable and multivariable linear regressions of pressure, temperature, humidity, and wind with forecast response variables intended as proxies for the strength of supercells. This approach is suitable for targeting observing platforms that simultaneously measure multiple base-state variables. Although the individual correlations are found to be noisy …

An Observational And Modeling Study Of Mesoscale Air Masses With High Theta-E, Wolfgang Hanft, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

Typically, the cool side of an airmass boundary is stable to vertical motions due to its associated negative buoyancy. However, under certain conditions, the air on the cool side of the boundary can undergo a transition wherein it assumes an equivalent potential temperature and surface-based convective available potential energy that are higher than those of the air mass on the warm side of the boundary. The resultant air mass is herein referred to as a mesoscale air mass with high theta-e (MAHTE). Results are presented from an observational and mesoscale modeling study designed to examine MAHTE characteristics and the processes …

Evaluating Soil Moisture–Precipitation Interactions Using Remote Sensing: A Sensitivity Analysis, Trent W. Ford, Steven M. Quiring, Balbhadra Thakur, Rohit Jogineedi, Adam Houston, Shanshui Yuan, Ajay Kalra, Noah Lock

Department of Earth and Atmospheric Sciences: Faculty Publications

The complex interactions between soil moisture and precipitation are difficult to observe, and consequently there is a lack of consensus as to the sign, strength, and location of these interactions. Inconsistency between soil moisture–precipitation interaction studies can be attributed to a multitude of factors, including the difficulty of demonstrating causal relationships, dataset differences, and precipitation autocorrelation. The purpose of this study is to explore these potential confounding factors and determine which are most important for consideration when assessing statistical coupling between soil moisture and precipitation. Soil moisture is assessed via three remote sensing datasets: theAdvancedMicrowave Scanning Radiometer for EarthObserving System, …

Joint And Lineament Patterns Across The Midcontinent Indicate Repeated Reactivation Of Basement-Involved Faults, Caroline M. Burberry, Jerlyn L. Swiatlowski, Mindi L. Searls, Irina Filina

Department of Earth and Atmospheric Sciences: Faculty Publications

Joint networks hosted in successively younger rocks, developing as a result of forced (trishear) folding of a rock mass above a deep-seated fault, can be used to infer the reactivation history of that deep-seated fault. This study aims to use joint networks in Pennsylvanian, Permian and Cretaceous rocks to document evidence of reactivation on basement faults during the Paleozoic and Mesozoic of Nebraska and Kansas. The most prominent basement features in southeast Nebraska and northeast Kansas are oriented NE-SW, likely related to the Midcontinent Rift System and Nemaha Uplift, and oriented NW-SE, likely related to fabrics from the Central Plains …

An Approach To Hydrogeological Modeling Of A Large System Of Groundwater-Fed Lakes And Wetlands In The Nebraska Sand Hills, Usa, Nathan Rossman, Vitaly A. Zlotnik, Clinton Rowe

Department of Earth and Atmospheric Sciences: Faculty Publications

The feasibility of a hydrogeological modeling approach to simulate several thousand shallow groundwater-fed lakes and wetlands without explicitly considering their connection with groundwater is investigated at the regional scale (~40,000 km²) through an application in the semi-arid Nebraska Sand Hills (NSH), USA. Hydraulic heads are compared to local land-surface elevations from a digital elevation model (DEM) within a geographic information system to assess locations of lakes and wetlands. The water bodies are inferred where hydraulic heads exceed, or are above a certain depth below, the land surface. Numbers of lakes and/or wetlands are determined via image cluster analysis …

First U-Pb Zircon Ages For Late Miocene Ashfall Konservat-Lagerstatte And Grove Lake Ashes From Eastern Great Plains, Usa, Jon J. Smith, Elijah Turner, Andreas Moller, Robert M. Joeckel, Rick E. Otto

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper documents the first U-Pb zircon ages for Ashfall Fossil Beds (Nebraska, USA), a terrestrial Konservat-Lagerstatte mass-death assemblage that is arguably the most diverse of its type and age. The Ashfall tephra was correlated with ignimbrites from the Bruneau-Jarbidge volcanic field (12.7–10.5 Ma) in southwest Idaho based on geochemical analysis. The methods and geochemical data supporting the original age assessment of the ash bed, however, were never published, and there has been a persistent misconception that dateable heavy minerals (e.g., zircon) are absent. Notwithstanding, we recovered abundant zircons from Ashfall Fossil Beds, and from an ash bed ~6 km …

Sheeting Joints And Polygonal Patterns In The Navajo Sandstone, Southern Utah: Controlled By Rock Fabric, Tectonic Joints, Buckling, And Gullying, David B. Loope, Caroline M. Burberry

Department of Earth and Atmospheric Sciences: Faculty Publications

Sheeting joints are ubiquitous in outcrops of the Navajo Sandstone on the west-central Colorado Plateau, USA. As in granitic terrains, these are opening- mode fractures and form parallel to land surfaces. In our study areas in south-central Utah, liquefaction during Jurassic seismic events destroyed stratification in large volumes of eolian sediment, and first-order sheeting joints are now preferentially forming in these structureless (isotropic) sandstones. Vertical cross-joints abut the land-surface-parallel sheeting joints, segmenting broad (tens of meters) rock sheets into equant, polygonal slabs ~5 m wide and 0.25 m thick. On steeper slopes, exposed polygonal slabs have domed surfaces; eroded slabs …

Considerations For Atmospheric Measurements With Small Unmanned Aircraft Systems, Jamey D. Jacob, Phillip B. Chilson, Adam L. Houston, Suzanne Weaver Smith

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper discusses results of the CLOUD-MAP(Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics) project dedicated to developing, fielding, and evaluating integrated small unmanned aircraft systems (sUAS) for enhanced atmospheric physics measurements. The project team includes atmospheric scientists, meteorologists, engineers, computer scientists, geographers, and chemists necessary to evaluate the needs and develop the advanced sensing and imaging, robust autonomous navigation, enhanced data communication, and data management capabilities required to use sUAS in atmospheric physics. Annual integrated evaluation of the systems in coordinated field tests are being used to validate sensor performance while integrated into various sUAS platforms. This …

A Warm-Season Comparison Of Wrf Coupled To The Clm4.0, Noah-Mp, And Bucket Hydrology Land Surface Schemes Over The Central Usa, Matthew S. Van Den Broeke, Andrew Kalin, Jose Abraham Torres Alavez, Robert Oglesby, Q. Steven Hu

Department of Earth and Atmospheric Sciences: Faculty Publications

In climate modeling studies, there is a need to choose a suitable land surface model (LSM) while adhering to available resources. In this study, the viability of three LSM options (Community Land Model version 4.0 [CLM4.0], Noah-MP, and the five-layer thermal diffusion [Bucket] scheme) in the Weather Research and Forecasting model version 3.6 (WRF3.6) was examined for the warm season in a domain centered on the central USA. Model output was compared to Parameter-elevation Relationships on Independent Slopes Model (PRISM) data, a gridded observational dataset including mean monthly temperature and total monthly precipitation. Model output temperature, precipitation, latent heat (LH) …

The Future Of Evapotranspiration: Global Requirements For Ecosystem Functioning, Carbon And Climate Feedbacks, Agricultural Management, And Water Resources, Joshua B. Fisher, Forrest S. Melton, Elizabeth M. Middleton, Christopher Hain, Martha C. Anderson, Richard G. Allen, Matthew Mccabe, Simon Hook, Dennis Baldocchi, Philip A. Townsend, Ayse Kilic, Kevin Tu, Diego Miralles, Johan Perret, Jean-Pierre Lagouarde, Duane Waliser, Adam J. Purdy, Andrew French, David Schimel, James S. Famiglietti, Graeme Stephens, Eric F. Wood

Department of Earth and Atmospheric Sciences: Faculty Publications

The fate of the terrestrial biosphere is highly uncertain given recent and projected changes in climate. This is especially acute for impacts associated with changes in drought frequency and intensity on the distribution and timing of water availability. The development of effective adaptation strategies for these emerging threats to food and water security are compromised by limitations in our understanding of how natural and managed ecosystems are responding to changing hydrological and climatological regimes. This information gap is exacerbated by insufficient monitoring capabilities from local to global scales. Here, we describe how evapotranspiration (ET) represents the key variable in linking …

Dynamics Of Cloud-Top Generating Cells In Winter Cyclones. Part Iii: Shear And Convective Organization, Jason M. Keeler, Robert M. Rauber, Brian F. Jewett, Greg M. Mcfarquhar, Roy M. Rasmussen, Lulin Xue, Changhai Liu, Gregory Thompson

Department of Earth and Atmospheric Sciences: Faculty Publications

Cloud-top generating cells (GCs) are a common feature atop stratiform clouds within the comma head of winter cyclones. The dynamics of cloud-top GCs are investigated using very high-resolution idealized WRF Model simulations to examine the role of shear in modulating the structure and intensity of GCs. Simulations were run for the same combinations of radiative forcing and instability as in Part II of this series, but with six different shear profiles ranging from 0 to 10ms21 km21 within the layer encompassing the GCs.

The primary role of shear was to modulate the organization of GCs, which organized as closed convective …

Rear-Flank Outflow Dynamics And Thermodynamics In The 10 June 2010 Last Chance, Colorado, Supercell, Curtis J. Riganti, Adam L. Houston

Department of Earth and Atmospheric Sciences: Faculty Publications

On 10 June 2010, the second Verification of the Origins of Tornadoes Experiment (VORTEX2) armada observed a supercell thunderstorm near Last Chance, Colorado. Tempest unmanned aircraft system (UAS) data collected in the rear-flank outflow revealed what appeared to be an elevated outflow head, turbulent wake, and a cold rear-flank internal surge (RFIS). Surface thermodynamic and kinematic data collected by the StickNet and mobile mesonet indicated that the outflow wake may have extended to or very near the surface, perhaps modifying or outright replacing the leading edge of the outflow at times. Single-Doppler data collected by the NOAA X-Pol Mobile Polarimetric …

Fire And Smoke Remote Sensing And Modeling Uncertainties: Case Studies In Northern Sub‐Saharan Africa, Charles Ichoku, Luke T. Ellison, Yun Yue, Jun Wang, Johannes W. Kaiser

Department of Earth and Atmospheric Sciences: Faculty Publications

Significant uncertainties are incurred in deriving various quantities related to biomass burning from satellite measurements at different scales, and, in general, the coarser the resolution of observation the larger the uncertainty. WRF‐Chem model simulations of smoke over the northern sub‐Saharan African (NSSA) region for January–February 2010, using fire energetics and emissions research version 1.0 (FEERv1) aerosol emissions derived from MODIS measurements of fire radiative power (FRP) and aerosol optical depth (AOD), resulted in a severe model underestimation of AOD compared with satellite retrievals. Such uncertainties are attributable to three major factors: limitations in the spatial and temporal resolutions of the …

Crustal Distribution In The Central Gulf Of Mexico From An Integrated Geophysical Analysis, Irina Filina

Department of Earth and Atmospheric Sciences: Faculty Publications

This study addresses the question of the crustal composition in the central part of the northern Gulf of Mexico (GOM) – the region of the major disagreement between published tectonic models. The location of the Ocean-Continental Boundary (OCB) for different tectonic models varies within 140 km (87 mi) in the study area. I have developed a 2D model integrating the seismic reflection and refraction data with potential fields (gravity and magnetics) along the profile through the debated region. Two alternative OCB locations were tested. The preferred model suggests the OCB position near the Sigsbee Escarpment, which is in agreement with …