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Full-Text Articles in Physical Sciences and Mathematics

Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi Dec 2016

Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi

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

Quantitative analysis for the Lower Miocene of Ocean Drilling Program Hole 959A from the West African margin was performed to document all the calcareous nannofossil biostratigraphic events present. Combined with data from previous investigations of the Lower Miocene from the tropical Atlantic, this research identifies and tests the viability of markers used in current zonation scheme, identifies alternative markers for age boundaries, and examine statistically the most probable order of event in the Lower Miocene using the Ranking and Scaling method (RASC).

The examination of Hole 959A was performed on a 112 samples. Seven additional sites that collectively span the …


Influence Of Land Cover Type And The Reliability Of Selected Land Surface Models: A Comparison Of Wrf Version 3.6 Coupled To Clm Version 4.0, Noah-Mp, And The Bucket Hydrology, Andrew J. Kalin Nov 2016

Influence Of Land Cover Type And The Reliability Of Selected Land Surface Models: A Comparison Of Wrf Version 3.6 Coupled To Clm Version 4.0, Noah-Mp, And The Bucket Hydrology, Andrew J. Kalin

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

In this study, the validity of 3 LSMs (Community Land Model version 4.0, Noah-MP and the Budyko Bucket Hydrology model [henceforth referred to as ‘Bucket model’]) coupled with the Weather Research and Forecasting model version 3.6 (WRF3.6), was examined in an effort to show the associated strengths and weaknesses of each LSM. This objective was completed by first, developing expected results based on a simple surface energy budget calculation, and by later comparing model output to Parameter-elevation Relationships on Independent Slopes Model (PRISM) data, which serve as gridded observed values of mean monthly temperature and total monthly precipitation. Model output …


Spatial Continuous Biomass Burning Emission Inventory: Application To Wrf-Chem Model Over The Northern Sub-Saharan African Region, Yun Yue Nov 2016

Spatial Continuous Biomass Burning Emission Inventory: Application To Wrf-Chem Model Over The Northern Sub-Saharan African Region, Yun Yue

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

Fire, as a significant global source of trace gases and aerosol particles, plays an important role in perturbations of the chemical and physical properties of the atmosphere. Fire products from Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on polar-orbiting satellites Terra and Aqua are largely used in several emission inventories. However, the MODIS fire products have inherent limitations due to the following reasons: (a) they cannot detect fires underneath clouds; (b) the fire detection sensitivity decreases at the edge of MODIS scan where viewing angles and MODIS pixel sizes are bigger than at nadir; and (c) there are gaps between MODIS …


Stratigraphy And Sedimentology Of The Cretaceous Mowry Shale In The Northern Bighorn Basin Of Wyoming: Implications For Unconventional Resource Exploration And Development, Jordan M. Bremer Jul 2016

Stratigraphy And Sedimentology Of The Cretaceous Mowry Shale In The Northern Bighorn Basin Of Wyoming: Implications For Unconventional Resource Exploration And Development, Jordan M. Bremer

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

The Mowry Shale (Albian-Cenomanian) is an extensive mudrock dominated unit historically believed to represent a single, long-term deep water sequence within the Western Cordilleran Foreland Basin of North America. While the Mowry Shale has received study for almost a century, detailed stratigraphic context is still lacking. Such an understanding will be required as the formation is increasingly explored as an unconventional resource play.

This study examines the stratigraphy of the interval between the Muddy sandstone and the Frontier Formation, focusing on the Mowry Shale both at outcrop and in the subsurface of the Bighorn Basin of northwestern Wyoming. Detailed measured …


Santonian—Campanian Calcareous Nannofossil Paleobiogeography, Brandi R. Moore Jul 2016

Santonian—Campanian Calcareous Nannofossil Paleobiogeography, Brandi R. Moore

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

Calcareous nannofossil abundance data from 11 DSDP/ODP sites were analyzed by multivariate methods to assess the paleoceanographic change that is associated with the Santonian-Campanian boundary transition. Data were divided into Santonian or Campanian age groups based on the presence or absence of the lower Campanian nannofossil species, Aspidolithus parcus parcus. All assemblages are dominated by Watznaueria barnesiae, Micula decussata, and Prediscosphaera intercisa. Analyses determined that the relative abundance of M. decussata generally reflects a change in temperature, with a preference for cool water. Prediscosphaera intercisa appears to have had an inverse abundance relationship with M. decussata, suggesting that …


Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang Jul 2016

Reconstructing The Paleoecology And Biogeography Of Rhinoceroses (Mammalia: Rhinocerotidae) In The Great Plains Of North America, Leading Up To Their Extinction In The Early Pliocene, Bian Wang

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

Members of the family Rhinocerotidae first appeared in the middle Eocene and were one of most successful mammal groups of the Oligocene and Miocene in North America. Their extinction in the early Pliocene has been attributed to several causes, including cooling climate, an expansion of C4 grasslands, and faunal turnover favoring high-crowned, open habitat-adapted mammalian taxa. This study tests whether the extinction of North American rhinoceroses in the Great Plains was abrupt or gradual by examining changes in their paleogeographic distribution in a series of time-slices through the Barstovian, Clarendonian, and Hemphillian North American land-mammal ages. It further examines …


Modeling And Satellite Remote Sensing Of The Meteorological Impacts Of Irrigation During The 2012 Central Plains Drought, Clint Aegerter Jun 2016

Modeling And Satellite Remote Sensing Of The Meteorological Impacts Of Irrigation During The 2012 Central Plains Drought, Clint Aegerter

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

As irrigation is increasingly needed for agricultural production, it is becoming progressively more important to understand not only how irrigation impacts water availability, but how the introduction of this water into the soil impacts weather and climate through land-atmosphere interactions. In the summer of 2012, the Central Plains of the United States experienced one of its most severe droughts on record. This study examines the meteorological impacts of irrigation during this drought through observations and model simulations using the Community Land Model (CLM) coupled to the Weather Research and Forecasting (WRF) model. A simple parameterization of irrigation processes is added …


Differing Roles Of The Great Plains Low-Level Jet In Producing Warm Season Precipitation Over The Central United States In 2002, Mengyuan Shang May 2016

Differing Roles Of The Great Plains Low-Level Jet In Producing Warm Season Precipitation Over The Central United States In 2002, Mengyuan Shang

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

The purpose of this research is to describe and compare different roles of the Great Plains low-level jet (GPLLJ) in producing warm season precipitation over the central United States by model simulation. After going through 35 years’ (from 1979- 2013) NCEP North American Regional Reanalysis (NARR) data, year 2002 was selected for model simulation as it contained a “wet period” (May- June) and a “dry period” (July- August). The model simulation was done by using Weather Research and Forecasting (WRF) Regional Model. In this study, the GPLLJ was defined by the low-level wind at 925 hPa. The results showed the …


Upper Albian To Lower Cenomanian Calcareous Nannofossil Biostratigraphy Of The Proto-North Atlantic, Shamar Chin Apr 2016

Upper Albian To Lower Cenomanian Calcareous Nannofossil Biostratigraphy Of The Proto-North Atlantic, Shamar Chin

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

Lower Cenomanian calcareous nannofossil assemblages from Deep Sea Drilling Project (DSDP) Sites 137 and 547 in the proto-North Atlantic Ocean were analyzed quantitatively to examine the fidelity of the widely used CC and UC calcareous nannofossil Zonal schemes. Datasets from Ocean Drilling Program (ODP) holes 1050C and 1052E (Blake Nose) and Tanzania Drilling Project (TDP) Site 24 were integrated into this dataset. Four biozones spanning the upper Albian through middle Cenomanian were determined using the method of unitary associations (UA). Data were also used from these sequences to generate a ranking and scaling (RASC) optimum sequence. A new reliability index …


Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator, Evan Whiting Apr 2016

Constraining Neogene Temperature And Precipitation Histories In The Central Great Plains Using The Fossil Record Of Alligator, Evan Whiting

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

Most amphibians and reptiles (excluding birds) are poikilothermic; their internal body temperature varies with that of their external environment. This makes them useful as climate proxies, especially when linked to geographic distributions of ambient climate. I evaluate the utility of the extant crocodylian genus Alligator as a paleoclimate proxy for the Central Great Plains (CGP) using species distribution modeling. Alligator is a readily identifiable taxon with a good CGP fossil record during the Neogene (~23–2.6 Ma). Alligator first appeared in the CGP in the late Eocene (~37 Ma), was absent during most of the Oligocene, reappeared in the early Miocene …


Concepts About Sedimentology And Stratigraphy In Undergraduate Geoscience Courses, Bailey Z. Kreager Apr 2016

Concepts About Sedimentology And Stratigraphy In Undergraduate Geoscience Courses, Bailey Z. Kreager

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

This two-part study examines sedimentologic and stratigraphic concepts in undergraduate geoscience courses. The first part seeks to identify the various types of interactive engagement strategies used in undergraduate science courses, how they are used and in what fields. It also looks at areas in which the geosciences have excelled in interactive engagement strategies. Published studies describing interactive engagement strategies in college-level courses were collected and coded, which identified six emergent types of interactive engagement strategies: (1) Polling, (2) Full-Class Discussion and Activities, (3) In-Class Group Work, (4) Out-Of-Class Group Work, (5) Online Work, and (6) Other types. Interactive engagement strategies …


Effects Of Meteorological Conditions On Sulfur Dioxide Air Pollution In The North China Plain During Winter Of 2006-2015, Chase C. Calkins Mar 2016

Effects Of Meteorological Conditions On Sulfur Dioxide Air Pollution In The North China Plain During Winter Of 2006-2015, Chase C. Calkins

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

The last decade has seen frequent occurrences of severe air pollution episodes of high concentration in SO2 during winters in the North China Plain (NCP). Using satellite data from the Ozone Monitoring Instrument (OMI), chemistry transport model (GEOS-Chem) simulations, and National Center for Environmental Predication (NCEP) meteorological reanalyzes, this study examines meteorological and synoptic conditions associated with these air pollution episodes during winters of 2006-2015. OMI-based data suggest a large decrease (~30% in area average) of emission since 2010. Statistical analyzes show that meteorological conditions associated with the top 10% of OMI-based high days are found in average to …