WorldCat Identities

Indiana University, Bloomington Department of Earth and Atmospheric Sciences

Overview
Works: 32 works in 32 publications in 1 language and 105 library holdings
Genres: Academic theses 
Publication Timeline
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Most widely held works by Bloomington Indiana University
Reduced-order modeling for estimating CO₂ storage and enhanced coalbed methane of unconventional coal seam reservoirs by Ryan Kammer( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

We compare CO2 storage and utilization resource estimates from SCO2T-ECBM with regional estimates from static, volumetric models. The results indicate that static models may be overly optimistic, particularly in the mid- and high-range estimates. This result is consistent with other studies that have compared static estimates with dynamic simulations, and may suggest a re-evaluation of CO2 storage and utilization resource estimates is needed. SCO2T-ECBM has promise as a useful tool in generating CO2 storage and utilization resource estimates to aid in the deployment of CCUS technology
Characterizing deformation in precambrian gneisses along the Carmichael fault, SW Montana : implications for modeling fault cross sections and Laramide lithospheric fault behavior by Ciara Morgan Mills( )

1 edition published in 2017 in English and held by 8 WorldCat member libraries worldwide

The Laramide Carmichael fault is exposed as a basement involved NW-trending left lateral reverse fault in the northern Tobacco Root Mountains in the Rocky Mountain foreland in southwestern Montana. Archean gneisses and Paleozoic -- Mesozoic sedimentary units are displaced and deformed along this fault. The Pole Canyon anticline is a fault propagation fold related to the Carmichael fault with a fold axis trending northwest. Folds within Archean gneisses in the anticline and in the vicinity of Indiana University's Judson Mead Geologic Field Station (IUGFS) trend north, indicating that the foliation within the gneisses formed during a different deformation event
Faunal dynamics in response to quaternary climate cycling : a physiographic regional approach by Michael R Smith( )

1 edition published in 2017 in English and held by 8 WorldCat member libraries worldwide

Projected global warming has heightened interest in biologic response to climate change. The Pleistocene epoch, with its cycles of alternating cold glacial periods and warm interglacial periods represents an ideal case study for examining how faunas have responded to climate change. Fossil mammals in the Pleistocene are abundant and aare extant or have closely related living relatives
Geological examination of archaeological middens in the Dominican Republic by Kathryn D Nold( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

My research applies traditionally geochemical and paleontological approaches to investigate important and ongoing areas of scientific inquiry in the Caribbean, principally recent climatic patterns, the status of important biological coastal resources, and the island's original residents who experienced the beginning of American colonialism. This dissertation examines study sites on the north and south shores of the Dominican Republic, encompassing both Atlantic and Caribbean coastal environments, El Tamarindo on the northwest coast and La Cangrejera on the southeast coast. Radiometric dates established a temporal datum from which I built this investigation into the paleoecology, paleoclimate, and archaeology of the Dominican Republic. Carbon and oxygen stable isotope analyses of select marine gastropods serve as proxies of shallow marine sea-surface temperatures during the molluscs' lifetimes, and by extension, expands the environmental parameters of the late Holocene record for the neotropics. Taxonomic identifications of 11,570 bivalve and gastropod individuals and 5,472 body size measurements facilitated reconstruction of the paleoecology of these shallow-water coastal sites and established baselines for coastal resources in the Dominican Republic before the arrival of Europeans. The elemental composition of ceramics found excavated with the thousands of mollusc shells were analyzed to determine their elemental relationship to other ceramics from the region and geologic sources. The results of this investigation indicated proximity to geologic provinces is a significant factor in the elemental composition of ceramics instead of typological motifs. I anticipate this approach will yield significant insight into movement and interaction of prehistoric peoples as the elemental database for Caribbean ceramics expands. The interdisciplinary approach explored in this dissertation highlights the significant contributions facilitated through integration of geologic and archaeological methods to approach diverse questions from the peopling of the Americas to conservation of tropical coasts and Quaternary climate patterns
Characterization of extensional tectonics in North Boulder Basin, Montana, through detailed analysis of longitudinal stream profiles by Donald Tripp( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

This research was conducted in the southern ~92 km2 area of the North Boulder basin, which contains nine tributaries that flow westward over a north-south striking normal fault scarp into the North Boulder River. The goal of this study was to be able to quantify the spatial distribution and magnitude of base level changes that influenced the evolution of North Boulder River tributaries by using normalized steepness indices, and total river incision taken from relict profile reconstructions based off the Stream-Power Limited Detachment model. An additional goal was to place events that shaped the stream profiles into a temporal context by determining exposure ages along the major normal fault scarp over which the streams flow by testing for cosmogenic 36Cl isotopes. Each of the tributary stream beds contain a wide variation of lithologies unique to each stream. While several stream flow almost entirely over homogenous limestone bedrock of the massively bedded Mississippian Mission Canyon formation, other streams flow over numerous lithological changes that range in age from the pre-Cambrian to the Tertiary consisting of sandstones, carbonates, siltstones, and shales. The tool set used to determine normalized steepness indices and reconstruct relict profiles for total incision values consisted of 1) Post Processing Kinematic surveys, 2) 10 meter DEMs obtained from USGS, 3) watershed tools in Arc GIS, 4) TopoToolbox 2 MATLAB scripts, and 5) USGS topographical maps. The Prime Labs facility processed limestone samples extracted from a vertical section of the normal fault scarp and the results were inputted into CRONUS in order to determine exposure ages so that timing and magnitude of base level changes could be determined. Not only was a tectonic boundary able to be quantitatively determined, but results obtained from these methods indicate that when placed in context of the shear-stress/stream-power model, tectonic forcing superseded the influences of rock strength and drainage area that shaped the stream profiles over at least the past ~47 k.y
Multiple sulfur isotope study assessing contributions of crustal sulfur to the Eagle East Ni-Cu-PGE deposit, Marquette County, northern Michigan by Erin Benson( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

The Eagle East intrusion, located near Marquette, Michigan, was emplaced into the Baraga Basin early in Midcontinent Rift System formation. This deposit is a conduit-style, high-grade Ni-Cu-[PGE] deposit hosted by feldspathic peridotite and olivine melagabbro. For most magmatic Ni-Cu-PGE deposits the assimilation of S from country rocks has been a key process in the generation of sulfide-rich ores. Ni grades of up to 8% present in the East Eagle deposit suggest that sulfide saturation was attained early in the magma crystallization sequence, before Ni was sequestered by olivine. This strongly indicates that some S originated from the country rocks of the Baraga Basin; either Paleoproterozoic sedimentary rock or Archean basement rock. Multiple sulfur isotope analyses of sulfide minerals, primarily pyrrhotite, chalcopyrite, and pentlandite, from Eagle East were conducted for all mineralization types. delta34S values (1.5%₀ to 16%₀) suggest a significant amount of S in the deposit originated from Paleoproterozoic rocks. However, Delta33S values ( --0.07%₀ to 0.05%₀) are not suggestive of the involvement of S from Archean rocks. delta 34S and Delta33S values closer to zero at Eagle East may indicate that S isotopic exchange in the conduit with uncontaminated mantle-derived magma occurred, leading to lower isotopic ratios closer to those of pristine mantle S (near 0%₀)
Monitoring and detecting transient deformation in Western Taiwan using dense GPS arrays and the network strain filter by Chian-Heng Lee( )

1 edition published in 2017 in English and held by 8 WorldCat member libraries worldwide

We compute the time-dependent horizontal transient deformation field of western Taiwan from 2006 to 2016 using time series data from 196 continuous GPS stations. Spatially and temporally coherent transient signals are identified by analyzing data from the entire geodetic networks simultaneously using the Network Strain Filter developed by Ohtani et al. [2010]. The filter separates spatially coherent transient deformation from steady secular rates, seasonal variations, and site-specific noise. In the eleven-year time span, six transient deformation patterns are observed. Comparison with calculated postseimsic displacements following known earthquakes with similar fault geometries suggest that three of the transients are the result of postseismic afterslip and/or viscoelastic mantle flow in response to the 1999 Chi-Chi earthquake, the 2010 Jiashian earthquake and the 2013 Nantou earthquake series, respectively. Two identified island-wide transient events in 2012 and 2016 are not associated with large earthquakes and the mechanisms behind the deformation are still not clear. A localized transient event in southwestern Taiwan occurs near the source area of the 2010 Jiashian earthquake and precedes the earthquake by four years. Our results suggest that transient crustal deformation is prevalent in Taiwan in the form of postseismic and other aseismic events. Future work incorporating the vertical component of GPS time series and expanding the study area to the whole island will allow for a more complete view and understanding of the transient deformation field of Taiwan
Seismicity of the Wabash Valley, Ste. Genevieve, and Rough Creek Graben seismic zones from the Earthscope Ozarks-Illinois-Indiana-Kentucky (OIINK) FlexArray experiment by Matthew Richard Shirley( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

I analyzed seismic data from the Ozarks-Illinois-Indiana-Kentucky (OIINK) seismic experiment that operated in eastern Missouri, southern Illinois, southern Indiana, and Kentucky from July 2012 through March 2015. A product of this analysis is a new catalog of earthquake locations and magnitudes for small-magnitude local events during this study period. The analysis included a pilot study involving detailed manual analysis of all events in a ten-day test period and determination of the best parameters for a suite of automated detection and location programs. I eliminated events that were not earthquakes (mostly quarry and surface mine blasts) from the output of the automated programs, and reprocessed the locations for the earthquakes with manually picked P- and S-wave arrivals. This catalog consists of earthquake locations, depths, and local magnitudes. The new catalog consists of 147 earthquake locations, including 19 located within the bounds of the OIINK array. Of these events, 16 were newly reported events, too small to be reported in the Center for Earthquake Research and Information (CERI) regional seismic network catalog. I compared the magnitudes reported by CERI for corresponding earthquakes to establish a magnitude calibration factor for all earthquakes recorded by the OIINK array. With the calibrated earthquake magnitudes, I incorporate the previous OIINK results from Yang et al. (2014) to create magnitude-frequency distributions for the seismic zones in the region alongside the magnitude-frequency distributions made from CERI data. This shows that Saint Genevieve and Wabash Valley seismic zones experience seismic activity at an order magnitude lower rate than the New Madrid seismic zone, and the Rough Creek Graben experiences seismic activity two orders of magnitude less frequently than New Madrid
Floodplain morphodynamics : the origin and function of floodplain channels by Scott Robert David( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

River floodplains are a key human habitat that provide rich, fertile soils for agriculture, and are among the most productive ecosystems on Earth. Despite the ecological and economic importance of floodplains, most hydrologic and geomorphic models of meandering river floodplains oversimplify them as relatively flat, featureless deposits adjacent to a river channel. Recent high resolution topography data reveals that floodplains are remarkably complex and often contain channel networks carved into their floodplain (floodplain channels). Understanding the origin, function and evolution of floodplain channels is important to understanding floodplain dynamics. The presence of floodplain channels suggests that floodplains are not passive depocenters as depicted in standard models of floodplain sedimentation, but have their own set of processes independent of the main channel
Earthquakes and aseismic creep associated with fault-related folding by Carrie Burke( )

1 edition published in 2018 in English and held by 8 WorldCat member libraries worldwide

Active blind faults under growing anticlines pose a seismic hazard that is particularly difficult to assess because the faults do not intersect the Earth's surface. Densely populated areas like Japan, western Taiwan, and Los Angeles are all prone to earthquakes occurring on blind faults. In this study, we begin to improve our understanding of the hazard associated with these structures by computing how much fold growth is seismic versus aseismic and how much slip occurs on the fault or distributed through the fold. We use a mechanical model of folding from Johnson (2018) to simulate slip and deformation on a fault. We ran sixteen total simulations using a variety of fold-fault geometries and used the simulation outputs to calculate and quantify on and off-fault slip attributes. We categorize slip as earthquake, afterslip, or spontaneous creep events, determined the percentage of seismic (earthquake) and aseismic (afterslip and spontaneous creep) events, and calculated earthquake magnitude. We find that spontaneous creep events are distributed through both the velocity weakening and strengthening zones of the fold. Earthquake slip largely occurs on ramp faults and on long, straight bedding surfaces of the backlimb and do not rupture through the fold hinge. Larger earthquakes occur on the fault, straight limb segments, and nearly horizontal layers. Straight faults rupture mostly large M6+ earthquakes while curved faults rupture in smaller events as well as large earthquakes. Forelimbs of the fold slip almost entirely aseismically, as spontaneous creep events or as afterslip. Afterslip often occurs on both limbs of the anticlines following large earthquakes. Seismic events make up 38--92% of total slip while aseismic events make up 8--62%. While, there is no clear relationship seen between fold-fault geometry and the percentage of seismic versus aseismic slip, larger amplitude folds tend to have more aseismic slip than smaller amplitude folds
A hydrological model of the Wabash River watershed for assessing and managing water resources in Indiana by Anas B Rabie( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

The Soil and Water Assessment Tool (SWAT) was evaluated for its ability to simulate and analyze the hydrology of the 85,560 km2 Wabash watershed that is shared by the states of Ohio, Indiana, Illinois, and Kentucky in the Midwest region of the United States. The data employed in the analysis are available to the public from trusted organizations, e.g., the USGS, MRLC, etc. The purpose of this study is to 1) create a hydrological model for the Wabash watershed, and 2) to conduct detailed analyses of the output data, especially during the spring season, to study potential spring season flooding. The data used for these analyses are precipitation, temperature, Soil Water Yield, surface runoff, and snow melt. The basin was divided into 516 subbasins based on the DEM data and a threshold area of 9,000 ha. A total number of 2,803 Hydrologic Response Units (HRU) that represent the different soil types and land use was generated, according to the soil, land use maps and slope with threshold values of 20%, 10%, and 20%, respectively. The first five years were used as the warm-up period to mitigate the effect of initial conditions. The calibration was carried out at daily time steps using flow data from January 2003 to December 2009. The years from 2010 to 2013 were used for validation. SWAT-CUP (a calibration/uncertainty or sensitivity program interface for SWAT) was used. In this study, the sequential uncertainty fitting algorithm (SUFI-2) procedure was used for parameter optimization and uncertainty propagation analysis. The main findings of this study are: 1) The areas adjacent to the main channel are the most affected, with higher concentrations downstream, 2) Differences in Land Use and Land Cover type (LULC) do not have a significant influence on the results, and 3) high peak precipitation events did not have a significant contribution to flooding due to an increase in temperatures during the same times those peaks occurred
Organic matter accumulation, thermal maturation, and organic pores development in the upper Devonian New Albany shale, Illinois basin by Bei Liu( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

Organic matter (OM) quantity, quality, and thermal maturity are key parameters in both conventional and unconventional petroleum systems. Understanding the stratigraphic distribution of OM content and type in black shale successions and its transformation during thermal maturation is of great significance in source rock evaluation and unconventional shale oil/gas exploration and development. In this study, organic petrography, scanning electron microscopy (SEM), micro-Fourier transform infrared spectroscopy, portable x-ray fluorescence spectroscopy, and inductively coupled plasma-mass spectrometry techniques were used to study the heterogeneity of OM in the Upper Devonian New Albany Shale (NAS) in the Illinois Basin. Specifically, this research aims to (1) document the distribution of total organic carbon content (TOC) content and maceral types in the sequence stratigraphic context of the NAS; (2) study the association of uranium (U) with organic matter and maceral types; (3) document the transformation of oil-prone macerals and characterize the evolution of the chemical structure of macerals and solid bitumen (SB) during thermal maturation across a maturation gradient from vitrinite reflectance (Ro) 0.55% to 1.42%; and (4) examine the control of thermal maturity and maceral type on the development of secondary organic pores using correlative microscopy (SEM and reflected-light microscopy). The results show that within a sequence stratigraphic context, TOC content increases in transgressive systems tracts, reaches a maximum just below maximum flooding surfaces, and shows relatively low values in highstand systems tracts. Bottom-water redox conditions are one of the controlling factors for OM enrichment in the NAS. U in the NAS is mainly associated with sedimentary OM. Amorphous organic matter (AOM) derived from degraded phytoplankton, zooplankton, and bacterial biomass is the primary host of U in the NAS. Alginite and terrestrial OM have negligible contributions to whole-rock U content. Different macerals follow specific evolutionary pathways over the course of thermal maturation. AOM and alginite disappear at thermal maturities of Ro 0.80% and 0.89%, respectively. SB becomes the dominant OM above a maturity level of Ro 0.80% as oil-prone macerals such as AOM and alginite are converted to hydrocarbons and solid bitumen. Terrestrial OM (vitrinite and inertinite) does not show significant changes in morphology and occurrence with increasing thermal maturity due to their low hydrocarbon generation potential. Organic pores in the NAS can be primary as well as secondary. Primary organic pores are cellular pores derived from cell lumens in terrestrial plant fragments. Secondary organic pores (< 1000 nm) are SB-hosted and their formation is controlled by both thermal maturity and maceral type
Variability of tropical cyclone intensity forecasts in the COAMPS-TC model by Cole Evans( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

As part of an effort to quantify the intrinsic error that exists in the Coupled Ocean and Atmospheric Mesoscale Prediction System - Tropical Cyclone (COAMPS-TC) model, intensity variability in the model was analyzed in this study, using the retrospective 2015-2018 data from three major ocean basins, as well as idealized simulations. Forecast data generated by the FY2018 version of COAMPS-TC was compared to best-track data and then stratified into different groups based on track error, stemming from both its GFS input and its own track errors. This forecast verification analysis revealed that reducing 5-day track errors from 300 to 100 nm (~50-70%) can help reduce the absolute intensity errors by 18-20%, with the largest error reductions more pronounced during 4 to 5-day lead times. For cases in which the track error can be reduced to 80 nm or less, a limit at which track errors can be reduced before intensity forecast errors no longer decrease is revealed, with 4 to 5-day intensity errors saturating to around 10-12 kt. Such a finding reveals that some inherent source of error for intensity forecasts exists in the model. Idealized ensemble experiments were then conducted in order to further quantify the dependence of TC intensity errors on the large-scale environment. Results revealed that the model possesses an intrinsic intensity variation in the range of 4-5 kt, with no universal value as it depends on the storm's ambient environment. This finding is consistent with other TC forecasting models in similar studies, revealing both the influence chaotic dynamics have on TC intensity forecast errors, and the limit at which forecast errors within a numerical model could theoretically be reduced to. Analyses of the TC structure at the onset of rapid intensification confirm that the low troposphere moisture structure plays a key role in the timing of TC rapid intensification in the COAMPS-TC model
Using novel array methods to search for solar modes in the seismic background and test a geomagnetic sun-solid earth coupling mechanism by Ross C Caton( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

The aim of this dissertation is to search for a solar source in the seismic background. Previous studies have found evidence for solar oscillations in the seismic background but were limited to single-station datasets. In this study I stack seismic array data to reduce noise and exploit redundancy to distinguish coherent signals from the background. I present new methods for combining array data and improving signal-to-noise ratio (SNR). These include a robust stacking algorithm that ignores outliers, a jackknife method that estimates the variance of the spectrum, an algorithm that removes impulsive transient signals, and a method for estimating the significance of a spectral band. I demonstrate the effectiveness of these on real and synthetic data and use them to search for solar modes in seismic noise. I use data from the Homestake Mine 3-D array, the Pinon Flats borehole array, and the Austrian Seismic Network because of their low noise level. I found several harmonic lines with high statistical significance that match the empirical or theoretical frequencies of solar p-modes. I also identify several bands at ultra-long-periods that possess statistical properties consistent with the presence of many closely spaced lines, which I interpret as solar g-modes. I test the hypothesis that the solar oscillations couple to the Earth through the geomagnetic field by examining the magnitude-squared coherence (MSC) between the Homestake Mine 3-D array and geomagnetic data from an observatory in Boulder, Colorado. An estimate of the MSC based on the percentiles of 100 week-long blocks resembles previous results that were interpreted as solar modes. Additionally, the distribution of 601 ~1-day MSC blocks is significantly different than a zero-coherence model. These observations are consistent with the solar mode results and demonstrate a previously unobserved relationship between the seismic background and geomagnetic fluctuations
Characterization of Stream Channel Evolution Due to Extensional Tectonics Along the Western Margin of North Boulder Basin (Bull Mountain), SW Montana by Kirstyn A Cataldo( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

Landscape response to active tectonics, such as fault motion or regional uplift, can be recorded in river profiles as changes in slope (i.e. knickpoints) or topography. North Boulder basin region (SW Montana), experienced two separate phases of extension, from 45 - 35 Ma and again beginning ~14 Ma to the present. Focusing on the Bull Mountain region, located on the western margin of the North Boulder basin, data was collected to elucidate the active tectonics of the study area by utilizing river profile analysis and thermochronometric data. High-resolution (< 5cm) river profile data was obtained from five of the main tributaries of Bull Mountain. Comprehensive geologic mapping along the main tributaries and topographic highs of the region allowed for the identification of knickpoints, composition of lithologic descriptions, and analysis of key structural features.^
Paleoenvironmental Biogeochemical Signal Integrity: How in situ Environmental Degradation and Post-collection Sediment Storage Conditions affect Molecular Compositions and Impact Reconstructions by Andrea M Shilling( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

This dissertation contributes to the understanding of biogeochemical proxies as tools for reconstructing paleoenvironments. When compared to well-established proxies (e.g. pollen and macrofossils), biomarkers are a relatively new field, some aspects of which have not been thoroughly explored, such as environmental degradation and sample alteration during storage. This dissertation focuses on the use of biogeochemical proxies preserved in lacustrine sediments from Olduvai Gorge, Tanzania to reconstruct the paleoenvironment encountered by early hominins. Additionally, a two-year study was completed to examine the molecular impact of common sediment storage practices and potential for sample alteration during storage. Two chapters of this dissertation concentrate on the use of biogeochemical proxies preserved within lacustrine sediments from Olduvai Gorge, Tanzania to reconstruct changes in the paleoenvironment over ~50,000 years. Previous studies in this region had examined samples collected from outcrops, which are less suitable for biogeochemical analyses due to weathering and degradation compromising the original record. The core material examined here allowed for more extensive biomarker analyses during a time of considerable environmental change. Within the section of core, there was evidence of degradation that occurred after deposition but prior to collection, indicating that all core samples are not without limitations. This study allowed for the comparison of biogeochemistry records in highly preserved versus poorly preserved core material. Additional biogeochemical analyses on the core section with superior preservation showed the environmental response to precession scale climate changes, indications of increasing aridity, and greater climate variability than previously recorded, which all would have impacted hominin evolution. For most paleoenvironmental proxies, post-collection sample alteration is of minimal concern, however, this is not the case for biomarkers. While it is known that care must be taken to avoid contamination during collection, little consideration is given to sample alteration occurring during storage. Any changes in the molecular composition after collection can obscure the original paleoclimate or paleoenvironmental signal, compromising reconstructions. This chapter examined sediment samples prior to and after two years stored under a variety of conditions, to identify affected biomarkers and the conditions that caused the greatest change over the two-year period
Experimental evaluation of gas genesis and alteration of petroleum source rocks using: organic geochemistry, stable carbon and sulfur isotopes, and raman spectroscopy by Mohammad Abdulazim Alrowaie( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

A look at the statistical relationship between the largescale tropospheric static stability and hurricane maximum intensity by Alexandria Downs( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

This thesis will take you through my examination of how stratification has previously affected hurricane intensities. Various modelling and observational studies have suggested that tropical cyclone (TC) intensity tends to increase in the future due to the projected warmer trend of sea surface temperature (SST). This study examines a different environmental factor associated with the stratification of the troposphere that could potentially offset the direct increase of TC intensity associated with warmer SST. Statistical analyses derived from the NCEP reanalysis for the two major ocean basins reveal a significant negative correlation between annually averaged TC intensity and the tropospheric static stability during 1948-2017. The resulting statistics is particularly strong for the TC lifetime maximum intensity in the northwestern Pacific basin, but is somewhat less significant in the north Atlantic basin. Given a projection of a more stable troposphere in a warmer climate, the inimical contribution of the more stable troposphere to the TC intensity as obtained in this study could negate some of the projected increase in the upper bound of the TC maximum potential intensity due to increasing SST, thus suggesting the significant role of the tropospheric static stability in the TC intensity variability that one needs to take into account in studies of TC-climate relationship
Chracterization and remediation of fugitive hydrocarbon emissions from Indiana oil/gas wells into the atmosphere by Yidong Yin( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

Regional studies in the USA indicate that hydrocarbon gas emissions from active, inactive, and improperly sealed and abandoned oil/gas wells contribute significantly to anthropogenically emitted greenhouse gases, predominantly in the form of methane. There are more than 80,000 active, inactive, plugged and abandoned oil/gas wells in Indiana. Their fugitive methane emissions have not been quantified. This study is a first attempt to (i) explore the extent of hydrocarbon gas emissions from oil/gas wells in Indiana and (ii) to evaluate microbial strategies to mitigate those hydrocarbon emissions into the atmosphere. We investigated 20 active, inactive and plugged-abandoned oil/gas wells across Monroe, Daviess and Sullivan counties in Indiana. An active gas well with fugitive methane emissions in the order of liters per hour in Monroe County was used as a research site for this study. Methane emissions were measured repeatedly using a static flux tent under different weather conditions. We found that the methane concentration in the tent initially increased linearly with time at an average methane leakage rate of approximately 2 L h-1. Microbial methanotrophs are widely known to metabolize methane in soils, especially strongly in areas with seepage of methane. Soils adjacent to the leaking well and control soils 20 m away from the well were deployed in mesocosm experiments to evaluate their comparative methanotrophic activities. During mesocosm experiments at room temperature over 138 hours, 4 g of soil from close to the well consumed 96.9 % of the 0.5 mL methane that had been added to the headspace of a 70-mL glass culture bottle, while the same amount of control soil from 20 m away consumed only 14.4 % of added methane. The data demonstrate that soils adjacent to the leaking well exhibited higher methanotrophic activity than control soil from a distance. We also found that prolonged exposure of soil methanotrophs to elevated concentrations of methane enhanced the methanotrophic activity. Finally, we experimentally tested the feasibility of a "methanotrophic soil mound" using an artificial point source of methane placed under the soil and found the methanotrophic mound could sustainably mitigate the methane emission. The methanotrophic activity of methanotrophs in the experimental soil mound decreased when soil temperature increased from 20.5 & deg;C to 30.5 & deg;C over 16 days. Methanotrophic soil mounds should employ methanotrophic microbial consortia that are adapted to the local climate
The paleoecology of patriofelis ulta and implications for oxyaenid extinction by Anne E Kort( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

Oxyaenids were one of three diverse clades of terrestrial mammalian carnivores in the Eocene: carnivorans survive to the present day, hyaenodontids persisted into the Miocene, but oxyaenids became extinct in the Eocene. Key adaptations may have inflexibly coupled oxyaenids to disappearing tropical environments. An almost complete specimen of Patriofelis ulta, one of the last oxyaenids in North America, shows an unusual combination of postcranial features, including short limbs and inflexible lumbar vertebrae. I used a CT scan to observe the specimen and make observations on features related to locomotion in comparison with extant mammals. I focused on the unusual lumbar vertebrae with inflexible, revolute zygopophyseal joints, unlike anything found in modern carnivorans. I used geometric morphometrics to compare the shape of this joint with those of 20 extant mammals from 9 orders. Ten landmarks were used to measure overall shape of the vertebrae, and 30 semilandmarks were used to measure the curvature of the articulation surface of the prezygapophyses. For overall lumbar shape, PC1 explained 36.8% of the variance, and while a multiple linear regression of the log of centroid size compared to principal components 1-16 was not significant with a p>0.1, a bivariate regression of PC1 with log of centroid size shows that centroid size varies significantly with PC1 with a p<0.01. For shape of the articular surfaces, PC1 explained 77.2% of the variance, but no tested factors, including locomotor category, order, or size significantly correlated with the variation. Articular shape appears to correlate with lumbar stiffness, with animals such as the peccary, armadillo, and goat grouping together at the positive end of PC1 and otter, bobcat, and rabbit at the negative. P. ulta grouped with the stiff-backed species. Paradoxically, other features of P. ulta, such as its long body and tail, relatively short limbs, and plantigrade posture, are incongruent with other dorsostable mammals of comparable size in which stabilization is useful for jumping or running. The combination of short, flexible limbs and inflexible lumbar suggests P. ulta was an effective ambush predator but ineffective at covering large distances. Thus, a possible cause of extinction for P. ulta and the oxyaenids could be an inability to adapt to opening environments in the late Eocene and Oligocene
 
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