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University of Nebraska - Lincoln

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2020

Department of Earth and Atmospheric Sciences: Faculty Publications

Articles 1 - 21 of 21

Full-Text Articles in Physical Sciences and Mathematics

Estimating The Age And Mechanism Of Boulder Transport Related With Extreme Waves Using Lichenometry, Maria A. Oliveira, Esteve Llop, César Andrade, Cristina Branquinho, Ronald Goble, Sónia Queiroz, Maria C. Freitas, Pedro Pinho Dec 2020

Estimating The Age And Mechanism Of Boulder Transport Related With Extreme Waves Using Lichenometry, Maria A. Oliveira, Esteve Llop, César Andrade, Cristina Branquinho, Ronald Goble, Sónia Queiroz, Maria C. Freitas, Pedro Pinho

Department of Earth and Atmospheric Sciences: Faculty Publications

Tsunamis and storms cause considerable coastal flooding, numerous fatalities, destruction of structures, and erosion. The characterization of energy and frequency associated with each wave contribute to the risk assessment in coastal regions. Coastal boulder deposits represent a physical proof of extreme inundation and allow us to study the effects of marine floods further back in time than instrumental and historical records. Age estimation of these deposits is challenging due to lack of materials (such as sand, shells, corals, or organic matter) that retain information about the passage of time. Lichenometry, a simple age estimation method, which is cost effective, quick …

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Introduction To Special Section: Integrated Geophysical Imaging, Irina Filina, Rao Yalamanchili, Simone Re, Daniele Colombo, Antony Price, Vsevolod Egorov, Guimin Liu Nov 2020

Introduction To Special Section: Integrated Geophysical Imaging, Irina Filina, Rao Yalamanchili, Simone Re, Daniele Colombo, Antony Price, Vsevolod Egorov, Guimin Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

This special section illustrates the value of integration with nonseismic geophysical methods, namely potential fields (gravity and magnetics) and electric and electromagnetic techniques. The primary objective is to overcome the overall underappreciation of these methods as exploration tools. We provide their brief overview and present nine case studies illustrating how the integrative approach to geophysical data analysis influences the overall result and reduces the uncertainty of the derived solution.

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Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty Jul 2020

Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty

Department of Earth and Atmospheric Sciences: Faculty Publications

The widespread occurrence of lower Eocene chert and porcellanite has been viewed as a major paleoceanographic issue since the advent of ocean drilling, and both biotic and abiotic forcings have been proposed to explain it. We present a reconstruction of indurated siliceous sediment (ISS) and preserved biosiliceous sediment (PBS) occurrences in the Atlantic Ocean through the Paleocene and Eocene (~66 through 34 Ma). ISS and PBS distributions reveal dissimilar temporal trends, with the peak of ISS occurrences coinciding with the Early Eocene Climatic Optimum, in line with previous studies. PBS occurrences show a generally increasing trend culminating between 44 and …

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Late Cretaceous Stratigraphy And Paleoceanographic Evolution In The Great Australian Bight Basin Based On Results From Iodp Site U1512, K. G. Macleod, Lloyd T. White, Carmine C. Wainman, Mathieu Martinez, Matthew M. Jones, Sietske J. Batenburg, Laurent Riquier, Shannon J. Haynes, David K. Watkins, K. A. Bogus, H.-J. Brumsack, R. Do Monte Guerra, Kirsty M. Edgar, Trine Edvardsen, Dennis Harry, Takashi Hasegawa, R. W. Hobbs, Brian T. Huber, T. Jiang, J. Kuroda, E. Y. Lee, Yong-Xiang Li, Alessandro Maritatai, Lauren K. O'Connor, Maria Rose Petrizzo, Tracy M. Quan, C. Richter, Maria Luisa Garcia Tejada, G. Tagliaro, Erik Wolfgring, Zhaokai Xu Feb 2020

Late Cretaceous Stratigraphy And Paleoceanographic Evolution In The Great Australian Bight Basin Based On Results From Iodp Site U1512, K. G. Macleod, Lloyd T. White, Carmine C. Wainman, Mathieu Martinez, Matthew M. Jones, Sietske J. Batenburg, Laurent Riquier, Shannon J. Haynes, David K. Watkins, K. A. Bogus, H.-J. Brumsack, R. Do Monte Guerra, Kirsty M. Edgar, Trine Edvardsen, Dennis Harry, Takashi Hasegawa, R. W. Hobbs, Brian T. Huber, T. Jiang, J. Kuroda, E. Y. Lee, Yong-Xiang Li, Alessandro Maritatai, Lauren K. O'Connor, Maria Rose Petrizzo, Tracy M. Quan, C. Richter, Maria Luisa Garcia Tejada, G. Tagliaro, Erik Wolfgring, Zhaokai Xu

Department of Earth and Atmospheric Sciences: Faculty Publications

The Upper Cretaceous sedimentary sequence at International Ocean Discovery Program Site U1512 in the Ceduna Sub-basin of the Great Australian Bight represents a continuous, N 690 m thick interval of black silty clay and claystone spanning the lower Turonian through Lower Campanian (~10 million years). Sediments were deposited in an elongate, ~E-W oriented, ~2500 km long rift system that developed between Australia and Antarctica with an open-ocean connection to the west and a continental bridge to the east. Site U1512 cores provide a unique, continuous record of Late Cretaceous deposition in the Ceduna Sub-basin on the hanging wall of the …

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Evidence Of Ridge Propagation In The Eastern Gulf Of Mexico From Integrated Analysis Of Potential Fields And Seismic Data, Irina Filina, Mei Liu, Erin Beutel Jan 2020

Evidence Of Ridge Propagation In The Eastern Gulf Of Mexico From Integrated Analysis Of Potential Fields And Seismic Data, Irina Filina, Mei Liu, Erin Beutel

Department of Earth and Atmospheric Sciences: Faculty Publications

Integrated analysis of gravity, magnetic, and seismic data reveals two phases of spreading in the eastern Gulf of Mexico (GOM) including two distinct spreading centers, suggesting a major ridge reorganization during the opening of the eastern part of the GOM. Ridge propagation between the two spreading episodes explains the following observations: (1) the drastic asymmetry in the oceanic domain of northeastern GOM, (2) the presence of two distinct crustal zones with dramatically different thickness and physical properties, and (3) the observed seismicity within the oceanic domain that is not aligned with any known tectonic structure. The initial Late Jurassic spreading …

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Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz Jan 2020

Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

An ecosystem’s ability to maintain structure and function following disturbance, defined as resilience, is influenced by a hierarchy of environmental controls, including climate, surface cover, and ecological relationships that shape biological community composition and productivity. This study examined lacustrine sediment records of naturally fishless lakes in Yellowstone National Park to reconstruct the response of aquatic communities to climate and trophic cascades from fish stocking. Sediment records of diatom algae did not exhibit a distinct response to fish stocking in terms of assemblage or algal productivity. Instead, 3 of 4 lakes underwent a shift to dominance by benthic diatom species from …

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Mod$$At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan Suter, Prasanna Gowda Jan 2020

Mod$$At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan Suter, Prasanna Gowda

Department of Earth and Atmospheric Sciences: Faculty Publications

In this paper, we introduce a hydro-economic modeling framework for the management of groundwater re- sources that are used for irrigated agricultural production. The model, MOD$$AT, can be used to study the costs of aquifer depletion and the net benefits of specific aquifer management policies. MOD$$AT is composed of three components, namely, an economic component, a hydrologic component and an agronomic component. A main goal of this paper is to introduce the hydro-economic model and describe how it can be transferable to different contexts. With this objective in mind, we describe model components step-by-step so that the process of integration …

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Data Generated During The 2018 Lapse-Rate Campaign: An Introduction And Overview, Gijs De Boer, Adam Houston, Et Al. Jan 2020

Data Generated During The 2018 Lapse-Rate Campaign: An Introduction And Overview, Gijs De Boer, Adam Houston, Et Al.

Department of Earth and Atmospheric Sciences: Faculty Publications

Unmanned aircraft systems (UASs) offer innovative capabilities for providing new perspectives on the atmosphere, and therefore atmospheric scientists are rapidly expanding their use, particularly for studying the planetary boundary layer. In support of this expansion, from 14 to 20 July 2018 the International Society for Atmospheric Research using Remotely piloted Aircraft (ISARRA) hosted a community flight week, dubbed the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE- RATE; de Boer et al., 2020a). This field campaign spanned a 1-week deployment to Colorado’s San Luis Valley, involving over 100 students, scientists, engineers, pilots, and outreach coordinators. …

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Mid‐Holocene Grounding Line Retreat And Readvance At Whillans Ice Stream, West Antarctica, R. A. Venturelli, M. R. Siegfried, K. A. Roush, W. Li, J. Burnett, Robert Zook, H. A. Fricker, J. C. Priscu, A. Leventer, B. E. Rosenheim Jan 2020

Mid‐Holocene Grounding Line Retreat And Readvance At Whillans Ice Stream, West Antarctica, R. A. Venturelli, M. R. Siegfried, K. A. Roush, W. Li, J. Burnett, Robert Zook, H. A. Fricker, J. C. Priscu, A. Leventer, B. E. Rosenheim

Department of Earth and Atmospheric Sciences: Faculty Publications

Understanding ice sheet evolution through the geologic past can help constrain ice sheet models that predict future ice dynamics. Existing geological records of grounding line retreat in the Ross Sea, Antarctica, have been confined to ice‐free and terrestrial archives, which reflect dynamics from periods of more extensive ice cover. Therefore, our perspective of grounding line retreat since the Last Glacial Maximum remains incomplete. Sediments beneath Ross Ice Shelf and grounded ice offer complementary insight into the southernmost extent of grounding line retreat, yielding a more complete view of ice dynamics during deglaciation. Here we thermochemically separate the youngest organic carbon …

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The Influence Of Isolated Thunderstorms And The Low-Level Wind Field On Nocturnally Migrating Birds In Central North America, Matthew V.D. Broeke, Timothy J. Gunkel Jan 2020

The Influence Of Isolated Thunderstorms And The Low-Level Wind Field On Nocturnally Migrating Birds In Central North America, Matthew V.D. Broeke, Timothy J. Gunkel

Department of Earth and Atmospheric Sciences: Faculty Publications

Seasonal bird migration occurs on large spatial scales and is influenced by many factors including weather conditions. Weather can include thunderstorms, which may force migrants to land or cause them to reroute a migration path. In this study, a sample of isolated thunderstorms was analyzed from the domains of three weather radars in the central United States to test hypotheses regarding the influence of thunderstorms on the distribution of migrants. Migrating bird density was often reduced in the wake of storms, and this wake reduction was typically more pronounced for larger, more intense and faster- moving storms, particularly in eastern …

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Diagnostic Analysis Of Bank Storage Effects On Sloping Floodplains, Xiuyu Liang, Vitaly Zlotnik, You‐Kuan Zhang, Pei Xin Jan 2020

Diagnostic Analysis Of Bank Storage Effects On Sloping Floodplains, Xiuyu Liang, Vitaly Zlotnik, You‐Kuan Zhang, Pei Xin

Department of Earth and Atmospheric Sciences: Faculty Publications

Stream bank storage effects during floods have received limited attention, despite the significant role of such floods in aquifer water budgets. One reason is the complexity of geometry of the problem, which commonly has been treated numerically. Using a simple model in a domain with moving boundary, a semianalytical solution for bank storage effects is proposed to account for stream stage hydrograph, floodplain slope, and aquifer parameters. The results extend classic solutions by Cooper and Rorabaugh (1963, https://doi.org/10.3133/wsp1536J) for idealized vertical streambanks but applied to realistic floodplain cross sections. The accuracy of the semianalytical solution is verified by a one‐dimensional …

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Surficial Fractures In The Navajo Sandstone, South-Western Usa: The Roles Of Thermal Cycles, Rainstorms, Granular Disintegration, And Iterative Cracking, David Loope, Garrison R. Loope, Caroline M. Burberry, Clinton Rowe, Gerald C. Bryant Jan 2020

Surficial Fractures In The Navajo Sandstone, South-Western Usa: The Roles Of Thermal Cycles, Rainstorms, Granular Disintegration, And Iterative Cracking, David Loope, Garrison R. Loope, Caroline M. Burberry, Clinton Rowe, Gerald C. Bryant

Department of Earth and Atmospheric Sciences: Faculty Publications

Deep (> 5 m) sheeting fractures in the Navajo sandstone are evident at numerous sites in southern Utah and derive from tectonic stresses. Strong diurnal thermal cycles are, however, the likely triggers for shallow (< 0.3 m) sheeting fractures. Data from subsurface thermal sensors reveal that large temperature differences between sensors at 2 and 15 cm depth on clear summer afternoons are as great as those that trigger sheeting fractures in exposed California granite. Extensive polygonal patterns in the Navajo sandstone are composed of surface-perpendicular fractures and were produced by contractile stresses. Numerous studies have shown that porewater diminishes the tensile strength of sandstone. Based on our thermal records, we propose that cooling during monsoonal rainstorms triggers polygonal fracturing of temporarily weakened rock. On steep outcrops, polygonal patterns are rectilinear and orthogonal, with T-vertices. Lower-angle slopes host hexagonal patterns (defined by the dominance of Y-vertices). Intermediate patterns with rectangles and hexagons of similar scale are common. We posit that outcropping fractures are advancing downward by iterative steps, and that hexagons on sandstone surfaces (like prismatic columns of basalt) have evolved from ancestral orthogonal polygons of similar scale. In lava flows, fractures elongate intermittently as they follow a steep thermal gradient (the source of stress) as it rapidly moves through the rock mass. In our model, a steep, surficial thermal gradient descends through unfractured sandstone, but at the slow pace of granular disintegration. Through time, as the friable rock on stable slopes erodes, iterative cracking advances into new space. Hexagonal patterns form as new fractures, imperfectly guided by the older ones, propagate in new directions, and vertices drift into a configuration that minimizes the ratio of fracture length to polygon area.

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Assessing Agricultural Risk Management Using Historic Crop Insurance Loss Data Over The Ogallala Aquifer, Julian Reyes, Emile Elias, Erin M.K. Haacker, Amy Kremen, Lauren Parker, Caitlin Rottler Jan 2020

Assessing Agricultural Risk Management Using Historic Crop Insurance Loss Data Over The Ogallala Aquifer, Julian Reyes, Emile Elias, Erin M.K. Haacker, Amy Kremen, Lauren Parker, Caitlin Rottler

Department of Earth and Atmospheric Sciences: Faculty Publications

Much of the agricultural production in the Ogallala Aquifer region relies on groundwater for irrigation. In addition to declining water levels, weather and climate-driven events affect crop yields and revenues. Crop insurance serves as a risk management tool to mitigate these perils. Here, we seek to understand what long-term crop insurance loss data can tell us about agricultural risk management in the Ogallala. We assess patterns and trends in crop insurance loss data from the U.S. Department of Agriculture Risk Management Agency. Indemnities, or insurance payments, totaled $22 billion from 1989–2017 for the 161 counties that overlie the Ogallala Aquifer. …

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Diversity And Equality In Honours And Awards Programs – Steps Towards A Fair Representation Of Membership, Mary Anne Holmes, Latoya Myles, Blair Schneider Jan 2020

Diversity And Equality In Honours And Awards Programs – Steps Towards A Fair Representation Of Membership, Mary Anne Holmes, Latoya Myles, Blair Schneider

Department of Earth and Atmospheric Sciences: Faculty Publications

Honours and awards bestowed by professional societies recognize and reward members who have advanced the goals and values of that society. All too often, however, awards reflect a small network of people who know about the awards and participate in the process. This network works wonderfully for the people lucky enough to be in it, but typically neglects the full range and breadth of scholarship and service within the society. We represent a combined 15C years’ experience on the honours’ committee for a large professional society (the American Geophysical Union) and here offer strategies to increase the representation of honourees.Women …

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At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions☆, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan F. Suter, Prasanna Gowda Jan 2020

At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions☆, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan F. Suter, Prasanna Gowda

Department of Earth and Atmospheric Sciences: Faculty Publications

In this paper, we introduce a hydro-economic modeling framework for the management of groundwater resources that are used for irrigated agricultural production. The model, MOD$$AT, can be used to study the costs of aquifer depletion and the net benefits of specific aquifer management policies. MOD$$AT is composed of three components, namely, an economic component, a hydrologic component and an agronomic component. A main goal of this paper is to introduce the hydro-economic model and describe how it can be transferable to different contexts. With this objective in mind, we describe model components step-by-step so that the process of integration can …

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Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz Jan 2020

Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

High-elevation tropical lakes are excellent sentinels of global change impacts, such as climate warming, land-use change, and atmospheric deposition. These effects are often correlated with temporal and spatial beta diversity patterns, with some local communities contributing more than others, a phenomenon known as local contribution to beta diversity (LCBD) or ecological uniqueness. Microorganisms, such as diatoms, are considered whole-ecosystem indicators, but little is known about their sensitivity and specificity in beta diversity studies mostly because of the lack of large spatial and temporal datasets. To fill this gap, we used a tropical South American diatom database comprising modern (144 lakes) …

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Disdrometer, Polarimetric Radar, And Condensation Nuclei Observations Of Supercell And Multicell Storms On 11 June 2018 In Eastern Nebraska, Matthew S. Van Den Broeke Jan 2020

Disdrometer, Polarimetric Radar, And Condensation Nuclei Observations Of Supercell And Multicell Storms On 11 June 2018 In Eastern Nebraska, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Disdrometer and condensation nuclei (CN) data are compared with operational polarimetric radar data for one multicell and one supercell storm in eastern Nebraska on 11 June 2018. The radar was located ~14.3 km from the instrumentation location and provided excellent observation time series with new low-level samples every 1–2 min. Reflectivity derived by the disdrometer and radar compared well, especially in regions with high number concentration of drops and reflectivity <45 dBZ. Differential reflectivity also compared well between the datasets, though it was most similar in the supercell storm. Rain rate calculated by the disdrometer closely matched values estimated by the radar when reflectivity and differential reflectivity were used to produce the estimate. Concentration of CN generally followed precipitation intensity for the leading convective cell, with evidence for higher particle concentration on the edges of the convective cell associated with outflow. The distribution of CN in the supercell was more complex and generally did not follow precipitation intensity.

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The Influence Of Isolated Thunderstorms And The Low-Level Wind Field On Nocturnally Migrating Birds In Central North America, Matthew S. Van Den Broeke, Timothy J. Gunkel Jan 2020

The Influence Of Isolated Thunderstorms And The Low-Level Wind Field On Nocturnally Migrating Birds In Central North America, Matthew S. Van Den Broeke, Timothy J. Gunkel

Department of Earth and Atmospheric Sciences: Faculty Publications

Seasonal bird migration occurs on large spatial scales and is influenced by many factors including weather conditions. Weather can include thunderstorms, which may force migrants to land or cause them to reroute a migration path. In this study, a sample of isolated thunderstorms was analyzed from the domains of three weather radars in the central United States to test hypotheses regarding the influence of thunderstorms on the distribution of migrants. Migrating bird density was often reduced in the wake of storms, and this wake reduction was typically more pronounced for larger, more intense and faster- moving storms, particularly in eastern …

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A Model Of Icewedge Polygon Drainage In Changing Arctic Terrain, Vitaly Zlotnik, Dylan R. Harp, Elchin E. Jafarov, Charles J. Abolt Jan 2020

A Model Of Icewedge Polygon Drainage In Changing Arctic Terrain, Vitaly Zlotnik, Dylan R. Harp, Elchin E. Jafarov, Charles J. Abolt

Department of Earth and Atmospheric Sciences: Faculty Publications

As ice wedge degradation and the inundation of polygonal troughs become increasingly common processes across the Arctic, lateral export of water from polygonal soils may represent an important mechanism for the mobilization of dissolved organic carbon and other solutes. However, drainage from ice wedge polygons is poorly understood. We constructed a model which uses cross-sectional flow nets to define flow paths of meltwater through the active layer of an inundated low-centered polygon towards the trough. The model includes the eects of evaporation and simulates the depletion of ponded water in the polygon center during the thaw season. In most simulations, …

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Controls On Channel Deposits Of Highly Variable Rivers: Comparing Hydrology And Event Deposits In The Burdekin River, Australia, Jan Alexander, Christopher M. Herbert, Christopher R. Fielding, Kathryn J. Amos Jan 2020

Controls On Channel Deposits Of Highly Variable Rivers: Comparing Hydrology And Event Deposits In The Burdekin River, Australia, Jan Alexander, Christopher M. Herbert, Christopher R. Fielding, Kathryn J. Amos

Department of Earth and Atmospheric Sciences: Faculty Publications

Discharge event frequency, magnitude and duration all control river chan- nel morphology and sedimentary architecture. Uncertainty persists as to whether alluvial deposits in the rock record are a time-averaged amalgam from all discharge events, or a biased record of larger events. This paper investigates the controls on channel deposit character and subsurface strati- graphic architecture in a river with seasonal discharge and very high inter- annual variability, the Burdekin River of north-east Australia. In such rivers, most sediment movement is restricted to a few days each year and at other times little sediment moves. However, the maximum discharge magnitude does …

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End-Permian (252 Mya) Deforestation, Wildfires And Flooding—An Ancient Biotic Crisis With Lessons For The Present, Vivi Vajda, Stephen Mcloughlin, Chris Mays, Tracy D. Frank, Christopher R. Fielding, Allen Tevyaw, Veiko Lehsten, Malcolm Bocking, Robert S. Nicoll Jan 2020

End-Permian (252 Mya) Deforestation, Wildfires And Flooding—An Ancient Biotic Crisis With Lessons For The Present, Vivi Vajda, Stephen Mcloughlin, Chris Mays, Tracy D. Frank, Christopher R. Fielding, Allen Tevyaw, Veiko Lehsten, Malcolm Bocking, Robert S. Nicoll

Department of Earth and Atmospheric Sciences: Faculty Publications

Current large-scale deforestation poses a threat to ecosystems globally, and imposes substantial and prolonged changes on the hydrological and carbon cycles. The tropical forests of the Amazon and Indonesia are currently undergoing deforestation with catastrophic ecological consequences but widespread deforestation events have occurred several times in Earth’s history and these provide lessons for the future. The end-Permian mass-extinction event (EPE; ∼252 Ma) provides a global, deep-time analogue for modern deforestation and diversity loss. We undertook centimeter-resolution palynological, sedimentological, carbon stable-isotope and paleobotanical investigations of strata spanning the end- Permian event at the Frazer Beach and Snapper Point localities, in the …

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