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Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker 2016 University of New Hampshire, Durham

Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

Xiaoyang Zhang

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the ...


High-Resolution Signatures Of Oxygenation And Microbiological Activity In Speleothem Fluid Inclusions, Nigel Blamey, Penelope J. Boston, Laura Rosales-Lagarde 2016 New Mexico Institute of Mining and Technology

High-Resolution Signatures Of Oxygenation And Microbiological Activity In Speleothem Fluid Inclusions, Nigel Blamey, Penelope J. Boston, Laura Rosales-Lagarde

International Journal of Speleology

Speleothems frequently host “fossil” fluids that were trapped in small inclusions during growth. Such fluids may provide valuable clues to past microbial, geochemical, and climatic processes during their formation. However, one difficulty is to understand which gases represent background atmosphere and fluids within a given cave system at a particular time, and which may be the product of post-trapping residual microbial activity or abiotic chemical reactions? Do we have any hope of sorting out these differences? The success depends on a quantitative understanding of the gas composition trapped in the inclusions and an understanding of the interactions of cave mineralogy ...


Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll 2016 University of Tennessee, Knoxville

Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll

Masters Theses

This study tested whether transport distances (< 500 m) have the capacity to shape the geochemistry of sediments across multiple grain-size populations due to sorting derived from a single source. In the Stepladder Mountains, Mojave Desert, CA, a < 1 km2 [square kilometers] watershed allows for a controlled study to understand how modern sediments acquire their composition from a single granodioritic source in an arid climate where there is no chemical weathering. Sediments are naturally sorted into distinct grain-size populations, with modes ranging from very fine sand to gravel within a single, alluvial channel. Sediment samples representative of each population were petrographically and geochemically analyzed in order to test the effectiveness of commonly used discrimination diagrams. Sediments became proportionally enriched in plagioclase and biotite and depleted in K-feldspar and quartz with decreasing grain size ...


Water-Rock Interactions And Seasonal Hydrologic Processes In Constructed Everglades Tree Islands, Andres E. Prieto Estrada 2016 Florida International University

Water-Rock Interactions And Seasonal Hydrologic Processes In Constructed Everglades Tree Islands, Andres E. Prieto Estrada

FIU Electronic Theses and Dissertations

The decline of tree islands in the freshwater-Everglades wetland because of hydrologic manipulation, has compromised valuable ecosystem services. Although the role of tree islands in maintaining freshwater quality stems largely from evapotranspiration processes, fundamental questions remain about the effects of different geologic materials on their hydrogeochemical functioning. To reduce this uncertainty, the lithological composition of a set of man-made tree islands was investigated coupled with long-term hydrologic and hydrochemical data. Key results indicate that limestone substrates and peat substrates with elevated proportions of sand, facilitated surface water-groundwater interactions and mineral dissolution. However, limestone-based islands were more effective in lowering the ...


Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher 2016 Southern Cross University

Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher

Adjunct Professor Richard T Bush

No abstract provided.


Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher 2016 Southern Cross University

Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher

Dr Nicholas J Ward

No abstract provided.


Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher 2016 Southern Cross University

Lower Lakes Carbon Project: The Aquatic Vegetation Contribution To Carbon Pools, Leigh A. Sullivan, Nicholas J. Ward, Richard T. Bush, Alicia Hidden, Diane M. Fyfe, Michelle Bush, Crystal A. Maher

Adjunct Professor Leigh A Sullivan

No abstract provided.


The Role Of Diagenesis In Reservoir Development Of The Big Clifty (Jackson) Sandstone In South-Central Kentucky, Kort H. Butler 2016 Western Kentucky University

The Role Of Diagenesis In Reservoir Development Of The Big Clifty (Jackson) Sandstone In South-Central Kentucky, Kort H. Butler

Masters Theses & Specialist Projects

The Big Clifty is a Chesterian-age Mississippian sandstone member of the Golconda Formation that extends from south-central Kentucky into adjacent Illinois and Indiana. Asphaltic deposits and conventional petroleum plays are distributed along the Pennyrile Fault System and Plateau in the southeastern portion of the Illinois basin. In south-central Kentucky anomalous oil-saturation geometries are observed in cored sections of the Big Clifty from wells in Warren and Butler counties along the margin of the Pennyrile Plateau. Petrographic study of the cores has revealed several diagenetic processes that have contributed to, or are directly responsible for, the anomalous oil saturation geometries and ...


Proportions Of Convective And Stratiform Precipitation Revealed In Water Isotope Ratios, Pradeep K. Aggarwal, Ulrike Romatschke, Luis Araguas-Araguas, Dagnachew Belachew, Fred J. Longstaffe, Peter Berg, Courtney Schumacher, Aaron Funk 2016 International Atomic Energy Agency

Proportions Of Convective And Stratiform Precipitation Revealed In Water Isotope Ratios, Pradeep K. Aggarwal, Ulrike Romatschke, Luis Araguas-Araguas, Dagnachew Belachew, Fred J. Longstaffe, Peter Berg, Courtney Schumacher, Aaron Funk

Earth Sciences Publications

Tropical and midlatitude precipitation is fundamentally of two types, spatially-limited and high-intensity convective or widespread and lower-intensity stratiform, owing to differences in vertical air motions and microphysical processes governing rain formation. These processes are difficult to observe or model and precipitation partitioning into rain types is critical for understanding how the water cycle responds to climate changes. Here, we combine two independent data sets – convective and stratiform precipitation fractions, derived from the Tropical Rainfall Measuring Mission satellite or synoptic cloud observations, and stable isotope and tritium compositions of surface precipitation, derived from a global network – to show that isotope ratios ...


Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey 2016 California Polytechnic State University, San Luis Obispo

Structure And Geochronology Of The White Fork Pluton, Southern Sierra Nevada, Ian Richard Mahaffey

Natural Resources Management and Environmental Sciences

The Sierra Nevada batholith represents an archetypal continental arc, although the style of deformation throughout the history of the arc is only poorly understood, in part due to the voluminous nature of Late Cretaceous magmatism that has overprinted earlier structures. The purpose of this study is to gain a better understanding of pre-Late Cretaceous deformation in the Sierra Nevada batholith through a structural and geochronological study of the Jurassic White Fork pluton. A Jurassic age for the White Fork pluton is indicated by its inclusion of numerous 148 Ma Independence dikes, and geochronology on the White Fork pluton is limited ...


Inter- And Intra-Annual C And N Isotopic Variability Of C3 And C4 Grasses In A Temperate-Humid Dune Environment, Roshni R. Patel 2016 The University of Western Ontario

Inter- And Intra-Annual C And N Isotopic Variability Of C3 And C4 Grasses In A Temperate-Humid Dune Environment, Roshni R. Patel

Electronic Thesis and Dissertation Repository

Seasonal and annual variations in foliar δ13C and δ15N of a C3 grass Ammophila breviligulata and a C4 grass Calamovilfa longifolia from the sand dunes of Pinery Provincial Park in southern Ontario, Canada were investigated to assess isotopic variability at a single site within a temperate-humid climatic zone. This work quantifies seasonal δ13C and δ15N variation, tests for correlation of δ13C and δ15N with weather parameters, and evaluates the isotopic responses of these grasses to location within the dune system. Throughout the 2014 growing season, there ...


Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres 2016 Stephen F Austin State University

Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres

Electronic Theses and Dissertations

Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that ...


An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner 2016 Stephen F Austin State University

An Investigation Of Hydrogeologic, Stratigraphic, And Structural Controls On Acer Grandidentatum Communities In A Karst Landscape, Owl Mountain Province, Fort Hood Military Installation, Texas, Melinda S. Faulkner

Electronic Theses and Dissertations

The Owl Mountain Province is located within the Fort Hood Military Installation, an approximately 880 km2 installation established in the 1940s in Bell and Coryell counties, Texas, which has undergone extensive land use changes associated with military training, maintaining much of the vegetation in early succession. This study investigates thelithologic, stratigraphic, and structural controls on the hydrologic, hydrogeologic, and geomorphologic evolution of the Owl Mountain Province as expressed by mesic vegetation communities, including Pleistocene relicts Acer grandidentatum, within karst terrains. These systems exhibit complexly overprinted speleogenetic evolutions within a dynamic groundwater regime resulting from regional climate shifts throughout the Neogene ...


The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson 2016 Stephen F. Austin State University

The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson

Electronic Theses and Dissertations

The stratigraphy of the Pojoaque Member of the Tesuque Formation near Española, NM is not well understood. This region, during the Middle Miocene, represented a dynamic alluvial fan-fluvial-lacustrine environment within the Española Basin while the Rio Grande Rift was active. Cavazza (1986) identified two paleodrainage systems (lithosome A, basin-margin facies and B, basin-floor facies) by means of sandstone and conglomerate petrology, paleocurrent, and sedimentary facies analyses. After x-ray diffraction analyses of claystones within lithosome B, mordenite was discovered, which is a zeolite mineral commonly found within volcanic rocks. This is significant because the presence of mordenite confirms Cavazza’s (1986 ...


Characterizing The Earliest Stages Of Partial Melting: A Study Of The Pyrometamorphic Aureole Of Miocene Mt. Perkins Pluton, Northwest Arizona, Mathew Beshears 2016 University of Nevada, Las Vegas

Characterizing The Earliest Stages Of Partial Melting: A Study Of The Pyrometamorphic Aureole Of Miocene Mt. Perkins Pluton, Northwest Arizona, Mathew Beshears

UNLV Theses, Dissertations, Professional Papers, and Capstones

Partial melting is an important process in the evolution of continental crust. Due to its progressive nature, evidence of the early stages of partial melting is often overprinted by later, advanced stages of partial melting. Experimental work has provided a model for the early stages of partial melting, but is limited to timescales of hours to weeks. Pyrometamorphic environments within the contact aureole of mafic intrusions provide natural laboratories for the study of the earliest stages of partial melt production on geologic time scales of 102 collected along two traverses of the tilted pyrometamorphic aureole of the Mt. Perkins pluton ...


Evaluation Of Groundwater Quality In Paleozoic Aquifers Using Gis Techniques, Central Texas, Garrett R. Harris 2016 Stephen F Austin State University

Evaluation Of Groundwater Quality In Paleozoic Aquifers Using Gis Techniques, Central Texas, Garrett R. Harris

Electronic Theses and Dissertations

Lab analyses of groundwater chemistry from monitoring wells completed in the Paleozoic Aquifers surrounding the Llano Uplift of Central Texas has been recorded and made available to the public through the Texas Water Development Board (TWDB). This study evaluated the results of these data dating back to the 1940s to determine changes over time, the dynamics of the hydrologic system, and the locations where hydraulic connectivity is most probable. The initial results established two distinct hydrologic systems that required the separation of the northern from the southern region. The northern sub-region (NSR) contains the largest expanse of continuity of both ...


The Petrology And Geochemistry Of The Independence Dike Swarm, Owen’S Valley, California, Sean B. O'Donnell 2016 Cedarville University

The Petrology And Geochemistry Of The Independence Dike Swarm, Owen’S Valley, California, Sean B. O'Donnell

The Research and Scholarship Symposium

Petrologic studies are important because they provide insights into the conditions under which rocks form. The Late Jurassic Independence Dike Swarm is a series of vertical igneous dikes that crop out in eastern and southern California, and range from mafic to felsic in composition. In order to examine their petrology and geochemistry, surface samples were collected from four different dike outcrops within Owen’s Valley, CA. The samples were examined through thin-section analysis under a petrographic microscope, X-ray diffraction analysis, and X-ray fluorescence analysis. Mineral composition, mineral size, major, trace, and rare earth element concentrations were collected from these analyses ...


Reconstructing Paleoenvironmental Conditions From Hydrothermally Altered Lacustrine Sediments From Hspdp West Turkana-Kaitio Core Material Via Coupled Mineralogical And Geochemical Analysis, Mamta Sanam Chaudhary 2016 Georgia State University

Reconstructing Paleoenvironmental Conditions From Hydrothermally Altered Lacustrine Sediments From Hspdp West Turkana-Kaitio Core Material Via Coupled Mineralogical And Geochemical Analysis, Mamta Sanam Chaudhary

Georgia State Undergraduate Research Conference

No abstract provided.


A Mineralogical And Geochemical Analysis Of Bed I In Olduvai Gorge, Tanzania, David Michael Davis, Sanam M. Chaudhary, Alex M. Simpson, Daniel M. Deocampo, Nathan M. Rabideaux, Gail Ashley, Kevin Garrett 2016 Georgia State University

A Mineralogical And Geochemical Analysis Of Bed I In Olduvai Gorge, Tanzania, David Michael Davis, Sanam M. Chaudhary, Alex M. Simpson, Daniel M. Deocampo, Nathan M. Rabideaux, Gail Ashley, Kevin Garrett

Georgia State Undergraduate Research Conference

No abstract provided.


Evidence For Shallow Saltwater Intrusion: Wormsloe State Historic Site, Chatham County, Georgia, Chelsea E. Bush, Lori A. Farley, Tim J. Herold 2016 Georgia State University

Evidence For Shallow Saltwater Intrusion: Wormsloe State Historic Site, Chatham County, Georgia, Chelsea E. Bush, Lori A. Farley, Tim J. Herold

Georgia State Undergraduate Research Conference

No abstract provided.


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