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Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor 2010 Wesleyan University

Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor

Division III Faculty Publications

Differential compaction associated with prograding and aggrading steep-rimmed carbonate margins leads to penecontemporaneous and post- depositional modifications of stratal geometries and tensile and shear stress concentrations that result in brittle deformation. In an effort to investigate controls on these deformation processes, we employ a step-wise gravity loaded elastic model that captures pre-failure displacement and stress field patterns for a depositional geometry based on the Permian Capitan depositional system, Guadalupe Mountains, West Texas and New Mexico, USA. We consider four model geometries with varying progradation to aggradation (P/A) ratio, from strongly prograding (P/A=10) to strongly aggrading (P/A ...


Simulating Dioxane Transport In A Heterogeneous Glacial Aquifer System (Washtenaw County, Michigan) Using Publicly Available Models And Data, Rungroj Benjakul 2010 Michigan Technological University

Simulating Dioxane Transport In A Heterogeneous Glacial Aquifer System (Washtenaw County, Michigan) Using Publicly Available Models And Data, Rungroj Benjakul

Dissertations, Master's Theses and Master's Reports - Open

The primary challenge in groundwater and contaminant transport modeling is obtaining the data needed for constructing, calibrating and testing the models. Large amounts of data are necessary for describing the hydrostratigraphy in areas with complex geology. Increasingly states are making spatial data available that can be used for input to groundwater flow models. The appropriateness of this data for large-scale flow systems has not been tested. This study focuses on modeling a plume of 1,4-dioxane in a heterogeneous aquifer system in Scio Township, Washtenaw County, Michigan. The analysis consisted of: (1) characterization of hydrogeology of the area and construction ...


Differential Gps As A Monitoring Tool On Volcano Santa Ana (Illamatepec) And The Coatepeque Caldera, El Salvador, Hans N. Lechner 2010 Michigan Technological University

Differential Gps As A Monitoring Tool On Volcano Santa Ana (Illamatepec) And The Coatepeque Caldera, El Salvador, Hans N. Lechner

Dissertations, Master's Theses and Master's Reports - Open

We used differential GPS measurements from a 13 station GPS network spanning the Santa Ana Volcano and Coatepeque Caldera to characterize the inter-eruptive activity and tectonic movements near these two active and potentially hazardous features. Caldera-forming events occurred from 70-40 ka and at Santa Ana/Izalco volcanoes eruptive activity occurred as recently as 2005. Twelve differential stations were surveyed for 1 to 2 hours on a monthly basis from February through September 2009 and tied to a centrally located continuous GPS station, which serves as the reference site for this volcanic network. Repeatabilities of the averages from 20-minute sessions taken ...


Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven 2010 Michigan Technological University

Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven

Dissertations, Master's Theses and Master's Reports - Open

We hypothesized that the spatial distribution of groundwater inflows through river bottom sediments is a critical factor associated with the selection of coaster brook trout (a life history variant of Salvelinus fontinalis,) spawning sites. An 80-m reach of the Salmon Trout River, in the Huron Mountains of the upper peninsula of Michigan, was selected to test the hypothesis based on long-term documentation of coaster brook trout spawning at this site. Throughout this site, the river is relatively similar along its length with regard to stream channel and substrate features. A monitoring well system consisting of an array of 27 wells ...


The Presidential Range: Its Geologic And Tectonic History, J. Dykstra Eusden 2010 Bates College

The Presidential Range: Its Geologic And Tectonic History, J. Dykstra Eusden

Faculty Books

The complete hiker’s guide and map to the bedrock geology of the Presidential Range, New Hampshire —

This guide and its accompanying geologic map describe the bedrock geology and plate tectonic history of the Presidential Range, the highest peaks in the northeastern United States. The color illustrations and writing style make this accessible to all enthusiasts of the mountains. The map (21.5 x 28) shows the bedrock geology and highlights locations where hikers may view key exposures of bedrock in the field.


Analysis Of Fluvial Suspended Sediment Load Contribution Through Anthropocene History To The South Atlantic Bight Coastal Zone, U.S.A., K McCarney-Castle, George Voulgaris, A J. Kettner 2010 University of South Carolina - Columbia

Analysis Of Fluvial Suspended Sediment Load Contribution Through Anthropocene History To The South Atlantic Bight Coastal Zone, U.S.A., K Mccarney-Castle, George Voulgaris, A J. Kettner

Faculty Publications

Discerning the effects of anthropogenic activities (i.e., reservoir construction, land use change), as opposed to those of natural processes (i.e., climate variability), on suspended sediment flux has become an increasingly difficult challenge. This contribution presents water and suspended sediment flux from five major watersheds that discharge into the southeastern U.S. Atlantic, a region that is currently considered sediment starved. Three periods of Anthropocenetime were defined and evaluated: (1) “pre-European conditions” (1680–1700), (2) “pre-dam conditions" (1905-1925), and (3) "post-dam conditions" (1985-2005). Physical and hydrologic watershed data were used to run a climate-driven hydrological transport numerical model (HydroTrend ...


Comparison Of Carbon Stocks & Importance Values In Correlation With Past Land Use In The Gordon Natural Area, Timothy Hoffer, Steffen Lubbe 2010 West Chester University of Pennsylvania

Comparison Of Carbon Stocks & Importance Values In Correlation With Past Land Use In The Gordon Natural Area, Timothy Hoffer, Steffen Lubbe

Forest Carbon Storage Study Documents

No abstract provided.


Ordway Weather And Water Data 2010, Macalester College 2010 Macalester College

Ordway Weather And Water Data 2010, Macalester College

Ordway Weather Data

Contains daily readings for the year indicated. The values include: PAR umol/s/m2, avg wind dir degree, avg windspeed mph, Avg Max Windspeed mph, Avg airtemp C, Avg RH %, Avg BP mmHg, Avg DailyRain in, Avg Rain Duration sec, Avg RainIntensity in/h, Avg Water Temp F, Avg sp cond mS/cm, avg pH, Avg Turb NTU+, Avg ODOSat %, Avg ODO mg/L, Water station PAR umol/s/m2, Avg Water Level m. File format: CSV.


An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. McFarlane, Charles Brewer-Carias 2010 Carleton University

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation ...


A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. McFarlane, Martin Sabol, Joyce Lundberg 2010 Claremont McKenna College; Pitzer College; Scripps College

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from ...


Re-Interpreting Great Lakes Shorelines As Components Of Wave-Influenced Deltas: An Example From The Portage River, Lake Erie, Ohio, James E. Evans 2010 Bowling Green State University - Main Campus

Re-Interpreting Great Lakes Shorelines As Components Of Wave-Influenced Deltas: An Example From The Portage River, Lake Erie, Ohio, James E. Evans

James E. Evans

No abstract provided.


Survival And Growth Responses Of Eight Everglades Tree Species Along An Experimental Hydrological Gradient On Two Tree Island Types, Susana L. Stoffella, Michael S. Ross, Jay P. Sah, René M. Price, Pamela L. Sullivan, Eric A. Cline, Leonard J. Scinto 2010 Southeast Environmental Research Center, Florida International University

Survival And Growth Responses Of Eight Everglades Tree Species Along An Experimental Hydrological Gradient On Two Tree Island Types, Susana L. Stoffella, Michael S. Ross, Jay P. Sah, René M. Price, Pamela L. Sullivan, Eric A. Cline, Leonard J. Scinto

FCE LTER Journal Articles

Questions: How are the early survival and growth of seedlings of Everglades tree species planted in an experimental setting on artificial tree islands affected by hydrology and substrate type? What are the implications of these responses for broader tree island restoration efforts?

Location: Loxahatchee Impoundment Landscape Assessment (LILA), Boynton Beach, Florida, USA.

Methods: An experiment was designed to test hydrological and substrate effects on seedling growth and survivorship. Two islands – a peat and a limestone-core island representing two major types found in the Everglades – were constructed in four macrocosms. A mixture of eight tree species was planted on each island ...


Everglades Ridge, Slough, And Tree Island Mosaics: Year 2 Annual Report, Michael S. Ross, James B. Heffernan, Jay P. Sah, Pablo L. Ruiz, Adam A. Spitzig, Ewan Isherwood 2010 Southeast Environmental Research Center & Department of Earth and Environment, Florida International University

Everglades Ridge, Slough, And Tree Island Mosaics: Year 2 Annual Report, Michael S. Ross, James B. Heffernan, Jay P. Sah, Pablo L. Ruiz, Adam A. Spitzig, Ewan Isherwood

SERC Research Reports

Status and history of the Ridge-Slough Mosaic The Florida Everglades is a large subtropical wetland with diverse hydrologic, edaphic, and vegetative characteristics. Historically, a significant portion of this system was a slow moving river originating from the Kissimmee River floodplain, flowing into the vast but shallow Lake Okeechobee, and draining south-southwest over extensive peatlands into Florida Bay (McVoy 2011). Human-induced alterations to the hydrologic regime, including reduction, stabilization, and impoundment of water flow through diversion and compartmentalization of water via canals and levees have degraded pre-drainage vegetation patterns and microtopographic structure (Davis and Ogden 1994, Ogden 2005, McVoy 2011). The ...


Assessment Of Acid Sulfate Soil Materials In The River Murray, Hume To Yarrawonga Region Of The Murray-Darling Basin, Nicholas J. Ward, Richard T. Bush, Leigh A. Sullivan, Diane M. Fyfe, J Coughran, M Tulau, Belinda Allman, David Morand, Vanessa NL Wong 2010 Southern Cross University

Assessment Of Acid Sulfate Soil Materials In The River Murray, Hume To Yarrawonga Region Of The Murray-Darling Basin, Nicholas J. Ward, Richard T. Bush, Leigh A. Sullivan, Diane M. Fyfe, J Coughran, M Tulau, Belinda Allman, David Morand, Vanessa Nl Wong

Southern Cross GeoScience

No abstract provided.


A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N. E. Spaulding, D. A. Meese, I. Baker, Paul Andrew Mayewski, Gordon S. Hamilton 2010 University of Maine - Main

A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N. E. Spaulding, D. A. Meese, I. Baker, Paul Andrew Mayewski, Gordon S. Hamilton

Earth Science Faculty Scholarship

Firn microstructure is accurately characterized using images obtained from scanning electron microscopy (SEM). Visibly etched grain boundaries within images are used to create a skeleton outline of the microstructure. A pixel-counting utility is applied to the outline to determine grain area. Firn grain sizes calculated using the technique described here are compared to those calculated using the techniques of Cow (1969) and Gay and Weiss (1999) on samples of the same material, and are found to be substantially smaller. The differences in grain size between the techniques are attributed to sampling deficiencies (e.g. the inclusion of pore filler in ...


Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl J. Kreutz, Erich Osterberg 2010 University of Maine - Main

Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl J. Kreutz, Erich Osterberg

Earth Science Faculty Scholarship

Samples were collected from a snow pit and shallow urn core near Kahiltna Pass (2970 m a.s.l.), Denali National Park, Alaska, USA, in May 2008. The record spans autumn 2003 to spring 2008 and reveals clusters of ice layers interpreted as summertime intervals of above-freezing temperatures. High correlation coefficients (0.75-1.00) between annual ice-layer thickness and regional summertime station temperatures for 4 years (n=4) indicate ice-layer thickness is a good proxy for mean and extreme summertime temperatures across Alaska, at least over the short period of record. A Rex-block (aka high-over-low) pattern, a downstream trough over ...


Subcritical Propagation And Coalescence Of Oil-Filled Cracks: Getting The Oil Out Of Low-Permeability Source Rocks, Z.-H. Jin, Scott E. Johnson, Z. Q. Fan 2010 University of Maine - Main

Subcritical Propagation And Coalescence Of Oil-Filled Cracks: Getting The Oil Out Of Low-Permeability Source Rocks, Z.-H. Jin, Scott E. Johnson, Z. Q. Fan

Earth Science Faculty Scholarship

We use a fracture mechanics model to study subcritical propagation and coalescence of single and collinear oil-filled cracks during conversion of kerogen to oil. The subcritical propagation distance, propagation duration, crack coalescence and excess oil pressure in the crack are determined using the fracture mechanics model together with the kinetics of kerogen-oil transformation. The propagation duration for the single crack is governed by the transformation kinetics whereas the propagation duration for the multiple collinear cracks may vary by two orders of magnitude depending on initial crack spacing. A large amount of kerogen (>90%) remains unconverted when the collinear cracks coalesce ...


Apparent Seasonal Cycle In Isotopic Discrimination Of Carbon In The Atmosphere And Biosphere Due To Vapor Pressure Deficit, Ashley P. Ballantyne, J. B. Miller, P. P. Tans 2010 University of Montana - Missoula

Apparent Seasonal Cycle In Isotopic Discrimination Of Carbon In The Atmosphere And Biosphere Due To Vapor Pressure Deficit, Ashley P. Ballantyne, J. B. Miller, P. P. Tans

Ecosystem and Conservation Sciences Faculty Publications

We explore seasonal variability in isotopic fractionation by analyzing observational data from the atmosphere and the biosphere, as well as simulated data from a global model. Using simulated values of atmospheric CO2 and its carbon isotopic composition, we evaluated different methods for specifying background concentrations when calculating the isotopic signature of source CO2 (δs) to the atmosphere. Based on this evaluation, we determined that free troposphere measurements should be used when available as a background reference when calculating δs from boundary layer observations. We then estimate the seasonal distribution of δs from monthly climatologies derived ...


Bite Marks Of The Giant Crocodylian Deinosuchus On Late Cretaceous (Campanian) Bones, David R. Schwimmer 2010 Columbus State University

Bite Marks Of The Giant Crocodylian Deinosuchus On Late Cretaceous (Campanian) Bones, David R. Schwimmer

Faculty Bibliography

The giant (~10 m) Late Cretaceous eusuchian crocodylians of the genus Deinosuchus are shown to have left large, blunt, sometimes penetrating bite marks on a significant number of sea turtle shells, and on several dinosaur specimens. The morphology of crocodylian bite marks is generally well documented, and the identification of bite traces specifically attributable to Deinosuchus may be made by reference to their size, age, habitat and prey selection. Deinosuchus species, and bite traces referable to the genus, are present on both sides of the Late Cretaceous Interior Seaway, and known only from Campanian deposits in the USA and northern ...


One Or Two Species Of The Giant Crocodylian Deinosuchus?, David R. Schwimmer 2010 Columbus State University

One Or Two Species Of The Giant Crocodylian Deinosuchus?, David R. Schwimmer

Faculty Bibliography

No abstract provided.


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