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Glaciers Of The Olympic Mountains, Washington - The Past And Future 100 Years, Andrew G. Fountain, Christina Gray, Bryce Allen Glenn, Brian Menounos, Justin Pflug, Jon L. Riedel 2021 Portland State University

Glaciers Of The Olympic Mountains, Washington - The Past And Future 100 Years, Andrew G. Fountain, Christina Gray, Bryce Allen Glenn, Brian Menounos, Justin Pflug, Jon L. Riedel

Geology Faculty Publications and Presentations

In 2015, the Olympic Mountains contain 255 glaciers and perennial snowfields totaling 25.34 ± 39 0.27 km2, half of the area in 1900, and about 0.75 ± 0.19 km3 of ice. Since 1980, glaciers shrank 40 at a rate of -0.59 km2 yr-1 during which 35 glaciers and 16 perennial snowfields disappeared. Area changes of Blue Glacier, the largest glacier in the study region, was a good proxy for glacier change of the entire region. A simple mass balance model of the glacier, based on monthly air temperature and precipitation, correlates with glacier area change. The mass ...


Bat Guano Minerals And Mineralization Processes In Chameau Cave, Eastern Morocco, Philippe Audra, Vasile Heresanu, Lionel Barriquand, Mohamed El Kadiri Boutchich, Stephane Jaillet, Edwige Pons-Branchu, Pavel Bosak, Hai Cheng, R Lawrence Edwards, Michel Renda 2021 University of Nice Sophia Antipolis (France)

Bat Guano Minerals And Mineralization Processes In Chameau Cave, Eastern Morocco, Philippe Audra, Vasile Heresanu, Lionel Barriquand, Mohamed El Kadiri Boutchich, Stephane Jaillet, Edwige Pons-Branchu, Pavel Bosak, Hai Cheng, R Lawrence Edwards, Michel Renda

International Journal of Speleology

The decay of bat guano deposits in caves produces mineral accumulations, mainly phosphates and secondary sulfates. Chameau Cave, Eastern Morocco, is located in the semi-arid Bni Snassen Mountains. It is composed of semi-active and dry passages, and is featured by strong condensation-corrosion on the walls, presence of fluvial sediments, and old corroded flowstones. Due to forced and convective airflow, the cave is generally very dry, with some damp sites related to condensation. Samples collected on the surface of different passages and along two sediment profiles yielded minerals related to bat guano decay. On recent or fresh guano, precursor minerals correspond ...


Application Of The Global Srtm And Aw3d30 Digital Elevation Models To Mapping Folds At Cave Sites, Mark J. Abolins, Albert E. Ogden 2021 Middle Tennessee State University, USA

Application Of The Global Srtm And Aw3d30 Digital Elevation Models To Mapping Folds At Cave Sites, Mark J. Abolins, Albert E. Ogden

International Journal of Speleology

A novel method to map and quantitatively describe very gentle folds (limb dip <5o) at cratonic cave sites was evaluated at Snail Shell and Nanna Caves, central Tennessee, USA. Elevations from the global SRTM digital terrain model (DTM) were assigned to points on late Ordovician geologic contacts, and the elevations of the points were used to interpolate 28 m cell size natural neighbor digital elevation models (DEM’s) of the contacts. The global Forest Canopy Height Dataset was subtracted from the global 28 m cell size AW3D30 digital surface model (DSM) to create a DTM, and that DTM was applied ...


Reconstructing Surface Water Carbonate Ion Concentration Changes In The Eastern Equatorial Pacific Across Glacial Transitions, Lenzie Gail Ward 2021 Old Dominion University

Reconstructing Surface Water Carbonate Ion Concentration Changes In The Eastern Equatorial Pacific Across Glacial Transitions, Lenzie Gail Ward

OEAS Theses and Dissertations

Today, the eastern equatorial Pacific (EEP) plays a critical role in the global CO2 budget as a major source of CO2 to the atmosphere, but recent studies suggest the region may shift to a sink for atmospheric CO2 under different climate states. Here, I focus on two transitional periods, the last deglaciation (25 kyr to present) and last glaciation (the Marine Isotope Stage (MIS) 5a-4 transition, 96 to 60 kyr), to investigate how the carbon system in the EEP responds to major climate changes. I measured B/Ca ratios in the planktic foraminifera Globigerina bulloides from core ...


An Investigation On Flow Field Partitioning Related To The Rheological Heterogeneities And Its Application To Geological Examples, Ankit Bhandari 2021 The University of Western Ontario

An Investigation On Flow Field Partitioning Related To The Rheological Heterogeneities And Its Application To Geological Examples, Ankit Bhandari

Electronic Thesis and Dissertation Repository

Earth’s lithosphere is heterogeneous and composed of rheologically distinct elements at various scales of observations. This causes the flow of rocks to vary with space and time, which may influence the formation of various kinds of geological rock records. This thesis provides quantitative solutions to some first-order problems in structural geology regarding this heterogeneous flow variation and thereby the development of various geological rock records at different scales of observations.

Pressure in a rheologically heterogeneous element may deviate from its ambient value and if significant, may influence the metamorphic assemblages. This might cause problems in the routine use of ...


Collaborative Research: Identifying Shallow Slow Slip Using Hematite Tectures And (U-Th)/He Thermochonometry Of Exhumed And Experimental Faults, Alexis Ault 2021 Utah State University

Collaborative Research: Identifying Shallow Slow Slip Using Hematite Tectures And (U-Th)/He Thermochonometry Of Exhumed And Experimental Faults, Alexis Ault

Funded Research Records

No abstract provided.


Molecules To Mountains: A Multi-Proxy Investigation Into Ancient Climate And Topography Of The Pacific Northwest, Usa, Alexander McLean, John Bershaw 2021 Portland State University

Molecules To Mountains: A Multi-Proxy Investigation Into Ancient Climate And Topography Of The Pacific Northwest, Usa, Alexander Mclean, John Bershaw

Geology Faculty Publications and Presentations

We characterize the topographic evolution of the Pacific Northwest, United States, during the Cenozoic. New paleosol carbonate stable isotope (δ18O) results from central Oregon are presented, along with published proxy data, including fossil teeth, smectites, and carbonate concretions. We interpret a polygenetic history of Cascade Mountain topographic uplift along-strike, characterized by: 1) Steady uplift of the Washington Cascades through the Cenozoic due long-term arc rotation and shortening against a Canadian buttress, and 2) Uplift of the Oregon Cascades to similar-to-modern elevations by the late Oligocene, followed by topographic stagnation as extension developed into the Neogene. Since the Miocene, meteoric water ...


Glacier Clear Ice Bands Indicate Englacial Channel Microbial Distribution, Gilda Varliero, Alexandra Holland, Gary L. A. Barker, Marian L. Yallop, Andrew G. Fountain, Alexandre M. Anesio 2021 University of Bristol

Glacier Clear Ice Bands Indicate Englacial Channel Microbial Distribution, Gilda Varliero, Alexandra Holland, Gary L. A. Barker, Marian L. Yallop, Andrew G. Fountain, Alexandre M. Anesio

Geology Faculty Publications and Presentations

Distant glacial areas are interconnected by a complex system of fractures and water channels which run in the glacier interior and characterize the englacial realm. Water can slowly freeze in these channels where the slow freezing excludes air bubbles giving the ice a clear aspect. This ice is uplifted to the surface ablation zone by glacial movements and can therefore be observed in the form of clear surface ice bands. We employed an indirect method to sample englacial water by coring these ice bands. We were able, for the first time, to compare microbial communities sampled from clear (i.e ...


Deriving Melt Rates At A Complex Ice Shelf Base Using In Situ Radar: Application To Totten Ice Shelf, Irena Vaňková, Sue Cook, J. Paul Winberry, Keith W. Nicholls, Benjamin K. Galton-Fenzi 2021 British Antarctic Survey, Natural Environment Research Council

Deriving Melt Rates At A Complex Ice Shelf Base Using In Situ Radar: Application To Totten Ice Shelf, Irena Vaňková, Sue Cook, J. Paul Winberry, Keith W. Nicholls, Benjamin K. Galton-Fenzi

Geological Sciences Faculty Scholarship

A phase-sensitive radar (ApRES) was deployed on Totten Ice Shelf to provide the first in situ basal melt estimate at this dynamic East Antarctic ice shelf. Observations of internal ice dynamics at tidal time scales showed that early arrivals from off-nadir reflectors obscure the true depth of the ice shelf base. Using the observed tidal deformation, the true base was found to lie at 1,910–1,950-m depth, at 350–400 m greater range than the first reflection from an ice-ocean interface. The robustness of the basal melt rate estimate was increased by using multiple basal reflections over the ...


Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal 2021 University of Nebraska - Lincoln

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal

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Rock Glen Wildlife Area: A Landscape History, Gerry Steinauer, Robert Diffendal Jr. 2021 University of Nebraska-Lincoln

Rock Glen Wildlife Area: A Landscape History, Gerry Steinauer, Robert Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Nestled in the hills of southern Jefferson County, Rock Glen Wildlife Management Area, as its name implies, is a rocky land shaped by ancient geological forces, among them, meandering tropical rivers and grinding glacial ice. Euro-American settlers in the region arrived to a picturesque scene: rolling hills cloaked in tallgrass prairie fingered by glens, narrow valleys and canyons, filled with sprawling bur oaks. Too rocky to plow, southern Jefferson County has survived as an island of prairie amidst a sea of cropland. Settlement was not kind to the land. Fire suppression allowed eastern red cedars and other trees to spread ...


Pacific Northwest Littoral Data, Curt D. Peterson, Kara E. P. Kingen 2021 Portland State University

Pacific Northwest Littoral Data, Curt D. Peterson, Kara E. P. Kingen

Geology Faculty Datasets

This document contains five data tables in PDF file formats, that are used to characterize littoral subcell (beach, river mouth, and inner-shelf) conditions in the Pacific Northwest (PNW) region (Washington, Oregon, and Northern California). These data have been compiled from pre-existing data sets (see citations in Table notes and References, below) for the purposes of predicting possible beach erosion from potential future sea level rise (SLR), as introduced in Kingen (2018) and Peterson et al. (2019, 2020a,b). The five data tables include Heavy-mineral tracers (Table 1), Heavy-mineral data (normalized) (Table 2), Subcell beach profile settings (Table 3), Subcell beach ...


Geology And Fossils Of North Central Texas (Fort Worth To Mineral Wells): Texas Academy Of Science February 28 2021, R. LaRell Nielson 2021 Stephen F Austin State University

Geology And Fossils Of North Central Texas (Fort Worth To Mineral Wells): Texas Academy Of Science February 28 2021, R. Larell Nielson

Faculty Publications

The 2021 Texas Academy of Science Geology field trip will be a virtual field trip that you may run at any time. It will have two parts;Part 1 consists of a video discussion of each stop( https://www.youtube.com/watch?v=EJKSgqtLvw0)and Part 2 consists of this field trip guidebook (for use when visiting each of the locations). The field trip will start at Holiday Park,near Benbrook,southwest of Fort Worth,Texas, and will end at the Mineral Wells Fossil Park, west of Minerals Wells, Texas. T


A Reimagining Of The Chacoan World, Larry Benson, Richard W. Loose 2021 University of Colorado at Boulder

A Reimagining Of The Chacoan World, Larry Benson, Richard W. Loose

USGS Staff -- Published Research

A new paradigm of the Chacoan world is presented, wherein Chaco Canyon is considered to be a mostly unoccupied architectural complex that functioned primarily as a pilgrimage destination. Chaco was the political, religious, and social focal point of people living in outlying regions. The resident population of the Canyon consisted of a small number of caretakers, charged with maintaining great house structures, food supplies, and their ceremonial contents. Chacoan chiefdoms were mostly located in large, well-watered, agriculturally-based communities situated at the base of mountains that ring the San Juan Basin, e.g., the Chuskas. Chiefly elites lived year-round in those ...


Soils Laboratory Manual: K-State Edition, Version 2.0, Colby J. Moorberg, David A. Crouse 2021 Kansas State University

Soils Laboratory Manual: K-State Edition, Version 2.0, Colby J. Moorberg, David A. Crouse

NPP eBooks

The Soils Laboratory Manual, K-State Edition is designed for students in undergraduate, introductory soil science courses. The manual highlights the multidisciplinary aspects of soil science with laboratories focused on soil formation, classification, and mapping; soil physics, soil biology; soil chemistry; and soil fertility and management. The lab manual includes 16 different laboratories, each one starting with an introduction and pre-lab assignment, followed by in-lab activities, and complimented by a post-lab assignment. In-lab activities involve field trips, experiments, observation stations, or problem sets. Post-lab assignments include online quizzes, problem sets, or laboratory summary reports.

Version 2 of the lab manual exhibits ...


Plastic Debris In The Laurentian Great Lakes System, North America: Analysis Of Types, Abundances, And Sources, Ian A. Arturo 2021 The University of Western Ontario

Plastic Debris In The Laurentian Great Lakes System, North America: Analysis Of Types, Abundances, And Sources, Ian A. Arturo

Electronic Thesis and Dissertation Repository

Understanding plastic pollution in the Laurentian Great Lakes system requires investigation of all plastic debris sizes and categories. Visible polymeric debris (VPD) mainly characterize shorelines, and microplastics (MPs;mm) are found in benthic and beach sediment. Field sampling of VPD from all five Great Lakes, visual and chemical identification of VPD types, and implementation of a matrix scoring technique (MST) indicate that plastic industries, urban areas, and shoreline recreation are major sources of VPD. Sampling for MPs in the St. Clair system, followed by preliminary density separation, and microscopy, suggest that wastewater treatment plants are a major source. This work ...


The Geologic Times, Vol. 8, Sara Mana 2021 Salem State University

The Geologic Times, Vol. 8, Sara Mana

Earth Science Association

The eight issue of the Earth Science Association's newsletter, The Geologic Times.

Contents:

Silurian Seaways and Early Shallow Marine Life by Shadya El-Ashkar

Mineral of the Month: Malachite! by Kristen Anastopoulos

What is new in the ESA community?!

Working in the Environmental Consulting Industry as a Geologist by Sara Barrientos

Geology Word Search


Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel 2021 University of Nebraska-Lincoln

Nebraska Statewide Groundwater-Level Monitoring Report 2020, Aaron R. Young, Mark E. Burbach, Leslie M. Howard, Sue Olafsen Lackey, Robert Matthew Joeckel

Conservation and Survey Division

The term “groundwater” has come to be all but synonymous with Nebraska. Nearly three-quarters of the total volume of the High Plains Aquifer lies beneath the state. Groundwater maintains our streams, our ecosystems, our people, and our vitally important agricultural economy. Nebraska’s total groundwater resource is vast, yet it is also vulnerable to natural and anthropogenic changes, necessitating a long-term commitment to wise management through informed decision-making. Monitoring, studying, and reporting form the essential basis for such management and, ultimately, for meeting the myriad challenges presented by change.


Optimization Of The Distribution Of Drilling Boreholes In Methane Production From Coal Seams, Anna Wątor, Jarosław Chećko, Tomasz Urych 2021 Central Mining Institute, Katowice, Poland

Optimization Of The Distribution Of Drilling Boreholes In Methane Production From Coal Seams, Anna Wątor, Jarosław Chećko, Tomasz Urych

Journal of Sustainable Mining

The paper presents an evaluation of methane production from coal seams. The Warszowice-PawłowicePółnoc deposit was selected for numerical modelling of methane production. The numerical model was made for a fragment of this deposit of about 2 km2. The numerical model was constructed for 6 seams. Three deposits were selected for simulation of methane production. Three horizontal boreholes were designed within the model area, referring to the existing Suszec-19 borehole. A number of simulations related to methane production from the selected deposits were performed. They included different variants of the number of boreholes and also took into account the z-pinnate ...


When Dinosaurs Walked Through Diamonds: Constraining The Age Of Early Cretaceous Footprints In Volcanic Crater Sediments, Yasmin Jackson 2021 Southern Methodist University

When Dinosaurs Walked Through Diamonds: Constraining The Age Of Early Cretaceous Footprints In Volcanic Crater Sediments, Yasmin Jackson

SMU Journal of Undergraduate Research

The volcanic rocks of the Catoca Diamond Mine, northeastern Angola, were formed in an eruption ~118 million years ago. Above these rocks, researchers discovered Early Cretaceous mammalian, crocodilian, and sauropod dinosaur footprints in crater lake sediments. These footprints are among the relatively few vertebrate fossils from the Cretaceous Period (145-66 million years ago) found in Sub-Saharan Africa. The ~118 million-year-old age, which is the maximum age of the footprints, is provided by the uranium and lead isotope ratios in the zircon crystals from these volcanic rocks. The presence of dinosaur footprints limits the minimum age to 66 million years ago ...


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