Migmatite-Like Textures In Anthracite: Further Evidence For Low-Grade Metamorphic Melting And Resolidification In High-Rank Coals, James C. Hower, Susan M. Rimmer, Maria Mastalerz, Nicola J. Wagner
Center for Applied Energy Research Faculty Publications
Previous studies demonstrated that melting, initiated by supercritical fluids in the 375–400 °C range, occurred as part of anthracite metamorphism in the Appalachian Basin. Based on the known behavior of vitrinite at high temperatures and, to a lesser extent, at high pressures, it was determined that the duration of the heating, melting, and resolidification event was about 1 h. In the current study, featureless vitrinite within banded maceral assemblages demonstrates the intimate association of melted and resolidified vitrinite with anthracite-rank macerals. By analogy with metamorphosed inorganic rocks, such associations represent diadysites and embrechites, i.e., cross-cutting and layered migmatites ...
The Biggest Snowball Fight In Earth History: Stratigraphy, Facies Analysis, And Geochronology Of The Pocatello Formation, Matthew W. Ellison
All Graduate Theses and Dissertations
The Snowball Earth Hypothesis details a time in Earth’s history (the Cryogenian period) where the entire planet was encapsulated by kilometer thick ice sheets for two, multi-million-year glaciations. The first, known as the Sturtian, lasted from 717 – 660 million years ago while the second, known as the Marinoan, lasted form approximately 650 – 635 million years ago. Snowball Earth was caused by a few processes that sort of built upon each other: Rodinia began splitting apart ~740 million years ago which allowed for increased rates of silicate weathering. High rates of silicate weathering resulted in CO2 drawdown which in ...
Spatial And Temporal Patterns Of River Incision And Terrace Deposition In Response To Climate And Tectonics In Southern Taiwan, Dominique M. Shore
All Graduate Theses and Dissertations
Geologists often look at the Earth’s surface to understand the underlying processes that cause mountain formation. As tectonic forces drive uplift of Earth’s surface, processes of erosion transport sediment to lower elevations. Climate can play a large role in landscape formation as well as increased precipitation, accelerating rates of erosion. Rivers leave markers of landscape evolution through terrace landforms, former river floodplains that are left behind when rivers incise into a valley. To better understand landscape response to uplift, this research investigated the initial linkages between uplift, hillslope erosion (mass wasting) and river incision. At some point, it ...
Bedrock To Buildings, 2021 University of Maine at Farmington
Bedrock To Buildings, Bryer Carlson
Michael D. Wilson Symposium
This poster explores Maine's bedrock in relation to the state's infrastructure.
Mapping And Analysis Of Structural Bmp's In The Root River Watershed, Mn, 2021 Winona State University
Mapping And Analysis Of Structural Bmp's In The Root River Watershed, Mn, Megan Otten
Ramaley Research Celebration
Spanning almost 1,700 square miles over six different counties (Dodge, Filmore, Houston, Olmsted and Winona) in southeastern Minnesota, the Root River Watershed is one of the state’s largest watersheds draining into the Mississippi River. The Root River Watershed is within the Driftless area, which has a unique set of characteristics that present certain challenges when it comes to watershed mapping and management. The Driftless area, consisting of Paleozoic limestone, dolostone and St. Peter sandstone, is characterized by its karst features and highly incised, heavily forested valleys. Soil erosion and farm field runoff are two of the Minnesota Pollution ...
Geochemical Classification Of The East Central Minnesota Batholith, 2021 Winona State University
Geochemical Classification Of The East Central Minnesota Batholith, Simon Taylor
Ramaley Research Celebration
The East Central Minnesota Batholith (ECMB) is a series of granitic plutons exposed along the Sauk river valley near St. Cloud Minnesota. The currently accepted understanding of the processes that generated these plutons relies on the location and age of emplacement. The location of the ECMB is within a terrain that was accreted onto the North American continent during the Penokean orogeny between 1875 to 1835 Ma (Van Schmus, 1976). However the granites within the ECMB are younger than that having ages between 1772 Ma and 1783 Ma (Holm et al., 2005), similar to ages for the Yavapai orogeny occurring ...
Glaciers Of The Olympic Mountains, Washington - The Past And Future 100 Years, 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, 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, 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 ...5
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.
Publications And Other Works By R. F. Diffendal, Jr., 2021 University of Nebraska - Lincoln
Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal
Papers in Natural Resources
Chapters in Books
Newspaper and Other Articles
Manuscripts Accepted (A) , Submitted (S) or In Preparation (P)
Geologic Maps in Press
Updated March 2021
Rock Glen Wildlife Area: A Landscape History, 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, 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, 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
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, 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, 2021 Kansas State University
Soils Laboratory Manual: K-State Edition, Version 2.0, Colby J. Moorberg, David A. Crouse
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 ...
Nebraska Statewide Groundwater-Level Monitoring Report 2020, 2021 University of Nebraska at 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.
The Geologic Times, Vol. 8, 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.
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
Optimization Of The Distribution Of Drilling Boreholes In Methane Production From Coal Seams, 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, 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 ...