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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 ...


The Lavrion Mines: A Unique Site Of Geological And Mineralogical Heritage, Panagiotis Voudouris, Vasilios Melfos, Constantinos Mavrogonatos, Adonis Photiades, Eugenia Moraiti, Branko Rieck, Uwe Kolitsch, Alexandre Tarantola, Christophe Scheffer, Denis Morin, Olivier Vanderhaeghe, Paul G. Spry, James Ross, Konstantinos Soukis, Markos Vaxevanopoulos, Igor V. Pekov, Nikita V. Chukanov, Andreas Magganas, Marianna Kati, Athanasios Katerinopoulos, Stefanos Zaimis 2021 National and Kapodistrian University of Athens

The Lavrion Mines: A Unique Site Of Geological And Mineralogical Heritage, Panagiotis Voudouris, Vasilios Melfos, Constantinos Mavrogonatos, Adonis Photiades, Eugenia Moraiti, Branko Rieck, Uwe Kolitsch, Alexandre Tarantola, Christophe Scheffer, Denis Morin, Olivier Vanderhaeghe, Paul G. Spry, James Ross, Konstantinos Soukis, Markos Vaxevanopoulos, Igor V. Pekov, Nikita V. Chukanov, Andreas Magganas, Marianna Kati, Athanasios Katerinopoulos, Stefanos Zaimis

Geological and Atmospheric Sciences Publications

The Lavrion area corresponds to the western part of the Attic-Cycladic metamorphic belt, in the back-arc region of the active Hellenic subduction zone. Between the Eocene and the Miocene, metamorphic rocks (mainly marbles and schists) underwent several stages of metamorphism and deformation due to collision and collapse of the Cycladic belt. Exhumation during the Miocene was accommodated by the movement of a large-scale detachment fault system, which also enhanced emplacement of magmatic rocks, leading to the formation of the famous Lavrion silver deposits. The area around the mines shows the stacking of nappes, with ore deposition mainly localized within the ...


Reassessing Hydrothermal Heat Discharge And The Relationship Of Hot Springs In The North Oregon Cascades, Aaron Alexander Orr 2021 Portland State University

Reassessing Hydrothermal Heat Discharge And The Relationship Of Hot Springs In The North Oregon Cascades, Aaron Alexander Orr

Dissertations and Theses

Reservoir temperatures of hydrothermal systems in the Pacific Northwest reflect the feasibility of geothermal energy production and the tectonic framework of the region. Multicomponent geothermometry techniques were applied to new and historic water chemistry data in the north-central Oregon Western Cascades and the lower Wind River Valley in southern Washington in order to recalculate reservoir temperatures. Revised reservoir temperatures, water chemistry, and isotope data were used to determine relationships between hot springs in the north-central Oregon Cascades. Geothermal reservoir temperatures were estimated for the lower Wind River Valley (98.44 ± 0.96°C) and for Austin and Bagby Hot Springs ...


Evaluation Of Undeveloped Hard Coal Deposits And Estimation Of Hard Coal Reserves In The Upper Silesian Coal Basin, Poland, Tomasz Urych, Jarosław Chećko, Marek Rosa, Anna Wątor 2021 Central Mining Institute, Katowice, Poland

Evaluation Of Undeveloped Hard Coal Deposits And Estimation Of Hard Coal Reserves In The Upper Silesian Coal Basin, Poland, Tomasz Urych, Jarosław Chećko, Marek Rosa, Anna Wątor

Journal of Sustainable Mining

The article presents the results of works concerning evaluation of undeveloped deposits in the Upper Silesian Coal Basin and an estimation of hard coal reserves which can be developed by 2050. Evaluation of hard coal deposits was established on criterions choice and their score determination. On the basis of obtained the final score and after consultations with experts in the field of hard coal mining, there were selected three areas of undeveloped deposits with the amount of about 1.99 Gt (billion metric tons) of anticipated economic resources which can extend the coal reserve base located in the direct vicinity ...


Concentrated Lunar Resources: Imminent Implications For Governance And Justice, Martin Elvis, Alanna Krolikowski, Tony Milligan 2021 Missouri University of Science and Technology

Concentrated Lunar Resources: Imminent Implications For Governance And Justice, Martin Elvis, Alanna Krolikowski, Tony Milligan

History and Political Science Faculty Research & Creative Works

Numerous missions planned for the next decade are likely to target a handful of small sites of interest on the Moon's surface, creating risks of crowding and interference at these locations. The Moon presents finite and scarce areas with rare topography or concentrations of resources of special value. Locations of interest to science, notably for astronomy, include the Peaks of Eternal Light, the coldest of the cold traps and smooth areas on the far side. Regions richest in physical resources could also be uniquely suited to settlement and commerce. Such sites of interest are both few and small. Typically ...


Rock Glaciers And Related Cold Rocky Landforms: Overlooked Climate Refugia For Mountain Biodiversity, Stefano Brighenti, Scott Hotaling, Debra S. Finn, Andrew G. Fountain, Masaki Hayashi, David Herbst, Jasmine E. Saros, Lusha M. Tronstad, Constance I. Millar 2021 Free University of Bozen-Bolzano

Rock Glaciers And Related Cold Rocky Landforms: Overlooked Climate Refugia For Mountain Biodiversity, Stefano Brighenti, Scott Hotaling, Debra S. Finn, Andrew G. Fountain, Masaki Hayashi, David Herbst, Jasmine E. Saros, Lusha M. Tronstad, Constance I. Millar

Geology Faculty Publications and Presentations

Mountains are global biodiversity hotspots where cold environments and their associated ecological communities are predicted to be threatened by climate warming. Considerable research attention has been devoted to understanding the ecological effects of alpine glacier and snowfield recession. However, much less attention has been given to identifying climate refugia in mountain ecosystems where present-day environmental conditions will be maintained, at least in the near-term, as other habitats change. Around the world, montane communities of microbes, animals, and plants live on, adjacent to, and downstream of rock glaciers and related cold rocky landforms (CRL). These geomorphological features have been overlooked in ...


The Geology, Geochemistry, And Origin Of The Porphyry Cu-Au-(Mo) System At Vathi, Serbo-Macedonian Massif, Greece, Christos L. Stergiou, Vasilios Melfos, Panagiotis Voudouris, Paul G. Spry, Lambrini Papadopoulou, Alexandros Chatzipetros, Katerina Giouri, Constantinos Mavrogonatos, Anestis Filippidis 2021 University of Thessaloniki

The Geology, Geochemistry, And Origin Of The Porphyry Cu-Au-(Mo) System At Vathi, Serbo-Macedonian Massif, Greece, Christos L. Stergiou, Vasilios Melfos, Panagiotis Voudouris, Paul G. Spry, Lambrini Papadopoulou, Alexandros Chatzipetros, Katerina Giouri, Constantinos Mavrogonatos, Anestis Filippidis

Geological and Atmospheric Sciences Publications

The Vathi porphyry Cu-Au ± Mo mineralization is located in the Serbo-Macedonian metallogenic province of the Western Tethyan Metallogenic Belt. It is mainly hosted by a latite and is genetically associated with a quartz monzonite intrusion, which intruded the basement rocks of the Vertiskos Unit and the latite, 18 to 17 Ma ago. A phreatic breccia crosscuts the latite. The quartz monzonite was affected by potassic alteration, whereas the latite was subjected to local propylitic alteration. Both styles of alteration were subsequently overprinted by intense sericitic alteration. M-type and A-type veins are spatially associated with potassic alteration, whereas D-type veins are ...


The Earth, William Clement 2021 University of Massachusetts Amherst

The Earth, William Clement

Sustainability Education Resources

The Earth is a 4-credit introduction to the Geosciences. This course is required for several majors in the College of Natural Science at the University of Massachusetts Amherst. These majors include Earth Systems, Environmental Science, and Geology. The course also fulfills a 4-credit Physical Science (PS) General Education requirement and may be an elective science course in a number of other majors. Our goal in Geology 101 is to provide a basic knowledge of how the Earth works, the role of the geologist in contemporary society, and the application of geologic knowledge in solving real world problems. These are broad ...


Trondhjemite Leucosomes Generated By Partial Melting Of A Hornblende-Gabbro (Alvand Plutonic Complex, Hamedan, Nw Iran), Adel Saki, Federico Lucci, Mirmohammad Miri, John C. White 2021 Shahid Chamran University of Ahvaz, Iran

Trondhjemite Leucosomes Generated By Partial Melting Of A Hornblende-Gabbro (Alvand Plutonic Complex, Hamedan, Nw Iran), Adel Saki, Federico Lucci, Mirmohammad Miri, John C. White

EKU Faculty and Staff Scholarship

This work describes the petrogenesis of in situ and in-source trondhjemite leucosomes generated by low-degree partial melting of the Jurassic Cheshmeh-Ghasaban hornblende-gabbros in the northern Alvand batholith (Hamedan, NW Iran). These leucosomes occur in a metatexite migmatite as patches, net-structures, veinlets, and dikes at scales ranging from a few millimetres to a few metres. They have high SiO2 (mean ≈ 78 wt%) and Na2O (4–5 wt%) with low Al2O3 (<15 wt%), K2 O (<1.5 wt%), Sr (33–267 ppm), Eu (0.31–0.62 ppm) and heavy REE (<4 ppm) contents similar to typical low-Al2O3 trondhjemites. Batch-melting models indicate these leucosomes are the result of ≈1-2% partial melting of the hornblende-gabbro, whereas thermobarometric modelling constrains their petrogenesis in the field of hornblende hornfels-facies metamorphism (pressure ≈3.0–4.5 kbar and temperature ≈700-750°C). On a wider scale, our results document natural trondhjemites generated in the upper crust by amphibole-dehydration melting of a mafic source at temperature conditions close to the solidus, filling the existing gap of data in low-pressure (P < 5kbar) and lowtemperature (T < 800°C) amphibole-dominated partial melting experiments. The genesis of these trondhjemites is then discussed with respect to the Mesozoic evolution of the Alvand plutonic complex.


Evolution Of The Magma System Of Pantelleria (Italy) From 190 Ka To Present., Nina J. Jordan, John C. White, Ray Macdonald, Silvio G. Rotolo 2021 University of Leicester

Evolution Of The Magma System Of Pantelleria (Italy) From 190 Ka To Present., Nina J. Jordan, John C. White, Ray Macdonald, Silvio G. Rotolo

EKU Faculty and Staff Scholarship

The eruptive history of Pantelleria has been marked by the eruption of nine peralkaline ignimbrites, with inter-ignimbrite episodes from small, local volcanic centres. New whole-rock geochemical data are presented for seven ignimbrites and used with published data for younger units to track compositional changes with time. From ∼190 ka, silicic magmatism was dominated by comenditic trachyte to comendite compositions, evolving along generally similar liquid lines of descent (LLOD). The final ignimbrite, the Green Tuff (∼46 ka), was tapped from a compositionally zoned pantelleritic upper reservoir to a trachytic mush zone. Younger (20–7 ka) silicic magmatism has been relatively small ...


Volcanological Evolution Of Pantelleria Island (Strait Of Sicily) Peralkaline Volcano: A Review, Silvio G. Rotolo, Stéphane Scaillet, Fabio Speranza, John C. White, Rebecca Williams, Nina J. Jordan 2021 Universita degli Studi di Palermo

Volcanological Evolution Of Pantelleria Island (Strait Of Sicily) Peralkaline Volcano: A Review, Silvio G. Rotolo, Stéphane Scaillet, Fabio Speranza, John C. White, Rebecca Williams, Nina J. Jordan

EKU Faculty and Staff Scholarship

Pantelleria volcano has a particularly intriguing evolutionary history intimately related to the peralkaline composition of its explosively erupted magmas. Due to the stratigraphic complexity, studies over the last two decades have explored either only the pre-Green Tuff ignimbrite volcanism or the post-Green Tuff activity. We here focus on the whole evolutionary history, detailing the achievements since the first pioneering studies, in order to illustrate how the adoption and integration of progressively more accurate methods (40Ar/39Ar, paleomagnetism, petrography, and detailed field study) have provided many important independent answers to unresolved questions. We also discuss rheomorphism, a distinct feature at Pantelleria ...


Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright 2021 University of San Diego

Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright

Theses

Anomalously elevated arsenic concentrations occur at an abandoned artisanal mine site in an open space recreational park in urban San Diego County, California. Although mining at the site ceased 100 years ago little to no remediation efforts took place leaving shafts, adits, waste piles and derelict infrastructure accessible by inquisitive hikers and adventurers frequenting Black Mountain Open Space Park. This study evaluates the geochemical mechanisms of As transport downgradient from the mine and examines the contribution of both climate and urbanization on the restriction of As mobility. Sediment As concentrations reach 2,320 mg/kg (483 times background crustal concentrations ...


Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward 2021 The University of Akron

Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward

Williams Honors College, Honors Research Projects

Analyzing the strength of synthetic quartz is essential to understanding the strength of natural milky quartz, which likely controls the strength of Earth’s continental crust. Synthetic quartz is sometimes used for deformation experiments because it has a homogenous water distribution unlike natural milky quartz. The purpose of this study is to determine if annealing synthetic quartz at T = 600°C will convert the water in synthetic quartz to free water, like milky quartz, but with little water loss. Following two annealing experiments at Texas A&M University, I performed four annealing experiments to measure the water content of five ...


Recent Flooding Events On The Chagrin And Cuyahoga Rivers, Ohio, Kayley Martin 2021 The University of Akron

Recent Flooding Events On The Chagrin And Cuyahoga Rivers, Ohio, Kayley Martin

Williams Honors College, Honors Research Projects

From the 1910s through the 1980s, the number of intense daily precipitation events in the United States remained constant, however, since the 1980s there has been an increasing trend in intense single-day precipitation events (U.S Environmental Protection Agency, 2016). One outcome of intense precipitation events is river flooding, particularly in the upper Midwest region where floods have increased in magnitude and frequency (U.S Environmental Protection Agency, 2016). In this thesis project, recent flooding history on the Chagrin and Cuyahoga Rivers in Ohio was studied to expand on previous research that observed an abrupt increase in high magnitude flood ...


Answers In The East: An Examination Of China's Renewable Energy And Its Application To Central Appalachia, Lillian Hamm 2021 Western Kentucky University

Answers In The East: An Examination Of China's Renewable Energy And Its Application To Central Appalachia, Lillian Hamm

Mahurin Honors College Capstone Experience/Thesis Projects

While much of China’s electrification has depended on coal, recent decades illustrate the country is heavily investing in and implementing renewable energy as a power source. Even China’s coal-rich provinces, like the northeastern province of Shanxi, have been making the transition to renewable energy. The central Appalachian states comprised of eastern Kentucky, West Virginia, western Virginia, and northeastern Tennessee share many characteristics with China’s Shanxi province including economic resources, climate, and geography. Yet, central Appalachia has not been able to easily transition to renewable energy. However, there are various cultural, political, and technological differences between the two ...


Annual Report 2020 Conservation And Survey Division, Robert Matthew Joeckel 2021 University of Nebraska - Lincoln

Annual Report 2020 Conservation And Survey Division, Robert Matthew Joeckel

Conservation and Survey Division

The Conservation and Survey Division (Nebraska Geological Survey), the natural resource survey component of the School of Natural Resources, is a unique, multi-disciplinary research, service and data-collection organization established by state statute in 1921.

The Division's mission is to investigate and record information about Nebraska's geologic history, its rock and mineral resources, the quantity and quality of its water resources, land cover and other aspects of its geography, as well as the nature, distribution and uses of its soils.


Analyzing The Multipath Of Gps Time Series To Study Snow Properties, Ashlesha Khatiwada 2021 University of Montana

Analyzing The Multipath Of Gps Time Series To Study Snow Properties, Ashlesha Khatiwada

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Thousands of Global Positioning System (GNSS) receivers worldwide record signals sent by satellites to infer how each receiver (and the ground they are attached to) moves over time. The motion of GNSS receivers is used for many purposes, including studying tectonic deformation and changes in Earth's shape caused by surface loading. In this project, reflected wave arrivals contained within the multipath signal of GNSS time series are extracted and analyzed to advance understanding of snow properties in mountainous regions of Montana/Idaho, USA. Analyzing reflected signals in GNSS series has the potential to reveal properties of local snowpack, such ...


Salt Marsh Hydrogeology: A Review, Julia Guimond, Joseph Tamborski 2021 Old Dominion University

Salt Marsh Hydrogeology: A Review, Julia Guimond, Joseph Tamborski

OEAS Faculty Publications

Groundwater–surface water exchange in salt marsh ecosystems mediates nearshore salt, nutrient, and carbon budgets with implications for biological productivity and global climate. Despite their importance, a synthesis of salt marsh groundwater studies is lacking. In this review, we summarize drivers mediating salt marsh hydrogeology, review field and modeling techniques, and discuss patterns of exchange. New data from a Delaware seepage meter study are reported which highlight small-scale spatial variability in exchange rates. A synthesis of the salt marsh hydrogeology literature reveals a positive relationship between tidal range and submarine groundwater discharge but not porewater exchange, highlighting the multidimensional drivers ...


Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras 2021 West Virginia University

Refining The Sedimentology And Geochemistry Of The Mid-Permian Blaine Formation Of The Rebecca K. Bounds Core From Greeley County, Kansas, Brigitte Petras

Graduate Theses, Dissertations, and Problem Reports

Red siliciclastics and evaporites of Permian Nippewalla Group in mid-continental US were deposited in western equatorial Pangea. Previous studies of these rocks record Permian air temperatures as high as 73 °C, saline lake waters with a pH as low as ~1, and sedimentology that shows arid conditions. This current study conducts detailed sedimentological observations and geochemical analyses of the Blaine Formation of the Nippewalla Group. The Rebecca K. Bounds core from west-central Kansas is used to interpret the depositional environments and diagenetic history of the Blaine Formation.

The lithologies of the Blaine Formation, listed in order of most to least ...


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