Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Geology (5)
- Cores (2)
- Glaciers (2)
- Lakes (2)
- Rocks (2)
-
- Adirondacks (1)
- Alpha (1)
- Amphibolite (1)
- Blåhø Nappe (1)
- Collapse (1)
- Contamination (1)
- Deposit (1)
- Energy (1)
- Environmental monitoring (1)
- Exhumation (1)
- Fault (1)
- Figure (1)
- Fjord (1)
- Fossil (1)
- Garnet (1)
- Glacial (1)
- Grain (1)
- Groundwater; stable isotopes; hydrology; water resources; isoscape (1)
- Holocene (1)
- Hydrology (1)
- Ice Age (1)
- Island (1)
- Junín (1)
- Lake (1)
- Lithology (1)
Articles 1 - 14 of 14
Full-Text Articles in Physical Sciences and Mathematics
Groundwater Isotopes Across Scales: Continent-Wide Modeling And Local Field Characterization, Jaclyn Gehring
Groundwater Isotopes Across Scales: Continent-Wide Modeling And Local Field Characterization, Jaclyn Gehring
Honors Theses
Groundwater is one of the world’s most important natural resources. The use of stable water isotopes (𝛿2H and 𝛿18O) as natural tracers through the water cycle has provided a unique observational technique for characterizing hydrological processes and establishing connections between water distribution systems and their respective environmental sources. Groundwater contains information about the timing and efficiency of recharge, allowing for the use of isotopes to understand the physical hydrology and climatic influences on such processes in places with groundwater isotope measurements. We estimate the seasonal recharge proportion and efficiency at thousands of locations across the U.S., …
Petrology And Thermodynamic Modeling Of Amphibolite Facies Rocks Of The Blåhø Nappe Of The Middle Allochthon, Scandinavian Caledonides In Norway, Maria Van Nostrand
Petrology And Thermodynamic Modeling Of Amphibolite Facies Rocks Of The Blåhø Nappe Of The Middle Allochthon, Scandinavian Caledonides In Norway, Maria Van Nostrand
Honors Theses
The Scandinavian Caledonides are an orogenic belt formed when Baltica collided with Laurentia during the late Silurian to early Devonian (Scandian, ~426–390 Ma, Gee et al., 2008). The thrust sheets forming the belt are divided into the Lower, Middle, Upper, and Uppermost Allochthons derived, respectively, from the Baltican margin and regions progressively farther outboard. This study focuses on the Blåhø Nappe, part of the Middle Allochthon, which is generally presumed to have been from an Early Paleozoic volcanic arc off the Baltican margin. The Blåhø Nappe contains abundant igneous and sedimentary rocks, metamorphosed almost entirely at amphibolite facies, but contains …
Characterization Of Glacial Sediments From A 700,000-Year-Old Lake Junín Drill Core, Tshering Lama Sherpa
Characterization Of Glacial Sediments From A 700,000-Year-Old Lake Junín Drill Core, Tshering Lama Sherpa
Honors Theses
Lake Junín (11.0°S, 76.2°W) is an intermontane lake at an elevation of 4085 masl in Junín, Peru. The lake spans ~300 km2 and has a water depth of ~12m. It is dammed at its northern and southern ends by glacial alluvial fans that have been dated >250 ka, indicating that the lake is at least this old. Lake Junín has never been overridden by ice in the past 1 million years making it one of the few lakes in the tropical Andes that predates the last maximum extent of glaciation and has a continuous record of waxing and waning of …
Provenance Of And Age Of Granitoid And Sandstone Clasts In Conglomerates Of The Paleocene To Upper Cretaceous Yakutat Group, Russell Fjord, Alaska, Alexander Dolcimascolo
Provenance Of And Age Of Granitoid And Sandstone Clasts In Conglomerates Of The Paleocene To Upper Cretaceous Yakutat Group, Russell Fjord, Alaska, Alexander Dolcimascolo
Honors Theses
The Paleocene to Upper Cretaceous Yakutat Group consists of a flysch facies. A conglomerate occurs in two places in Russell Fjord, and the composition and age of clasts bears on tectonic reconstructions. One site (#23) occurs in what is mapped as flysch and one in the mélange (#25), but the conglomerates are essentially identical. They contain clasts of sandstone, greenstone, limestone, marble, chert, and plutonic rocks that are clast supported, and interbedded with sandstones that contain coalified plant fragments. The maximum depositional age (MDA) of the U/Pb-dated zircons from the sandstone is 65.9 ± 1.8 Ma and 65.6 ± 2.2 …
Apatite Chemistry And Zoning In The Roseau Valley, Dominica, Lesser Antilles, Katherine Swager
Apatite Chemistry And Zoning In The Roseau Valley, Dominica, Lesser Antilles, Katherine Swager
Honors Theses
The island of Dominica is located in the center of the Lesser Antilles island arc. Located in the southwestern part of the island, the Roseau Valley contains a thick and complex stratigraphy of pyroclastic flows that terminate in the sea on the western side of the island near the capital of Roseau, likely originating from the Wotten Waven caldera, now partially capped by the Micotrin dome (Sigurdsson, 1972). We have dated several ignimbrite deposit using U-Th analyses of zircon rims. The ages of five deposits within the valley show polymodal distributions, suggesting multiple periods of crystallization (~6 ka - 250 …
Direction Of Lead Diffusion In Geological Samples Using Rutherford Backscattering Sepctrometry, Andrew Mccalmont
Direction Of Lead Diffusion In Geological Samples Using Rutherford Backscattering Sepctrometry, Andrew Mccalmont
Honors Theses
A Rutherford Backscattering (RBS) analysis experiment was performed on several pyrrhotite samples in order to understand their lead (Pb) diffusive properties and determine the diffusion coefficients for Pb into the sample. The pyrrhotite samples were prepared at Rensselaer Polytechnic Institute and were subsequently annealed for one to several days at temperatures on the order of 500–800℃. A 1.1–MV Pelletron Accelerator in the Union College Ion Beam Analysis Laboratory was used to produce beams of 3.3–MeV alpha particles. The beam of alpha particles collided with the samples and the backscattered alpha particles’ energies were detected using a silicon surface barrier detector. …
Exhumation Of The Baranof Schist In Whale Bay Alaska Determined Through Zircon Fission Track Dating, Kate Kaminski
Exhumation Of The Baranof Schist In Whale Bay Alaska Determined Through Zircon Fission Track Dating, Kate Kaminski
Honors Theses
During the Eocene in the North Pacific, the Kula, Farallon, and Pacific plates met in a trench-ridge-trench triple junction, bordered to the east by a continental margin along the edge of the North American plate. The flysch of the Chugach-Prince William terrane, a deformed accretionary complex, accreted onto this margin in the late Cretaceous to Paleocene. This terrane is framed to the north by the Border Ranges fault, a large strike-slip fault system that has accommodated northward movement of the Chugach-Prince William since the Eocene. One of the easternmost units of the Chugach-Prince William is the Baranof Schist on Baranof …
Glacial Lacustrine Records Of Holocene Climate Variations In The Tropical Peruvian Andes, Sasha Rothenberg
Glacial Lacustrine Records Of Holocene Climate Variations In The Tropical Peruvian Andes, Sasha Rothenberg
Honors Theses
Lake sediment cores taken from glacial lakes and wetlands are valuable proxies of glacial activity because they offer a continuous record of sediment input. Tropical alpine glaciers are especially sensitive to changes in precipitation and temperature, and thus the history of glaciation can be used in the reconstruction of past climates. Owing to a steep east-‐to-‐west moisture gradient across the Andes, glaciers in the eastern cordillera are more sensitive to changes in temperature whereas those in the drier, western, cordillera are more sensitive to changes in precipitation. Multiple lacustrine sediment cores were taken from two sites in the central Peruvian …
The History Of Mining In Cerro De Pasco And Heavy Metal Deposition In Lake Junin Peru, Erin M. Delman
The History Of Mining In Cerro De Pasco And Heavy Metal Deposition In Lake Junin Peru, Erin M. Delman
Honors Theses
Lake Junín covers 530-km2 and is located at 4,430-m in an intermontane basin between the eastern and western cordillera of the central Peruvian Andes. The lake sits between the large sulfide mining districts of La Oroya and Cerro de Pasco. Designated a National Reserve in 1974, Lake Junín drains northward to the Río San Juan, which joins the Río Mantaro within several kilometers of the lake. Dam construction by the Cerro de Pasco Copper Corporation on the Río Mantaro in 1932 caused the Río San Juan, the principal river draining Cerro de Pasco, to back up into the lake. Using …
Documenting The Anthropogenic Impact On Ballston Lake New York From A Short Core Using Stable Isotopes Of Carbon And Nitrogen And Trace Metals, Taylor S. Labrecque
Documenting The Anthropogenic Impact On Ballston Lake New York From A Short Core Using Stable Isotopes Of Carbon And Nitrogen And Trace Metals, Taylor S. Labrecque
Honors Theses
Ballston Lake occupies a portion of an avulsed channel of the Mohawk River between Schenectady and Saratoga Springs, New York. The lake is about 5 km long, generally less than 200m wide, ~8-15m deep, dimictic, with a catchment basin area of ~22km2. Long cores (>8 m) indicate that the lake formed ~13,000 cal yr BP. This study was undertaken to document recent environmental change recorded in the upper portion of sediment in Ballston Lake. Three sediment cores ~40 cm long were acquired from ~8 m water depth at the north end of Ballston Lake (42°57.101’N, 73°51.066’W), and were analyzed …
A Continuous Late Holocene Record Of Paleoclimate Change From Grinnell Lake Sediment Cores, Glacier National Park, Montana, Jonathan G. Griffith
A Continuous Late Holocene Record Of Paleoclimate Change From Grinnell Lake Sediment Cores, Glacier National Park, Montana, Jonathan G. Griffith
Honors Theses
Grinnell Lake is a glacially-fed alpine lake in the northern Rocky Mountains of Montana. Limnological parameters and radiocarbon ages from a ~1.17 -meter-long sediment core from Grinnell Lake provide a ~1,200 year-long climate record. The objective of this thesis is to develop a multi-proxy record of glaciation by distinguishing periods of positive and negative mass balance chronologically. Two overlapping sediment cores (1P-1B-1 and 1C-2B-1) were described, photographed, and sampled at 0.5 cm, 1 cm, and 5 cm intervals and analyzed for % organic carbon, % inorganic carbon, mineral composition, bulk density, biogenic silica, and clastic sediment flux. Glacial fluctuations were …
Detrital Zircon Fission Track Ages Of The Paleocene Orca Group Of Eastern Prince William Sound Near Cordova Alaska, Tyler M. Izykowski
Detrital Zircon Fission Track Ages Of The Paleocene Orca Group Of Eastern Prince William Sound Near Cordova Alaska, Tyler M. Izykowski
Honors Theses
The Prince William terrane is a major component of the Mesozoic-Tertiary accretionary complex of the North American Cordillera that is well exposed for ~2200 km in southern Alaska and is inferred to be one of the thickest accretionary complexes in the world. Detrital zircons from Prince William terrane record the thermal evolution and exhumation history of the accretionary wedge. Samples of the Paleocene-Eocene Orca Group of the Prince William terrane were analyzed using detrital zircon fission track techniques to understand the thermochronology of the region near Cordova. Six sandstones from the Orca Group and one sample of the Sheep Bay …
Geochemical And Petrographic Analysis Of Gore Mountain Garnets, Adirondacks Ny, Elizabeth R. Morgan
Geochemical And Petrographic Analysis Of Gore Mountain Garnets, Adirondacks Ny, Elizabeth R. Morgan
Honors Theses
The mine at Gore Mountain is famous for its giant garnets and long history of garnet abrasive production. This location, Warrensburg (Wall St.), and others were examined to attempt to better understand the petrogenesis of these remarkable rocks. Our studies have emphasized the geochemistry of bulk rocks and rock and mineral separates (122 analyses), thin section petrology, and thermodynamic modeling of mineral assemblages. At Gore Mtn. the ore has the assemblage hornblende-plagioclase-garnet-OPX-biotite, and formed over a ~2 m thick transition zone from a layered olivine corona gabbro, metamorphosed at granulite facies. Petrographically the delicate corona structures and fine-grained garnets were …
Petrologic Evidence For Mafic Recharge At Volcán Barú, Western Panama: Implications For A Late Pleistocene Sector Collapse, Shannon M. Brady
Petrologic Evidence For Mafic Recharge At Volcán Barú, Western Panama: Implications For A Late Pleistocene Sector Collapse, Shannon M. Brady
Honors Theses
The purpose of this study is to gain a better understanding of the petrologic conditions of the magma chamber beneath Volcán Barú in western Panama. Volcán Barú is an andesite stratovolcano that experienced a large sector collapse during the Late Pleistocene, which destabilized the southwestern flank of its edifice. Samples were taken from the cores of hummocks and megaclasts deposited as a result of this sector collapse, which are inferred to have been intact wall rock from the pre-collapse edifice. These samples range in composition from 51.8 to 61.7 wt. % SiO2 and have a geochemical signature that is consistent …