Physical Sciences and Mathematics Commons^™

Investigating Mercer's Paradox: A 10be Chronology Of Moraines Deposited During The Last Glaciation At Soda Lake, Wind River Range, Wyoming, U.S.A., Lauren M. Woods

Electronic Theses and Dissertations

Here I use geomorphic mapping and ¹⁰Be surface-exposure dating to address the paradox that lies within the general understanding of the mechanisms driving ice-age climate and glacial cycles. The long-standing and widely accepted Murphy-Milankovitch hypothesis suggests glacial cycles are controlled by the local intensity of summer-time insolation. By this hypothesis, glacier maxima should be achieved at times of low insolation intensity and asynchronously between the polar hemispheres, a pattern which is inconsistent with the glacial geomorphic record. The ¹⁰Be chronology I have constructed of moraines at Soda Lake, Wind River Range, Wyoming, U.S.A. shows nine glacial advances to …

Arcmap Hydrology Toolset: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides guidance for performing hydrologic tasks using the Hydrology Toolset in ArcMap 10.x (ArcGIS Desktop). Covered here are an overview of the uses and limitations of the tools within the Hydrology Toolset, related tools from from additional ArcGIS toolsets, and step-by-step instructions for hydrologic workflows including digital elevation model (DEM) preparation, pit fill detection, "burning in" culverts for proper flow path routing, watershed and stream network delineation, and flow network statistics.

Total Station Field Surveying: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides step-by-step guidance for performing surveys of field sites using a total station unit (TSU) and connected handheld data collector and for downloading collected point data. WPES uses a Sokkia CX-series TSU and a data collector running Carlson SurvCE software. Minor differences in instrument set-up may arise if using a different TSU. Major differences in data collection procedures will occur if using a different data collection software.

Comparison Of Land Use And Flowslide Incidence In Palu Valley Following The 2018 Mw 7.5 Palu-Donggala Earthquake, Peta C. Fifield

Electronic Theses and Dissertations

The September 28 Mw 7.5 Palu-Donggala earthquake in Indonesia was the deadliest natural disaster in 2018. Five flowslides on the eastern side of Palu Valley, which were attributed to the substantial majority of deaths and economic losses in the region, occurred due to liquefaction of naturally dry alluvial deposits in gently sloping ground (2 to 6%). The requisite conditions for soil liquefaction are the presence of loose granular sediments and full saturation. Instigation of these catastrophic ground failures were linked to artificial saturation by an unlined agricultural irrigation canal. From a civil engineering perspective, the Palu ground failures on the …

Glaciology, Geomorphology Giant Roger Hooke Passes Away At 82, Division Of Marketing And Communications

General University of Maine Publications

Roger Hooke, beloved University of Maine mentor and researcher and giant in the fields of glaciology and geomorphology, died March 10 [2021] at the age of 82.

Hooke joined the School of Earth and Climate Sciences and Climate Change Institute in 2000 as a research professor and adviser. One of Hooke's interests during his time at UMaine involved examining what glacial landforms in Maine revealed about the Laurentide Ice Sheet.

Harold B. "Bud" Rollins (1 February 1939-9 January 2017), Daniel H. Sandweiss

Andean Past

This is an appreciation of the life and work of invertebrate paleontologist. Harold B. Rollins emphasizing his contributions to our understanding of ENSO.

Stream Dynamics In The Headwaters Of Post-Glacial Watershed Systems, Brett Gerard

Electronic Theses and Dissertations

This dissertation summarizes research examining watershed processes across Northern New England, with an emphasis on the Central and Coastal regions of Maine. The research presented here focuses on the linkages between watershed geomorphic conditions, climate, and surface flow regimes driving stream channel hydraulic conditions and bed dynamics governing channel geometry. The geologic and human history of the landscape provides the context in which earth surface processes are examined within the dominant physiographic settings in Maine to describe vulnerabilities to climate change. Results are summarized to support the development of sustainability solutions for forecasted watershed management problems by natural resource management …

Three-Dimensional Bedrock Channel Evolution With Smoothed Particle Hydrodynamics, Nick Richmond

Electronic Theses and Dissertations

Bedrock channels are responsible for balancing and communicating tectonic and climatic signals across landscapes, but it is difficult and dangerous to observe and measure the flows responsible for removing weakly-attached blocks of bedrock from the channel boundary. Consequently, quantitative descriptions of the dynamics of bedrock removal are scarce. Detailed numerical simulation of violent flows in three dimensions has been historically challenging due to technological limitations, but advances in computational fluid dynamics aided by high-performance computing have made it practical to generate approximate solutions to the governing equations of fluid dynamics. From these numerical solutions we gain detailed knowledge of the …

A Glacial History Of Roberts Massif, Central Transantarctic Mountains, Antarctica, Using Cosmogenic 3he, 10be, And 21ne Surface Exposure Ages, Alexandra M. Balter

Electronic Theses and Dissertations

Ice-free areas at high elevation in the central Transantarctic Mountains preserve moraines and drift deposits that delineate the former thickness and extent of the East Antarctic Ice Sheet (EAIS); cosmogenic exposure ages on these features indicate when the ice sheet was as or more extensive than today. Approximately 30 existing cosmogenic-nuclide exposure ages from scattered locations within these deposits suggest that some moraines and drift sheets are at least 5 Ma old. Those ages imply that the age range of these deposits may span warm periods during the Miocene and Pliocene, during which the EAIS is hypothesized to have been …

Utilizing Ground-Penetrating Radar In The Delineation And Cultural Resource Management Of Eroding Maine Coastal Shell Middens, Jacquelynn F. Miller

Electronic Theses and Dissertations

Shell middens along the Maine coast archive up to 5000 years of cultural and climatic change, but the record is continually and rapidly lost to the sea through climate-driven coastal erosion and sea-level rise. These sites were constructed by the ancestors of Maine Tribes, and are composed of centimeters to meters of clam (Mya arenaria) and/or oyster (Crassostrea virginica) shells, other faunal remains, and cultural materials. Shell middens record human interaction with the environment and early coastal occupation and adaptation. The faunal remains reflect paleoenvironmental conditions and the distribution of extinct and extant forage-species along the western Gulf of Maine. …

Glacial History Of The Tsagaan Gol- Potanin Glacier Valley, Altai Mountains, Mongolia, Mariah J. Radue

Electronic Theses and Dissertations

The last glacial termination (~19-11 ka) marks the end of the last ice age and the transition to modern interglacial conditions. The mechanisms that triggered deglaciation are unresolved. Various hypotheses for deglacial warming involve changes in Earth’s orbit, an 80-ppm increase in atmospheric CO­₂, a ‘bipolar seesaw’ in oceanic-heat redistribution, and shifting wind belts. Here, I present a ¹⁰Be surface-exposure chronology for a system of glacial landforms in the Tsagaan Gol-Potanin Glacier valley in the Mongolian Altai (49°N, 88°E) to determine the nature of the termination in interior Asia. Located near the center of Earth’s largest continent, …

Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston

Electronic Theses and Dissertations

Dam removals from the Penobscot River in Maine restored access to freshwater habitat critical for the life cycle of endangered shortnose sturgeon. Prior to the dam removals, shortnose sturgeon spawning activity had not been documented. Instead, evidence suggested that individuals emigrated from the Penobscot River to spawn in the Kennebec complex, 140 km away. A central question of this thesis was whether spawning activity would commence in the first two years following dam removal. Consistent with pre-dam removal movement patterns determined using acoustic telemetry, the majority (78%) of tagged individuals emigrated from the Penobscot River at some point over the …

Sediment Accumulations Patterns In The Damariscotta River Estuary, Emily A. Chandler

Electronic Theses and Dissertations

The tidally dominated Damariscotta River estuary is located on the south-central Maine coast. The elongate, north-south orientation of the estuary is characteristic of the indented shoreline in this region and a consequence of the bedrock structural framework, comprised of Paleozoic high-grade metasedimentary rocks. Pegmatite sills form bedrock constriction points that divide the estuary into seven distinct basins. The narrow, bending geometry and sill and basin morphology impact the distribution of sediment within the estuary and the hydrodynamics of the system. This study employs multibeam bathymetry surveys, sediment grab samples and radionuclide analysis (²¹⁰Pb and ¹³⁷Cs) of sediment …

Topographic Signatures Of Geodynamics, Samuel G. Roy

Electronic Theses and Dissertations

The surface of the Earth retains an imperfect memory of the diverse geodynamic, climatic, and surface transport processes that cooperatively drive the evolution of Earth. In this thesis I explore the potential of using topographic analysis and landscape evolution models to unlock past and/or present evidence for geodynamic activity. I explore the potential isolated effects of geodynamics on landscape evolution, particularly focusing on two byproducts of tectonic strain: rock displacement and damage. Field evidence supports a strong correlation between rock damage and erodibility, and a numerical sensitivity analysis supports the hypothesis that an order of magnitude weakening in rock, well …

Coupled Deformation And Metamorphism, Fabric Development, Rheological Evolution And Strain Localization, Scott E. Johnson

University of Maine Office of Research Administration: Grant Reports

When Earth's tectonic plates interact with one another the rocks that comprise them are deformed, commonly forming great mountain chains. During this deformation, the minerals that make up the rocks can become spatially or crystallographically aligned to form a fabric. The development of rock fabric is a primary factor affecting the strength, or rheological evolution of deforming rocks. Fabric development commonly involves coupling of both physical and chemical processes. For example, crenulation cleavage is the most common type of fabric in multiply deformed rocks, and its formation leads to extreme mineral segregation and rheological anisotropy. It is also commonly associated …

Development In The Gulf Of Maine: Avoiding Geohazards And Embracing Opportunities, Laura L. Brothers, Joseph T. Kelley, Melissa Landon Maynard, Daniel F. Belknap, Stephen M. Dickson

Maine Policy Review

Mapping for marine-spatial planning is crucial if Maine is to safely develop its offshore resources, espe­cially wind and tidal energy. The authors focus on shallow natural gas (methane) deposits, an important and widespread geohazard in Maine’s seafloor. They describe the origin, occur­rence, and identification of natural gas in Maine’s seafloor; explain the hazards associated with these deposits and how to map them; and discuss what Maine can learn from European nations that have already developed their offshore wind resources. Because the U.S. gives states a central role in coastal management, Maine has the chance to be proactive in delineating coastal …

Three-Dimensional Modeling Of Continental Subduction And The Evolution Of Ultra High Pressure Metamorphism, Peter O. Koons

University of Maine Office of Research Administration: Grant Reports

This project investigates driving forces and material behavior associated with continental subduction and ultra high-pressure metamorphism through an integration of numerical modeling of continental subduction and structural/petrological evolution of the material caught in the collision. The natural ultra high-pressure and high-pressure assemblages of the Western Gneiss of Norway provide rheological, geometric and geochronological information for the modeling, while the active obliquely convergent plate boundary of central New Zealand serves as a modern analog of a collision-subduction transition. Continental subduction zones represent regions where the crust-mantle interaction changes from nearly horizontal to dominantly vertical, accentuating the competing influences of body and …

Numerical Facility In Geodynamics, Peter O. Koons, Scott Johnson, Phaedra Upton

University of Maine Office of Research Administration: Grant Reports

Support from this grant will contribute to the construction of a numerical facility for Geodynamical Modeling at the University of Maine to investigate mechanical and thermal problems arising in lithosphere and mantle deformation. Specifically, the PI's will examine the degree of coupling among atmospheric and tectonic processes through construction of three-dimensional models conditioned by observations from the active tectonic regions of eastern Tibet, New Zealand and southeast Alaska. In related research, the PI's are examining the necessary conditions for formation and exhumation of ultra-high pressure metamorphism terrains during plate convergence. The overriding objective of the numerical facility is to provide …

Thermal And Mechanical Effects Of A Shallow Asthenosphere In The Acadian Orogen: An Investigation Through Numerical Modeling, Lucy E. Brown

Electronic Theses and Dissertations

A high-temperature region associated with Acadian deformation extends 200 km through north-central New England. The scale of this heat source is investigated in order to better understand the rheology and mechanics of deforming orogens. In central Maine, on the boundary of the high-temperature region, isograds in pelitic rocks are normal to the accretionary structures and record a steep northeast-southwest thermal gradient. The isogradic sequence, geobarometry, and the mineral assemblages indicate low-pressure, high-temperature metamorphism, moderately low pressures of 3 kbar, and temperatures ranging from 600º to 450ºC over a 10 km region. The spacing between these isograds and the temperature at …

Coastal Change And Beach Ridges Along The Northwest Coast Of Peru: Image And Gis Analysisof The Chira, Piura, And Colán Beach-Ridge Plains, Stacy Shafer Rogers, Daniel H. Sandweiss, Kirk A. Maasch, Daniel F. Belknap, Peggy Agouris

Anthropology Faculty Scholarship

Since approximately 5200 cal yrs BP, five sets of eight to nine beach ridges were built and preserved along the northwestern Peruvian coastal desert (3o30'S-9oS). Potential ridge-building mechanisms in the hyper-arid environment of northwest Peru include El Nifio floods and storms, seismic activity, and sea-level change, as well as more gradualc limate changes that affectedc oastal morphologyI. mage processinga nd GeographicI nformationS ystem (GIS) methods were used to analyze aerial photographs and measure historic coastal patterns along three beach-ridge plains over a 37-year time period. Coastal features were digitized from image mosaics of each ridge plain at different time intervals …

Relationships Between Stream Geomorphology And Fish Community Structure And Diversity In Maine, Emily Gaenzle

Electronic Theses and Dissertations

Predicting patterns in species distribution and abundance for resource management and conservation is a major focus of applied ecology. The primary objective of this study was to determine if there is a predictable relationship between stream geomorphology and fish community structure, native species richness, and native salmonid abundance in Maine. Specifically, I examined relationships between fish assemblages and geomorphic stream types, as delineated by the Rosgen classification system (Rosgen 1996). Fifty-three stream reaches in Maine were classified, and fish communities within the reaches were characterized using backpack electrofishing. Species richness was lowest in A-type streams (i.e., steep, entrenched, confined), which …

Surficial Geology And Geomorphology Of The Western Olympus Range, Antarctica: Implications For Ice-Sheet History, Brett Vandenheuvel

Electronic Theses and Dissertations

A widespread erosion surface passes across bedrock and sedimentary deposits in the western Dry Valleys sector of the Transantarctic Mountains (TAM), southern Victoria Land, Antarctica. The surface includes stoss-and-lee slopes, channels, potholes, scoured basins, and corrugated bedrock. These features have been taken to represent subglacial meltwater erosion beneath a greatly expanded East Antarctic Ice Sheet (EAIS) in the mid-Miocene (Denton et al. 1984, Marchant et al. 1993a). Sedimentary deposits that are typically associated with ice-sheet wastage, such as outwash, are not present on the erosion surface. The lack of these deposits indicates that the expanded ice-sheet postulated to be responsible …

Late Maritime Woodland (Ceramic) And Paleoindian End Scrapers: Stone Tool Technology, Pamela J. Dickinson

Electronic Theses and Dissertations

Archaeologists tend to view lithic assemblages from a predominately morphological perspective, stressing the importance of the fluted point as the defining characteristic of the Paleoindian culture period (ca. 10,000 years B.P.). In applying such a characteristic, Paleoindian sites have been identified throughout the Northeast. However, there are no identified Paleoindian sites in New Brunswick. It is possible that some sites are largely ignored or thought to lack a Paleoindian component if a fluted point is absent. If such sites are being overlooked, then the database may under represent the Paleoindian culture period. Spurred end scrapers commonly occur in known Paleoindian …

Discussion Of: Lisa E. Wells, 1996. The Santa Beach Ridge Complex, Journal Of Coastal Research, 12(1), 1-17, Daniel H. Sandweiss, Kirk A. Maasch, Daniel F. Belknap, J. B. Richardson Iii, H. B. Rollins

Anthropology Faculty Scholarship

No abstract provided.

The Dominion Range Ice Core, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Localized-accumulation basins in the Transantarctic Mountains contain sites yielding ice-cores that provide highly detailed (seasonal to annual resolution, depending upon depth),several-thousand-year records of glacial history, climatic change, volcanic activity, and atmospheric chemistry. The scientific attraction of these sites, first, their geographic location with respect to other ice-core studies (which are most commonly recovered from inland sectors of the antarctic ice sheet)and second, the fact that Transantarctic Mountain sites are more directly comparable to glacial geologic records because the latter are usually based on studies in these mountains. Although the ice-core records from these sites cover shorter periods than glacial geologic …

Glaciochemical Studies And Estimated Net Mass Balances For Rennick Glacier Area, Antarctica, Boyd Allen Iii, Paul Andrew Mayewski, W. Berry Lyons, Mary Jo Spencer

Earth Science Faculty Scholarship

Two snow and ice cores from the Rennick Glacier area, Antarctica (study area center point lat 71° 15' S, long 162° 30' E) were analyzed for the chemical species: chloride, sodium, reactive silicate, sulfate and nitrate. Core E1O (6.35 m) was taken from Evans Névé, a large accumulation basin at the head of Rennick Glacier. Core M1 (4.35 m) was extracted from the accumulation zone on the central plateau of the Morozumi Range, a small mountain massif bordering Rennick Glacier. Cores E1O and M1 span the time periods from 1929 to 1981 and from 1971 to 1981, respectively, as dated …

Morphology And Dynamics Of The Rock Glaciers In Southern Victoria Land, Antarctica, Jon M. Hassinger, Paul Andrew Mayewski

Earth Science Faculty Scholarship

A baseline study of rock glaciers located in the ice-free valleys of southern Victoria Land, Antarctica, was performed in order to determine their usefulness as proxy tools in studies of climatic change. The distribution of the 32 rock glaciers identified in this analysis is principally attributed to site-specific controls including proximity to localized moisture sources and low ambient site temperature controlled by elevation, orientation, and topographic shading. The relative activity of rock glaciers and their vertical velocity profiles are inferred from termini morphology. Thirty-eight percent of the rock glaciers are stagnant, 41% show velocity decreasing rapidly with depth, and velocity …

Ice Mass Fluctuations In Northernvictoria Land, Paul Andrew Mayewski

Earth Science Faculty Scholarship

[From the introduction] Rennick Glacier is one of the major ice drainages for the northern Victoria Land sector of East Antarctica. Unlike glaciers farther south along the Transantarctic Mountains, Rennick Glacier does not drain into the Ross Ice Shelf but flows directly into a seasonally ice-covered ocean. Therefore, current fluctuations of this glacier are unhampered by the dampening effects of the Ross Ice Shelf. The primary controls on the activity of this glacier and others in this region are mass balance and sea level.

Geochemical And Glacio-Geomorphic Implications Of Basalt Weathering In The Queen Maud Mountains, Antarctica, R. W. Talkington, Paul Andrew Mayewski, H. E. Gaudette

Earth Science Faculty Scholarship

Summary. The weathering of a suite of basalt clasts. that have been transported by mass wasting downslope in the Cumulus Hills region of the Queen Maud Mountains. Antarctica. is examined from both geochemical and glacio-geomorphic viewpoints. Chemical weathering. predominantly oxidation and hydration. increases in severity from clast core to rim for the suite. These weathering processes and concomitant formation of a weathering rind are suggested to be an accumulative process. culminating in the disaggregation of the rock due in part both to the chemical breakdown of the interstitial and intersertal basaltic glass and to physical weathering processes. Mass wasting rates …

Himalayan And Trans-Himalayan Glacier Fluctuations Since Ad 1812, Paul Andrew Mayewski, Peter A. Jeschke

Earth Science Faculty Scholarship

Historical records of the fluctuations of glaciers in the Himalayas and Trans-Himalayas date back to the early 19th century. Local and regional syntheses of 112 of these fluctuation records are presented in this study. The local syntheses deal with fluctuations of glaciers in Kanchenjunga-Everest, Garwhal, Lahaul-Spiti, Kolahoi, Nanga Parbat, Karakoram (north and south sides), Rakaposhi-Haramosh, Batura Mustagh, and Khunjerab-Ghujerab. Regional syntheses deal with the composite record and the differentiation of records by glacier type (longitudinal versus transverse) and regional setting (Himalayan versus Trans-Himalayan). In a gross regional sense Himalayan and Trans-Himalayan glaciers have been in a general state of retreat …