Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Boreal (2)
- Kilauea (2)
- Michigan Tech Research Institute (2)
- Remote Sensing (2)
- Remote sensing (2)
-
- Archean (1)
- BIF (1)
- Batholith (1)
- Bog (1)
- Carbon (1)
- Chlorophyll (1)
- Classification (1)
- Cliftonite (1)
- Climate change (1)
- Conduit Processes (1)
- Critical load (1)
- Deformation (1)
- Detroit River (1)
- Diamond (1)
- Diffuse Degassing (1)
- Distributed model (1)
- Drylands (1)
- Event Detection (1)
- Fault (1)
- Fault slip (1)
- Folding (1)
- Freshwater Lakes (1)
- Full Waveform Moment Tensor Inversion (1)
- GSSHA (1)
- Geology (1)
- Publication
- Publication Type
Articles 1 - 16 of 16
Full-Text Articles in Entire DC Network
Regional Scale Dryland Vegetation Classification With An Integrated Lidar-Hyperspectral Approach, Hamid Dashti, Andrew Poley, Nancy Glenn, Nayani Ilangakoon, Lucas Spaete, Dar Roberts, Et. Al.
Regional Scale Dryland Vegetation Classification With An Integrated Lidar-Hyperspectral Approach, Hamid Dashti, Andrew Poley, Nancy Glenn, Nayani Ilangakoon, Lucas Spaete, Dar Roberts, Et. Al.
Michigan Tech Publications
The sparse canopy cover and large contribution of bright background soil, along with the heterogeneous vegetation types in close proximity, are common challenges for mapping dryland vegetation with remote sensing. Consequently, the results of a single classification algorithm or one type of sensor to characterize dryland vegetation typically show low accuracy and lack robustness. In our study, we improved classification accuracy in a semi-arid ecosystem based on the use of vegetation optical (hyperspectral) and structural (lidar) information combined with the environmental characteristics of the landscape. To accomplish this goal, we used both spectral angle mapper (SAM) and multiple endmember spectral …
Experimental Nitrogen Addition Alters Structure And Function Of A Boreal Bog: Critical Load And Thresholds Revealed, R. Kelman Wieder, Dale H. Vitt, Melanie A. Vile, Jeremy A. Graham, Jeremy A. Hartsock, Hope Fillingim, Et Al.
Experimental Nitrogen Addition Alters Structure And Function Of A Boreal Bog: Critical Load And Thresholds Revealed, R. Kelman Wieder, Dale H. Vitt, Melanie A. Vile, Jeremy A. Graham, Jeremy A. Hartsock, Hope Fillingim, Et Al.
Michigan Tech Publications
Bogs and fens cover 6% and 21%, respectively, of the 140,329 km2 Oil Sands Administrative Area in northern Alberta. Development of the oil sands has led to increasing atmospheric N deposition, with values as high as 17 kg N.ha-1yr-1; regional background deposition is N.ha-1yr-1. Bogs, being ombrotrophic, may be especially susceptible to increasing N deposition. To examine responses to N deposition, over five years, we experimentally applied N (as NH4NO3) to a bog near Mariana Lake, Alberta, unaffected by oil sands activities, at …
Natural Graphite Cuboids, Andrey Korsakov, Olga V. Rezvukhina, John Jaszczak, Dmitriy I. Rezvukhin, Denis Mikhailenko
Natural Graphite Cuboids, Andrey Korsakov, Olga V. Rezvukhina, John Jaszczak, Dmitriy I. Rezvukhin, Denis Mikhailenko
Department of Physics Publications
Graphite cuboids are abundant in ultrahigh-pressure metamorphic rocks and are generally interpreted as products of partial or complete graphitization of pre-existing diamonds. The understanding of the graphite cuboid structure and its formation mechanisms is still very limited compared to nanotubes, cones, and other carbon morphologies. This paper is devoted to the natural occurrences of graphite cuboids in several metamorphic and magmatic rocks, including diamondiferous metamorphic assemblages. The studied cuboids are polycrystalline aggregates composed either of numerous smaller graphite cuboids with smooth surfaces or graphite flakes radiating from a common center. Silicates, oxides, and sulphides are abundant in all the samples …
Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze
Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze
Department of Geological and Mining Engineering and Sciences Publications
The Enguri dam and water reservoir, nested in the southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that affect a subaerial area of 1.2 km2. The head scarp affects the Jvari–Khaishi–Mestia main road with offsets of man-made features that indicate slip rates of 2–9 cm yr−1. Static, pseudostatic and Newmark analyses, based on field and seismological data, suggest different unstable …
Application Of A Distributed Hydrologic Model For The Analysis Of Land Use Change In Kedougou, Senegal, Francisco Perez
Application Of A Distributed Hydrologic Model For The Analysis Of Land Use Change In Kedougou, Senegal, Francisco Perez
Dissertations, Master's Theses and Master's Reports
West Africa has experienced extensive land use/land cover (LULC) change since the Sahel drought of the 1970s and 80s. Demographic changes, rapid urbanization, and other anthropogenic impacts on land cover in West Africa have potentially altered hydrological regimes. This work was undertaken while I served as a Peace Corps Volunteer in the Kedougou region of Senegal, an area that has experienced significant and rapid infrastructural improvements and urbanization since the early 2000s. The Gambia River flows near Kedougou, where flooding is an extensive problem, making access and livelihood practices difficult during the rainy season. Changes in climate and land use …
Characterizing Freshwater Phytoplankton Dynamics With Electro-Optical Remote Sensing, Michael Sayers
Characterizing Freshwater Phytoplankton Dynamics With Electro-Optical Remote Sensing, Michael Sayers
Dissertations, Master's Theses and Master's Reports
Freshwater lakes are an important component contributing to ecosystem health and biodiversity on local, regional, and global scales. And while lakes only represent <5% of the global surface area, they are often very productive systems which contribute significantly to carbon cycling dynamics and freshwater fish production on a number of spatial scales. Due to the remote location and sheer size of some of these lakes it has proven difficult to adequately document changes in water quality. Significant challenges exist to adequately monitor water quality, and in particular phytoplankton dynamics, over large spatial and temporal scales using traditional in situ methods. Satellite electro-optical remote sensing offers a potential tool to provide better characterization of phytoplankton dynamics for a variety of freshwater systems. This work resulted in an approach to quantify global summer phytoplankton abundance using a newly developed remote sensing derived chlorophyll-a product. This product was also used in conjunction with a newly created carbon fixation model to assess global freshwater phytoplankton production which provided new insights into the role freshwater systems play in the …
Magnetic Characterization Of Iron Formations From Drill Cores Near Iron Mountain, Michigan, Adren Rigdon
Magnetic Characterization Of Iron Formations From Drill Cores Near Iron Mountain, Michigan, Adren Rigdon
Dissertations, Master's Theses and Master's Reports
The magnetic properties of the ~1.88 Ga Vulcan Iron Formation and Felch Formation were investigated from samples taken from three drill cores through the Felch Trough, north of Iron Mountain, MI. The conducted analyses included measurements of natural remanent magnetization, magnetic hysteresis, first order reversal curves, magnetic anisotropy, scanning electron microscopy, and electron dispersive spectroscopy. The data is compared to the results of a previous magnetic characterization study conducted on surface outcrop samples on two members of the Vulcan formation, the Curry and Traders members, near Iron Mountain, MI. Two distinct members of the Vulcan Formation were identified in the …
Keweenaw Fault Geometry And Slip Kinematics - Bête Grise Bay, Keweenaw Peninsula, Michigan, Colin Tyrrell
Keweenaw Fault Geometry And Slip Kinematics - Bête Grise Bay, Keweenaw Peninsula, Michigan, Colin Tyrrell
Dissertations, Master's Theses and Master's Reports
The Keweenaw Fault (KF) has been interpreted as a rift-bounding normal fault along the southern margin of the Midcontinent Rift System; later inverted into a reverse fault by a tectonic compression event. The fault trends NNE to NE for most of its trace but curves clockwise to ESE along the Bête Grise Bay area in Michigan’s Keweenaw Peninsula. U.S. Geological Survey maps depict the KF along Bête Grise Bay as a continuous thrust that follows a sinuous contact between Portage Lake Volcanics (PLV) and Jacobsville Sandstone (JS). New fieldwork reveals a left-stepping en echelon system of ESE-trending faults connected by …
Seismic Signals And Sources At Fuego Volcano, Guatemala During January 2012, Kyle Brill
Seismic Signals And Sources At Fuego Volcano, Guatemala During January 2012, Kyle Brill
Dissertations, Master's Theses and Master's Reports
Forecasting volcanic activity is challenging. The task is uniquely difficult at open vent volcanoes which present persistent low-level eruptions over long periods of time. Volcán de Fuego in Guatemala began its current eruptive episode in 1999. Fuego exhibited “background” levels of activity during January of 2012 when we installed a temporary monitoring network to produce a detailed baseline description of the volcano’s behavior. We accomplish this using data from two low-frequency microphone arrays, nine broadband (50 Hz to 30 second flat response) seismic stations, and visual time-lapse imagery collected over a period of ten days. We begin with a detailed …
Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa
Linking Historical, Field, And Satellite Data To Determine The Relationship Between Gas Emissions And Vegetation Change In The Puhimau Geothermal Area East Rift Zone Kilauea, Hawaii, Christie Torres Rosa
Dissertations, Master's Theses and Master's Reports
The Puhimau geothermal area, located near the summit of the Kilauea volcano, Hawaii, has been suggested to represent a ‘window’ into the East Rift Zone. The quantification of CO2 and H2S soil gas emissions improves our understanding of its gas emission mode- including total emission and spatial distribution and contribute to a more accurate estimation of total CO2 and H2S in the thermal area – and how these gas emissions relate to observed vegetation health from satellite data. The total emission of CO2 and H2S was interpolated by the sequential Gaussian …
The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk
The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk
Dissertations, Master's Theses and Master's Reports
The Southern Complex is part of the Archean Superior Province in the Upper Peninsula of Michigan and includes a batholithic sized body of Archean high-K megacrystic granitoid rocks informally called the Bell Creek granite. U-Pb zircon ages of the granitoid from previous studies suggest an emplacement age of ~2.6 Ga (Tinkham, 1997). Based on those ages the Bell Creek granite formed around the Archean-Proterozoic transition. This transition is a crucial time period in Earth’s history for crustal growth because of the onset of subduction and increased sedimentary environments at the end of the Archean (Taylor and McLennan, 1995). In this …
Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas
Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas
Dissertations, Master's Theses and Master's Reports
One of the most prominent structural features associated with the ~1.1 Ga Midcontinent Rift (MCR) system is the >350 km long Keweenaw Fault that bisects the Keweenaw Peninsula, separating the MCR-related Portage Lake Volcanics (PLV) and the younger Jacobsville Sandstone (JS). The fault trend is NE-NNE over most of its length, but changes to an easterly direction along the shore of Bête Grise Bay near the end of the peninsula. Conventionally, the Keweenaw Fault has been considered to be a continuous reverse (dip-slip) fault formed by inversion of an original rift-bounding normal fault during the Grenville Orogeny. However, recent mapping …
Testing The Use Of Vegetation Indices As Indicators Of Pre-Eruptive Volcanic Unrest At Kilauea Volcano, Hawaii, Quelyn Bekkering
Testing The Use Of Vegetation Indices As Indicators Of Pre-Eruptive Volcanic Unrest At Kilauea Volcano, Hawaii, Quelyn Bekkering
Dissertations, Master's Theses and Master's Reports
Satellite remote sensing has become an integral part of pre-eruptive and long-term volcano monitoring due to its low cost, spatial and temporal coverage, and time-series analysis capabilities. Pre-eruptive unrest at volcanoes can include increased fluxes of heat and volcanic gases, which can be manifested either directly (e.g., the appearance of thermal anomalies or fumaroles) or indirectly (e.g., through impacts on vegetation health and extent). We are evaluating the use of novel, high spatial and temporal resolution data from the Planet Labs cubesat constellation to monitor changes in vegetation related to volcanic unrest. We present results from a study of key …
Spatial And Temporal Distribution Of Hydrothermal Minerals And Sources Of Hydrothermal Fluids Inferred From Light Stable Isotopes, Keweenaw Peninsula Native Copper District, Michigan, Thomas Bodden
Dissertations, Master's Theses and Master's Reports
Hydrothermal native copper deposits are hosted by Mesoproterozoic Midcontinent Rift-filling volcanic and sedimentary rocks in Michigan’s Keweenaw Peninsula. The genesis of the native copper deposits has been a point of interest since their discovery. Native copper and associated mineral assemblages vary temporally and spatially. A refined mineral paragenesis is presented and used as the basis to spatially compare mineral assemblages as it is essential that spatial comparison involve only minerals that are temporally/genetically, related to each other. The main-stage minerals associated with precipitation of native copper are spatially zoned. The higher-grade zones correspond to the area of native copper deposits …
Assessing The Spatial And Temporal Variability Of The Detroit River And Harmful Algal Blooms In Western Lake Erie, Angela W. Yu
Assessing The Spatial And Temporal Variability Of The Detroit River And Harmful Algal Blooms In Western Lake Erie, Angela W. Yu
Dissertations, Master's Theses and Master's Reports
Despite efforts to reduce the occurrence of harmful algal blooms (HABs) in western Lake Erie, blooms recur annually due to agricultural runoff, storms with high winds and heavy rains, and weak lake circulation patterns. The influence from river inputs on the spatial and temporal characteristics of HABs remains relatively unknown. The Detroit River, which contributes about 80% of the basin's total inflow can have a large influence on the spatial and temporal distribution of the bloom. To understand this, optically classified imagery, in situ water measurements, and meteorological and river discharge observations were compiled and synthesized to examine the spatiotemporal …
Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp
Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp
Dissertations, Master's Theses and Master's Reports
Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …