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Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand Dec 2020

Crustal Evolution Of The New England Appalachians: The Rise And Fall Of A Long-Lived Orogenic Plateau, Ian Hillenbrand

Masters Theses

The rise and demise of mountain belts, caused by growth, modification, or removal of the continental lithosphere are fundamental processes that influence almost all Earth systems. Understanding the nature, timing, and significance of active processes in the creation and evolution of modern mountain belts is challenged by a lack of middle crustal and lower crustal exposures. Analogues can be found in ancient orogens, whose deeply eroded roots offer a window into deeper processes, yet this record is complicated by overprinting events and complex deformational histories. Research presented herein constrains the tectonic history of multistage Appalachian Orogen, type locality of the …


Magnetite Mineralization Of The Hammondville Pluton: Poly-Phase Kiruna Type Iocg Magnetite-Apatite Deposits In The Lyon Mountain Granite, Phillip Geer Dec 2020

Magnetite Mineralization Of The Hammondville Pluton: Poly-Phase Kiruna Type Iocg Magnetite-Apatite Deposits In The Lyon Mountain Granite, Phillip Geer

Masters Theses

Recent mapping of the Eagle Lake Quadrangle, NY, coupled with whole-rock geochemistry and microscopy has offered insight into the petrogenesis of the magnetite-apatite deposits of the Hammondville mining district in the eastern Adirondack Mountains. This study provides insight into the magmatic history of the ca. 1060-1050 Ma Lyon Mountain Granite (Hammondville Pluton) which is intimately related to, and hosts the deposits in this area. Magnetite seams are commonly surrounded by well layered magnetite gneiss, which typically parallel the seams, although in some outcrops appear to be slightly truncated by them. Mineralization is generally concordant with the weak layering found throughout …


Plio-Pleistocene Paleoceonography Of The Ross Sea, Antarctica Based On Foraminifera From Iodp Sites U1523, U1522, And U1521, Julia Seidenstein Jul 2020

Plio-Pleistocene Paleoceonography Of The Ross Sea, Antarctica Based On Foraminifera From Iodp Sites U1523, U1522, And U1521, Julia Seidenstein

Masters Theses

The West Antarctic Ice Sheet (WAIS) is currently thinning and retreating because shifting oceanic currents are transporting warmer waters to the ice margin, which could lead to a collapse of the ice sheet and global sea level rise. International Ocean Discovery Program (IODP) Expedition 374 sailed to the Ross Sea in 2018 to study the history of the WAIS over the last 20 million years. Previous geologic drilling projects into Ross Sea sediments that record the history of the WAIS (DSDP Leg 28, RISP, MSSTS, Cape Roberts Drilling Project, ANDRILL), as well as modeling studies, show considerable variability of ice-sheet …


Seeing Through The Ottawan Overprint, Adirondack Mtns., Ny: Integrating Microstructural Analysis, Geothermobarometry, And In-Situ Monazite Petrochronology, Justin Mistikawy Apr 2020

Seeing Through The Ottawan Overprint, Adirondack Mtns., Ny: Integrating Microstructural Analysis, Geothermobarometry, And In-Situ Monazite Petrochronology, Justin Mistikawy

Masters Theses

Integrating field observation with petrochronology is critical for understanding the tectonometamorphic evolution of the North American Grenville Province. Despite methodological advances in geothermobarometry and geochronology, incorporating these data into larger models of the Adirondack Mountains remains particularly challenging due to the presence of multiple generations of deformation, primarily related to the ca. 1190 – 1140 Ma Shawinigan and ca. 1090 – 1020 Ma Ottawan Orogenies (McLelland et al.,2013). The Rock and Bear Ponds area is a dome of tight-to-isoclinally folded metapelites in structural contact with orthogneiss. Fold generations are orthogonal and partitioned such that the northern area is dominated by …


Threshold Processes And Stream Temperature Distribution In A Small New England Headwater Stream Catchment., Mitchell Isaacson Apr 2020

Threshold Processes And Stream Temperature Distribution In A Small New England Headwater Stream Catchment., Mitchell Isaacson

Masters Theses

Rising air temperature and decreasing stream flow trends are predicted to result in corresponding increases in stream temperatures. As a result, the future of ectothermic stream fishes, which rely on seasonal and spatial distributions of stream temperature for growth and survival, could be in jeopardy. Fortunately, contradicting stream temperature trends in forested headwater catchments suggest that non-climatic variables, such as baseflow indices and catchment geologic structure, may have an important confounding influence on the future of stream temperature. Most significantly, the annual stability of groundwater temperature has long been recognized as an important buffer between air and stream temperature. The …