Thesis (M.A.)--University of Montana, 2008. / Title from title screen. Description based on contents viewed Aug. 7, 2008. Includes bibliographical references (p. 110-123).

Migmatites are a common rock type in the Adirondack Mountains, NY. We analyzed a single sample of biotite-garnet-sillimanite paragneiss with foliation parallel leucosome along Route 22 south of Whitehall, NY in order to determine the timing of melting using both in-situ monazite and zircon U/Pb geochronology from the restite and leucosome layers of the same rock. Monazite was analyzed via in-situ EMPA on the Ultrachron microprobe at the University of Massachusetts. Zircon was analyzed via LA-ICP-MS (in-situ and mounted mineral separates) at the LaserChron Center. Monazite analyses from the restite yielded six compositionally distinct populations with dates of 1178 ± 16, 1139 ± 4, 1064 ± 6, 1049 ± 4, 1030 ± 5, and 1004 ± 10 Ma. Yttrium and heavy REEs decrease in monazite in two steps: one dramatic drop from ca. 1150 to 1065 Ma and another between ca. 1065 and 1050, interpreted to reflect two periods of garnet growth and melting. Analyses from the restite zircon separate yielded a significant single peak near 1050 Ma. These zircon grains exhibit fir-tree sector zoning texture which is interpreted to indicate crystallization from melt. Monazite from leucosome yielded a unimodal population at ca. 1050 Ma, however, backscatter images document alteration of monazite to apatite on the edges of the grains, and abundant uranothorite inclusions. Leucosome zircon analyses yielded a ca. 1150 Ma population from cores and a 1050 Ma population from rims. Cathodoluminescence imaging reveals that the zircon rims have textures indicative of fluid alteration. The data are consistent with these rocks undergoing two periods of melting. The first event at ca. 1150 Ma may have involved a non-garnet producing melting reaction, such as muscovite dehydration-melting. The second event at 1065 Ma involved significant garnet growth, interpreted to represent biotite dehydration-melting. Subsequently, the rocks underwent hydrothermal alteration at 1050 Ma. Monazite grains with dates at 1030 ± 5 and 1004 ± 10 Ma have higher yttrium concentrations suggesting garnet breakdown and monazite growth during decompression and retrograde metamorphism. A combination of monazite and zircon dating techniques from each compositional layer is necessary to constrain leucosome-restite relationships and to accurately interpret the timing of melting from migmatites that have experienced multiple phases of melting.

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 an earlier episode of D2 deformation and an E-W S2 fabric and the southern by D3 deformation and a N-S S3 fabric. Observed assemblages include Qtz + Pl + Kfs + Bt + Sil + Grt + Gr ± Py ± Mnz ± Zr in metapelite and Hbl + Pl + Grt + Qtz + CPx ± Ilm in metagabbro. Metapelitic garnet is anhedral and overgrows a strongly transposed S1 fabric. A population of small high-Y monazite cores are associated with S1 and yield a mean weighted date of 1174 ± 5 Ma. Monazite observed in S2-defining phases and matrix have very high-Y & HREE cores that yield dates of 1068 ± 7 Ma and are surrounded by low-Y & HREE mantles (1048 ± 4 Ma) with irregular high-Y rims (1023 ± 6 Ma). These data suggest garnet growth followed the transposition of a strong Shawinigan S1 fabric during D2 and D3 folding events, ca. 1090 – 1070 Ma. The timing of this shortening is interpreted to coincide with the early Ottawan Orogeny, ca. 1090 – 1050 Ma. Geothermobarometric calculations of S2-associated phases constrains peak metamorphic conditions to 700 – 750 ± 50 °C and 6.5-7.5 ± 1 kbar; these data are well in agreement with those reported in multiple studies, thereby suggesting that regional PT calculations reflect Ottawan tectonometamorphic conditions (Bohlen et al., 1985; Spear & Markussen, 1997; Storm & Spear, 2005). High-Y & HREE rims are also observed and interpreted to reflect garnet breakdown ca. 1050 – 990 Ma during decompression and orogenic collapse, which has become increasingly reported in the eastern Adirondack Mountains over the last decade (Wong et al., 2012; Chiarenzelli et al., 2017; Regan et al., 2019; Williams et al., 2019). The Mesoproterozoic metapelite of the Rock and Bear Ponds area record an intense polydeformational history and therefore provide a valuable window into episodic middle-to-lower crustal deformation and metamorphism. The integration of focused microstructural observation with geothermobarometric and timing constraints has provided much insight into the structural evolution of the Adirondack Mountains. 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 an earlier episode of D2 deformation and an E-W S2 fabric and the southern by D3 deformation and a N-S S3 fabric. Observed assemblages include Qtz + Pl + Kfs + Bt + Sil + Grt + Gr ± Py ± Mnz ± Zr in metapelite and Hbl + Pl + Grt + Qtz + CPx ± Ilm in metagabbro. Metapelitic garnet is anhedral and overgrows a strongly transposed S1 fabric. A population of small high-Y monazite cores are associated with S1 and yield a mean weighted date of 1174 ± 5 Ma. Monazite observed in S2-defining phases and matrix have very high-Y & HREE cores that yield dates of 1068 ± 7 Ma and are surrounded by low-Y & HREE mantles (1048 ± 4 Ma) with irregular high-Y rims (1023 ± 6 Ma). These data suggest garnet growth followed the transposition of a strong Shawinigan S1 fabric during D2 and D3 folding events, ca. 1090 – 1070 Ma. The timing of this shortening is interpreted to coincide with the early Ottawan Orogeny, ca. 1090 – 1050 Ma. Geothermobarometric calculations of S2-associated phases constrains peak metamorphic conditions to 700 – 750 ± 50 °C and 6.5-7.5 ± 1 kbar; these data are well in agreement with those reported in multiple studies, thereby suggesting that regional PT calculations reflect Ottawan tectonometamorphic conditions (Bohlen et al., 1985; Spear & Markussen, 1997; Storm & Spear, 2005). High-Y & HREE rims are also observed and interpreted to reflect garnet breakdown ca. 1050 – 990 Ma during decompression and orogenic collapse, which has become increasingly reported in the eastern Adirondack Mountains over the last decade (Wong et al., 2012; Chiarenzelli et al., 2017; Regan et al., 2019; Williams et al., 2019). The Mesoproterozoic metapelite of the Rock and Bear Ponds area record an intense polydeformational history and therefore provide a valuable window into episodic middle-to-lower crustal deformation and metamorphism. The integration of focused microstructural observation with geothermobarometric and timing constraints has provided much insight into the structural evolution of the Adirondack Mountains.

The Speculator Sheet and the Wells-Tenantville Sill are intruded into the Rooster Hill/Little Moose Mountain Formations in the southern Adirondacks. The Wells Sill consists of a medium-grained gabbro forming the top and basal layers, and an inner core of anorthositic gabbro rimmed by a fine-grained chill margin called the Tenantville facies. The Speculator Sheet consists of gabbroic anorthosite and has a mafic lower margin due to gravitational settling of mafic phases. Plagioclase and pyroxene compositions suggest that the Wells gabbro is distinct from the rest of the sills and is related to the Oregon Dome. Whole rock data show that the gabbroic anorthosite and the rocks of the Thirteenth Lake Dome have a differentiation trend of minor iron enrichment, while the Wells gabbro, Oregon Dome and Snowy Mountain Dome have a trend of more extreme iron enrichment. Field evidence indicates that the Wells gabbro was intruded first as a mafic differentiate of the Oregon Dome/Snowy Mountain Dome magma, and was later intruded by the anorthositic gabbro. This later intrusion was concurrent with the emplacement of the Speculator Sheet and the Thirteenth Lake Dome. These data suggest that the contacts of anorthosites against country rock in the southern Adirondacks are igneous and not the product of sedimentation on an anorthositic basement. Textural and analytical evidence and graphical analysis suggest that the differing metamorphic mineral assemblages are controlled by variations in water fugacity. The development of orthopyroxene-plagio-clase coronas on some of the garnets is dependent on the iron contents of the garnets. / Master of Science

The designers of architecture in our national and state parks appear remarkably unenlightened in a day when the design of nearly all our structures is being given a careful re-analysis of function and purpose. Indeed, these designers go to great lengths to avoid admitting that any progress has been made in the building profession in the past 300 years. This thesis is an attempt to refute the current dominant philosophy of national park architecture, and to present a possible new approach to the problem. The building designs included here, for an actual site in the Adirondack mountains of New York, are intended to illustrate the tenet of contemporary structures for the needs of contemporary man. / Master of Science

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The role of collaboration within conservation is of increasing interest to scholars, managers and forest communities. Collaboration can take many forms, but one under-studied topic is the form and content of public discourses across conservation project timelines. To understand the discursive processes that influence conservation decision-making, this research evaluates the use of collaborative rhetoric and claims about place within discourses of conservation in the Adirondacks. Local newspaper articles and editorials published from January 1996 to December 2013 and concerning six major conservation projects were studied using content analysis. Results show that collaborative rhetoric increased during the study period, and conflict discourses declined, in concert with the rise of collaborative planning efforts. Data also show an increasing convergence between conservation sponsors and local communities regarding the economic benefits of conservation and the importance of public participation. The study has value in examining representations of place and media claims-making strategies within conservation discourses, an important topic as natural resource managers increasingly embrace community-based natural resource management.

This creative nonfiction dissertation is a book of essays that explore the author's life and relationship to Upstate New York. The project also connects this experience to gender and trauma. Though the topics range from local history to cosmetic surgical procedures, the essays are collected by how they illuminate cultural tensions and universal truths. These essays are preceded by a critical preface that examines the differences between essays collections, books of essays, and argues for the recognition of narrative nonfiction as an artistic choice.

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