Bedrock Geology of the Adirondack Region

Precambrian rocks of Adirondack Region were part of a global system of mountains whose formation approximately one billion years ago led to the assembly of a supercontinent called Rodinia. In New York State, the eroded remnants of these enormous mountains extend beneath the Paleozoic cover rocks on the edge of the Adirondack topographic dome to form the basement rocks of New York State and connect, through exposures in the Thousand Islands Region, to the bulk of the contiguous Grenville Province of the Canadian Shield. Similar rocks are exposed in basement windows along the spine of the much younger Appalachian Mountains and can be traced into Mexico and beyond. Like other areas in the Grenville Province, the High Peaks region of New York is underlain by a large intrusive body of massif anorthosite, a rock composed of exceptionally large crystals of plagioclase feldspar. Rocks in the Adirondacks range in age from approximately 1350 to 1000 million years old and record as many as three or four tectonic events which were part of the Grenville Orogenic Cycle. The net results of these events were high-grade metamorphism, strong deformation, and the widespread overprinting of original relationships and primary textural features. Younger Paleozoic rocks include Cambrian and Ordovician sandstones, limestones, and shales deposited on the eroded metamorphic and igneous basement. These sedimentary rocks are found in fault-bounded outliers within the Adirondack massif and around the Adirondack margins. The current topography of the Adirondacks is related to doming which began about 180 million years ago, when the Atlantic Ocean opened; although the reason(s) for this doming remain to be fully elucidated. Doming has stripped away the younger Paleozoic rocks and exposed the roots of the mountains, which at one time were deformed and metamorphosed deep in the crust

Vermont Agriculture and Food System Plan 2020 -- A Review of Recommendations (Part One)

Key Findings in reviewing the Vermont Agriculture and Food System Plan: 1. All recommendations in this review have been coded into eight thematic categories to be used more effectively by stakeholders. 2. We identify four clusters of recommendations to assist stakeholders in understanding the relationships between categories and enabling understanding of the various stakeholders and resources necessary to implement recommendations from different briefs 3. 87% of recommendations either request direct funding for an initiative or recommend a capital expenditure. With financial challenges amidst COVID-19, we highlight eight recommendations for a Vermont Food System that could move forward without financial resources. 4. In the future, giving authors a guide for writing recommendations would make them easier to categorize and implement

Age and Origin of Monazite Symplectite in an Iron Oxide-Apatite Deposit in the Adirondack Mountains, New York, USA: Implications for Tracking Fluid Conditions

Monazite crystals, intergrown with allanite, fluorapatite, and quartz from the Cheever Mine iron oxide-apatite (IOA-type) deposit in Essex County, New York, USA, display rare symplectite textures. Electron probe wavelength-dispersive spectrometry (WDS) mapping and major and trace element characterization of these features reveal a natural experiment in fluid-mediated monazite recrystallization. Two types of monazite with symplectite intergrowths have been recognized (Type I and II). Both types of symplectite development are associated with a decrease in HREE, Si, Ca, Th, and Y, but an increase in both La and Ce in monazite. Electron microprobe Th-U-total Pb analysis of Type I monazite with suitable ThO2 concentrations yielded a weighted mean age of 980 ± 5.8 Ma (MSWD: 3.3), which is interpreted as the age of monazite formation and the onset of symplectite development. Both types of monazite formed during a series of reactions from fluorapatite, and possibly britholite, to produce the final assemblage of monazite, allanite, and fluorapatite. Monazite formation was likely a response to evolving fluid conditions, which favored monazite stability over fluorapatite at ca. 980 Ma, possibly a NaCl brine. A subsequent transition to a Ca-dominated fluid may have then promoted the consumption of monazite to produce another generation of allanite and fluorapatite. Our results indicate that recrystallized monazite formed during fluid-mediated processes that, over time, trended towards an increasingly pure end-member composition. Regionally, these data are consistent with a magmatic-origin followed by fluid-mediated remobilization of select phases at subsolidus conditions for the Adirondack IOA deposits

Historical Patterns and Effects of Changes In Adirondack Climates Since the Early 20th Century

Analysis of weather data from seven United States Historical Climatology Network stations in the Adirondack region reveals statistically significant warming over the last 30 years during June and September, but no significant trends in the other months. The warmest intervals of the 1926-2005 period were the early 1930s, 1949-1954, and 1997-2003. These findings are consistent with similar analyses of northern New York weather data by Kathie Delio, but somewhat less so with earlier works by the first author and others. In this paper, we also discuss the effects of various interpretive methodologies on the study of regional climate and present new phonological data from the Adirondack region. We find little evidence of major biotic responses to weather trends in recent decades, perhaps because most such trends are still largely obscured by inter-annual variability, but a significant reduction in the duration of ice cover has occurred on local lakes. In addition, an increase of river discharge during the 20th century probably reflects a long-term increase in precipitation, particularly during fall