%0 Journal Article %J Minerals %D 2019 %T A Review of Boron-Bearing Minerals (Excluding Tourmaline) in the Adirondack Region of New York State %A Bailey, D. G. %A M. V. Lupulescu %A Darling, R. S. %A Singer, J. W. %A S. C. Chamberlain %K Adirondack Mountains %K boron minerals %K danburite %K datolite %K dumortierite %K grandidierite %K Grenville Province %K harkerite %K kornerupine %K prismatine %K serendibite %K sinhalite %K stillwellite-(Ce) %K vonsenite %K warwickite %X
Boron is a biologically important element, but its distribution in the natural environment and its behavior during many geological processes is not fully understood. In most metamorphic and igneous environments, boron is incorporated into minerals of the tourmaline supergroup. In high-grade metamorphic terranes like that of the Adirondack region of northern New York State, uncommon rock compositions combined with unusual and variable geologic conditions resulted in the formation of many additional boron-bearing minerals. This paper reviews the occurrences and geological settings of twelve relatively uncommon boron-bearing minerals in the southern Grenville Province of upstate New York and provides new chemical and Raman spectral data for seven of these minerals. The boron minerals range from relatively simple metal borates (e.g., vonsenite), to chemically complex borosilicates (e.g., prismatine), to a relatively rare borosilicate-carbonate (e.g., harkerite). Some are of primary igneous origin, while others are formed by a variety of prograde and retrograde metamorphic processes or by metasomatic/hydrothermal processes. Most of the boron minerals are formed within, or adjacent to, metasedimentary lithologies that surround the anorthositic massifs of the central Adirondacks. The metasedimentary rocks are thought to be the source of most of the boron, although additional boron isotope studies are needed to confirm this and to constrain the mechanisms of the formation of these unusual minerals.
%B Minerals %V 9 %P 644 %8 10/2019 %G eng %U https://www.mdpi.com/2075-163X/9/10/644 %N 10 %R 10.3390/min9100644 %0 Journal Article %J Minerals %D 2019 %T Age and Origin of Silicocarbonate Pegmatites of the Adirondack Region %A Chiarenzelli, Jeffrey %A M. V. Lupulescu %A Robinson, George %A Bailey, David %A Singer, Jared %K Adirondack Mountains %K calc–silicate minerals %K Carthage-Colton shear zone %K exhumation %K Grenville Province %K Ottawan Orogeny %K silicocarbonate %K skarns %K U–Pb zircon geochronology %K vein-dykes %XMonazite 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.
%B Minerals %V 9 %P 65 %8 Jan-21-2019 %G eng %U http://www.mdpi.com/2075-163X/9/1/65 %N 1 %! Minerals %R 10.3390/min9010065 %0 Journal Article %J Geosciences %D 2018 %T Age and Origin of the Mesoproterozoic Iron Oxide-Apatite Mineralization, Cheever Mine, Eastern Adirondacks, NY %A Chiarenzelli, Jeffrey %A M. V. Lupulescu %A Regan, Sean %A Singer, Jared %K Adirondack Mountains %K Cheever Mine %K Grenville Province %K iron oxide-apatite deposits (IOA deposits) %K Lyon Mountain Granite %K U-Pb zircon geochronology %XAt the Cheever Mine, located in the eastern Adirondack Mountains of the Mesoproterozoic Grenville Province, iron oxide-apatite ore forms a narrow (<3 m) sheet cross-cutting metasomatically altered, magnetite-bearing, albite-rich leucogranitic host rocks of the Lyon Mountain Granite suite. Zircon from the ore and five samples of country rock were dated by Laser Ablation-Multi-Collector-Inductively Coupled Plasma-Mass Spectrometry. The ore yielded a Concordia age of 1033.6 ± 2.9 Ma while three samples of host rock yielded ages of 1036.3 ± 2.9, 1040 ± 11, and 1043.9 ± 4.1 Ma. Two additional samples of host rock yielded older ages of 1059.6 ± 3.4 and 1066.0 ± 6.3 Ma and contain zircon xenocrystic cores with 207Pb/206Pb ages up to 1242 Ma. The zircons analyzed, including those separated from the ore, have characteristics typically associated with an igneous origin including size, shape, inclusions, oscillatory zoning, typical chondrite-normalized REE patterns, U contents, and U/Th ratios. This data establishes the age of the ore and alteration and a temporal, and likely genetic, connection between the ore and members of the Lyon Mountain Granite suite. A model invoking melting of Shawinigan country rocks, magmatic differentiation, and long-lived magmatic and metasomatic input along extensional fault conduits is proposed for the ore’s genesis. At the Cheever Mine, magmatic hydrothermal fluids and/or post-intrusion alteration appears not to have had a major impact on zircon, which preserves original U-Pb systematics.
%B Geosciences %V 8 %P 345 %8 09/2018 %G eng %U http://www.mdpi.com/2076-3263/8/9/345 %N 9 %! Geosciences %R 10.3390/geosciences8090345 %0 Journal Article %J The Wilson Journal of Ornithology %D 2017 %T Altitudinal Range Shifts of Birds at the Southern Periphery of the Boreal Forest: 40 Years of Change in the Adirondack Mountains %A J. J. Kirchman %A Van Keuren, A. E. %K Adirondack Mountains %K boreal forest %K climate change %K elevation gradient %K range dynamics %K resurvey %XStudies of geographic range shifts in response to climate warming that use data from Christmas Bird Counts or repeated state and provincial faunal atlases are better at detecting latitudinal shifts than altitudinal shifts because the coarse geographic scale of most citizen-science survey units masks the substantial elevational variation within their boundaries. To more directly measure altitudinal range shifts of forest-breeding bird species, we repeated an altitudinal transect survey conducted 40 years ago at Whiteface Mountain in the Adirondacks, New York, USA. We conducted roadside bird surveys at dawn and dusk at seven survey stations that ranged in altitude from 500 m to 1,425 m. We found considerable interspecific variation in the movement of altitudinal ranges, but document a preponderance of uphill shifts in both upper and lower boundaries of altitudinal breeding ranges. The shift of abundance-weighted mean altitudes for 42 species detected in both survey periods wasþ82.8 m. These shifts are correlated with a regional trend toward warmer summers from Adirondack weather station data collected over this same time period. Upper range boundaries have shifted more than lower boundaries, resulting in novel bird communities at some elevations (e.g., we found 13 species at 1,425 m vs 7 species at this altitude in 1974), resulting in a flattening of the altitudinal gradient of species richness. At low elevations we encountered several species that were not recorded on the transect in 1974, a trend we attribute to climate warming and anthropogenic habitat change at low altitudes. Our resurvey shows that there have been substantial upward range shifts in most bird species on Whiteface Mountain in the last four decades, and provides a basis for reassessment of altitudinal range dynamics at the southern edge of the North American boreal forest in the coming decades.
%B The Wilson Journal of Ornithology %V 129 %P 742–753 %G eng %U http://www.bioone.org/doi/full/10.1676/16-164.1 %N 4 %R 10.1676/16-164.1 %0 Journal Article %J Geosphere %D 2011 %T Using Pegmatite Geochronology to Constrain Temporal Events in the Adirondack Mountains %A M. V. Lupulescu %A J. R. Chiarenzelli %A Pullen, A. T. %A Price, J. D. %K Adirondack Mountains %K geochronology %K Pegmatite %XU-Pb laser ablation–multicollector–inductively coupled plasma–mass spectrometry (LA-MC-ICP-MS) ages have been determined from large zircon crystals separated from pegmatites of the Adirondack Mountains, New York. Emplacement and metamorphic ages ranging from 949 ± 10 to 1222 ± 12 Ma help constrain the timing of igneous, metamorphic, and deformational history of the region, and are associated with Shawinigan, Ottawan, and Rigolet orogenesis. Geologically reasonable ages were obtained from most zircon separates despite large size, a limited number of grains, high uranium and thorium contents, dark and opaque interiors, high density of fractures, and widespread areas of metamictization and Pb loss. However, few grains show zoning or differences in composition when viewed with the backscattered mode on the scanning electron microscope. Large, clear, internally featureless, U-poor grains yield the best constrained ages. U-Th-Pb monazite ages, determined by electron probe, vary from 874 ± 27 Ma to 297 ± 62; the younger age may reflect the timing of hydrothermal fluid infiltration related to late Acadian events. This study suggests that, with appropriate care, zircons from pegmatites are a reasonable target for LA-MC-ICP-MS geochronology, widening the current arsenal of sampling targets.
%B Geosphere %V 7 %P 23-29 %G eng %U http://dx.doi.org/10.1130/GES00596.1 %R 10.1130/GES00596.1 %0 Journal Article %J Rhodora %D 2010 %T A 23-Year Assessment of Vegetation Composition and Change in the Adirondack Alpine Zone, New York State %A Robinson, S. C. %A Ketchledge, E. H. %A Fitzgerald, B. T. %A Raynal, D. J. %A Kimmerer, R. W. %K Adirondack Mountains %K alpine flora %K bryophytes %K permanent transect %K succession %K vegetation change %XThe Adirondack Mountains of New York State hold some of the southernmost communities of alpine vegetation in the eastern United States. Containing the greatest concentration of rare and endangered species in New York State, this ∼12,000-year-old ecosystem is important to understanding the ecological history of northeastern North America. In order to monitor floristic and vegetational shifts over time, 11 permanent transects were established in 1984 on four summits (Wright, Algonquin, Boundary, and Iroquois) of the MacIntyre Range in the Adirondack High Peaks region. Using the point-intercept method, all 11 transects were sampled in 1984, 1994, 2002, and 2007. Vegetation composition changed significantly over the 23-year period, with an overall decrease in bryophytes/lichens and an increase in vascular plants, indicating that vascular plants were replacing bryophytes, particularly in areas not disturbed by hikers. Community similarity was high among all transects, and increased with time for vascular plants as they became more abundant, indicating a successional convergence. Compositional shifts may also reflect effects of global warming and atmospheric deposition on alpine plant communities.
%B Rhodora %V 112 %P 355-377 %G eng %U http://dx.doi.org/10.3119/09-03.1 %R 10.3119/09-03.1 %0 Journal Article %J American Journal of Botany %D 2004 %T Bryophyte Dispersal Inferred from Colonization of an Introduced Substratum on Whiteface Mountain, New York %A N. G. Miller %A McDaniel, S. F. %K Adirondack Mountains %K bryophyte %K calcicole %K calcium carbonate substrata %K Long-distance dispersal %K ruderal %XA long-standing debate in bryophyte biogeography concerns the frequency of long-distance spore dispersal. The diversity of bryophytes on mortared rock walls along the Veterans Memorial Highway on Whiteface Mountain, New York, USA, was studied to document the recruitment of species over the 65 years since the highway was constructed. The highway is situated in the Adirondack Mountains, a relatively unpopulated region with a largely acidic flora. The introduction of mortar has increased the bryophyte diversity by 50% above that of native lithic substrata on the mountain. The composition of the native and mortar floras differed greatly, suggesting that the walls were not colonized by locally abundant ruderal species. Many of the species sampled on the walls are typically found only in lower elevation forested sites, distant (∼5 km or more) from the highway, and not on anthropogenic calcium carbonate. These results suggest that a bryophyte community consisting of common and uncommon species assembled from distant sites at the rate of at least one species per year in the last 65 years. These data provide the ecological context for experimental and phylogeographic studies and suggest that some bryophytes may be capable of routine dispersal over distances of at least 5 km.
%B American Journal of Botany %V 91 %P 1173-1182 %G eng %U http://dx.doi.org/10.3732/ajb.91.8.1173 %R 10.3732/ajb.91.8.1173 %0 Journal Article %J The Bryologist %D 2000 %T Winter Dispersal of Bryophyte Fragments in the Adirondack Mountains, New York %A McDaniel, S. F. %A N. G. Miller %K Adirondack Mountains %K bryophytes %K Dispersal %K New York %K winter %XBryophyte and vascular plant fragments were obtained from late-spring snowbeds at three localities in the Adirondack Mountains, New York. Fragment diversity in samples at alpine and krummholz sites far exceeded that at a forested site, and the diversity of bryophyte species represented by the fragments surpassed that of vascular plants. Approximately 82% of all bryophyte fragments found were in sufficiently good condition to permit identification to species or genus. Statistically significant differences in fragment species diversity occurred between the alpine sites and the forested site, but not between the two alpine sites. The consistent presence of liverworts in the alpine samples indicates that their absence from late-glacial sediments may be due more to taphonomy than either an absence of hepatics from the late-glacial flora or an inability of hepatics to disperse by gametophyte fragments. We detected only a few allochthonous fragments in our samples, and these were of bryophyte species characteristic of lower elevation balsam fir and red spruce-balsam fir forests. In alpine tundra, winter-dispersed fragments of bryophytes may serve as vegetative diaspores, providing a mechanism for rapid establishment of new populations every year following snow melt.
%B The Bryologist %V 103 %P 592-600 %G eng %U http://dx.doi.org/10.1639/0007-2745(2000)103[0592:WDOBFI]2.0.CO;2 %R 10.1639/0007-2745(2000)103[0592:WDOBFI]2.0.CO;2