The Snake River Plain Volcanic Province: Insights from Project Hotspot

NASA Astrophysics Data System (ADS)

Shervais, J. W.; Potter, K. E.; Hanan, B. B.; Jean, M. M.; Duncan, R. A.; Champion, D. E.; Vetter, S.; Glen, J. M. G.; Christiansen, E. H.; Miggins, D. P.; Nielson, D. L.

2017-12-01

The Snake River Plain (SRP) Volcanic Province is the best modern example of a time-transgressive hotspot track beneath continental crust. The SRP began 17 Ma with massive eruptions of Columbia River basalt and rhyolite. After 12 Ma volcanism progressed towards Yellowstone, with early rhyolite overlain by basalts that may exceed 2 km thick. The early rhyolites are anorogenic with dry phenocryst assemblages and eruption temperatures up to 950C. Tholeiitic basalts have major and trace element compositions similar to ocean island basalts (OIB). Project Hotspot cored three deep holes in the central and western Snake River Plain: Kimama (mostly basalt), Kimberly (mostly rhyolite), and Mountain Home (lake sediments and basaslt). The Kimberly core documents rhyolite ash flows up to 700 m thick, possibly filling a caldera or sag. Chemical stratigraphy in Kimama and other basalt cores document fractional crystallization in relatively shallow magma chambers with episodic magma recharge. Age-depth relations in the Kimama core suggest accumulation rates of roughly 305 m/Ma. Surface and subsurface basalt flows show systematic variations in Sr-Nd-Pb isotopes with distance from Yellowstone interpreted to reflect changes in the proportion of plume source and the underlying heterogeneous cratonic lithosphere, which varies in age, composition, and thickness from west to east. Sr-Nd-Pb isotopes suggest <5% lithospheric input into a system dominated by OIB-like plume-derived basalts. A major flare-up of basaltic volcanism occurred 75-780 ka throughout the entire SRP, from Yellowstone in the east to Boise in the west. The youngest western SRP basalts are transitional alkali basalts that range in age from circa 900 ka to 2 ka, with trace element and isotopic compositions similar to the plume component of Hawaiian basalts. These observations suggest that ancient SCLM was replaced by plume mantle after the North America passed over the hotspot in the western SRP, which triggered renewed

Prodigious degassing of a billion years of accumulated radiogenic helium at Yellowstone

USGS Publications Warehouse

Lowenstern, Jacob B.; Evans, William C.; Bergfeld, D.; Hunt, Andrew G.

2014-01-01

Helium is used as a critical tracer throughout the Earth sciences, where its relatively simple isotopic systematics is used to trace degassing from the mantle, to date groundwater and to time the rise of continents1. The hydrothermal system at Yellowstone National Park is famous for its high helium-3/helium-4 isotope ratio, commonly cited as evidence for a deep mantle source for the Yellowstone hotspot2. However, much of the helium emitted from this region is actually radiogenic helium-4 produced within the crust by α-decay of uranium and thorium. Here we show, by combining gas emission rates with chemistry and isotopic analyses, that crustal helium-4 emission rates from Yellowstone exceed (by orders of magnitude) any conceivable rate of generation within the crust. It seems that helium has accumulated for (at least) many hundreds of millions of years in Archaean (more than 2.5 billion years old) cratonic rocks beneath Yellowstone, only to be liberated over the past two million years by intense crustal metamorphism induced by the Yellowstone hotspot. Our results demonstrate the extremes in variability of crustal helium efflux on geologic timescales and imply crustal-scale open-system behaviour of helium in tectonically and magmatically active regions.

Geologic history of Siletzia, a large igneous province in the Oregon and Washington Coast Range: correlation to the geomagnetic polarity time scale and implications for a long-lived Yellowstone hotspot

USGS Publications Warehouse

Wells, Ray; Bukry, David; Friedman, Richard; Pyle, Douglas; Duncan, Robert; Haeussler, Peter J.; Wooden, Joe

2014-01-01

Siletzia is a basaltic Paleocene and Eocene large igneous province in coastal Oregon, Washington, and southern Vancouver Island that was accreted to North America in the early Eocene. New U-Pb magmatic, detrital zircon, and 40Ar/39Ar ages constrained by detailed field mapping, global nannoplankton zones, and magnetic polarities allow correlation of the volcanics with the 2012 geologic time scale. The data show that Siletzia was rapidly erupted 56–49 Ma, during the Chron 25–22 plate reorganization in the northeast Pacific basin. Accretion was completed between 51 and 49 Ma in Oregon, based on CP11 (CP—Coccolith Paleogene zone) coccoliths in strata overlying onlapping continental sediments. Magmatism continued in the northern Oregon Coast Range until ca. 46 Ma with the emplacement of a regional sill complex during or shortly after accretion. Isotopic signatures similar to early Columbia River basalts, the great crustal thickness of Siletzia in Oregon, rapid eruption, and timing of accretion are consistent with offshore formation as an oceanic plateau. Approximately 8 m.y. after accretion, margin parallel extension of the forearc, emplacement of regional dike swarms, and renewed magmatism of the Tillamook episode peaked at 41.6 Ma (CP zone 14a; Chron 19r). We examine the origin of Siletzia and consider the possible role of a long-lived Yellowstone hotspot using the reconstruction in GPlates, an open source plate model. In most hotspot reference frames, the Yellowstone hotspot (YHS) is on or near an inferred northeast-striking Kula-Farallon and/or Resurrection-Farallon ridge between 60 and 50 Ma. In this configuration, the YHS could have provided a 56–49 Ma source on the Farallon plate for Siletzia, which accreted to North America by 50 Ma. A sister plateau, the Eocene basalt basement of the Yakutat terrane, now in Alaska, formed contemporaneously on the adjacent Kula (or Resurrection) plate and accreted to coastal British Columbia at about the same time

River Incision and Knickpoints on the Flank of the Yellowstone Hotspot — Alpine Canyon of the Snake River, Wyoming

NASA Astrophysics Data System (ADS)

Tuzlak, D.; Pederson, J. L.

2015-12-01

Understanding patterns of deformation and testing geophysical models in the dynamic region of the Yellowstone Hotspot requires Quaternary-scale records of incision and uplift, which are currently absent. This study examines fluvial terraces and longitudinal-profile metrics along Alpine Canyon of the Snake River, WY. Because the Snake is the only regional river crossing from the uplifting Yellowstone Plateau and flowing into the subsiding Eastern Snake River Plain, it provides an opportunity to investigate both ends of the phenomenon. Field observations through Alpine Canyon indicate that Pleistocene incision rates in this region are relatively high for the interior western U.S., that the river switches between bedrock and alluvial forms, and that incision/uplift is not uniform. Two endmembers of regional deformation may be tested: 1) the arch of high topography surrounding Yellowstone is uplifting and terraces converge downstream as incision rates decrease towards the Snake River Plain, or 2) baselevel fall originates at the subsiding Snake River Plain and terraces diverge as incision rates increase downstream. Datasets include surficial mapping, rock strength measurements, surveying of the longitudinal profile and terraces using RTK-GPS, optically stimulated luminescence dating of fluvial-terrace deposits, and investigation of drainages through ksn and χ analyses. Initial results indicate that there are four primary terrace deposits along the canyon, three of which are timed with glacial epochs. Considering the relative heights of terrace straths and preliminary ages, incision rates are indeed relatively high. There is a major knickzone covering the last 15 km of the canyon that is also reflected in tributary profiles and is consistent with a wave of incision propagating upstream, favoring the second endmember of active baselevel fall downstream.

Genesis of Middle Miocene Yellowstone hotspot-related bonanza epithermal Au-Ag deposits, Northern Great Basin, USA

NASA Astrophysics Data System (ADS)

Saunders, J. A.; Unger, D. L.; Kamenov, G. D.; Fayek, M.; Hames, W. E.; Utterback, W. C.

2008-09-01

Epithermal deposits with bonanza Au-Ag veins in the northern Great Basin (NGB) are spatially and temporally associated with Middle Miocene bimodal volcanism that was related to a mantle plume that has now migrated to the Yellowstone National Park area. The Au-Ag deposits formed between 16.5 and 14 Ma, but exhibit different mineralogical compositions, the latter due to the nature of the country rocks hosting the deposits. Where host rocks were primarily of meta-sedimentary or granitic origin, adularia-rich gold mineralization formed. Where glassy rhyolitic country rocks host veins, colloidal silica textures and precious metal-colloid aggregation textures resulted. Where basalts are the country rocks, clay-rich mineralization (with silica minerals, adularia, and carbonate) developed. Oxygen isotope data from quartz (originally amorphous silica and gels) from super-high-grade banded ores from the Sleeper deposit show that ore-forming solutions had δ 18O values up to 10‰ heavier than mid-Miocene meteoric water. The geochemical signature of the ores (including their Se-rich nature) is interpreted here to reflect a mantle source for the “epithermal suite” elements (Au, Ag, Se, Te, As, Sb, Hg) and that signature is preserved to shallow crustal levels because of the similar volatility and aqueous geochemical behavior of the “epithermal suite” elements. A mantle source for the gold in the deposits is further supported by the Pb isotopic signature of the gold ores. Apparently the host rocks control the mineralization style and gangue mineralogy of ores. However, all deposits are considered to have derived precious metals and metalloids from mafic magmas related to the initial emergence of the Yellowstone hotspot. Basalt-derived volatiles and metal(loid)s are inferred to have been absorbed by meteoric-water-dominated geothermal systems heated by shallow rhyolitic magma chambers. Episodic discharge of volatiles and metal(loid)s from deep basaltic magmas mixed with

Mantle-lithosphere interaction beneath the Yellowstone-Snake River province

NASA Astrophysics Data System (ADS)

van Keken, P. E.; Lin, S.

2006-12-01

The Yellowstone-Snake River province (YSRP) is one the few currently active continental hotspot locations and the only one with a clear age progression from 16-17 Ma eruptions at the Oregon-Nevada border to the present day activity at in Western Wyoming. The province has a number of characteristics that are quite similar to oceanic hotspot regions, which include a topographic bulge and geoid anomaly. The initial silicic magmatism is contemporaneous with the Columbia River Basalts, but this would require significant northward transport of basalt from the hotspot track, which is potentially accommodated by lateral transport in the crust or by a sideways transport from more competent lithosphere to a weaker spot. We will present 3D models of plumes and plume heads interacting with the lithosphere for the YSRP following the approach of Lin et al. (2005). We are particularly interested in the role of the variable properties of the lithosphere and surface tectonics influence the magmatic emplacement. We investigate the type conditions under which we can generate the Columbia River Basalts as a part of a single Yellowstone plume rising below the western US. This provides important estimates of the original size of the plume head, the current buoyancy flux and the lateral transport of mantle below the lithosphere. S.C. Lin, B.Y. Kuo, L.Y. Chiao, P.E. van Keken, Thermal plume models and melt generation in East Africa: A dynamical modeling approach, Earth Planet. Sci. Lett., 237, 175-192, 2005.

The McDermitt Caldera, NV-OR, USA: Geologic mapping, volcanology, mineralization, and high precision 40Ar/39Ar dating of early Yellowstone hotspot magmatism

NASA Astrophysics Data System (ADS)

Henry, C. D.; Castor, S. B.; Starkel, W. A.; Ellis, B. S.; Wolff, J. A.; Heizler, M. T.; McIntosh, W. C.

2012-12-01

�0.02 Ma) in the west floor of the caldera are the oldest middle Miocene silicic rocks near the caldera. Other pre-caldera rocks are a mix of variably peralkaline, distal ignimbrites; biotite rhyolite domes and lavas; and variably peralkaline rhyolite lavas that were emplaced between about 16.50 and 16.36 Ma. Silicic volcanism around the McDermitt caldera is some of the oldest of the Yellowstone hotspot track, but two known calderas in NW Nevada and unidentified sources of distal ignimbrites near McDermitt are older than the McDermitt caldera. Initial hotspot silicic volcanism occurred over a large area across NW Nevada, SE Oregon, and SW Idaho.

Lessons from geothermal gases at Yellowstone

NASA Astrophysics Data System (ADS)

Lowenstern, J. B.; Bergfeld, D.; Evans, W.; Hurwitz, S.

2015-12-01

The magma-hydrothermal system of the Yellowstone Plateau Volcanic Field encompasses over ten thousand individual springs, seeps, and fumaroles spread out over >9000 square kilometers, and produces a range of acid, neutral and alkaline waters. A prominent model (Fournier, 1989 and related papers) concludes that many neutral and alkaline fluids found in hot springs and geysers are derived from a uniform, high-enthalpy parent fluid through processes such as deep boiling and mixing with dilute meteoric groundwater. Acid waters are generally condensates of gas-bearing steam that boils off of subsurface geothermal waters. Our recent studies of gases at Yellowstone (Lowenstern et al., 2015 and references therein) are compatible with such a model, but also reveal that gases are largely decoupled from thermal waters due to open-system addition of abundant deep gas to (comparatively) shallow circulating thermal waters. Fumarole emissions at Yellowstone range from gas-rich (up to 15 mol%) composed of deeply derived CO2, He and CH4, to steam-rich emissions (<0.01% gas) dominated by N2 and Ar. The clear implication is that deep gas is diluted with atmospheric gas boiled off of geothermal liquids. The general trend is antithetical to that predicted by progressive boiling of a parent fluid (Rayleigh or batch degassing), where decreasing gas content should correlate with increasing proportions of soluble gas (i.e., CO2). Deep gas at Yellowstone fits into two general categories: 1) mantle-derived CO2 with a hotspot He isotope signature (>16 RA) and low CH4 and He concentrations and 2) mantle-derived CO2 with much higher CH4 and/or He concentrations and abundant radiogenic He picked up from crustal degassing. Individual thermal areas have distinct CH4/He. It remains unclear whether some gas ratios mainly reflect subsurface geothermal temperatures. Instead, they may simply reflect signatures imparted by local rock types and mixing on timescales too fast for reequilibration. Overall

Feeding ecology of native and nonnative salmonids during the expansion of a nonnative apex predator in Yellowstone Lake, Yellowstone National Park

USGS Publications Warehouse

Syslo, John M.; Guy, Christopher S.; Koel, Todd M.

2016-01-01

The illegal introduction of Lake Trout Salvelinus namaycush into Yellowstone Lake, Yellowstone National Park, preceded the collapse of the native population of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri, producing a four-level trophic cascade. The Yellowstone Cutthroat Trout population’s collapse and the coinciding increase in Lake Trout abundance provided a rare opportunity to evaluate the feeding ecology of a native prey species and a nonnative piscivore species after the restructuring of a large lentic ecosystem. We assessed diets, stable isotope signatures, and depth-related CPUE patterns for Yellowstone Cutthroat Trout and Lake Trout during 2011–2013 to evaluate trophic overlap. To evaluate diet shifts related to density, we also compared 2011–2013 diets to those from studies conducted during previous periods with contrasting Yellowstone Cutthroat Trout and Lake Trout CPUEs. We illustrate the complex interactions between predator and prey in a simple assemblage and demonstrate how a nonnative apex predator can alter competitive interactions. The diets of Yellowstone Cutthroat Trout were dominated by zooplankton during a period when the Yellowstone Cutthroat Trout CPUE was high and were dominated by amphipods when the CPUE was reduced. Lake Trout shifted from a diet that was dominated by Yellowstone Cutthroat Trout during the early stages of the invasion to a diet that was dominated by amphipods after Lake Trout abundance had increased and after Yellowstone Cutthroat Trout prey had declined. The shifts in Yellowstone Cutthroat Trout and Lake Trout diets resulted in increased trophic similarity of these species through time due to their shared reliance on benthic amphipods. Yellowstone Cutthroat Trout not only face the threat posed by Lake Trout predation but also face the potential threat of competition with Lake Trout if amphipods are limiting. Our results demonstrate the importance of studying the long-term feeding ecology of fishes in

Atlas of Yellowstone

USGS Publications Warehouse

Pierce, Kenneth L.; Marcus, A. W.; Meachan, J. E.; Rodman, A. W.; Steingisser, A. Y.; Allan, Stuart; West, Ross

2012-01-01

Established in 1872, Yellowstone National Park was the world’s first national park. In a fitting tribute to this diverse and beautiful region, the Atlas of Yellowstone is a compelling visual guide to this unique national park and its surrounding area. Ranging from art to wolves, from American Indians to the Yellowstone Volcano, and from geysers to population, each page explains something new about the dynamic forces shaping Yellowstone. Equal parts reference and travel guide, the Atlas of Yellowstone is an unsurpassed resource.

Yellowstone Lake/National Park

NASA Image and Video Library

1994-09-30

STS068-247-061 (30 September-11 October 1994) --- Photographed through the Space Shuttle Endeavour's flight windows, this 70mm frame centers on Yellowstone Lake in the Yellowstone National Park. North will be at the top if picture is oriented with series of sun glinted creeks and river branches at top center. The lake, at 2,320 meters (7,732 feet) above sea level, is the largest high altitude lake in North America. East of the park part of the Absaroka Range can be traced by following its north to south line of snow capped peaks. Jackson Lake is southeast of Yellowstone Park, and the connected Snake River can be seen in the lower left corner. Yellowstone, established in 1872 is the world's oldest national park. It covers an area of 9,000 kilometers (3,500 square miles), lying mainly on a broad plateau of the Rocky Mountains on the Continental Divide. It's average altitude is 2,440 meters (8,000 feet) above sea level. The plateau is surrounded by mountains exceeding 3,600 meters (12,000 feet) in height. Most of the plateau was formed from once-molten lava flows, the last of which is said to have occurred 100,000 years ago. Early volcanic activity is still evident in the region by nearly 10,000 hot springs, 200 geysers and numerous vents found throughout the park.

Early warning of active fire hotspots through NASA FIRMS fire information system

NASA Astrophysics Data System (ADS)

Ilavajhala, S.; Davies, D.; Schmaltz, J. E.; Murphy, K. J.

2014-12-01

Forest fires and wildfires can threaten ecosystems, wildlife, property, and often, large swaths of populations. Early warning of active fire hotspots plays a crucial role in planning, managing, and mitigating the damaging effects of wildfires. The NASA Fire Information for Resource Management System (FIRMS) has been providing active fire location information to users in easy-to-use formats for the better part of last decade, with a view to improving the alerting mechanisms and response times to fight forest and wildfires. FIRMS utilizes fires flagged as hotspots by the MODIS instrument flying aboard the Aqua and Terra satellites and sends early warning of detected hotspots via email in near real-time or as daily and weekly summaries. The email alerts can also be customized to send alerts for a particular region of interest, a country, or a specific protected area or park. In addition, a web mapping component, named "Web Fire Mapper" helps query and visualize hotspots. A newer version of Web Fire Mapper is being developed to enhance the existing visualization and alerting capabilities. Plans include supporting near real-time imagery from Aqua and Terra satellites to provide a more helpful context while viewing fires. Plans are also underway to upgrade the email alerts system to provide mobile-formatted messages and short text messages (SMS). The newer version of FIRMS will also allow users to obtain geo-located image snapshots, which can be imported into local GIS software by stakeholders to help further analyses. This talk will discuss the FIRMS system, its enhancements and its role in helping map, alert, and monitor fire hotspots by providing quick data visualization, querying, and download capabilities.

Life history migrations of adult Yellowstone Cutthroat Trout in the upper Yellowstone River

USGS Publications Warehouse

Ertel, Brian D.; McMahon, Thomas E.; Koel, Todd M.; Gresswell, Robert E.; Burckhardt, Jason

2017-01-01

Knowledge of salmonid life history types at the watershed scale is increasingly recognized as a cornerstone for effective management. In this study, we used radiotelemetry to characterize the life history movements of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in the upper Yellowstone River, an extensive tributary that composes nearly half of the drainage area of Yellowstone Lake. In Yellowstone Lake, Yellowstone Cutthroat Trout have precipitously declined over the past 2 decades primarily due to predation from introduced Lake Trout Salvelinus namaycush. Radio tags were implanted in 152 Yellowstone Cutthroat Trout, and their movements monitored over 3 years. Ninety-six percent of tagged trout exhibited a lacustrine–adfluvial life history, migrating upstream a mean distance of 42.6 km to spawn, spending an average of 24 d in the Yellowstone River before returning to Yellowstone Lake. Once in the lake, complex postspawning movements were observed. Only 4% of radio-tagged trout exhibited a fluvial or fluvial–adfluvial life history. Low prevalence of fluvial and fluvial–adfluvial life histories was unexpected given the large size of the upper river drainage. Study results improve understanding of life history diversity in potamodromous salmonids inhabiting relatively undisturbed watersheds and provide a baseline for monitoring Yellowstone Cutthroat Trout response to management actions in Yellowstone Lake.

Voluminous low δ18O magmas in the late Miocene Heise volcanic field, Idaho: Implications for the fate of Yellowstone hotspot calderas

USGS Publications Warehouse

Bindeman, I.N.; Watts, K.E.; Schmitt, A.K.; Morgan, L.A.; Shanks, P.W.C.

2007-01-01

We report oxygen isotope compositions of phenocrysts and U-Pb ages of zircons in four large caldera-forming ignimbrites and post-caldera lavas of the Heise volcanic field, a nested caldera complex in the Snake River Plain, that preceded volcanism in Yellowstone. Early eruption of three normal δ18O voluminous ignimbrites with δ18Oquartz = 6.4‰ and δ18Ozircon = 4.8‰ started at Heise at 6.6 Ma, and was followed by a 2‰–3‰ δ18O depletion in the subsequent 4.45 Ma Kilgore caldera cycle that includes the 1800 km3 Kilgore ignimbrite, and post-Kilgore intracaldera lavas with δ18Oquartz = 4.3‰ and δ18Ozircon = 1.5‰. The Kilgore ignimbrite represents the largest known low-δ18O magma in the Snake River Plain and worldwide. The post-Kilgore low δ18O volcanism likely represents the waning stages of silicic magmatism at Heise, prior to the reinitiation of normal δ18O silicic volcanism 100 km to the northeast at Yellowstone. The occurrence of low δ18O magmas at Heise and Yellowstone hallmarks a mature stage of individual volcanic cycles in each caldera complex. Sudden shifts in δ18O of silicic magmas erupted from the same nested caldera complexes argue against any inheritance of the low δ18O signature from mantle or crustal sources. Instead, δ18O age trends indicate progressive remelting of low δ18O hydrothermally altered intracaldera rocks of previous eruptions. This trend may be generally applicable to older caldera complexes in the Snake River Plain that are poorly exposed.

Values associated with management of Yellowstone cutthroat trout in Yellowstone National Park

USGS Publications Warehouse

Gresswell, Robert E.; Liss, W.J.

1995-01-01

Recent emphasis on a holistic view of natural systems and their management is associated with a growing appreciation of the role of human values in these systems. In the past, resource management has been perceived as a dichotomy between extraction (harvest) and nonconsumptive use, but this appears to be an oversimplified view of natural-cultural systems. The recreational fishery for Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) in Yellowstone National Park is an example of the effects of management on a natural-cultural system. Although angler harvest has been drastically reduced or prohibited, the recreational value of Yellowstone cutthroat trout estimated by angling factors (such as landing rate or size) ranks above that of all other sport species in Yellowstone National Park. To maintain an indigenous fishery resource of this quality with hatchery propagation is not economically or technically feasible. Nonconsumptive uses of the Yellowstone cutthroat trout including fish-watching and intangible values, such as existence demand, provide additional support for protection of wild Yellowstone cutthroat trout populations. A management strategy that reduces resource extraction has provided a means to sustain a quality recreational fishery while enhancing values associated with the protection of natural systems.

Optimal wildlife management in the greater Yellowstone ecosystem: A spatiotemporal model of disease risk

USDA-ARS?s Scientific Manuscript database

South of Yellowstone National Park there are twenty-three sites where elk herds are provided supplementary feeding during the winter and spring months. Supplementary feeding of elk in the Greater Yellowstone Ecosystem (GYE) has been practiced since the early twentieth century, but the practice has b...

Myxobolus cerebralis in native cutthroat trout of the Yellowstone Lake ecosystem

USGS Publications Warehouse

Koel, T.M.; Mahony, D.L.; Kinnan, K.L.; Rasmussen, C.; Hudson, C.J.; Murcia, S.; Kerans, B.L.

2006-01-01

The exotic parasite Myxobolus cerebralis was first detected in native adult Yellowstone cutthroat trout Oncorhynchus clarkii bouvierii from Yellowstone Lake in 1998, seriously threatening the ecological integrity of this pristine, naturally functioning ecosystem. We immediately began to assess the prevalence and spatial extent of M. cerebralis infection in Yellowstone cutthroat trout within Yellowstone Lake and to determine the infection risk of age-0 Yellowstone cutthroat trout, the relative abundance and actinospore production of lubificid worms, and the basic environmental characteristics of tributaries. During 1999-2001, juvenile and adult Yellowstone cutthroat trout were infected throughout Yellowstone Lake; the highest prevalence (15.3-16.4%) occurred in the northern and central regions. Exposure studies in 13 streams indicated that Pelican and Clear creeks and the Yellowstone River were positive for M. cerebralis; the highest prevalence (100%) and severity was found in Pelican Creek during mid-July. Sexually mature individuals of the oligochaete Tubifex tubifex were most abundant in early summer, were genetically homogenous, and were members of a lineage known to produce moderate to high levels of M. cerebralis triactinomyxons. Only 20 of the 3,037 sampled tubificids produced actinospores after 7 d in culture, and none of the actinospores were M. cerebralis. However, one non-actinospore-producing T. tubifex from Pelican Creek tested positive for M. cerebralis by polymerase chain reaction. Stream temperatures at Pelican Creek, a fourth-order, low-gradient stream, were over 20??C during the first exposure period, suggesting that T. tubifex were capable of producing triactinomyxons at elevated temperatures in the wild. Although the infection of otherwise healthy adult Yellowstone cutthroat trout within Yellowstone Lake suggests some resistance, our sentinel cage exposures indicated that this subspecies may be more susceptible to whirling disease than previous

Crustal Deformation in the Eastern Snake River Plain and Yellowstone Plateau Observed by SAR Interferometry

NASA Astrophysics Data System (ADS)

Aly, M. H.; Hughes, S. S.; Rodgers, D. W.; Glenn, N. F.; Thackray, G. D.

2007-12-01

The Snake River Plain-Yellowstone tectono-volcanic province was created when North America migrated over a fixed hotspot in the mantle. Synthetic Aperture Radar Interferometry (InSAR) has been applied in this study to address the recent tectono-volcanic activity in the Eastern Snake River Plain (ESRP) and the southwestern part of Yellowstone Plateau. InSAR results show that crustal deformation across the tectono-volcanic province is episodic. An episode of uplift (about 1 cm/yr) along the ESRP axial volcanic zone, directly southwest of Island Park, has been detected from a time-series of independent differential interferograms created for the 1993-2000 period. Episodes of subsidence (1 cm/yr) during 1997-2000 and uplift (3 cm/yr) during 2004-2006 have been also detected in the active Yellowstone caldera, just northeast of Island Park. The detected interferometric signals indicate that deformation across the axial volcanic zone near Island Park is inversely linked to deformation in the active Yellowstone caldera. One explanation is that the inverse motions reflect a flexure response of the ESRP crust to magma chamber activity beneath the active caldera, although other interpretations are possible. The time-series of differential interferograms shows that no regional deformation has occurred across the central part of ESRP during the periods of observations, but local surface displacements of 1-3 cm magnitude have been detected in the adjacent Basin-Range province. Differential surface movements of varying rates have been also detected along Centennial, Madison, and Hebgen faults between 1993 and 2006.

Chapter 5. Yellowstone cutthroat trout

Treesearch

Robert E. Gresswell

1995-01-01

The Yellowstone cutthroat trout is more abundant and inhabits a greater geographical range than does any other nonanadronnous subspecies of cutthroat trout (Varley and Gresswell 1988). The Yellowstone cutthroat trout was indigenous to the Snake River upstream from Shoshone Falls, Idaho, and the Yellowstone River above the Tongue River, Montana (Behnke 1992). Although...

P-wave tomography of the western United States: Insight into the Yellowstone hotspot and the Juan de Fuca slab

NASA Astrophysics Data System (ADS)

Tian, You; Zhao, Dapeng

2012-06-01

We used 190,947 high-quality P-wave arrival times from 8421 local earthquakes and 1,098,022 precise travel-time residuals from 6470 teleseismic events recorded by the EarthScope/USArray transportable array to determine a detailed three-dimensional P-wave velocity model of the crust and mantle down to 1000 km depth under the western United States (US). Our tomography revealed strong heterogeneities in the crust and upper mantle under the western US. Prominent high-velocity anomalies are imaged beneath Idaho Batholith, central Colorado Plateau, Cascadian subduction zone, stable North American Craton, Transverse Ranges, and Southern Sierra Nevada. Prominent low-velocity anomalies are imaged at depths of 0-200 km beneath Snake River Plain, which may represent a small-scale convection beneath the western US. The low-velocity structure deviates variably from a narrow vertical plume conduit extending down to ˜1000 km depth, suggesting that the Yellowstone hotspot may have a lower-mantle origin. The Juan de Fuca slab is imaged as a dipping high-velocity anomaly under the western US. The slab geometry and its subducted depth vary in the north-south direction. In the southern parts the slab may have subducted down to >600 km depth. A "slab hole" is revealed beneath Oregon, which shows up as a low-velocity anomaly at depths of ˜100 to 300 km. The formation of the slab hole may be related to the Newberry magmatism. The removal of flat subducted Farallon slab may have triggered the vigorous magmatism in the Basin and Range and southern part of Rocky Mountains and also resulted in the uplift of the Colorado Plateau and Rocky Mountains.

Three Short Videos by the Yellowstone Volcano Observatory

USGS Publications Warehouse

Wessells, Stephen; Lowenstern, Jake; Venezky, Dina

2009-01-01

This is a collection of videos of unscripted interviews with Jake Lowenstern, who is the Scientist in Charge of the Yellowstone Volcano Observatory (YVO). YVO was created as a partnership among the U.S. Geological Survey (USGS), Yellowstone National Park, and University of Utah to strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety. These video presentations give insights about many topics of interest about this area. Title: Yes! Yellowstone is a Volcano An unscripted interview, January 2009, 7:00 Minutes Description: USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers the following questions to explain volcanic features at Yellowstone: 'How do we know Yellowstone is a volcano?', 'What is a Supervolcano?', 'What is a Caldera?','Why are there geysers at Yellowstone?', and 'What are the other geologic hazards in Yellowstone?' Title: Yellowstone Volcano Observatory An unscripted interview, January 2009, 7:15 Minutes Description: USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers the following questions about the Yellowstone Volcano Observatory: 'What is YVO?', 'How do you monitor volcanic activity at Yellowstone?', 'How are satellites used to study deformation?', 'Do you monitor geysers or any other aspect of the Park?', 'Are earthquakes and ground deformation common at Yellowstone?', 'Why is YVO a relatively small group?', and 'Where can I get more information?' Title: Yellowstone Eruptions An unscripted interview, January 2009, 6.45 Minutes Description: USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers the following questions to explain volcanic

Infectious diseases of wolves in Yellowstone

USGS Publications Warehouse

Almberg, Emily S.; Cross, Paul C.; Hudson, Peter J.; Dobson, Andrew P.; Smith, Douglas W.; Stahler, Daniel R.

2016-01-01

The summer of 2005 began with such promise for wolves in Yellowstone.  The population had been at an all-time high the last few years, and the wolves appeared to be in good condition.  Several packs had been particularly busy during the breeding season, and early summer pup counts suggested another healthy crop of new wolves rising through the ranks.

Oxygen isotope evolution of the Lake Owyhee volcanic field, Oregon, and implications for low-δ18O magmas of the Snake River Plain - Yellowstone hotspot

NASA Astrophysics Data System (ADS)

Blum, T.; Kitajima, K.; Nakashima, D.; Valley, J. W.

2013-12-01

The Snake River Plain - Yellowstone (SRP-Y) hotspot trend is one of the largest known low-δ18O magmatic provinces, yet the timing and distribution of hydrothermal alteration relative to hotspot magmatism remains incompletely understood. Existing models for SRP-Y low-δ18O magma genesis differ regarding the timing of protolith alteration (e.g. Eocene vs. present), depth at which alteration occurs (e.g. 15 km vs. <5 km), and physical controls on the extent of alteration (e.g. caldera collapse, crustal scale fluid flow, etc.). We expand the existing oxygen isotope data set for zircon in the Lake Owyhee volcanic field (LOVF) of east central Oregon to further identify magmatic oxygen isotope trends within the field. These data offer insight into the timing of alteration and the extent of the greater SRP-Y low-δ18O province, as well as the conditions that generate large low-δ18O provinces. 16-14 Ma silicic volcanism in the LOVF is linked to the pre-14 Ma SRP-Y hotspot, with volcanism partially overlapping extension in the north-south trending Oregon-Idaho Graben (OIG). Ion microprobe analyses of zircons from 16 LOVF silicic lavas and tuffs reveal homogeneous zircons on both the single grain and hand sample scales: individual samples have 2 S.D. for δ18O ranging from 0.27 to 0.96‰ (SMOW), and sample averages ranging from 1.8 to 6.0‰, excluding texturally chaotic and/or porous zircons which have δ18O values as low as 0.0‰. All low-δ18O LOVF magmas, including the caldera-forming Tuff of Leslie Gulch and Tuff of Spring Creek, are confined to the OIG, although not all zircons from within the OIG have low δ18O values. The presence and sequence of low-δ18O magmas in the LOVF and adjacent central Snake River Plain (CSRP) cannot be explained by existing caldera subsidence or pre-hotspot source models. These data, however, combined with volumetrically limited low-δ18O material in the adjacent Idaho Batholith and Basin and Range, are consistent with low-δ18O magmas

Conservation of Yellowstone Cutthroat Trout in Yellowstone National Park: A Case Study

ERIC Educational Resources Information Center

Duncan, Michael B.; Murphy, Brian R.; Zale, Alexander V.

2009-01-01

The Yellowstone cutthroat trout (YCT; "Oncorhynchus clarki bouvieri") has become a species of special concern for Yellowstone National Park (YNP) fisheries biologists. Although this subspecies formerly occupied a greater area than any other inland cutthroat trout, the current distribution of YCT is now limited to several watersheds within the…

Rapid heterogeneous assembly of multiple magma reservoirs prior to Yellowstone supereruptions.

PubMed

Wotzlaw, Jörn-Frederik; Bindeman, Ilya N; Stern, Richard A; D'Abzac, Francois-Xavier; Schaltegger, Urs

2015-09-10

Large-volume caldera-forming eruptions of silicic magmas are an important feature of continental volcanism. The timescales and mechanisms of assembly of the magma reservoirs that feed such eruptions as well as the durations and physical conditions of upper-crustal storage remain highly debated topics in volcanology. Here we explore a comprehensive data set of isotopic (O, Hf) and chemical proxies in precisely U-Pb dated zircon crystals from all caldera-forming eruptions of Yellowstone supervolcano. Analysed zircons record rapid assembly of multiple magma reservoirs by repeated injections of isotopically heterogeneous magma batches and short pre-eruption storage times of 10(3) to 10(4) years. Decoupled oxygen-hafnium isotope systematics suggest a complex source for these magmas involving variable amounts of differentiated mantle-derived melt, Archean crust and hydrothermally altered shallow-crustal rocks. These data demonstrate that complex magma reservoirs with multiple sub-chambers are a common feature of rift- and hotspot related supervolcanoes. The short duration of reservoir assembly documents rapid crustal remelting and two to three orders of magnitude higher magma production rates beneath Yellowstone compared to continental arc volcanoes. The short pre-eruption storage times further suggest that the detection of voluminous reservoirs of eruptible magma beneath active supervolcanoes may only be possible prior to an impending eruption.

Rapid heterogeneous assembly of multiple magma reservoirs prior to Yellowstone supereruptions

PubMed Central

Wotzlaw, Jörn-Frederik; Bindeman, Ilya N.; Stern, Richard A.; D’Abzac, Francois-Xavier; Schaltegger, Urs

2015-01-01

Large-volume caldera-forming eruptions of silicic magmas are an important feature of continental volcanism. The timescales and mechanisms of assembly of the magma reservoirs that feed such eruptions as well as the durations and physical conditions of upper-crustal storage remain highly debated topics in volcanology. Here we explore a comprehensive data set of isotopic (O, Hf) and chemical proxies in precisely U-Pb dated zircon crystals from all caldera-forming eruptions of Yellowstone supervolcano. Analysed zircons record rapid assembly of multiple magma reservoirs by repeated injections of isotopically heterogeneous magma batches and short pre-eruption storage times of 103 to 104 years. Decoupled oxygen-hafnium isotope systematics suggest a complex source for these magmas involving variable amounts of differentiated mantle-derived melt, Archean crust and hydrothermally altered shallow-crustal rocks. These data demonstrate that complex magma reservoirs with multiple sub-chambers are a common feature of rift- and hotspot related supervolcanoes. The short duration of reservoir assembly documents rapid crustal remelting and two to three orders of magnitude higher magma production rates beneath Yellowstone compared to continental arc volcanoes. The short pre-eruption storage times further suggest that the detection of voluminous reservoirs of eruptible magma beneath active supervolcanoes may only be possible prior to an impending eruption. PMID:26356304

The evolution of Yellowstone's magmatic system over the past 630 kyr: Insights from the crystal record

NASA Astrophysics Data System (ADS)

Stelten, M. E.

2017-12-01

The Yellowstone Plateau volcanic field in northwestern Wyoming is one of the world's largest, active silicic volcanic centers, and has produced three caldera-forming "super eruptions" over the past 2.1 Myr. As a result, the petrologic evolution of Yellowstone's magmatic system has been the focus of numerous studies over the past 60 years. Early studies at Yellowstone focused on characterizing whole-rock chemical and isotopic variations observed in magmas erupted over Yellowstone's lifetime. While these have provided important insights into the source of Yellowstone magmas and the processes controlling their compositional evolution though time, whole-rock studies are limited in their ability to identify the mechanisms and timescales of rhyolite generation. In contrast, much of the recent work at Yellowstone has focused on applying micro-analytical techniques to characterize the age and composition of phenocrysts hosted in Yellowstone rhyolites. These studies have greatly advanced our understanding of the magmatic system at Yellowstone and have provided crucial new insights into the mechanisms and timescales of rhyolite generation. In particular, recent work has focused on applying micro-analytical techniques to study the age and origin of the [1] three caldera-forming eruptions that produced the Huckleberry Ridge, Mesa Falls, Lava Creek tuffs and [2] post-Lava Creek tuff intracaldera rhyolites that compose the Plateau Rhyolite. As a result, a wealth of crystal-chemical data now exists for rhyolites erupted throughout Yellowstone's 2.1 Myr history. These data provide a unique opportunity to create a detailed reconstruction of Yellowstone's magmatic system through time. In this contribution, I integrate available age, chemical, and isotopic data for phenocrysts hosted in Yellowstone rhyolites to construct a model for the evolution of Yellowstone's magmatic system from the caldera-forming eruption of the Lava Creek tuff at ca. 0.63 Ma to the present day. In particular

Bathymetry and Geology of the Floor of Yellowstone Lake, Yellowstone National Park, Wyoming, Idaho, and Montana

USGS Publications Warehouse

Morgan, L.A.; Shanks, Wayne C.; Lee, G.K.; Webring, M.W.

2007-01-01

High-resolution, multi-beam sonar mapping of Yellowstone Lake was conducted by the U.S. Geological Survey in conjunction with the National Park Service from 1999 to 2002. Yellowstone Lake is the largest high-altitude lake in North America, at an altitude of 2,357 m with a surface area of 341 km2. More than 140 rivers and streams flow into Yellowstone Lake. The Yellowstone River, which enters at the southern end of the lake into the Southeast Arm, dominates the inflow of water and sediment (Shanks and others, 2005). The only outlet from the lake is at Fishing Bridge where the Yellowstone River flows northward discharging 375 to 4,600 cubic feet per second. The multi-beam sonar mapping occurred over a four-year period beginning in 1999 with mapping of the northern basin, continued in 2000 in West Thumb basin, in 2001 in the central basin, and in 2002 in the southern part of the lake including the Flat Mountain, South, and Southeast Arms.

Ferdinand Vandiveer Hayden and the founding of the Yellowstone National Park

USGS Publications Warehouse

,

1973-01-01

Following the Civil War, the United States intensified the exploration of her western frontiers to gain a measure of the vast lands and natural resources in the region now occupied by our Rocky Mountain States. As part of this effort, the U.S. Geological and Geographical Survey of the Territories was formed and staffed under the leadership of geologist Ferdinand Vandiveer Hayden. Originally organized under the U.S. Public Land Office in 1861, the Hayden Survey (as it was most often identified) was placed under the Secretary of the Interior in 1869 and later, under the newly created U.S. Geological Survey. Its records, maps, and photographs were then transferred to the latter agency. In commemorating the centennial of Yellowstone National Park, the U.S. Geological Survey drew upon those items deposited by Hayden to describe the early exploration of the Yellowstone area and to recount events that led to the establishment of Yellowstone as the Nation's first national park.

Quaternary Landscape Evolution and the Surface Expression of Plume-Lithosphere Interactions in the Greater Yellowstone Area.

NASA Astrophysics Data System (ADS)

Guerrero, E.; Meigs, A.; Kirby, E.

2016-12-01

Numerous investigations demonstrate that mantle convective processes such as upwelling affect the surface topography of the overriding plate and propagates through the plate accompanying its lateral motion. This deformation signal is known as transient topography and is thought to occur in the North American plate as it passes over the Yellowstone hotspot. This work explores the sensitivity of the surface of Western North America by testing the hypothesis that advection of a transient topographic wave through the North American plate is driving post-Pliocene landscape evolution of the greater Yellowstone region as the plate passes over the mantle plume. Analysis of digital elevation data reveals an asymmetric topographic swell that has an amplitude of 400-1200 m and a wavelength of 600 km which was disentangled from overlapping signals preserved in the topography. A maximum uplift rate of 0.17 mm yr-1 leads the apex of the transient topography swell by nearly 100 km. This means that presently, the western edge of the Bighorn Basin is experiencing a surface uplift rate between 0.166 and 0.302 mm yr-1 which indicates 400-800m of surface uplift in the western edge of the basin since 3 Ma and a tilt of 0.3° and 0.5° away from Yellowstone. We reinterpret the drainage evolution and erosional story of the Bighorn Basin preserved by sequences of fluvial terraces in the Bighorn Basin based on this new deformation model. We integrate this new deformation model with mapping, dating, and paleoflow data into the post-Pliocene erosional story in the basin. The change from a northward drainage to an eastward drainage through stream capture, the lateral migration of the Bighorn river away from Yellowstone, and differential incision in the basin coincides with transient topography-forced deformation.

Drainage and Landscape Evolution in the Bighorn Basin Accompanying Advection of the Yellowstone Hotspot Swell Through North America

NASA Astrophysics Data System (ADS)

Guerrero, E. F.; Meigs, A.

2012-12-01

Mantle plumes have been recognized to express themselves on the surface as long wavelength and low amplitude topographic swells. These swells are measured as positive geoid anomalies and include shorter wavelength topographic features such as volcanic edifices and pre-exisitng topography. Advection of the topographic swell is expected as the lithosphere passes over the plume uplift source. The hot spot swell occurs in the landscape as transient signal that is expressed with waxing and waning topography. Waxing topography occurs at the leading edge of the swell and is expressed as an increase in rock uplift that is preserved by rivers and landscapes. Advection of topography predicts a shift in a basin from deposition to incision, an increase in convexity of a transverse river's long profile and a lateral river migration in the direction of advection. The Yellowstone region has a strong positive geoid anomaly and the volcanic signal, which have been interpreted as the longer and shorter wavelength topographic expressions of the hot spot. These expressions of the hot spot developed in a part of North America with a compounded deformation and topographic history. Previous studies of the Yellowstone topographic swell have concentrated on the waning or trailing signal preserved in the Snake River Plain. Our project revisits the classic geomorphology study area in the Bighorn Basin of Wyoming and Montana, which is in leading edge of the swell. Present models identify the swell as having a 400 km in diameter and that it is centered on the Yellowstone caldera. If we assume advection to occur in concert with the caldera eruptive track, the Yellowstone swell has migrated to the northeast at a rate of 3 cm yr-1 and began acting on the Bighorn Basin's landscape between 3 and 2 Ma. The Bighorn Basin has an established history of a basin-wide switch from deposition to incision during the late Pliocene, yet the age control on the erosional evolution of the region is relative. This

Mantle plumes and hotspot geochemistry

NASA Astrophysics Data System (ADS)

Jackson, M. G.; Becker, T. W.; Konter, J.

2017-12-01

Ever improving global seismic models, together with expanding databases of mantle derived hotspot lavas, herald advances that relate the geochemistry of hotspots with low seismic shear-wave velocity conduits (plumes) in the mantle. Early efforts linked hotspot geochemistry with deep mantle large low velocity provinces (LLVPs) [1]. More recently, Konter and Becker (2012) [2] observed that the proportion of the C mantle component (inferred from Sr-Nd-Pb isotopes) in hotspot lavas shows an inverse relationship with seismic S-wave velocity anomalies in the shallow mantle (200 km) beneath each hotspot. They proposed that these correlations should also be made based on 3He/4He. Thus, we compare 3He/4He versus seismic S-wave velocity anomalies at 200 km depth. We find that plume-fed hotspots with the highest maximum 3He/4He (i.e., which host more of the C component) have higher hotspot buoyancy fluxes and overlie regions of lower seismic S-wave velocity (interpreted to relate to hotter mantle temperatures) at 200 km depth than hotspots that have only low 3He/4He [3]. This result complements recent work that shows an inverse relationship between maximum 3He/4He and seismic S-wave velocity anomalies in the mantle beneath the western USA [4]. The relationship between 3He/4He, shallow mantle seismic S-wave velocity anomalies, and buoyancy flux is most easily explained by a model where hotter plumes are more buoyant and entrain more of a deep, dense high 3He/4He reservoir than cooler plumes that underlie low 3He/4He hotspots. If the high 3He/4He domain is denser than other mantle components, it will be entrained only by the hottest, most buoyant plumes [3]. Such a deep, dense reservoir is ideally suited to preserving early-formed Hadean domains sampled in modern plume-fed hotspots. An important question is whether, like 3He/4He, seismic S-wave velocity anomalies in the mantle are associated with distinct heavy radiogenic isotopic compositions. C signatures are related to hot

Middle Miocene Hotspot-Related Uplift, Exhumation, and Extension north of the Snake River Plain: Evidence from Apatite (U-Th)/He Thermochronology

NASA Astrophysics Data System (ADS)

Foster, D. A.; Vogl, J.; Min, K. K.; Bricker, A.; Gelato, P. W.

2013-12-01

Passage of North America over the Yellowstone hotspot has had a profound influence on the topography of the northern Rocky Mountains. One of the most prominent topographic features is the Yellowstone crescent of high topography, which comprises two elevated shoulders bounding the eastern Snake River Plain (SRP) and converging at a topographic swell centered on the Yellowstone region. Kilometer-scale erosion has occurred locally within the topographic crescent, but it is unclear if rock exhumation is due to surface uplift surrounding the propagating hot spot, subsidence of the Snake River Plain after passage of the hot spot, or relief initiated by extension in the Northern Basin and Range Province. We have applied (U-Th/He) apatite (AHe) thermochronology to the Pioneer-Boulder Mountains (PBM) on the northern flank of the SRP, and the southern Beartooth Mountains (BM) directly north of the modern Yellowstone caldera, to constrain the timing, rates, and spatial distribution of exhumation. AHe ages from the PBM indicate that >2-3 km of exhumation occurred in the core of this topographic culmination since ~11 Ma. Age-elevation relationships suggest an exhumation rate of ~0.3 mm/yr between ~11 and 8 Ma. Eocene Challis volcanic rocks are extensively preserved and Eocene topographic highs are locally preserved to the north and south of the PBM, indicating minimal erosion adjacent to the PBM culmination. Spatial patterns of both exhumation and topography indicate that faulting was not the primary control on uplift and exhumation. Regional exhumation at 11-8 Ma was synchronous with silicic eruptions from the ~10.3 Ma Picabo volcanic field located immediately to the south and with S-tilting of the southern flank of the PBM that is likely the result of loading of the ESRP by mid-crustal mafic intrusions. AHe data from Archean rocks of the southern BM reveal Miocene-Pliocene cooling ages and include samples as young as ~2-6 Ma. Discordant single grain ages in samples with

Yellowstone and the biology of time: Photographs across a century

USGS Publications Warehouse

Meagher, Mary; Houston, Douglas B.

1999-01-01

Established in 1872, Yellowstone National Park is the oldest and one of the largest national parks in the world. In this remarkable book, scientists Mary Meagher and Douglas B. Houston present 100 sets of photographs that compare the Yellowstone of old with the park of today.Most of the photo sets include three pictures-not the usual two-with many of the original views dating back to the 1870s and 1880s. From the same photo points used by early photographers, Meagher and Houston rephotographed the scenes in the 1970s, and then, following the great fires of 1988, again in the 1990s. The result is an illuminating record of Yellowstone’s dynamic ecosystem and its changes over time.Through close analysis of the photos and reference to the vast amount of available data, Meagher and Houston describe changes in vegetation, growth of wildlife populations, the effect of beaver occupancy on wetland areas, and geothermal and elevational shifts. At the same time they point out the extent to which many sites have not changed-despite important switches in park policy and an increase in human activity.Yellowstone National Park has long been the focus of major ecological debates. Should managers allow wildfires to burn? Should the elk and bison populations be controlled? Are too many people visiting the park? Yellowstone And The Biology Of Time offers a wealth of information to help us answer these questions. A visual treasure, this book will be of value to scientists from various disciplines as well as to the many people who care about Yellowstone and other protected wilderness areas around the world.

Coefficients of productivity for Yellowstone's grizzly bear habitat

USGS Publications Warehouse

Mattson, David John; Barber, Kim; Maw, Ralene; Renkin, Roy

2004-01-01

This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977-96) on the foraging behavior of Yellowstone's bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. Coefficients were calculated for different time periods and different habitat types, specific to different parts of the Yellowstone ecosystem. Stratifications included four seasons of bear activity (spring, estrus, early hyperphagia, late hyperphagia), years when ungulate carrion and whitebark pine seed crops were abundant versus not, areas adjacent to (< 100 m) or far away from forest/nonforest edges, and areas inside or outside of ungulate winter ranges. Densities of bear activity in each region, habitat type, and time period were incorporated into calculations, controlling for the effects of proximity to human facilities. The coefficients described in this report and associated estimates of grizzly bear habitat productivity are unique among many efforts to model the conditions of bear habitat because calculations include information on energetics derived from the observed behavior of radio-marked bears.

The Blacktail Creek Tuff: an analytical and experimental study of rhyolites from the Heise volcanic field, Yellowstone hotspot system

NASA Astrophysics Data System (ADS)

Bolte, Torsten; Holtz, Francois; Almeev, Renat; Nash, Barbara

2015-02-01

The magma storage conditions of the 6.62 Ma Blacktail Creek Tuff eruption, belonging to the Heise volcanic field (6.62-4.45 Ma old) of the Yellowstone hotspot system, have been investigated by combining thermobarometric and experimental approaches. The results from different geothermometers (e.g., Fe-Ti oxides, feldspar pairs, apatite and zircon solubility, and Ti in quartz) indicate a pre-eruptive temperature in the range 825-875 °C. The temperature estimated using two-pyroxene pairs varies in a range of 810-950 °C, but the pyroxenes are probably not in equilibrium with each other, and the analytical results of melt inclusion in pyroxenes indicate a complex history for clinopyroxene, which hosts two compositionally different inclusion types. One natural Blacktail Creek Tuff rock sample has been used to determine experimentally the equilibrium phase assemblages in the pressure range 100-500 MPa and a water activity range 0.1-1.0. The experiments have been performed at fluid-present conditions, with a fluid phase composed of H2O and CO2, as well as at fluid-absent conditions. The stability of the quartzo-feldspathic phases is similar in both types of experiments, but the presence of mafic minerals such as biotite and clinopyroxene is strongly dependent on the experimental approach. Possible explanations are given for this discrepancy which may have strong impacts on the choice of appropriate experimental approaches for the determination of magma storage conditions. The comparison of the composition of natural phases and of experimentally synthesized phases confirms magma storage temperatures of 845-875 °C. Melt water contents of 1.5-2.5 wt% H2O are required to reproduce the natural Blacktail Creek Tuff mineral assemblage at these temperatures. Using the Ti-in-quartz barometer and the Qz-Ab-Or proportions of natural matrix glasses, coexisting with quartz, plagioclase and sanidine, the depth of magma storage is estimated to be in a pressure range between 130 and

The 1988 Fires in Yellowstone

ERIC Educational Resources Information Center

Dress, Abby

2008-01-01

The 1988 fires at Yellowstone National Park burned 1.4 million acres in the tri-state areas of Wyoming, Montana, and Idaho--encompassing the greater Yellowstone area--and burned some 800,000 acres within the park itself (Franke 2000). This article discusses this extraordinary fire event and contains helpful resources for bringing the science of…

Twenty Years After the 1988 Yellowstone Fires: Lessons About Disturbance and Ecosystems

USGS Publications Warehouse

Romme, W.H.; Boyce, M.S.; Gresswell, R.; Merrill, E.H.; Minshall, G.W.; Whitlock, C.; Turner, M.G.

2011-01-01

The 1988 Yellowstone fires were among the first in what has proven to be an upsurge in large severe fires in the western USA during the past 20 years. At the time of the fires, little was known about the impacts of such a large severe disturbance because scientists had had few previous opportunities to study such an event. Ecologists predicted short- and long-term effects of the 1988 fires on vegetation, biogeochemistry, primary productivity, wildlife, and aquatic ecosystems based on scientific understanding of the time. Twenty-plus years of subsequent study allow these early predictions to be evaluated. Most of the original predictions were at least partially supported, but some predictions were refuted, others nuanced, and a few postfire phenomena were entirely unexpected. Post-1988 Yellowstone studies catalyzed advances in ecology focused on the importance of spatial and temporal heterogeneity, contingent influences, and multiple interacting drivers. Post-1988 research in Yellowstone also has changed public perceptions of fire as an ecological process and attitudes towards fire management. Looking ahead to projected climate change and more frequent large fires, the well-documented ecological responses to the 1988 Yellowstone fires provide a foundation for detecting and evaluating potential changes in fire regimes of temperate mountainous regions. ?? 2011 Springer Science+Business Media, LLC.

An Overview of the Origin of A-type Silicic Magmatism Along the Snake River Plain-Yellowstone Hotspot Track

NASA Astrophysics Data System (ADS)

Christiansen, E. H.; Bindeman, I. N.; Leishman, J. R.

2015-12-01

Disparate models have been proposed for the origin of A-type rhyolites--a volumetrically minor part of modern terrestrial magmatism. But understanding the origin of A-type granites and rhyolites has significance for understanding the formation of the Earth's first silicic crust and for planetary magmatism--small volumes of such granitic materials have been found in lunar rocks, martian and asteroidal meteorites, and have been speculated to have formed on Venus. On other planets, vertical tectonics and plume-like mantle convection dominate, not the recycling of wet, oxidized plates of lithosphere as on Earth. Thus, understanding the origins of A-type silicic magma is important on multiple levels. Voluminous A-type rhyolite were produced on the Snake River Plain-Yellowstone hotspot track and provide the opportunity to better understand these important silicic magmas. Detailed petrologic studies suggest that most Snake River Plain rhyolites ultimately formed by partially melting of previously emplaced basaltic intrusions rather than by fractional crystallization of basalt or melting of Archean crust. This hypothesis is favored because of the bimodal association of rhyolite and basalt without linking intermediate compositions. In addition, incompatible element ratios (e.g., La/Nb, Pb/Ce), a lack of old zircon antecrysts, low-U inherited zircon, high ɛNd and ɛHf values, high eruption temperatures (1050°C to 850°C), low fO2 (near QFM), and H2O (as low as 1.5%), link the rhyolites to a plume-derived basaltic parent through partial melting with lesser incorporation of the Archean to Mesozoic crust that underlies the plain. Moreover, the contrast with wetter, lower temperature rhyolites that must have formed by direct crustal melting (e.g., Arbon Valley Tuff) strengthens this interpretation. Many of the rhyolites also have low δ18O values that must be produced in two stages: first by partial melting of already hydrothermally altered basalt, and subsequently in single

Post-caldera volcanism: In situ measurement of U-Pb age and oxygen isotope ratio in Pleistocene zircons from Yellowstone caldera

USGS Publications Warehouse

Bindeman, I.N.; Valley, J.W.; Wooden, J.L.; Persing, H.M.

2001-01-01

The Yellowstone Plateau volcanic field, the site of some of the largest known silicic volcanic eruptions, is the present location of NE-migrating hotspot volcanic activity. Most volcanic rocks in the Yellowstone caldera (0.6 Ma), which formed in response to the climactic eruption of 1000 km3 of Lava Creek Tuff (LCT), have unusually low oxygen isotope ratios. Ion microprobe analysis of both U-Pb age and ??18O in zircons from these low-??18O lavas reveals evidence of complex inheritance and remelting. A majority of analyzed zircons from low-??18O lavas erupted inside the Yellowstone caldera have cores that range in age from 2.4 to 0.7 Ma, significantly older than their eruption ages (0.5-0.4 Ma). These ages and the high-??18O cores indicate that these lavas are largely derived from nearly total remelting of normal-??18O Huckleberry Ridge Tuff (HRT) and other pre-LCT volcanic rocks. A post-HRT low-??18O lava shows similar inheritance of HRT-age zircons. The recycling of volcanic rocks by shallow remelting can change the water content and eruptive potential of magma. This newly proposed mechanism of intracaldera volcanism is best studied by combining in situ analysis of oxygen and U-Pb isotope ratios of individual crystals. ?? 2001 Elsevier Science B.V. All rights reserved.

Effects of water-resource development on Yellowstone River streamflow, 1928-2002

USGS Publications Warehouse

Eddy-Miller, Cheryl A.; Chase, Katherine J.

2015-01-01

Major floods in 1996 and 1997 intensified public concern about the effects of human activities on the Yellowstone River in Montana. In 1999, the Yellowstone River Conservation District Council, whose members are primarily representatives from the conservation districts bordering the main stem of the Yellowstone River, was formed to promote wise use and conservation of the Yellowstone River’s natural resources. The Yellowstone River Conservation District Council is working with the U.S. Army Corps of Engineers to understand the cumulative hydrologic effects of water-resource development in the Yellowstone River Basin. The U.S. Army Corps of Engineers, Yellowstone River Conservation District Council, and U.S. Geological Survey began cooperatively studying the Yellowstone River in 2010, publishing four reports describing streamflow information for selected sites in the Yellowstone River Basin, 1928–2002. Detailed information about the methods used, as well as summary streamflow statistics, are available in the four reports. The purpose of this fact sheet is to highlight findings from the published reports and describe the effects of water use and structures, primarily dams, on the Yellowstone River streamflow.

Geothermal Monitoring in Yellowstone National Park

NASA Astrophysics Data System (ADS)

Heasler, H. P.; Jaworowski, C.; Susong, D. D.; Lowenstern, J. B.

2007-12-01

When the first exploring parties surveyed the Yellowstone region in the late 19th Century, it was the geologic wonders - geysers, hot springs, mudpots, fumaroles - that captured their imaginations. Because of these treasures, the U.S. Congress set aside and dedicated this land of "natural curiosities" as the world's first "public pleasuring ground". Protection of Yellowstone's unique geothermal features is a key mission of Yellowstone National Park as mandated by U. S. Congressional law. In response to that mandate, the Yellowstone National Park Geology Program developed a peer-reviewed, Geothermal Monitoring Plan in 2003. With partial Congressional funding of the Plan in 2005, implementation of a scientific monitoring effort began. Yellowstone's scientific geothermal monitoring effort includes the acquisition of time-temperature data using electronic data loggers, basic water quality data, chloride flux data, estimates of radiative heat flux using airborne, thermal infrared imagery, geothermal gas monitoring, and the monitoring of groundwater wells. Time- temperature data are acquired for geysers, hot springs, steam vents, wells, rivers, and the ground. Uses of the time-temperature data include public safety, calibrating airborne thermal infrared-imagery, monitoring selected thermal features for potential hydrothermal explosions, and determining the spatial and temporal changes in thermal areas. Since 2003, upgrades of Yellowstone's stream gaging network have improved the spatial and temporal precision of the chloride flux, water quality, and groundwater components of the Geothermal Monitoring Plan. All of these methods serve both for geothermal monitoring and volcano monitoring as part of the Yellowstone Volcano Observatory. A major component of the Geothermal Monitoring Plan is remote sensing of the Yellowstone volcano and its active hydrothermal areas at various scales. The National Center for Landscape Fire Analysis at the University of Montana and the USDA

Drilling a ';super-volcano': volcanology of the proximal rhyolitic volcanic succession in the HOTSPOT deep drill hole, Idaho, Yellowstone hot-spot track

NASA Astrophysics Data System (ADS)

Knott, T.; Branney, M. J.; Christiansen, E. H.; Reichow, M. K.; McCurry, M. O.; Shervais, J. W.

2013-12-01

Project HOTSPOT seeks to understand the bimodal volcanism in the Yellowstone-Snake River large igneous province, including the magma generation and eruption history. The 1.9 km-deep Kimberly well in southern Idaho, USA, reveals a proximal mid-Miocene rhyolitic and basaltic volcanic succession marginal to the postulated Twin Falls eruptive centre. Three rhyolitic eruption-units (each we interpret to record a single eruption, based on core descriptions) are separated by basaltic lavas, palaeosols and volcaniclastic sediments, and are being dated by 40Ar-39Ar on plagioclases. Whole-rock and mineral chemical data, from each unit, has been compiled to facilitate correlation with well-studied eruption-units at more distal outcrops, where we have detailed chemical, palaeomagnetic and radiometric characterisation. Results will contribute to frequency and volume calculations for some of the most catastrophic super-eruptions in Earth history. As the volcanism is of Snake River (SR)-type and lacks typical pumice fall deposits and low-moderate grade ignimbrites, interpreting the physical origin of the units can be difficult; many SR-type rheomorphic ignimbrites are flow-banded and resemble lavas, and the distinction between these and true lavas involves interpretation of critical evidence from lower contacts (e.g., distinguishing basal lava autobreccias from peperitic contacts, which can occur at the bases of SR-type lavas and ignimbrites). The lower most eruption-unit, ';Kimberly Rhyolite 1,' is >1323 m thick (base not seen) and suggests ponding in the margin of a caldera. Few vitroclastic textures are preserved, but a rheomorphic ignimbrite origin is inferred by folded fabrics and scattered obsidian chips (2-5 mm in size) within a thick lithoidal zone, which passes sharply upwards into a 39.6 m thick vitrophyre with an autobrecciated top and it is overlain by 18 m (caldera?) lake sediments. However, lithic mesobreccia, that characterise caldera fills elsewhere, are not seen

Seismic and GPS constraints on the dynamics and kinematics of the Yellowstone volcanic field

NASA Astrophysics Data System (ADS)

Smith, R. B.; Farrell, J.; Jordan, M.; Puskas, C.; Waite, G. P.

2007-12-01

The seismically and volcanically Yellowstone hotspot resulted from interaction of a mantle plume with the overriding North America plate. This feature and related processes have modified continental lithosphere producing the Yellowstone-Snake River Plain-Newberry silicic volcanic field (YSRPN) system, with its NE volcanically active Yellowstone volcanic field. The size and accessibility of the Yellowstone area has allowed a range of geophysical experiments including earthquake monitoring and seismic and GPS imaging of this system. Seismicity is dominated by small-magnitude normal- to oblique-slip faulting earthquake swarms with shallow focal depths, maximum of ~5 km, restricted by high temperatures and a weak elastic layer. There is developing evidence of non-double couple events. Outside the caldera, earthquakes are deeper, ~20 km, and capable of M 7+ earthquakes. We integrate the results from a multi-institution experiment that recorded data from 110 seismic stations and 180 GPS stations for 1999-2004. The tomographic images confirm the existence of a low Vp-body beneath the Yellowstone caldera at depths greater than 8 km, possibly representing hot, crystallizing magma. A key result of our study is a volume of anomalously low Vp and Vp/Vs in the northwestern part of the volcanic field at shallow depths of <2.0 km. Theoretical calculations of changes in P- to S-wave velocity ratios indicate that these anomalies can be interpreted as porous, gas-filled rock. GPS-measured episodes of caldera kinematics reveals uplift and subsidence of the caldera at decadal scales with average rates of ~20 mm/yr but much higher short-term rates of up to 70 mm/yr of accelerated uplift, 2004-2007. The stress field inverted from seismic and GPS data is dominated by regional SW extension with superimposed volumetric expansion and uplift from local volcanic sources. Mantle tomography derived from integrated inversion of teleseismic and local earthquake data constrained by geoid, crustal

Seasonal gravity change at Yellowstone caldera

NASA Astrophysics Data System (ADS)

Poland, M. P.; de Zeeuw-van Dalfsen, E.

2017-12-01

The driving forces behind Yellowstone's dynamic deformation, vigorous hydrothermal system, and abundant seismicity are usually ascribed to "magmatic fluids," which could refer to magma, water, volatiles, or some combination. Deformation data alone cannot distinguish the relative importance of these fluids. Gravity measurements, however, provide an indication of mass change over time and, when combined with surface displacements, can constrain the density of subsurface fluids. Unfortunately, several decades of gravity surveys at Yellowstone have yielded ambiguous results. We suspect that the difficulty in interpreting Yellowstone gravity data is due to seasonal variations in environmental conditions—especially surface and ground water. Yellowstone gravity surveys are usually carried out at the same time of year (generally late summer) to minimize the impact of seasonality. Nevertheless, surface and subsurface water levels are not likely to be constant from year to year, given annual differences in precipitation. To assess the overall magnitude of seasonal gravity changes, we conducted gravity surveys of benchmarks in and around Yellowstone caldera in May, July, August, and October 2017. Our goal was to characterize seasonal variations due to snow melt/accumulation, changes in river and lake levels, changes in groundwater levels, and changes in hydrothermal activity. We also hope to identify sites that show little variation in gravity over the course of the 2017 surveys, as these locations may be less prone to seasonal changes and more likely to detect small variations due to magmatic processes. Preliminary examination of data collected in May and July 2017 emphasizes the importance of site location relative to sources of water. For example, a site on the banks of the Yellowstone River showed a gravity increase of several hundred microgals associated with a 50 cm increase in the river level. A high-altitude site far from rivers and lakes, in contrast, showed a

Denali Park wolf studies: Implications for Yellowstone

USGS Publications Warehouse

Mech, L. David; Meier, Thomas J.; Burch, John W.

1991-01-01

The Northern Rocky Mountain Wolf Recovery Plan approved by the U.S. Fish and Wildlife Service (1987) recommends re-establishment of wolves (Canis lupus) in Yellowstone National Park. Bills proposing wolf re-establishment in the Park have been introduced into the U.S. House and Senate. However, several questions have been raised about the possible effects of wolf re-establishment on other Yellowstone Park fauna, on human use of the Park and on human use of surrounding areas. Thus the proposed wolf re-establishment remains controversial.Information pertinent to some of the above questions is available from a current study of wolf ecology in Denali National Park and Preserve, Alaska, which we began in 1986. Although Denali Park differs from Yellowstone in several ways, it is also similar enough in important respects to provide insight into questions raised about wolf re-establishment in Yellowstone.

A random approach of test macro generation for early detection of hotspots

NASA Astrophysics Data System (ADS)

Lee, Jong-hyun; Kim, Chin; Kang, Minsoo; Hwang, Sungwook; Yang, Jae-seok; Harb, Mohammed; Al-Imam, Mohamed; Madkour, Kareem; ElManhawy, Wael; Kwan, Joe

2016-03-01

Multiple-Patterning Technology (MPT) is still the preferred choice over EUV for the advanced technology nodes, starting the 20nm node. Down the way to 7nm and 5nm nodes, Self-Aligned Multiple Patterning (SAMP) appears to be one of the effective multiple patterning techniques in terms of achieving small pitch of printed lines on wafer, yet its yield is in question. Predicting and enhancing the yield in the early stages of technology development are some of the main objectives for creating test macros on test masks. While conventional yield ramp techniques for a new technology node have relied on using designs from previous technology nodes as a starting point to identify patterns for Design of Experiment (DoE) creation, these techniques are challenging to apply in the case of introducing an MPT technique like SAMP that did not exist in previous nodes. This paper presents a new strategy for generating test structures based on random placement of unit patterns that can construct more meaningful bigger patterns. Specifications governing the relationships between those unit patterns can be adjusted to generate layout clips that look like realistic SAMP designs. A via chain can be constructed to connect the random DoE of SAMP structures through a routing layer to external pads for electrical measurement. These clips are decomposed according to the decomposition rules of the technology into the appropriate mandrel and cut masks. The decomposed clips can be tested through simulations, or electrically on silicon to discover hotspots. The hotspots can be used in optimizing the fabrication process and models to fix them. They can also be used as learning patterns for DFM deck development. By expanding the size of the randomly generated test structures, more hotspots can be detected. This should provide a faster way to enhance the yield of a new technology node.

Winter visitor use planning in Yellowstone and Grand Teton National Parks

Treesearch

John A. Sacklin; Kristin L. Legg; M. Sarah Creachbaum; Clifford L. Hawkes; George Helfrich

2000-01-01

Winter use in Yellowstone and Grand Teton National Parks increased dramatically in the 1980s and early 1990s. That increase and the emphasis on snowmobiles as the primary mode of transportation brought into focus a host of winter-related issues, including air pollution, unwanted sound, wildlife impacts and the adequacy of agency budgets, staff and infrastructure to...

More than one way to stretch: A tectonic model for extension along the plume track of the Yellowstone hotspot and adjacent Basin and Range Province

USGS Publications Warehouse

Parsons, T.; Thompson, G.A.; Smith, R.P.

1998-01-01

The eastern Snake River Plain of southern Idaho poses a paradoxical problem because it is nearly aseismic and unfaulted although it appears to be actively extending in a SW-NE direction continuously with the adjacent block-faulted Basin and Range Province. The plain represents the 100-km-wide track of the Yellowstone hotspot during the last ???16-17 m.y., and its crust has been heavily intruded by mafic magma, some of which has erupted to the surface as extensive basalt flows. Outside the plain's distinct topographic boundaries is a transition zone 30-100 km wide that has variable expression of normal faulting and magmatic activity as compared with the surrounding Basin and Range Province. Many models for the evolution of the Snake River Plain have as an integral component the suggestion that the crust of the plain became strong enough through basaltic intrusion to resist extensional deformation. However, both the boundaries of the plain and its transition zone lack any evidence of zones of strike slip or other accommodation that would allow the plain to remain intact while the Basin and Range Province extended around it; instead, the plain is coupled to its surroundings and extending with them. We estimate strain rates for the northern Basin and Range Province from various lines of evidence and show that these strains would far exceed the elastic limit of any rocks coupled to the Basin and Range; thus, if the plain is extending along with its surroundings, as the geologic evidence indicates, it must be doing so by a nearly aseismic process. Evidence of the process is provided by volcanic rift zones, indicators of subsurface dikes, which trend across the plain perpendicular to its axis. We suggest that variable magmatic strain accommodation, by emplacement and inflation of dikes perpendicular to the least principal stress in the elastic crust, allows the crust of the plain to extend nearly aseismically. Dike injection releases accumulated elastic strain but

Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future?

USGS Publications Warehouse

Lowenstern, Jacob B.; Christiansen, Robert L.; Smith, Robert B.; Morgan, Lisa A.; Heasler, Henry

2005-01-01

Yellowstone, one of the world?s largest active volcanic systems, has produced several giant volcanic eruptions in the past few million years, as well as many smaller eruptions and steam explosions. Although no eruptions of lava or volcanic ash have occurred for many thousands of years, future eruptions are likely. In the next few hundred years, hazards will most probably be limited to ongoing geyser and hot-spring activity, occasional steam explosions, and moderate to large earthquakes. To better understand Yellowstone?s volcano and earthquake hazards and to help protect the public, the U.S. Geological Survey, the University of Utah, and Yellowstone National Park formed the Yellowstone Volcano Observatory, which continuously monitors activity in the region.

Glacial and Quaternary geology of the northern Yellowstone area, Montana and Wyoming

USGS Publications Warehouse

Pierce, Kenneth L.; Licciardi, Joseph M.; Krause, Teresa R.; Whitlock, Cathy

2014-01-01

increased significantly with the development of closed subalpine forests as a result of increased fuel biomass and warmer summers. Warm dry conditions prevailed at low elevations during the early Holocene, as indicated by the presence of steppe and open mixed conifer forest. At the same time, closed subalpine forests with low fire frequency were present at higher elevations, suggesting relatively wet summer conditions. Douglas fir populations expanded throughout northern Yellowstone in the middle Holocene as a result of effectively drier conditions than before, and a decline of mesophytic plant taxa during the late Holocene imply continued drying, even though fire frequency decreased in recent millennia.

Post-glacial inflation-deflation cycles, tilting, and faulting in the Yellowstone Caldera based on Yellowstone Lake shorelines

USGS Publications Warehouse

Pierce, Kenneth L.; Cannon, Kenneth P.; Meyer, Grant A.; Trebesch, Matthew J.; Watts, Raymond D.

2002-01-01

The Yellowstone caldera, like many other later Quaternary calderas of the world, exhibits dramatic unrest. Between 1923 and 1985, the center of the Yellowstone caldera rose nearly one meter along an axis between its two resurgent domes (Pelton and Smith, 1979, Dzurisin and Yamashita, 1987). From 1985 until 1995-6, it subsided at about two cm/yr (Dzurisin and others, 1990). More recent radar interferometry studies show renewed inflation of the northeastern resurgent dome between 1995 and 1996; this inflation migrated to the southwestern resurgent dome from 1996 to 1997 (Wicks and others, 1998). We extend this record back in time using dated geomorphic evidence of postglacial Yellowstone Lake shorelines around the northern shore, and Yellowstone River levels in the outlet area. We date these shorelines using carbon isotopic and archeological methods. Following Meyer and Locke (1986) and Locke and Meyer (1994), we identify the modern shoreline as S1 (1.9 ? 0.3 m above the lake gage datum), map paleoshoreline terraces S2 to S6, and infer that the prominent shorelines were cut during intracaldera uplift episodes that produced rising water levels. Doming along the caldera axis reduces the gradient of the Yellowstone River from Le Hardys Rapids to the Yellowstone Lake outlet and ultimately causes an increase in lake level. The 1923-1985 doming is part of a longer uplift episode that has reduced the Yellowstone River gradient to a ?pool? with a drop of only 0.25 m over most of this 5 km reach. We also present new evidence that doming has caused submergence of some Holocene lake and river levels. Shoreline S5 is about 14 m above datum and estimated to be ~12.6 ka, because it post-dates a large hydrothermal explosion deposit from the Mary Bay area (MB-II) that occurred ~13 ka. S4 formed about 8 m above datum ~10.7 ka as dated by archeology and 14C, and was accompanied by offset on the Fishing Bridge fault. About 9.7 ka, the Yellowstone River eroded the ?S-meander?, followed

New challenges for grizzly bear management in Yellowstone National Park

USGS Publications Warehouse

van Manen, Frank T.; Gunther, Kerry A.

2016-01-01

A key factor contributing to the success of grizzly bear Ursus arctos conservation in the Greater Yellowstone Ecosystem has been the existence of a large protected area, Yellowstone National Park. We provide an overview of recovery efforts, how demographic parameters changed as the population increased, and how the bear management program in Yellowstone National Park has evolved to address new management challenges over time. Finally, using the management experiences in Yellowstone National Park, we present comparisons and perspectives regarding brown bear management in Shiretoko National Park.

Uplift, thermal unrest and magma intrusion at Yellowstone caldera

USGS Publications Warehouse

Wicks, Charles W.; Thatcher, Wayne; Dzurisin, Daniel; Svarc, Jerry

2006-01-01

The Yellowstone caldera, in the western United States, formed 640,000 years ago when an explosive eruption ejected 1,000 km3 of material1. It is the youngest of a series of large calderas that formed during sequential cataclysmic eruptions that began 16 million years ago in eastern Oregon and northern Nevada. The Yellowstone caldera was largely buried by rhyolite lava flows during eruptions that occurred from 150,000 to 70,000 years ago1. Since the last eruption, Yellowstone has remained restless, with high seismicity, continuing uplift/subsidence episodes with movements of 70 cm historically2 to several metres since the Pleistocene epoch3, and intense hydrothermal activity. Here we present observations of a new mode of surface deformation in Yellowstone, based on radar interferometry observations from the European Space Agency ERS-2 satellite. We infer that the observed pattern of uplift and subsidence results from variations in the movement of molten basalt into and out of the Yellowstone volcanic system.

Uplift, thermal unrest and magma intrusion at Yellowstone caldera.

PubMed

Wicks, Charles W; Thatcher, Wayne; Dzurisin, Daniel; Svarc, Jerry

2006-03-02

The Yellowstone caldera, in the western United States, formed approximately 640,000 years ago when an explosive eruption ejected approximately 1,000 km3 of material. It is the youngest of a series of large calderas that formed during sequential cataclysmic eruptions that began approximately 16 million years ago in eastern Oregon and northern Nevada. The Yellowstone caldera was largely buried by rhyolite lava flows during eruptions that occurred from approximately 150,000 to approximately 70,000 years ago. Since the last eruption, Yellowstone has remained restless, with high seismicity, continuing uplift/subsidence episodes with movements of approximately 70 cm historically to several metres since the Pleistocene epoch, and intense hydrothermal activity. Here we present observations of a new mode of surface deformation in Yellowstone, based on radar interferometry observations from the European Space Agency ERS-2 satellite. We infer that the observed pattern of uplift and subsidence results from variations in the movement of molten basalt into and out of the Yellowstone volcanic system.

Effects of exotic species on Yellowstone's grizzly bears

USGS Publications Warehouse

Reinhart, Daniel P.; Haroldson, Mark A.; Mattson, D.J.; Gunther, Kerry A.

2001-01-01

Humans have affected grizzly bears (Ursus arctos horribilis) by direct mortality, competition for space and resources, and introduction of exotic species. Exotic organisms that have affected grizzly bears in the Greater Yellowstone Area include common dandelion (Taraxacum officinale), nonnative clovers (Trifolium spp.), domesticated livestock, bovine brucellosis (Brucella abortus), lake trout (Salvelinus namaycush), and white pine blister rust (Cronartium ribicola). Some bears consume substantial amounts of dandelion and clover. However, these exotic foods provide little digested energy compared to higher-quality bear foods. Domestic livestock are of greater energetic value, but use of this food by bears often leads to conflicts with humans and subsequent increases in bear mortality. Lake trout, blister rust, and brucellosis diminish grizzly bears foods. Lake trout prey on native cutthroat trout (Oncorhynchus clarkii) in Yellowstone Lake; white pine blister rust has the potential to destroy native whitebark pine (Pinus albicaulis) stands; and management response to bovine brucellosis, a disease found in the Yellowstone bison (Bison bison) and elk (Cervus elaphus), could reduce populations of these 2 species. Exotic species will likely cause more harm than good for Yellowstone grizzly bears. Managers have few options to mitigate or contain the impacts of exotics on Yellowstone's grizzly bears. Moreover, their potential negative impacts have only begun to unfold. Exotic species may lead to the loss of substantial highquality grizzly bear foods, including much of the bison, trout, and pine seeds that Yellowstone grizzly bears currently depend upon.

Expedition: Yellowstone! A Cooperative School Outreach Project.

ERIC Educational Resources Information Center

de Golia, Jack; And Others

Designed to help upper elementary school teachers prepare for a class expedition to Yellowstone National Park, this workbook presents environmental learning activities that are also useful in schools too distant for an actual visit. Either way, the workbook aims to develop student appreciation of Yellowstone, the life in it, and the park's value…

YELLOWSTONE MAGMATIC-HYDROTHERMAL SYSTEM, U. S. A.

USGS Publications Warehouse

Fournier, R.O.; Pitt, A.M.; ,

1985-01-01

At Yellowstone National Park, the deep permeability and fluid circulation are probably controlled and maintained by repeated brittle fracture of rocks in response to local and regional stress. Focal depths of earthquakes beneath the Yellowstone caldera suggest that the transition from brittle fracture to quasi-plastic flow takes place at about 3 to 4 km. The maximum temperature likely to be attained by the hydrothermal system is 350 to 450 degree C, the convective thermal output is about 5. 5 multiplied by 10**9 watts, and the minimum average thermal flux is about 1800 mW/m**2 throughout 2,500 km**2. The average thermal gradient between the heat source and the convecting hydrothermal system must be at least 700 to 1000 degree C/km. Crystallization and partial cooling of about 0. 082 km**3 of basalt or 0. 10 km**3 of rhyolite annually could furnish the heat discharged in the hot-spring system. The Yellowstone magmatic-hydrothermal system as a whole appears to be cooling down, in spite of a relatively large rate of inflation of the Yellowstone caldera.

Using geochemistry in the greater Yellowstone area

USGS Publications Warehouse

,

1995-01-01

The greater Yellowstone area lies within adjoining parts of Wyoming, Montana, and Idaho (see figure) and includes Yellowstone and Grand Teton National Parks, parts of six national forests, plus State lands, national wildlife refuges, Bureau of Land Management lands, and private lands. This area is known worldwide for its scenic beauty, wildlife, and geologic and geothermal features.

Gray Wolves as Climate Change Buffers in Yellowstone

PubMed Central

Getz, Wayne M

2005-01-01

Understanding the mechanisms by which climate and predation patterns by top predators co-vary to affect community structure accrues added importance as humans exert growing influence over both climate and regional predator assemblages. In Yellowstone National Park, winter conditions and reintroduced gray wolves (Canis lupus) together determine the availability of winter carrion on which numerous scavenger species depend for survival and reproduction. As climate changes in Yellowstone, therefore, scavenger species may experience a dramatic reshuffling of food resources. As such, we analyzed 55 y of weather data from Yellowstone in order to determine trends in winter conditions. We found that winters are getting shorter, as measured by the number of days with snow on the ground, due to decreased snowfall and increased number of days with temperatures above freezing. To investigate synergistic effects of human and climatic alterations of species interactions, we used an empirically derived model to show that in the absence of wolves, early snow thaw leads to a substantial reduction in late-winter carrion, causing potential food bottlenecks for scavengers. In addition, by narrowing the window of time over which carrion is available and thereby creating a resource pulse, climate change likely favors scavengers that can quickly track food sources over great distances. Wolves, however, largely mitigate late-winter reduction in carrion due to earlier snow thaws. By buffering the effects of climate change on carrion availability, wolves allow scavengers to adapt to a changing environment over a longer time scale more commensurate with natural processes. This study illustrates the importance of restoring and maintaining intact food chains in the face of large-scale environmental perturbations such as climate change. PMID:15757363

Gray wolves as climate change buffers in Yellowstone.

PubMed

Wilmers, Christopher C; Getz, Wayne M

2005-04-01

Understanding the mechanisms by which climate and predation patterns by top predators co-vary to affect community structure accrues added importance as humans exert growing influence over both climate and regional predator assemblages. In Yellowstone National Park, winter conditions and reintroduced gray wolves (Canis lupus) together determine the availability of winter carrion on which numerous scavenger species depend for survival and reproduction. As climate changes in Yellowstone, therefore, scavenger species may experience a dramatic reshuffling of food resources. As such, we analyzed 55 y of weather data from Yellowstone in order to determine trends in winter conditions. We found that winters are getting shorter, as measured by the number of days with snow on the ground, due to decreased snowfall and increased number of days with temperatures above freezing. To investigate synergistic effects of human and climatic alterations of species interactions, we used an empirically derived model to show that in the absence of wolves, early snow thaw leads to a substantial reduction in late-winter carrion, causing potential food bottlenecks for scavengers. In addition, by narrowing the window of time over which carrion is available and thereby creating a resource pulse, climate change likely favors scavengers that can quickly track food sources over great distances. Wolves, however, largely mitigate late-winter reduction in carrion due to earlier snow thaws. By buffering the effects of climate change on carrion availability, wolves allow scavengers to adapt to a changing environment over a longer time scale more commensurate with natural processes. This study illustrates the importance of restoring and maintaining intact food chains in the face of large-scale environmental perturbations such as climate change.

Origins of geothermal gases at Yellowstone

USGS Publications Warehouse

Lowenstern, Jacob B.; Bergfeld, Deborah; Evans, William C.; Hunt, Andrew G.

2015-01-01

Gas emissions at the Yellowstone Plateau Volcanic Field (YPVF) reflect open-system mixing of gas species originating from diverse rock types, magmas, and crustal fluids, all combined in varying proportions at different thermal areas. Gases are not necessarily in chemical equilibrium with the waters through which they vent, especially in acid sulfate terrain where bubbles stream through stagnant acid water. Gases in adjacent thermal areas often can be differentiated by isotopic and gas ratios, and cannot be tied to one another solely by shallow processes such as boiling-induced fractionation of a parent liquid. Instead, they inherit unique gas ratios (e.g., CH4/He) from the dominant rock reservoirs where they originate, some of which underlie the Quaternary volcanic rocks. Steam/gas ratios (essentially H2O/CO2) of Yellowstone fumaroles correlate with Ar/He and N2/CO2, strongly suggesting that H2O/CO2 is controlled by addition of steam boiled from water rich in atmospheric gases. Moreover, H2O/CO2 varies systematically with geographic location, such that boiling is more enhanced in some areas than others. The δ13C and 3He/CO2 of gases reflect a dominant mantle origin for CO2 in Yellowstone gas. The mantle signature is most evident at Mud Volcano, which hosts gases with the lowest H2O/CO2, lowest CH4 concentrations and highest He isotope ratios (~16Ra), consistent with either a young subsurface intrusion or less input of crustal and meteoric gas than any other location at Yellowstone. Across the YPVF, He isotope ratios (3He/4He) inversely vary with He concentrations, and reflect varied amounts of long- stored, radiogenic He added to the magmatic endmember within the crust. Similarly, addition of CH4 from organic-rich sediments is common in the eastern thermal areas at Yellowstone. Overall, Yellowstone gases reflect addition of deep, high-temperature magmatic gas (CO2-rich), lower-temperatures crustal gases (4He- and CH4-bearing), and those gases (N2, Ne, Ar) added

Distributions of small nongame fishes in the lower Yellowstone River

USGS Publications Warehouse

Duncan, Michael B.; Bramblett, Robert G.; Zale, Alexander V.

2016-01-01

The Yellowstone River is the longest unimpounded river in the conterminous United States. It has a relatively natural flow regime, which helps maintain diverse habitats and fish assemblages uncommon in large rivers elsewhere. The lower Yellowstone River was thought to support a diverse nongame fish assemblage including several species of special concern. However, comprehensive data on the small nongame fish assemblage of the lower Yellowstone River is lacking. Therefore, we sampled the Yellowstone River downstream of its confluence with the Clark’s Fork using fyke nets and otter trawls to assess distributions and abundances of small nongame fishes. We captured 42 species (24 native and 18 nonnative) in the lower Yellowstone River with fyke nets. Native species constituted over 99% of the catch. Emerald shiners Notropis atherinoides, western silvery minnows Hybognathus argyritis, flathead chubs Platygobio gracilis, sand shiners Notropis stramineus, and longnose dace Rhinichthys cataractae composed nearly 94% of fyke net catch and were caught in every segment of the study area. We captured 24 species by otter trawling downstream of the Tongue River. Sturgeon chubs Macrhybopsis gelida, channel catfish Ictalurus punctatus, flathead chubs, stonecats Noturus flavus, and sicklefin chubs Macrhybopsis meeki composed 89% of the otter trawl catch. The upstream distributional limit of sturgeon chubs in the Yellowstone River was the Tongue River; few sicklefin chubs were captured above Intake Diversion Dam. This study not only provides biologists with baseline data for future monitoring efforts on the Yellowstone River but serves as a benchmark for management and conservation efforts in large rivers elsewhere as the Yellowstone River represents one of the best references for a naturally functioning Great Plains river.

River Chemistry and Solute Flux in Yellowstone National Park

USGS Publications Warehouse

Hurwitz, Shaul; Eagan, Sean; Heasler, Henry; Mahony, Dan; Huebner, Mark A.; Lowenstern, Jacob B.

2007-01-01

Introduction The Yellowstone Volcano Observatory (YVO) was established to 'To strengthen the long-term monitoring of volcanic and earthquake unrest in the Yellowstone National Park region'. Yellowstone National Park is underlain by a voluminous magmatic system overlain by the most active hydrothermal system on Earth. Tracking changes in water and gas chemistry is of great importance because anomalous fluxes might signal one of the earliest warnings of volcanic unrest. Because of the tremendous number, chemical diversity, and large aerial coverage of Yellowstone's thermal features, it remains daunting to monitor individual features that might serve as proxies for anomalous activity in the hydrothermal system. Sampling rivers provides some advantages, because they integrate chemical fluxes over a very large area and therefore, river fluxes may reveal large-scale spatial patterns (Hurwitz et al., 2007). In addition, based on the application of the chloride-enthalpy method (Fournier, 1979), quantifying chloride flux in rivers provides an estimate of the total heat discharge from the Yellowstone volcanic system (Norton and Friedman 1985; Fournier, 1989; Friedman and Norton, in press). Intermittent sampling of the large rivers draining Yellowstone National Park began in the 1960's (Fournier et al., 1976) and continuous sampling has been carried out since water year (1 October - 30 September) 1983 excluding water years 1995 and 1996 (Norton and Friedman, 1985, 1991; Friedman and Norton, 1990, 2000, 2007). Between 1983 and 2001 only Cl concentrations and fluxes were determined. Starting in water year 2002, the concentrations and fluxes of other anions of possible magmatic origin (F-, Br-, HCO3- , and SO42-) were also determined, and several new sampling sites were established (Hurwitz et al., 2007). The ongoing sampling and analysis of river solute flux is a key component in the current monitoring program of YVO, and it is a collaboration between the U.S. Geological Survey

Parabolic distribution of circumeastern Snake River Plain seismicity and latest Quaternary faulting: Migratory pattern and association with the Yellowstone hotspot

NASA Astrophysics Data System (ADS)

Anders, Mark H.; Geissman, John Wm.; Piety, Lucille A.; Sullivan, J. Timothy

1989-02-01

. Mapping of fault scarps and unfaulted deposits along the Grand Valley fault system shows that latest Quaternary fault scarps are restricted to the portion farthest from the eastern SRP, the southern part of the Star Valley fault. Surface displacements estimated from scarp profiles and deposit ages estimated from soil development suggest a latest Quaternary displacement rate of 0.6-1.2 mm/yr for the southern portion of the Star Valley fault. Morphologic evidence suggests that this displacement rate persisted on the Star Valley fault throughout most of the Quaternary. The latest Quaternary displacement rate calculated for the southern portion of the Star Valley fault is similar to the rate calculated for Swan Valley during the interval from 2.0 to 4.4 Ma. This similarity, together with evidence for a low Quaternary displacement rate on the fault system in Swan Valley, suggests that the location of the highest displacement rate has migrated away from the eastern SRP. Other normal faults in southeastern Idaho, northwestern Wyoming, and southwestern Montana, while less well described than the Grand Valley fault system, exhibit a similar outward migrating pattern of increased fault activity followed by quiescence. Furthermore, a temporal and spatial relationship between fault activity and the 3.5 cm/yr northeastward track of the Yellowstone hotspot is observable on the Grand Valley fault system and on other north-northwest trending late Cenozoic faults that border the eastern SRP. The temporal and spatial relationship of Miocene to present high displacement rates for other circumeastern SRP faults and the observable outwardly migrating pattern of fault activity suggest that a similar parabolic distribution of seismicity and high displacement rates was symmetrically positioned about the former position of the hotspot. Moreover, the tandem migration of the hotspot and the parabolic distribution of increased fault activity and seismicity are closely followed by a parabolic

Forecasting hotspots in East Kutai, Kutai Kartanegara, and West Kutai as early warning information

NASA Astrophysics Data System (ADS)

Wahyuningsih, S.; Goejantoro, R.; Rizki, N. A.

2018-04-01

The aims of this research are to model hotspots and forecast hotspot 2017 in East Kutai, Kutai Kartanegara and West Kutai. The methods which used in this research were Holt exponential smoothing, Holt’s additive dump trend method, Holt-Winters’ additive method, additive decomposition method, multiplicative decomposition method, Loess decomposition method and Box-Jenkins method. For smoothing techniques, additive decomposition is better than Holt’s exponential smoothing. The hotspots model using Box-Jenkins method were Autoregressive Moving Average ARIMA(1,1,0), ARIMA(0,2,1), and ARIMA(0,1,0). Comparing the results from all methods which were used in this research, and based on Root of Mean Squared Error (RMSE), show that Loess decomposition method is the best times series model, because it has the least RMSE. Thus the Loess decomposition model used to forecast the number of hotspot. The forecasting result indicatethat hotspots pattern tend to increase at the end of 2017 in Kutai Kartanegara and West Kutai, but stationary in East Kutai.

75 FR 53979 - Bison Brucellosis Remote Vaccination, Draft Environmental Impact Statement, Yellowstone National...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

... CONTACT: The Bison Ecology and Management Office, Yellowstone National Park, P.O. Box 168, Yellowstone... comments to the Bison Ecology and Management Office, Center for Resources, P.O. Box 168, Yellowstone...

Snowmelt hydrograph interpretation: Revealing watershed scale hydrologic characteristics of the Yellowstone volcanic plateau

USGS Publications Warehouse

Payton, Gardner W.; Susong, D.D.; Kip, Solomon D.; Heasler, H.

2010-01-01

Snowmelt hydrograph analysis and groundwater age dates of cool water springs on the Yellowstone volcanic plateau provide evidence of high volumes of groundwater circulation in watersheds comprised of quaternary Yellowstone volcanics. Ratios of maximum to minimum mean daily discharge and average recession indices are calculated for watersheds within and surrounding the Yellowstone volcanic plateau. A model for snowmelt recession is used to separate groundwater discharge from overland runoff, and compare groundwater systems. Hydrograph signal interpretation is corroborated with chlorofluorocarbon (CFC) and tritium concentrations in cool water springs on the Yellowstone volcanic plateau. Hydrograph parameters show a spatial pattern correlated with watershed geology. Watersheds comprised dominantly of quaternary Yellowstone volcanics are characterized by slow streamflow recession, low maximum to minimum flow ratios. Cool springs sampled within the Park contain CFC's and tritium and have apparent CFC age dates that range from about 50 years to modern. Watersheds comprised of quaternary Yellowstone volcanics have a large volume of active groundwater circulation. A large, advecting groundwater field would be the dominant mechanism for mass and energy transport in the shallow crust of the Yellowstone volcanic plateau, and thus control the Yellowstone hydrothermal system. ?? 2009 Elsevier B.V.

Long-term aspen exclosures in the Yellowstone ecosystem

Treesearch

Charles E. Kay

2001-01-01

Aspen has been declining in the Yellowstone Ecosystem for more than 80 years. Some authors have suggested that aspen is a marginal plant community in Yellowstone and that recent climatic variation has adversely affected aspen, while others contend that excessive browsing by native ungulates is primarily responsible for aspen's widespread decline. To test these...

Geologic field-trip guide to the volcanic and hydrothermal landscape of the Yellowstone Plateau

USGS Publications Warehouse

Morgan Morzel, Lisa Ann; Shanks, W. C. Pat; Lowenstern, Jacob B.; Farrell, Jamie M.; Robinson, Joel E.

2017-11-20

Yellowstone National Park, a nearly 9,000 km2 (~3,468 mi2) area, was preserved in 1872 as the world’s first national park for its unique, extraordinary, and magnificent natural features. Rimmed by a crescent of older mountainous terrain, Yellowstone National Park has at its core the Quaternary Yellowstone Plateau, an undulating landscape shaped by forces of late Cenozoic explosive and effusive volcanism, on-going tectonism, glaciation, and hydrothermal activity. The Yellowstone Caldera is the centerpiece of the Yellowstone Plateau. The Yellowstone Plateau lies at the most northeastern front of the 17-Ma Yellowstone hot spot track, one of the few places on Earth where time-transgressive processes on continental crust can be observed in the volcanic and tectonic (faulting and uplift) record at the rate and direction predicted by plate motion. Over six days, this field trip presents an intensive overview into volcanism, tectonism, and hydrothermal activity on the Yellowstone Plateau (fig. 1). Field stops are linked directly to conceptual models related to monitoring of the various volcanic, geochemical, hydrothermal, and tectonic aspects of the greater Yellowstone system. Recent interest in young and possible future volcanism at Yellowstone as well as new discoveries and synthesis of previous studies, (for example, tomographic, deformation, gas, aeromagnetic, bathymetric, and seismic surveys), provide a framework in which to discuss volcanic, hydrothermal, and seismic activity in this dynamic region.

Low δ18O zircons from the Bruneau-Jarbidge eruptive center: a key to crustal anatexis along the track of the Yellowstone hotspot

NASA Astrophysics Data System (ADS)

Cathey, H. E.; Nash, B. P.; Seligman, A. N.; Valley, J. W.; Kita, N.; Allen, C. M.; Campbell, I. H.; Vazquez, J. A.; Wooden, J. L.

2011-12-01

The Bruneau-Jarbidge eruptive center (BJEC) in the central Snake River Plain, Idaho, USA consists of the Cougar Point Tuff (CPT), a series of ten, high-temperature (900-1000°C) voluminous ignimbrites produced over the explosive phase of volcanism (12.8 - 10.5 Ma) and more than a dozen equally high-temperature rhyolite lava flows produced during the effusive phase (10.5 - 8 Ma). Spot analyses by ion microprobe of oxygen isotope ratios in 210 zircons demonstrate that all of the eruptive units of the BJEC are characterized by zircon δ18O values ≤ 2.5%, thus documenting the largest low δ18O silicic volcanic province known on Earth (>104 km3). There is no evidence for voluminous normal δ18O magmatism at the BJEC that precedes generation of low δ18O magmas as there is at other volcanic centers that generate low δ18O magmas such as Heise and Yellowstone. At these younger volcanic centers of the hotspot track, such low δ18O magmas represent ~45 % and ~20% respectively of total eruptive volumes. Zircons in all BJEC tuffs and lavas studied (23 units) document strong 18O depletion (median CPT δ18OZrc = 1.0 %, post-CPT lavas = 1.5%) with the third member of the CPT recording an excursion to minimum δ18O values (δ18OZrc= -1.8 %) in a supereruption > 2% lower than other voluminous low δ18O rhyolites known worldwide (δ18OWR ≤0.9 vs. 3.4%). Subsequent units of the CPT and lavas record a progressive recovery in δ18OZrc to ~2.5% over a ~ 4 m.y. interval (12 to 8 Ma). We present detailed evidence of unit-to-unit systematic patterns in O isotopic zoning in zircons (i.e. direction and magnitude of Δcore-rim), spectrum of δ18O in individual units, and zircon inheritance patterns established by re-analysis of spots for U-Th-Pb isotopes by LA-ICPMS and SHRIMP. In conjunction with mineral thermometry and magma compositions, these patterns are difficult to reconcile with the well-established model for "cannibalistic" low δ18O magma genesis at Heise and Yellowstone. We

The spatial regulation of meiotic recombination hotspots: are all DSB hotspots crossover hotspots?

PubMed

Serrentino, Maria-Elisabetta; Borde, Valérie

2012-07-15

A key step for the success of meiosis is programmed homologous recombination, during which crossovers, or exchange of chromosome arms, take place. Crossovers increase genetic diversity but their main function is to ensure accurate chromosome segregation. Defects in crossover number and position produce aneuploidies that represent the main cause of miscarriages and chromosomal abnormalities such as Down's syndrome. Recombination is initiated by the formation of programmed double strand breaks (DSBs), which occur preferentially at places called DSB hotspots. Among all DSBs generated, only a small fraction is repaired by crossover, the other being repaired by other homologous recombination pathways. Crossover maps have been generated in a number of organisms, defining crossover hotspots. With the availability of genome-wide maps of DSBs as well as the ability to measure genetically the repair outcome at several hotspots, it is becoming more and more clear that not all DSB hotspots behave the same for crossover formation, suggesting that chromosomal features distinguish different types of hotspots. Copyright © 2012. Published by Elsevier Inc.

Yellowstone bison fetal development and phenology of parturition

USGS Publications Warehouse

Gogan, P.J.P.; Podruzny, K.M.; Olexa, E.M.; Pac, H.I.; Frey, K.L.

2005-01-01

Knowledge of Yellowstone bison (Bison bison) parturition patterns allows managers to refine risk assessments and manage to reduce the potential for transmission of brucellosis between bison and cattle. We used historical (1941) and contemporary (1989–2002) weights and morphometric measurements of Yellowstone bison fetuses to describe fetal growth and to predict timing and synchrony of parturition. Our method was supported by agreement between our predicted parturition pattern and observed birth dates for bison that were taken in to captivity while pregnant. The distribution of parturition dates in Yellowstone bison is generally right-skewed with a majority of births in April and May and few births in the following months. Predicted timing of parturition was consistently earlier for bison of Yellowstone's northern herd than central herd. The predicted median parturition date for northern herd bison in the historical period was 3 to 12 days earlier than for 2 years in the contemporary period, respectively. Median predicted birth dates and birthing synchrony differed within herds and years in the contemporary period. For a single year of paired data, the predicted median birth date for northern herd bison was 14 days earlier than for central herd bison. This difference is coincident with an earlier onset of spring plant growth on the northern range. Our findings permit refinement of the timing of separation between Yellowstone bison and cattle intended to reduce the probability of transmission of brucellosis from bison to cattle.

Prdm9 controls activation of mammalian recombination hotspots.

PubMed

Parvanov, Emil D; Petkov, Petko M; Paigen, Kenneth

2010-02-12

Mammalian meiotic recombination, which preferentially occurs at specialized sites called hotspots, ensures the orderly segregation of meiotic chromosomes and creates genetic variation among offspring. A locus on mouse chromosome 17, which controls activation of recombination at multiple distant hotspots, has been mapped within a 181-kilobase interval, three of whose genes can be eliminated as candidates. The remaining gene, Prdm9, codes for a zinc finger containing histone H3K4 trimethylase that is expressed in early meiosis and whose deficiency results in sterility in both sexes. Mus musculus exhibits five alleles of Prdm9; human populations exhibit two predominant alleles and multiple minor alleles. The identification of Prdm9 as a protein regulating mammalian recombination hotspots initiates molecular studies of this important biological control system.

Eco-Efficient Process Improvement at the Early Development Stage: Identifying Environmental and Economic Process Hotspots for Synergetic Improvement Potential.

PubMed

Piccinno, Fabiano; Hischier, Roland; Seeger, Stefan; Som, Claudia

2018-05-15

We present here a new eco-efficiency process-improvement method to highlight combined environmental and costs hotspots of the production process of new material at a very early development stage. Production-specific and scaled-up results for life cycle assessment (LCA) and production costs are combined in a new analysis to identify synergetic improvement potentials and trade-offs, setting goals for the eco-design of new processes. The identified hotspots and bottlenecks will help users to focus on the relevant steps for improvements from an eco-efficiency perspective and potentially reduce their associated environmental impacts and production costs. Our method is illustrated with a case study of nanocellulose. The results indicate that the production route should start with carrot pomace, use heat and solvent recovery, and deactivate the enzymes with bleach instead of heat. To further improve the process, the results show that focus should be laid on the carrier polymer, sodium alginate, and the production of the GripX coating. Overall, the method shows that the underlying LCA scale-up framework is valuable for purposes beyond conventional LCA studies and is applicable at a very early stage to provide researchers with a better understanding of their production process.

Forest and Land Fire Prevention Through the Hotspot Movement Pattern Approach

NASA Astrophysics Data System (ADS)

Turmudi, T.; Kardono, P.; Hartanto, P.; Ardhitasari, Y.

2018-02-01

Indonesia has experienced a great forest fire disaster in 2015. The losses incurred were enormous. But actually the incidence of forest and land fires occurs almost every year. Various efforts were made to cope with the fire disaster. The appearance of a hotspot becomes an early indication of the fire incident both location and time. By studying the location and time of the hotspot's appearance indicates that the hotspot has certain movement patterns from year to year. This study aims to show the pattern of movement of hotspots from year to year that can be used for the prevention of forest and land fires. The method used is time series analysis of land cover and hotspot distribution. The data used were land cover data from 2005 to 2016, hotspot data from 2005 to 2016. The location of this study is the territory of Meranti Kepulauan District. The results show that the highest hotspot is 425 hotspots occurs in the shrubs and bushes. From year to year, the pattern of hotspot movement occurs in the shrubs and bushes cover. The hotspot pattern follows the direction of unused land for cultivation and is dominated by shrubs. From these results, we need to pay more attentiont for the land with the cover of shrubs adjacent to the cultivated land.

Investigation of Earthquake and Geyser Events in the Upper Geyser Basin of Yellowstone National Park from a Nodal Array

NASA Astrophysics Data System (ADS)

Garcia, S.; Karplus, M. S.; Farrell, J.; Lin, F. C.; Smith, R. B.

2017-12-01

A large seismic nodal array incorporating 133 three-component, 5-Hz geophones deployed for two weeks in early November 2015 in the Upper Geyser Basin recorded earthquake and hydrothermal activity. The University of Utah, the University of Texas at El Paso, and Yellowstone National Park collaborated to deploy Fairfield Nodal ZLand 3-C geophones concentrically centered around the Old Faithful Geyser with an average station spacing of 50 m and an aperture of 1 km. The array provided a unique dataset to investigate wave propagation through various fractures and active geysers in a hydrothermal field located over the Yellowstone hotspot. The complicated sub-surface features associated with the hydrothermal field appear to impact earthquake wave propagation in the Upper Geyser Basin and to generate seismic signals. Previous work using ambient noise cross-correlation has found an intricately fractured sub-surface that provides pathways for water beneath parts of the Upper Geyser Basin that likely feed Old Faithful and other nearby geysers and hot springs. For this study, we used the data to create visualizations of local earthquake, teleseismic earthquake, and hydrothermal events as they propagate through the array. These ground motion visualizations allow observation of wave propagation through the geyser field, which may indicate the presence of anomalous structure impacting seismic velocities and attenuation. Three teleseismic events were observed in the data, two 6.9MW earthquakes that occurred off the coast of Coquimbo, Colombia 9,000km from the array and one 6.5MW near the Aleutian Islands 4,500km from the array. All three teleseismic events observed in the data exhibited strong direct P-wave arrivals and several additional phases. One local earthquake event (2.5ML) 100km from the Upper Geyser Basin was also well-recorded by the array. Time-domain spectrograms show the dominant frequencies present in the recordings of these events. The two 6.9MW earthquakes in Chile

Climate influences on whitebark pine mortality from mountain pine beetle in the Greater Yellowstone Ecosystem

Treesearch

Polly C. Buotte; Jeffrey A. Hicke; Haiganoush K. Preisler; John T. Abatzoglou; Kenneth F. Raffa; Jesse A. Logan

2016-01-01

Extensive mortality of whitebark pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western USA, primarily from mountain pine beetle but also from other threats such as white pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark pine mortality from mountain pine beetle...

The unusual Samoan hotspot: A "hotspot highway" juxtaposed with a trench

NASA Astrophysics Data System (ADS)

Jackson, M. G.; Konter, J. G.; Koppers, A. A.

2011-12-01

Oceanic hotspots are fed by (relatively) stationary, upwelling mantle plumes that melt beneath mobile tectonic plates. This mechanism results in the generation of a linear chain of volcanoes exhibiting a clear age progression: the islands and seamounts should be increasingly older with increasing distance from the inferred location of the mantle plume. Located in the southwest Pacific, the Cook-Austral volcanic islands and seamounts were long thought to lack a clear age progression, and it has been argued that the Cook-Austral volcanic chain is an example of a hotspot not fed by a mantle plume. However, work by Chauvel et al (1997) showed that the Cook-Austral volcanoes have been generated by three distinct, co-linear mantle plumes spaced by ~1000 km, resulting in 3 overlapping hotspot tracks. Critically, the volcanoes generated by each hotspot exhibit a clear age progression that emerges from its respective plume. Using plate motion models, the reconstructed tracks of the three Cook-Austral hotspots backtrack through the region of the Pacific plate now occupied by the Samoan hotspot between 10 and 40 Ma (Konter et al., 2008). Owing to the unusual number of hotspots (Samoa is the fourth) that have been hosted in the region, we refer to this corridor of the Pacific plate as the "hotspot highway." The Samoan hotspot is burning through and thus crosscutting the trails of the older Cook-Austral hotspots. Consistent with this hypothesis, Jackson et al. (2010) reported volcanic features from the Cook-Austral hotspots in the Samoan region, including three seamounts and one atoll with geochemical affinities to the Cook-Austral hotspot. The Pacific lithosphere was likely "preconditioned" (metasomatized) by the three Cook-Australs hotspots before the arrival of the Samoan plume into the region, yet geochemical signatures associated with the Cook-Austral hotspot pedigrees are not evident in Samoan shield lavas. However, Samoan rejuvenated lavas exhibit a clear EMI (enriched

Volcanic Stratigraphy of the Quaternary Rhyolite Plateau in Yellowstone National Park

USGS Publications Warehouse

Christiansen, Robert L.; Blank, H. Richard

1972-01-01

The volcanic sequence of the Quaternary Yellowstone plateau consists of rhyolites and basalts representing three volcanic cycles. The major events of each cycle were eruption of a voluminous ash-flow sheet and formation of a large collapse caldera. Lesser events of each cycle were eruption of precaldera and postcaldera rhyolitic lava flows and marginal basaltic lavas. The three major ash-flow sheets are named and designated in this report as formations within the Yellowstone Group. The lavas are assigned to newly named formations organized around the three ash-flow sheets of the Yellowstone Group to represent the volcanic cycles. Rocks of the first volcanic cycle comprise the precaldera Junction Butte Basalt and rhyolite of Broad Creek; the Huckleberry Ridge Tuff of the Yellowstone Group; and the postcaldera Lewis Canyon Rhyolite and basalt of The Narrows. Rocks of the second volcanic cycle do not crop out within Yellowstone National Park, and only the major unit, the Mesa Falls Tuff of the Yellowstone Group, is named here. The third volcanic cycle is represented by the precaldera Mount Jackson Rhyolite and Undine Falls Basalt; the Lava Creek Tuff of the Yellowstone Group; and the postcaldera Plateau Rhyolite and five post-Lava Creek basaltic sequences. Collapse to form the compound and resurgent Yellowstone caldera was related to eruption of the Lava Creek Tuff. The Plateau Rhyolite is divided into six members - the Mallard Lake, Upper Basin, Obsidian Creek, Central Plateau, Shoshone Lake Tuff, and Roaring Mountain Members; all but the Mallard Lake postdate resurgent doming of the caldera. The basalts are divided into the Swan Lake Flat Basalt, Falls River Basalt, basalt of Mariposa Lake, Madison River Basalt, and Osprey Basalt. Sediments are intercalated in the volcanic section below the Huckleberry Ridge and Mesa Falls Tuffs and within the Junction Butte Basalt, sediments and basalts of The Narrows, Undine Falls Basalt, Plateau Rhyolite, and Osprey Basalt.

Slab-controlled Tectonomagmatism of the Pacific Northwest: A Holistic view of Columbia River, High Lava Plains, and Snake River Plain/Yellowstone Volcanism

NASA Astrophysics Data System (ADS)

James, D. E.; Fouch, M. J.; Long, M. D.; Druken, K. A.; Wagner, L. S.; Chen, C.; Carlson, R. W.

2012-12-01

We interpret post-20 Ma tectonomagmatism across the U.S. Pacific Northwest in the context of subduction related processes. While mantle plume models have long enjoyed favor as an explanation for the post 20-Ma magmatism in the region, conceptually their support has hinged almost entirely on two major features: (1) Steens/Columbia River flood basalt volcanism (plume head); and (2) The Snake River Plain/Yellowstone hotspot track (plume tail). Recent work, synthesized in this presentation, suggests that these features are more plausibly the result of mantle dynamical processes driven by southerly truncation of the Farallon/Juan de Fuca subduction zone and slab detachment along the evolving margin of western North America (Long et al., 2012; James et al., 2011). Plate reconstructions indicate that shortening of the subduction zone by the northward migration of the Mendocino triple junction resulted in a significant increase in the rate of trench retreat and slab rollback ca 20 Ma. Both numerical modeling and physical tank experiments in turn predict large-scale mantle upwelling and flow around the southern edge of the rapidly retreating slab, consistent both with the observed Steens/Columbia River flood volcanism and with the strong E-W mantle fabric observed beneath the region of the High Lava Plains of central and eastern Oregon. The High Lava Plains and Snake River Plain time-progressive volcanism began concurrently about 12 Ma, but along highly divergent tracks and characterized by strikingly different upper mantle structure. Crustal and upper mantle structure beneath the High Lava Plains exhibits evidence typical of regional extension; i.e. thin crust, flat and sharp Moho, and an uppermost mantle with low velocities but otherwise largely devoid of significant vertical structure. In contrast, the Snake River Plain exhibits ultra-low mantle velocities to depths of about 180 km along the length of the hotspot track. Seismic images of the upper mantle in the depth

A preliminary study of older hot spring alteration in Sevenmile Hole, Grand Canyon of the Yellowstone River, Yellowstone Caldera, Wyoming

USGS Publications Warehouse

Larson, Peter B.; Phillips, Allison; John, David A.; Cosca, Michael A.; Pritchard, Chad; Andersen, Allen; Manion, Jennifer

2009-01-01

Erosion in the Grand Canyon of the Yellowstone River, Yellowstone Caldera (640 ka), Wyoming, has exposed a cross section of older hydrothermal alteration in the canyon walls. The altered outcrops of the post-collapse tuff of Sulphur Creek (480 ka) extend from the canyon rim to more than 300 m beneath it. The hydrothermal minerals are zoned, with an advanced argillic alteration consisting of an association of quartz (opal) + kaolinite ± alunite ± dickite, and an argillic or potassic alteration association with quartz + illite ± adularia. Disseminated fine-grained pyrite or marcasite is ubiquitous in both alteration types. These alteration associations are characteristic products of shallow volcanic epithermal environments. The contact between the two alteration types is about 100 m beneath the rim. By analogy to other active geothermal systems including active hydrothermal springs in the Yellowstone Caldera, the transition from kaolinite to illite occurred at temperatures in the range 150 to 170 °C. An 40Ar/39Ar age on alunite of 154,000 ± 16,000 years suggests that hydrothermal activity has been ongoing since at least that time. A northwest-trending linear array of extinct and active hot spring centers in the Sevenmile Hole area implies a deeper structural control for the upflowing hydrothermal fluids. We interpret this deeper structure to be the Yellowstone Caldera ring fault that is covered by the younger tuff of Sulphur Creek. The Sevenmile Hole altered area lies at the eastern end of a band of hydrothermal centers that may mark the buried extension of the Yellowstone Caldera ring fault across the northern part of the Caldera.

The earliest low and high δ18O caldera-forming eruptions of the Yellowstone plume: Implications for the 30-40 Ma Oregon calderas and speculations on plume-triggered delaminations

NASA Astrophysics Data System (ADS)

Seligman, Angela; Bindeman, Ilya; McClaughry, Jason; Stern, Richard; Fisher, Chris

2014-11-01

We present new isotopic and trace element data for four eruptive centers in Oregon: Wildcat Mountain (40 Ma), Crooked River (32-28 Ma), Tower Mountain (32 Ma), and Mohawk River (32 Ma). The first three calderas are located too far east to be sourced through renewed subduction of the Farallon slab following accretion of the Yellowstone-produced Siletzia terrane at ~50 Ma. Basalts of the three eastern eruptive centers yield high Nb/Yb and Th/Yb ratios, indicating an enriched sublithospheric mantle source, while Mohawk River yields trace element and isotopic (δ18O and ɛHf) values that correlate with its location above a subduction zone. The voluminous rhyolitic tuffs and lavas of Crooked River (41 x 27 km) have δ18Ozircon values that include seven low δ18Ozircon units (1.8-4.5 ‰), one high δ18Ozircon unit (7.4-8.8 ‰), and two units with heterogeneous zircons (2.0-9.0 ‰), similar to younger Yellowstone-Snake River Plain rhyolites. In order to produce these low δ18O values, a large heat source, widespread hydrothermal circulation, and repeated remelting are all required. In contrast, Wildcat Mountain and Tower Mountain rocks yield high δ18Ozircon values (6.4-7.9 ‰) and normal to low ɛHfi values (5.2-12.6), indicating crustal melting of high-δ18O supracrustal rocks. We propose that these calderas were produced by the first appearance of the Yellowstone plume east of the Cascadia subduction zone, which is supported by plate reconstructions that put the Yellowstone plume under Crooked River at 32-28 Ma. Given the eastern location of these calderas along the suture of the accreted Siletzia terrane and North America, we suggest that the Yellowstone hotspot is directly responsible for magmatism at Crooked River, and for plume-assisted delamination of portions of the edge of the Blue Mountains that produced the Tower Mountain magmas, while the older Wildcat Mountain magmas are related to suture zone instabilities that were created following accretion of the

Understanding the Yellowstone magmatic system using 3D geodynamic inverse models

NASA Astrophysics Data System (ADS)

Kaus, B. J. P.; Reuber, G. S.; Popov, A.; Baumann, T.

2017-12-01

The Yellowstone magmatic system is one of the largest magmatic systems on Earth. Recent seismic tomography suggest that two distinct magma chambers exist: a shallow, presumably felsic chamber and a deeper much larger, partially molten, chamber above the Moho. Why melt stalls at different depth levels above the Yellowstone plume, whereas dikes cross-cut the whole lithosphere in the nearby Snake River Plane is unclear. Partly this is caused by our incomplete understanding of lithospheric scale melt ascent processes from the upper mantle to the shallow crust, which requires better constraints on the mechanics and material properties of the lithosphere.Here, we employ lithospheric-scale 2D and 3D geodynamic models adapted to Yellowstone to better understand magmatic processes in active arcs. The models have a number of (uncertain) input parameters such as the temperature and viscosity structure of the lithosphere, geometry and melt fraction of the magmatic system, while the melt content and rock densities are obtained by consistent thermodynamic modelling of whole rock data of the Yellowstone stratigraphy. As all of these parameters affect the dynamics of the lithosphere, we use the simulations to derive testable model predictions such as gravity anomalies, surface deformation rates and lithospheric stresses and compare them with observations. We incorporated it within an inversion method and perform 3D geodynamic inverse models of the Yellowstone magmatic system. An adjoint based method is used to derive the key model parameters and the factors that affect the stress field around the Yellowstone plume, locations of enhanced diking and melt accumulations. Results suggest that the plume and the magma chambers are connected with each other and that magma chamber overpressure is required to explain the surface displacement in phases of high activity above the Yellowstone magmatic system.

Pregnancy rates in central Yellowstone bison

USGS Publications Warehouse

Gogan, Peter J.; Russell, Robin E.; Olexa, Edward M.; Podruzny, Kevin M.

2013-01-01

Plains bison (Bison b. bison) centered on Yellowstone National Park are chronically infected with brucellosis (Brucella abortus) and culled along the park boundaries to reduce the probability of disease transmission to domestic livestock. We evaluated the relationship between pregnancy rates and age, dressed carcass weight, and serological status for brucellosis among bison culled from the central Yellowstone subpopulation during the winters of 1996–1997, 2001–2002, and 2002–2003. A model with only dressed carcass weight was the best predictor of pregnancy status for all ages with the odds of pregnancy increasing by 1.03 (95% CI = 1.02–1.04) for every 1-kg increase in weight. We found no effect of age or the serological status for brucellosis on pregnancy rates across age classes; however, we did find a positive association between age and pregnancy rates for bison ≥2 years old. Bison ≥2 years old had an overall pregnancy rate of 65% with markedly different rates in alternate ages for animals between 3 and 7 years old. Pregnancy rates were 0.50 (95% CI = 0.31–0.69) for brucellosis positive and 0.57 (95% CI = 0.34–0.78) for brucellosis negative 2- and 3-year-olds and 0.74 (95% CI = 0.60–0.85) in brucellosis positive and 0.69 (95% CI = 0.49–0.85) in brucellosis negative bison ≥4 years old. Only 1 of 21 bison <2 years old was pregnant. Our findings are important to accurately predict the effects of brucellosis on Yellowstone bison population dynamics. We review our results relative to other studies of Yellowstone bison that concluded serological status for brucellosis influences pregnancy rates.

Using monitoring data to map amphibian breeding hotspots and describe wetland vulnerability in Yellowstone and Grand Teton National Parks

USGS Publications Warehouse

Ray, Andrew M.; Legg, Kristin; Sepulveda, Adam; Hossack, Blake R.; Patla, Debra

2015-01-01

Amphibians have been selected as a “vital sign” by several National Park Service (NPS) Inventory and Monitoring (I&M) networks. An eight-year amphibian monitoring data set provided opportunities to examine spatial and temporal patterns in amphibian breeding richness and wetland desiccation across Yellowstone and Grand Teton National Parks. Amphibian breeding richness was variable across both parks and only four of 31 permanent monitoring catchments contained all four widely distributed species. Annual breeding richness was also variable through time and fluctuated by as much as 75% in some years and catchments. Wetland desiccation was also documented across the region, but alone did not explain variations in amphibian richness. High annual variability across the region emphasizes the need for multiple years of monitoring to accurately describe amphibian richness and wetland desiccation dynamics.

Paleomagnetic Tests of Global Plate Reconstructions with Fixed and Moving Hotspots

NASA Astrophysics Data System (ADS)

Andrews, D. L.; Gordon, R. G.; Horner-Johnson, B. C.

2004-12-01

Three distinct approaches have been used in prior work to estimate the motion of the Pacific basin plates relative to the surrounding continents. The first approach is to use the global plate motion circuit through Antarctica (e.g., the Pacific plate to the Antarctic plate to the African plate to the North American plate). An update to this approach is to incorporate the modest mid-Tertiary motion between East and West Antarctica estimated by Cande et al. (2000). A recently proposed second approach is to take an alternative circuit for the early Tertiary of the Pacific plate to the Australian plate to the East Antarctic plate to the African plate to the North American plate (Steinberger et al. 2004). The third approach is to assume that the hotspots in the Pacific Ocean are fixed relative to those in the Atlantic and Indian Oceans (e.g., Engebretson et al., 1986), which we recently showed indicates motion between East and West Antarctica of 800 ± 500 km near the Ross Sea Embayment. The first approach (global plate motion circuit through Antarctica) indicates very rapid motion between Pacific and Indo-Atlantic hotspots during the early Tertiary (e.g., Raymond et al. 2000). The second approach (global plate motion circuit through Australia) indicates slower, but still substantial, motion between Pacific and Indo-Atlantic hotspots (Steinberger et al. 2004). Because each of the three approaches predicts distinctly different motion between the Pacific plate and the continental plates, they can be tested with paleomagnetic data. The results of such tests indicate that the first approach leads to systematic and significant misfits between Pacific and non-Pacific early Tertiary and Late Cretaceous paleomagnetic poles. The second approach leads to slightly smaller misfits. In contrast, the circuit based on fixed hotspots brings the Pacific and non-Pacific paleomagnetic poles into consistency. Thus the paleomagnetic data decisively favor fixed hotspots over the alternative

High-resolution aeromagnetic mapping of volcanic terrain, Yellowstone National Park

USGS Publications Warehouse

Finn, C.A.; Morgan, L.A.

2002-01-01

High-resolution aeromagnetic data acquired over Yellowstone National Park (YNP) show contrasting patterns reflecting differences in rock composition, types and degree of alteration, and crustal structures that mirror the variable geology of the Yellowstone Plateau. The older, Eocene, Absaroka Volcanic Supergroup, a series of mostly altered, andesitic volcanic and volcaniclastic rocks partially exposed in mountains on the eastern margin of YNP, produces high-amplitude, positive magnetic anomalies, strongly contrasting with the less magnetic, younger, latest Cenozoic, Yellowstone Plateau Group, primarily a series of fresh and variably altered rhyolitic rocks covering most of YNP. The Yellowstone caldera is the centerpiece of the Yellowstone Plateau; part of its boundary can be identified on the aeromagnetic map as a series of discontinuous, negative magnetic anomalies that reflect faults or zones along which extensive hydrothermal alteration is localized. The large-volume rhyolitic ignimbrite deposits of the 0.63-Ma Lava Creek Tuff and the 2.1-Ma Huckleberry Ridge Tuff, which are prominent lithologies peripheral to the Yellowstone caldera, produce insignificant magnetic signatures. A zone of moderate amplitude positive anomalies coincides with the mapped extent of several post-caldera rhyolitic lavas. Linear magnetic anomalies reflect the rectilinear fault systems characteristic of resurgent domes in the center of the caldera. Peripheral to the caldera, the high-resolution aeromagnetic map clearly delineates flow unit boundaries of pre- and post-caldera basalt flows, which occur stratigraphically below the post-caldera rhyolitic lavas and are not exposed extensively at the surface. All of the hot spring and geyser basins, such as Norris, Upper and Lower Geyser Basins, West Thumb, and Gibbon, are associated with negative magnetic anomalies, reflecting hydrothermal alteration that has destroyed the magnetic susceptibility of minerals in the volcanic rocks. Within

Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming

USGS Publications Warehouse

Johnson, S.Y.; Stephenson, W.J.; Morgan, L.A.; Shanks, Wayne C.; Pierce, K.L.

2003-01-01

Yellowstone National Park is the site of one of the world's largest calderas. The abundance of geothermal and tectonic activity in and around the caldera, including historic uplift and subsidence, makes it necessary to understand active geologic processes and their associated hazards. To that end, we here use an extensive grid of high-resolution seismic reflection profiles (???450 km) to document hydrothermal and tectonic features and deposits in northern Yellowstone Lake. Sublacustrine geothermal features in northern Yellowstone Lake include two of the largest known hydrothermal explosion craters, Mary Bay and Elliott's. Mary Bay explosion breccia is distributed uniformly around the crater, whereas Elliott's crater breccia has an asymmetric distribution and forms a distinctive, ???2-km-long, hummocky lobe on the lake floor. Hydrothermal vents and low-relief domes are abundant on the lake floor; their greatest abundance is in and near explosion craters and along linear fissures. Domed areas on the lake floor that are relatively unbreached (by vents) are considered the most likely sites of future large hydrothermal explosions. Four submerged shoreline terraces along the margins of northern Yellowstone Lake add to the Holocene record or postglacial lake-level fluctuations attributed to "heavy breathing" of the Yellowstone magma reservoir and associated geothermal system. The Lake Hotel fault cuts through northwestern Yellowstone Lake and represents part of a 25-km-long distributed extensional deformation zone. Three postglacial ruptures indicate a slip rate of ???0.27 to 0.34 mm/yr. The largest (3.0 m slip) and most recent event occurred in the past ???2100 yr. Although high heat flow in the crust limits the rupture area of this fault zone, future earthquakes of magnitude ???5.3 to 6.5 are possible. Earthquakes and hydrothermal explosions have probably triggered landslides, common features around the lake margins. Few high-resolution seismic reflection surveys have

Hot Spot at Yellowstone

ERIC Educational Resources Information Center

Dress, Abby

2005-01-01

Within this huge national park (over two million acres spread across Wyoming, Montana, and Idaho) are steaming geysers, hot springs, bubbling mudpots, and fumaroles, or steam vents. Drives on the main roads of Yellowstone take tourists through the major hot attractions, which also include Norris Geyser Basin, Upper and Lower Geyser Basin, West…

Mushy Magma beneath Yellowstone

NASA Astrophysics Data System (ADS)

Chu, R.; Helmberger, D. V.; Sun, D.; Jackson, J. M.; Zhu, L.

2009-12-01

A recent prospective on the Yellowstone Caldera discounts its explosive potential based on inferences from tomographic studies on regional earthquake data which suggests a high degree of crystallization of the underlying magma body. In this study, we analyzed P-wave receiver functions recorded by broadband stations above the caldera from 100 teleseismic earthquakes between January and November 2008. After applying a number of waveform modeling tools, we obtained much lower seismic velocities than previous estimates, 2.3 km/sec (Vp) and 1.1 km/sec (Vs), with a thickness of 3.6 km in the upper crust. This shallow low velocity zone is severe enough to cause difficulties with seismic tool applications. In particular, seismologists expect teleseismic P-waves to arrive with motions up and away or down and back. Many of the observations recorded by the Yellowstone Intermountain Seismic Array, however, violate this assumption. We show that many of the first P-wave arrivals observed at seismic stations on the edge of the caldera do not travel through the magma body but have taken longer but faster paths around the edge or wrap-around phases. Three stations near the trailing edge have reversal radial-component motions, while stations near the leading edge do not. Adding our constraints on geometry, we conclude that this relatively shallow magma body has a volume of over 4,300 km3. We estimate the magma body by assuming a fluid-saturated porous material consisting of granite and a mixture of rhyolite melt and supercritical water and CO2 at temperatures of 800 oC and pressure at 5 km (0.1 GPa).Theoretical calculations of seismic wave speed suggests that the magma body beneath the Yellowstone Caldera has a porosity of 32% filled with 92% rhyolite melt and 8% water-CO2 by volume.

Wolverine in Greater Yellowstone

Treesearch

Kerry Murphy; Jason Wilmot; Jeff Copeland; Dan Tyers; John Squires

2011-01-01

The wolverine is one of the least studied carnivores in North America, particularly in the contiguous United States where it occurs at the southern extent of its range. This project documented the distribution of wolverines in the eastern portion of Yellowstone National Park and adjoining areas of national forest and their population characteristics, habitat...

Annual precipitation in the Yellowstone National Park region since AD 1173

USGS Publications Warehouse

Gray, Stephen T.; Graumlich, Lisa J.; Betancourt, Julio L.

2007-01-01

Cores and cross sections from 133 limber pine (Pinus flexilis James) and Douglas fir (Pseudotsuga menziesii (Mirbel) Franco) at four sites were used to estimate annual (July to June) precipitation in the Yellowstone National Park region for the period from AD 1173 to 1998. Examination of the long-term record shows that the early 20th century was markedly wet compared to the previous 700 yr. Extreme wet and dry years within the instrumental period fall within the range of past variability, and the magnitude of the worst-case droughts of the 20th century (AD 1930s and 1950s) was likely equaled or exceeded on numerous occasions before AD 1900. Spectral analysis showed significant decadal to multidecadal precipitation variability. At times this lower frequency variability produces strong regime-like behavior in regional precipitation, with the potential for rapid, high-amplitude switching between predominately wet and predominately dry conditions. Over multiple time scales, strong Yellowstone region precipitation anomalies were almost always associated with spatially extensive events spanning various combinations of the central and southern U.S. Rockies, the northern U.S.-Southern Canadian Rockies and the Pacific Northwest.

Annual precipitation in the Yellowstone National Park region since AD 1173

USGS Publications Warehouse

Gray, S.T.; Graumlich, L.J.; Betancourt, J.L.

2007-01-01

Cores and cross sections from 133 limber pine (Pinus flexilis James) and Douglas fir (Pseudotsuga menziesii (Mirbel) Franco) at four sites were used to estimate annual (July to June) precipitation in the Yellowstone National Park region for the period from AD 1173 to 1998. Examination of the long-term record shows that the early 20th century was markedly wet compared to the previous 700??yr. Extreme wet and dry years within the instrumental period fall within the range of past variability, and the magnitude of the worst-case droughts of the 20th century (AD 1930s and 1950s) was likely equaled or exceeded on numerous occasions before AD 1900. Spectral analysis showed significant decadal to multidecadal precipitation variability. At times this lower frequency variability produces strong regime-like behavior in regional precipitation, with the potential for rapid, high-amplitude switching between predominately wet and predominately dry conditions. Over multiple time scales, strong Yellowstone region precipitation anomalies were almost always associated with spatially extensive events spanning various combinations of the central and southern U.S. Rockies, the northern U.S.-Southern Canadian Rockies and the Pacific Northwest. ?? 2007 University of Washington.

Conservation of the Yellowstone grizzly bear

USGS Publications Warehouse

Mattson, David J.; Reid, Matthew M.

1991-01-01

We review literature relevant to the conservation of Yellowstone's grizzly bear population and appraise the bear's long-term viability. We conclude that the population is isolated and vulnerable to epidemic perturbation and that the carrying capacity of the habitat is likely to shift downward under conditions of climate change. Viability analyses based on the assumption that future habitats will closely resemble those existing at present have limited applicability; more information is needed on the autecology of important bear foods and on the implications of landscape-scale changes for bear population dynamics. Optimism over prospects of long-term persistence for Yellowstone's grizzly bears does not seem to be warranted and management of this population should be conservative and not unduly swayed on short-term positive trends.

Magma beneath Yellowstone National Park

USGS Publications Warehouse

Eaton, G.P.; Christiansen, R.L.; Iyer, H.M.; Pitt, A.M.; Mabey, D.R.; Blank, H.R.; Zietz, I.; Gettings, M.E.

1975-01-01

The Yellowstone plateau volcanic field is less than 2 million years old, lies in a region of intense tectonic and hydrothermal activity, and probably has the potential for further volcanic activity. The youngest of three volcanic cycles in the field climaxed 600,000 years ago with a voluminous ashflow eruption and the collapse of two contiguous cauldron blocks. Doming 150,000 years ago, followed by voluminous rhyolitic extrusions as recently as 70,000 years ago, and high convective heat flow at present indicate that the latest phase of volcanism may represent a new magmatic insurgence. These observations, coupled with (i) localized postglacial arcuate faulting beyond the northeast margin of the Yellowstone caldera, (ii) a major gravity low with steep bounding gradients and an amplitude regionally atypical for the elevation of the plateau, (iii) an aeromagnetic low reflecting extensive hydrothermal alteration and possibly indicating the presence of shallow material above its Curie temperature, (iv) only minor shallow seismicity within the caldera (in contrast to a high level of activity in some areas immediately outside), (v) attenuation and change of character of seismic waves crossing the caldera area, and (vi) a strong azimuthal pattern of teleseismic P-wave delays, strongly suggest that a body composed at least partly of magma underlies the region of the rhyolite plateau, including the Tertiary volcanics immediately to its northeast. The Yellowstone field represents the active end of a system of similar volcanic foci that has migrated progressively northeastward for 15 million years along the trace of the eastern Snake River Plain (8). Regional aeromagnetic patterns suggest that this course was guided by the structure of the Precambrian basement. If, as suggested by several investigators (24), the Yellowstone magma body marks a contemporary deep mantle plume, this plume, in its motion relative to the North American plate, would appear to be "navigating" along a

Recent crustal subsidence at Yellowstone Caldera, Wyoming

USGS Publications Warehouse

Dzurisin, D.; Savage, J.C.; Fournier, R.O.

1990-01-01

Following a period of net uplift at an average rate of 15??1 mm/year from 1923 to 1984, the east-central floor of Yellowstone Caldera stopped rising during 1984-1985 and then subsided 25??7 mm during 1985-1986 and an additional 35??7 mm during 1986-1987. The average horizontal strain rates in the northeast part of the caldera for the period from 1984 to 1987 were: {Mathematical expression}1 = 0.10 ?? 0.09 ??strain/year oriented N33?? E??9?? and {Mathematical expression}2 = 0.20 ?? 0.09 ??strain/year oriented N57?? W??9?? (extension reckoned positive). A best-fit elastic model of the 1985-1987 vertical and horizontal displacements in the eastern part of the caldera suggests deflation of a horizontal tabular body located 10??5 km beneath Le Hardys Rapids, i.e., within a deep hydrothermal system or within an underlying body of partly molten rhyolite. Two end-member models each explain most aspects of historical unrest at Yellowstone, including the recent reversal from uplift to subsidence. Both involve crystallization of an amount of rhyolitic magma that is compatible with the thermal energy requirements of Yellowstone's vigorous hydrothermal system. In the first model, injection of basalt near the base of the rhyolitic system is the primary cause of uplift. Higher in the magmatic system, rhyolite crystallizes and releases all of its magmatic volatiles into the shallow hydrothermal system. Uplift stops and subsidence starts whenever the supply rate of basalt is less than the subsidence rate produced by crystallization of rhyolite and associated fluid loss. In the second model, uplift is caused primarily by pressurization of the deep hydrothermal system by magmatic gas and brine that are released during crystallization of rhyolite and them trapped at lithostatic pressure beneath an impermeable self-sealed zone. Subsidence occurs during episodic hydrofracturing and injection of pore fluid from the deep lithostatic-pressure zone into a shallow hydrostatic-pressure zone

A field trip guide to the petrology of Quaternary volcanism on the Yellowstone Plateau

USGS Publications Warehouse

Vazquez, Jorge A.; Stelten, Mark; Bindeman, Ilya N.; Cooper, Kari

2017-12-19

The Yellowstone Plateau is one of the largest manifestations of silicic volcanism on Earth, and marks the youngest focus of magmatism associated with the Yellowstone Hot Spot. The earliest products of Yellowstone Hot Spot volcanism are from ~17 million years ago, but may be as old as ~32 Ma, and include contemporaneous eruption of voluminous mafic and silicic magmas, which are mostly located in the region of northwestern Nevada and southeastern Oregon. Since 17 Ma, the main locus of Yellowstone Hot Spot volcanism has migrated northeastward producing numerous silicic caldera complexes that generally remain active for ~2–4 million years, with the present-day focus being the Yellowstone Plateau. Northeastward migration of volcanism associated with the Yellowstone Hot Spot resulted in the formation of the Snake River Plain, a low relief physiographic feature extending ~750 kilometers from northern Nevada to eastern Idaho. Most of the silicic volcanic centers along the Snake River Plain have been inundated by younger basalt volcanism, but many of their ignimbrites and lava flows are exposed in the extended regions at the margins of the Snake River Plain. 

Myrmecophagy by Yellowstone grizzly bears

USGS Publications Warehouse

Mattson, D.J.

2001-01-01

I used data collected during a study of radio-marked grizzly bears (Ursus arctos horribilis) in the Yellowstone region from 1977 to 1992 to investigate myrmecophagy by this population. Although generally not an important source of energy for the bears (averaging 8 mm long) nested in logs over small ants (6 mm long) nested under stones. Optimal conditions for consumption of ants occurred on the warmest sites with ample substrate suitable for ant nests. For ants in mounds, this occurred at low elevations at non-forested sites. For ants in logs, this occurred at low elevations or on southerly aspects where there was abundant, large-diameter, well-decomposed woody debris under an open forest canopy. Grizzly bears selected moderately decomposed logs 4a??5 dm in diameter at midpoint. Ants will likely become a more important food for Yellowstone's grizzly bears as currently important foods decline, owing to disease and warming of the regional climate.

Early mantle heterogeneities in the Réunion hotspot source inferred from highly siderophile elements in cumulate xenoliths

NASA Astrophysics Data System (ADS)

Peters, Bradley J.; Day, James M. D.; Taylor, Lawrence A.

2016-08-01

remarkably homogeneous Os, Pb, and noble-gas isotopic signatures of Réunion, which plot near the convergence point of isotopic data for many hotspots, such a conclusion provides evidence for an early differentiated and subsequently isolated mantle domain that may be partially sampled by some ocean island basalts.

The duration of a Yellowstone super-eruption cycle and implications for the age of the Olduvai subchron

NASA Astrophysics Data System (ADS)

Rivera, Tiffany A.; Darata, Rachel; Lippert, Peter C.; Jicha, Brian R.; Schmitz, Mark D.

2017-12-01

Small-volume rhyolitic eruptions preceding and following a caldera-forming eruption can provide insights into the tempo of eruption cycles and timing of magmatic recharge. In this contribution, high-precision 40Ar/39Ar eruption ages were obtained on the three effusive eruptions bracketing the Huckleberry Ridge Tuff, which comprise Yellowstone's first volcanic cycle. These dates are supplemented with detailed paleomagnetic and rock magnetic analyses to resolve discrepancies with previous reported stratigraphy. The Huckleberry Ridge Tuff (2.08 Ma) was preceded by an eruption at 2.14 Ma, and followed by eruptions at 1.98 and 1.95 Ma, all of which occurred during four distinct periods of geomagnetic instability within the Matuyama chron. The first volcanic cycle of Yellowstone has now been constrained to within a 200 kyr timespan, or half of the previously proposed duration, and similar to the duration of volcanic activity for caldera-forming systems in the Jemez Volcanic Field. The maximum duration for magmatic recharge for the first Yellowstone volcanic cycle is no greater than 100 kyr, and likely closer to 40 kyr. Furthermore, the combined 40Ar/39Ar eruption ages and paleomagnetic results provide polarity anchors for the Pre-Olduvai excursion and Olduvai subchron, which are often used as tie-points in studies of early Pleistocene hominin evolution.

Dynamics of the Yellowstone hydrothermal system

USGS Publications Warehouse

Hurwitz, Shaul; Lowenstern, Jacob B.

2014-01-01

The Yellowstone Plateau Volcanic Field is characterized by extensive seismicity, episodes of uplift and subsidence, and a hydrothermal system that comprises more than 10,000 thermal features, including geysers, fumaroles, mud pots, thermal springs, and hydrothermal explosion craters. The diverse chemical and isotopic compositions of waters and gases derive from mantle, crustal, and meteoric sources and extensive water-gas-rock interaction at variable pressures and temperatures. The thermal features are host to all domains of life that utilize diverse inorganic sources of energy for metabolism. The unique and exceptional features of the hydrothermal system have attracted numerous researchers to Yellowstone beginning with the Washburn and Hayden expeditions in the 1870s. Since a seminal review published a quarter of a century ago, research in many fields has greatly advanced our understanding of the many coupled processes operating in and on the hydrothermal system. Specific advances include more refined geophysical images of the magmatic system, better constraints on the time scale of magmatic processes, characterization of fluid sources and water-rock interactions, quantitative estimates of heat and magmatic volatile fluxes, discovering and quantifying the role of thermophile microorganisms in the geochemical cycle, defining the chronology of hydrothermal explosions and their relation to glacial cycles, defining possible links between hydrothermal activity, deformation, and seismicity; quantifying geyser dynamics; and the discovery of extensive hydrothermal activity in Yellowstone Lake. Discussion of these many advances forms the basis of this review.

Classification Model for Forest Fire Hotspot Occurrences Prediction Using ANFIS Algorithm

NASA Astrophysics Data System (ADS)

Wijayanto, A. K.; Sani, O.; Kartika, N. D.; Herdiyeni, Y.

2017-01-01

This study proposed the application of data mining technique namely Adaptive Neuro-Fuzzy inference system (ANFIS) on forest fires hotspot data to develop classification models for hotspots occurrence in Central Kalimantan. Hotspot is a point that is indicated as the location of fires. In this study, hotspot distribution is categorized as true alarm and false alarm. ANFIS is a soft computing method in which a given inputoutput data set is expressed in a fuzzy inference system (FIS). The FIS implements a nonlinear mapping from its input space to the output space. The method of this study classified hotspots as target objects by correlating spatial attributes data using three folds in ANFIS algorithm to obtain the best model. The best result obtained from the 3rd fold provided low error for training (error = 0.0093676) and also low error testing result (error = 0.0093676). Attribute of distance to road is the most determining factor that influences the probability of true and false alarm where the level of human activities in this attribute is higher. This classification model can be used to develop early warning system of forest fire.

Demography of the Yellowstone grizzly bears

USGS Publications Warehouse

Pease, C.M.; Mattson, D.J.

1999-01-01

We undertook a demographic analysis of the Yellowstone grizzly bears (Ursus arctos) to identify critical environmental factors controlling grizzly bear vital rates, and thereby to help evaluate the effectiveness of past management and to identify future conservation issues. We concluded that, within the limits of uncertainty implied by the available data and our methods of data analysis, the size of the Yellowstone grizzly bear population changed little from 1975 to 1995. We found that grizzly bear mortality rates are about double in years when the whitebark pine crop fails than in mast years, and that the population probably declines when the crop fails and increases in mast years. Our model suggests that natural variation in whitebark pine crop size over the last two decades explains more of the perceived fluctuations in Yellowstone grizzly population size than do other variables. Our analysis used demographic data from 202 radio-telemetered bears followed between 1975 and 1992 and accounted for whitebark pine (Pinus albicaulis) crop failures during 1993-1995. We used a maximum likelihood method to estimate demographic parameters and used the Akaike Information Criteria to judge the significance of various independent variables. We identified no independent variables correlated with grizzly bear fecundity. In order of importance, we found that grizzly bear mortality rates are correlated with season, whitebark pine crop size (mast vs. nonmast year), sex, management-trapping status (never management-trapped vs. management-trapped once or more), and age. The mortality rate of bears that were management-trapped at least once was almost double that of bears that were never management-trapped, implying a source/sink (i.e., never management-trapped/management-trapped) structure. The rate at which bears move between the source and sink, estimated as the management-trapping rate (h), is critical to estimating the finite rate of increase, I>I?. We quantified h by

Hydrogen and bioenergetics in the Yellowstone geothermal ecosystem

PubMed Central

Spear, John R.; Walker, Jeffrey J.; McCollom, Thomas M.; Pace, Norman R.

2005-01-01

The geochemical energy budgets for high-temperature microbial ecosystems such as occur at Yellowstone National Park have been unclear. To address the relative contributions of different geochemistries to the energy demands of these ecosystems, we draw together three lines of inference. We studied the phylogenetic compositions of high-temperature (>70°C) communities in Yellowstone hot springs with distinct chemistries, conducted parallel chemical analyses, and carried out thermodynamic modeling. Results of extensive molecular analyses, taken with previous results, show that most microbial biomass in these systems, as reflected by rRNA gene abundance, is comprised of organisms of the kinds that derive energy for primary productivity from the oxidation of molecular hydrogen, H2. The apparent dominance by H2-metabolizing organisms indicates that H2 is the main source of energy for primary production in the Yellowstone high-temperature ecosystem. Hydrogen concentrations in the hot springs were measured and found to range up to >300 nM, consistent with this hypothesis. Thermodynamic modeling with environmental concentrations of potential energy sources also is consistent with the proposed microaerophilic, hydrogen-based energy economy for this geothermal ecosystem, even in the presence of high concentrations of sulfide. PMID:15671178

Volcanic calderas delineate biogeographic provinces among Yellowstone thermophiles.

PubMed

Takacs-Vesbach, Cristina; Mitchell, Kendra; Jackson-Weaver, Olan; Reysenbach, Anna-Louise

2008-07-01

It has been suggested that the distribution of microorganisms should be cosmopolitan because of their enormous capacity for dispersal. However, recent studies have revealed that geographically isolated microbial populations do exist. Geographic distance as a barrier to dispersal is most often invoked to explain these distributions. Here we show that unique and diverse sequences of the bacterial genus Sulfurihydrogenibium exist in Yellowstone thermal springs, indicating that these sites are geographically isolated. Although there was no correlation with geographic distance or the associated geochemistry of the springs, there was a strong historical signal. We found that the Yellowstone calderas, remnants of prehistoric volcanic eruptions, delineate biogeographical provinces for the Sulfurihydrogenibium within Yellowstone (chi(2): 9.7, P = 0.002). The pattern of distribution that we have detected suggests that major geological events in the past 2 million years explain more of the variation in sequence diversity in this system than do contemporary factors such as habitat or geographic distance. These findings highlight the importance of historical legacies in determining contemporary microbial distributions and suggest that the same factors that determine the biogeography of macroorganisms are also evident among bacteria.

Effects of metal mining and milling on boundary waters of Yellowstone National Park, USA

USGS Publications Warehouse

Nimmo, D.R.; Willox, M.J.; Lafrancois, T.D.; Chapman, P.L.; Brinkman, S.F.; Greene, J.C.

1998-01-01

Aquatic resources in Soda Butte Creek within Yellowstone National Park, USA, continue to be threatened by heavy metals from historical mining and milling activities that occurred upstream of the park's boundary. This includes the residue of gold, silver, and copper ore mining and processing in the early 1900s near Cooke City, Montana, just downstream of the creek's headwaters. Toxicity tests, using surrogate test species, and analyses of metals in water, sediments, and macroinvertebrate tissue were conducted from 1993 to 1995. Chronic toxicity to test species was greater in the spring than the fall and metal concentrations were elevated in the spring with copper exceeding water quality criteria in 1995. Tests with amphipods using pore water and whole sediment from the creek and copper concentrations in the tissue of macroinvertebrates and fish also suggest that copper is the metal of concern in the watershed. In order to understand current conditions in Soda Butte Creek, heavy metals, especially copper, must be considered important factors in the aquatic and riparian ecosystems within and along the creek extending into Yellowstone National Park.

SequenceLDhot: detecting recombination hotspots.

PubMed

Fearnhead, Paul

2006-12-15

There is much local variation in recombination rates across the human genome--with the majority of recombination occurring in recombination hotspots--short regions of around approximately 2 kb in length that have much higher recombination rates than neighbouring regions. Knowledge of this local variation is important, e.g. in the design and analysis of association studies for disease genes. Population genetic data, such as that generated by the HapMap project, can be used to infer the location of these hotspots. We present a new, efficient and powerful method for detecting recombination hotspots from population data. We compare our method with four current methods for detecting hotspots. It is orders of magnitude quicker, and has greater power, than two related approaches. It appears to be more powerful than HotspotFisher, though less accurate at inferring the precise positions of the hotspot. It was also more powerful than LDhot in some situations: particularly for weaker hotspots (10-40 times the background rate) when SNP density is lower (< 1/kb). Program, data sets, and full details of results are available at: http://www.maths.lancs.ac.uk/~fearnhea/Hotspot.

76 FR 31009 - BNSF Railway Company-Trackage Rights Exemption-Yellowstone Valley Railroad, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-27

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35503] BNSF Railway Company--Trackage Rights Exemption--Yellowstone Valley Railroad, Inc. Yellowstone Valley Railroad, Inc... local and overhead trackage rights to BNSF Railway Company (BNSF) over a rail line that it leases from...

A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots.

PubMed

Bejon, Philip; Williams, Thomas N; Nyundo, Christopher; Hay, Simon I; Benz, David; Gething, Peter W; Otiende, Mark; Peshu, Judy; Bashraheil, Mahfudh; Greenhouse, Bryan; Bousema, Teun; Bauni, Evasius; Marsh, Kevin; Smith, David L; Borrmann, Steffen

2014-04-24

Malaria transmission is spatially heterogeneous. This reduces the efficacy of control strategies, but focusing control strategies on clusters or 'hotspots' of transmission may be highly effective. Among 1500 homesteads in coastal Kenya we calculated (a) the fraction of febrile children with positive malaria smears per homestead, and (b) the mean age of children with malaria per homestead. These two measures were inversely correlated, indicating that children in homesteads at higher transmission acquire immunity more rapidly. This inverse correlation increased gradually with increasing spatial scale of analysis, and hotspots of febrile malaria were identified at every scale. We found hotspots within hotspots, down to the level of an individual homestead. Febrile malaria hotspots were temporally unstable, but 4 km radius hotspots could be targeted for 1 month following 1 month periods of surveillance.DOI: http://dx.doi.org/10.7554/eLife.02130.001. Copyright © 2014, Bejon et al.

Isotopic and chemical evidence concerning the genesis and contamination of basaltic and rhyolitic magma beneath the Yellowstone Plateau Volcanic Field

USGS Publications Warehouse

Hildreth, W.; Halliday, A.N.; Christiansen, R.L.

1991-01-01

Since 2.2 Ma, the Yellowstone Plateau Volcanic Field has produced ~6000 km3 of rhyolite tuffs and lavas in >60 separate eruptions, as well as ~100 km3 of tholeiitic basalt from >50 vents peripheral to the silicic focus. Intermediate eruptive products are absent. Early postcollapse rhyolites show large shifts in Nd, Sr, Pb, and O isotopic composition caused by assimilation of roof rocks and hydrothermal brines during collapse and resurgence. Younger intracaldera rhyolite lavas record partial isotopic recovery toward precaldera ratios. Thirteen extracaldera rhyolites show none of these effects and have sources independent of the subcaldera magma system. Contributions from the Archaean crust have extreme values and wide ranges of Nd-, Sr, and Pb-isotope ratios, but Yellowstone rhyolites have moderate values and limited ranges. This requires their deep-crustal sources to have been pervasively hybridized by distributed intrusion of Cenozoic basalt, most of which was probably contemporaneous with the Pliocene and Quaternary volcanism. Most Yellowstone basalts had undergone cryptic clinopyroxene fractionation in the lower crust or crust-mantle transition zone and, having also ascended through or adjacent to crustal zones of silicic-magma generation, most underwent some crustal contamination. -from Authors

Detecting fluorescence hot-spots using mosaic maps generated from multimodal endoscope imaging

NASA Astrophysics Data System (ADS)

Yang, Chenying; Soper, Timothy D.; Seibel, Eric J.

2013-03-01

Fluorescence labeled biomarkers can be detected during endoscopy to guide early cancer biopsies, such as high-grade dysplasia in Barrett's Esophagus. To enhance intraoperative visualization of the fluorescence hot-spots, a mosaicking technique was developed to create full anatomical maps of the lower esophagus and associated fluorescent hot-spots. The resultant mosaic map contains overlaid reflectance and fluorescence images. It can be used to assist biopsy and document findings. The mosaicking algorithm uses reflectance images to calculate image registration between successive frames, and apply this registration to simultaneously acquired fluorescence images. During this mosaicking process, the fluorescence signal is enhanced through multi-frame averaging. Preliminary results showed that the technique promises to enhance the detectability of the hot-spots due to enhanced fluorescence signal.

Heat flow in vapor dominated areas of the Yellowstone Plateau volcanic field: implications for the thermal budget of the Yellowstone Caldera

USGS Publications Warehouse

Hurwitz, Shaul; Harris, Robert; Werner, Cynthia Anne; Murphy, Fred

2012-01-01

Characterizing the vigor of magmatic activity in Yellowstone requires knowledge of the mechanisms and rates of heat transport between magma and the ground surface. We present results from a heat flow study in two vapor dominated, acid-sulfate thermal areas in the Yellowstone Caldera, the 0.11 km2 Obsidian Pool Thermal Area (OPTA) and the 0.25 km2 Solfatara Plateau Thermal Area (SPTA). Conductive heat flux through a low permeability layer capping large vapor reservoirs is calculated from soil temperature measurements at >600 locations and from laboratory measurements of soil properties. The conductive heat output is 3.6 ± 0.4 MW and 7.5 ± 0.4 MW from the OPTA and the SPTA, respectively. The advective heat output from soils is 1.3 ± 0.3 MW and 1.2 ± 0.3 MW from the OPTA and the SPTA, respectively and the heat output from thermal pools in the OPTA is 6.8 ± 1.4 MW. These estimates result in a total heat output of 11.8 ± 1.4 MW and 8.8 ± 0.4 MW from OPTA and SPTA, respectively. Focused zones of high heat flux in both thermal areas are roughly aligned with regional faults suggesting that faults in both areas serve as conduits for the rising acid vapor. Extrapolation of the average heat flux from the OPTA (103 ± 2 W·m−2) and SPTA (35 ± 3 W·m−2) to the ~35 km2 of vapor dominated areas in Yellowstone yields 3.6 and 1.2 GW, respectively, which is less than the total heat output transported by steam from the Yellowstone Caldera as estimated by the chloride inventory method (4.0 to 8.0 GW).

Lithospheric controls on magma composition along Earth's longest continental hotspot track.

PubMed

Davies, D R; Rawlinson, N; Iaffaldano, G; Campbell, I H

2015-09-24

Hotspots are anomalous regions of volcanism at Earth's surface that show no obvious association with tectonic plate boundaries. Classic examples include the Hawaiian-Emperor chain and the Yellowstone-Snake River Plain province. The majority are believed to form as Earth's tectonic plates move over long-lived mantle plumes: buoyant upwellings that bring hot material from Earth's deep mantle to its surface. It has long been recognized that lithospheric thickness limits the rise height of plumes and, thereby, their minimum melting pressure. It should, therefore, have a controlling influence on the geochemistry of plume-related magmas, although unambiguous evidence of this has, so far, been lacking. Here we integrate observational constraints from surface geology, geochronology, plate-motion reconstructions, geochemistry and seismology to ascertain plume melting depths beneath Earth's longest continental hotspot track, a 2,000-kilometre-long track in eastern Australia that displays a record of volcanic activity between 33 and 9 million years ago, which we call the Cosgrove track. Our analyses highlight a strong correlation between lithospheric thickness and magma composition along this track, with: (1) standard basaltic compositions in regions where lithospheric thickness is less than 110 kilometres; (2) volcanic gaps in regions where lithospheric thickness exceeds 150 kilometres; and (3) low-volume, leucitite-bearing volcanism in regions of intermediate lithospheric thickness. Trace-element concentrations from samples along this track support the notion that these compositional variations result from different degrees of partial melting, which is controlled by the thickness of overlying lithosphere. Our results place the first observational constraints on the sub-continental melting depth of mantle plumes and provide direct evidence that lithospheric thickness has a dominant influence on the volume and chemical composition of plume-derived magmas.

On the origin of brucellosis in bison of Yellowstone National Park: a review

USGS Publications Warehouse

Meagher, Mary; Meyer, Margaret E.

1994-01-01

Brucellosis caused by Brucella abortus occurs in the free-ranging bison (Bison bison) of Yellowstone and Wood Buffalo National Parks and in elk (Cervus elaphus) of the Greater Yellowstone Area. As a result of nationwide bovine brucellosis eradication programs, states and provinces proximate to the national parks are considered free of bovine brucellosis. Thus, increased attention has been focused on the wildlife within these areas as potential reservoirs for transmission to cattle. Because the national parks are mandated as natural areas, the question has been raised as to whether Brucella abortus is endogenous or exogenous to bison, particularly for Yellowstone National Park. We synthesized diverse lines of inquiry, including the evolutionary history of both bison and Brucella, wild animals as Brucella hosts, biochemical and genetic information, behavioral characteristics of host and organism, and area history to develop an evaluation of the question for the National Park Service. All lines of inquiry indicated that the organism was introduced to North America with cattle, and that the introduction into the Yellowstone bison probably was directly from cattle shortly before 1917. Fistulous withers of horses was a less likely possibility. Elk on winter feedgrounds south of Yellowstone National Park apparently acquired the disease directly from cattle. Bison presently using Grand Teton National Park probably acquired brucellosis from feedground elk.

Changing numbers of spawning cutthroat trout in tributary streams of Yellowstone Lake and estimates of grizzly bears visiting streams from DNA

USGS Publications Warehouse

Haroldson, M.A.; Gunther, K.A.; Reinhart, Daniel P.; Podruzny, S.R.; Cegelski, C.; Waits, L.; Wyman, T.C.; Smith, J.

2005-01-01

Spawning Yellowstone cutthroat trout (Oncorhynchus clarki) provide a source of highly digestible energy for grizzly bears (Ursus arctos) that visit tributary streams to Yellowstone Lake during the spring and early summer. During 1985–87, research documented grizzly bears fishing on 61% of the 124 tributary streams to the lake. Using track measurements, it was estimated that a minimum of 44 grizzly bears fished those streams annually. During 1994, non-native lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake. Lake trout are efficient predators and have the potential to reduce the native cutthroat population and negatively impact terrestrial predators that use cutthroat trout as a food resource. In 1997, we began sampling a subset of streams (n = 25) from areas of Yellowstone Lake surveyed during the previous study to determine if changes in spawner numbers or bear use had occurred. Comparisons of peak numbers and duration suggested a considerable decline between study periods in streams in the West Thumb area of the lake. The apparent decline may be due to predation by lake trout. Indices of bear use also declined on West Thumb area streams. We used DNA from hair collected near spawning streams to estimate the minimum number of bears visiting the vicinity of spawning streams. Seventy-four individual bears were identified from 429 hair samples. The annual number of individuals detected ranged from 15 in 1997 to 33 in 2000. Seventy percent of genotypes identified were represented by more than 1 sample, but only 31% of bears were documented more than 1 year of the study. Sixty-two (84%) bears were only documented in 1 segment of the lake, whereas 12 (16%) were found in 2–3 lake segments. Twenty-seven bears were identified from hair collected at multiple streams. One bear was identified on 6 streams in 2 segments of the lake and during 3 years of the study. We used encounter histories derived from DNA and the Jolly-Seber procedure in Program MARK

Warfare in biodiversity hotspots.

PubMed

Hanson, Thor; Brooks, Thomas M; Da Fonseca, Gustavo A B; Hoffmann, Michael; Lamoreux, John F; Machlis, Gary; Mittermeier, Cristina G; Mittermeier, Russell A; Pilgrim, John D

2009-06-01

Conservation efforts are only as sustainable as the social and political context within which they take place. The weakening or collapse of sociopolitical frameworks during wartime can lead to habitat destruction and the erosion of conservation policies, but in some cases, may also confer ecological benefits through altered settlement patterns and reduced resource exploitation. Over 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots, and more than 80% took place directly within hotspot areas. Less than one-third of the 34 recognized hotspots escaped significant conflict during this period, and most suffered repeated episodes of violence. This pattern was remarkably consistent over these 5 decades. Evidence from the war-torn Eastern Afromontane hotspot suggests that biodiversity conservation is improved when international nongovernmental organizations support local protected area staff and remain engaged throughout the conflict. With biodiversity hotspots concentrated in politically volatile regions, the conservation community must maintain continuous involvement during periods of war, and biodiversity conservation should be incorporated into military, reconstruction, and humanitarian programs in the world's conflict zones. ©2009 Society for Conservation Biology.

Biology, status, and management of the yellowstone cutthroat trout

USGS Publications Warehouse

Gresswell, R.E.

2011-01-01

Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri were historically distributed in the Yellowstone River drainage (Montana and Wyoming) and the Snake River drainage (Wyoming, Idaho, Utah, Nevada, and probably Washington). Individual populations evolved distinct life history characteristics in response to the diverse environments in which they were isolated after the last glaciation. Anthropogenic activities have resulted in a substantial decline (42% of the historical range is currently occupied; 28% is occupied by core [genetically unaltered] populations), but the number of extant populations, especially in headwater streams, has precluded listing of this taxon under the Endangered Species Act. Primary threats to persistence of Yellowstone cutthroat trout include (1) invasive species, resulting in hybridization, predation, disease, and interspecific competition; (2) habitat degradation from human activities such as agricultural practices, water diversions, grazing, dam construction, mineral extraction, grazing, timber harvest, and road construction; and (3) climate change, including an escalating risk of drought, wildfire, winter flooding, and rising temperatures. Extirpation of individual populations or assemblages has led to increasing isolation and fragmentation of remaining groups, which in turn raises susceptibility to the demographic influences of disturbance (both human and stochastic) and genetic factors. Primary conservation strategies include (1) preventing risks associated with invasive species by isolating populations of Yellowstone cutthroat trout and (2) connecting occupied habitats (where possible) to preserve metapopulation function and the expression of multiple life histories. Because persistence of isolated populations may be greater in the short term, current management is focused on isolating individual populations and restoring habitats; however, this approach implies that humans will act as dispersal agents if a population is

Nutritional condition of Northern Yellowstone Elk

USGS Publications Warehouse

Cook, R.C.; Cook, J.G.; Mech, L.D.

2004-01-01

Ultrasonography and body condition scoring was used to estimate nutritional condition of northern Yellowstone elk in late winter. Probability of pregnancy was related to body fat, and lactating cows had 50% less fat than non-lactating cows. For mild to normal winters, most of the elk were in good condition.

Understanding the physics of the Yellowstone magmatic system with geodynamic inverse modelling

NASA Astrophysics Data System (ADS)

Reuber, Georg; Kaus, Boris

2017-04-01

The Yellowstone magmatic system is one of the largest magmatic systems on Earth. Thus, it is important to understand the geodynamic processes that drive this very complex system on a larger scale ranging from the mantle plume up to the shallow magma chamber in the upper crust. Recent geophysical results suggest that two distinct magma chambers exist: a shallow, presumably felsic chamber and a deeper and partially molten chamber above the Moho [1]. Why melt stalls at different depth levels above the Yellowstone plume, whereas dikes cross-cut the whole lithosphere in the nearby Snake River Plane is puzzling. Therefore, we employ lithospheric-scale 2D and 3D geodynamic models to test the influence of different model parameters, such as the geometry of the magma chamber, the melt fraction, the rheological flow law, the densities and the thermal structure on their influence on the dynamics of the lithosphere. The melt content and the rock densities are obtained by consistent thermodynamic modelling of whole rock data of the Yellowstone stratigraphy. We present derivations in the stress field around the Yellowstone plume, diking areas and different melt accumulations. Our model predictions can be tested with available geophysical data (uplift rates, melt fractions, stress states, seismicity). By framing it in an inverse modelling approach we can constrain which parameters (melt fractions, viscosities, geometries) are consistent with the data and which are not. [1] Huang, Hsin-Hua, et al. "The Yellowstone magmatic system from the mantle plume to the upper crust." Science 348.6236 (2015): 773-776.

A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots

PubMed Central

Bejon, Philip; Williams, Thomas N; Nyundo, Christopher; Hay, Simon I; Benz, David; Gething, Peter W; Otiende, Mark; Peshu, Judy; Bashraheil, Mahfudh; Greenhouse, Bryan; Bousema, Teun; Bauni, Evasius; Marsh, Kevin; Smith, David L; Borrmann, Steffen

2014-01-01

Malaria transmission is spatially heterogeneous. This reduces the efficacy of control strategies, but focusing control strategies on clusters or ‘hotspots’ of transmission may be highly effective. Among 1500 homesteads in coastal Kenya we calculated (a) the fraction of febrile children with positive malaria smears per homestead, and (b) the mean age of children with malaria per homestead. These two measures were inversely correlated, indicating that children in homesteads at higher transmission acquire immunity more rapidly. This inverse correlation increased gradually with increasing spatial scale of analysis, and hotspots of febrile malaria were identified at every scale. We found hotspots within hotspots, down to the level of an individual homestead. Febrile malaria hotspots were temporally unstable, but 4 km radius hotspots could be targeted for 1 month following 1 month periods of surveillance. DOI: http://dx.doi.org/10.7554/eLife.02130.001 PMID:24843017

Hotspots in Hindsight

NASA Astrophysics Data System (ADS)

Julian, B. R.; Foulger, G. R.; Hatfield, O.; Jackson, S.; Simpson, E.; Einbeck, J.; Moore, A.

2014-12-01

Torsvik et al. [2006] suggest that the original locations of large igneous provinces ("LIPs") and kimberlites, and current locations of melting anomalies (hot-spots) lie preferentially above the margins of two Large Lower-Mantle Shear Velocity Provinces" (LLSVPs), at the base of the mantle, and that the correlation has a high significance level (> 99.9999%). They conclude the LLSVP margins are Plume-Generation Zones, and deep-mantle plumes cause hotspots and LIPs. This conclusion raises questions about what physical processes could be responsible, because, for example the LLSVPs are likely dense and not abnormally hot [Trampert et al., 2004]. The supposed LIP-hotspot-LLSVP correlations probably are examples of the "Hindsight Heresy" [Acton, 1959], of basing a statistical test upon the same data sample that led to the initial formulation of a hypothesis. In doing this, many competing hypotheses will have been considered and rejected, but this fact will not be taken into account in statistical assessments. Furthermore, probabilities will be computed for many subsets and combinations of the data, and the best-correlated cases will be cited, but this fact will not be taken into account either. Tests using independent hot-spot catalogs and mantle models suggest that the actual significance levels of the correlations are two or three orders of magnitude smaller than claimed. These tests also show that hot spots correlate well with presumably shallowly rooted features such as spreading plate boundaries. Consideration of the kimberlite dataset in the context of geological setting suggests that their apparent association with the LLSVP margins results from the fact that the Kaapvaal craton, the site of most of the kimberlites considered, lies in Southern Africa. These observations raise questions about the distinction between correlation and causation and underline the necessity to take geological factors into account. Fig: Left: Cumulative distributions of distances from

Yellowstone Park

NASA Image and Video Library

2002-10-15

Thirteen years after devastating forest fires burned over 1.6 million acres in Yellowstone National Park, the scars are still evident. In this simulated natural color ASTER image, burned areas appear gray, in contrast to the dark green of unburned forests. The image covers an area of 60 x 63 km. This image was acquired on July 2, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. http://photojournal.jpl.nasa.gov/catalog/PIA03875

Global mammal distributions, biodiversity hotspots, and conservation.

PubMed

Ceballos, Gerardo; Ehrlich, Paul R

2006-12-19

Hotspots, which have played a central role in the selection of sites for reserves, require careful rethinking. We carried out a global examination of distributions of all nonmarine mammals to determine patterns of species richness, endemism, and endangerment, and to evaluate the degree of congruence among hotspots of these three measures of diversity in mammals. We then compare congruence of hotspots in two animal groups (mammals and birds) to assess the generality of these patterns. We defined hotspots as the richest 2.5% of cells in a global equal-area grid comparable to 1 degrees latitude x 1 degrees longitude. Hotspots of species richness, "endemism," and extinction threat were noncongruent. Only 1% of cells and 16% of species were common to the three types of mammalian hotspots. Congruence increased with increases in both the geographic scope of the analysis and the percentage of cells defined as being hotspots. The within-mammal hotspot noncongruence was similar to the pattern recently found for birds. Thus, assigning global conservation priorities based on hotspots is at best a limited strategy.

Movements of a male Canada lynx crossing the greater Yellowstone Area, including highways

Treesearch

John R. Squires; Robert Oakleaf

2005-01-01

From 1999-2001, a male Canada lynx engaged in yearly exploratory movements across the greater Yellowstone area including the Teton Wilderness Area and Yellowstone National Park. For three consecutive summers, the lynx traversed a similar path in a northwesterly direction from the animal’s home range in the Wyoming Range near Big Piney, Wyoming, to as far as...

Landsat 7 - First Cloud-free Image of Yellowstone National Park

NASA Technical Reports Server (NTRS)

2002-01-01

This image of Yellowstone Lake, in the center of Yellowstone National Park, was taken by Landsat 7 on July 13, 1999. Bands 5 (1.65um),4 (.825um), and 2 (.565um) were used for red, green, and blue, respectively. Water appears blue/black, snow light blue, mature forest red/green, young forest pink, and grass and fields appear light green. Southwest of the lake is young forest that is growing in the wake of the widespread fires of 1988. For more information, see: Landsat 7 Fact Sheet Landsat 7 in Mission Control Image by Rich Irish, NASA GSFC

New Tests of the Fixed Hotspot Approximation

NASA Astrophysics Data System (ADS)

Gordon, R. G.; Andrews, D. L.; Horner-Johnson, B. C.; Kumar, R. R.

2005-05-01

We present new methods for estimating uncertainties in plate reconstructions relative to the hotspots and new tests of the fixed hotspot approximation. We find no significant motion between Pacific hotspots, on the one hand, and Indo-Atlantic hotspots, on the other, for the past ~ 50 Myr, but large and significant apparent motion before 50 Ma. Whether this motion is truly due to motion between hotspots or alternatively due to flaws in the global plate motion circuit can be tested with paleomagnetic data. These tests give results consistent with the fixed hotspot approximation and indicate significant misfits when a relative plate motion circuit through Antarctica is employed for times before 50 Ma. If all of the misfit to the global plate motion circuit is due to motion between East and West Antarctica, then that motion is 800 ± 500 km near the Ross Sea Embayment and progressively less along the Trans-Antarctic Mountains toward the Weddell Sea. Further paleomagnetic tests of the fixed hotspot approximation can be made. Cenozoic and Cretaceous paleomagnetic data from the Pacific plate, along with reconstructions of the Pacific plate relative to the hotspots, can be used to estimate an apparent polar wander (APW) path of Pacific hotspots. An APW path of Indo-Atlantic hotspots can be similarly estimated (e.g. Besse & Courtillot 2002). If both paths diverge in similar ways from the north pole of the hotspot reference frame, it would indicate that the hotspots have moved in unison relative to the spin axis, which may be attributed to true polar wander. If the two paths diverge from one another, motion between Pacific hotspots and Indo-Atlantic hotspots would be indicated. The general agreement of the two paths shows that the former is more important than the latter. The data require little or no motion between groups of hotspots, but up to ~10 mm/yr of motion is allowed within uncertainties. The results disagree, in particular, with the recent extreme interpretation of

Amphibian decline in Yellowstone National Park

Treesearch

Debra A. Patla; Charles R. Peterson; Paul Stephen Corn

2009-01-01

We conduct long-term amphibian monitoring in Yellowstone National Park (YNP) (1) and read McMenamin et al.'s article (2) with interest. This study documents decline in the extent of seasonal wetlands in the Lamar Valley of YNP during extended drought, but the conclusion, widely reported in the media, of "severe declines in 4 once-common amphibian species,...

Protein Determinants of Meiotic DNA Break Hotspots

PubMed Central

Fowler, Kyle R.; Gutiérrez-Velasco, Susana

2013-01-01

SUMMARY Meiotic recombination, crucial for proper chromosome segregation and genome evolution, is initiated by programmed DNA double-strand breaks (DSBs) in yeasts and likely all sexually reproducing species. In fission yeast, DSBs occur up to hundreds of times more frequently at special sites, called hotspots, than in other regions of the genome. What distinguishes hotspots from cold regions is an unsolved problem, although transcription factors determine some hotspots. We report the discovery that three coiled-coil proteins – Rec25, Rec27, and Mug20 – bind essentially all hotspots with unprecedented specificity even without DSB formation. These small proteins are components of linear elements, are related to synaptonemal complex proteins, and are essential for nearly all DSBs at most hotspots. Our results indicate these hotspot determinants activate or stabilize the DSB-forming protein Rec12 (Spo11 homolog) rather than promote its binding to hotspots. We propose a new paradigm for hotspot determination and crossover control by linear element proteins. PMID:23395004

Crustal deformation of the Yellowstone-Snake River Plain volcano-tectonic system-Campaign and continuous GPS observations, 1987-2004

USGS Publications Warehouse

Puskas, C.M.; Smith, R.B.; Meertens, Charles M.; Chang, W. L.

2007-01-01

The Yellowstone-Snake River Plain tectonomagmatic province resulted from Late Tertiary volcanism in western North America, producing three large, caldera-forming eruptions at the Yellowstone Plateau in the last 2 Myr. To understand the kinematics and geodynamics of this volcanic system, the University of Utah conducted seven GPS campaigns at 140 sites between 1987 and 2003 and installed a network of 15 permanent stations. GPS deployments focused on the Yellowstone caldera, the Hebgen Lake and Teton faults, and the eastern Snake River Plain. The GPS data revealed periods of uplift and subsidence of the Yellowstone caldera at rates up to 15 mm/yr. From 1987 to 1995, the caldera subsided and contracted, implying volume loss. From 1995 to 2000, deformation shifted to inflation and extension northwest of the caldera. From 2000 to 2003, uplift continued to the northwest while caldera subsidence was renewed. The GPS observations also revealed extension across the Hebgen Lake fault and fault-normal contraction across the Teton fault. Deformation rates of the Yellowstone caldera and Hebgen Lake fault were converted to equivalent total moment rates, which exceeded historic seismic moment release and late Quaternary fault slip-derived moment release by an order of magnitude. The Yellowstone caldera deformation trends were superimposed on regional southwest extension of the Yellowstone Plateau at up to 4.3 ± 0.2 mm/yr, while the eastern Snake River Plain moved southwest as a slower rate at 2.1 ± 0.2 mm/yr. This southwest extension of the Yellowstone-Snake River Plain system merged into east-west extension of the Basin-Range province. Copyright 2007 by the American Geophysical Union.

Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change

USGS Publications Warehouse

Al-Chokhachy, Robert K.; Alder, Jay R.; Hostetler, Steven W.; Gresswell, Robert E.; Shepard, Bradley

2013-01-01

We combine large observed data sets and dynamically downscaled climate data to explore historic and future (2050–2069) stream temperature changes over the topographically diverse Greater Yellowstone Ecosystem (elevation range = 824–4017 m). We link future stream temperatures with fish growth models to investigate how changing thermal regimes could influence the future distribution and persistence of native Yellowstone cutthroat trout (YCT) and competing invasive species. We find that stream temperatures during the recent decade (2000–2009) surpass the anomalously warm period of the 1930s. Climate simulations indicate air temperatures will warm by 1 °C to >3 °C over the Greater Yellowstone by mid-21st century, resulting in concomitant increases in 2050–2069 peak stream temperatures and protracted periods of warming from May to September (MJJAS). Projected changes in thermal regimes during the MJJAS growing season modify the trajectories of daily growth rates at all elevations with pronounced growth during early and late summer. For high-elevation populations, we find considerable increases in fish body mass attributable both to warming of cold-water temperatures and to extended growing seasons. During peak July to August warming, mid-21st century temperatures will cause periods of increased thermal stress, rendering some low-elevation streams less suitable for YCT. The majority (80%) of sites currently inhabited by YCT, however, display minimal loss (<10%) or positive changes in total body mass by midcentury; we attribute this response to the fact that many low-elevation populations of YCT have already been extirpated by historical changes in land use and invasions of non-native species. Our results further suggest that benefits to YCT populations due to warmer stream temperatures at currently cold sites could be offset by the interspecific effects of corresponding growth of sympatric, non-native species, underscoring the importance of developing

Litho hotspots fixing using model based algorithm

NASA Astrophysics Data System (ADS)

Zhang, Meili; Yu, Shirui; Mao, Zhibiao; Shafee, Marwa; Madkour, Kareem; ElManhawy, Wael; Kwan, Joe; Hu, Xinyi; Wan, Qijian; Du, Chunshan

2017-04-01

As technology advances, IC designs are getting more sophisticated, thus it becomes more critical and challenging to fix printability issues in the design flow. Running lithography checks before tapeout is now mandatory for designers, which creates a need for more advanced and easy-to-use techniques for fixing hotspots found after lithographic simulation without creating a new design rule checking (DRC) violation or generating a new hotspot. This paper presents a new methodology for fixing hotspots on layouts while using the same engine currently used to detect the hotspots. The fix is achieved by applying minimum movement of edges causing the hotspot, with consideration of DRC constraints. The fix is internally simulated by the lithographic simulation engine to verify that the hotspot is eliminated and that no new hotspot is generated by the new edge locations. Hotspot fix checking is enhanced by adding DRC checks to the litho-friendly design (LFD) rule file to guarantee that any fix options that violate DRC checks are removed from the output hint file. This extra checking eliminates the need to re-run both DRC and LFD checks to ensure the change successfully fixed the hotspot, which saves time and simplifies the designer's workflow. This methodology is demonstrated on industrial designs, where the fixing rate of single and dual layer hotspots is reported.

Lake Generated Microseisms at Yellowstone Lake as a Record of Ice Phenology

NASA Astrophysics Data System (ADS)

Mohd Mokhdhari, A. A.; Koper, K. D.; Burlacu, R.

2017-12-01

It has recently been shown that wave action in lakes produces microseisms, which generate noise peaks in the period range of 0.8-1.2 s as recorded by nearby seismic stations. Such noise peaks have been observed at seven seismic stations (H17A, LKWY, B208, B944, YTP, YLA, and YLT) located within 2 km of the Yellowstone Lake shoreline. Initial work using 2016 data shows that the variations in the microseism signals at Yellowstone Lake correspond with the freezing and thawing of lake ice: the seismic noise occurs more frequently in the spring, summer, and fall, and less commonly in the winter. If this can be confirmed, then lake-generated microseisms could provide a consistent measure of the freezing and melting dates of high-latitude lakes in remote areas. The seismic data would then be useful in assessing the effects of climate change on the ice phenology of those lakes. In this work, we analyze continuous seismic data recorded by the seven seismic stations around Yellowstone Lake for the years of 1995 to 2016. We generate probability distribution functions of power spectral density for each station to observe the broad elevation of energy near a period of 1 s. The time dependence of this 1-s seismic noise energy is analyzed by extracting the power spectral density at 1 s from every processed hour. The seismic observations are compared to direct measurements of the dates of ice-out and freeze-up as reported by rangers at Yellowstone National Park. We examine how accurate the seismic data are in recording the freezing and melting of Yellowstone Lake, and how the accuracy changes as a function of the number of stations used. We also examine how sensitive the results are to the particular range of periods that are analyzed.

Concentrator hot-spot testing, phase 1

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.

1987-01-01

Results of a study to determine the hot-spot susceptibility of concentrator cells, to provide a hot-spot qualification test for concentrator modules, and to provide guidelines for reducing hot-spot susceptibility are presented. Hot-spot heating occurs in a photovoltaic module when the short-circuit current of a cell is lower than the string operating current forcing the cell into reverse bias with a concurrent power dissipation. Although the basis for the concentrator module hot-spot qualification test is the test developed for flat-plate modules, issues, such as providing cell illumination, introduce additional complexities into the testing procedure. The same general guidelines apply for protecting concentrator modules from hot-spot stressing as apply to flat-plate modules. Therefore, recommendations are made on the number of bypass diodes required per given number of series cells per module or source circuit. In addition, a new method for determining the cell temperature in the laboratory or in the field is discussed.

Spatial temporal clustering for hotspot using kulldorff scan statistic method (KSS): A case in Riau Province

NASA Astrophysics Data System (ADS)

Hudjimartsu, S. A.; Djatna, T.; Ambarwari, A.; Apriliantono

2017-01-01

The forest fires in Indonesia occurs frequently in the dry season. Almost all the causes of forest fires are caused by the human activity itself. The impact of forest fires is the loss of biodiversity, pollution hazard and harm the economy of surrounding communities. To prevent fires required the method, one of them with spatial temporal clustering. Spatial temporal clustering formed grouping data so that the results of these groupings can be used as initial information on fire prevention. To analyze the fires, used hotspot data as early indicator of fire spot. Hotspot data consists of spatial and temporal dimensions can be processed using the Spatial Temporal Clustering with Kulldorff Scan Statistic (KSS). The result of this research is to the effectiveness of KSS method to cluster spatial hotspot in a case within Riau Province and produces two types of clusters, most cluster and secondary cluster. This cluster can be used as an early fire warning information.

Antipodal hotspot pairs on the earth

NASA Technical Reports Server (NTRS)

Rampino, Michael R.; Caldeira, Ken

1992-01-01

The results of statistical analyses performed on three published hotspot distributions suggest that significantly more hotspots occur as nearly antipodal pairs than is anticipated from a random distribution, or from their association with geoid highs and divergent plate margins. The observed number of antipodal hotspot pairs depends on the maximum allowable deviation from exact antipodality. At a maximum deviation of not greater than 700 km, 26 to 37 percent of hotspots form antipodal pairs in the published lists examined here, significantly more than would be expected from the general hotspot distribution. Two possible mechanisms that might create such a distribution include: (1) symmetry in the generation of mantle plumes, and (2) melting related to antipodal focusing of seismic energy from large-body impacts.

Models for the hotspot distribution

NASA Technical Reports Server (NTRS)

Jurdy, Donna M.; Stefanick, Michael

1990-01-01

Published hotspot catalogs all show a hemispheric concentration beyond what can be expected by chance. Cumulative distributions about the center of concentration are described by a power law with a fractal dimension closer to 1 than 2. Random sets of the corresponding sizes do not show this effect. A simple shift of the random sets away from a point would produce distributions similar to those of hotspot sets. The possible relation of the hotspots to the locations of ridges and subduction zones is tested using large sets of randomly-generated points to estimate areas within given distances of the plate boundaries. The probability of finding the observed number of hotspots within 10 deg of the ridges is about what is expected.

Airborne lidar detection and mapping of invasive lake trout in Yellowstone Lake.

PubMed

Roddewig, Michael R; Churnside, James H; Hauer, F Richard; Williams, Jacob; Bigelow, Patricia E; Koel, Todd M; Shaw, Joseph A

2018-05-20

The use of airborne lidar to survey fisheries has not yet been extensively applied in freshwater environments. In this study, we investigated the applicability of this technology to identify invasive lake trout (Salvelinus namaycush) in Yellowstone Lake, Yellowstone National Park, USA. Results of experimental trials conducted in 2004 and in 2015-16 provided lidar data that identified groups of fish coherent with current knowledge and models of lake trout spawning sites, and one identified site was later confirmed to have lake trout.

36 CFR 7.13 - Yellowstone National Park.

Code of Federal Regulations, 2014 CFR

2014-07-01

... license. Non-commercially guided group means a group of no more than five snowmobiles, including a non... traveling together in Yellowstone National Park on any given day or a non-commercially guided group, which... ascertain which snowmobiles in the park are part of a non-commercially guided group. (vi) Non-commercial...

Fast Paleogene Motion of the Pacific Hotspots from Revised Global Plate Circuit Constraints

NASA Technical Reports Server (NTRS)

Raymond, C.; Stock, J.; Cande, S.

2000-01-01

Major improvements in late Cretaceous-early Tertiary Pacific-Antarctica plate reconstructions, and new East-West Antarctica rotations, allow a more definitive test of the relative motion between hotspots using global plate circuit reconstructions with quantitative uncertainties.

Hydrothermal processes above the Yellowstone magma chamber: Large hydrothermal systems and large hydrothermal explosions

USGS Publications Warehouse

Morgan, L.A.; Shanks, W.C. Pat; Pierce, K.L.

2009-01-01

Hydrothermal explosions are violent and dramatic events resulting in the rapid ejection of boiling water, steam, mud, and rock fragments from source craters that range from a few meters up to more than 2 km in diameter; associated breccia can be emplaced as much as 3 to 4 km from the largest craters. Hydrothermal explosions occur where shallow interconnected reservoirs of steam- and liquid-saturated fluids with temperatures at or near the boiling curve underlie thermal fields. Sudden reduction in confi ning pressure causes fluids to fl ash to steam, resulting in signifi cant expansion, rock fragmentation, and debris ejection. In Yellowstone, hydrothermal explosions are a potentially signifi cant hazard for visitors and facilities and can damage or even destroy thermal features. The breccia deposits and associated craters formed from hydrothermal explosions are mapped as mostly Holocene (the Mary Bay deposit is older) units throughout Yellowstone National Park (YNP) and are spatially related to within the 0.64-Ma Yellowstone caldera and along the active Norris-Mammoth tectonic corridor. In Yellowstone, at least 20 large (>100 m in diameter) hydrothermal explosion craters have been identifi ed; the scale of the individual associated events dwarfs similar features in geothermal areas elsewhere in the world. Large hydrothermal explosions in Yellowstone have occurred over the past 16 ka averaging ??1 every 700 yr; similar events are likely in the future. Our studies of large hydrothermal explosion events indicate: (1) none are directly associated with eruptive volcanic or shallow intrusive events; (2) several historical explosions have been triggered by seismic events; (3) lithic clasts and comingled matrix material that form hydrothermal explosion deposits are extensively altered, indicating that explosions occur in areas subjected to intense hydrothermal processes; (4) many lithic clasts contained in explosion breccia deposits preserve evidence of repeated fracturing

Mapping vegetation in Yellowstone National Park using spectral feature analysis of AVIRIS data

USGS Publications Warehouse

Kokaly, Raymond F.; Despain, Don G.; Clark, Roger N.; Livo, K. Eric

2003-01-01

Knowledge of the distribution of vegetation on the landscape can be used to investigate ecosystem functioning. The sizes and movements of animal populations can be linked to resources provided by different plant species. This paper demonstrates the application of imaging spectroscopy to the study of vegetation in Yellowstone National Park (Yellowstone) using spectral feature analysis of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data, acquired on August 7, 1996, were calibrated to surface reflectance using a radiative transfer model and field reflectance measurements of a ground calibration site. A spectral library of canopy reflectance signatures was created by averaging pixels of the calibrated AVIRIS data over areas of known forest and nonforest vegetation cover types in Yellowstone. Using continuum removal and least squares fitting algorithms in the US Geological Survey's Tetracorder expert system, the distributions of these vegetation types were determined by comparing the absorption features of vegetation in the spectral library with the spectra from the AVIRIS data. The 0.68 μm chlorophyll absorption feature and leaf water absorption features, centered near 0.98 and 1.20 μm, were analyzed. Nonforest cover types of sagebrush, grasslands, willows, sedges, and other wetland vegetation were mapped in the Lamar Valley of Yellowstone. Conifer cover types of lodgepole pine, whitebark pine, Douglas fir, and mixed Engelmann spruce/subalpine fir forests were spectrally discriminated and their distributions mapped in the AVIRIS images. In the Mount Washburn area of Yellowstone, a comparison of the AVIRIS map of forest cover types to a map derived from air photos resulted in an overall agreement of 74.1% (kappa statistic=0.62).

Microbial micropatches within microbial hotspots.

PubMed

Dann, Lisa M; McKerral, Jody C; Smith, Renee J; Tobe, Shanan S; Paterson, James S; Seymour, Justin R; Oliver, Rod L; Mitchell, James G

2018-01-01

The spatial distributions of organism abundance and diversity are often heterogeneous. This includes the sub-centimetre distributions of microbes, which have 'hotspots' of high abundance, and 'coldspots' of low abundance. Previously we showed that 300 μl abundance hotspots, coldspots and background regions were distinct at all taxonomic levels. Here we build on these results by showing taxonomic micropatches within these 300 μl microscale hotspots, coldspots and background regions at the 1 μl scale. This heterogeneity among 1 μl subsamples was driven by heightened abundance of specific genera. The micropatches were most pronounced within hotspots. Micropatches were dominated by Pseudomonas, Bacteroides, Parasporobacterium and Lachnospiraceae incertae sedis, with Pseudomonas and Bacteroides being responsible for a shift in the most dominant genera in individual hotspot subsamples, representing up to 80.6% and 47.3% average abundance, respectively. The presence of these micropatches implies the ability these groups have to create, establish themselves in, or exploit heterogeneous microenvironments. These genera are often particle-associated, from which we infer that these micropatches are evidence for sub-millimetre aggregates and the aquatic polymer matrix. These findings support the emerging paradigm that the microscale distributions of planktonic microbes are numerically and taxonomically heterogeneous at scales of millimetres and less. We show that microscale microbial hotspots have internal structure within which specific local nutrient exchanges and cellular interactions might occur.

Ecosystem characteristics and processes facilitating persistent macrobenthic biomass hotspots and associated benthivory in the Pacific Arctic

NASA Astrophysics Data System (ADS)

Grebmeier, Jacqueline M.; Bluhm, Bodil A.; Cooper, Lee W.; Danielson, Seth L.; Arrigo, Kevin R.; Blanchard, Arny L.; Clarke, Janet T.; Day, Robert H.; Frey, Karen E.; Gradinger, Rolf R.; Kędra, Monika; Konar, Brenda; Kuletz, Kathy J.; Lee, Sang H.; Lovvorn, James R.; Norcross, Brenda L.; Okkonen, Stephen R.

2015-08-01

The northern Bering and Chukchi Seas are areas in the Pacific Arctic characterized by high northward advection of Pacific Ocean water, with seasonal variability in sea ice cover, water mass characteristics, and benthic processes. In this review, we evaluate the biological and environmental factors that support communities of benthic prey on the continental shelves, with a focus on four macrofaunal biomass "hotspots." For the purpose of this study, we define hotspots as macrofaunal benthic communities with high biomass that support a corresponding ecological guild of benthivorous seabird and marine mammal populations. These four benthic hotspots are regions within the influence of the St. Lawrence Island Polynya (SLIP), the Chirikov Basin between St. Lawrence Island and Bering Strait (Chirikov), north of Bering Strait in the southeast Chukchi Sea (SECS), and in the northeast Chukchi Sea (NECS). Detailed benthic macrofaunal sampling indicates that these hotspot regions have been persistent over four decades of sampling due to annual reoccurrence of seasonally consistent, moderate-to-high water column production with significant export of carbon to the underlying sediments. We also evaluate the usage of the four benthic hotspot regions by benthic prey consumers to illuminate predator-prey connectivity. In the SLIP hotspot, spectacled eiders and walruses are important winter consumers of infaunal bivalves and polychaetes, along with epibenthic gastropods and crabs. In the Chirikov hotspot, gray whales have historically been the largest summer consumers of benthic macrofauna, primarily feeding on ampeliscid amphipods in the summer, but they are also foraging further northward in the SECS and NECS hotspots. Areas of concentrated walrus foraging occur in the SLIP hotspot in winter and early spring, the NECS hotspot in summer, and the SECS hotspot in fall. Bottom up forcing by hydrography and food supply to the benthos influences persistence and composition of benthic prey

Hopping hotspots: global shifts in marine biodiversity.

PubMed

Renema, W; Bellwood, D R; Braga, J C; Bromfield, K; Hall, R; Johnson, K G; Lunt, P; Meyer, C P; McMonagle, L B; Morley, R J; O'Dea, A; Todd, J A; Wesselingh, F P; Wilson, M E J; Pandolfi, J M

2008-08-01

Hotspots of high species diversity are a prominent feature of modern global biodiversity patterns. Fossil and molecular evidence is starting to reveal the history of these hotspots. There have been at least three marine biodiversity hotspots during the past 50 million years. They have moved across almost half the globe, with their timing and locations coinciding with major tectonic events. The birth and death of successive hotspots highlights the link between environmental change and biodiversity patterns. The antiquity of the taxa in the modern Indo-Australian Archipelago hotspot emphasizes the role of pre-Pleistocene events in shaping modern diversity patterns.

Microbial hotspots and hot moments in soil

NASA Astrophysics Data System (ADS)

Kuzyakov, Yakov; Blagodatskaya, Evgenia

2015-04-01

Soils are the most heterogeneous parts of the biosphere, with an extremely high differentiation of properties and processes within nano- to macroscales. The spatial and temporal heterogeneity of input of labile organics by plants creates microbial hotspots over short periods of time - the hot moments. We define microbial hotspots as small soil volumes with much faster process rates and much more intensive interactions compared to the average soil conditions. Such hotspots are found in the rhizosphere, detritusphere, biopores (including drilosphere) and on aggregate surfaces, but hotspots are frequently of mixed origin. Hot moments are short-term events or sequences of events inducing accelerated process rates as compared to the averaged rates. Thus, hotspots and hot moments are defined by dynamic characteristics, i.e. by process rates. For this hotspot concept we extensively reviewed and examined the localization and size of hotspots, spatial distribution and visualization approaches, transport of labile C to and from hotspots, lifetime and process intensities, with a special focus on process rates and microbial activities. The fraction of active microorganisms in hotspots is 2-20 times higher than in the bulk soil, and their specific activities (i.e. respiration, microbial growth, mineralization potential, enzyme activities, RNA/DNA ratio) may also be much higher. The duration of hot moments in the rhizosphere is limited and is controlled by the length of the input of labile organics. It can last a few hours up to a few days. In the detritusphere, however, the duration of hot moments is regulated by the output - by decomposition rates of litter - and lasts for weeks and months. Hot moments induce succession in microbial communities and intense intra- and interspecific competition affecting C use efficiency, microbial growth and turnover. The faster turnover and lower C use efficiency in hotspots counterbalances the high C inputs, leading to the absence of strong

Crustal magmatism and lithospheric geothermal state of western North America and their implications for a magnetic mantle

NASA Astrophysics Data System (ADS)

Wang, Jian; Li, Chun-Feng

2015-01-01

The western North American lithosphere experienced extensive magmatism and large-scale crustal deformation due to the interactions between the Farallon and North American plates. To further understand such subduction-related dynamic processes, we characterize crustal structure, magmatism and lithospheric thermal state of western North America based on various data processing and interpretation of gravimetric, magnetic and surface heat flow data. A fractal exponent of 2.5 for the 3D magnetization model is used in the Curie-point depth inversion. Curie depths are mostly small to the north of the Yellowstone-Snake River Plain hotspot track, including the Steens Mountain and McDermitt caldera that are the incipient eruption locations of the Columbia River Basalts and Yellowstone hotspot track. To the south of the Yellowstone hotspot track, larger Curie depths are found in the Great Basin. The distinct Curie depths across the Yellowstone-Snake River Plain hotspot track can be attributed to subduction-related magmatism induced by edge flow around fractured slabs. Curie depths confirm that the Great Valley ophiolite is underlain by the Sierra Nevada batholith, which can extend further west to the California Coast Range. The Curie depths, thermal lithospheric thickness and surface heat flow together define the western edge of the North American craton near the Roberts Mountains Thrust (RMT). To the east of the RMT, large Curie depths, large thermal lithospheric thickness, and low thermal gradient are found. From the differences between Curie-point and Moho depth, we argue that the uppermost mantle in the oceanic region is serpentinized. The low temperature gradients beneath the eastern Great Basin, Montana and Wyoming permit magnetic uppermost mantle, either by serpentinization/metasomatism or in-situ magnetization, which can contribute to long-wavelength and low-amplitude magnetic anomalies and thereby large Curie-point depths.

Melt Compositional Diversities in Early Ignimbrite from the 2.08 Ma Huckleberry Ridge Eruption, Yellowstone

NASA Astrophysics Data System (ADS)

Swallow, E. J.; Wilson, C. J. N.; Myers, M.; Collins, K. S.

2016-12-01

Detailed, stratigraphically-constrained geochemical analyses can shed light on the nature of magma systems and mechanisms behind the initiation and escalation of large caldera-forming eruptions1,2. The 2.08 Ma, ˜2,500 km3 Huckleberry Ridge Tuff is the first of three caldera-forming eruptions in the Yellowstone area3, and consists of a widespread initial fall deposit3,4 followed by three ignimbrite members3: A, B and C. Myers et al.2 demonstrated the episodic and multi-vent initiation of the HRT event during eruption of the initial fall deposits, with sequential tapping of three discrete melt bodies, the last of which becomes dominant within the later fall deposits. Here, we build on their dataset to consider glass compositions in the earliest-erupted parts of the overlying ignimbrite (member A). Trace element analyses of ignimbrite shards reveals clustering of compositions and signifies a continuation of the tapping of multiple melt domains. Principal component and cluster analysis indicate at least seven clusters, separated out by crystal fractionation processes. These early flows tapped a range of melts (paralleled by whole-rock magma compositions), from highly evolved (as in the fall deposits) to hotter, less evolved material not represented in the fall deposits. Variations are greatest in Ba (10-900 ppm), Rb/Sr ratios (10-210) and degrees of LREE depletion. However there is an absence of geographical variation, with locations north and south of the subsequent caldera, and in proximal and distal regions, exhibiting similar ranges of glass composition from inferred contemporaneous flow deposition. These observations suggest complexities in the early stages of the tapping of a heterogeneous magma chamber (comprising multiple melt/magma domains), possibly accompanying the onset of caldera collapse. We also consider that external controls, such as rifting, were at least initially important as an eruption trigger2 but understanding of the mechanisms controlling the

Flood estimates for ungaged streams in Glacier and Yellowstone National Parks, Montana

USGS Publications Warehouse

Omang, R.J.; Parrett, Charles; Hull, J.A.

1983-01-01

Estimates of 100-year discharges were made at 59 sites in Glacier National Park and 21 sites in Yellowstone National Park to assist the National Park Services in quantifying stream inflow and outflow in the Parks. The estimates were made using regression equations previously developed for Montana. The resulting 100-year discharges are listed in tables; the discharges ranged from 260 to 53,200 cu ft/s in Glacier National Park and from 110 to 27,900 cu ft/s in Yellowstone National Park. (USGS)

Lower Mantle S-wave Velocity Model under the Western United States

NASA Astrophysics Data System (ADS)

Nelson, P.; Grand, S. P.

2016-12-01

Deep mantle plumes created by thermal instabilities at the core-mantle boundary has been an explanation for intraplate volcanism since the 1970's. Recently, broad slow velocity conduits in the lower mantle underneath some hotspots have been observed (French and Romanowicz, 2015), however the direct detection of a classical thin mantle plume using seismic tomography has remained elusive. Herein, we present a seismic tomography technique designed to image a deep mantle plume under the Yellowstone Hotspot located in the western United States utilizing SKS and SKKS waves in conjunction with finite frequency tomography. Synthetic resolution tests show the technique can resolve a 235 km diameter lower mantle plume with a 1.5% Gaussian velocity perturbation even if a realistic amount of random noise is added to the data. The Yellowstone Hotspot presents a unique opportunity to image a thin plume because it is the only hotspot with a purported deep origin that has a large enough aperture and density of seismometers to accurately sample the lower mantle at the length scales required to image a plume. Previous regional tomography studies largely based on S wave data have imaged a cylindrically shaped slow anomaly extending down to 900km under the hotspot, however they could not resolve it any deeper (Schmandt et al., 2010; Obrebski et al., 2010).To test if the anomaly extends deeper, we measured and inverted over 40,000 SKS and SKKS waves' travel times in two frequency bands recorded at 2400+ stations deployed during 2006-2012. Our preliminary model shows narrow slow velocity anomalies in the lower mantle with no fast anomalies. The slow anomalies are offset from the Yellowstone hotspot and may be diapirs rising from the base of the mantle.

Cosmogenic exposure-age chronologies of Pinedale and Bull Lake glaciations in greater Yellowstone and the Teton Range, USA

USGS Publications Warehouse

Licciardi, J.M.; Pierce, K.L.

2008-01-01

We have obtained 69 new cosmogenic 10Be surface exposure ages from boulders on moraines deposited by glaciers of the greater Yellowstone glacial system and Teton Range during the middle and late Pleistocene. These new data, combined with 43 previously obtained 3He and 10Be ages from deposits of the northern Yellowstone outlet glacier, establish a high-resolution chronology for the Yellowstone-Teton mountain glacier complexes. Boulders deposited at the southern limit of the penultimate ice advance of the Yellowstone glacial system yield a mean age of 136??13 10Be ka and oldest ages of ???151-157 10Be ka. These ages support a correlation with the Bull Lake of West Yellowstone, with the type Bull Lake of the Wind River Range, and with Marine Isotope Stage (MIS) 6. End moraines marking the maximum Pinedale positions of outlet glaciers around the periphery of the Yellowstone glacial system range in age from 18.8??0.9 to 16.5??1.4 10Be ka, and possibly as young as 14.6??0.7 10Be ka, suggesting differences in response times of the various ice-cap source regions. Moreover, all dated Pinedale terminal moraines in the greater Yellowstone glacial system post-date the Pinedale maximum in the Wind River Range by ???4-6 kyr, indicating a significant phase relationship between glacial maxima in these adjacent ranges. Boulders on the outermost set and an inner set of Pinedale end moraines enclosing Jenny Lake on the eastern Teton front yield mean ages of 14.6??0.7 and 13.5??1.1 10Be ka, respectively. The outer Jenny Lake moraines are partially buried by outwash from ice on the Yellowstone Plateau, hence their age indicates a major standstill of an expanded valley glacier in the Teton Range prior to the Younger Dryas, followed closely by deglaciation of the Yellowstone Plateau. These new glacial chronologies are indicative of spatially variable regional climate forcing and temporally complex patterns of glacier responses in this region of the Rocky Mountains during the Pleistocene

Travel Times, Streamflow Velocities, and Dispersion Rates in the Yellowstone River, Montana

USGS Publications Warehouse

McCarthy, Peter M.

2009-01-01

The Yellowstone River is a vital natural resource to the residents of southeastern Montana and is a primary source of water for irrigation and recreation and the primary source of municipal water for several cities. The Yellowstone River valley is the primary east-west transportation corridor through southern Montana. This complex of infrastructure makes the Yellowstone River especially vulnerable to accidental spills from various sources such as tanker cars and trucks. In 2008, the U.S. Geological Survey (USGS), in cooperation with the Montana Department of Environmental Quality, initiated a dye-tracer study to determine instream travel times, streamflow velocities, and dispersion rates for the Yellowstone River from Lockwood to Glendive, Montana. The purpose of this report is to describe the results of this study and summarize data collected at each of the measurement sites between Lockwood and Glendive. This report also compares the results of this study to estimated travel times from a transport model developed by the USGS for a previous study. For this study, Rhodamine WT dye was injected at four locations in late September and early October 2008 during reasonably steady streamflow conditions. Streamflows ranged from 3,490 to 3,770 cubic feet per second upstream from the confluence of the Bighorn River and ranged from 6,520 to 7,570 cubic feet per second downstream from the confluence of the Bighorn River. Mean velocities were calculated for each subreach between measurement sites for the leading edge, peak concentration, centroid, and trailing edge at 10 percent of the peak concentration. Calculated velocities for the centroid of the dye plume for subreaches that were completely laterally mixed ranged from 1.83 to 3.18 ft/s within the study reach from Lockwood Bridge to Glendive Bridge. The mean of the completely mixed centroid velocity for the entire study reach, excluding the subreach between Forsyth Bridge and Cartersville Dam, was 2.80 ft/s. Longitudinal

Volatile emissions and gas geochemistry of Hot Spring Basin, Yellowstone National Park, USA

USGS Publications Warehouse

Werner, C.; Hurwitz, S.; Evans, William C.; Lowenstern, J. B.; Bergfeld, D.; Heasler, H.; Jaworowski, C.; Hunt, A.

2008-01-01

We characterize and quantify volatile emissions at Hot Spring Basin (HSB), a large acid-sulfate region that lies just outside the northeastern edge of the 640??ka Yellowstone Caldera. Relative to other thermal areas in Yellowstone, HSB gases are rich in He and H2, and mildly enriched in CH4 and H2S. Gas compositions are consistent with boiling directly off a deep geothermal liquid at depth as it migrates toward the surface. This fluid, and the gases evolved from it, carries geochemical signatures of magmatic volatiles and water-rock reactions with multiple crustal sources, including limestones or quartz-rich sediments with low K/U (or 40*Ar/4*He). Variations in gas chemistry across the region reflect reservoir heterogeneity and variable degrees of boiling. Gas-geothermometer temperatures approach 300????C and suggest that the reservoir feeding HSB is one of the hottest at Yellowstone. Diffuse CO2 flux in the western basin of HSB, as measured by accumulation-chamber methods, is similar in magnitude to other acid-sulfate areas of Yellowstone and is well correlated to shallow soil temperatures. The extrapolation of diffuse CO2 fluxes across all the thermal/altered area suggests that 410 ?? 140??t d- 1 CO2 are emitted at HSB (vent emissions not included). Diffuse fluxes of H2S were measured in Yellowstone for the first time and likely exceed 2.4??t d- 1 at HSB. Comparing estimates of the total estimated diffuse H2S emission to the amount of sulfur as SO42- in streams indicates ~ 50% of the original H2S in the gas emission is lost into shallow groundwater, precipitated as native sulfur, or vented through fumaroles. We estimate the heat output of HSB as ~ 140-370??MW using CO2 as a tracer for steam condensate, but not including the contribution from fumaroles and hydrothermal vents. Overall, the diffuse heat and volatile fluxes of HSB are as great as some active volcanoes, but they are a small fraction (1-3% for CO2, 2-8% for heat) of that estimated for the entire

The Changing Nature of the Hawaiian Hotspot in the Late Cretaceous-Early Tertiary: Evidence From Helium Isotopes and Melt Inclusion Compositions

NASA Astrophysics Data System (ADS)

Keller, R.; Graham, D.; Duncan, R.; Regelous, M.

2002-12-01

Ocean Drilling Program Leg 197 recovered basaltic basement from three of the Late Cretaceous-Paleogene Emperor seamounts: Detroit (Sites 1203 and 1204), Nintoku (Site 1205), and Koko (Site 1206) seamounts. The depths of penetration into basement achieved by this drilling (140-450 m), the range of rock types recovered (hawaiites, alkalic basalts, and tholeiitic basalts), and the age range (48-76 Ma) makes this one of the most comprehensive collections of the volcanic products of the Hawaiian hotspot available, and opens up new opportunities to study the temporal evolution of the Hawaiian hotspot during the Late Cretaceous and early Tertiary. Previous studies of the chemical evolution of the Hawaiian hotspot (Lanphere et al., 1980; Keller et al., 2000) found significant temporal variations. For example, Sr isotopic ratios of the tholeiitic basalts remain fairly constant along the Hawaiian Islands/Ridge between Kilauea volcano on Hawaii and the Hawaiian-Emperor bend, but then decrease steadily northward along the Emperor seamounts. Trace element compositions (especially the rare earth element patterns) also show limited variations along the Hawaiian Islands/Ridge, but change toward more depleted values northward along the Emperor seamounts. The trend to more MORB-like compositions back in time was attributed to a decrease in distance between the hotspot and the nearest spreading center, although a more comprehensive study suggests that variations in lithospheric thickness also caused changes in the composition of the plume melts (Regelous et al., 2002). We will complement these previous studies and the ongoing work of the other Leg 197 scientists by studying two aspects of the Emperor seamount basalts: helium isotopes and melt inclusion compositions. We will measure the helium isotopic ratios of selected olivine separates from three of the Leg 197 drill sites and from DSDP Site 433 on Suiko seamount (65 Ma) to determine if the composition of the Hawaiian "plume signal

Transmission of infectious diseases en route to habitat hotspots.

PubMed

Benavides, Julio; Walsh, Peter D; Meyers, Lauren Ancel; Raymond, Michel; Caillaud, Damien

2012-01-01

The spread of infectious diseases in wildlife populations is influenced by patterns of between-host contacts. Habitat "hotspots"--places attracting a large numbers of individuals or social groups--can significantly alter contact patterns and, hence, disease propagation. Research on the importance of habitat hotspots in wildlife epidemiology has primarily focused on how inter-individual contacts occurring at the hotspot itself increase disease transmission. However, in territorial animals, epidemiologically important contacts may primarily occur as animals cross through territories of conspecifics en route to habitat hotspots. So far, the phenomenon has received little attention. Here, we investigate the importance of these contacts in the case where infectious individuals keep visiting the hotspots and in the case where these individuals are not able to travel to the hotspot any more. We developed a simulation epidemiological model to investigate both cases in a scenario when transmission at the hotspot does not occur. We find that (i) hotspots still exacerbate epidemics, (ii) when infectious individuals do not travel to the hotspot, the most vulnerable individuals are those residing at intermediate distances from the hotspot rather than nearby, and (iii) the epidemiological vulnerability of a population is the highest when the number of hotspots is intermediate. By altering animal movements in their vicinity, habitat hotspots can thus strongly increase the spread of infectious diseases, even when disease transmission does not occur at the hotspot itself. Interestingly, when animals only visit the nearest hotspot, creating additional artificial hotspots, rather than reducing their number, may be an efficient disease control measure.

Hotspots, polar wander, Mesozoic convection and the geoid

NASA Astrophysics Data System (ADS)

Anderson, D. L.

1981-11-01

The geoid bears little relation to present tectonic features of the earth other than trenches. The Mesozoic supercontinent of Pangea, however, apparently occupied a central position in the Atlantic-African geoid high. This and the equatorial Pacific geoid high contain most of the world's hotspots. The plateaus and rises in the western Pacific formed in the Pacific geoid high and this may have been the early Mesozoic position of Pacifica, the fragments of which are now the Pacific rim portions of the continents. Geoid highs which are unrelated to present subduction zones may be the former sites of continental aggregations and mantle insulation and, therefore, hotter than normal mantle. The pent-up heat causes rifts and hotspots and results in extensive uplift, magmatism, fragmentation and dispersal of the continents and the subsequent formation of plateaus, aseismic ridges and seamount chains. Convection in the uppermantle would then be due to lateral temperature gradients as well as heating from below and would be intrinsically episodic.

Hotspots, polar wander, Mesozoic convection and the geoid

NASA Technical Reports Server (NTRS)

Anderson, D. L.

1981-01-01

The geoid bears little relation to present tectonic features of the earth other than trenches. The Mesozoic supercontinent of Pangea, however, apparently occupied a central position in the Atlantic-African geoid high. This and the equatorial Pacific geoid high contain most of the world's hotspots. The plateaus and rises in the western Pacific formed in the Pacific geoid high and this may have been the early Mesozoic position of Pacifica, the fragments of which are now the Pacific rim portions of the continents. Geoid highs which are unrelated to present subduction zones may be the former sites of continental aggregations and mantle insulation and, therefore, hotter than normal mantle. The pent-up heat causes rifts and hotspots and results in extensive uplift, magmatism, fragmentation and dispersal of the continents and the subsequent formation of plateaus, aseismic ridges and seamount chains. Convection in the uppermantle would then be due to lateral temperature gradients as well as heating from below and would be intrinsically episodic.

Yellowstone volcano-tectonic microseismic cycles constrain models of migrating volcanic fluids

NASA Astrophysics Data System (ADS)

Massin, F.; Farrell, J.; Smith, R. B.

2011-12-01

The objective of our research is to evaluate the source properties of extensive earthquake swarms in and around the 0.64Myr Yellowstone caldera, Yellowstone National Park, that is also the locus of widespread hydrothermal activity and ground deformation. We use earthquake waveforms data to investigate seismic wave multiplets that occur within discrete earthquake sequences. Waveform cross-correlation coefficients are computed from data acquired at six high quality stations that are merged from data of identical earthquakes into multiplets. Multiplets provide important indicators on the rupture process of the distinct seismogenic structures. Our multiplet database allowed evaluation of the seismic-source chronology from 1992 to 2010. We assess the evolution of micro-earthquake triggering by evaluating the evolution of earthquake rates and magnitudes. Some striking differences appear between two kinds of seismic swarms: 1) swarms with a high rate of repeating earthquakes of more than 200 events per day, and 2) swarms with a low rate of repeating earthquakes (less than 20 events per day). The 2010 Madison Plateau, western caldera, and the 2008-2009 Yellowstone Lake, eastern caldera, earthquake swarms are two examples representing respectively cascading relaxation of a uniform stress, and an example of highly concentrated stress perturbation induced by a migrating material. The repeating earthquake pattern methodology was then used to characterize the composition of the migrating material by modelling the migration time-space pattern with a experimental thermo-physical simulations of solidification of a fluid filled propagating dike. Comparison of our results with independent GPS deformation data suggests a most-likely model of rhyolitic-granitic magma intrusion along a vertical dike outlined by the pattern of earthquakes. The magma-hydrothermal mix was modeled with a temperature of 800°C-900°C and an average volumetric injection flux between 1.5 and 5 m3/s. Our

76 FR 37888 - Yellowstone Valley Railroad, L.L.C.-Discontinuance of Service Exemption-in Dawson and Richland...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... contains false or misleading information, the exemption is void ab initio. Board decisions and notices are... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. AB 991X] Yellowstone Valley Railroad, L.L.C.--Discontinuance of Service Exemption--in Dawson and Richland Counties, Mont. Yellowstone...

Gas and isotope chemistry of thermal features in Yellowstone National Park, Wyoming

USGS Publications Warehouse

Bergfeld, D.; Lowenstern, Jacob B.; Hunt, Andrew G.; Shanks, W.C. Pat; Evans, William

2011-01-01

This report presents 130 gas analyses and 31 related water analyses on samples collected from thermal features at Yellowstone between 2003 and 2009. An overview of previous studies of gas emissions at Yellowstone is also given. The analytical results from the present study include bulk chemistry of gases and waters and isotope values for water and steam (delta18O, dealtaD), carbon dioxide (delta13C only), methane (delta13C only), helium, neon, and argon. We include appendixes containing photos of sample sites, geographic information system (GIS) files including shape and kml formats, and analytical results in spreadsheets. In addition, we provide a lengthy discussion of previous work on gas chemistry at Yellowstone and a general discussion of the implications of our results. We demonstrate that gases collected from different thermal areas often have distinct chemical signatures, and that differences across the thermal areas are not a simple function of surface temperatures or the type of feature. Instead, gas chemistry and isotopic composition are linked to subsurface lithologies and varying contributions from magmatic, crustal, and meteoric sources.

Climatic change and wetland desiccation cause amphibian decline in Yellowstone National Park.

PubMed

McMenamin, Sarah K; Hadly, Elizabeth A; Wright, Christopher K

2008-11-04

Amphibians are a bellwether for environmental degradation, even in natural ecosystems such as Yellowstone National Park in the western United States, where species have been actively protected longer than anywhere else on Earth. We document that recent climatic warming and resultant wetland desiccation are causing severe declines in 4 once-common amphibian species native to Yellowstone. Climate monitoring over 6 decades, remote sensing, and repeated surveys of 49 ponds indicate that decreasing annual precipitation and increasing temperatures during the warmest months of the year have significantly altered the landscape and the local biological communities. Drought is now more common and more severe than at any time in the past century. Compared with 16 years ago, the number of permanently dry ponds in northern Yellowstone has increased 4-fold. Of the ponds that remain, the proportion supporting amphibians has declined significantly, as has the number of species found in each location. Our results indicate that climatic warming already has disrupted one of the best-protected ecosystems on our planet and that current assessments of species' vulnerability do not adequately consider such impacts.

Climatic change and wetland desiccation cause amphibian decline in Yellowstone National Park

PubMed Central

McMenamin, Sarah K.; Hadly, Elizabeth A.; Wright, Christopher K.

2008-01-01

Amphibians are a bellwether for environmental degradation, even in natural ecosystems such as Yellowstone National Park in the western United States, where species have been actively protected longer than anywhere else on Earth. We document that recent climatic warming and resultant wetland desiccation are causing severe declines in 4 once-common amphibian species native to Yellowstone. Climate monitoring over 6 decades, remote sensing, and repeated surveys of 49 ponds indicate that decreasing annual precipitation and increasing temperatures during the warmest months of the year have significantly altered the landscape and the local biological communities. Drought is now more common and more severe than at any time in the past century. Compared with 16 years ago, the number of permanently dry ponds in northern Yellowstone has increased 4-fold. Of the ponds that remain, the proportion supporting amphibians has declined significantly, as has the number of species found in each location. Our results indicate that climatic warming already has disrupted one of the best-protected ecosystems on our planet and that current assessments of species' vulnerability do not adequately consider such impacts. PMID:18955700

Transmission of Brucellosis from Elk to Cattle and Bison, Greater Yellowstone Area, USA, 2002–2012

PubMed Central

Nol, Pauline; Quance, Christine; Gertonson, Arnold; Belfrage, John; Harris, Lauren; Straka, Kelly; Robbe-Austerman, Suelee

2013-01-01

Bovine brucellosis has been nearly eliminated from livestock in the United States. Bison and elk in the Greater Yellowstone Area remain reservoirs for the disease. During 1990–2002, no known cases occurred in Greater Yellowstone Area livestock. Since then, 17 transmission events from wildlife to livestock have been investigated. PMID:24274092

Yellowstone wolves and the forces that structure natural systems.

PubMed

Dobson, Andy P

2014-12-01

Since their introduction in 1995 and 1996, wolves have had effects on Yellowstone that ripple across the entire structure of the food web that defines biodiversity in the Northern Rockies ecosystem. Ecological interpretations of the wolves have generated a significant amount of debate about the relative strength of top-down versus bottom-up forces in determining herbivore and vegetation abundance in Yellowstone. Debates such as this are central to the resolution of broader debates about the role of natural enemies and climate as forces that structure food webs and modify ecosystem function. Ecologists need to significantly raise the profile of these discussions; understanding the forces that structure food webs and determine species abundance and the supply of ecosystem services is one of the central scientific questions for this century; its complexity will require new minds, new mathematics, and significant, consistent funding.

Yellowstone Wolves and the Forces That Structure Natural Systems

PubMed Central

Dobson, Andy P.

2014-01-01

Since their introduction in 1995 and 1996, wolves have had effects on Yellowstone that ripple across the entire structure of the food web that defines biodiversity in the Northern Rockies ecosystem. Ecological interpretations of the wolves have generated a significant amount of debate about the relative strength of top-down versus bottom-up forces in determining herbivore and vegetation abundance in Yellowstone. Debates such as this are central to the resolution of broader debates about the role of natural enemies and climate as forces that structure food webs and modify ecosystem function. Ecologists need to significantly raise the profile of these discussions; understanding the forces that structure food webs and determine species abundance and the supply of ecosystem services is one of the central scientific questions for this century; its complexity will require new minds, new mathematics, and significant, consistent funding. PMID:25535737

Hot-spot qualification testing of concentrator modules

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.; Sugimura, R. S.; Ross, R. G., Jr.

1987-01-01

Results of a study to determine the hot-spot susceptibility of concentrator cells, to provide a hot-spot qualification test for concentrator modules, and to provide guidelines for reducing hot-spot susceptibility are presented. Hot-spot heating occurs in a photovoltaic module when the short-circuit current of a cell is lower than the string operating current, forcing the cell into reverse bias with a concurrent power dissipation. Although the basis for the concentrator-module hot-spot qualification test is the test developed for flat-plate modules, issues such as providing cell illumination introduce additional complexities into the testing procedure. The results indicate that the same general guidelines apply to protecting concentrator modules from hot-spot stressing as apply to flat-plate modules, and recommendations are made on the number of bypass diodes required per given number of series cells per module or source circuit. A method for determining the cell temperature in the laboratory or in the field is discussed.

Transmission of Infectious Diseases En Route to Habitat Hotspots

PubMed Central

Benavides, Julio; Walsh, Peter D.; Meyers, Lauren Ancel; Raymond, Michel; Caillaud, Damien

2012-01-01

Background The spread of infectious diseases in wildlife populations is influenced by patterns of between-host contacts. Habitat “hotspots” - places attracting a large numbers of individuals or social groups - can significantly alter contact patterns and, hence, disease propagation. Research on the importance of habitat hotspots in wildlife epidemiology has primarily focused on how inter-individual contacts occurring at the hotspot itself increase disease transmission. However, in territorial animals, epidemiologically important contacts may primarily occur as animals cross through territories of conspecifics en route to habitat hotspots. So far, the phenomenon has received little attention. Here, we investigate the importance of these contacts in the case where infectious individuals keep visiting the hotspots and in the case where these individuals are not able to travel to the hotspot any more. Methodology and Principal Findings We developed a simulation epidemiological model to investigate both cases in a scenario when transmission at the hotspot does not occur. We find that (i) hotspots still exacerbate epidemics, (ii) when infectious individuals do not travel to the hotspot, the most vulnerable individuals are those residing at intermediate distances from the hotspot rather than nearby, and (iii) the epidemiological vulnerability of a population is the highest when the number of hotspots is intermediate. Conclusions and Significance By altering animal movements in their vicinity, habitat hotspots can thus strongly increase the spread of infectious diseases, even when disease transmission does not occur at the hotspot itself. Interestingly, when animals only visit the nearest hotspot, creating additional artificial hotspots, rather than reducing their number, may be an efficient disease control measure. PMID:22363606

A Western Pacific Hotspot?

NASA Astrophysics Data System (ADS)

MacPherson, C. G.; Hall, R.

2003-04-01

The petrology of volcanic rocks from the St. Andrew Strait and helium isotope ratios of backarc lavas from the Manus Basin have been used to propose the existence of an active hotspot beneath the eastern Bismarck Sea (Johnson et al., 1978; Macpherson et al., 1998). The past influence of this hotspot can be assessed by mapping its present location onto a plate tectonic reconstruction of the western Pacific (Macpherson and Hall, 2001). During the Middle Eocene the nascent Izu-Bonin-Mariana (IBM) arc lay above the hotspot. The volume of magma emplaced at the IBM arc at that time substantially exceeds the average magma production rate for mature island arcs. Furthermore, the ultramafic (boninitic) character of much of this magmatism requires elevated temperatures. The geochemistry of contemporaneous magmatism in the backarc resembles ocean island basalts and much of the backarc region experienced significant uplift at that time. All of these features can be explained by the influx of hot, buoyant, chemically distinct mantle beneath the IBM and its hinterland. The lithosphere lying above the hotspot during the later Eocene was subsequently subducted. During the Oligo-Miocene the hotspot was traversed by parts of the Caroline Plate where the Euripik Rise is found. This is an aseismic rise that possesses the geophysical characteristics of thickened oceanic crust formed by excess, basaltic magmatism and is the type of structure that would result from the passage of relatively young oceanic lithosphere over a mantle hotspot. Plate reconstruction for the western Pacific predicts a hotspot trail that is consistent with the Middle Eocene and Oligo-Miocene geology of the IBM and Caroline Plates, respectively (Macpherson and Hall, 2001). Parts of the trail have been disrupted by subsequent sea-floor spreading or lost through subduction but the remaining vestiges are consistent with the action of a thermal anomaly throughout much of the Cenozoic. More speculatively, buoyancy

NIMS: Hotspots on Io During G2

NASA Image and Video Library

1998-03-26

The Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft imaged Io at high spectral resolution at a range of 439,000 km (275,000 miles) during the G2 encounter on 7 September 1996. This image shows (on the right) Io as seen in the infrared by NIMS. The image on the left shows the same view from Voyager in 1979. This NIMS image can be compared to the NIMS images from the G1 orbit (June 1996) to monitor changes on Io. The NIMS image is at 4.9 microns, showing thermal emissions from the hotspots. The brightness of the pixels is a function of size and temperature. At least 10 hotspots have been identified and can be matched with surface features. An accurate determination of the position of the hotspot in the vicinity of Shamash Patera is pending. Hotspots are seen in the vicinity of Prometheus, Volund and Marduk, all sites of volcanic plume activity during the Galileo encounters, and also of active plumes in 1979. Temperatures and areas have been calculated for the hotspots shown. Temperatures range from 828 K (1031 F) to 210 K (- 81.4 F). The lowest temperature is significantly higher than the Io background (non-hotspot) surface temperature of about 100 K (-279 F). Hotspot areas range from 6.5 square km (2.5 sq miles) to 40,000 sq km (15,400 sq miles). The hottest hotspots have smallest areas, and the cooler hotspots have the largest areas. NIMS is continuing to observe Io to monitor volcanic activity throughout the Galileo mission. http://photojournal.jpl.nasa.gov/catalog/PIA00520

Where are the lightning hotspots on Earth?

NASA Astrophysics Data System (ADS)

Albrecht, R. I.; Goodman, S. J.; Buechler, D. E.; Blakeslee, R. J.; Christian, H. J., Jr.

2015-12-01

The first lightning observations from space date from the early 1960s and more than a dozen spacecraft orbiting the Earth have flown instruments that recorded lightning signals from thunderstorms over the past 45 years. In this respect, the Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor (LIS), having just completed its mission (1997-2015), provides the longest and best total (intracloud and cloud-to-ground) lightning data base over the tropics.We present a 16 year (1998-2013) reprocessed data set to create very high resolution (0.1°) TRMM LIS total lightning climatology. This detailed very high resolution climatology is used to identify the Earth's lightning hotspots and other regional features. Earlier studies located the lightning hotspot within the Congo Basin in Africa, but our very high resolution lightning climatology found that the highest lightning flash rate on Earth actually occurs in Venezuela over Lake Maracaibo, with a distinct maximum during the night. The higher resolution dataset clearly shows that similar phenomenon also occurs over other inland lakes with similar conditions, i.e., locally forced convergent flow over a warm lake surface which drives deep nocturnal convection. Although Africa does not have the top lightning hotspot, it comes in a close second and it is the continent with the highest number of lightning hotspots, followed by Asia, South America, North America, and Oceania. We also present climatological maps for local hour and month of lightning maxima, along with a ranking of the highest five hundred lightning maxima, focusing discussion on each continent's 10 highest lightning maxima. Most of the highest continental maxima are located near major mountain ranges, revealing the importance of local topography in thunderstorm development. These results are especially relevant in anticipation of the upcoming availability of continuous total lightning observations from the Geostationary Lightning Mapping (GLM

Streamflow statistics for unregulated and regulated conditions for selected locations on the Yellowstone, Tongue, and Powder Rivers, Montana, 1928-2002

USGS Publications Warehouse

Chase, Katherine J.

2013-01-01

Major floods in 1996 and 1997 on the Yellowstone River in Montana intensified public debate over the effects of human activities on the Yellowstone River. In 1999, the Yellowstone River Conservation District Council was formed to address conservation issues on the river. The Yellowstone River Conservation District Council partnered with the U.S. Army Corps of Engineers to conduct a cumulative-effects study on the main stem of the Yellowstone River. The cumulative-effects study is intended to provide a basis for future management decisions in the watershed. Streamflow statistics, such as flow-frequency and flow-duration data calculated for unregulated and regulated streamflow conditions, are a necessary component of the cumulative effects study. The U.S. Geological Survey, in cooperation with the Yellowstone River Conservation District Council and the U.S. Army Corps of Engineers, calculated streamflow statistics for unregulated and regulated conditions for the Yellowstone, Tongue, and Powder Rivers for the 1928–2002 study period. Unregulated streamflow represents flow conditions that might have occurred during the 1928–2002 study period if there had been no water-resources development in the Yellowstone River Basin. Regulated streamflow represents estimates of flow conditions during the 1928–2002 study period if the level of water-resources development existing in 2002 was in place during the entire study period. Peak-flow frequency estimates for regulated and unregulated streamflow were developed using methods described in Bulletin 17B. High-flow frequency and low-flow frequency data were developed for regulated and unregulated streamflows from the annual series of highest and lowest (respectively) mean flows for specified n-day consecutive periods within the calendar year. Flow-duration data, and monthly and annual streamflow characteristics, also were calculated for the unregulated and regulated streamflows.

Helium isotope, C/3He, and Ba-Nb-Ti signatures in the northern Lau Basin: Distinguishing arc, back-arc, and hotspot affinities

NASA Astrophysics Data System (ADS)

Lupton, John; Rubin, Ken H.; Arculus, Richard; Lilley, Marvin; Butterfield, David; Resing, Joseph; Baker, Edward; Embley, Robert

2015-04-01

The northern Lau Basin hosts a complicated pattern of volcanism, including Tofua Arc volcanoes, several back-arc spreading centers, and individual "rear-arc" volcanoes not associated with these structures. Elevated 3He/4He ratios in lavas of the NW Lau Spreading Center suggest the influence of a mantle plume, possibly from Samoa. We show that lavas from mid-ocean ridges, volcanic arcs, and hotspots occupy distinct, nonoverlapping fields in a 3He/4He versus C/3He plot. Applied to the northern Lau Basin, this approach shows that most of Lau back-arc spreading systems have mid-ocean ridge 3He/4He-C/3He characteristics, except the NW Lau spreading center, which has 3He/4He-C/3He similar to "high 3He" hotspots such as Loihi, Kilauea, and Yellowstone, but with slightly lower C/3He. Niua seamount, on the northern extension of the Tofua Arc, falls squarely in the arc field. All the NE Lau rear-arc volcanoes, including the recently erupting West Mata, also have arc-like 3He/4He-C/3He characteristics. Ba-Nb-Ti contents of the lavas, which are more traditional trace element indicators of mantle source enrichment, depletion, and subduction input, likewise indicate arc and hot spot influences in the lavas of the northern Lau Basin, but in a more ambiguous fashion because of a complex prior history. This verifies that 3He/4He-C/3He systematics are useful for differentiating between mid-ocean ridge, arc, and hotspot affinities in submarine volcanic systems, that all three of these affinities are expressed in the northern Lau Basin, and provides additional support for the Samoan plume influence in the region.

Hotspots and Superswell Beneath Africa Inferred From Surface Wave Anisotropic Tomography.

NASA Astrophysics Data System (ADS)

Sebai, A.; Stutzmann, E.; Montagner, J.

2003-12-01

In order to study the interaction at depth between hotspots and lithosphere we present a new anisotropic S-wave tomographic model of Africa which is derived from Rayleigh and Love wave phase velocity measurements. The strongest negative anomaly corresponds to the Afar plume which is presently the most active area of Africa. This slow anomaly, visible down to the deepest inverted depth (400km), is associated with azimuthal anisotropy that is weak right beneath the Afar and whose direction at further distances is diverging around the plume. This is consistent with active upwelling beneath the Afar. The smaller hotspots of Tibesti, Darfur, Hoggar and Mt Cameroon have appeared in regions that had been weakened by Late Jurassic-Early Cretaceous (145 Ma) rifting of West and Central Africa. They are associated with slow velocities down to about 200km. The smaller amplitude of these anomalies with respect to the Afar area and their limited depth extent may indicate that these hotspots have their origin in the uppermost boundary layer between asthenosphere and lithosphere. Nevertheless, there may be a complex relationship at depths shallower than 150km between these hotspots and the Afar. The superswell, located in the southern part of Africa is characterized by a broad area of positive velocity anomaly visible down to 300km depth. The base of Kalahari craton ( ˜ 280 km) is evidently characterized by an increase of azimuthal anisotropy. The direction of azimuthal axis is roughly North-South that rotates at the longitude of the Eastern rift to move around the Afar. This may suggest a feeding of Victoria and Afar hotspots from the deep South African superplume.

Geochemistry of High Temperature Vent Fluids in Yellowstone Lake: Dissolved Carbon and Sulfur Concentrations and Isotopic Data

NASA Astrophysics Data System (ADS)

Cino, C.; Seyfried, W. E., Jr.; Tan, C.; Fu, Q.

2017-12-01

Yellowstone National Park is a dynamic environment home to an array of geysers, hot springs, and hydrothermal vents fueled by the underlying continental magmatic intrusion. Yellowstone Lake vent fluids accounts for approximately 10% of the total geothermal flux for all of Yellowstone National Park. Though studying this remote hydrothermal system poses severe challenges, it provides an excellent natural laboratory to research hydrothermal fluids that undergo higher pressure and temperature conditions in an environment largely shielded from atmospheric oxygen. The location of these vents also provides chemistry that is characteristic of fluids deeper in the Yellowstone hydrothermal system. In August 2016, hydrothermal fluids were collected from the Stevenson Island vents in collaboration with the Hydrothermal Dynamics of Yellowstone Lake (HD-YLAKE) project using novel sampling techniques and monitoring instrumentation. The newly built ROV Yogi was deployed to reach the vents in-situ with temperatures in excess of 151oC at 100-120 m depth, equipped with a 12-cylinder isobaric sampler to collect the hydrothermal fluids. Results from geochemical analyses indicate the fluids are rich in gases such as CO2, CH4, and H2S, with sample concentrations of approximately 12 mM, 161 μm, and 2.1 mM respectively. However, lake water mixing with the hydrothermal endmember fluid likely diluted these concentrations in the collected samples. Isotopic analyses indicate CO2 has a δ13C of -6 indicating magmatic origins, however the CH4 resulted in a δ13C of -65 which is in the biological range. This biogenic signature is likely due to the pyrolysis of immature organic matter in the lake bottom sediment, since the high temperatures measured for the fluids would not allow the presence of methanogens. H2S concentrations have not been previously measured for the hydrothermal fluids in Yellowstone Lake, and our vent fluid samples indicate significantly higher H2S concentrations than reported

Evaluating Temporal Consistency in Marine Biodiversity Hotspots.

PubMed

Piacenza, Susan E; Thurman, Lindsey L; Barner, Allison K; Benkwitt, Cassandra E; Boersma, Kate S; Cerny-Chipman, Elizabeth B; Ingeman, Kurt E; Kindinger, Tye L; Lindsley, Amy J; Nelson, Jake; Reimer, Jessica N; Rowe, Jennifer C; Shen, Chenchen; Thompson, Kevin A; Heppell, Selina S

2015-01-01

With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap, we present an approach to evaluate the temporal consistency of biodiversity hotspots in large marine ecosystems. Using a large scale, public monitoring dataset collected over an eight year period off the US Pacific Coast, we developed a methodological approach for avoiding biases associated with hotspot delineation. We aggregated benthic fish species data from research trawls and calculated mean hotspot thresholds for fish species richness and Shannon's diversity indices over the eight year dataset. We used a spatial frequency distribution method to assign hotspot designations to the grid cells annually. We found no areas containing consistently high biodiversity through the entire study period based on the mean thresholds, and no grid cell was designated as a hotspot for greater than 50% of the time-series. To test if our approach was sensitive to sampling effort and the geographic extent of the survey, we followed a similar routine for the northern region of the survey area. Our finding of low consistency in benthic fish biodiversity hotspots over time was upheld, regardless of biodiversity metric used, whether thresholds were calculated per year or across all years, or the spatial extent for which we calculated thresholds and identified hotspots. Our results suggest that static measures of benthic fish biodiversity off the US West Coast are insufficient for identification of hotspots and that long-term data are required to appropriately identify patterns of high temporal variability in biodiversity for these highly mobile taxa. Given that ecological communities are responding to a changing climate and other

Evaluating Temporal Consistency in Marine Biodiversity Hotspots

PubMed Central

Barner, Allison K.; Benkwitt, Cassandra E.; Boersma, Kate S.; Cerny-Chipman, Elizabeth B.; Ingeman, Kurt E.; Kindinger, Tye L.; Lindsley, Amy J.; Nelson, Jake; Reimer, Jessica N.; Rowe, Jennifer C.; Shen, Chenchen; Thompson, Kevin A.; Heppell, Selina S.

2015-01-01

With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap, we present an approach to evaluate the temporal consistency of biodiversity hotspots in large marine ecosystems. Using a large scale, public monitoring dataset collected over an eight year period off the US Pacific Coast, we developed a methodological approach for avoiding biases associated with hotspot delineation. We aggregated benthic fish species data from research trawls and calculated mean hotspot thresholds for fish species richness and Shannon’s diversity indices over the eight year dataset. We used a spatial frequency distribution method to assign hotspot designations to the grid cells annually. We found no areas containing consistently high biodiversity through the entire study period based on the mean thresholds, and no grid cell was designated as a hotspot for greater than 50% of the time-series. To test if our approach was sensitive to sampling effort and the geographic extent of the survey, we followed a similar routine for the northern region of the survey area. Our finding of low consistency in benthic fish biodiversity hotspots over time was upheld, regardless of biodiversity metric used, whether thresholds were calculated per year or across all years, or the spatial extent for which we calculated thresholds and identified hotspots. Our results suggest that static measures of benthic fish biodiversity off the US West Coast are insufficient for identification of hotspots and that long-term data are required to appropriately identify patterns of high temporal variability in biodiversity for these highly mobile taxa. Given that ecological communities are responding to a changing climate and other

Ultraconfined Plasmonic Hotspots Inside Graphene Nanobubbles.

PubMed

Fei, Z; Foley, J J; Gannett, W; Liu, M K; Dai, S; Ni, G X; Zettl, A; Fogler, M M; Wiederrecht, G P; Gray, S K; Basov, D N

2016-12-14

We report on a nanoinfrared (IR) imaging study of ultraconfined plasmonic hotspots inside graphene nanobubbles formed in graphene/hexagonal boron nitride (hBN) heterostructures. The volume of these plasmonic hotspots is more than one-million-times smaller than what could be achieved by free-space IR photons, and their real-space distributions are controlled by the sizes and shapes of the nanobubbles. Theoretical analysis indicates that the observed plasmonic hotspots are formed due to a significant increase of the local plasmon wavelength in the nanobubble regions. Such an increase is attributed to the high sensitivity of graphene plasmons to its dielectric environment. Our work presents a novel scheme for plasmonic hotspot formation and sheds light on future applications of graphene nanobubbles for plasmon-enhanced IR spectroscopy.

Exterior sound level measurements of snowcoaches at Yellowstone National Park

DOT National Transportation Integrated Search

2010-04-01

Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an important management concern at Yellowstone and Grand Teton National Parks. The John A. Volpe National Transportation Systems Centers Environmental Measurement a...

Application of GIS to predict malaria hotspots based on Anopheles arabiensis habitat suitability in Southern Africa

NASA Astrophysics Data System (ADS)

Gwitira, Isaiah; Murwira, Amon; Zengeya, Fadzai M.; Shekede, Munyaradzi Davis

2018-02-01

Malaria remains a major public health problem and a principal cause of morbidity and mortality in most developing countries. Although malaria still presents health problems, significant successes have been recorded in reducing deaths resulting from the disease. As malaria transmission continues to decline, control interventions will increasingly depend on the ability to define high-risk areas known as malaria hotspots. Therefore, there is urgent need to use geospatial tools such as geographic information system to detect spatial patterns of malaria and delineate disease hot spots for better planning and management. Thus, accurate mapping and prediction of seasonality of malaria hotspots is an important step towards developing strategies for effective malaria control. In this study, we modelled seasonal malaria hotspots as a function of habitat suitability of Anopheles arabiensis (A. Arabiensis) as a first step towards predicting likely seasonal malaria hotspots that could provide guidance in targeted malaria control. We used Geographical information system (GIS) and spatial statistic methods to identify seasonal hotspots of malaria cases at the country level. In order to achieve this, we first determined the spatial distribution of seasonal malaria hotspots using the Getis Ord Gi* statistic based on confirmed positive malaria cases recorded at health facilities in Zimbabwe over four years (1996-1999). We then used MAXENT technique to model habitat suitability of A. arabiensis from presence data collected from 1990 to 2002 based on bioclimatic variables and altitude. Finally, we used autologistic regression to test the extent to which malaria hotspots can be predicted using A. arabiensis habitat suitability. Our results show that A. arabiensis habitat suitability consistently and significantly (p < 0.05) predicts malaria hotspots from 1996 to 1999. Overall, our results show that malaria hotspots can be predicted using A. arabiensis habitat suitability, suggesting

Genomic features shaping the landscape of meiotic double-strand-break hotspots in maize.

PubMed

He, Yan; Wang, Minghui; Dukowic-Schulze, Stefanie; Zhou, Adele; Tiang, Choon-Lin; Shilo, Shay; Sidhu, Gaganpreet K; Eichten, Steven; Bradbury, Peter; Springer, Nathan M; Buckler, Edward S; Levy, Avraham A; Sun, Qi; Pillardy, Jaroslaw; Kianian, Penny M A; Kianian, Shahryar F; Chen, Changbin; Pawlowski, Wojciech P

2017-11-14

Meiotic recombination is the most important source of genetic variation in higher eukaryotes. It is initiated by formation of double-strand breaks (DSBs) in chromosomal DNA in early meiotic prophase. The DSBs are subsequently repaired, resulting in crossovers (COs) and noncrossovers (NCOs). Recombination events are not distributed evenly along chromosomes but cluster at recombination hotspots. How specific sites become hotspots is poorly understood. Studies in yeast and mammals linked initiation of meiotic recombination to active chromatin features present upstream from genes, such as absence of nucleosomes and presence of trimethylation of lysine 4 in histone H3 (H3K4me3). Core recombination components are conserved among eukaryotes, but it is unclear whether this conservation results in universal characteristics of recombination landscapes shared by a wide range of species. To address this question, we mapped meiotic DSBs in maize, a higher eukaryote with a large genome that is rich in repetitive DNA. We found DSBs in maize to be frequent in all chromosome regions, including sites lacking COs, such as centromeres and pericentromeric regions. Furthermore, most DSBs are formed in repetitive DNA, predominantly Gypsy retrotransposons, and only one-quarter of DSB hotspots are near genes. Genic and nongenic hotspots differ in several characteristics, and only genic DSBs contribute to crossover formation. Maize hotspots overlap regions of low nucleosome occupancy but show only limited association with H3K4me3 sites. Overall, maize DSB hotspots exhibit distribution patterns and characteristics not reported previously in other species. Understanding recombination patterns in maize will shed light on mechanisms affecting dynamics of the plant genome.

Revisiting Hotspots and Mantle Plumes: Some Phenomenology

NASA Astrophysics Data System (ADS)

King, S. D.; White-Gaynor, A. L.

2012-12-01

Sleep (1990) used gravity, topography and heat flow from 37 hotspots to ``constrain the mechanism for swell uplift and to obtain fluxes and excess temperatures of mantle plumes,'' complementing a previous analysis by Davies (1988). We repeat that analysis for the same 37 hotspots using gravity from EGM2008 and topography from ETOPO1 (Amante and Eakins, 2009). EGM2008 is complete to spherical harmonic degree and order 2159, or roughly 20 km spatial resolution (Pavlis et al., 2012). The vertical accuracy of ETOPO1 is on the order of 10 meters. With these new models we hope to improve the uplift and subsidence rates along all 37 hotspot tracks--one of the major limitations the previous work. For example, of the 37 hotspots considered Sleep ranked only 7 with good reliability while 14 were fair and 16 were poor. With this new information we can compare and contrast hotspots with various other groupings of hotspots based on tomographic images of mantle structure (Montelli et al, 2003), primary versus secondary hotspots (Courtillot et al., 2003) or relationship to cratonic boundaries (King, 2008). One encounters some puzzles when attempting to reconcile buoyancy fluxes with other groupings of hotspots and/or observations. For example, Coutillot et al.'s seven primary hotspots include: Afar, Easter, Hawaii, Iceland, Louisville, Réunion, and Tristan. Sleep (1990) categorized the reliability of the buoyancy flux calculated by from Afar, Hawaii, Iceland, and Réunion as good, while Tristan and Easter were fair and Louisville was poor. The calculated buoyancy fluxes from Macdonald and Marqueses (both listed as fair) are twice as large as those from Iceland, Tristan, and Réunion. While we recognize that these observations cannot uniquely constrain the origin of these anomalies, better observations should help test various hypotheses.

Migrations and swimming capabilities of endangered pallid sturgeon (Scaphirhynchus albus) to guide passage designs in the fragmented Yellowstone River

USGS Publications Warehouse

Braaten, P. J.; Elliott, Caroline M.; Rhoten, Jason C.; Fuller, D. B.; McElroy, Brandon J.

2015-01-01

Fragmentation of the Yellowstone River is hypothesized to preclude recruitment of endangered Scaphirhynchus albus (pallid sturgeon) by impeding upstream spawning migrations and access to upstream spawning areas, thereby limiting the length of free-flowing river required for survival of early life stages. Building on this hypothesis, the reach of the Yellowstone River affected by Intake Diversion Dam (IDD) is targeted for modification. Structures including a rock ramp and by-pass channel have been proposed as restoration alternatives to facilitate passage. Limited information on migrations and swimming capabilities of pallid sturgeon is available to guide engineering design specifications for the proposed structures. Migration behavior, pathways (channel routes used during migrations), and swimming capabilities of free-ranging wild adult pallid sturgeon were examined using radiotelemetry, and complemented with hydraulic data obtained along the migration pathways. Migrations of 12–26% of the telemetered pallid sturgeon population persisted to IDD, but upstream passage over the dam was not detected. Observed migration pathways occurred primarily through main channel habitats; however, migrations through side channels up to 3.9 km in length were documented. The majority of pallid sturgeon used depths of 2.2–3.4 m and mean water velocities of 0.89–1.83 m/s while migrating. Results provide inferences on depths, velocities, and habitat heterogeneity of reaches successfully negotiated by pallid sturgeon that may be used to guide designs for structures facilitating passage at IDD. Passage will provide connectivity to potential upstream spawning areas on the Yellowstone River, thereby increasing the likelihood of recruitment for this endangered species.

The genealogy and genetic viability of reintroduced Yellowstone grey wolves.

PubMed

Vonholdt, Bridgett M; Stahler, Daniel R; Smith, Douglas W; Earl, Dent A; Pollinger, John P; Wayne, Robert K

2008-01-01

The recovery of the grey wolf in Yellowstone National Park is an outstanding example of a successful reintroduction. A general question concerning reintroduction is the degree to which genetic variation has been preserved and the specific behavioural mechanisms that enhance the preservation of genetic diversity and reduce inbreeding. We have analysed 200 Yellowstone wolves, including all 31 founders, for variation in 26 microsatellite loci over the 10-year reintroduction period (1995-2004). The population maintained high levels of variation (1995 H(0) = 0.69; 2004 H(0) = 0.73) with low levels of inbreeding (1995 F(IS) = -0.063; 2004 F(IS) = -0.051) and throughout, the population expanded rapidly (N(1995) = 21; N(2004) = 169). Pedigree-based effective population size ratios did not vary appreciably over the duration of population expansion (1995 N(e)/N(g) = 0.29; 2000 N(e)/N(g) = 0.26; 2004 N(e)/N(g) = 0.33). We estimated kinship and found only two of 30 natural breeding pairs showed evidence of being related (average r = -0.026, SE = 0.03). We reconstructed the genealogy of 200 wolves based on genetic and field data and discovered that they avoid inbreeding through a wide variety of behavioural mechanisms including absolute avoidance of breeding with related pack members, male-biased dispersal to packs where they breed with nonrelatives, and female-biased subordinate breeding. We documented a greater diversity of such population assembly patterns in Yellowstone than previously observed in any other natural wolf population. Inbreeding avoidance is nearly absolute despite the high probability of within-pack inbreeding opportunities and extensive interpack kinship ties between adjacent packs. Simulations showed that the Yellowstone population has levels of genetic variation similar to that of a population managed for high variation and low inbreeding, and greater than that expected for random breeding within packs or across the entire breeding pool. Although short

Identifying species threat hotspots from global supply chains.

PubMed

Moran, Daniel; Kanemoto, Keiichiro

2017-01-04

Identifying hotspots of species threat has been a successful approach for setting conservation priorities. One important challenge in conservation is that, in many hotspots, export industries continue to drive overexploitation. Conservation measures must consider not just the point of impact, but also the consumer demand that ultimately drives resource use. To understand which species threat hotspots are driven by which consumers, we have developed a new approach to link a set of biodiversity footprint accounts to the hotspots of threatened species on the IUCN Red List of Threatened Species. The result is a map connecting consumption to spatially explicit hotspots driven by production on a global scale. Locating biodiversity threat hotspots driven by consumption of goods and services can help to connect conservationists, consumers, companies and governments in order to better target conservation actions.

Reproductive development in the sicklefin chub in the Missouri and Lower Yellowstone Rivers

USGS Publications Warehouse

Dieterman, Douglas J.; Roberts, Eric; Braaten, Patrick J.; Galat, David L.

2006-01-01

We describe aspects of sicklefin chub (Macrhybopsis meeki) reproductive development from three study areas encompassing greater than 2,700 km of the Missouri and Lower Yellowstone rivers. The sicklefin chub was collected between late July and early October in 1996 and 1997. A total of 193 sicklefin chub was collected and examined for reproductive characteristics. Twenty-nine sicklefin chub were found to be reproductively mature females. Some sicklefin chub matured at age 2, but most matured at age 3 and all matured by age 4. Females first became mature at 70 to 79 mm total length (TL) in the Upper Missouri River reach in central Montana, 80 to 89 mm TL in the Missouri and Lower Yellowstone rivers in eastern Montana-western North Dakota, and 90 to 99 mm TL in the lower Missouri River in Nebraska, Iowa, Kansas, and Missouri. Gonad mass of gravid females averaged 6.9% of total body mass and ranged from 1.7 to 13.5%. Total number of oocytes per female, ranged from 7 to 1,561. Reproductive development of the sicklefin chub appeared to be group synchronous or synchronous indicating multiple spawnings during a spawning season. This variability in spawning mode required cautious interpretation of gonadosomatic index values and oocyte counts as estimates of total fecundity, because some females might have released a cohort of oocytes prior to their capture.

Microbial micropatches within microbial hotspots

PubMed Central

Smith, Renee J.; Tobe, Shanan S.; Paterson, James S.; Seymour, Justin R.; Oliver, Rod L.; Mitchell, James G.

2018-01-01

The spatial distributions of organism abundance and diversity are often heterogeneous. This includes the sub-centimetre distributions of microbes, which have ‘hotspots’ of high abundance, and ‘coldspots’ of low abundance. Previously we showed that 300 μl abundance hotspots, coldspots and background regions were distinct at all taxonomic levels. Here we build on these results by showing taxonomic micropatches within these 300 μl microscale hotspots, coldspots and background regions at the 1 μl scale. This heterogeneity among 1 μl subsamples was driven by heightened abundance of specific genera. The micropatches were most pronounced within hotspots. Micropatches were dominated by Pseudomonas, Bacteroides, Parasporobacterium and Lachnospiraceae incertae sedis, with Pseudomonas and Bacteroides being responsible for a shift in the most dominant genera in individual hotspot subsamples, representing up to 80.6% and 47.3% average abundance, respectively. The presence of these micropatches implies the ability these groups have to create, establish themselves in, or exploit heterogeneous microenvironments. These genera are often particle-associated, from which we infer that these micropatches are evidence for sub-millimetre aggregates and the aquatic polymer matrix. These findings support the emerging paradigm that the microscale distributions of planktonic microbes are numerically and taxonomically heterogeneous at scales of millimetres and less. We show that microscale microbial hotspots have internal structure within which specific local nutrient exchanges and cellular interactions might occur. PMID:29787564

Building a global hotspot ecology with Triana data

NASA Astrophysics Data System (ADS)

Gerstl, Siegfried A. W.

1999-12-01

Triana is an Earth remote sensing satellite to be located at the distant Langrange Point L-1, the gravity-neutral point between the Earth and the Sun. It will provide continuous fill disk images of the entire sunlit side of the Earth with 8 km pixel resolution. The primary remote sensing instrument on Triana is a calibrated multispectral imager with 10 spectral channels in the UV, VIS, and NIR between 317 and 870 nm (reflected solar radiation). Due to its unique location at the Lagrange L-1 point, in the direct line-of-sight between Earth and Sun, Triana will view the Earth always in and near the solar retro-reflection direction which is also known as the hotspot direction. The canopy hotspot effect has rich information content for vegetation characterization, especially indications of canopy structure and vegetation health and stress situations. Primary vegetation-related data are the hotspot angular width W, and a hotspot factor C that quantifies the magnitude of the hotspot effect. Both quantities are related to the structural parameters of canopy height, foliage size, shape, and leaf area index (LAI). The continuous observations by Triana will allow us to establish time-series of these ecological parameters for all land biomes by longitude, latitude, and wavelength, that form the basis data set for a new global hotspot land vegetation ecology. The hotspot factor C will allow the determination of the enhanced radiant flux reflected from the Earth into space due to the hotspot effect. The hotspot flux enhancement due to the vegetation hotspot effect is estimated to account for about 1% of the entire Earth radiative energy balance.

The lipodystrophic hotspot lamin A p.R482W mutation deregulates the mesodermal inducer T/Brachyury and early vascular differentiation gene networks.

PubMed

Briand, Nolwenn; Guénantin, Anne-Claire; Jeziorowska, Dorota; Shah, Akshay; Mantecon, Matthieu; Capel, Emilie; Garcia, Marie; Oldenburg, Anja; Paulsen, Jonas; Hulot, Jean-Sebastien; Vigouroux, Corinne; Collas, Philippe

2018-04-15

The p.R482W hotspot mutation in A-type nuclear lamins causes familial partial lipodystrophy of Dunnigan-type (FPLD2), a lipodystrophic syndrome complicated by early onset atherosclerosis. Molecular mechanisms underlying endothelial cell dysfunction conferred by the lamin A mutation remain elusive. However, lamin A regulates epigenetic developmental pathways and mutations could perturb these functions. Here, we demonstrate that lamin A R482W elicits endothelial differentiation defects in a developmental model of FPLD2. Genome modeling in fibroblasts from patients with FPLD2 caused by the lamin A R482W mutation reveals repositioning of the mesodermal regulator T/Brachyury locus towards the nuclear center relative to normal fibroblasts, suggesting enhanced activation propensity of the locus in a developmental model of FPLD2. Addressing this issue, we report phenotypic and transcriptional alterations in mesodermal and endothelial differentiation of induced pluripotent stem cells we generated from a patient with R482W-associated FPLD2. Correction of the LMNA mutation ameliorates R482W-associated phenotypes and gene expression. Transcriptomics links endothelial differentiation defects to decreased Polycomb-mediated repression of the T/Brachyury locus and over-activation of T target genes. Binding of the Polycomb repressor complex 2 to T/Brachyury is impaired by the mutated lamin A network, which is unable to properly associate with the locus. This leads to a deregulation of vascular gene expression over time. By connecting a lipodystrophic hotspot lamin A mutation to a disruption of early mesodermal gene expression and defective endothelial differentiation, we propose that the mutation rewires the fate of several lineages, resulting in multi-tissue pathogenic phenotypes.

The Geology and Remarkable Thermal Activity of Norris Geyser Basin, Yellowstone National Park, Wyoming

USGS Publications Warehouse

White, Donald Edward; Hutchinson, Roderick A.; Keith, Terry E.C.

1988-01-01

Norris Geyser Basin, normally shortened to Norris Basin, is adjacent to the north rim of the Yellowstone caldera at the common intersection of the caldera rim and the Norris-Mammoth Corridor, a zone of faults, volcanic vents, and thermal activity that strikes north from the caldera rim to Mammoth Hot Springs. An east-west fault zone terminates the Gallatin Range at its southern end and extends from Hebgen Lake, west of the park, to Norris Basin. No local evidence exists at the surface in Norris Basin for the two oldest Yellowstone volcanic caldera cycles (~2.0 and 1.3 m.y.B.P.). The third and youngest cycle formed the Yellowstone caldera, which erupted the 600,000-year-old Lava Creek Tuff. No evidence is preserved of hydrothermal activity near Norris Basin during the first 300,000.years after the caldera collapse. Glaciation probably removed most of the early evidence, but erratics of hot-spring sinter that had been converted diagenetically to extremely hard, resistant chalcedonic sinter are present as cobbles in and on some moraines and till from the last two glacial stages, here correlated with the early and late stages of the Pinedale glaciation <150,000 years B.P.). Indirect evidence for the oldest hydrothermal system at Norris Basin indicates an age probably older than both stages of Pinedale glaciation. Stream deposits consisting mainly of rounded quartz phenocrysts of the Lava Creek Tuff were subaerial, perhaps in part windblown and redeposited by streams. A few small rounded pebbles are interpreted as chalcedonic sinter of a still older cycle. None of these are precisely dated but are unlikely to be more than 150,000 to 200,000 years old. ...Most studies of active hydrothermal areas have noted chemical differences in fluids and alteration products but have given little attention to differences and models to explain evolution in types. This report, in contrast, emphasizes the kinds of changes in vents and their changing chemical types of waters and then

Streamflow statistics for unregulated and regulated conditions for selected locations on the Upper Yellowstone and Bighorn Rivers, Montana and Wyoming, 1928-2002

USGS Publications Warehouse

Chase, Katherine J.

2014-01-01

Major floods in 1996 and 1997 intensified public debate about the effects of human activities on the Yellowstone River. In 1999, the Yellowstone River Conservation District Council was formed to address conservation issues on the river. The Yellowstone River Conservation District Council partnered with the U.S. Army Corps of Engineers to carry out a cumulative effects study on the main stem of the Yellowstone River. The cumulative effects study is intended to provide a basis for future management decisions within the watershed. Streamflow statistics, such as flow-frequency data calculated for unregulated and regulated streamflow conditions, are a necessary component of the cumulative effects study. The U.S. Geological Survey, in cooperation with the Yellowstone River Conservation District Council and the U.S. Army Corps of Engineers, calculated low-flow frequency data and general monthly and annual statistics for unregulated and regulated streamflow conditions for the Upper Yellowstone and Bighorn Rivers for the 1928–2002 study period; these data are presented in this report. Unregulated streamflow represents flow conditions during the 1928–2002 study period if there had been no water-resources development in the Yellowstone River Basin. Regulated streamflow represents estimates of flow conditions during the 1928–2002 study period if the level of water-resources development existing in 2002 was in place during the entire study period.

Invasion of American bullfrogs along the Yellowstone River

USGS Publications Warehouse

Sepulveda, Adam; Layhee, Megan J.; Stagliano, Dave; Chaffin, Jake; Begley, Allison; Maxell, Bryce A.

2015-01-01

The American bullfrog (Lithobates catesbeianus) is a globally distributed invasive species that was introduced to the Yellowstone River floodplain of Montana. Knowledge about floodplain habitat features that allow for bullfrog persistence and spread will help identify effective control strategies. We used field surveys in 2010, 2012 and 2013 to describe bullfrog spread in the Yellowstone River floodplain and the habitat features that are associated with bullfrog occupancy and colonization. Bullfrogs in our study area expanded from ~ 60 km in 2010 to 106 km in 2013, and are spreading to up- and downstream habitats. The number of breeding sites (i.e., presence of bullfrog eggs or larvae) increased from 12 sites in 2010 to 45 sites in 2013. We found that bullfrogs were associated with deeper waters, emergent vegetation and public-access sites, which are habitat features that characterize permanent waters and describe human-mediated introductions. Control strategies that reduce the hydroperiod of breeding sites may help to limit bullfrog persistence and spread, while an increase in public outreach and education may help prevent further bullfrog introductions at public-access sites.

Modeling ash fall distribution from a Yellowstone supereruption

USGS Publications Warehouse

Mastin, Larry G.; Van Eaton, Alexa R.; Lowenstern, Jacob B.

2014-01-01

We used the volcanic ash transport and dispersion model Ash3d to estimate the distribution of ashfall that would result from a modern-day Plinian supereruption at Yellowstone volcano. The simulations required modifying Ash3d to consider growth of a continent-scale umbrella cloud and its interaction with ambient wind fields. We simulated eruptions lasting 3 days, 1 week, and 1 month, each producing 330 km3 of volcanic ash, dense-rock equivalent (DRE). Results demonstrate that radial expansion of the umbrella cloud is capable of driving ash upwind (westward) and crosswind (N-S) in excess of 1500 km, producing more-or-less radially symmetric isopachs that are only secondarily modified by ambient wind. Deposit thicknesses are decimeters to meters in the northern Rocky Mountains, centimeters to decimeters in the northern Midwest, and millimeters to centimeters on the East, West, and Gulf Coasts. Umbrella cloud growth may explain the extremely widespread dispersal of the ∼640 ka and 2.1 Ma Yellowstone tephra deposits in the eastern Pacific, northeastern California, southern California, and South Texas.

Crustal-scale recycling in caldera complexes and rift zones along the Yellowstone hotspot track: O and Hf isotopic evidence in diverse zircons from voluminous rhyolites of the Picabo volcanic field, Idaho

USGS Publications Warehouse

Drew, Dana L.; Bindeman, Ilya N.; Watts, Kathryn E.; Schmitt, Axel K.; Fu, Bin; McCurry, Michael

2013-01-01

Rhyolites of the Picabo volcanic field (10.4–6.6 Ma) in eastern Idaho are preserved as thick ignimbrites and lavas along the margins of the Snake River Plain (SRP), and within a deep (>3 km) borehole near the central axis of the Yellowstone hotspot track. In this study we present new O and Hf isotope data and U–Pb geochronology for individual zircons, O isotope data for major phenocrysts (quartz, plagioclase, and pyroxene), whole rock Sr and Nd isotope ratios, and whole rock geochemistry for a suite of Picabo rhyolites. We synthesize our new datasets with published Ar–Ar geochronology to establish the eruptive framework of the Picabo volcanic field, and interpret its petrogenetic history in the context of other well-studied caldera complexes in the SRP. Caldera complex evolution at Picabo began with eruption of the 10.44±0.27 Ma (U–Pb) Tuff of Arbon Valley (TAV), a chemically zoned and normal-δ18O (δ18O magma=7.9‰) unit with high, zoned 87Sr/86Sri (0.71488–0.72520), and low-εNd(0) (−18) and εHf(0) (−28). The TAV and an associated post caldera lava flow possess the lowest εNd(0) (−23), indicating ∼40–60% derivation from the Archean upper crust. Normal-δ18O rhyolites were followed by a series of lower-δ18O eruptions with more typical (lower crustal) Sr–Nd–Hf isotope ratios and whole rock chemistry. The voluminous 8.25±0.26 Ma West Pocatello rhyolite has the lowest δ18O value (δ18Omelt=3.3‰), and we correlate it to a 1,000 m thick intracaldera tuff present in the INEL-1 borehole (with published zircon ages 8.04–8.35 Ma, and similarly low-δ18O zircon values). The significant (4–5‰) decrease in magmatic-δ18O values in Picabo rhyolites is accompanied by an increase in zircon δ18O heterogeneity from ∼1‰ variation in the TAV to >5‰ variation in the late-stage low-δ18O rhyolites, a trend similar to what is characteristic of Heise and Yellowstone, and which indicates remelting of variably hydrothermally altered tuffs

Mid-ocean ridge jumps associated with hotspot magmatism

NASA Astrophysics Data System (ADS)

Mittelstaedt, Eric; Ito, Garrett; Behn, Mark D.

2008-02-01

Hotspot-ridge interaction produces a wide range of phenomena including excess crustal thickness, geochemical anomalies, off-axis volcanic ridges and ridge relocations or jumps. Ridges are recorded to have jumped toward many hotspots including, Iceland, Discovery, Galápagos, Kerguelen and Tristan de Cuhna. The causes of ridge jumps likely involve a number of interacting processes related to hotspots. One such process is reheating of the lithosphere as magma penetrates it to feed near-axis volcanism. We study this effect by using the hybrid, finite-element code, FLAC, to simulate two-dimensional (2-D, cross-section) viscous mantle flow, elasto-plastic deformation of the lithosphere and heat transport in a ridge setting near an off-axis hotspot. Heating due to magma transport through the lithosphere is implemented within a hotspot region of fixed width. To determine the conditions necessary to initiate a ridge jump, we vary four parameters: hotspot magmatic heating rate, spreading rate, seafloor age at the location of the hotspot and ridge migration rate. Our results indicate that the hotspot magmatic heating rate required to initiate a ridge jump increases non-linearly with increasing spreading rate and seafloor age. Models predict that magmatic heating, itself, is most likely to cause jumps at slow spreading rates such as at the Mid-Atlantic Ridge on Iceland. In contrast, despite the higher magma flux at the Galápagos hotspot, magmatic heating alone is probably insufficient to induce a ridge jump at the present-day due to the intermediate ridge spreading rate of the Galápagos Spreading Center. The time required to achieve a ridge jump, for fixed or migrating ridges, is found to be on the order of 10 5-10 6 years. Simulations that incorporate ridge migration predict that after a ridge jump occurs the hotspot and ridge migrate together for time periods that increase with magma flux. Model results also suggest a mechanism for ridge reorganizations not related to

Meiotic recombination hotspots - a comparative view.

PubMed

Choi, Kyuha; Henderson, Ian R

2015-07-01

During meiosis homologous chromosomes pair and undergo reciprocal genetic exchange, termed crossover. Meiotic recombination has a profound effect on patterns of genetic variation and is an important tool during crop breeding. Crossovers initiate from programmed DNA double-stranded breaks that are processed to form single-stranded DNA, which can invade a homologous chromosome. Strand invasion events mature into double Holliday junctions that can be resolved as crossovers. Extensive variation in the frequency of meiotic recombination occurs along chromosomes and is typically focused in narrow hotspots, observed both at the level of DNA breaks and final crossovers. We review methodologies to profile hotspots at different steps of the meiotic recombination pathway that have been used in different eukaryote species. We then discuss what these studies have revealed concerning specification of hotspot locations and activity and the contributions of both genetic and epigenetic factors. Understanding hotspots is important for interpreting patterns of genetic variation in populations and how eukaryotic genomes evolve. In addition, manipulation of hotspots will allow us to accelerate crop breeding, where meiotic recombination distributions can be limiting. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

Human population in the biodiversity hotspots.

PubMed

Cincotta, R P; Wisnewski, J; Engelman, R

2000-04-27

Biologists have identified 25 areas, called biodiversity hotspots, that are especially rich in endemic species and particularly threatened by human activities. The human population dynamics of these areas, however, are not well quantified. Here we report estimates of key demographic variables for each hotspot, and for three extensive tropical forest areas that are less immediately threatened. We estimate that in 1995 more than 1.1 billion people, nearly 20% of world population, were living within the hotspots, an area covering about 12% of Earth's terrestrial surface. We estimate that the population growth rate in the hotspots (1995-2000) is 1.8% yr(-1), substantially higher than the population growth rate of the world as a whole (1.3% yr(-1)) and above that of the developing countries (1.6% yr(-1)). These results suggest that substantial human-induced environmental changes are likely to continue in the hotspots and that demographic change remains an important factor in global biodiversity conservation. The results also underline the potential conservation significance of the continuing worldwide declines in human fertility and of policies and programs that influence human migration.

75 FR 54419 - Environmental Impact Statement: Yellowstone County, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-07

... be prepared for a proposed highway project in Yellowstone County, Montana. FOR FURTHER INFORMATION... that an EIS will be prepared on the re-scoped, proposed project. These improvements are considered... be prepared for a proposal to construct a bypass route north of the city of Billings. Funding...

NIMS: hotspots on Io during G2

NASA Technical Reports Server (NTRS)

1996-01-01

The Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft imaged Io at high spectral resolution at a range of 439,000 km (275,000 miles) during the G2 encounter on 7 September 1996. This image shows (on the right) Io as seen in the infrared by NIMS. The image on the left shows the same view from Voyager in 1979. This NIMS image can be compared to the NIMS images from the G1 orbit (June 1996) to monitor changes on Io. The NIMS image is at 4.9 microns, showing thermal emissions from the hotspots. The brightness of the pixels is a function of size and temperature.

At least 10 hotspots have been identified and can be matched with surface features. An accurate determination of the position of the hotspot in the vicinity of Shamash Patera is pending. Hotspots are seen in the vicinity of Prometheus, Volund and Marduk, all sites of volcanic plume activity during the Galileo encounters, and also of active plumes in 1979. Temperatures and areas have been calculated for the hotspots shown. Temperatures range from 828 K (1031 F) to 210 K (- 81.4 F). The lowest temperature is significantly higher than the Io background (non-hotspot) surface temperature of about 100 K (-279 F). Hotspot areas range from 6.5 square km (2.5 sq miles) to 40,000 sq km (15,400 sq miles). The hottest hotspots have smallest areas, and the cooler hotspots have the largest areas. NIMS is continuing to observe Io to monitor volcanic activity throughout the Galileo mission.

The Galileo mission is managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, D.C.

This image and other images and data received from Galileo are posted on the Galileo mission home page on the World Wide Web at http://galileo.jpl.nasa.gov.

Use of lodgepole pine cover types by Yellowstone grizzly bears

USGS Publications Warehouse

Mattson, D.J.

1997-01-01

Lodgepole pine (Pinus contorta) forests are a large and dynamic part of grizzly bear (Ursus arctos) habitat in the Yellowstone ecosystem. Research in other areas suggests that grizzly bears select for young open forest stands, especially for grazing and feeding on berries. Management guidelines accordingly recommend timber harvest as a technique for improving habitat in areas potentially dominated by lodgepole pine. In this paper I examine grizzly bear use of lodgepole pine forests in the Yellowstone area, and test several hypotheses with relevance to a new generation of management guidelines. Differences in grizzly bear selection of lodgepole pine cover types (defined on the basis of stand age and structure) were not pronounced. Selection furthermore varied among years, areas, and individuals. Positive selection for any lodgepole pine type was uncommon. Estimates of selection took 5-11 years or 4-12 adult females to stabilize, depending upon the cover type. The variances of selection estimates tended to stabilize after 3-5 sample years, and were more-or-less stable to slightly increasing with progressively increased sample area. There was no conclusive evidence that Yellowstone's grizzlies favored young (<40 yr) stands in general or for their infrequent use of berries. On the other hand, these results corroborated previous observations that grizzlies favored open and/or young stands on wet and fertile sites for grazing. These results also supported the proposition that temporally and spatially robust inferences require extensive, long-duration studies, especially for wide-ranging vertebrates like grizzly bears.

Willow on Yellowstone's northern range: evidence for a trophic cascade?

PubMed

Beyer, Hawthorne L; Merrill, Evelyn H; Varley, Nathan; Boyce, Mark S

2007-09-01

Reintroduction of wolves (Canis lupus) to Yellowstone National Park in 1995-1996 has been argued to promote a trophic cascade by altering elk (Cervus elaphus) density, habitat-selection patterns, and behavior that, in turn, could lead to changes within the plant communities used by elk. We sampled two species of willow (Salix boothii and S. geyeriana) on the northern winter range to determine whether (1) there was quantitative evidence of increased willow growth following wolf reintroduction, (2) browsing by elk affected willow growth, and (3) any increase in growth observed was greater than that expected by climatic and hydrological factors alone, thereby indicating a trophic cascade caused by wolves. Using stem sectioning techniques to quantify historical growth patterns we found an approximately twofold increase in stem growth-ring area following wolf reintroduction for both species of willow. This increase could not be explained by climate and hydrological factors alone; the presence of wolves on the landscape was a significant predictor of stem growth above and beyond these abiotic factors. Growth-ring area was positively correlated with the previous year's ring area and negatively correlated with the percentage of twigs browsed from the stem during the winter preceding growth, indicating that elk browse impeded stem growth. Our results are consistent with the hypothesis of a behaviorally mediated trophic cascade on Yellowstone's northern winter range following wolf reintroduction. We suggest that the community-altering effects of wolf restoration are an endorsement of ecological-process management in Yellowstone National Park.

Multiscale Genetic Structure of Yellowstone Cutthroat Trout in the Upper Snake River Basin.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cegelski, Christine C.; Campbell, Matthew R.

2006-05-30

Populations of Yellowstone cutthroat trout Oncorhynchus clarkii bouvierii have declined throughout their native range as a result of habitat fragmentation, overharvest, and introductions of nonnative trout that have hybridized with or displaced native populations. The degree to which these factors have impacted the current genetic population structure of Yellowstone cutthroat trout populations is of primary interest for their conservation. In this study, we examined the genetic diversity and genetic population structure of Yellowstone cutthroat trout in Idaho and Nevada with data from six polymorphic microsatellite loci. A total of 1,392 samples were analyzed from 45 sample locations throughout 11 majormore » river drainages. We found that levels of genetic diversity and genetic differentiation varied extensively. The Salt River drainage, which is representative of the least impacted migration corridors in Idaho, had the highest levels of genetic diversity and low levels of genetic differentiation. High levels of genetic differentiation were observed at similar or smaller geographic scales in the Portneuf River, Raft River, and Teton River drainages, which are more altered by anthropogenic disturbances. Results suggested that Yellowstone cutthroat trout are naturally structured at the major river drainage level but that habitat fragmentation has altered this structuring. Connectivity should be restored via habitat restoration whenever possible to minimize losses in genetic diversity and to preserve historical processes of gene flow, life history variation, and metapopulation dynamics. However, alternative strategies for management and conservation should also be considered in areas where there is a strong likelihood of nonnative invasions or extensive habitat fragmentation that cannot be easily ameliorated.« less

Automated Selection of Hotspots (ASH): enhanced automated segmentation and adaptive step finding for Ki67 hotspot detection in adrenal cortical cancer.

PubMed

Lu, Hao; Papathomas, Thomas G; van Zessen, David; Palli, Ivo; de Krijger, Ronald R; van der Spek, Peter J; Dinjens, Winand N M; Stubbs, Andrew P

2014-11-25

In prognosis and therapeutics of adrenal cortical carcinoma (ACC), the selection of the most active areas in proliferative rate (hotspots) within a slide and objective quantification of immunohistochemical Ki67 Labelling Index (LI) are of critical importance. In addition to intratumoral heterogeneity in proliferative rate i.e. levels of Ki67 expression within a given ACC, lack of uniformity and reproducibility in the method of quantification of Ki67 LI may confound an accurate assessment of Ki67 LI. We have implemented an open source toolset, Automated Selection of Hotspots (ASH), for automated hotspot detection and quantification of Ki67 LI. ASH utilizes NanoZoomer Digital Pathology Image (NDPI) splitter to convert the specific NDPI format digital slide scanned from the Hamamatsu instrument into a conventional tiff or jpeg format image for automated segmentation and adaptive step finding hotspots detection algorithm. Quantitative hotspot ranking is provided by the functionality from the open source application ImmunoRatio as part of the ASH protocol. The output is a ranked set of hotspots with concomitant quantitative values based on whole slide ranking. We have implemented an open source automated detection quantitative ranking of hotspots to support histopathologists in selecting the 'hottest' hotspot areas in adrenocortical carcinoma. To provide wider community easy access to ASH we implemented a Galaxy virtual machine (VM) of ASH which is available from http://bioinformatics.erasmusmc.nl/wiki/Automated_Selection_of_Hotspots . The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_216.

Earthshots: Satellite images of environmental change – Yellowstone National Park, USA

USGS Publications Warehouse

Adamson, Thomas

2014-01-01

Yellowstone is representative of temperate mountain ecosystems throughout western North America. What is learned from the massive 1988 fires and subsequent recovery of these ecosystems can be applied to other regions.

Dynamic malaria hotspots in an open cohort in western Kenya.

PubMed

Platt, Alyssa; Obala, Andrew A; MacIntyre, Charlie; Otsyula, Barasa; Meara, Wendy Prudhomme O'

2018-01-12

Malaria hotspots, defined as areas where transmission intensity exceeds the average level, become more pronounced as transmission declines. Targeting hotspots may accelerate reductions in transmission and could be pivotal for malaria elimination. Determinants of hotspot location, particularly of their movement, are poorly understood. We used spatial statistical methods to identify foci of incidence of self-reported malaria in a large census population of 64,000 people, in 8,290 compounds over a 2.5-year study period. Regression models examine stability of hotspots and identify static and dynamic correlates with their location. Hotspot location changed over short time-periods, rarely recurring in the same area. Hotspots identified in spring versus fall season differed in their stability. Households located in a hotspot in the fall were more likely to be located in a hotspot the following fall (RR = 1.77, 95% CI: 1.66-1.89), but the opposite was true for compounds in spring hotspots (RR = 0.15, 95% CI: 0.08-0.28). Location within a hotspot was related to environmental and static household characteristics such as distance to roads or rivers. Human migration into a household was correlated with risk of hotspot membership, but the direction of the association differed based on the origin of the migration event.

Climate and reproduction of grizzly bears in Yellowstone National Park

USGS Publications Warehouse

Picton, Harold D.

1978-01-01

Controversy surrounds the conflicts between the requirements of human safety and the preservation of grizzly bears (Ursus arctos horribilis) in western North America. It has been difficult to separate the effect of factors such as the closure of garbage dumps from that of the climate. It has also proved difficult to relate climatic data to changes in the populations of large mammals. I report here a correlation of climatic change with fluctuations in the sizes of litters of grizzly bears born in Yellowstone National Park, Wyoming, during 1958–1976. The decrease in litter sizes observed since the closure of garbage dumps seems to be largely a consequence of unfavourable weather during the periods of the final fattening of the mother, winter sleep, birth, lactation and early spring foraging. This study represents one of the few times that the effects of climate have been demonstrated for large omnivorous or carnivorous mammals.

Aerial survey methodology for bison population estimation in Yellowstone National Park

USGS Publications Warehouse

Hess, Steven C.

2002-01-01

I developed aerial survey methods for statistically rigorous bison population estimation in Yellowstone National Park to support sound resource management decisions and to understand bison ecology. Survey protocols, data recording procedures, a geographic framework, and seasonal stratifications were based on field observations from February 1998-September 2000. The reliability of this framework and strata were tested with long-term data from 1970-1997. I simulated different sample survey designs and compared them to high-effort censuses of well-defined large areas to evaluate effort, precision, and bias. Sample survey designs require much effort and extensive information on the current spatial distribution of bison and therefore do not offer any substantial reduction in time and effort over censuses. I conducted concurrent ground surveys, or 'double sampling' to estimate detection probability during aerial surveys. Group size distribution and habitat strongly affected detection probability. In winter, 75% of the groups and 92% of individual bison were detected on average from aircraft, while in summer, 79% of groups and 97% of individual bison were detected. I also used photography to quantify the bias due to counting large groups of bison accurately and found that undercounting increased with group size and could reach 15%. I compared survey conditions between seasons and identified optimal time windows for conducting surveys in both winter and summer. These windows account for the habitats and total area bison occupy, and group size distribution. Bison became increasingly scattered over the Yellowstone region in smaller groups and more occupied unfavorable habitats as winter progressed. Therefore, the best conditions for winter surveys occur early in the season (Dec-Jan). In summer, bison were most spatially aggregated and occurred in the largest groups by early August. Low variability between surveys and high detection probability provide population estimates

Project HOTSPOT: Borehole geophysics log interpretation from the Snake River Plain, Idaho

NASA Astrophysics Data System (ADS)

Lee, M. D.; Schmitt, D. R.; Chen, X.; Shervais, J. W.; Liberty, L. M.; Potter, K. E.; Kessler, J. A.

2013-12-01

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberely, and (3) Mountain Home. The most eastern drill hole is Kimama located along the central volcanic axis of the SRP and documents basaltic volcanism. The Kimberely drill hole was selected to document continuous volcanism when analysed in conjunction with the Kimama drill hole and is located near the margin of the plain. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. A suite of ground and borehole geophysical surveys were carried out within the SRP between 2010 and 2012. The borehole geophysics logs included gamma ray (spectral and natural), neutron hydrogen index, electrical resistivity, magnetic susceptibility, ultrasonic borehole televiewer imaging, full waveform sonic, and vertical seismic profile. The borehole geophysics logs were qualitatively assessed through visual interpretation of lithological horizons and quantitatively through physical property specialized software and digital signal processing automated filtering process to identify step functions and high frequency anomalies. Preliminary results were published by Schmitt et al. (2012), Potter et al. (2012), and Shervais et al. (2013). The results are continuously being enhanced as more information is qualitatively and quantitatively delineated from the borehole geophysics logs. Each drill hole encounters three principal units: massive basalt flows, rhyolite, and sediments. Basalt has a low to moderate porosity and is

Imbalance aware lithography hotspot detection: a deep learning approach

NASA Astrophysics Data System (ADS)

Yang, Haoyu; Luo, Luyang; Su, Jing; Lin, Chenxi; Yu, Bei

2017-07-01

With the advancement of very large scale integrated circuits (VLSI) technology nodes, lithographic hotspots become a serious problem that affects manufacture yield. Lithography hotspot detection at the post-OPC stage is imperative to check potential circuit failures when transferring designed patterns onto silicon wafers. Although conventional lithography hotspot detection methods, such as machine learning, have gained satisfactory performance, with the extreme scaling of transistor feature size and layout patterns growing in complexity, conventional methodologies may suffer from performance degradation. For example, manual or ad hoc feature extraction in a machine learning framework may lose important information when predicting potential errors in ultra-large-scale integrated circuit masks. We present a deep convolutional neural network (CNN) that targets representative feature learning in lithography hotspot detection. We carefully analyze the impact and effectiveness of different CNN hyperparameters, through which a hotspot-detection-oriented neural network model is established. Because hotspot patterns are always in the minority in VLSI mask design, the training dataset is highly imbalanced. In this situation, a neural network is no longer reliable, because a trained model with high classification accuracy may still suffer from a high number of false negative results (missing hotspots), which is fatal in hotspot detection problems. To address the imbalance problem, we further apply hotspot upsampling and random-mirror flipping before training the network. Experimental results show that our proposed neural network model achieves comparable or better performance on the ICCAD 2012 contest benchmark compared to state-of-the-art hotspot detectors based on deep or representative machine leaning.

Modelling Hotspots for Invasive Alien Plants in India

PubMed Central

Adhikari, Dibyendu; Tiwary, Raghuvar; Barik, Saroj Kanta

2015-01-01

Identification of invasion hotspots that support multiple invasive alien species (IAS) is a pre-requisite for control and management of invasion. However, till recently it remained a methodological challenge to precisely determine such invasive hotspots. We identified the hotspots of alien species invasion in India through Ecological Niche Modelling (ENM) using species occurrence data from the Global Biodiversity Information Facility (GBIF). The predicted area of invasion for selected species were classified into 4 categories based on number of model agreements for a region i.e. high, medium, low and very low. About 49% of the total geographical area of India was predicted to be prone to invasion at moderate to high levels of climatic suitability. The intersection of anthropogenic biomes and ecoregions with the regions of 'high' climatic suitability was classified as hotspot of alien plant invasion. Nineteen of 47 ecoregions of India, harboured such hotspots. Most ecologically sensitive regions of India, including the 'biodiversity hotspots' and coastal regions coincide with invasion hotspots, indicating their vulnerability to alien plant invasion. Besides demonstrating the usefulness of ENM and open source data for IAS management, the present study provides a knowledge base for guiding the formulation of an effective policy and management strategy for controlling the invasive alien species. PMID:26230513

Modelling Hotspots for Invasive Alien Plants in India.

PubMed

Adhikari, Dibyendu; Tiwary, Raghuvar; Barik, Saroj Kanta

2015-01-01

Identification of invasion hotspots that support multiple invasive alien species (IAS) is a pre-requisite for control and management of invasion. However, till recently it remained a methodological challenge to precisely determine such invasive hotspots. We identified the hotspots of alien species invasion in India through Ecological Niche Modelling (ENM) using species occurrence data from the Global Biodiversity Information Facility (GBIF). The predicted area of invasion for selected species were classified into 4 categories based on number of model agreements for a region i.e. high, medium, low and very low. About 49% of the total geographical area of India was predicted to be prone to invasion at moderate to high levels of climatic suitability. The intersection of anthropogenic biomes and ecoregions with the regions of 'high' climatic suitability was classified as hotspot of alien plant invasion. Nineteen of 47 ecoregions of India, harboured such hotspots. Most ecologically sensitive regions of India, including the 'biodiversity hotspots' and coastal regions coincide with invasion hotspots, indicating their vulnerability to alien plant invasion. Besides demonstrating the usefulness of ENM and open source data for IAS management, the present study provides a knowledge base for guiding the formulation of an effective policy and management strategy for controlling the invasive alien species.

Examining winter visitor use in Yellowstone National Park

Treesearch

Mae A. Davenport; Wayne A. Freimund; William T. Borrie; Robert E. Manning; William A. Valliere; Benjamin Wang

2000-01-01

This research was designed to assist the managers of Yellowstone National Park (YNP) in their decision making about winter visitation. The focus of this report is on winter use patterns and winter visitor preferences. It is the author’s hope that this information will benefit both the quality of winter experiences and the stewardship of the park resources. This report...

Hotspot Motion, Before and After the Hawaiian-Emperor Bend

NASA Astrophysics Data System (ADS)

Tarduno, J. A.; Bono, R. K.

2014-12-01

Hawaiian hotspot motion of >40 mm/yr is best documented by paleomagnetic investigations of basalt cores recovered by ocean drilling of the Emperor seamounts during ODP Leg 197 (Tarduno et al., 2003). These data indicate that the trend of the Emperor Seamounts dominantly records motion of the hotspot in the mantle, further suggesting that the great Hawaiian-Emperor bend (HEB) reflects mainly a change in hotspot motion. Data used for Pacific "absolute plate motion models" for times before the age of the HEB are also internally inconsistent with a fixed hotspot assumption; at present the best way to estimate Pacific absolute plate motion prior to the HEB bend is through use of predictions derived from plate circuits (e.g. Doubrovine and Tarduno, 2008). These analyses predict much less motion for the hotspot responsible for the Louisville Seamount chain, as has been observed by paleomagnetic analyses of cores recovered by IODP Expedition 330 (Koppers et al., 2012). Together, the ocean drilling data sets favor hotspot-specific processes to explain high drift rates, such as the model whereby the Hawaiian mantle plume was captured by a ridge in the Late Cretaceous, and subsequent changes in sub-Pacific mantle flow resulted in the trend of the Emperor Seamounts (Tarduno et al., 2009). However, the question of whether there is a smaller signal of motion between groups of hotspots remains. Plate circuit analyses yield a small discrepancy between predicted and actual hotspot locations for times between ca. 47 Ma and 10 Ma that could be a signal of continued southward migration of the Hawaiian hotspot. Alternatively, this could reflect the motion of the group of Indo-Atlantic hotspots relative to Hawaii. New paleomagnetic data from Midway Atoll (ca. 27 Ma) suggests little difference with the present-day latitude of the plume, indicating that the rate of motion of either the Hawaiian hotspot, or the Indo-Atlantic hotspot group, was about 15 mm/yr between 47 and 27 Ma. This

Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting

USGS Publications Warehouse

Waite, Gregory P.; Schutt, D.L.; Smith, Robert B.

2005-01-01

Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume-induced radial strain, suggesting that any contribution of gravitationally spreading plume material is undetectably small with respect to the plate motion velocity. Two stations within Yellowstone have splitting measurements indicating the apparent fast anisotropy direction (ϕ) is nearly perpendicular to plate motion. These stations are ∼30 km from stations with ϕ parallel to plate motion. The 70° rotation over 30 km suggests a shallow source of anisotropy; however, split times for these stations are more than 2 s. We suggest melt-filled, stress-oriented cracks in the lithosphere are responsible for the anomalous ϕ orientations within Yellowstone. Stations southeast of Yellowstone have measurements of ϕ oriented NNW to WNW at high angles to the plate motion direction. The Archean lithosphere beneath these stations may have significant anisotropy capable of producing the observed splitting.

Development of a Global Agricultural Hotspot Detection and Early Warning System

NASA Astrophysics Data System (ADS)

Lemoine, G.; Rembold, F.; Urbano, F.; Csak, G.

2015-12-01

The number of web based platforms for crop monitoring has grown rapidly over the last years and anomaly maps and time profiles of remote sensing derived indicators can be accessed online thanks to a number of web based portals. However, while these systems make available a large amount of crop monitoring data to the agriculture and food security analysts, there is no global platform which provides agricultural production hotspot warning in a highly automatic and timely manner. Therefore a web based system providing timely warning evidence as maps and short narratives is currently under development by the Joint Research Centre. The system (called "HotSpot Detection System of Agriculture Production Anomalies", HSDS) will focus on water limited agricultural systems worldwide. The automatic analysis of relevant meteorological and vegetation indicators at selected administrative units (Gaul 1 level) will trigger warning messages for the areas where anomalous conditions are observed. The level of warning (ranging from "watch" to "alert") will depend on the nature and number of indicators for which an anomaly is detected. Information regarding the extent of the agricultural areas concerned by the anomaly and the progress of the agricultural season will complement the warning label. In addition, we are testing supplementary detailed information from other sources for the areas triggering a warning. These regard the automatic web-based and food security-tailored analysis of media (using the JRC Media Monitor semantic search engine) and the automatic detection of active crop area using Sentinel 1, upcoming Sentinel-2 and Landsat 8 imagery processed in Google Earth Engine. The basic processing will be fully automated and updated every 10 days exploiting low resolution rainfall estimates and satellite vegetation indices. Maps, trend graphs and statistics accompanied by short narratives edited by a team of crop monitoring experts, will be made available on the website on a

Taming of a Wild Research Well in Yellowstone National Park during November 1992

USGS Publications Warehouse

Fournier, Robert O.; Moore, Michael M.

2008-01-01

Much of our current understanding of Yellowstone's geothermal areas comes from research drilling by the USGS during 1967 and 1968. Thirteen wells were drilled in thermal areas around the park. Scientists collected waters and rocks, measured temperatures and pressures and performed other tests to characterize the shallow subsurface at Yellowstone. Most wells were plugged and abandoned, but a few were left open for future scientific tests and sampling. One of those wells, the Y8, was located at Biscuit Basin, 2 miles north of Old Faithful. In November 1992, a valve at the ground surface failed, leading to a blowout, an uncontrolled eruption of steam and hot water. The USGS and Yellowstone National Park worked with a drilling contractor to control the flow and plug the well. The lead scientist, Robert Fournier, used video taken by the drilling contractor, Tonto Services, to create this fascinating 28-minute-long film. It is followed by a short news story by CNN, also from November 1992. Fifteen years later, we felt that the video was of sufficient scientific and historical interest that it was worth publishing as a USGS Open-file report, where it can be accessed into the future. Enjoy!

Sagebrush-ungulate relationships on the Northern Yellowstone Winter Range

Treesearch

Carl L. Wambolt

2005-01-01

Sagebrush (Artemisia) taxa have historically been the landscape dominants over much of the Northern Yellowstone Winter Range (NYWR). Their importance to the unnaturally large ungulate populations on the NYWR throughout the twentieth century has been recognized since the 1920s. Sagebrush-herbivore ecology has been the focus of research on the NYWR for...

Yellowstone bison genetics: let us move forward

USGS Publications Warehouse

Halbert, Natalie D.; Gogan, Peter J.P.; Hedrick, Philip W.; Wahl, Jacquelyn M.; Derr, James N.

2012-01-01

White and Wallen (2012) disagree with the conclusions and suggestions made in our recent assessment of population structure among Yellowstone National Park (YNP) bison based on 46 autosomal microsatellite loci in 661 animals (Halbert et al. 2012). First, they suggest that "the existing genetic substructure (that we observed) was artificially created." Specifically, they suggest that the substructure observed between the northern and central populations is the result of human activities, both historical and recent. In fact, the genetic composition of all known existing bison herds was created by, or has been influenced by, anthropogenic activities, although this obviously does not reduce the value of these herds for genetic conservation (Dratch and Gogan 2010). As perspective, many, if not most, species of conservation concern have been influenced by human actions and as a result currently exist as isolated populations. However, it is quite difficult to distinguish between genetic differences caused by human actions and important ancestral variation contained in separate populations without data from early time periods. Therefore, to not lose genetic variation that may be significant or indicative of important genetic variation, the generally acceptable management approach is to attempt to retain this variation based on the observed population genetic subdivision (Hedrick et al. 1986).

Delineating Spatial Patterns in the Yellowstone Hydrothermal System using Geothermometry

NASA Astrophysics Data System (ADS)

King, J.; Hurwitz, S.; Lowenstern, J. B.

2015-12-01

Yellowstone National Park is unmatched with regard to its quantity of active hydrothermal features. Origins of thermal waters in its geyser basins have been traced to mixing of a deep parent water with meteoric waters in shallow local reservoirs (Fournier, 1989). A mineral-solution equilibrium model was developed to calculate water-rock chemical re-equilibration temperatures in these shallow reservoirs. We use the GeoT program, which uses water composition data as input to calculate saturation indices of selected minerals; the "best-clustering" minerals are then statistically determined to infer reservoir temperatures (Spycher et al., 2013). We develop the method using water composition data from Heart Lake Geyser Basin (HLGB), for which both chemical and isotopic geothermometers predict a reservoir water temperature of 205°C ± 10°C (Lowenstern et al., 2012), and minerals found in drill cores in Yellowstone's geyser basins. We test the model for sensitivity to major element composition, pH, Total Inorganic Carbon (TIC) and selected minerals to optimize model parameters. Calculated temperatures are most accurate at pH values below 9.0, and closely match the equilibrium saturation indices of quartz, stilbite, microcline, and albite. The model is optimized with a TIC concentration that is consistent with the mass of diffuse CO2 flux in HLGB (Lowenstern et al., 2012). We then use water compositions from other thermal basins in Yellowstone in search of spatial variations in reservoir temperatures. We then compare the calculated temperatures with various SiO2 and cation geothermometers.

Possible effects of elk harvest on fall distribution of grizzly bears in the Greater Yellowstone Ecosystem

USGS Publications Warehouse

Haroldson, M.A.; Schwartz, C.C.; Cherry, S.; Moody, D.

2004-01-01

 The tradition of early elk (Cervus elaphus) hunting seasons adjacent to Yellowstone National Park (YNP), USA, provides grizzly bears (Ursus arctos horribilis) with ungulate remains left by hunters. We investigated the fall (Aug–Oct) distribution of grizzly bears relative to the boundaries of YNP and the opening of September elk hunting seasons. Based on results from exact tests of conditional independence, we estimated the odds of radiomarked bears being outside YNP during the elk hunt versus before the hunt. Along the northern boundary, bears were 2.40 times more likely to be outside YNP during the hunt in good whitebark pine (Pinus albicaulis) seed-crop years and 2.72 times more likely in poor seed-crop years. The level of confidence associated with 1-sided confidence intervals with a lower endpoint of 1 was approximately 94% in good seed-crop years and 61% in poor years. Along the southern boundary of YNP, radiomarked bears were 2.32 times more likely to be outside the park during the hunt in good whitebark pine seed-crop years and 4.35 times more likely in poor seed-crop years. The level of confidence associated with 1-sided confidence intervals with a lower endpoint of 1 was approximately 93% in both cases. Increased seasonal bear densities and human presence in early hunt units increases potential for conflicts between bears and hunters. Numbers of reported hunting-related grizzly bear mortalities have increased in the Greater Yellowstone Ecosystem (GYE) during the last decade, and nearly half of this increase is due to bear deaths occurring in early hunt units during September. Human-caused grizzly bear mortality thresholds established by the U.S. Fish and Wildlife Service (USFWS) have not been exceeded in recent years. This is because agency actions have reduced other sources of human-caused mortalities, and because population parameters that mortality thresholds are based on have increased. Agencies must continue to monitor and manage hunter

Grizzly bear management in Yellowstone National Park: The heart of recovery in the Yellowstone Ecosystem

USGS Publications Warehouse

Schwartz, C.C.; Gunther, K.; McCullough, Dale R.; Kaji, Koichi; Yamanaka, Masami

2006-01-01

Grizzly bear (Ursus arctos) management in the Greater Yellowstone Ecosystem (GYE) in the past quarter century has resulted in more than doubling of the population from around 200 to more than 500, expansion of range back into habitats where the bear has extirpated more than a century ago, and a move toward removal from the U.S. Endangered Species list. At the center of this success story are the management programs in Yellowstone National Park (YNP). Regulations that restrict human activity, camping, and food storage, elimination of human food and garbage as attractants, and ranger attendance of roadside bears have all resulted in the population of grizzlies in YNP approaching carrying capacity. Recent studies suggest, however, that YNP alone is too small to support the current population, making management beyond the park boundary important and necessary to the demographics of the population as a whole. Demographic analyses suggest a source-sink dynamic exists within the GYE, with YNP and lands outside the park within the Grizzly Bear Recovery Zone (RZ) representing source habitats, whereas lands beyond the RZ constitute sinks. The source-sink demography in the GYE is indicative of carnivore conservation issues worldwide where many national parks or preserves designed to protect out natural resources are inadequate in size or shape to provide all necessary life history requirements for these wide-ranging species. Additionally, wide-ranging behavior and long-distance dispersal seem inherent to large carnivores, so mortality around the edges is virtually inevitable, and conservation in the GYE is inextricably linked to management regimes not only within YNP, but within the GYE as a whole. We discuss those needs here.

Mapping temperature and radiant geothermal heat flux anomalies in the Yellowstone geothermal system using ASTER thermal infrared data

USGS Publications Warehouse

Vaughan, R. Greg; Lowenstern, Jacob B.; Keszthelyi, Laszlo P.; Jaworowski, Cheryl; Heasler, Henry

2012-01-01

The purpose of this work was to use satellite-based thermal infrared (TIR) remote sensing data to measure, map, and monitor geothermal activity within the Yellowstone geothermal area to help meet the missions of both the U.S. Geological Survey Yellowstone Volcano Observatory and the Yellowstone National Park Geology Program. Specifically, the goals were to: 1) address the challenges of remotely characterizing the spatially and temporally dynamic thermal features in Yellowstone by using nighttime TIR data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and 2) estimate the temperature, geothermal radiant emittance, and radiant geothermal heat flux (GHF) for Yellowstone’s thermal areas (both Park wide and for individual thermal areas). ASTER TIR data (90-m pixels) acquired at night during January and February, 2010, were used to estimate surface temperature, radiant emittance, and radiant GHF from all of Yellowstone’s thermal features, produce thermal anomaly maps, and update field-based maps of thermal areas. A background subtraction technique was used to isolate the geothermal component of TIR radiance from thermal radiance due to insolation. A lower limit for the Yellowstone’s total radiant GHF was established at ~2.0 GW, which is ~30-45% of the heat flux estimated through geochemical (Cl-flux) methods. Additionally, about 5 km2 was added to the geodatabase of mapped thermal areas. This work provides a framework for future satellite-based thermal monitoring at Yellowstone as well as exploration of other volcanic / geothermal systems on a global scale.

Evolutionary hotspots in the Mojave Desert

USGS Publications Warehouse

Vandergast, Amy G.; Inman, Richard D.; Barr, Kelly R.; Nussear, Kenneth E.; Esque, Todd C.; Hathaway, Stacie A.; Wood, Dustin A.; Medica, Philip A.; Breinholt, Jesse W.; Stephen, Catherine L.; Gottscho, Andrew D.; Marks, Sharyn B.; Jennings, W. Bryan; Fisher, Robert N.

2013-01-01

Genetic diversity within species provides the raw material for adaptation and evolution. Just as regions of high species diversity are conservation targets, identifying regions containing high genetic diversity and divergence within and among populations may be important to protect future evolutionary potential. When multiple co-distributed species show spatial overlap in high genetic diversity and divergence, these regions can be considered evolutionary hotspots. We mapped spatial population genetic structure for 17 animal species across the Mojave Desert, USA. We analyzed these in concurrence and located 10 regions of high genetic diversity, divergence or both among species. These were mainly concentrated along the western and southern boundaries where ecotones between mountain, grassland and desert habitat are prevalent, and along the Colorado River. We evaluated the extent to which these hotspots overlapped protected lands and utility-scale renewable energy development projects of the Bureau of Land Management. While 30–40% of the total hotspot area was categorized as protected, between 3–7% overlapped with proposed renewable energy project footprints, and up to 17% overlapped with project footprints combined with transmission corridors. Overlap of evolutionary hotspots with renewable energy development mainly occurred in 6 of the 10 identified hotspots. Resulting GIS-based maps can be incorporated into ongoing landscape planning efforts and highlight specific regions where further investigation of impacts to population persistence and genetic connectivity may be warranted.

Bayesian Inference of Shared Recombination Hotspots Between Humans and Chimpanzees

PubMed Central

Wang, Ying; Rannala, Bruce

2014-01-01

Recombination generates variation and facilitates evolution. Recombination (or lack thereof) also contributes to human genetic disease. Methods for mapping genes influencing complex genetic diseases via association rely on linkage disequilibrium (LD) in human populations, which is influenced by rates of recombination across the genome. Comparative population genomic analyses of recombination using related primate species can identify factors influencing rates of recombination in humans. Such studies can indicate how variable hotspots for recombination may be both among individuals (or populations) and over evolutionary timescales. Previous studies have suggested that locations of recombination hotspots are not conserved between humans and chimpanzees. We made use of the data sets from recent resequencing projects and applied a Bayesian method for identifying hotspots and estimating recombination rates. We also reanalyzed SNP data sets for regions with known hotspots in humans using samples from the human and chimpanzee. The Bayes factors (BF) of shared recombination hotspots between human and chimpanzee across regions were obtained. Based on the analysis of the aligned regions of human chromosome 21, locations where the two species show evidence of shared recombination hotspots (with high BFs) were identified. Interestingly, previous comparative studies of human and chimpanzee that focused on the known human recombination hotspots within the β-globin and HLA regions did not find overlapping of hotspots. Our results show high BFs of shared hotspots at locations within both regions, and the estimated locations of shared hotspots overlap with the locations of human recombination hotspots obtained from sperm-typing studies. PMID:25261696

Bayesian inference of shared recombination hotspots between humans and chimpanzees.

PubMed

Wang, Ying; Rannala, Bruce

2014-12-01

Recombination generates variation and facilitates evolution. Recombination (or lack thereof) also contributes to human genetic disease. Methods for mapping genes influencing complex genetic diseases via association rely on linkage disequilibrium (LD) in human populations, which is influenced by rates of recombination across the genome. Comparative population genomic analyses of recombination using related primate species can identify factors influencing rates of recombination in humans. Such studies can indicate how variable hotspots for recombination may be both among individuals (or populations) and over evolutionary timescales. Previous studies have suggested that locations of recombination hotspots are not conserved between humans and chimpanzees. We made use of the data sets from recent resequencing projects and applied a Bayesian method for identifying hotspots and estimating recombination rates. We also reanalyzed SNP data sets for regions with known hotspots in humans using samples from the human and chimpanzee. The Bayes factors (BF) of shared recombination hotspots between human and chimpanzee across regions were obtained. Based on the analysis of the aligned regions of human chromosome 21, locations where the two species show evidence of shared recombination hotspots (with high BFs) were identified. Interestingly, previous comparative studies of human and chimpanzee that focused on the known human recombination hotspots within the β-globin and HLA regions did not find overlapping of hotspots. Our results show high BFs of shared hotspots at locations within both regions, and the estimated locations of shared hotspots overlap with the locations of human recombination hotspots obtained from sperm-typing studies. Copyright © 2014 by the Genetics Society of America.

Western US volcanism due to intruding oceanic mantle driven by ancient Farallon slabs

NASA Astrophysics Data System (ADS)

Zhou, Quan; Liu, Lijun; Hu, Jiashun

2018-01-01

The origin of late Cenozoic intraplate volcanism over the western United States is debated. One important reason is the lack of a clear understanding of the mantle dynamics during this volcanic history. Here we reconstruct the mantle thermal states beneath North America since 20 million years ago using a hybrid inverse geodynamic model with data assimilation. The model simultaneously satisfies the past subduction kinematics, present mantle tomographic image and the volcanic history. We find that volcanism in both the Yellowstone volcanic province and the Basin and Range province corresponds to a similar eastward-intruding mantle derived from beneath the Pacific Ocean and driven mostly by the sinking Farallon slab below the central-eastern United States. The hot mantle that forms the Columbia River flood basalt and subsequent Yellowstone-Newberry hotspot tracks first enters the western United States through tears within the Juan de Fuca slab. Subsequent coexistence of the westward asthenospheric flow above the retreating Juan de Fuca slab and eastward-propagating mantle beyond the back-arc region reproduces the bifurcating hotspot chains. A similar but weaker heat source intrudes below the Basin and Range around the southern edge of the slab, and can explain the diffuse basaltic volcanism in this region. According to our models, the putative Yellowstone plume contributes little to the formation of the Yellowstone volcanic province.

Monitoring changes in Greater Yellowstone Lake water quality following the 1988 wildfires

NASA Technical Reports Server (NTRS)

Lathrop, Richard G., Jr.; Vande Castle, John D.; Brass, James A.

1994-01-01

The fires that burned the Greater Yellowstone Area (GYA) during the summer of 1988 were the largest ever recorded for the region. Wildfire can have profound indirect effects on associated aquatic ecosystems by increased nutrient loading, sediment, erosion, and runoff. Satellite remote sensing and water quality sampling were used to compare pre- versus post-fire conditions in the GYA's large oliotrophic (high transparency, low productivity) lakes. Inputs of suspended sediment to Jackson Lake appear to have increased. Yellowstone Lake has not shown any discernable shift in water quality. The insights gained separately from the Landsat Thematic and NOAA Advanced Very High Resolution Radiometer (AVHRR) remote sensing systems, along with conventional in-situ sampling, can be combined into a useful water quality monitoring tool.

DNA Sequence-Mediated, Evolutionarily Rapid Redistribution of Meiotic Recombination Hotspots

PubMed Central

Wahls, Wayne P.; Davidson, Mari K.

2011-01-01

Hotspots regulate the position and frequency of Spo11 (Rec12)-initiated meiotic recombination, but paradoxically they are suicidal and are somehow resurrected elsewhere in the genome. After the DNA sequence-dependent activation of hotspots was discovered in fission yeast, nearly two decades elapsed before the key realizations that (A) DNA site-dependent regulation is broadly conserved and (B) individual eukaryotes have multiple different DNA sequence motifs that activate hotspots. From our perspective, such findings provide a conceptually straightforward solution to the hotspot paradox and can explain other, seemingly complex features of meiotic recombination. We describe how a small number of single-base-pair substitutions can generate hotspots de novo and dramatically alter their distribution in the genome. This model also shows how equilibrium rate kinetics could maintain the presence of hotspots over evolutionary timescales, without strong selective pressures invoked previously, and explains why hotspots localize preferentially to intergenic regions and introns. The model is robust enough to account for all hotspots of humans and chimpanzees repositioned since their divergence from the latest common ancestor. PMID:22084420

Imbalance aware lithography hotspot detection: a deep learning approach

NASA Astrophysics Data System (ADS)

Yang, Haoyu; Luo, Luyang; Su, Jing; Lin, Chenxi; Yu, Bei

2017-03-01

With the advancement of VLSI technology nodes, light diffraction caused lithographic hotspots have become a serious problem affecting manufacture yield. Lithography hotspot detection at the post-OPC stage is imperative to check potential circuit failures when transferring designed patterns onto silicon wafers. Although conventional lithography hotspot detection methods, such as machine learning, have gained satisfactory performance, with extreme scaling of transistor feature size and more and more complicated layout patterns, conventional methodologies may suffer from performance degradation. For example, manual or ad hoc feature extraction in a machine learning framework may lose important information when predicting potential errors in ultra-large-scale integrated circuit masks. In this paper, we present a deep convolutional neural network (CNN) targeting representative feature learning in lithography hotspot detection. We carefully analyze impact and effectiveness of different CNN hyper-parameters, through which a hotspot-detection-oriented neural network model is established. Because hotspot patterns are always minorities in VLSI mask design, the training data set is highly imbalanced. In this situation, a neural network is no longer reliable, because a trained model with high classification accuracy may still suffer from high false negative results (missing hotspots), which is fatal in hotspot detection problems. To address the imbalance problem, we further apply minority upsampling and random-mirror flipping before training the network. Experimental results show that our proposed neural network model achieves highly comparable or better performance on the ICCAD 2012 contest benchmark compared to state-of-the-art hotspot detectors based on deep or representative machine leaning.

A Western Pacific Hotspot?

NASA Astrophysics Data System (ADS)

MacPherson, C. G.; Hall, R.

2002-12-01

The petrology of volcanic rocks from the St. Andrew Strait and helium isotope ratios of backarc lavas from the Manus Basin have been used to propose the existence of an active hotspot beneath the eastern Bismarck Sea [1,2]. The possible influence of this hotspot can be assessed by mapping its present location onto a plate tectonic reconstruction of the western Pacific [3,4]. During the Middle Eocene the nascent Izu-Bonin-Mariana (IBM) arc lay above the hotspot. The volume of magma emplaced at the IBM arc at that time substantially exceeds the average magma production rate for mature island arcs. Furthermore, the ultramafic (boninitic) character of much of this magmatism requires elevated temperatures in the mantle. The geochemistry of contemporaneous magmatism in the backarc resembles melts usually found at ocean islands and much of the backarc region experienced significant uplift at that time. All of these features can be explained by the influx of hot, buoyant, chemically distinct mantle beneath the IBM and its hinterland. The plates lying above the hotspot during the later Eocene were subsequently subducted, but plate reconstruction suggests that during the Oligo-Miocene it was crossed by parts of the Caroline Plate where the Euripik Rise is found. This is an aseismic rise that possesses the geophysical characteristics of thickened oceanic crust formed by excess, basaltic magmatism and is the type of structure that would result from the passage of relatively young oceanic lithosphere over a mantle hotspot. Plate reconstruction for the western Pacific predicts a hotspot trail that is consistent with the Middle Eocene and Oligo-Miocene geology of the IBM and Caroline Plates, respectively. Parts of the trail have been disrupted by subsequent sea-floor spreading or lost through subduction but the remaining vestiges are consistent with the action of a thermal anomaly throughout much of the Cenozoic. More speculatively, the difference in buoyancy between the IBM

Epigenetic functions enriched in transcription factors binding to mouse recombination hotspots.

PubMed

Wu, Min; Kwoh, Chee-Keong; Przytycka, Teresa M; Li, Jing; Zheng, Jie

2012-06-21

The regulatory mechanism of recombination is a fundamental problem in genomics, with wide applications in genome-wide association studies, birth-defect diseases, molecular evolution, cancer research, etc. In mammalian genomes, recombination events cluster into short genomic regions called "recombination hotspots". Recently, a 13-mer motif enriched in hotspots is identified as a candidate cis-regulatory element of human recombination hotspots; moreover, a zinc finger protein, PRDM9, binds to this motif and is associated with variation of recombination phenotype in human and mouse genomes, thus is a trans-acting regulator of recombination hotspots. However, this pair of cis and trans-regulators covers only a fraction of hotspots, thus other regulators of recombination hotspots remain to be discovered. In this paper, we propose an approach to predicting additional trans-regulators from DNA-binding proteins by comparing their enrichment of binding sites in hotspots. Applying this approach on newly mapped mouse hotspots genome-wide, we confirmed that PRDM9 is a major trans-regulator of hotspots. In addition, a list of top candidate trans-regulators of mouse hotspots is reported. Using GO analysis we observed that the top genes are enriched with function of histone modification, highlighting the epigenetic regulatory mechanisms of recombination hotspots.

Epigenetic functions enriched in transcription factors binding to mouse recombination hotspots

PubMed Central

2012-01-01

The regulatory mechanism of recombination is a fundamental problem in genomics, with wide applications in genome-wide association studies, birth-defect diseases, molecular evolution, cancer research, etc. In mammalian genomes, recombination events cluster into short genomic regions called "recombination hotspots". Recently, a 13-mer motif enriched in hotspots is identified as a candidate cis-regulatory element of human recombination hotspots; moreover, a zinc finger protein, PRDM9, binds to this motif and is associated with variation of recombination phenotype in human and mouse genomes, thus is a trans-acting regulator of recombination hotspots. However, this pair of cis and trans-regulators covers only a fraction of hotspots, thus other regulators of recombination hotspots remain to be discovered. In this paper, we propose an approach to predicting additional trans-regulators from DNA-binding proteins by comparing their enrichment of binding sites in hotspots. Applying this approach on newly mapped mouse hotspots genome-wide, we confirmed that PRDM9 is a major trans-regulator of hotspots. In addition, a list of top candidate trans-regulators of mouse hotspots is reported. Using GO analysis we observed that the top genes are enriched with function of histone modification, highlighting the epigenetic regulatory mechanisms of recombination hotspots. PMID:22759569

NIMS Observation of Hotspots on Io

NASA Technical Reports Server (NTRS)

1996-01-01

Io has been imaged by the Near Infrared Mapping Spectrometer (NIMS) on Galileo. The image on the right shows for the first time the distribution of volcanic hotspots on the surface of Io, as seen by NIMS. Three of these hotspots are new discoveries, only detectable with the NIMS instrument. This image was taken during the G1 encounter on June 29 1996. The image on the left shows the same view of Io as seen by the Voyager spacecraft in 1979. At least one dozen hotspots have been identified from this NIMS image. Most of the hotspot locations can be matched with volcanic features on the surface of Io, including the vent area of the active Prometheus plume.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

Grizzly bear use of army cutworm moths in the Yellowstone Ecosystem

USGS Publications Warehouse

French, Steven P.; French, Marilynn G.; Knight, Richard R.

1994-01-01

The ecology of alpine aggregations of army cutworm moths (Euxoa auxiliaris) and the feeding behavior of grizzly bears (Ursus arctos horribilis) at these areas were studied in the Yellowstone ecosystem from 1988 to 1991. Army cutworm moths migrate to mountain regions each summer to feed at night on the nectar of alpine and subalpine flowers, and during the day they seek shelter under various rock formations. Grizzly bears were observed feeding almost exclusively on moths up to 3 months each summer at the 10 moth-aggregation areas we identified. Fifty-one different grizzly bears were observed feeding at 4 of these areas during a single day in August 1991. Army cutworm moths are a preferred source of nutrition for many grizzly bears in the Yellowstone ecosystem and represent a high quality food that is available during hyperphagia.

New evidence for the Hawaiian hotspot plume motion since the Eocene

NASA Astrophysics Data System (ADS)

Parés, Josep M.; Moore, Ted C.

2005-09-01

A thick mound of fossiliferous sediments, reflecting high biogenic productivity at the Equator can be used to determine latitudinal motion of the Pacific lithospheric plate. Plate motion estimates based on the latitudinal movement of Equatorial facies are independent of paleomagnetic data and hotspot tracks and thus permit further testing of kinematic models. We have determined the northward motion of the Pacific Plate for the last 53 Myr based on the position of the paleoequator as shown by Equatorial sediment facies. Between 26 and 69 DSDP and ODP Sites sample the past 53 Myr in the tropical Pacific. Based on the mapped patterns of accumulation rates in these sites, we were able not only to determine the position of the paleoequator but also to estimate the Equatorial great circle and hence the relative position of the spin axis since the early Eocene. The northward motion of the Pacific Plate inferred from the change in latitude of dated Hawaiian Chain seamounts relative to the Hawaiian hotspot is consistently higher than that deduced from the analyses of Equatorial sediment facies. Such a difference results from a latitudinal shift of the Hawaiian hotspot during the last 53 Myr. All together, our observations and recent paleomagnetic results from the Detroit, Nintoku and Koko seamounts [J.A. Tarduno, R.A. Duncan, D.W. Scholl, R.D. Cottrell, B., Steinberger, T. Thordarson, B.C. Kerr, C.R. Neal, F.A. Frey, M. Torii, M., C. Carvallo. The Emperor Seamounts: Southward motion of the Hawaiian hotspot plume in Earth's mantle. Science 301 (2003) 1064-1069.] [1] are consistent with a progressive southward motion of the Hawaiian mantle plume since the Late Cretaceous. Our results suggest that the Hawaiian hotspot moved at ˜32 mm/yr to the SE during the past 43 million years and that the Pacific Plate moved ˜12° northward since 53 Ma at an average rate of 25 mm/yr.

Trumpeter swan food habitats in the greater Yellowstone ecosystem

Treesearch

John R. Squires; Stanley H. Anderson

1995-01-01

We documented the winter, spring and summer food habits of trumpeter swans (Cygnus buccinator) in the greater Yellowstone area (the intersection of Idaho, Montana and Wyoming) and studied the diet preference of nesting swans. Although 23 foods were detected in trumpeter swan diets during the winter, spring and summer, only 8 contributed at least 3% to the diet...

Hotspots and the conservation of evolutionary history

PubMed Central

Sechrest, Wes; Brooks, Thomas M.; da Fonseca, Gustavo A. B.; Konstant, William R.; Mittermeier, Russell A.; Purvis, Andy; Rylands, Anthony B.; Gittleman, John L.

2002-01-01

Species diversity is unevenly distributed across the globe, with terrestrial diversity concentrated in a few restricted biodiversity hotspots. These areas are associated with high losses of primary vegetation and increased human population density, resulting in growing numbers of threatened species. We show that conservation of these hotspots is critical because they harbor even greater amounts of evolutionary history than expected by species numbers alone. We used supertrees for carnivores and primates to estimate that nearly 70% of the total amount of evolutionary history represented in these groups is found in 25 biodiversity hotspots. PMID:11854502

Exterior sound level measurements of over-snow vehicles at Yellowstone National Park.

DOT National Transportation Integrated Search

2008-09-30

Sounds associated with oversnow vehicles, such as snowmobiles and snowcoaches, are an : important management concern at Yellowstone and Grand Teton National Parks. The John A. : Volpe National Transportation Systems Centers Environmental Measureme...

Discovery of hotspots on Io using disk-resolved infrared imaging

NASA Technical Reports Server (NTRS)

Spencer, J. R.; Shure, M. A.; Ressler, M. E.; Sinton, W. M.; Goguen, J. D.

1990-01-01

First results are presented using two new techniques for ground-based observation of Io's hotspots. An IR array camera was used to obtain direct IR images of Io with resolution better than 0.5 arcsec, so that more than one hotspot is seen on Io in Jupiter eclipse. The camera was also used to make the first observations of the Jupiter occultation of the hotspots. These new techniques have revealed and located at least three hotspots and will now permit routine ground-based monitoring of the locations, temperatures, and sizes of multiple hotspots on Io.

What makes labour and birth traumatic? A survey of intrapartum 'hotspots'.

PubMed

Harris, Rachel; Ayers, Susan

2012-01-01

Evidence suggests between 1% and 6% of women develop post-traumatic stress disorder (PTSD) after childbirth. 'Hotspots' are moments of extreme distress during traumatising events that are implicated in symptoms of PTSD. This cross-sectional internet survey of hotspots examined (1) the content of intrapartum hotspots and (2) whether particular events, cognitions or emotions during hotspots are related to PTSD. Women (N = 675) who experienced a difficult or traumatic birth completed a questionnaire composed of a validated measure of PTSD, questions concerning the existence of hotspots, and a newly developed measure of emotions and cognitions during hotspots. The majority of women (67.4%) reported at least one hotspot during birth and 52.9% had re-experiencing symptoms of these hotspots. Women were more likely to have PTSD if hotspots involved fear and lack of control (odds ratio (OR) 1.30, 95% CI 1.17-1.43) or intrapartum dissociation (OR 1.12, 95% CI 1.05-1.19). Risk of PTSD was higher if hotspots concerned interpersonal difficulties (OR 4.34, 95% CI 2.15-8.77) or obstetric complications (OR 3.35, 95% CI 1.64-6.87) compared to complications with the baby.

Inquiry-based Science Activities Using The Infrared Zoo and Infrared Yellowstone Resources at Cool Cosmos

NASA Astrophysics Data System (ADS)

Daou, D.; Gauthier, A.

2003-12-01

Inquiry-based activities that utilize the Cool Cosmos image galleries have been designed and developed by K12 teachers enrolled in The Invisible Universe Online for Teachers course. The exploration activities integrate the Our Infrared World Gallery (http://coolcosmos.ipac.caltech.edu/image_galleries/our_ir_world_gallery.html) with either the Infrared Zoo gallery (http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/index.html) or the Infrared Yellowstone image http://coolcosmos.ipac.caltech.edu/image_galleries/ir_yellowstone/index.html) and video (http://coolcosmos.ipac.caltech.edu/videos/ir_yellowstone/index.html) galleries. Complete instructor guides have been developed for the activities and will be presented by the authors in poster and CD form. Although the activities are written for middle and highschool learners, they can easily be adapted for college audiences. The Our Infrared World Gallery exploration helps learners think critically about visible light and infrared light as they compare sets of images (IR and visible light) of known objects. For example: by taking a regular photograph of a running faucet, can you tell if it is running hot or cold water? What new information does the IR image give you? The Infrared Zoo activities encourage learners to investigate the differences between warm and cold blooded animals by comparing sets of IR and visible images. In one activity, learners take on the role of a pit viper seeking prey in various desert and woodland settings. The main activities are extended into the real world by discussing and researching industrial, medical, and societal applications of infrared technologies. The Infrared Yellowstone lessons give learners a unique perspective on Yellowstone National Park and it's spectacular geologic and geothermal features. Infrared video technology is highlighted as learners make detailed observations about the visible and infrared views of the natural phenomena. The "Cool Cosmos" EPO activities are

Leg 197 synthesis: Southward motion and geochemical variability of the Hawaiian hotspot

USGS Publications Warehouse

Duncan, Robert A.; Tarduno, John A.; Scholl, David W.; Duncan, Robert A.; Tarduno, John A.; Davies, Thomas A.; Scholl, David W.

2006-01-01

The bend in the Hawaiian-Emperor volcanic chain is an often-cited example of a change in plate motion with respect to a stationary hotspot. Growing evidence, however, suggests that the bend might instead record variable drift of the Hawaiian hotspot within a convecting mantle. Paleomagnetic and radiometric age data from samples recovered during Ocean Drilling Program (ODP) Leg 197 define an age-progressive paleolatitude history, indicating that the Emperor Seamounts volcanic trend was formed principally by rapid (4–5 cm/yr) southward motion of the Hawaiian hotspot during Late Cretaceous to early Tertiary time (81–47 Ma). Paleointensity data derived from Leg 197 suggest an inverse relationship between field strength and reversal frequency, consistent with an active lower mantle that controls the efficiency of the geodynamo. Petrochemical data and observations of volcanic products (lava flows and volcaniclastic sediments) from Detroit, Nintoku, and Koko Seamounts provide records of the evolution of these volcanic systems for comparison with recent activity in the Hawaiian Islands. We find that the Emperor Seamounts formed from similar mantle sources for melting (plume components and lithosphere) and in much the same stages of volcanic activity and time span as the Hawaiian volcanoes. Changes in major and trace element and Sr isotopic compositions of shield lavas along the lineament can be related to variations in thickness of the lithosphere overlying the hotspot that control the depth and extent of partial melting. Other geochemical tracers, such as He, Pb, and Hf isotopic compositions, indicate persistent contributions to melting from the plume throughout the volcanic chain.

General Practice Clinical Data Help Identify Dementia Hotspots: A Novel Geospatial Analysis Approach.

PubMed

Bagheri, Nasser; Wangdi, Kinley; Cherbuin, Nicolas; Anstey, Kaarin J

2018-01-01

We have a poor understanding of whether dementia clusters geographically, how this occurs, and how dementia may relate to socio-demographic factors. To shed light on these important questions, this study aimed to compute a dementia risk score for individuals to assess spatial variation of dementia risk, identify significant clusters (hotspots), and explore their association with socioeconomic status. We used clinical records from 16 general practices (468 Statistical Area level 1 s, N = 14,746) from the city of west Adelaide, Australia for the duration of 1 January 2012 to 31 December 2014. Dementia risk was estimated using The Australian National University-Alzheimer's Disease Risk Index. Hotspot analyses were applied to examine potential clusters in dementia risk at small area level. Significant hotspots were observed in eastern and southern areas while coldspots were observed in the western area within the study perimeter. Additionally, significant hotspots were observed in low socio-economic communities. We found dementia risk scores increased with age, sex (female), high cholesterol, no physical activity, living alone (widow, divorced, separated, or never married), and co-morbidities such as diabetes and depression. Similarly, smoking was associated with a lower dementia risk score. The identification of dementia risk clusters may provide insight into possible geographical variations in risk factors for dementia and quantify these risks at the community level. As such, this research may enable policy makers to tailor early prevention strategies to the correct individuals within their precise locations.

Holocene Beaver Effects on Small Streams in Yellowstone and Implications for Stream Restoration

NASA Astrophysics Data System (ADS)

Persico, L. P.; Meyer, G.

2005-12-01

It has been asserted that beaver ( Castor canadensis) damming has sustained long-term aggradation and exerted a dominant control on the morphology of small streams over much of North America. However, data on the temporal and spatial dimensions of beaver influence are extremely limited. Using beaver pond deposits and berms (abandoned dams), we document geomorphic effects of beavers on first- to fourth-order streams in semiarid-subhumid northern Yellowstone National Park, USA. Beavers were ubiquitous in the early 20th century, but are currently rare. Some formerly dammed streams have become ephemeral in recent droughts, suggesting that climate may be a significant factor controlling beaver occupation. Radiocarbon dating of wood preserved in pond deposits and berms shows notable periods of beaver activity 3655-3855, 1555-955, and 455-150 cal yr BP, but a distinct lack of activity 950-700 cal yr BP during the Medieval Climatic Anomaly, a time of severe multidecadal droughts in Yellowstone and the western USA. The spatial scale over which beavers incurred significant aggradation is controlled largely by geomorphic settings conducive to damming. Low-gradient (0.07 to 0.001) reaches with contributing areas of 4 to 70 km2 are typical for dam sites. Reaches with downstream valley constrictions are most susceptible to aggradation. Only a small fraction of the total stream length in the study area has experienced significant aggradation attributable to beaver damming, as shown by accumulations of sand and finer sediment of up to 3 m, thicker than typical overbank sediments. These sediments locally contain evidence of ponding in laminations, gleying, and high organic content. Many reaches show no evidence of any net aggradation since deglaciation. Many beaver-aggraded reaches are now incised, typically 1.5-2 m and up to 3 m. Some reaches have early Holocene (ca. 10150-8000 cal yr BP) terraces with treads ~2 m above current bankfull level, underlain by both gravelly and fine

Density-dependent intraspecific aggression regulates survival in northern Yellowstone wolves (Canis lupus).

PubMed

Cubaynes, Sarah; MacNulty, Daniel R; Stahler, Daniel R; Quimby, Kira A; Smith, Douglas W; Coulson, Tim

2014-11-01

Understanding the population dynamics of top-predators is essential to assess their impact on ecosystems and to guide their management. Key to this understanding is identifying the mechanisms regulating vital rates. Determining the influence of density on survival is necessary to understand the extent to which human-caused mortality is compensatory or additive. In wolves (Canis lupus), empirical evidence for density-dependent survival is lacking. Dispersal is considered the principal way in which wolves adjust their numbers to prey supply or compensate for human exploitation. However, studies to date have primarily focused on exploited wolf populations, in which density-dependent mechanisms are likely weak due to artificially low wolf densities. Using 13 years of data on 280 collared wolves in Yellowstone National Park, we assessed the effect of wolf density, prey abundance and population structure, as well as winter severity, on age-specific survival in two areas (prey-rich vs. prey-poor) of the national park. We further analysed cause-specific mortality and explored the factors driving intraspecific aggression in the prey-rich northern area of the park. Overall, survival rates decreased during the study. In northern Yellowstone, density dependence regulated adult survival through an increase in intraspecific aggression, independent of prey availability. In the interior of the park, adult survival was less variable and density-independent, despite reduced prey availability. There was no effect of prey population structure in northern Yellowstone, or of winter severity in either area. Survival was similar among yearlings and adults, but lower for adults older than 6 years. Our results indicate that density-dependent intraspecific aggression is a major driver of adult wolf survival in northern Yellowstone, suggesting intrinsic density-dependent mechanisms have the potential to regulate wolf populations at high ungulate densities. When low prey availability or high

Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots.

PubMed

Baker, Christopher L; Petkova, Pavlina; Walker, Michael; Flachs, Petr; Mihola, Ondrej; Trachtulec, Zdenek; Petkov, Petko M; Paigen, Kenneth

2015-09-01

Genetic recombination during meiosis functions to increase genetic diversity, promotes elimination of deleterious alleles, and helps assure proper segregation of chromatids. Mammalian recombination events are concentrated at specialized sites, termed hotspots, whose locations are determined by PRDM9, a zinc finger DNA-binding histone methyltransferase. Prdm9 is highly polymorphic with most alleles activating their own set of hotspots. In populations exhibiting high frequencies of heterozygosity, questions remain about the influences different alleles have in heterozygous individuals where the two variant forms of PRDM9 typically do not activate equivalent populations of hotspots. We now find that, in addition to activating its own hotspots, the presence of one Prdm9 allele can modify the activity of hotspots activated by the other allele. PRDM9 function is also dosage sensitive; Prdm9+/- heterozygous null mice have reduced numbers and less active hotspots and increased numbers of aberrant germ cells. In mice carrying two Prdm9 alleles, there is allelic competition; the stronger Prdm9 allele can partially or entirely suppress chromatin modification and recombination at hotspots of the weaker allele. In cell cultures, PRDM9 protein variants form functional heteromeric complexes which can bind hotspots sequences. When a heteromeric complex binds at a hotspot of one PRDM9 variant, the other PRDM9 variant, which would otherwise not bind, can still methylate hotspot nucleosomes. We propose that in heterozygous individuals the underlying molecular mechanism of allelic suppression results from formation of PRDM9 heteromers, where the DNA binding activity of one protein variant dominantly directs recombination initiation towards its own hotspots, effectively titrating down recombination by the other protein variant. In natural populations with many heterozygous individuals, allelic competition will influence the recombination landscape.

Characterization and Prediction of Protein Phosphorylation Hotspots in Arabidopsis thaliana.

PubMed

Christian, Jan-Ole; Braginets, Rostyslav; Schulze, Waltraud X; Walther, Dirk

2012-01-01

The regulation of protein function by modulating the surface charge status via sequence-locally enriched phosphorylation sites (P-sites) in so called phosphorylation "hotspots" has gained increased attention in recent years. We set out to identify P-hotspots in the model plant Arabidopsis thaliana. We analyzed the spacing of experimentally detected P-sites within peptide-covered regions along Arabidopsis protein sequences as available from the PhosPhAt database. Confirming earlier reports (Schweiger and Linial, 2010), we found that, indeed, P-sites tend to cluster and that distributions between serine and threonine P-sites to their respected closest next P-site differ significantly from those for tyrosine P-sites. The ability to predict P-hotspots by applying available computational P-site prediction programs that focus on identifying single P-sites was observed to be severely compromised by the inevitable interference of nearby P-sites. We devised a new approach, named HotSPotter, for the prediction of phosphorylation hotspots. HotSPotter is based primarily on local amino acid compositional preferences rather than sequence position-specific motifs and uses support vector machines as the underlying classification engine. HotSPotter correctly identified experimentally determined phosphorylation hotspots in A. thaliana with high accuracy. Applied to the Arabidopsis proteome, HotSPotter-predicted 13,677 candidate P-hotspots in 9,599 proteins corresponding to 7,847 unique genes. Hotspot containing proteins are involved predominantly in signaling processes confirming the surmised modulating role of hotspots in signaling and interaction events. Our study provides new bioinformatics means to identify phosphorylation hotspots and lays the basis for further investigating novel candidate P-hotspots. All phosphorylation hotspot annotations and predictions have been made available as part of the PhosPhAt database at http://phosphat.mpimp-golm.mpg.de.

Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots

PubMed Central

Baker, Christopher L.; Petkova, Pavlina; Walker, Michael; Flachs, Petr; Mihola, Ondrej; Trachtulec, Zdenek; Petkov, Petko M.; Paigen, Kenneth

2015-01-01

Genetic recombination during meiosis functions to increase genetic diversity, promotes elimination of deleterious alleles, and helps assure proper segregation of chromatids. Mammalian recombination events are concentrated at specialized sites, termed hotspots, whose locations are determined by PRDM9, a zinc finger DNA-binding histone methyltransferase. Prdm9 is highly polymorphic with most alleles activating their own set of hotspots. In populations exhibiting high frequencies of heterozygosity, questions remain about the influences different alleles have in heterozygous individuals where the two variant forms of PRDM9 typically do not activate equivalent populations of hotspots. We now find that, in addition to activating its own hotspots, the presence of one Prdm9 allele can modify the activity of hotspots activated by the other allele. PRDM9 function is also dosage sensitive; Prdm9 +/- heterozygous null mice have reduced numbers and less active hotspots and increased numbers of aberrant germ cells. In mice carrying two Prdm9 alleles, there is allelic competition; the stronger Prdm9 allele can partially or entirely suppress chromatin modification and recombination at hotspots of the weaker allele. In cell cultures, PRDM9 protein variants form functional heteromeric complexes which can bind hotspots sequences. When a heteromeric complex binds at a hotspot of one PRDM9 variant, the other PRDM9 variant, which would otherwise not bind, can still methylate hotspot nucleosomes. We propose that in heterozygous individuals the underlying molecular mechanism of allelic suppression results from formation of PRDM9 heteromers, where the DNA binding activity of one protein variant dominantly directs recombination initiation towards its own hotspots, effectively titrating down recombination by the other protein variant. In natural populations with many heterozygous individuals, allelic competition will influence the recombination landscape. PMID:26368021

Algal and Water-Quality Data for the Yellowstone River and Tributaries, Montana and Wyoming, 1999-2000

USGS Publications Warehouse

Peterson, David A.

2009-01-01

Streams of the Yellowstone River Basin in Montana and Wyoming were sampled as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Algal communities were sampled in 1999 in conjunction with other ecological sampling and in 2000 during synoptic sampling. Water-quality measurements related to the algal sampling included light attenuation and dissolved-oxygen concentrations. Sites were sampled on the main-stem Yellowstone River, major tributaries such as the Clarks Fork Yellowstone River and the Bighorn River, and selected minor tributaries. Some of the data collected, such as the phytoplankton chlorophyll-a data, were referenced or summarized in previous U.S. Geological Survey reports but were not previously published in tabular form, and therefore are presented in this report, prepared in cooperation with the Montana Department of Environmental Quality. Data presented in this report include chlorophyll-a concentrations in phytoplankton and periphyton samples, as well as light attenuation and dissolved-oxygen production data from 1999-2000.

Thermomechanical Modeling of the Formation of a Multilevel, Crustal-Scale Magmatic System by the Yellowstone Plume

NASA Astrophysics Data System (ADS)

Colón, D. P.; Bindeman, I. N.; Gerya, T. V.

2018-05-01

Geophysical imaging of the Yellowstone supervolcano shows a broad zone of partial melt interrupted by an amagmatic gap at depths of 15-20 km. We reproduce this structure through a series of regional-scale magmatic-thermomechanical forward models which assume that magmatic dikes stall at rheologic discontinuities in the crust. We find that basaltic magmas accumulate at the Moho and at the brittle-ductile transition, which naturally forms at depths of 5-10 km. This leads to the development of a 10- to 15-km thick midcrustal sill complex with a top at a depth of approximately 10 km, consistent with geophysical observations of the pre-Yellowstone hot spot track. We show a linear relationship between melting rates in the mantle and rhyolite eruption rates along the hot spot track. Finally, melt production rates from our models suggest that the Yellowstone plume is 175°C hotter than the surrounding mantle and that the thickness of the overlying lithosphere is 80 km.

Inorganic nitrogen availability after severe stand-replacing fire in the Greater Yellowstone ecosystem

PubMed Central

Turner, Monica G.; Smithwick, Erica A. H.; Metzger, Kristine L.; Tinker, Daniel B.; Romme, William H.

2007-01-01

Understanding ecosystem processes as they relate to wildfire and vegetation dynamics is of growing importance as fire frequency and extent increase throughout the western United States. However, the effects of severe, stand-replacing wildfires are poorly understood. We studied inorganic nitrogen pools and mineralization rates after stand-replacing wildfires in the Greater Yellowstone Ecosystem, Wyoming. After fires that burned in summer 2000, soil ammonium concentration peaked in 2001 (33 mg NH4-N· kgsoil−1); soil nitrate increased subsequently (2.7 mg NO3-N·kgsoil−1 in 2003) but was still low. However, annual net ammonification rates were largely negative from 2001 to 2004, indicating ammonium depletion. Thus, although net nitrification rates were positive, annual net nitrogen mineralization (net ammonification plus net nitrification) remained low. Aboveground net primary production (ANPP) increased from 0.25 to 1.6 Mg·ha−1·yr−1 from 2001 to 2004, but variation in ANPP among stands was not related to net nitrogen mineralization rates. Across a broader temporal gradient (stand age zero to >250 yr), negative rates of net annual ammonification were especially pronounced in the first postfire year. Laboratory incubations using 15N isotope pool dilution revealed that gross production of ammonium was reduced and ammonium consumption greatly exceeded gross production during the initial postfire years. Our results suggest a microbial nitrogen sink for several years after severe, stand-replacing fire, confirming earlier hypotheses about postdisturbance succession and nutrient cycling in cold, fire-dominated coniferous forests. Postfire forests in Yellowstone seem to be highly conservative for nitrogen, and microbial immobilization of ammonium plays a key role during early succession. PMID:17360349

Life history characteristics and vital rates of Yellowstone Cutthroat Trout in two headwater basins

USGS Publications Warehouse

Uthe, Patrick; Al-Chokhachy, Robert K.; Zale, Alexander V.; Shepard, Bradley B.; McMahon, Thomas E.; Stephens, Tracy

2016-01-01

The Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri is native to the Rocky Mountains and has declined in abundance and distribution as a result of habitat degradation and introduced salmonid species. Many of its remaining strongholds are in headwater basins with minimal human disturbances. Understanding the life histories, vital rates, and behaviors of Yellowstone Cutthroat Trout within headwater stream networks remains limited yet is critical for effective management and conservation. We estimated annual relative growth in length and weight, annual survival rates, and movement patterns of Yellowstone Cutthroat Trout from three tributaries of Spread Creek, Wyoming, and two tributaries of Shields River, Montana, from 2011 through 2013 using PIT tag antennas within a mark–recapture framework. Mean annual growth rates varied among tributaries and size-classes, but were slow compared with populations of Yellowstone Cutthroat Trout from large, low-elevation streams. Survival rates were relatively high compared with those of other Cutthroat Trout subspecies, but we found an inverse relationship between survival and size, a pattern contrary to what has been reported for Cutthroat Trout in large streams. Mean annual survival rates ranged from 0.32 (SE = 0.04) to 0.68 (SE = 0.05) in the Spread Creek basin and from 0.30 (SE = 0.07) to 0.69 (SE = 0.10) in the Shields River basin. Downstream movements from tributaries were substantial, with as much as 26.5% of a tagging cohort leaving over the course of the study. Integrating our growth, survival, and movement results demonstrates the importance of considering strategies to enhance headwater stream habitats and highlights the importance of connectivity with larger stream networks.

Beaver damming, fluvial geomorphology, and climate in Yellowstone National Park, Wyoming

NASA Astrophysics Data System (ADS)

Persico, L.; Meyer, G.

2008-12-01

Beaver habitation is an important component of many fluvial landscapes that can impact a variety of hydrologic, geomorphic, and ecologic processes. Beaver damming, via long term valley aggradation, is thought to be important to the postglacial geomorphic evolution of many smaller mountain stream networks in the western United States. Loss of beaver dams can also cause rapid channel incision. Although several studies have documented rapid short-term aggradation of channels behind single beaver dams, there is little actual data on the long-term cumulative effect of beaver damming. In Yellowstone''s Northern Range, field surveys and stratigraphic section along six streams in the Northern Range reveal net thickness of mostly <2 m and patchy distribution of Holocene beaver-pond deposits. We estimate that reaches with clear morphologic and stratigraphic evidence for beaver-related aggradation constitute about 19% of the total stream network length. Reaches with probable and possible beaver-related aggradation make up an additional 8% and 2% of the network, respectively. The remaining 71% of the network has no clear evidence for beaver-related aggradation. Thirty-nine radiocarbon ages on beaver-pond deposits in northern Yellowstone fall primarily within the last 4000 yr, but gaps in dated beaver occupation from 2200-1800 and 950-750 cal yr BP correspond with severe and persistent droughts that likely caused low to ephemeral discharges in smaller streams. In the last two decades, severe drought has also caused streams that were occupied by beaver in the 1920s to become ephemeral. Beaver have been largely absent from the Northern Range since the mid-20th century, probably due to multiple ecological and climatic factors. This loss of beaver is thought to have led to widespread degradation of stream and riparian habitat via channel incision. Although 20th-century beaver loss has caused significant channel incision at some former dam sites, downcutting elsewhere in northern

Fire growth maps for the 1988 Greater Yellowstone Area Fires

Treesearch

Richard C. Rothermel; Roberta A Hartford; Carolyn H. Chase

1994-01-01

Daily fire growth maps display the growth of the 1988 fires in the Greater Yellowstone Area. Information and data sources included daily infrared photography flights, satellite imagery, ground and aerial reconnaissance, command center intelligence, and the personal recollections of fire behavior observers. Fire position was digitized from topographic maps using GRASS...

Database for the Quaternary and Pliocene Yellowstone Plateau volcanic field of Wyoming, Idaho, and Montana (Database for Professional Paper 729-G)

USGS Publications Warehouse

Koch, Richard D.; Ramsey, David W.; Christiansen, Robert L.

2011-01-01

The superlative hot springs, geysers, and fumarole fields of Yellowstone National Park are vivid reminders of a recent volcanic past. Volcanism on an immense scale largely shaped the unique landscape of central and western Yellowstone Park, and intimately related tectonism and seismicity continue even now. Furthermore, the volcanism that gave rise to Yellowstone's hydrothermal displays was only part of a long history of late Cenozoic eruptions in southern and eastern Idaho, northwestern Wyoming, and southwestern Montana. The late Cenozoic volcanism of Yellowstone National Park, although long believed to have occurred in late Tertiary time, is now known to have been of latest Pliocene and Pleistocene age. The eruptions formed a complex plateau of voluminous rhyolitic ash-flow tuffs and lavas, but basaltic lavas too have erupted intermittently around the margins of the rhyolite plateau. Volcanism almost certainly will recur in the Yellowstone National Park region. This digital release contains all the information used to produce the geologic maps published as plates in U.S. Geological Survey Professional Paper 729-G (Christiansen, 2001). The main component of this digital release is a geologic map database prepared using geographic information systems (GIS) applications. This release also contains files to view or print the geologic maps and main report text from Professional Paper 729-G.

Thermally-Driven Mantle Plumes Reconcile Hot-spot Observations

NASA Astrophysics Data System (ADS)

Davies, D.; Davies, J.

2008-12-01

Hot-spots are anomalous regions of magmatism that cannot be directly associated with plate tectonic processes (e.g. Morgan, 1972). They are widely regarded as the surface expression of upwelling mantle plumes. Hot-spots exhibit variable life-spans, magmatic productivity and fixity (e.g. Ito and van Keken, 2007). This suggests that a wide-range of upwelling structures coexist within Earth's mantle, a view supported by geochemical and seismic evidence, but, thus far, not reproduced by numerical models. Here, results from a new, global, 3-D spherical, mantle convection model are presented, which better reconcile hot-spot observations, the key modification from previous models being increased convective vigor. Model upwellings show broad-ranging dynamics; some drift slowly, while others are more mobile, displaying variable life-spans, intensities and migration velocities. Such behavior is consistent with hot-spot observations, indicating that the mantle must be simulated at the correct vigor and in the appropriate geometry to reproduce Earth-like dynamics. Thermally-driven mantle plumes can explain the principal features of hot-spot volcanism on Earth.

A hotspot model for leaf canopies

NASA Technical Reports Server (NTRS)

Jupp, David L. B.; Strahler, Alan H.

1991-01-01

The hotspot effect, which provides important information about canopy structure, is modeled using general principles of environmental physics as driven by parameters of interest in remote sensing, such as leaf size, leaf shape, leaf area index, and leaf angle distribution. Specific examples are derived for canopies of horizontal leaves. The hotspot effect is implemented within the framework of the model developed by Suits (1972) for a canopy of leaves to illustrate what might occur in an agricultural crop. Because the hotspot effect arises from very basic geometrical principles and is scale-free, it occurs similarly in woodlands, forests, crops, rough soil surfaces, and clouds. The scaling principles advanced are also significant factors in the production of image spatial and angular variance and covariance which can be used to assess land cover structure through remote sensing.

Hotspots on Io During the Ganymede 2 Encounter

NASA Technical Reports Server (NTRS)

1996-01-01

The Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft imaged Io at high spectral resolution at a range of 439,000 km (275,000 miles) during the G2 encounter on 6 September 1996. This image shows, on the right, Io as seen by NIMS, centered on 150 W longitude. The image on the left shows the same view point from Voyager data (from the encounters in 1979 and 1980). The NIMS image can be compared to the NIMS hotspot image from the G1 orbit (June 1996) to monitor changes on Io. The most dramatic feature of the G2 image is the hotspot at Malik Patera. Preliminary analysis of the data yields a temperature of at least 1000 K (727 C) for this hotspot, an increase of more than 300 K from the G1 encounter. In the overlap area of the G1 and G2 images all the hotspots seen during the G1 encounter are also seen in the G2 image. Other hotspots were seen, including one at the Pele plume origin site. This image is at the 4 micron band to best view the Malik hotspot. Most of the other hotspots are best seen at longer wavelengths. NIMS is continuing to observe Io to monitor volcanic activity throughout the Galileo mission.

The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

VP and VS structure of the Yellowstone hot spot from teleseismic tomography: Evidence for an upper mantle plume

USGS Publications Warehouse

Waite, Gregory P.; Smith, Robert B.; Allen, Richard M.

2006-01-01

The movement of the lithosphere over a stationary mantle magmatic source, often thought to be a mantle plume, explains key features of the 16 Ma Yellowstone–Snake River Plain volcanic system. However, the seismic signature of a Yellowstone plume has remained elusive because of the lack of adequate data. We employ new teleseismic P and S wave traveltime data to develop tomographic images of the Yellowstone hot spot upper mantle. The teleseismic data were recorded with two temporary seismograph arrays deployed in a 500 km by 600 km area centered on Yellowstone. Additional data from nearby regional seismic networks were incorporated into the data set. The VP and VS models reveal a strong low-velocity anomaly from ∼50 to 200 km directly beneath the Yellowstone caldera and eastern Snake River Plain, as has been imaged in previous studies. Peak anomalies are −2.3% for VP and −5.5% for VS. A weaker, anomaly with a velocity perturbation of up to −1.0% VP and −2.5% VS continues to at least 400 km depth. This anomaly dips 30° from vertical, west-northwest to a location beneath the northern Rocky Mountains. We interpret the low-velocity body as a plume of upwelling hot, and possibly wet rock, from the mantle transition zone that promotes small-scale convection in the upper ∼200 km of the mantle and long-lived volcanism. A high-velocity anomaly, 1.2%VP and 1.9% VS, is located at ∼100 to 250 km depth southeast of Yellowstone and may represent a downwelling of colder, denser mantle material.

Exploration and discovery in Yellowstone Lake: Results from high-resolution sonar imaging, seismic reflection profiling, and submersible studies

USGS Publications Warehouse

Morgan, L.A.; Shanks, Wayne C.; Lovalvo, D.A.; Johnson, S.Y.; Stephenson, W.J.; Pierce, K.L.; Harlan, S.S.; Finn, C.A.; Lee, G.; Webring, M.; Schulze, B.; Duhn, J.; Sweeney, R.; Balistrieri, L.

2003-01-01

Discoveries from multi-beam sonar mapping and seismic reflection surveys of the northern, central, and West Thumb basins of Yellowstone Lake provide new insight into the extent of post-collapse volcanism and active hydrothermal processes occurring in a large lake environment above a large magma chamber. Yellowstone Lake has an irregular bottom covered with dozens of features directly related to hydrothermal, tectonic, volcanic, and sedimentary processes. Detailed bathymetric, seismic reflection, and magnetic evidence reveals that rhyolitic lava flows underlie much of Yellowstone Lake and exert fundamental control on lake bathymetry and localization of hydrothermal activity. Many previously unknown features have been identified and include over 250 hydrothermal vents, several very large (>500 m diameter) hydrothermal explosion craters, many small hydrothermal vent craters (???1-200 m diameter), domed lacustrine sediments related to hydrothermal activity, elongate fissures cutting post-glacial sediments, siliceous hydrothermal spire structures, sublacustrine landslide deposits, submerged former shorelines, and a recently active graben. Sampling and observations with a submersible remotely operated vehicle confirm and extend our understanding of the identified features. Faults, fissures, hydrothermally inflated domal structures, hydrothermal explosion craters, and sublacustrine landslides constitute potentially significant geologic hazards. Toxic elements derived from hydrothermal processes also may significantly affect the Yellowstone ecosystem. Published by Elsevier Science B.V.

Modeling survival: application of the Andersen-Gill model to Yellowstone grizzly bears

USGS Publications Warehouse

Johnson, Christopher J.; Boyce, Mark S.; Schwartz, Charles C.; Haroldson, Mark A.

2004-01-01

 Wildlife ecologists often use the Kaplan-Meier procedure or Cox proportional hazards model to estimate survival rates, distributions, and magnitude of risk factors. The Andersen-Gill formulation (A-G) of the Cox proportional hazards model has seen limited application to mark-resight data but has a number of advantages, including the ability to accommodate left-censored data, time-varying covariates, multiple events, and discontinuous intervals of risks. We introduce the A-G model including structure of data, interpretation of results, and assessment of assumptions. We then apply the model to 22 years of radiotelemetry data for grizzly bears (Ursus arctos) of the Greater Yellowstone Grizzly Bear Recovery Zone in Montana, Idaho, and Wyoming, USA. We used Akaike's Information Criterion (AICc) and multi-model inference to assess a number of potentially useful predictive models relative to explanatory covariates for demography, human disturbance, and habitat. Using the most parsimonious models, we generated risk ratios, hypothetical survival curves, and a map of the spatial distribution of high-risk areas across the recovery zone. Our results were in agreement with past studies of mortality factors for Yellowstone grizzly bears. Holding other covariates constant, mortality was highest for bears that were subjected to repeated management actions and inhabited areas with high road densities outside Yellowstone National Park. Hazard models developed with covariates descriptive of foraging habitats were not the most parsimonious, but they suggested that high-elevation areas offered lower risks of mortality when compared to agricultural areas.

The 2017 Maple Creek Seismic Swarm in Yellowstone National Park

NASA Astrophysics Data System (ADS)

Pang, G.; Hale, J. M.; Farrell, J.; Burlacu, R.; Koper, K. D.; Smith, R. B.

2017-12-01

The University of Utah Seismograph Stations (UUSS) performs near-real-time monitoring of seismicity in the region around Yellowstone National Park in partnership with the United States Geological Survey and the National Park Service. UUSS operates and maintains 29 seismic stations with network code WY (short-period, strong-motion, and broadband) and records data from five other seismic networks—IW, MB, PB, TA, and US—to enhance the location capabilities in the Yellowstone region. A seismic catalog is produced using a conventional STA/LTA detector and single-event location techniques (Hypoinverse). On June 12, 2017, a seismic swarm began in Yellowstone National Park about 5 km east of Hebgen Lake. The swarm is adjacent to the source region of the 1959 MW 7.3 Hebgen Lake earthquake, in an area corresponding to positive Coulumb stress change from that event. As of Aug. 1, 2017, the swarm consists of 1481 earthquakes with 1 earthquake above magnitude 4, 8 earthquakes in the magnitude 3 range, 115 earthquakes in the magnitude 2 range, 469 earthquakes in the magnitude 1 range, 856 earthquakes in the magnitude 0 range, 22 earthquakes with negative magnitudes, and 10 earthquakes with no magnitude. Earthquake depths are mostly between 3 and 10 km and earthquake depth increases toward the northwest. Moment tensors for the 2 largest events (3.6 MW and 4.4. MW) show strike-slip faulting with T axes oriented NE-SW, consistent with the regional stress field. We are currently using waveform cross-correlation methods to measure differential travel times that are being used with the GrowClust program to generate high-accuracy relative relocations. Those locations will be used to identify structures in the seismicity and make inferences about the tectonic and magmatic processes causing the swarm.

A Riparian Approach to Dendrochronological Flow Reconstruction, Yellowstone River, Montana

NASA Astrophysics Data System (ADS)

Schook, D. M.; Rathburn, S. L.; Friedman, J. M.

2015-12-01

Tree ring-based flow reconstructions can reveal river discharge variability over durations far exceeding the gauged record, building perspective for both the measured record and future flows. We use plains cottonwood (Populus deltoides subsp. monilifera) tree rings collected from four rivers to reconstruct flow history of the Yellowstone River near its confluence with the Missouri River. Upland trees in dry regions are typically used in flow reconstruction because their annual growth is controlled by the same precipitation that drives downstream flow, but our study improves flow reconstruction by including floodplain trees that are directly affected by the river. Cores from over 1000 cottonwoods along the Yellowstone, Powder, Little Missouri, and Redwater Rivers were collected from within a 170 km radius to reconstruct flows using the Age Curve Standardization technique in a multiple regression analysis. The large sample from trees spanning many age classes allows us to use only the rings that were produced when each tree was less than 50 years old and growth was most strongly correlated to river discharge. Using trees from a range of rivers improves our ability to differentiate between growth resulting from local precipitation and river flow, and we show that cottonwood growth differs across these neighboring rivers having different watersheds. Using the program Seascorr, tree growth is found to better correlated to seasonal river discharge (R = 0.69) than to local precipitation (R = 0.45). Our flow reconstruction reveals that the most extreme multi-year or multi-decade drought periods of the last 250 years on either the Yellowstone (1817-1821) or Powder (1846-1865) Rivers are missed by the gauged discharge record. Across all sites, we document increased growth in the 20th century compared to the 19th, a finding unattainable with conventional methods but having important implications for flow management.

Siliceous Shrubs in Yellowstone's Hot Springs: Implications for Exobiological Investigations

NASA Technical Reports Server (NTRS)

Guidry, S. A.; Chafetz, H. S.

2003-01-01

Potential relict hot springs have been identified on Mars and, using the Earth as an analog, Martian hot springs are postulated to be an optimal locality for recognizing preserved evidence of extraterrestrial life. Distinctive organic and inorganic biomarkers are necessary to recognize preserved evidence of life in terrestrial and extraterrestrial hot spring accumulations. Hot springs in Yellowstone National Park, Wyoming, U.S.A., contain a wealth of information about primitive microbial life and associated biosignatures that may be useful for future exobiological investigations. Numerous siliceous hot springs in Yellowstone contain abundant, centimeter-scale, spinose precipitates of opaline silica (opal-A). Although areally extensive in siliceous hot spring discharge channel facies, these spinose forms have largely escaped attention. These precipitates referred to as shrubs, consist of porous aggregates of spinose opaline silica that superficially resemble miniature woody plants, i.e., the term shrubs. Shrubs in carbonate precipitating systems have received considerable attention, and represent naturally occurring biotically induced precipitates. As such, shrubs have great potential as hot spring environmental indicators and, more importantly, proxies for pre-existing microbial life.

Distribution of grizzly bears in the Greater Yellowstone Ecosystem, 2004

USGS Publications Warehouse

Schwartz, C.C.; Haroldson, M.A.; Gunther, K.; Moody, D.

2006-01-01

The US Fish and Wildlife Service (USFWS) proposed delisting the Yellowstone grizzly bear (Ursus arctos horribilis) in November 2005. Part of that process required knowledge of the most current distribution of the species. Here, we update an earlier estimate of occupied range (1990–2000) with data through 2004. We used kernel estimators to develop distribution maps of occupied habitats based on initial sightings of unduplicated females (n = 481) with cubs of the year, locations of radiomarked bears (n = 170), and spatially unique locations of conflicts, confrontations, and mortalities (n = 1,075). Although each data set was constrained by potential sampling bias, together they provided insight into areas in the Greater Yellowstone Ecosystem (GYE) currently occupied by grizzly bears. The current distribution of 37,258 km2 (1990–2004) extends beyond the distribution map generated with data from 1990–2000 (34,416 km2 ). Range expansion is particularly evident in parts of the Caribou–Targhee National Forest in Idaho and north of Spanish Peaks on the Gallatin National Forest in Montana.

75 FR 30295 - Modification of Class E Airspace; West Yellowstone, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-01

... Positioning System (GPS) Standard Instrument Approach Procedure (SIAP) at West Yellowstone Airport. This will... also includes minor adjustments in the legal description of the airspace. DATES: Effective date, 0901... executing new RNAV (GPS) SIAP's at the airport. This rule also makes minor changes to the legal description...

Modeling Resource Hotspots: Critical Linkages and Processes

NASA Astrophysics Data System (ADS)

Daher, B.; Mohtar, R.; Pistikopoulos, E.; McCarl, B. A.; Yang, Y.

2017-12-01

Growing demands for interconnected resources emerge in the form of hotspots of varying characteristics. The business as usual allocation model cannot address the current, let alone anticipated, complex and highly interconnected resource challenges we face. A new paradigm for resource allocation must be adopted: one that identifies cross-sectoral synergies and, that moves away from silos to recognition of the nexus and integration of it. Doing so will result in new opportunities for business growth, economic development, and improved social well-being. Solutions and interventions must be multi-faceted; opportunities should be identified with holistic trade-offs in mind. No single solution fits all: different hotspots will require distinct interventions. Hotspots have varying resource constraints, stakeholders, goals and targets. The San Antonio region represents a complex resource hotspot with promising potential: its rapidly growing population, the Eagle Ford shale play, and the major agricultural activity there makes it a hotspot with many competing demands. Stakeholders need tools to allow them to knowledgeably address impending resource challenges. This study will identify contemporary WEF nexus questions and critical system interlinkages that will inform the modeling of the tightly interconnected resource systems and stresses using the San Antonio Region as a base; it will conceptualize a WEF nexus modeling framework, and develop assessment criteria to inform integrative planning and decision making.

Flood risk assessment of land pollution hotspots

NASA Astrophysics Data System (ADS)

Masi, Matteo; Arrighi, Chiara; Iannelli, Renato

2017-04-01

Among the risks caused by extreme events, the potential spread of pollutants stored in land hotspots due to floods is an aspect that has been rarely examined with a risk-based approach. In this contribution, an attempt to estimate pollution risks related to flood events of land pollution hotspots was carried out. Flood risk has been defined as the combination of river flood hazard, hotspots exposure and vulnerability to contamination of the area, i.e. the expected severity of the environmental impacts. The assessment was performed on a geographical basis, using geo-referenced open data, available from databases of land management institutions, authorities and agencies. The list of land pollution hotspots included landfills and other waste handling facilities (e.g., temporary storage, treatment and recycling sites), municipal wastewater treatment plants, liquid waste treatment facilities and contaminated sites. The assessment was carried out by combining geo-referenced data of pollution hotspots with flood hazard maps. We derived maps of land pollution risk based on geographical and geological properties and source characteristics available from environmental authorities. These included information about soil particle size, soil hydraulic conductivity, terrain slope, type of stored pollutants, the type of facility, capacity, size of the area, land use, etc. The analysis was carried out at catchment scale. The case study of the Arno river basin in Tuscany (central Italy) is presented.

Towards biodiversity hotspots effective for conserving mammals with small geographic ranges

NASA Astrophysics Data System (ADS)

Carrara, Rodolfo; San Blas, Germán; Agrain, Federico; Roig-Juñent, Sergio

2017-01-01

The main goal of using global biodiversity hotspots for conservation purposes is to protect taxa with small geographic ranges because these are highly vulnerable to extinction. However, the extent to what different hotspots types are effective for meeting this goal remains controversial because hotspots have been previously defined as either the richest or most threatened and richest sites in terms of total, endemic or threatened species. In this regard, the use of species richness to set conservation priorities is widely discussed because strategies focused on this diversity measure tend to miss many of the taxa with small geographic ranges. Here we use data on global terrestrial mammal distributions to show that, hotspots of total species, endemism and threat defined in terms of species richness are effective in including 27%, 29% and 11% respectively, of the taxa with small geographic ranges. Whilst, the same hotspot types defined in terms of a simple diversity index, which is a function of species richness and range-size rarity, include 68%, 44% and 90% respectively, of these taxa. In addition, we demonstrate that index hotspot types are highly efficient because they conserve 79% of mammal species (21% more species than richness hotspot types), with 59% of species shared by three hotspot types (31% more than richness hotspot types). These results suggest that selection of different diversity measures to define hotspots may strongly affect the achievement of conservation goals.

Characteristics of suicide hotspots on the Belgian railway network.

PubMed

Debbaut, Kevin; Krysinska, Karolina; Andriessen, Karl

2014-01-01

In 2004, railway suicide accounted for 5.3% of all suicides in Belgium. In 2008, Infrabel (Manager of the Belgian Railway Infrastructure) introduced a railway suicide prevention programme, including identification of suicide hotspots, i.e., areas of the railway network with an elevated incidence of suicide. The study presents an analysis of 43 suicide hotspots based on Infrabel data collected during field visits and semi-structured interviews conducted in mental health facilities in the vicinity of the hotspots. Three major characteristics of the hotspots were accessibility, anonymity, and vicinity of a mental health institution. The interviews identified several risk and protective factors for railway suicide, including the training of staff, introduction of a suicide prevention policy, and the role of the media. In conclusion, a comprehensive railway suicide prevention programme should continuously safeguard and monitor hotspots, and should be embedded in a comprehensive suicide prevention programme in the community.

Creating Conditions for Policy Change in National Parks: Contrasting Cases in Yellowstone and Yosemite

NASA Astrophysics Data System (ADS)

Yochim, Michael J.; Lowry, William R.

2016-05-01

Public agencies face significant political obstacles when they try to change long-standing policies. This paper examines efforts by the U.S. National Park Service to change long-term policies in Yellowstone and Yosemite national parks. We argue that, to be successful, the agency and pro-change allies must expand the sphere of conflict to engage the support of the broader American public through positive framing, supportive science, compelling economic arguments, consistent goals, and the commitment of other institutional actors. We show that the agency is capable of creating these conditions, as in the reintroduction of wolves to Yellowstone, but we argue that this is not always the outcome, as in reducing automobile congestion in Yosemite Valley.

Creating Conditions for Policy Change in National Parks: Contrasting Cases in Yellowstone and Yosemite.

PubMed

Yochim, Michael J; Lowry, William R

2016-05-01

Public agencies face significant political obstacles when they try to change long-standing policies. This paper examines efforts by the U.S. National Park Service to change long-term policies in Yellowstone and Yosemite national parks. We argue that, to be successful, the agency and pro-change allies must expand the sphere of conflict to engage the support of the broader American public through positive framing, supportive science, compelling economic arguments, consistent goals, and the commitment of other institutional actors. We show that the agency is capable of creating these conditions, as in the reintroduction of wolves to Yellowstone, but we argue that this is not always the outcome, as in reducing automobile congestion in Yosemite Valley.

A computer program for estimating instream travel times and concentrations of a potential contaminant in the Yellowstone River, Montana

USGS Publications Warehouse

McCarthy, Peter M.

2006-01-01

The Yellowstone River is very important in a variety of ways to the residents of southeastern Montana; however, it is especially vulnerable to spilled contaminants. In 2004, the U.S. Geological Survey, in cooperation with Montana Department of Environmental Quality, initiated a study to develop a computer program to rapidly estimate instream travel times and concentrations of a potential contaminant in the Yellowstone River using regression equations developed in 1999 by the U.S. Geological Survey. The purpose of this report is to describe these equations and their limitations, describe the development of a computer program to apply the equations to the Yellowstone River, and provide detailed instructions on how to use the program. This program is available online at [http://pubs.water.usgs.gov/sir2006-5057/includes/ytot.xls]. The regression equations provide estimates of instream travel times and concentrations in rivers where little or no contaminant-transport data are available. Equations were developed and presented for the most probable flow velocity and the maximum probable flow velocity. These velocity estimates can then be used to calculate instream travel times and concentrations of a potential contaminant. The computer program was developed so estimation equations for instream travel times and concentrations can be solved quickly for sites along the Yellowstone River between Corwin Springs and Sidney, Montana. The basic types of data needed to run the program are spill data, streamflow data, and data for locations of interest along the Yellowstone River. Data output from the program includes spill location, river mileage at specified locations, instantaneous discharge, mean-annual discharge, drainage area, and channel slope. Travel times and concentrations are provided for estimates of the most probable velocity of the peak concentration and the maximum probable velocity of the peak concentration. Verification of estimates of instream travel times and

Space Radar Image of Yellowstone Park, Wyoming

NASA Image and Video Library

1999-05-01

These two radar images show the majestic Yellowstone National Park, Wyoming, the oldest national park in the United States and home to the world's most spectacular geysers and hot springs. The region supports large populations of grizzly bears, elk and bison. In 1988, the park was burned by one of the most widespread fires to occur in the northern Rocky Mountains in the last 50 years. Surveys indicated that 793,880 acres of land burned. Of that, 41 percent was burned forest, with tree canopies totally consumed by the fire; 35 percent was a combination of unburned, scorched and blackened trees; 13 percent was surface burn under an unburned canopy; 6 percent was non-forest burn; and 5 percent was undifferentiated burn. Six years later, the burned areas are still clearly visible in these false-color radar images obtained by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar on board the space shuttle Endeavour. The image at the left was obtained using the L-band radar channel, horizontally received and vertically transmitted, on the shuttle's 39th orbit on October 2, 1994. The area shown is 45 kilometers by 71 kilometers (28 miles by 44 miles) in size and centered at 44.6 degrees north latitude, 110.7 degrees west longitude. North is toward the top of the image (to the right). Most trees in this area are lodge pole pines at different stages of fire succession. Yellowstone Lake appears as a large dark feature at the bottom of the scene. At right is a map of the forest crown, showing its biomass, or amount of vegetation, which includes foliage and branches. The map was created by inverting SIR-C data and using in situ estimates of crown biomass gathered by the Yellowstone National Biological Survey. The map is displayed on a color scale from blue (rivers and lakes with no biomass) to brown (non-forest areas with crown biomass of less than 4 tons per hectare) to light brown (areas of canopy burn with biomass of between 4 and 12 tons per hectare). Yellow

76 FR 77131 - Special Regulations; Areas of the National Park System, Yellowstone National Park

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-12

... FURTHER INFORMATION CONTACT: Steve Iobst, Deputy Superintendent, Yellowstone National Park, (307) 344-2002... material way the economy, productivity, competition, jobs, the environment, public health or safety, or...

Bounds on geologically current rates of motion of groups of hotspots.

NASA Astrophysics Data System (ADS)

Wang, C.; Gordon, R. G.; Zhang, T.

2017-12-01

It is widely believed that groups of hotspots in different regions of the world are in relative motion at rates of 10 to 30 mm a-1 or more. Here we present a new method for analyzing geologically current motion between groups of hotspots beneath different plates. In an inversion of 56 globally distributed, equally weighted trends of hotspot tracks, the dispersion is dominated by differences in trend between different plates rather than differences within plates. Nonetheless the rate of hotspot motion perpendicular to the direction of absolute plate motion, vperp, differs significantly from zero for only three of ten plates and then by merely 0.3 to 1.4 mm a-1. The global mean upper bound on |vperp| is 3.2 ±2.7 mm a-1. Therefore, groups of hotspots move slowly and can be used to define a global reference frame for plate motions. Further implications for uncertainties in hotspot trends and current plate motion relative to hotspots will be discussed.

Long-term limnological data from the larger lakes of Yellowstone National Park, Wyoming, USA

USGS Publications Warehouse

Theriot, E.C.; Fritz, S.C.; Gresswell, Robert E.

1997-01-01

Long-term limnological data from the four largest lakes in Yellowstone National Park (Yellowstone, Lewis, Shoshone, Heart) are used to characterize their limnology and patterns of temporal and spatial variability. Heart Lake has distinctively high concentrations of dissolved materials, apparently reflecting high thermal inputs. Shoshone and Lewis lakes have the highest total SiO2 concentrations (averaging over 23.5 mg L-1), apparently as a result of the rhyolitic drainage basins. Within Yellowstone Lake spatial variability is low and ephemeral for most measured variables, except that the Southeast Arm has lower average Na concentrations. Seasonal variation is evident for Secchi transparency, pH, and total-SiO2 and probably reflects seasonal changes in phytoplankton biomass and productivity. Total dissolved solids (TDS) and total-SiO2 generally show a gradual decline from the mid-1970s through mid-1980s, followed by a sharp increase. Ratios of Kjeldahl-N to total-PO4 (KN:TP) suggest that the lakes, especially Shoshone, are often nitrogen limited. Kjeldahl-N is positively correlated with winter precipitation, but TP and total-SiO2 are counterintuitively negatively correlated with precipitation. We speculate that increased winter precipitation, rather than watershed fires, increases N-loading which, in turn, leads to increased demand for TP and total SiO2.

The phenology of space: Spatial aspects of bison density dependence in Yellowstone National Park

USGS Publications Warehouse

Taper, M.L.; Meagher, M.; Jerde, C.L.

2000-01-01

The Yellowstone bison represent the only bison population in the United States that survived in the wild the near-extermination of the late 1800's. This paper capitalizes on a unique opportunity provided by the record of the bison population of Yellowstone National Park (YNP). This population has been intensely monitored for almost four decades. The analysis of long-term spatio-temporal data from 1970-1997 supports the following conclusions. 1) Even though the Yellowstone bison herd exhibits an extended period of what appears to be linear growth, this pattern can be explained with classical density dependent dynamics if one realizes that perhaps the primary response of the herd to increased density is range expansion. 2) Several spatial aspects of social behavior in the YNP bison may be behavioral adaptations by the bison to environmental changes. These behavioral strategies may buffer, temporarily at least, bison population dynamics from the immediate repercussions of possible environmental stress and habitat deterioration. 3) Bison ecological carrying capacity for YNP is on the order of 2800 to 3200 animals. 4) There do appear to be indications of changes in the bison dynamics that are associated with increasing use of sections of the interior road system in winter. 5) The possibility of habitat degradation is indicated.

Regeneration and survival of whitebark pine after the 1988 Yellowstone fires

Treesearch

Diana F. Tomback; Anna W. Schoettle; Mario J. Perez; Kristen M. Grompone; Sabine Mellmann-Brown

2011-01-01

Successional whitebark pine (Pinus albicaulis) communities are dependent on fire and other disturbances for renewal (Arno 2001). Where whitebark pine regenerates results from cache site selection by Clark's nutcrackers (Nucifraga columbiana) in relation to the environmental tolerances of seeds and seedlings (Tomback 2001). After the 1988 Yellowstone fires, we...

Methodology and software to detect viral integration site hot-spots

PubMed Central

2011-01-01

Background Modern gene therapy methods have limited control over where a therapeutic viral vector inserts into the host genome. Vector integration can activate local gene expression, which can cause cancer if the vector inserts near an oncogene. Viral integration hot-spots or 'common insertion sites' (CIS) are scrutinized to evaluate and predict patient safety. CIS are typically defined by a minimum density of insertions (such as 2-4 within a 30-100 kb region), which unfortunately depends on the total number of observed VIS. This is problematic for comparing hot-spot distributions across data sets and patients, where the VIS numbers may vary. Results We develop two new methods for defining hot-spots that are relatively independent of data set size. Both methods operate on distributions of VIS across consecutive 1 Mb 'bins' of the genome. The first method 'z-threshold' tallies the number of VIS per bin, converts these counts to z-scores, and applies a threshold to define high density bins. The second method 'BCP' applies a Bayesian change-point model to the z-scores to define hot-spots. The novel hot-spot methods are compared with a conventional CIS method using simulated data sets and data sets from five published human studies, including the X-linked ALD (adrenoleukodystrophy), CGD (chronic granulomatous disease) and SCID-X1 (X-linked severe combined immunodeficiency) trials. The BCP analysis of the human X-linked ALD data for two patients separately (774 and 1627 VIS) and combined (2401 VIS) resulted in 5-6 hot-spots covering 0.17-0.251% of the genome and containing 5.56-7.74% of the total VIS. In comparison, the CIS analysis resulted in 12-110 hot-spots covering 0.018-0.246% of the genome and containing 5.81-22.7% of the VIS, corresponding to a greater number of hot-spots as the data set size increased. Our hot-spot methods enable one to evaluate the extent of VIS clustering, and formally compare data sets in terms of hot-spot overlap. Finally, we show that the

Investigating Avian Influenza Infection Hotspots in Old-World Shorebirds

PubMed Central

Gaidet, Nicolas; Ould El Mamy, Ahmed B.; Cappelle, Julien; Caron, Alexandre; Cumming, Graeme S.; Grosbois, Vladimir; Gil, Patricia; Hammoumi, Saliha; de Almeida, Renata Servan; Fereidouni, Sasan R.; Cattoli, Giovanni; Abolnik, Celia; Mundava, Josphine; Fofana, Bouba; Ndlovu, Mduduzi; Diawara, Yelli; Hurtado, Renata; Newman, Scott H.; Dodman, Tim; Balança, Gilles

2012-01-01

Heterogeneity in the transmission rates of pathogens across hosts or environments may produce disease hotspots, which are defined as specific sites, times or species associations in which the infection rate is consistently elevated. Hotspots for avian influenza virus (AIV) in wild birds are largely unstudied and poorly understood. A striking feature is the existence of a unique but consistent AIV hotspot in shorebirds (Charadriiformes) associated with a single species at a specific location and time (ruddy turnstone Arenaria interpres at Delaware Bay, USA, in May). This unique case, though a valuable reference, limits our capacity to explore and understand the general properties of AIV hotspots in shorebirds. Unfortunately, relatively few shorebirds have been sampled outside Delaware Bay and they belong to only a few shorebird families; there also has been a lack of consistent oropharyngeal sampling as a complement to cloacal sampling. In this study we looked for AIV hotspots associated with other shorebird species and/or with some of the larger congregation sites of shorebirds in the old world. We assembled and analysed a regionally extensive dataset of AIV prevalence from 69 shorebird species sampled in 25 countries across Africa and Western Eurasia. Despite this diverse and extensive coverage we did not detect any new shorebird AIV hotspots. Neither large shorebird congregation sites nor the ruddy turnstone were consistently associated with AIV hotspots. We did, however, find a low but widespread circulation of AIV in shorebirds that contrast with the absence of AIV previously reported in shorebirds in Europe. A very high AIV antibody prevalence coupled to a low infection rate was found in both first-year and adult birds of two migratory sandpiper species, suggesting the potential existence of an AIV hotspot along their migratory flyway that is yet to be discovered. PMID:23029383

Quantile-based permutation thresholds for quantitative trait loci hotspots.

PubMed

Neto, Elias Chaibub; Keller, Mark P; Broman, Andrew F; Attie, Alan D; Jansen, Ritsert C; Broman, Karl W; Yandell, Brian S

2012-08-01

Quantitative trait loci (QTL) hotspots (genomic locations affecting many traits) are a common feature in genetical genomics studies and are biologically interesting since they may harbor critical regulators. Therefore, statistical procedures to assess the significance of hotspots are of key importance. One approach, randomly allocating observed QTL across the genomic locations separately by trait, implicitly assumes all traits are uncorrelated. Recently, an empirical test for QTL hotspots was proposed on the basis of the number of traits that exceed a predetermined LOD value, such as the standard permutation LOD threshold. The permutation null distribution of the maximum number of traits across all genomic locations preserves the correlation structure among the phenotypes, avoiding the detection of spurious hotspots due to nongenetic correlation induced by uncontrolled environmental factors and unmeasured variables. However, by considering only the number of traits above a threshold, without accounting for the magnitude of the LOD scores, relevant information is lost. In particular, biologically interesting hotspots composed of a moderate to small number of traits with strong LOD scores may be neglected as nonsignificant. In this article we propose a quantile-based permutation approach that simultaneously accounts for the number and the LOD scores of traits within the hotspots. By considering a sliding scale of mapping thresholds, our method can assess the statistical significance of both small and large hotspots. Although the proposed approach can be applied to any type of heritable high-volume "omic" data set, we restrict our attention to expression (e)QTL analysis. We assess and compare the performances of these three methods in simulations and we illustrate how our approach can effectively assess the significance of moderate and small hotspots with strong LOD scores in a yeast expression data set.

Magnetotelluric Investigations of the Yellowstone Caldera: Understanding the Emplacement of Crustal Magma Bodies

NASA Astrophysics Data System (ADS)

Gurrola, R. M.; Neal, B. A.; Bennington, N. L.; Cronin, R.; Fry, B.; Hart, L.; Imamura, N.; Kelbert, A.; Bowles-martinez, E.; Miller, D. J.; Scholz, K. J.; Schultz, A.

2017-12-01

Wideband magnetotellurics (MT) presents an ideal method for imaging conductive shallow magma bodies associated with contemporary Yellowstone-Snake River Plain (YSRP) magmatism. Particularly, how do these magma bodies accumulate in the mid to upper crust underlying the Yellowstone Caldera, and furthermore, what role do hydrothermal fluids play in their ascent? During the summer 2017 field season, two field teams from Oregon State University and the University of Wisconsin-Madison installed forty-four wideband MT stations within and around the caldera, and using data slated for joint 3-D inversion with existing seismic data, two 2-D vertical conductivity sections of the crust and upper mantle were constructed. These models, in turn, provide preliminary insight into the emplacement of crustal magma bodies and hydrothermal processes in the YSRP region.

Hot-spot durability testing of amorphous cells and modules

NASA Technical Reports Server (NTRS)

Gonzalez, Charles; Jetter, Elizabeth

1985-01-01

This paper discusses the results of a study to determine the hot-spot susceptibility of amorphous-silicon (a-Si) cells and modules, and to provide guidelines for reducing that susceptibility. Amorphous-Si cells are shown to have hot-spot susceptibility levels similar to crystalline-silicon (C-Si) cells. This premise leads to the fact that the same general guidelines must apply to protecting a-Si cells from hot-spot stressing that apply to C-Si cells. Recommendations are made on ways of reducing a-Si module hot-spot susceptibility including the traditional method of using bypass diodes and a new method unique to thin-film cells, limiting the string current by limiting cell area.

Ghosts of Yellowstone: Multi-Decadal Histories of Wildlife Populations Captured by Bones on a Modern Landscape

PubMed Central

Miller, Joshua H.

2011-01-01

Natural accumulations of skeletal material (death assemblages) have the potential to provide historical data on species diversity and population structure for regions lacking decades of wildlife monitoring, thereby contributing valuable baseline data for conservation and management strategies. Previous studies of the ecological and temporal resolutions of death assemblages from terrestrial large-mammal communities, however, have largely focused on broad patterns of community composition in tropical settings. Here, I expand the environmental sampling of large-mammal death assemblages into a temperate biome and explore more demanding assessments of ecological fidelity by testing their capacity to record past population fluctuations of individual species in the well-studied ungulate community of Yellowstone National Park (Yellowstone). Despite dramatic ecological changes following the 1988 wildfires and 1995 wolf re-introduction, the Yellowstone death assemblage is highly faithful to the living community in species richness and community structure. These results agree with studies of tropical death assemblages and establish the broad capability of vertebrate remains to provide high-quality ecological data from disparate ecosystems and biomes. Importantly, the Yellowstone death assemblage also correctly identifies species that changed significantly in abundance over the last 20 to ∼80 years and the directions of those shifts (including local invasions and extinctions). The relative frequency of fresh versus weathered bones for individual species is also consistent with documented trends in living population sizes. Radiocarbon dating verifies the historical source of bones from Equus caballus (horse): a functionally extinct species. Bone surveys are a broadly valuable tool for obtaining population trends and baseline shifts over decadal-to-centennial timescales. PMID:21464921

Storage of Explosive versus Effusive Rhyolite Magma at the Yellowstone Volcanic Center

NASA Astrophysics Data System (ADS)

Gardner, J. E.

2007-12-01

The Yellowstone volcanic center has erupted more than 900 km3 of rhyolitic magma in the last 600,000 years (1). Most of that magma extruded as large lava flows, with only a few known explosive eruptions. Why have explosive eruptions been so rare in the recent history of the Yellowstone volcanic system? To explore that question, we focus on the Tuff of Bluff Point (TBP), about 50 km3 of magma that explosively erupted 173 ka, forming the West Thumb caldera (1). Like most other recent eruptions of Yellowstone, TBP is high silica rhyolite, with phenocrysts of quartz, sanidine, and minor ferro-pyroxenes and Fe-Ti oxides. Fe-Ti oxide and pyroxene compositions indicate that the magma had equilibrated at an oxygen fugacity equal to the QFM buffer. Rehomogenized glass inclusions (n=7) in quartz contain 2.2-3.1 wt.% water and between 400-650 ppm CO2. Those volatile contents indicate storage pressures of 90-160 MPa. Ubiquitous pyrrhotite shows that the magma was sulfur saturated, and most likely volatile saturated. The co-existing fluid would be only 42-47% water. Cathodoluminescence (CL) images of quartz phenocrysts reveal mainly concentric growth zones, with occasional dissolution boundaries present. Ti contents in quartz generally decrease from core to rim, indicating cooling of the magma, although the relative temperature changes recorded are only 10-15°, with only minor changes across dissolution boundaries. To put our observations in perspective of the recent Yellowstone magma system, we have begun examining some of the recent rhyolitic lavas, including the Pitchstone Plateau (PP), a single homogeneous lava flow of 70 km3 that erupted 79 ka (1). CL images also reveal mainly concentric quartz growth, with few dissolution boundaries obvious. Ti contents in quartz also generally decrease from core to rim, but are uniformly lower than in those in TBP, suggesting that PP magma was colder than TBP magma. Glass inclusions (n=20) in PP are generally water poor and rarely

Fine-scale maps of recombination rates and hotspots in the mouse genome.

PubMed

Brunschwig, Hadassa; Levi, Liat; Ben-David, Eyal; Williams, Robert W; Yakir, Benjamin; Shifman, Sagiv

2012-07-01

Recombination events are not uniformly distributed and often cluster in narrow regions known as recombination hotspots. Several studies using different approaches have dramatically advanced our understanding of recombination hotspot regulation. Population genetic data have been used to map and quantify hotspots in the human genome. Genetic variation in recombination rates and hotspots usage have been explored in human pedigrees, mouse intercrosses, and by sperm typing. These studies pointed to the central role of the PRDM9 gene in hotspot modulation. In this study, we used single nucleotide polymorphisms (SNPs) from whole-genome resequencing and genotyping studies of mouse inbred strains to estimate recombination rates across the mouse genome and identified 47,068 historical hotspots--an average of over 2477 per chromosome. We show by simulation that inbred mouse strains can be used to identify positions of historical hotspots. Recombination hotspots were found to be enriched for the predicted binding sequences for different alleles of the PRDM9 protein. Recombination rates were on average lower near transcription start sites (TSS). Comparing the inferred historical recombination hotspots with the recent genome-wide mapping of double-strand breaks (DSBs) in mouse sperm revealed a significant overlap, especially toward the telomeres. Our results suggest that inbred strains can be used to characterize and study the dynamics of historical recombination hotspots. They also strengthen previous findings on mouse recombination hotspots, and specifically the impact of sequence variants in Prdm9.

A measurement concept for hot-spot BRDFs from space

NASA Technical Reports Server (NTRS)

Gerstl, S.A.W.

1996-01-01

Several concepts for canopy hot-spot measurements from space have been investigated. The most promising involves active illumination and bistatic detection that would allow hot-spot angular distribution (BRDF) measurements from space in a search-light mode. The concept includes a pointable illumination source, such as a laser operating at an atmospheric window wavelength, coupled with a number of high spatial-resolution detectors that are clustered around the illumination source in space, receiving photons nearly coaxial with the reto-reflection direction. Microwave control and command among the satellite cluster would allow orienting the direction of the laser beam as well as the focusing detectors simultaneously so that the coupled system can function like a search light with almost unlimited pointing capabilities. The concept is called the Hot-Spot Search-Light (HSSL) satellite. A nominal satellite altitude of 600 km will allow hot-spot BRDF measurements out to about 18 degrees phase angle. The distributed are taking radiometric measurements of the intensity wings of the hot-spot angular distribution without the need for complex imaging detectors. The system can be operated at night for increased signal-to-noise ratio. This way the hot-spot angular signatures can be quantified and parameterized in sufficient detail to extract the biophysical information content of plant architectures.

75 FR 27579 - Bison Brucellosis Remote Vaccination, Draft Environmental Impact Statement, Yellowstone National...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

... INFORMATION CONTACT: Rick Wallen, Bison Ecology and Management Office, Yellowstone National Park, P.O. Box 168... may submit your comments by any one of several methods. You may mail comments to the Bison Ecology and...

Fueling a Crisis: Public Argument and the 1988 Yellowstone Fire Debate.

ERIC Educational Resources Information Center

Hardy-Short, Dayle; Short, C. Brant

Debate surrounding the 1988 Yellowstone National Park fires provides material for a case study into the relationship between a crisis and public argument. Studies like this reflect the importance of a recent trend in higher education, namely, the analysis of environmental issues from different academic perspectives. In this case, analysis of…

Geochemical evidence for hydroclimatic variability over the last 2460 years from Crevice Lake in Yellowstone National Park, USA

USGS Publications Warehouse

Stevens, L.R.; Dean, W.E.

2008-01-01

A 2460-year-long hydroclimatic record for Crevice Lake, Yellowstone National Park, Montana was constructed from the ??18O values of endogenic carbonates. The ??18O record is compared to the Palmer Hydrologic Drought Index (PHDI) and Pacific Decadal Oscillation (PDO) indices, as well as inferred discharge of the Yellowstone River. During the last century, high ??18O values coincide with drought conditions and the warm phase of the PDO index. Low ??18O values coincide with wet years and a negative PDO index. Comparison of tree-ring inferred discharge of the Yellowstone River with the ??18O record over the last 300 years indicates that periods of high discharge (i.e., wet winters with significant snow pack) correspond with low ??18O values. Extrapolating this relationship we infer wet winters and high river discharge for the periods of 1090-1030, 970-870, 670-620, and 500-430 cal years BP. The wet intervals at 670 and 500 cal BP are synchronous with similar events in Banff, Canada and Walker Lake, Nevada. The wet intervals at 970 and 670 cal BP overlap with wet intervals at Walker Lake and major drought events identified in the western Great Basin. These results suggest that the northern border of Yellowstone National Park straddles the boundary between Northern Rocky Mountains and Great Basin climate regimes. ?? 2007 Elsevier Ltd and INQUA.

Exploration and discovery in Yellowstone Lake: results from high-resolution sonar imaging, seismic reflection profiling, and submersible studies

NASA Astrophysics Data System (ADS)

Morgan, L. A.; Shanks, W. C.; Lovalvo, D. A.; Johnson, S. Y.; Stephenson, W. J.; Pierce, K. L.; Harlan, S. S.; Finn, C. A.; Lee, G.; Webring, M.; Schulze, B.; Dühn, J.; Sweeney, R.; Balistrieri, L.

2003-04-01

'No portion of the American continent is perhaps so rich in wonders as the Yellow Stone' (F.V. Hayden, September 2, 1874) Discoveries from multi-beam sonar mapping and seismic reflection surveys of the northern, central, and West Thumb basins of Yellowstone Lake provide new insight into the extent of post-collapse volcanism and active hydrothermal processes occurring in a large lake environment above a large magma chamber. Yellowstone Lake has an irregular bottom covered with dozens of features directly related to hydrothermal, tectonic, volcanic, and sedimentary processes. Detailed bathymetric, seismic reflection, and magnetic evidence reveals that rhyolitic lava flows underlie much of Yellowstone Lake and exert fundamental control on lake bathymetry and localization of hydrothermal activity. Many previously unknown features have been identified and include over 250 hydrothermal vents, several very large (>500 m diameter) hydrothermal explosion craters, many small hydrothermal vent craters (˜1-200 m diameter), domed lacustrine sediments related to hydrothermal activity, elongate fissures cutting post-glacial sediments, siliceous hydrothermal spire structures, sublacustrine landslide deposits, submerged former shorelines, and a recently active graben. Sampling and observations with a submersible remotely operated vehicle confirm and extend our understanding of the identified features. Faults, fissures, hydrothermally inflated domal structures, hydrothermal explosion craters, and sublacustrine landslides constitute potentially significant geologic hazards. Toxic elements derived from hydrothermal processes also may significantly affect the Yellowstone ecosystem.

Reversing storm hotspots on sandy beaches: Spatial and temporal characteristics

USGS Publications Warehouse

List, J.H.; Farris, A.S.; Sullivan, C.

2006-01-01

Coastal erosion hotspots are defined as sections of coast that exhibit significantly higher rates of erosion than adjacent areas. This paper describes the spatial and temporal characteristics of a recently identified type of coastal erosion hotspot, which forms in response to storms on uninterrupted sandy coasts largely free from human intervention. These are referred to here as reversing storm hotspots because the erosion is reversed by accretion of a similar magnitude to the storm-induced erosion. The accretion occurs within a few days or weeks of fair weather after the storm. Reversing storm hotspots observed here, on two US east coast beaches, have a longshore length averaging 3.86 km, a cross-shore excursion (magnitude of erosion or accretion) averaging 15.4 m, and a time scale of days to weeks associated with individual storm events. These spatial and temporal scales clearly distinguish reversing storm hotspots from previously described forms of longshore variability in erosion, including those attributed to several types of shoreline undulations and hotspots associated with long-term shoreline change. 

A fluid-driven earthquake swarm on the margin of the Yellowstone caldera

USGS Publications Warehouse

Shelly, David R.; Hill, David P.; Massin, Frederick; Farrell, Jamie; Smith, Robert B.; Taira, Taka'aki

2013-01-01

Over the past several decades, the Yellowstone caldera has experienced frequent earthquake swarms and repeated cycles of uplift and subsidence, reflecting dynamic volcanic and tectonic processes. Here, we examine the detailed spatial-temporal evolution of the 2010 Madison Plateau swarm, which occurred near the northwest boundary of the Yellowstone caldera. To fully explore the evolution of the swarm, we integrated procedures for seismic waveform-based earthquake detection with precise double-difference relative relocation. Using cross-correlation of continuous seismic data and waveform templates constructed from cataloged events, we detected and precisely located 8710 earthquakes during the three-week swarm, nearly four times the number of events included in the standard catalog. This high-resolution analysis reveals distinct migration of earthquake activity over the course of the swarm. The swarm initiated abruptly on January 17, 2010 at about 10 km depth and expanded dramatically outward (both shallower and deeper) over time, primarily along a NNW-striking, ~55º ENE-dipping structure. To explain these characteristics, we hypothesize that the swarm was triggered by the rupture of a zone of confined high-pressure aqueous fluids into a pre-existing crustal fault system, prompting release of accumulated stress. The high-pressure fluid injection may have been accommodated by hybrid shear and dilatational failure, as is commonly observed in exhumed hydrothermally affected fault zones. This process has likely occurred repeatedly in Yellowstone as aqueous fluids exsolved from magma migrate into the brittle crust, and it may be a key element in the observed cycles of caldera uplift and subsidence.

Plate tectonics and hotspots: the third dimension.

PubMed

Anderson, D L; Tanimoto, T; Zhang, Y S

1992-06-19

High-resolution seismic tomographic models of the upper mantle provide powerful new constraints on theories of plate tectonics and hotspots. Midocean ridges have extremely low seismic velocities to a depth of 100 kilometers. These low velocities imply partial melting. At greater depths, low-velocity and high-velocity anomalies record, respectively, previous positions of migrating ridges and trenches. Extensional, rifting, and hotspot regions have deep (> 200 kilometers) low-velocity anomalies. The upper mantle is characterized by vast domains of high temperature rather than small regions surrounding hotspots; the asthenosphere is not homogeneous or isothermal. Extensive magmatism requires a combination of hot upper mantle and suitable lithospheric conditions. High-velocity regions of the upper 200 kilometers of the mantle correlate with Archean cratons.

Fire, red squirrels, whitebark pine, and Yellowstone grizzly bears

USGS Publications Warehouse

Podruzny, Shannon; Reinhart, Daniel P.; Mattson, David J.

1999-01-01

Whitebark pine (Pinus albicaulis) habitats are important to Yellowstone grizzly bears (Ursus arctos) as refugia and sources of food. Ecological relationships between whitebark pine, red squirrels (Tamiasciurus hudsonicus), and grizzly bear use of pine seeds on Mt. Washburn in Yellowstone National Park, Wyoming, were examined during 1984-86. Following large-scale fires in 1988, we repeated the study in 1995-97 to examine the effects of fire on availability of whitebark pine seed in red squirrel middens and on bear use of middens. Half of the total length of the original line transects burned. We found no red squirrel middens in burned areas. Post-fire linear-abundance (no./km) of active squirrel middens that were pooled from burned and unburned areas decreased 27% compared to pre-fire abundance, but increased in unburned portions of some habitat types. Mean size of active middens decreased 54% post-fire. Use of pine seeds by bears (linear abundance of excavated middens) in pooled burned and unburned habitats decreased by 64%, likely due to the combined effects of reduced midden availability and smaller midden size. We discourage any further large-scale losses of seed producing trees from management-prescribed fires or timber harvesting until the effects of fire on ecological relationships in the whitebark pine zone are better understood.

75 FR 4842 - Winter Use Plan, Environmental Impact Statement, Yellowstone National Park

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-29

... establish a management framework that allows the public to experience Yellowstone's unique winter resources... the environmental effects of winter use on air quality and visibility, wildlife, natural soundscapes... U.S. Forest Service. A scoping brochure has been prepared that details the issues identified to date...

Seeking a scientific approach to backcountry management in Yellowstone National Park

Treesearch

S. Thomas Olliff; Sue Consolo Murphy

2000-01-01

Three criteria are used to assess how Yellowstone’s wilderness managers incorporate science into management: preciousness, vulnerability and responsiveness to management. Four observations are proposed. First, where scientists lead, managers will follow. Scientists that leave the best trail will be followed most closely. Second, managers need to refocus efforts on...

The potential of shifting recombination hotspots to increase genetic gain in livestock breeding.

PubMed

Gonen, Serap; Battagin, Mara; Johnston, Susan E; Gorjanc, Gregor; Hickey, John M

2017-07-04

This study uses simulation to explore and quantify the potential effect of shifting recombination hotspots on genetic gain in livestock breeding programs. We simulated three scenarios that differed in the locations of quantitative trait nucleotides (QTN) and recombination hotspots in the genome. In scenario 1, QTN were randomly distributed along the chromosomes and recombination was restricted to occur within specific genomic regions (i.e. recombination hotspots). In the other two scenarios, both QTN and recombination hotspots were located in specific regions, but differed in whether the QTN occurred outside of (scenario 2) or inside (scenario 3) recombination hotspots. We split each chromosome into 250, 500 or 1000 regions per chromosome of which 10% were recombination hotspots and/or contained QTN. The breeding program was run for 21 generations of selection, after which recombination hotspot regions were kept the same or were shifted to adjacent regions for a further 80 generations of selection. We evaluated the effect of shifting recombination hotspots on genetic gain, genetic variance and genic variance. Our results show that shifting recombination hotspots reduced the decline of genetic and genic variance by releasing standing allelic variation in the form of new allele combinations. This in turn resulted in larger increases in genetic gain. However, the benefit of shifting recombination hotspots for increased genetic gain was only observed when QTN were initially outside recombination hotspots. If QTN were initially inside recombination hotspots then shifting them decreased genetic gain. Shifting recombination hotspots to regions of the genome where recombination had not occurred for 21 generations of selection (i.e. recombination deserts) released more of the standing allelic variation available in each generation and thus increased genetic gain. However, whether and how much increase in genetic gain was achieved by shifting recombination hotspots depended

Sampling effects on the identification of roadkill hotspots: Implications for survey design.

PubMed

Santos, Sara M; Marques, J Tiago; Lourenço, André; Medinas, Denis; Barbosa, A Márcia; Beja, Pedro; Mira, António

2015-10-01

Although locating wildlife roadkill hotspots is essential to mitigate road impacts, the influence of study design on hotspot identification remains uncertain. We evaluated how sampling frequency affects the accuracy of hotspot identification, using a dataset of vertebrate roadkills (n = 4427) recorded over a year of daily surveys along 37 km of roads. "True" hotspots were identified using this baseline dataset, as the 500-m segments where the number of road-killed vertebrates exceeded the upper 95% confidence limit of the mean, assuming a Poisson distribution of road-kills per segment. "Estimated" hotspots were identified likewise, using datasets representing progressively lower sampling frequencies, which were produced by extracting data from the baseline dataset at appropriate time intervals (1-30 days). Overall, 24.3% of segments were "true" hotspots, concentrating 40.4% of roadkills. For different groups, "true" hotspots accounted from 6.8% (bats) to 29.7% (small birds) of road segments, concentrating from <40% (frogs and toads, snakes) to >60% (lizards, lagomorphs, carnivores) of roadkills. Spatial congruence between "true" and "estimated" hotspots declined rapidly with increasing time interval between surveys, due primarily to increasing false negatives (i.e., missing "true" hotspots). There were also false positives (i.e., wrong "estimated" hotspots), particularly at low sampling frequencies. Spatial accuracy decay with increasing time interval between surveys was higher for smaller-bodied (amphibians, reptiles, small birds, small mammals) than for larger-bodied species (birds of prey, hedgehogs, lagomorphs, carnivores). Results suggest that widely used surveys at weekly or longer intervals may produce poor estimates of roadkill hotspots, particularly for small-bodied species. Surveying daily or at two-day intervals may be required to achieve high accuracy in hotspot identification for multiple species. Copyright © 2015 Elsevier Ltd. All rights reserved.

HIV-1 vaccine-induced T-cell responses cluster in epitope hotspots that differ from those induced in natural infection with HIV-1.

PubMed

Hertz, Tomer; Ahmed, Hasan; Friedrich, David P; Casimiro, Danilo R; Self, Steven G; Corey, Lawrence; McElrath, M Juliana; Buchbinder, Susan; Horton, Helen; Frahm, Nicole; Robertson, Michael N; Graham, Barney S; Gilbert, Peter

2013-01-01

Several recent large clinical trials evaluated HIV vaccine candidates that were based on recombinant adenovirus serotype 5 (rAd-5) vectors expressing HIV-derived antigens. These vaccines primarily elicited T-cell responses, which are known to be critical for controlling HIV infection. In the current study, we present a meta-analysis of epitope mapping data from 177 participants in three clinical trials that tested two different HIV vaccines: MRKAd-5 HIV and VRC-HIVAD014-00VP. We characterized the population-level epitope responses in these trials by generating population-based epitope maps, and also designed such maps using a large cohort of 372 naturally infected individuals. We used these maps to address several questions: (1) Are vaccine-induced responses randomly distributed across vaccine inserts, or do they cluster into immunodominant epitope hotspots? (2) Are the immunodominance patterns observed for these two vaccines in three vaccine trials different from one another? (3) Do vaccine-induced hotspots overlap with epitope hotspots induced by chronic natural infection with HIV-1? (4) Do immunodominant hotspots target evolutionarily conserved regions of the HIV genome? (5) Can epitope prediction methods be used to identify these hotspots? We found that vaccine responses clustered into epitope hotspots in all three vaccine trials and some of these hotspots were not observed in chronic natural infection. We also found significant differences between the immunodominance patterns generated in each trial, even comparing two trials that tested the same vaccine in different populations. Some of the vaccine-induced immunodominant hotspots were located in highly variable regions of the HIV genome, and this was more evident for the MRKAd-5 HIV vaccine. Finally, we found that epitope prediction methods can partially predict the location of vaccine-induced epitope hotspots. Our findings have implications for vaccine design and suggest a framework by which different

Identifying Interactions that Determine Fragment Binding at Protein Hotspots.

PubMed

Radoux, Chris J; Olsson, Tjelvar S G; Pitt, Will R; Groom, Colin R; Blundell, Tom L

2016-05-12

Locating a ligand-binding site is an important first step in structure-guided drug discovery, but current methods do little to suggest which interactions within a pocket are the most important for binding. Here we illustrate a method that samples atomic hotspots with simple molecular probes to produce fragment hotspot maps. These maps specifically highlight fragment-binding sites and their corresponding pharmacophores. For ligand-bound structures, they provide an intuitive visual guide within the binding site, directing medicinal chemists where to grow the molecule and alerting them to suboptimal interactions within the original hit. The fragment hotspot map calculation is validated using experimental binding positions of 21 fragments and subsequent lead molecules. The ligands are found in high scoring areas of the fragment hotspot maps, with fragment atoms having a median percentage rank of 97%. Protein kinase B and pantothenate synthetase are examined in detail. In each case, the fragment hotspot maps are able to rationalize a Free-Wilson analysis of SAR data from a fragment-based drug design project.

Dynamically supported geoid highs over hotspots: Observation and theory

NASA Technical Reports Server (NTRS)

Richards, M. A.; Hager, B. H.; Sleep, N. H.

1986-01-01

Hotspots are associated with long wavelength geoid highs, an association that is even stronger when the geoid highs associated with subduction zones are removed. These associations are quantified by expanding the hotspot distribution in spherical harmonics and calculating correlation coefficients as a function of harmonic degree. The hotspot distribution spectrum is essentially white, with peaks at degrees 2 and 6. It is correlated positively with the slab residual geoid for degrees 2 to 6, with low seismic velocity in the lower mantle at degree 2, and with low seismic velocity in the upper mantle at degree 6. A variety of fluid mechanical models were tested for hotspots, including lithospheric delamination and hot plumes, by calculating their predicted dynamic geoid responses and comparing them to the observations. These models include the effects of temperature dependent rheology. The preferred hotspot model, based on observations of the geoid and seismic tomography, has plumes preferentially occurring in regions of large scale background temperature highs in a mantle with substantial viscosity increase with depth, although other models are possible.

Dynamically supported geoid highs over hotspots - Observation and theory

NASA Technical Reports Server (NTRS)

Richards, Mark A.; Hager, Bradford H.; Sleep, Norman H.

1988-01-01

Hotspots are associated with long wavelength geoid highs, an association that is even stronger when the geoid highs associated with subduction zones are removed. These associations are quantified by expanding the hotspot distribution in spherical harmonics and calculating correlation coefficients as a function of harmonic degree. The hotspot distribution spectrum is essentially white, with peaks at degrees 2 and 6. It is correlated positively with the slab residual geoid for degrees 2 to 6, with low seismic velocity in the lower mantle at degree 2, and with low seismic velocity in the upper mantle at degree 6. A variety of fluid mechanical models were tested for hotspots, including lithospheric delamination and hot plumes, by calculating their predicted dynamic geoid responses and comparing them to the observations. These models include the effects of temperature dependent rheology. The preferred hotspot model, based on observations of the geoid and seismic tomography, has plumes preferentially occurring in regions of large scale background temperature highs in a mantle with substantial viscosity increase with depth, although other models are possible.

Sediment characteristics of the Yellowstone River in the vicinity of a proposed bypass chute near Glendive, Montana, 2011

USGS Publications Warehouse

Hanson, Brent R.

2012-01-01

In 2011, sediment data were collected by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers on the Yellowstone River at the location of a proposed bypass chute. The sediment data were collected to provide an understanding of the sediment dynamics of the given reach of the Yellowstone River. Suspended-sediment concentrations collected at the three sites generally decreased with decreasing streamflow. In general, the highest suspendedsediment concentrations were found near the channel bed and towards the center of the channel with lower suspendedsediment concentrations near the channel banks and water surface. Suspended sediment was the primary component of the total sediment load for all three sampling locations on the Yellowstone River and contributed at least 98 percent of the total sediment load at each of the three sites. The amount of bedload measured at the three sites was a smaller load in comparison with the suspended-sediment load.

Advanced in-production hotspot prediction and monitoring with micro-topography

NASA Astrophysics Data System (ADS)

Fanton, P.; Hasan, T.; Lakcher, A.; Le-Gratiet, B.; Prentice, C.; Simiz, J.-G.; La Greca, R.; Depre, L.; Hunsche, S.

2017-03-01

At 28nm technology node and below, hot spot prediction and process window control across production wafers have become increasingly critical to prevent hotspots from becoming yield-limiting defects. We previously established proof of concept for a systematic approach to identify the most critical pattern locations, i.e. hotspots, in a reticle layout by computational lithography and combining process window characteristics of these patterns with across-wafer process variation data to predict where hotspots may become yield impacting defects [1,2]. The current paper establishes the impact of micro-topography on a 28nm metal layer, and its correlation with hotspot best focus variations across a production chip layout. Detailed topography measurements are obtained from an offline tool, and pattern-dependent best focus (BF) shifts are determined from litho simulations that include mask-3D effects. We also establish hotspot metrology and defect verification by SEM image contour extraction and contour analysis. This enables detection of catastrophic defects as well as quantitative characterization of pattern variability, i.e. local and global CD uniformity, across a wafer to establish hotspot defect and variability maps. Finally, we combine defect prediction and verification capabilities for process monitoring by on-product, guided hotspot metrology, i.e. with sampling locations being determined from the defect prediction model and achieved prediction accuracy (capture rate) around 75%

Grizzly bear nutrition and ecology studies in Yellowstone National Park

USGS Publications Warehouse

Robbins, Charles T.; Schwartz, Charles C.; Gunther, Kerry A.; Servheen, Christopher

2006-01-01

T HE CHANCE TO SEE a wild grizzly bear is often the first or second reason people give for visiting Yellow - stone National Park. Public interest in bears is closely coupled with a desire to perpetuate this wild symbol of the American West. Grizzly bears have long been described as a wilderness species requiring large tracts of undisturbed habitat. However, in today’s world, most grizzly bears live in close proximity to humans (Schwartz et al. 2003). Even in Yellowstone National Park, the impacts of humans can affect the long-term survival of bears (Gunther et al. 2002). As a consequence, the park has long supported grizzly bear research in an effort to understand these impacts. Most people are familiar with what happened when the park and the State of Montana closed open-pit garbage dumps in the late 1960s and early 1970s, when at least 229 bears died as a direct result of conflict with humans. However, many may not be as familiar with the ongoing changes in the park’s plant and animal communities that have the potential to further alter the park’s ability to support grizzly bears.

'Hotspots' for aggression in licensed drinking venues.

PubMed

Graham, Kathryn; Bernards, Sharon; Osgood, D Wayne; Wells, Samantha

2012-06-01

In order to better understand the social context of barroom aggression, the aim was to identify common locations ('hotspots') for aggression in bars and examine the association of hotspots with aggression severity and environmental characteristics. Aggression hotspots were identified using narrative descriptions and data recorded on premises' floor plans for 1057 incidents of aggression collected in the Safer Bars evaluation. Hierarchical Linear Modelling was used to identify bar-level and night-level characteristics associated with each hotspot. The most common location for aggression was the dance floor (20.0% of incidents) or near the dance floor (11.5%), followed by near the serving bar (15.7%), at tables (13.1%), aisles, hallways and other areas of movement (6.2%), entrance (4.5%) and the pool playing area (4.1%). Hotspots were predicted mainly by bar-level characteristics, with dance floor aggression associated with crowded bars, a high proportion of female and young patrons, lots of sexual activity, a large number of patrons and staff, security staff present, better monitoring and coordination by staff, and people hanging around at closing. Incidents at tables and pool tables tended to occur in bars with the opposite characteristics. Nightly variations in patron intoxication and rowdiness were associated with aggression at tables while variations in crowding and sexual activity were associated with aggression in areas of movement. Incidents outside tended to be more severe. Each aggression location and their associated environments have somewhat different implications for staff training, premises design, policy and prevention. © 2011 Australasian Professional Society on Alcohol and other Drugs.

Sulfolobus islandicus meta-populations in Yellowstone National Park hot springs

USGS Publications Warehouse

Campbell, Kate M.; Kouris, Angela; England, Whitney; Anderson, Rika E.; McCleskey, R. Blaine; Nordstrom, D. Kirk; Whitaker, Rachel J.

2017-01-01

Abiotic and biotic forces shape the structure and evolution of microbial populations. We investigated forces that shape the spatial and temporal population structure of Sulfolobus islandicus by comparing geochemical and molecular analysis from seven hot springs in five regions sampled over 3 years in Yellowstone National Park. Through deep amplicon sequencing, we uncovered 148 unique alleles at two loci whose relative frequency provides clear evidence for independent populations in different hot springs. Although geography controls regional geochemical composition and population differentiation, temporal changes in population were not explained by corresponding variation in geochemistry. The data suggest that the influence of extinction, bottleneck events and/or selective sweeps within a spring and low migration between springs shape these populations. We suggest that hydrologic events such as storm events and surface snowmelt runoff destabilize smaller hot spring environments with smaller populations and result in high variation in the S. islandicus population over time. Therefore, physical abiotic features such as hot spring size and position in the landscape are important factors shaping the stability and diversity of the S. islandicus meta-population within Yellowstone National Park.

Fish-derived nutrient hotspots shape coral reef benthic communities.

PubMed

Shantz, Andrew A; Ladd, Mark C; Schrack, Elizabeth; Burkepile, Deron E

2015-12-01

Animal-derived nutrients play an important role in structuring nutrient regimes within and between ecosystems. When animals undergo repetitive, aggregating behavior through time, they can create nutrient hotspots where rates of biogeochemical activity are higher than those found in the surrounding environment. In turn, these hotspots can influence ecosystem processes and community structure. We examined the potential for reef fishes from the family Haemulidae (grunts) to create nutrient hotspots and the potential impact of these hotspots on reef communities. To do so, we tracked the schooling locations of diurnally migrating grunts, which shelter at reef sites during the day but forage off reef each night, and measured the impact of these fish schools on benthic communities. We found that grunt schools showed a high degree of site fidelity, repeatedly returning to the same coral heads. These aggregations created nutrient hotspots around coral heads where nitrogen and phosphorus delivery was roughly 10 and 7 times the respective rates of delivery to structurally similar sites that lacked schools of these fishes. In turn, grazing rates of herbivorous fishes at grunt-derived hotspots were approximately 3 times those of sites where grunts were rare. These differences in nutrient delivery and grazing led to distinct benthic communities with higher cover of crustose coralline algae and less total algal abundance at grunt aggregation sites. Importantly, coral growth was roughly 1.5 times greater at grunt hotspots, likely due to the important nutrient subsidy. Our results suggest that schooling reef fish and their nutrient subsidies play an important role in mediating community structure on coral reefs and that overfishing may have important negative consequences on ecosystem functions. As such, management strategies must consider mesopredatory fishes in addition to current protection often offered to herbivores and top-tier predators. Furthermore, our results suggest that

Mountain big sagebrush age distribution and relationships on the northern Yellowstone Winter Range

Treesearch

Carl L. Wambolt; Trista L. Hoffman

2001-01-01

This study was conducted within the Gardiner Basin, an especially critical wintering area for native ungulates utilizing the Northern Yellowstone Winter Range. Mountain big sagebrush plants on 33 sites were classified as large (≥22 cm canopy cover), small (

Geomicrobiology of sublacustrine thermal vents in Yellowstone Lake: geochemical controls on microbial community structure and function

PubMed Central

Inskeep, William P.; Jay, Zackary J.; Macur, Richard E.; Clingenpeel, Scott; Tenney, Aaron; Lovalvo, David; Beam, Jacob P.; Kozubal, Mark A.; Shanks, W. C.; Morgan, Lisa A.; Kan, Jinjun; Gorby, Yuri; Yooseph, Shibu; Nealson, Kenneth

2015-01-01

Yellowstone Lake (Yellowstone National Park, WY, USA) is a large high-altitude (2200 m), fresh-water lake, which straddles an extensive caldera and is the center of significant geothermal activity. The primary goal of this interdisciplinary study was to evaluate the microbial populations inhabiting thermal vent communities in Yellowstone Lake using 16S rRNA gene and random metagenome sequencing, and to determine how geochemical attributes of vent waters influence the distribution of specific microorganisms and their metabolic potential. Thermal vent waters and associated microbial biomass were sampled during two field seasons (2007–2008) using a remotely operated vehicle (ROV). Sublacustrine thermal vent waters (circa 50–90°C) contained elevated concentrations of numerous constituents associated with geothermal activity including dissolved hydrogen, sulfide, methane and carbon dioxide. Microorganisms associated with sulfur-rich filamentous “streamer” communities of Inflated Plain and West Thumb (pH range 5–6) were dominated by bacteria from the Aquificales, but also contained thermophilic archaea from the Crenarchaeota and Euryarchaeota. Novel groups of methanogens and members of the Korarchaeota were observed in vents from West Thumb and Elliot's Crater (pH 5–6). Conversely, metagenome sequence from Mary Bay vent sediments did not yield large assemblies, and contained diverse thermophilic and nonthermophilic bacterial relatives. Analysis of functional genes associated with the major vent populations indicated a direct linkage to high concentrations of carbon dioxide, reduced sulfur (sulfide and/or elemental S), hydrogen and methane in the deep thermal ecosystems. Our observations show that sublacustrine thermal vents in Yellowstone Lake support novel thermophilic communities, which contain microorganisms with functional attributes not found to date in terrestrial geothermal systems of YNP. PMID:26579074

Population Demographic History Can Cause the Appearance of Recombination Hotspots

PubMed Central

Johnston, Henry R.; Cutler, David J.

2012-01-01

Although the prevailing view among geneticists suggests that recombination hotspots exist ubiquitously across the human genome, there is only limited experimental evidence from a few genomic regions to support the generality of this claim. A small number of true recombination hotspots are well supported experimentally, but the vast majority of hotspots have been identified on the basis of population genetic inferences from the patterns of linkage disequilibrium (LD) seen in the human population. These inferences are made assuming a particular model of human history, and one of the assumptions of that model is that the effective population size of humans has remained constant throughout our history. Our results show that relaxation of the constant population size assumption can create LD and variation patterns that are qualitatively and quantitatively similar to human populations without any need to invoke localized hotspots of recombination. In other words, apparent recombination hotspots could be an artifact of variable population size over time. Several lines of evidence suggest that the vast majority of hotspots identified on the basis of LD information are unlikely to have elevated recombination rates. PMID:22560089

Amphibian mortality events and ranavirus outbreaks in the Greater Yellowstone Ecosystem

USGS Publications Warehouse

Patla, Debra A.; St-Hilaire, Sophia; Rayburn, Andrew P.; Hossack, Blake R.; Peterson, Charles R.

2016-01-01

Mortality events in wild amphibians go largely undocumented, and where events are detected, the numbers of dead amphibians observed are probably a small fraction of actual mortality (Green and Sherman 2001; Skerratt et al. 2007). Incidental observations from field surveys can, despite limitations, provide valuable information on the presence, host species, and spatial distribution of diseases. Here we summarize amphibian mortality events and diagnoses recorded from 2000 to 2014 in three management areas: Yellowstone National Park; Grand Teton National Park (including John D. Rockefeller, Jr. Memorial Parkway); and the National Elk Refuge, which together span a large portion of protected areas within the Greater Yellowstone Ecosystem (GYE; Noss et al. 2002). Our combined amphibian monitoring projects (e.g., Gould et al. 2012) surveyed an average of 240 wetlands per year over the 15 years. Field crews recorded amphibian mortalities during visual encounter and dip-netting surveys and collected moribund and dead specimens for diagnostic examinations. Amphibian and fish research projects during these years contributed additional mortality observations, specimens, and diagnoses.

Two-dimensional habitat modeling in the Yellowstone/Upper Missouri River system

USGS Publications Warehouse

Waddle, T. J.; Bovee, K.D.; Bowen, Z.H.

1997-01-01

This study is being conducted to provide the aquatic biology component of a decision support system being developed by the U.S. Bureau of Reclamation. In an attempt to capture the habitat needs of Great Plains fish communities we are looking beyond previous habitat modeling methods. Traditional habitat modeling approaches have relied on one-dimensional hydraulic models and lumped compositional habitat metrics to describe aquatic habitat. A broader range of habitat descriptors is available when both composition and configuration of habitats is considered. Habitat metrics that consider both composition and configuration can be adapted from terrestrial biology. These metrics are most conveniently accessed with spatially explicit descriptors of the physical variables driving habitat composition. Two-dimensional hydrodynamic models have advanced to the point that they may provide the spatially explicit description of physical parameters needed to address this problem. This paper reports progress to date on applying two-dimensional hydraulic and habitat models on the Yellowstone and Missouri Rivers and uses examples from the Yellowstone River to illustrate the configurational metrics as a new tool for assessing riverine habitats.

Estimating numbers of females with cubs-of-the-year in the Yellowstone grizzly bear population

USGS Publications Warehouse

Keating, K.A.; Schwartz, C.C.; Haroldson, M.A.; Moody, D.

2001-01-01

For grizzly bears (Ursus arctos horribilis) in the Greater Yellowstone Ecosystem (GYE), minimum population size and allowable numbers of human-caused mortalities have been calculated as a function of the number of unique females with cubs-of-the-year (FCUB) seen during a 3- year period. This approach underestimates the total number of FCUB, thereby biasing estimates of population size and sustainable mortality. Also, it does not permit calculation of valid confidence bounds. Many statistical methods can resolve or mitigate these problems, but there is no universal best method. Instead, relative performances of different methods can vary with population size, sample size, and degree of heterogeneity among sighting probabilities for individual animals. We compared 7 nonparametric estimators, using Monte Carlo techniques to assess performances over the range of sampling conditions deemed plausible for the Yellowstone population. Our goal was to estimate the number of FCUB present in the population each year. Our evaluation differed from previous comparisons of such estimators by including sample coverage methods and by treating individual sightings, rather than sample periods, as the sample unit. Consequently, our conclusions also differ from earlier studies. Recommendations regarding estimators and necessary sample sizes are presented, together with estimates of annual numbers of FCUB in the Yellowstone population with bootstrap confidence bounds.

Growth, morphology, and developmental instability of rainbow trout, Yellowstone cutthroat trout, and four hybrid generations

USGS Publications Warehouse

Ostberg, C.O.; Duda, J.J.; Graham, J.H.; Zhang, S.; Haywood, K. P.; Miller, B.; Lerud, T.L.

2011-01-01

Hybridization of cutthroat trout Oncorhynchus clarkii with nonindigenous rainbow trout O. mykiss contributes to the decline of cutthroat trout subspecies throughout their native range. Introgression by rainbow trout can swamp the gene pools of cutthroat trout populations, especially if there is little selection against hybrids. We used rainbow trout, Yellowstone cutthroat trout O. clarkii bouvieri, and rainbow trout × Yellowstone cutthroat trout F1 hybrids as parents to construct seven different line crosses: F1 hybrids (both reciprocal crosses), F2 hybrids, first-generation backcrosses (both rainbow trout and Yellowstone cutthroat trout), and both parental taxa. We compared growth, morphology, and developmental instability among these seven crosses reared at two different temperatures. Growth was related to the proportion of rainbow trout genome present within the crosses. Meristic traits were influenced by maternal, additive, dominant, overdominant, and (probably) epistatic genetic effects. Developmental stability, however, was not disturbed in F1 hybrids, F2 hybrids, or backcrosses. Backcrosses were morphologically similar to their recurrent parent. The lack of developmental instability in hybrids suggests that there are few genetic incompatibilities preventing introgression. Our findings suggest that hybrids are not equal: that is, growth, development, character traits, and morphology differ depending on the genomic contribution from each parental species as well as the hybrid generation.

Consumption of pondweed rhizomes by Yellowstone grizzly bears

USGS Publications Warehouse

Mattson, D.J.; Podruzny, S.R.; Haroldson, M.A.

2005-01-01

Pondweeds (Potamogeton spp.) are common foods of waterfowl throughout the Northern Hemisphere. However, consumption of pondweeds by bears has been noted only once, in Russia. We documented consumption of pondweed rhizomes by grizzly bears (Ursus arctos) in the Yellowstone region, 1977-96, during investigations of telemetry locations obtained from 175 radiomarked bears. We documented pondweed excavations at 25 sites and detected pondweed rhizomes in 18 feces. We observed grizzly bears excavating and consuming pondweed on 2 occasions. All excavations occurred in wetlands that were inundated during and after snowmelt, but dry by late August or early September of most years. These wetlands were typified by the presence of inflated sedge (Carex vesicaria) and occurred almost exclusively on plateaus of Pliocene-Pleistocene detrital sediments or volcanic rhyolite flows. Bears excavated wetlands with pondweeds when they were free of standing water, most commonly during October and occasionally during spring prior to the onset of terminal snowmelt. Most excavations were about 4.5 cm deep, 40 cubic decimeter (dm3) in total volume, and targeted the thickened pondweed rhizomes. Starch content of rhizomes collected near grizzly bear excavations averaged 28% (12% SD; n = 6). These results add to the documented diversity of grizzly bear food habits and, because pondweed is distributed circumboreally, also raise the possibility that consumption of pondweed by grizzly bears has been overlooked in other regions.

Dynamic placement of plasmonic hotspots for super-resolution surface-enhanced Raman scattering.

PubMed

Ertsgaard, Christopher T; McKoskey, Rachel M; Rich, Isabel S; Lindquist, Nathan C

2014-10-28

In this paper, we demonstrate dynamic placement of locally enhanced plasmonic fields using holographic laser illumination of a silver nanohole array. To visualize these focused "hotspots", the silver surface was coated with various biological samples for surface-enhanced Raman spectroscopy (SERS) imaging. Due to the large field enhancements, blinking behavior of the SERS hotspots was observed and processed using a stochastic optical reconstruction microscopy algorithm enabling super-resolution localization of the hotspots to within 10 nm. These hotspots were then shifted across the surface in subwavelength (<100 nm for a wavelength of 660 nm) steps using holographic illumination from a spatial light modulator. This created a dynamic imaging and sensing surface, whereas static illumination would only have produced stationary hotspots. Using this technique, we also show that such subwavelength shifting and localization of plasmonic hotspots has potential for imaging applications. Interestingly, illuminating the surface with randomly shifting SERS hotspots was sufficient to completely fill in a wide field of view for super-resolution chemical imaging.

Mountain Home Well - Photos

DOE Data Explorer

Shervais, John

2012-01-11

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. Data submitted by project collaborator Doug Schmitt, University of Alberta

Mountain Home Well - Borehole Geophysics Database

DOE Data Explorer

Shervais, John

2012-11-11

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. Data submitted by project collaborator Doug Schmitt, University of Alberta

Final evaluation report for the greater Yellowstone regional traveler and weather information system (GYRTWIS)

DOT National Transportation Integrated Search

2004-12-30

This final report describes the national evaluation of the Greater Yellowstone Regional Traveler and Weather Information System (GYRTWIS). This evaluation complements the ongoing GYRTWIS evaluation being conducted by WTI/MSU by investigating three ar...

Hotspot activity and plume pulses recorded by geometry of spreading axes

NASA Astrophysics Data System (ADS)

Abelson, Meir; Agnon, Amotz

2001-06-01

Anomalous plan view geometry (planform) of spreading axes is shown to be a faithful indicator of hotspot influence, possibly capable of detecting pulses of hotspot discharge. A planform anomaly (PA) occurs when the orientation of second-order ridge segments is prominently oblique to the spreading direction. PA is found in the vicinity of hotspots at shallow ridges (<1.5 km), suggesting hotspot influence. In places the PA and shallow bathymetry are accompanied by geochemical anomalies, corroborating hotspot influence. This linkage is best expressed in the western Gulf of Aden, where the extent of the PA from the Afar hotspot coincides with the extent of La/Sm and Sr isotopic anomalies. Using fracture mechanics we predict PA to reflect overpressurized melt that dominates the stresses in the crust, consistent with hotspot regime. Accordingly, the temporal variations of the planform previously inferred from magnetic anomalies around the Kolbeinsey Ridge (KR), north of Iceland, record episodes of interaction with the hotspot and major pulses of the plume. This suggestion is corroborated by temporal correlation of episodes showing PA north of Iceland with plume pulses previously inferred by the V-shaped ridges around the Reykjanes Ridge (RR), south of Iceland. In contrast to the RR, the temporal correlation suggests simultaneous incidence of the plume pulses at Iceland and KR, hundreds of kilometers to the north. A deep northward branch of the Iceland plume active during pulse-periods may explain these observations.

The proximity of hotspots to convergent and divergent plate boundaries

NASA Technical Reports Server (NTRS)

Weinstein, Stuart A.; Olson, Peter L.

1989-01-01

An analysis of four different hotspot distributions, ranging from Morgan's (1972) original list of 19 to Vogt's (1981) list of 117 reveals that the hotspots are preferentially located near divergent plate boundaries. The probability of this proximity occurring by chance alone is quite remote, less than 0.01 for all four hotspot distributions. The same analysis also reveals that the hotspots are preferentially excluded from regions near convergent plate boundaries. The probability of this exclusion occurring by chance alone is 0.1 or less for three out of the four distributions examined. We interpret this behavior as being a consequence of the effects of large scale convective circulation on ascending mantle plumes. Mantle thermal plumes, the most probable source of hotspots, arise from instabilities in a basal thermal boundary layer. Plumes are suppressed from regions beneath convergent boundaries by descending flow and are entrained into the upwelling flow beneath spreading centers. Plate-scale convective circulation driven by subduction may also advect mantle thermal plumes toward spreading centers.

Draft Genome Sequence of Bacillus altitudinis YNP4-TSU, Isolated from Yellowstone National Park

PubMed Central

OHair, Joshua A.; Li, Hui; Thapa, Santosh; Scholz, Matthew

2017-01-01

ABSTRACT Undisturbed hot springs inside Yellowstone National Park remain a dynamic biome for novel cellulolytic thermophiles. We report here the draft genome sequence of one of these isolates, Bacillus altitudinis YNP4-TSU. PMID:28705979

A fuzzy pattern matching method based on graph kernel for lithography hotspot detection

NASA Astrophysics Data System (ADS)

Nitta, Izumi; Kanazawa, Yuzi; Ishida, Tsutomu; Banno, Koji

2017-03-01

In advanced technology nodes, lithography hotspot detection has become one of the most significant issues in design for manufacturability. Recently, machine learning based lithography hotspot detection has been widely investigated, but it has trade-off between detection accuracy and false alarm. To apply machine learning based technique to the physical verification phase, designers require minimizing undetected hotspots to avoid yield degradation. They also need a ranking of similar known patterns with a detected hotspot to prioritize layout pattern to be corrected. To achieve high detection accuracy and to prioritize detected hotspots, we propose a novel lithography hotspot detection method using Delaunay triangulation and graph kernel based machine learning. Delaunay triangulation extracts features of hotspot patterns where polygons locate irregularly and closely one another, and graph kernel expresses inner structure of graphs. Additionally, our method provides similarity between two patterns and creates a list of similar training patterns with a detected hotspot. Experiments results on ICCAD 2012 benchmarks show that our method achieves high accuracy with allowable range of false alarm. We also show the ranking of the similar known patterns with a detected hotspot.

Response of Yellowstone grizzly bears to changes in food resources: A synthesis. Final report to the Interagency Grizzly Bear Committee and Yellowstone Ecosystem Subcommittee

USGS Publications Warehouse

,; van Manen, Frank T.; Costello, Cecily M.; Haroldson, Mark A.; Bjornlie, Daniel D.; Ebinger, Michael R.; Gunther, Kerry A.; Mahalovich, Mary Frances; Thompson, Daniel J.; Higgs, Megan D.; Irvine, Kathryn M.; Legg, Kristin; Tyers, Daniel B.; Landenburger, Lisa; Cain, Steven L.; Frey, Kevin L.; Aber, Bryan C.; Schwartz, Charles C.

2013-01-01

The Yellowstone grizzly bear (Ursus arctos) was listed as a threatened species in 1975 (Federal Register 40 FR:31734-31736). Since listing, recovery efforts have focused on increasing population size, improving habitat security, managing bear mortalities, and reducing bear-human conflicts. The Interagency Grizzly Bear Committee (IGBC; partnership of federal and state agencies responsible for grizzly bear recovery in the lower 48 states) and its Yellowstone Ecosystem Subcommitte (YES; federal, state, county, and tribal partners charged with recovery of grizzly bears in the Greater Yelowston Ecosystem [GYE]) tasked the Interagency Grizzly Bear Study Team to provide information and further research relevant to three concerns arising from the 9th Circuit Court of Appeals November 2011 decision: 1) the ability of grizzly bears as omnivores to find alternative foods to whitebark pine seeds; 2) literature to support their conclusions; and 3) the non-intuitive biological reality that impacts can occur to individuals without causing the overall population to decline. Specifically, the IGBC and YES requested a comprehensive synthesis of the current state of knowledge regarding whitebark pinbe decline and individual and population-level responses of grizzly bears to changing food resources in the GYE. This research was particularly relevant to grizzly bear conservation given changes in the population trajectory observed during the last decade.

Are hotspots always hotspots? The relationship between diversity, resource and ecosystem functions in the Arctic.

PubMed

Link, Heike; Piepenburg, Dieter; Archambault, Philippe

2013-01-01

The diversity-ecosystem function relationship is an important topic in ecology but has not received much attention in Arctic environments, and has rarely been tested for its stability in time. We studied the temporal variability of benthic ecosystem functioning at hotspots (sites with high benthic boundary fluxes) and coldspots (sites with lower fluxes) across two years in the Canadian Arctic. Benthic remineralisation function was measured as fluxes of oxygen, silicic acid, phosphate, nitrate and nitrite at the sediment-water interface. In addition we determined sediment pigment concentration and taxonomic and functional macrobenthic diversity. To separate temporal from spatial variability, we sampled the same nine sites from the Mackenzie Shelf to Baffin Bay during the same season (summer or fall) in 2008 and 2009. We observed that temporal variability of benthic remineralisation function at hotspots is higher than at coldspots and that taxonomic and functional macrobenthic diversity did not change significantly between years. Temporal variability of food availability (i.e., sediment surface pigment concentration) seemed higher at coldspot than at hotspot areas. Sediment chlorophyll a (Chl a) concentration, taxonomic richness, total abundance, water depth and abundance of the largest gallery-burrowing polychaete Lumbrineristetraura together explained 42% of the total variation in fluxes. Food supply proxies (i.e., sediment Chl a and depth) split hot- from coldspot stations and explained variation on the axis of temporal variability, and macrofaunal community parameters explained variation mostly along the axis separating eastern from western sites with hot- or coldspot regimes. We conclude that variability in benthic remineralisation function, food supply and diversity will react to climate change on different time scales, and that their interactive effects may hide the detection of progressive change, particularly at hotspots. Time-series of benthic functions and

Effects of Demographic History on the Detection of Recombination Hotspots from Linkage Disequilibrium.

PubMed

Dapper, Amy L; Payseur, Bret A

2018-02-01

In some species, meiotic recombination is concentrated in small genomic regions. These "recombination hotspots" leave signatures in fine-scale patterns of linkage disequilibrium, raising the prospect that the genomic landscape of hotspots can be characterized from sequence variation. This approach has led to the inference that hotspots evolve rapidly in some species, but are conserved in others. Historic demographic events, such as population bottlenecks, are known to affect patterns of linkage disequilibrium across the genome, violating population genetic assumptions of this approach. Although such events are prevalent, demographic history is generally ignored when making inferences about the evolution of recombination hotspots. To determine the effect of demography on the detection of recombination hotspots, we use the coalescent to simulate haplotypes with a known recombination landscape. We measure the ability of popular linkage disequilibrium-based programs to detect hotspots across a range of demographic histories, including population bottlenecks, hidden population structure, population expansions, and population contractions. We find that demographic events have the potential to greatly reduce the power and increase the false positive rate of hotspot discovery. Neither the power nor the false positive rate of hotspot detection can be predicted without also knowing the demographic history of the sample. Our results suggest that ignoring demographic history likely overestimates the power to detect hotspots and therefore underestimates the degree of hotspot sharing between species. We suggest strategies for incorporating demographic history into population genetic inferences about recombination hotspots. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Performance of Yellowstone and Snake River Cutthroat Trout Fry Fed Seven Different Diets.

USDA-ARS?s Scientific Manuscript database

Five commercial diets and two formulated feeds were fed to initial-feeding Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri fry and Snake River cutthroat trout O. clarkii spp. (currently being petitioned for classification as O. clarkii behnkei) fry for 18 weeks to evaluate fish performance...

78 FR 12353 - Winter Use Plan, Supplemental Environmental Impact Statement, Yellowstone National Park

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-22

... DEPARTMENT OF THE INTERIOR National Park Service [NPS-IMR-YELL-12081; PPWONRADE2, PMP00EI05.YP0000] Winter Use Plan, Supplemental Environmental Impact Statement, Yellowstone National Park AGENCY: National Park Service, Interior. ACTION: Notice of Availability. SUMMARY: Pursuant to the National Environmental...

Classification of reaches in the Missouri and lower Yellowstone Rivers based on flow characteristics

USGS Publications Warehouse

Pegg, Mark A.; Pierce, Clay L.

2002-01-01

Several aspects of flow have been shown to be important determinants of biological community structure and function in streams, yet direct application of this approach to large rivers has been limited. Using a multivariate approach, we grouped flow gauges into hydrologically similar units in the Missouri and lower Yellowstone Rivers and developed a model based on flow variability parameters that could be used to test hypotheses about the role of flow in determining aquatic community structure. This model could also be used for future comparisons as the hydrological regime changes. A suite of hydrological parameters for the recent, post-impoundment period (1 October 1966–30 September 1996) for each of 15 gauges along the Missouri and lower Yellowstone Rivers were initially used. Preliminary graphical exploration identified five variables for use in further multivariate analyses. Six hydrologically distinct units composed of gauges exhibiting similar flow characteristics were then identified using cluster analysis. Discriminant analyses identified the three most influential variables as flow per unit drainage area, coefficient of variation of mean annual flow, and flow constancy. One surprising result was the relative similarity of flow regimes between the two uppermost and three lowermost gauges, despite large differences in magnitude of flow and separation by roughly 3000 km. Our results synthesize, simplify and interpret the complex changes in flow occurring along the Missouri and lower Yellowstone Rivers, and provide an objective grouping for future tests of how these changes may affect biological communities. 

Effects of Demographic History on the Detection of Recombination Hotspots from Linkage Disequilibrium

PubMed Central

Dapper, Amy L; Payseur, Bret A

2018-01-01

Abstract In some species, meiotic recombination is concentrated in small genomic regions. These “recombination hotspots” leave signatures in fine-scale patterns of linkage disequilibrium, raising the prospect that the genomic landscape of hotspots can be characterized from sequence variation. This approach has led to the inference that hotspots evolve rapidly in some species, but are conserved in others. Historic demographic events, such as population bottlenecks, are known to affect patterns of linkage disequilibrium across the genome, violating population genetic assumptions of this approach. Although such events are prevalent, demographic history is generally ignored when making inferences about the evolution of recombination hotspots. To determine the effect of demography on the detection of recombination hotspots, we use the coalescent to simulate haplotypes with a known recombination landscape. We measure the ability of popular linkage disequilibrium-based programs to detect hotspots across a range of demographic histories, including population bottlenecks, hidden population structure, population expansions, and population contractions. We find that demographic events have the potential to greatly reduce the power and increase the false positive rate of hotspot discovery. Neither the power nor the false positive rate of hotspot detection can be predicted without also knowing the demographic history of the sample. Our results suggest that ignoring demographic history likely overestimates the power to detect hotspots and therefore underestimates the degree of hotspot sharing between species. We suggest strategies for incorporating demographic history into population genetic inferences about recombination hotspots. PMID:29045724

Monitoring Greater Yellowstone Ecosystem wetlands: Can long-term monitoring help us understand their future?

USGS Publications Warehouse

Ray, Andrew M.; Sepulveda, Adam; Hossack, Blake R.; Patla, Debra; Thoma, David; Al-Chokhachy, Robert K.; Litt, Andrea R.

2015-01-01

In the Greater Yellowstone Ecosystem (GYE), changes in the drying cycles of wetlands have been documented. Wetlands are areas where the water table is at or near the land surface and standing shallow water is present for much or all of the growing season. We discuss how monitoring data can be used to document variation in annual flooding and drying patterns of wetlands monitored across Yellowstone and Grand Teton national parks, investigate how these patterns are related to a changing climate, and explore how drying of wetlands may impact amphibians. The documented declines of some amphibian species are of growing concern to scientists and land managers alike, in part because disappearances have occurred in some of the most protected places. These disappearances are a recognized component of what is being described as Earth’s sixth mass extinction.

Distribution, congruence, and hotspots of higher plants in China

PubMed Central

Zhao, Lina; Li, Jinya; Liu, Huiyuan; Qin, Haining

2016-01-01

Identifying biodiversity hotspots has become a central issue in setting up priority protection areas, especially as financial resources for biological diversity conservation are limited. Taking China’s Higher Plants Red List (CHPRL), including Bryophytes, Ferns, Gymnosperms, Angiosperms, as the data source, we analyzed the geographic patterns of species richness, endemism, and endangerment via data processing at a fine grid-scale with an average edge length of 30 km based on three aspects of richness information: species richness, endemic species richness, and threatened species richness. We sought to test the accuracy of hotspots used in identifying conservation priorities with regard to higher plants. Next, we tested the congruence of the three aspects and made a comparison of the similarities and differences between the hotspots described in this paper and those in previous studies. We found that over 90% of threatened species in China are concentrated. While a high spatial congruence is observed among the three measures, there is a low congruence between two different sets of hotspots. Our results suggest that biodiversity information should be considered when identifying biological hotspots. Other factors, such as scales, should be included as well to develop biodiversity conservation plans in accordance with the region’s specific conditions. PMID:26750244

Distribution, congruence, and hotspots of higher plants in China.

PubMed

Zhao, Lina; Li, Jinya; Liu, Huiyuan; Qin, Haining

2016-01-11

Identifying biodiversity hotspots has become a central issue in setting up priority protection areas, especially as financial resources for biological diversity conservation are limited. Taking China's Higher Plants Red List (CHPRL), including Bryophytes, Ferns, Gymnosperms, Angiosperms, as the data source, we analyzed the geographic patterns of species richness, endemism, and endangerment via data processing at a fine grid-scale with an average edge length of 30 km based on three aspects of richness information: species richness, endemic species richness, and threatened species richness. We sought to test the accuracy of hotspots used in identifying conservation priorities with regard to higher plants. Next, we tested the congruence of the three aspects and made a comparison of the similarities and differences between the hotspots described in this paper and those in previous studies. We found that over 90% of threatened species in China are concentrated. While a high spatial congruence is observed among the three measures, there is a low congruence between two different sets of hotspots. Our results suggest that biodiversity information should be considered when identifying biological hotspots. Other factors, such as scales, should be included as well to develop biodiversity conservation plans in accordance with the region's specific conditions.

Spatial analysis to identify hotspots of prevalence of schizophrenia.

PubMed

Moreno, Berta; García-Alonso, Carlos R; Negrín Hernández, Miguel A; Torres-González, Francisco; Salvador-Carulla, Luis

2008-10-01

The geographical distribution of mental health disorders is useful information for epidemiological research and health services planning. To determine the existence of geographical hotspots with a high prevalence of schizophrenia in a mental health area in Spain. The study included 774 patients with schizophrenia who were users of the community mental health care service in the area of South Granada. Spatial analysis (Kernel estimation) and Bayesian relative risks were used to locate potential hotspots. Availability and accessibility were both rated in each zone and spatial algebra was applied to identify hotspots in a particular zone. The age-corrected prevalence rate of schizophrenia was 2.86 per 1,000 population in the South Granada area. Bayesian analysis showed a relative risk varying from 0.43 to 2.33. The area analysed had a non-uniform spatial distribution of schizophrenia, with one main hotspot (zone S2). This zone had poor accessibility to and availability of mental health services. A municipality-based variation exists in the prevalence of schizophrenia and related disorders in the study area. Spatial analysis techniques are useful tools to analyse the heterogeneous distribution of a variable and to explain genetic/environmental factors in hotspots related with a lack of easy availability of and accessibility to adequate health care services.

A Method for Improving Hotspot Directional Signatures in BRDF Models Used for MODIS

NASA Technical Reports Server (NTRS)

Jiao, Ziti; Schaaf, Crystal B.; Dong, Yadong; Roman, Miguel; Hill, Michael J.; Chen, Jing M.; Wang, Zhuosen; Zhang, Hu; Saenz, Edward; Poudyal, Rajesh;

Protecting the Geyser Basins of Yellowstone National Park: Toward a New National Policy for a Vulnerable Environmental Resource

NASA Astrophysics Data System (ADS)

Barrick, Kenneth A.

2010-01-01

Geyser basins provide high value recreation, scientific, economic and national heritage benefits. Geysers are globally rare, in part, because development activities have quenched about 260 of the natural endowment. Today, more than half of the world’s remaining geysers are located in Yellowstone National Park, northwest Wyoming, USA. However, the hydrothermal reservoirs that supply Yellowstone’s geysers extend well beyond the Park borders, and onto two “Known Geothermal Resource Areas”—Island Park to the west and Corwin Springs on the north. Geysers are sensitive geologic features that are easily quenched by nearby geothermal wells. Therefore, the potential for geothermal energy development adjacent to Yellowstone poses a threat to the sustainability of about 500 geysers and 10,000 hydrothermal features. The purpose here is to propose that Yellowstone be protected by a “Geyser Protection Area” (GPA) extending in a 120-km radius from Old Faithful Geyser. The GPA concept would prohibit geothermal and large-scale groundwater wells, and thereby protect the water and heat supply of the hydrothermal reservoirs that support Yellowstone’s geyser basins and important hot springs. Proactive federal leadership, including buyouts of private groundwater development rights, can assist in navigating the GPA through the greater Yellowstone area’s “wicked” public policy environment. Moreover, the potential impacts on geyser basins from intrusive research sampling techniques are considered in order to facilitate the updating of national park research regulations to a precautionary standard. The GPA model can provide the basis for protecting the world’s few remaining geyser basins.

Use of naturally occurring mercury to determine the importance of cutthroat trout to Yellowstone grizzly bears

USGS Publications Warehouse

Felicetti, L.A.; Schwartz, C.C.; Rye, R.O.; Gunther, K.A.; Crock, J.G.; Haroldson, M.A.; Waits, L.; Robbins, C.T.

2004-01-01

Spawning cutthroat trout (Oncorhynchus clarki (Richardson, 1836)) are a potentially important food resource for grizzly bears (Ursus arctos horribilis Ord, 1815) in the Greater Yellowstone Ecosystem. We developed a method to estimate the amount of cutthroat trout ingested by grizzly bears living in the Yellowstone Lake area. The method utilized (i) the relatively high, naturally occurring concentration of mercury in Yellowstone Lake cutthroat trout (508 ± 93 ppb) and its virtual absence in all other bear foods (6 ppb), (ii) hair snares to remotely collect hair from bears visiting spawning cutthroat trout streams between 1997 and 2000, (iii) DNA analyses to identify the individual and sex of grizzly bears leaving a hair sample, (iv) feeding trials with captive bears to develop relationships between fish and mercury intake and hair mercury concentrations, and (v) mercury analyses of hair collected from wild bears to estimate the amount of trout consumed by each bear. Male grizzly bears consumed an average of 5 times more trout/kg bear than did female grizzly bears. Estimated cutthroat trout intake per year by the grizzly bear population was only a small fraction of that estimated by previous investigators, and males consumed 92% of all trout ingested by grizzly bears.

Hotspot relaxation dynamics in a current-carrying superconductor

NASA Astrophysics Data System (ADS)

Marsili, F.; Stevens, M. J.; Kozorezov, A.; Verma, V. B.; Lambert, Colin; Stern, J. A.; Horansky, R. D.; Dyer, S.; Duff, S.; Pappas, D. P.; Lita, A. E.; Shaw, M. D.; Mirin, R. P.; Nam, S. W.

2016-03-01

We experimentally studied the dynamics of optically excited hotspots in current-carrying WSi superconducting nanowires as a function of bias current, bath temperature, and excitation wavelength. We observed that the hotspot relaxation time depends on bias current, temperature, and wavelength. We explained this effect with a model based on quasiparticle recombination, which provides insight into the quasiparticle dynamics of superconductors.

Vegetation Cover Change in Yellowstone National Park Detected Using Landsat Satellite Image Analysis

NASA Technical Reports Server (NTRS)

Potter, Christopher S.

2015-01-01

Results from Landsat satellite image analysis since 1987 in all unburned areas (since the 1880s) of Yellowstone National Park (YNP) showed that consistent decreases in the normalized difference vegetation index (NDVI) have been strongly dependent on periodic variations in peak annual snow water equivalents (SWE).

Fire, Death, and Rebirth: A Metaphoric Analysis of the 1988 Yellowstone Fire Debate.

ERIC Educational Resources Information Center

Hardy-Short, Dayle C.; Short, C. Brant

1995-01-01

Finds that two primary archetypal metaphors--death and rebirth--emerged in the public debate concerning management of the 1988 Yellowstone forest fires. Argues that the crisis brought two competing views of public land management to the forefront: the ecological view, and the human-centered view. (SR)

Database for the geologic map of Upper Geyser Basin, Yellowstone National Park, Wyoming

USGS Publications Warehouse

Abendini, Atosa A.; Robinson, Joel E.; Muffler, L. J. Patrick; White, D. E.; Beeson, Melvin H.; Truesdell, A. H.

2015-01-01

This dataset contains contacts, geologic units, and map boundaries from Miscellaneous Investigations Series Map I-1371, "The Geologic map of upper Geyser Basin, Yellowstone, National Park, Wyoming". This dataset was constructed to produce a digital geologic map as a basis for ongoing studies of hydrothermal processes.

The Manihiki Plateau—a key to missing hotspot tracks?

NASA Astrophysics Data System (ADS)

Pietsch, R.; Uenzelmann-Neben, G.

2016-08-01

A Neogene magmatic reactivation of the Manihiki Plateau, a large igneous province (LIP) in the central Pacific, is studied using seismic reflection data. Igneous diapirs have been identified exclusively within a narrow WNW-ESE striking corridor in the southern High Plateau (HP), which is parallel to the Neogene Pacific Plate motion and overlaps with an extrapolation of the Society Islands Hotspot (SIH) path. The igneous diapirs are characterized by a narrow width (>5 km), penetration of the Neogene sediments, and they become progressively younger towards the East (23-10 Ma). The magmatic source appears to be of small lateral extent, which leads to the conclusion that the diapirs represent Neogene hotspot volcanism within a LIP, and thus may be an older, previously unknown extension of the SIH track (>4.5 Ma). Comparing hotspot volcanism within oceanic and continental lithosphere, we further conclude that hotspot volcanism within LIP crust has similarities to tectonically faulted continental crust.

Arsenic and antimony in geothermal waters of Yellowstone National Park, Wyoming, USA

USGS Publications Warehouse

Stauffer, R.E.; Thompson, J.M.

1984-01-01

A total of 268 thermal spring samples were analyzed for total soluble As using reduced molybdenum-blue; 27 of these samples were also analyzed for total Sb using flame atomic absorption spectrometry. At Yellowstone the Cl As atomic ratio is nearly constant among neutral-alkaline springs with Cl > 100 mg L-1, and within restricted geographic areas, indicating no differential effects of adiabatic vs. conductive cooling on arsenic. The Cl As ratio increases with silica and decreases with decreasing Cl ??CO3; the latter relationship is best exemplified for springs along the extensively sampled SE-NW trend within the Lone Star-Upper-Midway Basin region. The relationship between Cl As and Cl ??CO3 at Yellowstone suggests a possible rock leaching rather than magmatic origin for much of the Park's total As flux. Condensed vapor springs are low in both As and Cl. Very high Cl As ratios ( > 1000) are associated exclusively with highly diluted (Cl < 100 mg L-1) mixed springs in the Norris and Shoshone Basins and in the Upper White Creek and Firehole Lake areas of Lower Basin. The high ratios are associated with acidity and/or oxygen and iron; they indicate precipitation of As following massive dilution of the Asbearing high-Cl parent water. Yellowstone Sb ranged from 0.009 at Mammoth to 0.166 mg L-1 at Joseph's Coat Spring. Within basins, the Cl Sb ratio increases as the Cl ??CO3 ratio decreases, in marked contrast to As. Mixed springs also have elevated Cl Sb ratios. White (1967) and Weissberg (1969) previously reported stibnite (Sb2S3), but not orpiment (As2S3), precipitating in the near surface zone of alkaline geothermal systems. ?? 1984.

Environmental setting of the Yellowstone River basin, Montana, North Dakota, and Wyoming

USGS Publications Warehouse

Zelt, Ronald B.; Boughton, G.K.; Miller, K.A.; Mason, J.P.; Gianakos, L.M.

1999-01-01

Natural and anthropogenic factors influence water-quality conditions in the Yellowstone River Basin. Physiography parallels the structural geologic setting that is generally composed of several uplifts and structural basins. Contrasts in climate and vegetation reflect topographic controls and the midcontinental location of the study unit. Surface-water hydrology reflects water surpluses in mountainous areas that are dominated by snowmelt runoff, and arid to semiarid conditions in the plains that are dissected by typically irrigated valleys in the remainder of the study unit. Principal shallow aquifers are Tertiary sandstones and unconsolidated Quaternary deposits. Human population, though sparsely distributed in general, is growing most rapidly in a few urban centers and resort areas, mostly in the northwestern part of the basin. Land use is areally dominated by grazing in the basins and plains and economically dominated by mineral-extraction activities. Forests are the dominant land cover in mountainous areas. Cropland is a major land use in principal stream valleys. Water use is dominated by irrigated agriculture overall, but mining and public-supply facilities are major users of ground water. Coal and hydrocarbon production and reserves distinguish the Yellowstone River Basin as a principal energy-minerals resources region. Current metallic ore production or reserves are nationally significant for platinum-group elements and chromium.The study unit was subdivided as an initial environmental stratification for use in designing the National Water-Quality Assessment Program investigation that began in 1997. Ecoregions, geologic groups, mineral-resource areas, and general land-cover and land-use categories were used in combination to define 18 environmental settings in the Yellowstone River Basin. It is expected that these different settings will be reflected in differing water-quality or aquatic-ecological characteristics.

Water chemistry and electrical conductivity database for rivers in Yellowstone National Park, Wyoming

USGS Publications Warehouse

Clor, Laura E.; McCleskey, R. Blaine; Huebner, Mark A.; Lowenstern, Jacob B.; Heasler, Henry P.; Mahony, Dan L.; Maloney, Tim; Evans, William C.

2012-01-01

This study aims to quantify relations between solute concentrations (especially chloride) and electrical conductivity for several rivers in Yellowstone National Park (YNP), by using automated samplers and conductivity meters. Norton and Friedman (1985) found that chloride concentrations and electrical conductivity have a good correlation in the Falls, Snake, Madison, and Yellowstone Rivers. However, their results are based on limited sampling and hydrologic conditions and their relation with other solutes was not determined. Once the correlations are established, conductivity measurements can then be used as a proxy for chloride concentrations, thereby enabling continuous heat-flow estimation on a much finer timescale and at lower cost than is currently possible with direct sampling. This publication serves as a repository for all data collected during the course of the study from May 2010 through July 2011, but it does not include correlations between solutes and conductivity or recommendations for quantification of chloride through continuous electrical conductivity measurements. This will be the object of a future document.

Predatory behavior of grizzly bears feeding on elk calves in Yellowstone National Park

USGS Publications Warehouse

French, Steven P.; French, Marilynn G.

1990-01-01

Grizzly bears (Ursus arctos horribilis) were observed preying on elk calves (Cervus elaphus) on 60 occasions in Yellowstone National Park, with 29 confirmed kills. Some bears were deliberate predators and effectively preyed on elk calves for short periods each spring, killing up to 1 calf daily. Primary hunting techniques were searching and chasing although some bears used a variety of techniques during a single hunt. They hunted both day and night and preyed on calves in the open and in the woods. Excess killing occurred when circumstances permitted. One bear caught 5 calves in a 15-minute interval. Elk used a variety of antipredator defenses and occasionally attacked predacious bears. The current level of this feeding behavior appears to be greater than previously reported. This is probably related to the increased availability of calves providing a greater opportunity for learning, and the adaptation of a more predatory behavior by some grizzly bears in Yellowstone.

Modeling sound due to over-snow vehicles in Yellowstone and Grand Teton National Parks

DOT National Transportation Integrated Search

2006-10-01

A modified version of the FAAs Integrated Noise Model (INM) Version 6.2 was used to : model the sound of over-snow vehicles (OSVs) (snowmobiles and snowcoaches) in : Yellowstone and Grand Teton National Parks for ten modeling scenarios provided by...

Detecting Recombination Hotspots from Patterns of Linkage Disequilibrium.

PubMed

Wall, Jeffrey D; Stevison, Laurie S

2016-08-09

With recent advances in DNA sequencing technologies, it has become increasingly easy to use whole-genome sequencing of unrelated individuals to assay patterns of linkage disequilibrium (LD) across the genome. One type of analysis that is commonly performed is to estimate local recombination rates and identify recombination hotspots from patterns of LD. One method for detecting recombination hotspots, LDhot, has been used in a handful of species to further our understanding of the basic biology of recombination. For the most part, the effectiveness of this method (e.g., power and false positive rate) is unknown. In this study, we run extensive simulations to compare the effectiveness of three different implementations of LDhot. We find large differences in the power and false positive rates of these different approaches, as well as a strong sensitivity to the window size used (with smaller window sizes leading to more accurate estimation of hotspot locations). We also compared our LDhot simulation results with comparable simulation results obtained from a Bayesian maximum-likelihood approach for identifying hotspots. Surprisingly, we found that the latter computationally intensive approach had substantially lower power over the parameter values considered in our simulations. Copyright © 2016 Wall and Stevison.

Phase II (baseline) report for the Greater Yellowstone Regional Traveler and Weather Information System (GYRTWIS)

DOT National Transportation Integrated Search

2002-09-11

In an effort to make road and weather information more readily available to travelers and maintenance personnel, Montana is implementing the Greater Yellowstone Regional Traveler and Weather Information System (GYRTWIS). GYRTWIS replaces the existing...

Plumbing the depths of Yellowstone's hydrothermal system from helicopter magnetic and electromagnetic data

NASA Astrophysics Data System (ADS)

Finn, C.; Bedrosian, P.; Holbrook, W. S.; Auken, E.; Lowenstern, J. B.; Hurwitz, S.; Sims, K. W. W.; Carr, B.; Dickey, K.

2017-12-01

Although Yellowstone's iconic hydrothermal systems and lava flows are well mapped at the surface, their groundwater flow systems and thickness are almost completely unknown. In order to track the geophysical signatures of geysers, hot springs, mud pots, steam vents, hydrothermal explosion craters and lava flows at depths to hundreds of meters, we collected helicopter electromagnetic and magnetic (HEM) data. The data cover significant portions of the caldera including a majority of the known thermal areas. HEM data constrain electrical resistivity which is sensitive to groundwater salinity and temperature, phase distribution (liquid-vapor), and clay formed during chemical alteration of rocks. The magnetic data are sensitive to variations in the magnetization of lava flows, faults and hydrothermal alteration. The combination of electromagnetic and magnetic data is ideal for mapping zones of cold fresh water, hot saline water, steam, clay, and altered and unaltered rock. Preliminary inversion of the HEM data indicates very low resistivity directly beneath the northern part of Yellowstone Lake, intersecting with the lake bottom in close correspondence with mapped vents, fractures and hydrothermal explosion craters and are also associated with magnetic lows. Coincident resistivity and magnetic lows unassociated with mapped alteration occur, for example, along the southeast edge of the Mallard Lake dome and along the northeastern edge of Sour Creek Dome, suggesting the presence of buried alteration. Low resistivities unassociated with magnetic lows may relate to hot and/or saline groundwater or thin (<50 m) layers of early lake sediments to which the magnetic data are insensitive. Resistivity and magnetic lows follow interpreted caldera boundaries in places, yet deviate in others. In the Norris-Mammoth Corridor, NNE-SSW trending linear resistivity and magnetic lows align with mapped faults. This pattern of coincident resistivity and magnetic lows may reflect fractures

Detecting Malaria Hotspots: A Comparison of Rapid Diagnostic Test, Microscopy, and Polymerase Chain Reaction

PubMed Central

Mogeni, Polycarp; Williams, Thomas N; Omedo, Irene; Kimani, Domtila; Ngoi, Joyce M; Mwacharo, Jedida; Morter, Richard; Nyundo, Christopher; Wambua, Juliana; Nyangweso, George; Kapulu, Melissa; Fegan, Gregory; Bejon, Philip

2017-01-01

Abstract Background Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. Methods We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Results Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Conclusion Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls. PMID:28973672

Kimberly Well - Photos

DOE Data Explorer

Shervais, John

2011-06-16

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Kimberly drill hole was selected to document continuous volcanism when analysed in conjunction with the Kimama and is located near the margin of the plain. Data submitted by project collaborator Doug Schmitt, University of Alberta

Kimberly Well - Borehole Geophysics Database

DOE Data Explorer

Shervais, John

2011-07-04

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Kimberly drill hole was selected to document continuous volcanism when analysed in conjunction with the Kimama and is located near the margin of the plain. Data submitted by project collaborator Doug Schmitt, University of Alberta

Quartz phenocrysts preserve volcanic stresses at Long Valley and Yellowstone calderas

NASA Astrophysics Data System (ADS)

Befus, K. S.; Leonhardi, T. C.; Manga, M.; Tamura, N.; Stan, C. V.

2016-12-01

Magmatic processes and eruptions are the consequence of stresses active in volcanic environments. Few techniques are presently available to quantify those stresses because they operate in subsurface and/or hazardous environments, and thus new techniques are needed to advance our understanding of key processes. Here, we provide a dataset of volcanic stresses that were imparted to quartz crystals that traveled through, and were hosted within, pyroclastic and effusive eruptions from Long Valley and Yellowstone calderas. We measured crystal lattice deformation with submicron spatial resolution using the synchrotron X-ray microdiffraction beamline (12.3.2) at the Advanced Light Source, Lawrence Berkeley National Laboratory. Quartz from all units produces diffraction patterns with residual strains locked in the crystal lattice. We used Hooke's Law and the stiffness constants of quartz to calculate the stresses that caused the preserved residual strains. At Long Valley caldera, quartz preserves stresses of 187±80 MPa within pumice clasts in the F1 fall unit of the Bishop Tuff, and preserves stresses of 120±45 MPa from the Bishop Tuff welded ignimbrite. At Yellowstone caldera quartz preserves stresses of 115±30 and 140±60 MPa within pumices from the basal fall units of the Mesa Falls Tuff and the Tuff of Bluff Point, respectively. Quartz from near-vent and flow-front samples from Summit Lake lava flow preserves stresses up to 130 MPa, and show no variation with distance travelled. We believe that subsurface processes cause the measured residual stresses, but it remains unclear if they are relicts of fragmentation or from the magma chamber. The residual stresses from both Long Valley and Yellowstone samples roughly correlate to lithostatic pressures estimated for the respective pre-eruption magma storage depths. It is possible that residual stress in quartz provides a new geobarometer for crystallization pressure. Moving forward, we will continue to perform analyses and

A Full Snow Season in Yellowstone: A Database of Restored Aqua Band 6

NASA Technical Reports Server (NTRS)

Gladkova, Irina; Grossberg, Michael; Bonev, George; Romanov, Peter; Riggs, George; Hall, Dorothy

2013-01-01

The algorithms for estimating snow extent for the Moderate Resolution Imaging Spectroradiometer (MODIS) optimally use the 1.6- m channel which is unavailable for MODIS on Aqua due to detector damage. As a test bed to demonstrate that Aqua band 6 can be restored, we chose the area surrounding Yellowstone and Grand Teton national parks. In such rugged and difficult-to-access terrain, satellite images are particularly important for providing an estimation of snow-cover extent. For the full 2010-2011 snow season covering the Yellowstone region, we have used quantitative image restoration to create a database of restored Aqua band 6. The database includes restored radiances, normalized vegetation index, normalized snow index, thermal data, and band-6-based snow-map products. The restored Aqua-band-6 data have also been regridded and combined with Terra data to produce a snow-cover map that utilizes both Terra and Aqua snow maps. Using this database, we show that the restored Aqua-band-6-based snow-cover extent has a comparable performance with respect to ground stations to the one based on Terra. The result of a restored band 6 from Aqua is that we have an additional band-6 image of the Yellowstone region each day. This image can be used to mitigate cloud occlusion, using the same algorithms used for band 6 on Terra. We show an application of this database of restored band-6 images to illustrate the value of creating a cloud gap filling using the National Aeronautics and Space Administration s operational cloud masks and data from both Aqua and Terra.

Opioid and orexin hedonic hotspots in rat orbitofrontal cortex and insula

PubMed Central

Castro, Daniel C.; Berridge, Kent C.

2017-01-01

Hedonic hotspots are brain sites where particular neurochemical stimulations causally amplify the hedonic impact of sensory rewards, such as “liking” for sweetness. Here, we report the mapping of two hedonic hotspots in cortex, where mu opioid or orexin stimulations enhance the hedonic impact of sucrose taste. One hedonic hotspot was found in anterior orbitofrontal cortex (OFC), and another was found in posterior insula. A suppressive hedonic coldspot was also found in the form of an intervening strip stretching from the posterior OFC through the anterior and middle insula, bracketed by the two cortical hotspots. Opioid/orexin stimulations in either cortical hotspot activated Fos throughout a distributed “hedonic circuit” involving cortical and subcortical structures. Conversely, cortical coldspot stimulation activated circuitry for “hedonic suppression.” Finally, food intake was increased by stimulations at several prefrontal cortical sites, indicating that the anatomical substrates in cortex for enhancing the motivation to eat are discriminable from those for hedonic impact. PMID:29073109

Tree-ring 14C links seismic swarm to CO2 spike at Yellowstone, USA

USGS Publications Warehouse

Evans, William C.; Bergfeld, D.; McGeehin, J.P.; King, J.C.; Heasler, H.

2010-01-01

Mechanisms to explain swarms of shallow seismicity and inflation-deflation cycles at Yellowstone caldera (western United States) commonly invoke episodic escape of magma-derived brines or gases from the ductile zone, but no correlative changes in the surface efflux of magmatic constituents have ever been documented. Our analysis of individual growth rings in a tree core from the Mud Volcano thermal area within the caldera links a sharp ~25% drop in 14C to a local seismic swarm in 1978. The implied fivefold increase in CO2 emissions clearly associates swarm seismicity with upflow of magma-derived fluid and shows that pulses of magmatic CO2 can rapidly traverse the 5-kmthick brittle zone, even through Yellowstone's enormous hydrothermal reservoir. The 1978 event predates annual deformation surveys, but recognized connections between subsequent seismic swarms and changes in deformation suggest that CO2 might drive both processes. ?? 2010 Geological Society of America.

Chemical analyses of hot springs, pools, geysers, and surface waters from Yellowstone National Park, Wyoming, and vicinity, 1974-1975

USGS Publications Warehouse

Ball, James W.; Nordstrom, D. Kirk; Jenne, Everett A.; Vivit, Davison V.

1998-01-01

This report presents all analytical determinations for samples collected from Yellowstone National Park and vicinity during 1974 and 1975. Water temperature, pH, Eh, and dissolved O2 were determined on-site. Total alkalinity and F were determined on the day of sample collection. Flame atomic-absorption spectrometry was used to determine concentrations of Li, Na, K, Ca, and Mg. Ultraviolet/visible spectrophotometry was used to determine concentrations of Fe(II), Fe(III), As(III), and As(V). Direct-current plasma-optical-emission spectrometry was used to determine the concentrations of B, Ba, Cd, Cs, Cu, Mn, Ni, Pb, Rb, Sr, and Zn. Two samples collected from Yellowstone Park in June 1974 were used as reference samples for testing the plasma analytical method. Results of these tests demonstrate acceptable precision for all detectable elements. Charge imbalance calculations revealed a small number of samples that may have been subject to measurement errors in pH or alkalinity. These data represent some of the most complete analyses of Yellowstone waters available.

Sequence requirement of the ade6-4095 meiotic recombination hotspot in Schizosaccharomyces pombe.

PubMed

Foulis, Steven J; Fowler, Kyle R; Steiner, Walter W

2018-02-01

Homologous recombination occurs at a greatly elevated frequency in meiosis compared to mitosis and is initiated by programmed double-strand DNA breaks (DSBs). DSBs do not occur at uniform frequency throughout the genome in most organisms, but occur preferentially at a limited number of sites referred to as hotspots. The location of hotspots have been determined at nucleotide-level resolution in both the budding and fission yeasts, and while several patterns have emerged regarding preferred locations for DSB hotspots, it remains unclear why particular sites experience DSBs at much higher frequency than other sites with seemingly similar properties. Short sequence motifs, which are often sites for binding of transcription factors, are known to be responsible for a number of hotspots. In this study we identified the minimum sequence required for activity of one of such motif identified in a screen of random sequences capable of producing recombination hotspots. The experimentally determined sequence, GGTCTRGACC, closely matches the previously inferred sequence. Full hotspot activity requires an effective sequence length of 9.5 bp, whereas moderate activity requires an effective sequence length of approximately 8.2 bp and shows significant association with DSB hotspots. In combination with our previous work, this result is consistent with a large number of different sequence motifs capable of producing recombination hotspots, and supports a model in which hotspots can be rapidly regenerated by mutation as they are lost through recombination.

Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots.

PubMed

Neubauer, Thomas A; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg

2015-09-15

Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins.

Tectonics, climate, and the rise and demise of continental aquatic species richness hotspots

PubMed Central

Neubauer, Thomas A.; Harzhauser, Mathias; Georgopoulou, Elisavet; Kroh, Andreas; Mandic, Oleg

2015-01-01

Continental aquatic species richness hotspots are unevenly distributed across the planet. In present-day Europe, only two centers of biodiversity exist (Lake Ohrid on the Balkans and the Caspian Sea). During the Neogene, a wide variety of hotspots developed in a series of long-lived lakes. The mechanisms underlying the presence of richness hotspots in different geological periods have not been properly examined thus far. Based on Miocene to Recent gastropod distributions, we show that the existence and evolution of such hotspots in inland-water systems are tightly linked to the geodynamic history of the European continent. Both past and present hotspots are related to the formation and persistence of long-lived lake systems in geological basins or to isolation of existing inland basins and embayments from the marine realm. The faunal evolution within hotspots highly depends on warm climates and surface area. During the Quaternary icehouse climate and extensive glaciations, limnic biodiversity sustained a severe decline across the continent and most former hotspots disappeared. The Recent gastropod distribution is mainly a geologically young pattern formed after the Last Glacial Maximum (19 ky) and subsequent formation of postglacial lakes. The major hotspots today are related to long-lived lakes in preglacially formed, permanently subsiding geological basins. PMID:26305934

Effects of perturbations and radial profiles on ignition of inertial confinement fusion hotspots

NASA Astrophysics Data System (ADS)

Taylor, S.; Chittenden, J. P.

2014-06-01

Perturbations of inertial confinement fusion hotspots from spherical symmetry cause an increase in the implosion velocity required for ignition, as investigated analytically by [R. Kishony and D. Shvarts, Phys. Plasmas 8, 4925 (2001)] and in numerical studies by many authors. In this paper, we analyse the mechanisms behind this effect by comparing fully 3D fluid simulations of National Ignition Facility targets to a novel analytic model of the thermal energy balance of the hotspot. The analytic model takes into account the radial variation of the state variables within the hotspot and provides an accurate relationship between the hotspot's 0D parameters (ρc, Tc, R , uR, and q) and its heating and cooling rates. The dominant effect of perturbations appears to be an increase in the inflow velocity at the hotspot's surface due to transverse flow of material between perturbation structures, causing premature thermalisation of kinetic energy before the hotspot is fully compressed. In hotspots with a broad perturbation spectrum, thermalisation of energy is inhibited by nonradial motion introduced by mode-mode interaction, reducing the yield further.

Consequences of fire on aquatic nitrate and phosphate dynamics in Yellowstone National Park

Treesearch

James A. Brass; Vincent G. Ambrosia; Philip J. Riggan; Paul D. Sebesta

1996-01-01

Airborne remotely sensed data were collected and analyzed during and following the 1988 Greater Yellowstone Ecosystem (GYE) fires in order to characterize the fire front movements, burn intensities and various vegetative components of selected watersheds. Remotely sensed data were used to categorize the burn intensities as: severely burned, moderately burned, mixed...

Geophagy by yellowstone grizzly bears

USGS Publications Warehouse

Mattson, D.J.; Green, G.I.; Swalley, R.

1999-01-01

We documented 12 sites in the Yellowstone ecosystem where grizzly bears (Ursus arctos horribilis) had purposefully consumed soil (an activity known as geophagy). We also documented soil in numerous grizzly bear feces. Geophagy primarily occurred at sites barren of vegetation where surficial geology had been modified by geothermal activity. There was no evidence of ungulate use at most sites. Purposeful consumption of soil by bears peaked first from March to May and again from August to October, synchronous with peaks in consumption of ungulate meat and mushrooms. Geophageous soils were distinguished from ungulate mineral licks and soils in general by exceptionally high concentrations of potassium (K) and high concentrations of magnesium (Mg) and sulphur (S). Our results do not support the hypotheses that bears were consuming soil to detoxify secondary compounds in grazed foliage, as postulated for primates, or to supplement dietary sodium, as known for ungulates. Our results suggest that grizzly bears could have been consuming soil as an anti-diarrheal.

Detecting Malaria Hotspots: A Comparison of Rapid Diagnostic Test, Microscopy, and Polymerase Chain Reaction.

PubMed

Mogeni, Polycarp; Williams, Thomas N; Omedo, Irene; Kimani, Domtila; Ngoi, Joyce M; Mwacharo, Jedida; Morter, Richard; Nyundo, Christopher; Wambua, Juliana; Nyangweso, George; Kapulu, Melissa; Fegan, Gregory; Bejon, Philip

2017-11-27

Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

77 FR 38824 - Winter Use Plan, Supplemental Draft Environmental Impact Statement, Yellowstone National Park

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-29

... made publicly available at any time. While you can ask us in your comment to withhold your personal... DEPARTMENT OF THE INTERIOR National Park Service [2310-0070-422] Winter Use Plan, Supplemental Draft Environmental Impact Statement, Yellowstone National Park AGENCY: National Park Service, Interior...

Grizzly bear predation links the loss of native trout to the demography of migratory elk in Yellowstone.

PubMed

Middleton, Arthur D; Morrison, Thomas A; Fortin, Jennifer K; Robbins, Charles T; Proffitt, Kelly M; White, P J; McWhirter, Douglas E; Koel, Todd M; Brimeyer, Douglas G; Fairbanks, W Sue; Kauffman, Matthew J

2013-07-07

The loss of aquatic subsidies such as spawning salmonids is known to threaten a number of terrestrial predators, but the effects on alternative prey species are poorly understood. At the heart of the Greater Yellowstone ecosystem, an invasion of lake trout has driven a dramatic decline of native cutthroat trout that migrate up the shallow tributaries of Yellowstone Lake to spawn each spring. We explore whether this decline has amplified the effect of a generalist consumer, the grizzly bear, on populations of migratory elk that summer inside Yellowstone National Park (YNP). Recent studies of bear diets and elk populations indicate that the decline in cutthroat trout has contributed to increased predation by grizzly bears on the calves of migratory elk. Additionally, a demographic model that incorporates the increase in predation suggests that the magnitude of this diet shift has been sufficient to reduce elk calf recruitment (4-16%) and population growth (2-11%). The disruption of this aquatic-terrestrial linkage could permanently alter native species interactions in YNP. Although many recent ecological changes in YNP have been attributed to the recovery of large carnivores--particularly wolves--our work highlights a growing role of human impacts on the foraging behaviour of grizzly bears.

Grizzly bear predation links the loss of native trout to the demography of migratory elk in Yellowstone

PubMed Central

Middleton, Arthur D.; Morrison, Thomas A.; Fortin, Jennifer K.; Robbins, Charles T.; Proffitt, Kelly M.; White, P. J.; McWhirter, Douglas E.; Koel, Todd M.; Brimeyer, Douglas G.; Fairbanks, W. Sue; Kauffman, Matthew J.

2013-01-01

The loss of aquatic subsidies such as spawning salmonids is known to threaten a number of terrestrial predators, but the effects on alternative prey species are poorly understood. At the heart of the Greater Yellowstone ecosystem, an invasion of lake trout has driven a dramatic decline of native cutthroat trout that migrate up the shallow tributaries of Yellowstone Lake to spawn each spring. We explore whether this decline has amplified the effect of a generalist consumer, the grizzly bear, on populations of migratory elk that summer inside Yellowstone National Park (YNP). Recent studies of bear diets and elk populations indicate that the decline in cutthroat trout has contributed to increased predation by grizzly bears on the calves of migratory elk. Additionally, a demographic model that incorporates the increase in predation suggests that the magnitude of this diet shift has been sufficient to reduce elk calf recruitment (4–16%) and population growth (2–11%). The disruption of this aquatic–terrestrial linkage could permanently alter native species interactions in YNP. Although many recent ecological changes in YNP have been attributed to the recovery of large carnivores—particularly wolves—our work highlights a growing role of human impacts on the foraging behaviour of grizzly bears. PMID:23677350

Grizzly bear predation links the loss of native trout to the demography of migratory elk in Yellowstone

USGS Publications Warehouse

Middleton, Arthur D.; Morrison, Thomas A.; Fortin, Jennifer K.; Robbins, Charles T.; Proffitt, Kelly M.; White, P.J.; McWhirter, Douglas E.; Koel, Todd M.; Brimeyer, Douglas G.; Fairbanks, W. Sue; Kauffman, Matthew J.

2013-01-01

The loss of aquatic subsidies such as spawning salmonids is known to threaten a number of terrestrial predators, but the effects on alternative prey species are poorly understood. At the heart of the Greater Yellowstone ecosystem, an invasion of lake trout has driven a dramatic decline of native cutthroat trout that migrate up the shallow tributaries of Yellowstone Lake to spawn each spring. We explore whether this decline has amplified the effect of a generalist consumer, the grizzly bear, on populations of migratory elk that summer inside Yellowstone National Park (YNP). Recent studies of bear diets and elk populations indicate that the decline in cutthroat trout has contributed to increased predation by grizzly bears on the calves of migratory elk. Additionally, a demographic model that incorporates the increase in predation suggests that the magnitude of this diet shift has been sufficient to reduce elk calf recruitment (4–16%) and population growth (2–11%). The disruption of this aquatic–terrestrial linkage could permanently alter native species interactions in YNP. Although many recent ecological changes in YNP have been attributed to the recovery of large carnivores—particularly wolves—our work highlights a growing role of human impacts on the foraging behaviour of grizzly bears.

Effectively identifying regulatory hotspots while capturing expression heterogeneity in gene expression studies

PubMed Central

2014-01-01

Expression quantitative trait loci (eQTL) mapping is a tool that can systematically identify genetic variation affecting gene expression. eQTL mapping studies have shown that certain genomic locations, referred to as regulatory hotspots, may affect the expression levels of many genes. Recently, studies have shown that various confounding factors may induce spurious regulatory hotspots. Here, we introduce a novel statistical method that effectively eliminates spurious hotspots while retaining genuine hotspots. Applied to simulated and real datasets, we validate that our method achieves greater sensitivity while retaining low false discovery rates compared to previous methods. PMID:24708878

Imaging the Iceland Hotspot Track Beneath Greenland with Seismic Noise Correlations

NASA Astrophysics Data System (ADS)

Mordret, A.

2017-12-01

During the past 65 million years, the Greenland craton drifted over the Iceland hotspot; however, uncertainties in geodynamic modeling and a lack of geophysical evidence prevent an accurate reconstruction of the hotspot track. I image the Greenland lithosphere down to 300 km depth with seismic noise tomography. The hotspot track is observed as a linear high-velocity anomaly in the middle crust associated with magmatic intrusions. In the upper mantle, the remnant thermal signature of the hotspot manifests as low velocity and low viscosity bodies. This new detailed picture of the Greenland lithosphere will drive more accurate geodynamic reconstructions of tectonic plate motions and prediction of Greenland heat flow, which in turn will enable more precise estimations of the Greenland ice-sheet mass balance.

The hot-spot environment of SW Sex in a low state

NASA Astrophysics Data System (ADS)

Groot, Paul J.; Rutten, René G. M.; van Paradijs, Jan

2000-04-01

Based on observations obtained with the 2.5m Isaac Newton Telescope we show that the characteristics of the SW Sex stars can be explained by the dominance of a `hot-spot' like feature in the accretion disk. In SW Sex this `hot-spot' region is located at a distance of 0.5 RL 1 from the white-dwarf and is best visible at phase ϕ=0.95. The location of the hot-spot as deduced from spectral eclipse mapping coincides with the formation site of the main emission lines. We deduce that this hot-spot region is formed by a shock, which we speculate to be the consequence of a high mass-transfer rate and a long spin-period of the non-magnetic white dwarf.

Recombinational hotspot specific to female meiosis in the mouse major histocompatibility complex.

PubMed

Shiroishi, T; Hanzawa, N; Sagai, T; Ishiura, M; Gojobori, T; Steinmetz, M; Moriwaki, K

1990-01-01

The wm7 haplotype of the major histocompatibility complex (MHC), derived from the Japanese wild mouse Mus musculus molossinus, enhances recombination specific to female meiosis in the K/A beta interval of the MHC. We have mapped crossover points of fifteen independent recombinants from genetic crosses of the wm7 and laboratory haplotypes. Most of them were confined to a short segment of approximately 1 kilobase (kb) of DNA between the A beta 3 and A beta 2 genes, indicating the presence of a female-specific recombinational hotspot. Its location overlaps with a sex-independent hotspot previously identified in the Mus musculus castaneus CAS3 haplotype. We have cloned and sequenced DNA fragments surrounding the hotspot from the wm7 haplotype and the corresponding regions from the hotspot-negative B10.A and C57BL/10 strains. There is no significant difference between the sequences of these three strains, or between these and the published sequences of the CAS3 and C57BL/6 strains. However, a comparison of this A beta 3/A beta 2 hotspot with a previously characterized hotspot in the E beta gene revealed that they have a very similar molecular organization. Each hotspot consists of two elements, the consensus sequence of the mouse middle repetitive MT family and the tetrameric repeated sequences, which are separated by 1 kb of DNA.

Super-resolution chemical imaging with dynamic placement of plasmonic hotspots

NASA Astrophysics Data System (ADS)

Olson, Aeli P.; Ertsgaard, Christopher T.; McKoskey, Rachel M.; Rich, Isabel S.; Lindquist, Nathan C.

2015-08-01

We demonstrate dynamic placement of plasmonic "hotspots" for super-resolution chemical imaging via Surface Enhanced Raman Spectroscopy (SERS). A silver nanohole array surface was coated with biological samples and illuminated with a laser. Due to the large plasmonic field enhancements, blinking behavior of the SERS hotspots was observed and processed using a Stochastic Optical Reconstruction Microscopy (STORM) algorithm enabling localization to within 10 nm. However, illumination of the sample with a single static laser beam (i.e., a slightly defocused Gaussian beam) only produced SERS hotspots in fixed locations on the surface, leaving noticeable gaps in any final image. But, by using a spatial light modulator (SLM), the illumination profile of the beam could be altered, shifting any hotspots across the nanohole array surface in sub-wavelength steps. Therefore, by properly structuring an illuminating light field with the SLM, we show the possibility of positioning plasmonic hotspots over a metallic nanohole surface on-the-fly. Using this and our SERS-STORM imaging technique, we show potential for high-resolution chemical imaging without the noticeable gaps that were present with static laser illumination. Interestingly, even illuminating the surface with randomly shifting SLM phase profiles was sufficient to completely fill in a wide field of view for super-resolution SERS imaging of a single strand of 100-nm thick collagen protein fibrils. Images were then compared to those obtained with a scanning electron microscope (SEM). Additionally, we explored alternative methods of phase shifting other than holographic illumination through the SLM to create localization of hotspots necessary for SERS-STORM imaging.

A review of crust and upper mantle structure studies of the Snake River Plain-Yellowstone volcanic system: A major lithospheric anomaly in the western U.S.A.

USGS Publications Warehouse

Iyer, H.M.

1984-01-01

The Snake River Plain-Yellowstone volcanic system is one of the largest, basaltic, volcanic field in the world. Here, there is clear evidence for northeasterly progression of rhyolitic volcanism with its present position in Yellowstone. Many theories have been advanced for the origin of the Snake River Plain-Yellowstone system. Yellowstone and Eastern Snake River Plain have been studied intensively using various geophysical techniques. Some sparse geophysical data are available for the Western Snake River Plain as well. Teleseismic data show the presence of a large anomalous body with low P- and S-wave velocities in the crust and upper mantle under the Yellowstone caldera. A similar body in which compressional wave velocity is lower than in the surrounding rock is present under the Eastern Snake River Plain. No data on upper mantle anomalies are available for the Western Snake River Plain. Detailed seismic refraction data for the Eastern Snake River Plain show strong lateral heterogeneities and suggest thinning of the granitic crust from below by mafic intrusion. Available data for the Western Snake River Plain also show similar thinning of the upper crust and its replacement by mafic material. The seismic refraction results in Yellowstone show no evidence of the low-velocity anomalies in the lower crust suggested by teleseismic P-delay data and interpreted as due to extensive partial melting. However, the seismic refraction models indicate lower-than-normal velocities and strong lateral inhomogeneities in the upper crust. Particularly obvious in the refraction data are two regions of very low seismic velocities near the Mallard Eake and Sour Creek resurgent domes in the Yellowstone caldera. The low-velocity body near the Sour Creek resurgent dome is intepreted as partially molten rock. Together with other geophysical and thermal data, the seismic results indicate that a sub-lithospheric thermal anomaly is responsible for the time-progressive volcanism along the

Continued warming could transform Greater Yellowstone fire regimes by mid-21st century

Treesearch

Anthony L. Westerling; Monica G. Turner; Erica A. H. Smithwick; William H. Romme; Michael G. Ryan

2011-01-01

Climate change is likely to alter wildfire regimes, but the magnitude and timing of potential climate-driven changes in regional fire regimes are not well understood. We considered how the occurrence, size, and spatial location of large fires might respond to climate projections in the Greater Yellowstone ecosystem (GYE) (Wyoming), a large wildland ecosystem dominated...

Background heatflow on hotspot planets - Io and Venus

NASA Technical Reports Server (NTRS)

Stevenson, David J.; Mcnamara, Sean C.

1988-01-01

It is suggested that there is no simple relationship between lithospheric thickness and heatflow on planets where volcanism dominates the heatflow. This applies locally and globally, even away from regions of volcanic activity. This indicates that there is no basis for the assumption that the Io heatflow is as low as (or lower than) the hotspot component alone would suggest. A model is presented to describe the heatflow on hotspot planets. The model is applied to Io and Venus.

Geologic evidence of hotspot activity of Venus - Predictions for Magellan

NASA Technical Reports Server (NTRS)

Stofan, Ellen R.; Saunders, R. Stephen

1990-01-01

A number of distinctive types of geologic features have been identified on Venus that are interpreted to be related to thermal plumes including domal rises, coronae, and major composite shield volcanoes. The basic characteristics of these features as well as their distribution are documented. The three types of features have related morphologies and are interpreted to represent a continuum of features formed by mantle plumes at scales from 100s to over 1000 km. The Artemis structure, located in Aphrodite Terra, is proposed to be a large corona. If crustal spreading processes are operating on Venus, hotspot features should form chains on the surface as seen in terrestrial ocean basins. On the basis of current data on hotspot-related feature distribution on Venus, no clear evidence exists for hotspot chains. The complete distribution of hotspot features in Magellan data will be used to understand better the relationship between interior processes and surface features, as well as to provide a test for the crustal spreading hypothesis.

The Impact of Field Experiences in Yellowstone National Park on Practice in Secondary Classrooms

ERIC Educational Resources Information Center

McGrew, Christopher N.

2012-01-01

The current study focused on how six participants of a 2009 professional development activity at Yellowstone National Park described their experience and classroom instructional impact. The author focused on words and phrases illustrating perspective gathering, reflection and public performance to determine the impact of both the experience at…

River solute fluxes reflecting active hydrothermal chemical weathering of the Yellowstone Plateau Volcanic Field, USA

USGS Publications Warehouse

Hurwitz, S.; Evans, William C.; Lowenstern, J. B.

2010-01-01

In the past few decades numerous studies have quantified the load of dissolved solids in large rivers to determine chemical weathering rates in orogenic belts and volcanic areas, mainly motivated by the notion that over timescales greater than ~100kyr, silicate hydrolysis may be the dominant sink for atmospheric CO2, thus creating a feedback between climate and weathering. Here, we report the results of a detailed study during water year 2007 (October 1, 2006 to September 30, 2007) in the major rivers of the Yellowstone Plateau Volcanic Field (YPVF) which hosts Earth's largest "restless" caldera and over 10,000 thermal features. The chemical compositions of rivers that drain thermal areas in the YPVF differ significantly from the compositions of rivers that drain non-thermal areas. There are large seasonal variations in river chemistry and solute flux, which increases with increasing water discharge. The river chemistry and discharge data collected periodically over an entire year allow us to constrain the annual solute fluxes and to distinguish between low-temperature weathering and hydrothermal flux components. The TDS flux from Yellowstone Caldera in water year 2007 was 93t/km2/year. Extensive magma degassing and hydrothermal interaction with rocks accounts for at least 82% of this TDS flux, 83% of the cation flux and 72% of the HCO3- flux. The low-temperature chemical weathering rate (17t/km2/year), calculated on the assumption that all the Cl- is of thermal origin, could include a component from low-temperature hydrolysis reactions induced by CO2 ascending from depth rather than by atmospheric CO2. Although this uncertainty remains, the calculated low-temperature weathering rate of the young rhyolitic rocks in the Yellowstone Caldera is comparable to the world average of large watersheds that drain also more soluble carbonates and evaporates but is slightly lower than calculated rates in other, less-silicic volcanic regions. Long-term average fluxes at

Space Radar Image of Yellowstone Park, Wyoming

NASA Technical Reports Server (NTRS)

1994-01-01

These two radar images show the majestic Yellowstone National Park, Wyoming, the oldest national park in the United States and home to the world's most spectacular geysers and hot springs. The region supports large populations of grizzly bears, elk and bison. In 1988, the park was burned by one of the most widespread fires to occur in the northern Rocky Mountains in the last 50 years. Surveys indicated that 793,880 acres of land burned. Of that, 41 percent was burned forest, with tree canopies totally consumed by the fire; 35 percent was a combination of unburned, scorched and blackened trees; 13 percent was surface burn under an unburned canopy; 6 percent was non-forest burn; and 5 percent was undifferentiated burn. Six years later, the burned areas are still clearly visible in these false-color radar images obtained by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar on board the space shuttle Endeavour. The image at the left was obtained using the L-band radar channel, horizontally received and vertically transmitted, on the shuttle's 39th orbit on October 2, 1994. The area shown is 45 kilometers by 71 kilometers (28 miles by 44 miles) in size and centered at 44.6 degrees north latitude, 110.7 degrees west longitude. North is toward the top of the image (to the right). Most trees in this area are lodge pole pines at different stages of fire succession. Yellowstone Lake appears as a large dark feature at the bottom of the scene. At right is a map of the forest crown, showing its biomass, or amount of vegetation, which includes foliage and branches. The map was created by inverting SIR-C data and using in situ estimates of crown biomass gathered by the Yellowstone National Biological Survey. The map is displayed on a color scale from blue (rivers and lakes with no biomass) to brown (non-forest areas with crown biomass of less than 4 tons per hectare) to light brown (areas of canopy burn with biomass of between 4 and 12 tons per hectare). Yellow

Use of ASTER and MODIS thermal infrared data to quantify heat flow and hydrothermal change at Yellowstone National Park

USGS Publications Warehouse

Vaughan, R. Greg; Keszthelyi, Laszlo P.; Lowenstern, Jacob B.; Jaworowski, Cheryl; Heasler, Henry

2012-01-01

The overarching aim of this study was to use satellite thermal infrared (TIR) remote sensing to monitor geothermal activity within the Yellowstone geothermal area to meet the missions of both the U.S. Geological Survey and the Yellowstone National Park Geology Program. Specific goals were to: 1) address the challenges of monitoring the surface thermal characteristics of the > 10,000 spatially and temporally dynamic thermal features in the Park (including hot springs, pools, geysers, fumaroles, and mud pots) that are spread out over ~ 5000 km2, by using satellite TIR remote sensing tools (e.g., ASTER and MODIS), 2) to estimate the radiant geothermal heat flux (GHF) for Yellowstone's thermal areas, and 3) to identify normal, background thermal changes so that significant, abnormal changes can be recognized, should they ever occur (e.g., changes related to tectonic, hydrothermal, impending volcanic processes, or human activities, such as nearby geothermal development). ASTER TIR data (90-m pixels) were used to estimate the radiant GHF from all of Yellowstone's thermal features and update maps of thermal areas. MODIS TIR data (1-km pixels) were used to record background thermal radiance variations from March 2000 through December 2010 and establish thermal change detection limits. A lower limit for the radiant GHF estimated from ASTER TIR temperature data was established at ~ 2.0 GW, which is ~ 30–45% of the heat flux estimated through geochemical thermometry. Also, about 5 km2 of thermal areas was added to the geodatabase of mapped thermal areas. A decade-long time-series of MODIS TIR radiance data was dominated by seasonal cycles. A background subtraction technique was used in an attempt to isolate variations due to geothermal changes. Several statistically significant perturbations were noted in the time-series from Norris Geyser Basin, however many of these did not correspond to documented thermal disturbances. This study provides concrete examples of the

Characterizing local biological hotspots in the Gulf of Maine using remote sensing data

NASA Astrophysics Data System (ADS)

Ribera, Marta M.

Researchers increasingly advocate the use of ecosystem-based management (EBM) for managing complex marine ecosystems. This approach requires managers to focus on processes and cross-scale interactions, rather than individual components. However, they often lack appropriate tools and data sources to pursue this change in management approach. One method that has been proposed to understand the ecological complexity inherent in marine ecosystems is the study of biological hotspots. Biological hotspots are locations where organisms from different trophic levels aggregate to feed on abundant supplies, and they are considered a first step toward understanding the processes driving spatial and temporal heterogeneity in marine systems. Biological hotspots are supported by phytoplankton aggregations, which are characterized by high spatial and temporal variability. As a result, methods developed to locate biological hotspots in relatively stable terrestrial systems are not well suited for more dynamic marine ecosystems. The main objective of this thesis is thus to identify and characterize local-scale biological hotspots in the western side of the Gulf of Maine. The first chapter describes a new methodological framework with the steps needed to locate these types of hotspots in marine ecosystems using remote sensing datasets. Then, in the second chapter these hotspots are characterized using a novel metric that uses time series information and spatial statistics to account for both the temporal variability and spatial structure of these marine aggregations. This metric redefines biological hotspots as areas with a high probability of exhibiting positive anomalies of productivity compared to the expected regional seasonal pattern. Finally, the third chapter compares the resulting biological hotspots to fishery-dependent abundance indices of surface and benthic predators to determine the effect of the location and magnitude of phytoplankton aggregations on the rest of the

Wafer hotspot prevention using etch aware OPC correction

NASA Astrophysics Data System (ADS)

Hamouda, Ayman; Power, Dave; Salama, Mohamed; Chen, Ao

2016-03-01

As technology development advances into deep-sub-wavelength nodes, multiple patterning is becoming more essential to achieve the technology shrink requirements. Recently, Optical Proximity Correction (OPC) technology has proposed simultaneous correction of multiple mask-patterns to enable multiple patterning awareness during OPC correction. This is essential to prevent inter-layer hot-spots during the final pattern transfer. In state-of-art literature, multi-layer awareness is achieved using simultaneous resist-contour simulations to predict and correct for hot-spots during mask generation. However, this approach assumes a uniform etch shrink response for all patterns independent of their proximity, which isn't sufficient for the full prevention of inter-exposure hot-spot, for example different color space violations post etch or via coverage/enclosure post etch. In this paper, we explain the need to include the etch component during multiple patterning OPC. We also introduce a novel approach for Etch-aware simultaneous Multiple-patterning OPC, where we calibrate and verify a lumped model that includes the combined resist and etch responses. Adding this extra simulation condition during OPC is suitable for full chip processing from a computation intensity point of view. Also, using this model during OPC to predict and correct inter-exposures hot-spots is similar to previously proposed multiple-patterning OPC, yet our proposed approach more accurately corrects post-etch defects too.

Geologic studies of Yellowstone National Park imagery using an electronic image enhancement system

NASA Technical Reports Server (NTRS)

Smedes, H. W.

1970-01-01

The image enhancement system is described, as well as the kinds of enhancement attained. Results were obtained from various kinds of remote sensing imagery (mainly black and white multiband, color, color infrared, thermal infrared, and side-looking K-band radar) of parts of Yellowstone National Park. Possible additional fields of application of these techniques are considered.

The climate adaptation programs and activities of the Yellowstone to Yukon Conservation Initiative

Treesearch

Wendy L. Francis

2011-01-01

The Yellowstone to Yukon Conservation Initiative (Y2Y) is an innovative transboundary effort to protect biodiversity and facilitate climate adaptation by linking large protected core areas through compatible land uses on matrix lands. The Y2Y organization acts as the keeper of the Y2Y vision and implements two interconnected programs - Science and Action, and Vision...

Sexual predators, energy development, and conservation in greater Yellowstone.

PubMed

Berger, Joel; Beckmann, Jon P

2010-06-01

In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies-recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)-differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in-migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.

Distribution of enzyme activity hotspots induced by earthworms in top- and subsoil

NASA Astrophysics Data System (ADS)

Hoang, D. T. T.

2016-12-01

Earthworms (Lumbricus terrestris L.) not only affect soil physics, but they also boost microbial activities and consequently create important hotspots of microbial mediated carbon and nutrient turnover through their burrowing activity. However, it is still unknown to which extend earthworms change the enzyme distribution and activity inside their burrows in top- and subsoil horizons. We hypothesized that earthworm burrows, which are enriched in available substrates, have higher percentage of enzyme activity hotspots than soil without earthworms, and that enzyme activities decreased with increasing depth because of the increasing recalcitrance of organic matter in subsoil. We visualized enzyme distribution inside and outside of worm burrows (biopores) by in situ soil zymography and measured enzyme kinetics of 6 enzymes - β-glucosidase (GLU), cellobiohydrolase (CBH), xylanase (XYL), chitinase (NAG), leucine aminopeptidase (LAP) and acid phosphatase (APT) - in pore and bulk soil material up to 105 cm. Zymography showed a heterogeneous distribution of hotspots in worm burrows. The hotspot areas was 2.4 to 14 times larger in the burrows than in soil without earthworms. However, the dispersion index of hotspot distribution showed more aggregated hotspots in soil without earthworms than in soil with earthworms and burrow wall. Enzyme activities decreased with depth, by a factor of 2 to 8 due to fresh C input from the soil surface. Compared to bulk soil, enzyme activities in topsoil biopores were up to 11 times higher for all enzymes, but in the subsoil activities of XYL, NAG and APT were lower in earthworm biopores than bulk soil. In conclusion, hotspots were twice as concentrated close to earthworm burrows as in surrounding soil. Earthworms exerted stronger effects on enzyme activities in biopores in the topsoil than in subsoil. Keywords: Earthworms, hotspots, enzyme activities, enzyme distribution, subsoil

The Yellowstone ‘hot spot’ track results from migrating Basin Range extension

USGS Publications Warehouse

Foulger, Gillian R.; Christiansen, Robert L.; Anderson, Don L.; Foulger, Gillian R.; Lustrino, Michele; King, Scott D.

2015-01-01

Whether the volcanism of the Columbia River Plateau, eastern Snake River Plain, and Yellowstone (western U.S.) is related to a mantle plume or to plate tectonic processes is a long-standing controversy. There are many geological mismatches with the basic plume model as well as logical flaws, such as citing data postulated to require a deep-mantle origin in support of an “upper-mantle plume” model. USArray has recently yielded abundant new seismological results, but despite this, seismic analyses have still not resolved the disparity of opinion. This suggests that seismology may be unable to resolve the plume question for Yellowstone, and perhaps elsewhere. USArray data have inspired many new models that relate western U.S. volcanism to shallow mantle convection associated with subduction zone processes. Many of these models assume that the principal requirement for surface volcanism is melt in the mantle and that the lithosphere is essentially passive. In this paper we propose a pure plate model in which melt is commonplace in the mantle, and its inherent buoyancy is not what causes surface eruptions. Instead, it is extension of the lithosphere that permits melt to escape to the surface and eruptions to occur—the mere presence of underlying melt is not a sufficient condition. The time-progressive chain of rhyolitic calderas in the eastern Snake River Plain–Yellowstone zone that has formed since basin-range extension began at ca. 17 Ma results from laterally migrating lithospheric extension and thinning that has permitted basaltic magma to rise from the upper mantle and melt the lower crust. We propose that this migration formed part of the systematic eastward migration of the axis of most intense basin-range extension. The bimodal rhyolite-basalt volcanism followed migration of the locus of most rapid extension, not vice versa. This model does not depend on seismology to test it but instead on surface geological observations.

Volcano and Earthquake Monitoring Plan for the Yellowstone Volcano Observatory, 2006-2015

USGS Publications Warehouse

,

2006-01-01

To provide Yellowstone National Park (YNP) and its surrounding communities with a modern, comprehensive system for volcano and earthquake monitoring, the Yellowstone Volcano Observatory (YVO) has developed a monitoring plan for the period 2006-2015. Such a plan is needed so that YVO can provide timely information during seismic, volcanic, and hydrothermal crises and can anticipate hazardous events before they occur. The monitoring network will also provide high-quality data for scientific study and interpretation of one of the largest active volcanic systems in the world. Among the needs of the observatory are to upgrade its seismograph network to modern standards and to add five new seismograph stations in areas of the park that currently lack adequate station density. In cooperation with the National Science Foundation (NSF) and its Plate Boundary Observatory Program (PBO), YVO seeks to install five borehole strainmeters and two tiltmeters to measure crustal movements. The boreholes would be located in developed areas close to existing infrastructure and away from sensitive geothermal features. In conjunction with the park's geothermal monitoring program, installation of new stream gages, and gas-measuring instruments will allow YVO to compare geophysical phenomena, such as earthquakes and ground motions, to hydrothermal events, such as anomalous water and gas discharge. In addition, YVO seeks to characterize the behavior of geyser basins, both to detect any precursors to hydrothermal explosions and to monitor earthquakes related to fluid movements that are difficult to detect with the current monitoring system. Finally, a monitoring network consists not solely of instruments, but requires also a secure system for real-time transmission of data. The current telemetry system is vulnerable to failures that could jeopardize data transmission out of Yellowstone. Future advances in monitoring technologies must be accompanied by improvements in the infrastructure for

Contrasting past and current numbers of bears visiting Yellowstone cutthroat trout streams

USGS Publications Warehouse

Haroldson, Mark A.; Schwartz, Charles C.; Teisberg, Justin E.; Gunther, Kerry A.; Fortin, Jennifer K.; Robbins, Charles T.

2014-01-01

Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone’s grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake trout (Salvelinus namaycush), and in response to effects of drought and whirling disease (Myxobolus cerebralis). The trout population, duration of spawning runs, and indices of bear use of spawning streams had declined in some regions of the lake by 1997–2000. We initiated a 3-year study in 2007 to assess whether numbers of spawning fish, black bears, and grizzly bears within and alongside stream corridors had changed since 1997– 2000. We estimated numbers of grizzly bears and black bears by first compiling encounter histories of individual bears visiting 48 hair-snag sites along 35 historically fished streams.We analyzed DNA encounter histories with Pradel-recruitment and Jolly-Seber (POPAN) capture-mark-recapture models. When compared to 1997–2000, the current number of spawning cutthroat trout per stream and the number of streams with cutthroat trout has decreased. We estimated that 48 (95% CI¼42–56) male and 23 (95% CI¼21–27) female grizzly bears visited the historically fished tributary streams during our study. In any 1- year, 46 to 59 independent grizzly bears (8–10% of estimated Greater Yellowstone Ecosystem population) visited these streams. When compared with estimates from the 1997 to 2000 study and adjusted for equal effort, the number of grizzly bears using the stream corridors decreased by 63%. Additionally, the number of black bears decreased between 64% and 84%. We also document an increased proportion of bears of both species visiting front-country (i.e., near human development) streams. With the recovery of cutthroat trout, we suggest bears

Kimama Well - Borehole Geophysics Database

DOE Data Explorer

Shervais, John

2011-07-04

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Kimama drill site was set up to acquire a continuous record of basaltic volcanism along the central volcanic axis and to test the extent of geothermal resources beneath the Snake River aquifer. Data submitted by project collaborator Doug Schmitt, University of Alberta

Kimama Well - Photos

DOE Data Explorer

Shervais, John

2011-01-16

The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Kimama drill site was set up to acquire a continuous record of basaltic volcanism along the central volcanic axis and to test the extent of geothermal resources beneath the Snake River aquifer. Data submitted by project collaborator Doug Schmitt, University of Alberta

Tracing global supply chains to air pollution hotspots

NASA Astrophysics Data System (ADS)

Moran, Daniel; Kanemoto, Keiichiro

2016-09-01

While high-income countries have made significant strides since the 1970s in improving air quality, air pollution continues to rise in many developing countries and the world as a whole. A significant share of the pollution burden in developing countries can be attributed to production for export to consumers in high-income nations. However, it remains a challenge to quantify individual actors’ share of responsibility for pollution, and to involve parties other than primary emitters in cleanup efforts. Here we present a new spatially explicit modeling approach to link SO2, NO x , and PM10 severe emissions hotspots to final consumers via global supply chains. These maps show developed countries reducing their emissions domestically but driving new pollution hotspots in developing countries. This is also the first time a spatially explicit footprint inventory has been established. Linking consumers and supply chains to emissions hotspots creates opportunities for other parties to participate alongside primary emitters and local regulators in pollution abatement efforts.

Forecasts of 21st Century Snowpack and Implications for Snowmobile and Snowcoach Use in Yellowstone National Park

PubMed Central

Tercek, Michael; Rodman, Ann

2016-01-01

Climate models project a general decline in western US snowpack throughout the 21st century, but long-term, spatially fine-grained, management-relevant projections of snowpack are not available for Yellowstone National Park. We focus on the implications that future snow declines may have for oversnow vehicle (snowmobile and snowcoach) use because oversnow tourism is critical to the local economy and has been a contentious issue in the park for more than 30 years. Using temperature-indexed snow melt and accumulation equations with temperature and precipitation data from downscaled global climate models, we forecast the number of days that will be suitable for oversnow travel on each Yellowstone road segment during the mid- and late-21st century. The west entrance road was forecast to be the least suitable for oversnow use in the future while the south entrance road was forecast to remain at near historical levels of driveability. The greatest snow losses were forecast for the west entrance road where as little as 29% of the December–March oversnow season was forecast to be driveable by late century. The climatic conditions that allow oversnow vehicle use in Yellowstone are forecast by our methods to deteriorate significantly in the future. At some point it may be prudent to consider plowing the roads that experience the greatest snow losses. PMID:27467778

Modulation of an ultraviolet mutational hotspot in a shuttle vector Xeroderma cells.

PubMed Central

Seetharam, S; Seidman, M M

1991-01-01

Ultraviolet mutagenesis of the shuttle vector plasmid pZ189 in Xeroderma Pigmentosum cells yields a mutational pattern marked by hotspots at photoproduct sites on both strands of the supF marker gene. In order to test the influence of strand orientation on the appearance of hotspots the mutagenesis study was repeated on a vector with the supF gene in the inverted orientation. We recovered a pattern the same as that in the earlier work and conclude that the nature of the DNA polymerase involved in the replication of specific strands is not a primary determinant of hotspot occurrence in this system. One of the hotspots lies in an 8 base palindrome while the corresponding site on the other strand was not a hotspot. These results were obtained with calcium phosphate transfection of the UV treated vector. When DEAE dextran was used as a transfection agent both sites in the palindrome were hotspots. In a mixing experiment the calcium phosphate pattern was recovered. Our data suggest that the sequence determinants of mutational probability at these two sites lie outside the 8 bases of the palindrome and that mutagenesis at one, but not the other, site is sensitive to perturbation of cellular calcium levels. PMID:2027767

New geothermal heat flux map of Greenland and the Iceland hotspot track

NASA Astrophysics Data System (ADS)

Martos, Y. M.; Jordan, T. A.; Catalan, M.; Jordan, T. M.; Bamber, J. L.; Vaughan, D. G.

2017-12-01

Greenland is the second largest reservoir of water on Earth and about 80% of its surface is covered by ice. It is mainly composed of Archean blocks that collided during the Early Proterozoic. Indirect methods have been used to study its subglacial thermal conditions, geology and lithospheric structure. Numerous regions of basal melting are identified in the central and north Greenland but their relationship with geothermal heat flux is not yet clear. Crustal thickness derived by seismology and gravity data are consistent, showing no significant lateral variations, and providing average values of about 40 and 36 km respectively. Even though Greenland is considered a craton its crust has been affected by the presume passage of the Iceland hotspot since at least 100 Ma. Here we present the newest and highest resolution Curie Depth and geothermal heat flux maps for Greenland as well as their associated uncertainties. For estimating the Curie Depths we applied spectral methods to aeromagnetic data from the World Digital Magnetic Anomaly Map WDMAM2.0. Calculated Curie Depths vary from 25 to 50 km with shallower values located to the east. A thermal model is built based on the 1D heat conduction equation and considering steady state conditions. The thermal parameters are then optimized using local values derived from direct measurements, temperature profiles and more indirect methods such as radar imaging. The heat flux distribution shows higher spatial variability and a very different pattern than previously proposed and with values of 50-80 mW/m2. We identify a NW-SE high heat flux feature crossing Greenland which we correlate with the Iceland hotspot track. Additionally, to evaluate the lithospheric structure we calculate the Bouguer anomaly from GOCO5s satellite free air data and construct several gravity models across the proposed hotspot track. We show that a dense lower crust body in the same location the high heat flux trend is permissible from a gravimetric

The Geologic Story of Yellowstone National Park

USGS Publications Warehouse

Keefer, William Richard

1971-01-01

In the aftermath of the Civil War, the United States expanded the exploration of her western frontiers to gain a measure of the vast lands and natural resources in the region now occupied by our Rocky Mountain States. As part of this effort, the Geological and Geographical Survey of the Territories was organized within the Department of the Interior, and staffed by a group of hardy, pioneering scientists under the leadership of geologist F. V. Hayden. During the summer of 1871, these men, accompanied by photographer William H. Jackson and artist Thomas Moran, made a reconnaissance geological study of the legendary and mysterious 'Yellowstone Wonderland' in remote northwestern Wyoming Territory. The scientific reports and illustrations prepared by Hayden and his colleagues, supplementing the startling accounts that had been published by members of the famous Washburn-Doane Expedition a year earlier, erased all doubts that this unique land was eminently worthy of being set aside 'for the benefit and enjoyment of the people.' By Act of Congress on March 1, 1872, our first National Park was established. During the past century, 50 million people have toured Yellowstone National Park, marveling at its never-ending display of natural wonders. No doubt many have paused to wonder about the origin of these unusual and complex geological features - a question, needless to say, that has intrigued and challenged scientists from the very first days of the Hayden Survey. During the past decade a group of U. S. Geological Survey scientists, in cooperation with the National Park Service and aided by the interest of the National Aeronautics and Space Administration in remote sensing of the geologic phenomena, has been probing the depths and farthest corners of the Park seeking more of the answers. Some of the results of this work, and those of earlier studies, are described in this book to provide a better understanding and enjoyment of this great National Park.

The history, hotspots, and trends of electrocardiogram.

PubMed

Yang, Xiang-Lin; Liu, Guo-Zhen; Tong, Yun-Hai; Yan, Hong; Xu, Zhi; Chen, Qi; Liu, Xiang; Zhang, Hong-Hao; Wang, Hong-Bo; Tan, Shao-Hua

2015-07-01

The electrocardiogram (ECG) has broad applications in clinical diagnosis and prognosis of cardiovascular disease. Many researchers have contributed to its progressive development. To commemorate those pioneers, and to better study and promote the use of ECG, we reviewed and present here a systematic introduction about the history, hotspots, and trends of ECG. In the historical part, information including the invention, improvement, and extensive applications of ECG, such as in long QT syndrome (LQTS), angina, and myocardial infarction (MI), are chronologically presented. New technologies and applications from the 1990s are also introduced. In the second part, we use the bibliometric analysis method to analyze the hotspots in the field of ECG-related research. By using total citations and year-specific total citations as our main criteria, four key hotspots in ECG-related research were identified from 11 articles, including atrial fibrillation, LQTS, angina and MI, and heart rate variability. Recent studies in those four areas are also reported. In the final part, we discuss the future trends concerning ECG-related research. The authors believe that improvement of the ECG instrumentation, big data mining for ECG, and the accuracy of diagnosis and application will be areas of continuous concern.

Ectomycorrhizal Specificity Patterns in a Mixed Pinus contorta and Picea engelmannii Forest in Yellowstone National Park

PubMed Central

Cullings, Kenneth W.; Vogler, Detlev R.; Parker, Virgil T.; Finley, Sara Katherine

2000-01-01

We used molecular genetic methods to test two hypotheses, (i) that host plant specificity among ectomycorrhizal fungi would be common in a closed-canopy, mixed Pinus contorta-Picea engelmannii forest in Yellowstone National Park and (ii) that specificity would be more common in the early successional tree species, P. contorta, than in the invader, P. engelmannii. We identified 28 ectomycorrhizal fungal species collected from 27 soil cores. The proportion of P. engelmannii to P. contorta ectomycorrhizae was nearly equal (52 and 48%, respectively). Of the 28 fungal species, 18 composed greater than 95% of the fungal community. No species was associated exclusively with P. contorta, but four species, each found in only one core, and one species found in two cores were associated exclusively with P. engelmannii. These fungi composed less than 5% of the total ectomycorrhizae. Thus, neither hypothesis was supported, and hypothesized benefits of ectomycorrhizal specificity to both trees and fungi probably do not exist in this system. PMID:11055953

Ectomycorrhizal specificity patterns in a mixed Pinus contorta and Picea engelmannii forest in Yellowstone National Park

NASA Technical Reports Server (NTRS)

Cullings, K. W.; Vogler, D. R.; Parker, V. T.; Finley, S. K.

2000-01-01

We used molecular genetic methods to test two hypotheses, (i) that host plant specificity among ectomycorrhizal fungi would be common in a closed-canopy, mixed Pinus contorta-Picea engelmannii forest in Yellowstone National Park and (ii) that specificity would be more common in the early successional tree species, P. contorta, than in the invader, P. engelmannii. We identified 28 ectomycorrhizal fungal species collected from 27 soil cores. The proportion of P. engelmannii to P. contorta ectomycorrhizae was nearly equal (52 and 48%, respectively). Of the 28 fungal species, 18 composed greater than 95% of the fungal community. No species was associated exclusively with P. contorta, but four species, each found in only one core, and one species found in two cores were associated exclusively with P. engelmannii. These fungi composed less than 5% of the total ectomycorrhizae. Thus, neither hypothesis was supported, and hypothesized benefits of ectomycorrhizal specificity to both trees and fungi probably do not exist in this system.

Months between rejuvenation and volcanic eruption at Yellowstone caldera, Wyoming

USGS Publications Warehouse

Till, Christy B.; Vazquez, Jorge A.; Boyce, Jeremy W

2015-01-01

Rejuvenation of previously intruded silicic magma is an important process leading to effusive rhyolite, which is the most common product of volcanism at calderas with protracted histories of eruption and unrest such as Yellowstone, Long Valley, and Valles, USA. Although orders of magnitude smaller in volume than rare caldera-forming super-eruptions, these relatively frequent effusions of rhyolite are comparable to the largest eruptions of the 20th century and pose a considerable volcanic hazard. However, the physical pathway from rejuvenation to eruption of silicic magma is unclear particularly because the time between reheating of a subvolcanic intrusion and eruption is poorly quantified. This study uses geospeedometry of trace element profiles with nanometer resolution in sanidine crystals to reveal that Yellowstone’s most recent volcanic cycle began when remobilization of a near- or sub-solidus silicic magma occurred less than 10 months prior to eruption, following a 220,000 year period of volcanic repose. Our results reveal a geologically rapid timescale for rejuvenation and effusion of ~3 km3 of high-silica rhyolite lava even after protracted cooling of the subvolcanic system, which is consistent with recent physical modeling that predict a timescale of several years or less. Future renewal of rhyolitic volcanism at Yellowstone is likely to require an energetic intrusion of mafic or silicic magma into the shallow subvolcanic reservoir and could rapidly generate an eruptible rhyolite on timescales similar to those documented here.

What is “natural”? : Yellowstone elk population - A case study

USGS Publications Warehouse

Keigley, R.B.; Wagner, Frederic H.

2000-01-01

Ecology analyzes the structure and function of ecosystems at all points along the continuum of human disturbance, from so-called pristine forests to urban backyards. Undisturbed systems provide reference points at one end of the spectrum, and nature reserves and parks are highly valued because they can provide unique examples of such ecosystems. Unfortunately the concept of “natural” or pristine is not that easy to define. Indeed, although ecologists have considered pre-Columbian, western-hemisphere ecosystems to have been largely unaltered by human action, and have termed their state “natural” or “pristine,” evidence from archaeology challenges this view. U.S. and Canadian national parks are charged with preserving the “natural,” and thus need to be able to understand and manage for the “natural.” A pivotal “natural” question in Yellowstone National Park management is the size of the northern-range, wintering elk population at Park establishment in 1872, argued both to have been small and large. Integrating and quantifying several sources of evidence provides a consistent picture of a low population (ca. 5,000–6,000), largely migrating out of the northern range in winter, with little vegetation impact. If we accept this conclusion about what is natural for the Yellowstone ecosystem, then it dramatically alters how we view management alternatives for the Park, which currently supports a northern wintering herd of up to ˜ 25,000 elk.

Attributes of Yellowstone cutthroat trout redds in a tributary of the Snake River, Idaho

Treesearch

Russell F. Thurow; John G. King

1994-01-01

We characterized spawning sites of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri, described the microhabitat of completed redds, and tested the influence of habitat conditions on the morphology of completed redds in Pine Creek, Idaho. Cutthroat trout spawned in June as flows subsided after peak stream discharge. During spawning, minimum and maximum water...

Organization and roles of nucleosomes at mouse meiotic recombination hotspots

PubMed Central

Getun, Irina V.; Wu, Zhen K.; Bois, Philippe R.J.

2012-01-01

Meiotic double strand breaks (DSBs) occur at discrete regions in the genome coined hotspots. Precisely what directs site selection of these DSBs is hotly debated and in particular it is unclear which chromatin features, and regulatory factors are necessary for a genomic region to initiate and resolve DSBs as a crossover (CO) event. In human and mouse, one layer of hotspot selection control is a recognition sequence element present at these sites that is bound by the Prdm9 zinc-finger protein. Furthermore, an overall open chromatin structure is thought to be required to allow access of the recombination machinery, and this is often dictated by the packaging of DNA around nucleosomes. We recently defined the nucleosome occupancy maps of four mouse recombination hotspots throughout meiosis. These analyses revealed no obvious dynamic changes in nucleosome occupancy, suggesting an intrinsic nature of recombinogenic sites, yet they also revealed that nucleosomes define zones of exclusion for CO resolution. Here, we discuss new evidence implicating nucleosome occupancy in recombinogenic repair and its potential roles in controlling chromatin structure at mouse meiotic hotspots. PMID:22572955

Reserve networks based on richness hotspots and representation vary with scale.

PubMed

Shriner, Susan A; Wilson, Kenneth R; Flather, Curtis H

2006-10-01

While the importance of spatial scale in ecology is well established, few studies have investigated the impact of data grain on conservation planning outcomes. In this study, we compared species richness hotspot and representation networks developed at five grain sizes. We used species distribution maps for mammals and birds developed by the Arizona and New Mexico Gap Analysis Programs (GAP) to produce 1-km2, 100-kmn2, 625-km2, 2500-km2, and 10,000-km2 grid cell resolution distribution maps. We used these distribution maps to generate species richness and hotspot (95th quantile) maps for each taxon in each state. Species composition information at each grain size was used to develop two types of representation networks using the reserve selection software MARXAN. Reserve selection analyses were restricted to Arizona birds due to considerable computation requirements. We used MARXAN to create best reserve networks based on the minimum area required to represent each species at least once and equal area networks based on irreplaceability values. We also measured the median area of each species' distribution included in hotspot (mammals and birds of Arizona and New Mexico) and irreplaceability (Arizona birds) networks across all species. Mean area overlap between richness hotspot reserves identified at the five grain sizes was 29% (grand mean for four within-taxon/state comparisons), mean overlap for irreplaceability reserve networks was 32%, and mean overlap for best reserve networks was 53%. Hotspots for mammals and birds showed low overlap with a mean of 30%. Comparison of hotspots and irreplaceability networks showed very low overlap with a mean of 13%. For hotspots, median species distribution area protected within reserves declined monotonically from a high of 11% for 1-km2 networks down to 6% for 10,000-km2 networks. Irreplaceability networks showed a similar, but more variable, pattern of decline. This work clearly shows that map resolution has a profound

Hot-spot mix in ignition-scale inertial confinement fusion targets.

PubMed

Regan, S P; Epstein, R; Hammel, B A; Suter, L J; Scott, H A; Barrios, M A; Bradley, D K; Callahan, D A; Cerjan, C; Collins, G W; Dixit, S N; Döppner, T; Edwards, M J; Farley, D R; Fournier, K B; Glenn, S; Glenzer, S H; Golovkin, I E; Haan, S W; Hamza, A; Hicks, D G; Izumi, N; Jones, O S; Kilkenny, J D; Kline, J L; Kyrala, G A; Landen, O L; Ma, T; MacFarlane, J J; MacKinnon, A J; Mancini, R C; McCrory, R L; Meezan, N B; Meyerhofer, D D; Nikroo, A; Park, H-S; Ralph, J; Remington, B A; Sangster, T C; Smalyuk, V A; Springer, P T; Town, R P J

2013-07-26

Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. Low neutron yields and hot-spot mix mass between 34(-13,+50)  ng and 4000(-2970,+17 160)  ng are observed.

Hot-spot mix in ignition-scale inertial confinement fusion targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Regan, S. P.; Epstein, R.; Hammel, B. A.

Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. As a result, low neutron yields and hot-spot mix mass between 34(–13,+50) ng and 4000(–2970,+17 160) ng are observed.

Hot-spot mix in ignition-scale inertial confinement fusion targets

DOE PAGES

Regan, S. P.; Epstein, R.; Hammel, B. A.; ...

2013-07-22

Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. As a result, low neutron yields and hot-spot mix mass between 34(–13,+50) ng and 4000(–2970,+17 160) ng are observed.

77 FR 74027 - Winter Use Plan, Final Environmental Impact Statement Amended Record of Decision, Yellowstone...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-12

..., Yellowstone National Park. SUMMARY: Pursuant to Sec. 102(2)(C) of the National Environmental Policy Act of... Wyoming. On December 3, 2012, the Regional Director, Intermountain Region, approved the Amended Record of... online at http://parkplanning.nps.gov/yell . Dated: December 2, 2012. John Wessels, Regional Director...

76 FR 68503 - Winter Use Plan, Final Environmental Impact Statement, Yellowstone National Park, Idaho, Montana...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

... to 318 commercially guided, best available technology snowmobiles and 78 commercially guided... available technology snowmobiles and 78 commercially guided snowcoaches would be allowed in the park per day... and a detailed history of winter use in Yellowstone, is available at http://www.nps.gov/yell/planvisit...

Aspen overstory recruitment in northern Yellowstone National Park during the last 200 years

Treesearch

Eric J. Larsen; William J. Ripple

2001-01-01

Using a monograph provided by Warren (1926) and two sets of aspen increment cores collected in 1997 and 1998, we analyzed aspen overstory recruitment in Yellowstone National Park (YNP) over the past 200 years. We found that successful aspen overstory recruitment occurred on the northern range of YNP from the middle to late 1700s until the 1920s, after which it...

Hotspot detection using image pattern recognition based on higher-order local auto-correlation

NASA Astrophysics Data System (ADS)

Maeda, Shimon; Matsunawa, Tetsuaki; Ogawa, Ryuji; Ichikawa, Hirotaka; Takahata, Kazuhiro; Miyairi, Masahiro; Kotani, Toshiya; Nojima, Shigeki; Tanaka, Satoshi; Nakagawa, Kei; Saito, Tamaki; Mimotogi, Shoji; Inoue, Soichi; Nosato, Hirokazu; Sakanashi, Hidenori; Kobayashi, Takumi; Murakawa, Masahiro; Higuchi, Tetsuya; Takahashi, Eiichi; Otsu, Nobuyuki

2011-04-01

Below 40nm design node, systematic variation due to lithography must be taken into consideration during the early stage of design. So far, litho-aware design using lithography simulation models has been widely applied to assure that designs are printed on silicon without any error. However, the lithography simulation approach is very time consuming, and under time-to-market pressure, repetitive redesign by this approach may result in the missing of the market window. This paper proposes a fast hotspot detection support method by flexible and intelligent vision system image pattern recognition based on Higher-Order Local Autocorrelation. Our method learns the geometrical properties of the given design data without any defects as normal patterns, and automatically detects the design patterns with hotspots from the test data as abnormal patterns. The Higher-Order Local Autocorrelation method can extract features from the graphic image of design pattern, and computational cost of the extraction is constant regardless of the number of design pattern polygons. This approach can reduce turnaround time (TAT) dramatically only on 1CPU, compared with the conventional simulation-based approach, and by distributed processing, this has proven to deliver linear scalability with each additional CPU.

Testing the Efficacy of Global Biodiversity Hotspots for Insect Conservation: The Case of South African Katydids.

PubMed

Bazelet, Corinna S; Thompson, Aileen C; Naskrecki, Piotr

2016-01-01

The use of endemism and vascular plants only for biodiversity hotspot delineation has long been contested. Few studies have focused on the efficacy of global biodiversity hotspots for the conservation of insects, an important, abundant, and often ignored component of biodiversity. We aimed to test five alternative diversity measures for hotspot delineation and examine the efficacy of biodiversity hotspots for conserving a non-typical target organism, South African katydids. Using a 1° fishnet grid, we delineated katydid hotspots in two ways: (1) count-based: grid cells in the top 10% of total, endemic, threatened and/or sensitive species richness; vs. (2) score-based: grid cells with a mean value in the top 10% on a scoring system which scored each species on the basis of its IUCN Red List threat status, distribution, mobility and trophic level. We then compared katydid hotspots with each other and with recognized biodiversity hotspots. Grid cells within biodiversity hotspots had significantly higher count-based and score-based diversity than non-hotspot grid cells. There was a significant association between the three types of hotspots. Of the count-based measures, endemic species richness was the best surrogate for the others. However, the score-based measure out-performed all count-based diversity measures. Species richness was the least successful surrogate of all. The strong performance of the score-based method for hotspot prediction emphasizes the importance of including species' natural history information for conservation decision-making, and is easily adaptable to other organisms. Furthermore, these results add empirical support for the efficacy of biodiversity hotspots in conserving non-target organisms.

Testing the Efficacy of Global Biodiversity Hotspots for Insect Conservation: The Case of South African Katydids

PubMed Central

Bazelet, Corinna S.; Thompson, Aileen C.; Naskrecki, Piotr

2016-01-01

The use of endemism and vascular plants only for biodiversity hotspot delineation has long been contested. Few studies have focused on the efficacy of global biodiversity hotspots for the conservation of insects, an important, abundant, and often ignored component of biodiversity. We aimed to test five alternative diversity measures for hotspot delineation and examine the efficacy of biodiversity hotspots for conserving a non-typical target organism, South African katydids. Using a 1° fishnet grid, we delineated katydid hotspots in two ways: (1) count-based: grid cells in the top 10% of total, endemic, threatened and/or sensitive species richness; vs. (2) score-based: grid cells with a mean value in the top 10% on a scoring system which scored each species on the basis of its IUCN Red List threat status, distribution, mobility and trophic level. We then compared katydid hotspots with each other and with recognized biodiversity hotspots. Grid cells within biodiversity hotspots had significantly higher count-based and score-based diversity than non-hotspot grid cells. There was a significant association between the three types of hotspots. Of the count-based measures, endemic species richness was the best surrogate for the others. However, the score-based measure out-performed all count-based diversity measures. Species richness was the least successful surrogate of all. The strong performance of the score-based method for hotspot prediction emphasizes the importance of including species’ natural history information for conservation decision-making, and is easily adaptable to other organisms. Furthermore, these results add empirical support for the efficacy of biodiversity hotspots in conserving non-target organisms. PMID:27631131

Bifurcation of the Yellowstone plume driven by subduction-induced mantle flow

NASA Astrophysics Data System (ADS)

Kincaid, C.; Druken, K. A.; Griffiths, R. W.; Stegman, D. R.

2013-05-01

The causes of volcanism in the northwestern United States over the past 20 million years are strongly contested. Three drivers have been proposed: melting associated with plate subduction; tectonic extension and magmatism resulting from rollback of a subducting slab; or the Yellowstone mantle plume. Observations of the opposing age progression of two neighbouring volcanic chains--the Snake River Plain and High Lava Plains--are often used to argue against a plume origin for the volcanism. Plumes are likely to occur near subduction zones, yet the influence of subduction on the surface expression of mantle plumes is poorly understood. Here we use experiments with a laboratory model to show that the patterns of volcanism in the northwestern United States can be explained by a plume upwelling through mantle that circulates in the wedge beneath a subduction zone. We find that the buoyant plume may be stalled, deformed and partially torn apart by mantle flow induced by the subducting plate. Using plausible model parameters, bifurcation of the plume can reproduce the primary volcanic features observed in the northwestern United States, in particular the opposite progression of two volcanic chains. Our results support the presence of the Yellowstone plume in the northwestern United States, and also highlight the power of plume-subduction interactions to modify surface geology at convergent plate margins.

The silent mass extinction of insect herbivores in biodiversity hotspots.

PubMed

Fonseca, Carlos Roberto

2009-12-01

Habitat loss is silently leading numerous insects to extinction. Conservation efforts, however, have not been designed specifically to protect these organisms, despite their ecological and evolutionary significance. On the basis of species-host area equations, parameterized with data from the literature and interviews with botanical experts, I estimated the number of specialized plant-feeding insects (i.e., monophages) that live in 34 biodiversity hotspots and the number committed to extinction because of habitat loss. I estimated that 795,971-1,602,423 monophagous insect species live in biodiversity hotspots on 150,371 endemic plant species, which is 5.3-10.6 monophages per plant species. I calculated that 213,830-547,500 monophagous species are committed to extinction in biodiversity hotspots because of reduction of the geographic range size of their endemic hosts. I provided rankings of biodiversity hotspots on the basis of estimated richness of monophagous insects and on estimated number of extinctions of monophagous species. Extinction rates were predicted to be higher in biodiversity hotspots located along strong environmental gradients and on archipelagos, where high spatial turnover of monophagous species along the geographic distribution of their endemic plants is likely. The results strongly support the overall strategy of selecting priority conservation areas worldwide primarily on the basis of richness of endemic plants. To face the global decline of insect herbivores, one must expand the coverage of the network of protected areas and improve the richness of native plants on private lands.

Oxygen isotope and trace element evidence for three-stage petrogenesis of the youngest episode (260-79 ka) of Yellowstone rhyolitic volcanism

NASA Astrophysics Data System (ADS)

Loewen, Matthew W.; Bindeman, Ilya N.

2015-10-01

three-stage geochemical evolution of these most recent Yellowstone rhyolites: (1) repeated batch melting events at the base of a homogenized low-δ18O intracaldera fill resulting in liquidus rhyolite melt and a refractory residue that sequesters feldspar-compatible elements over time. This melting may be triggered by conductive "hot plate" heating by basaltic magma intruding beneath the Yellowstone caldera resulting in contact rhyolitic melt that crystallizes early clinopyroxene and/or sanidine at high temperature. (2) Heterogeneity within individual samples and across flows reflects crystallization of these melts during preeruptive storage of magma at at lower, zircon-saturated temperatures. Compatible behavior and variations of most trace elements within individual lava flows are the result of sanidine, quartz, Fe-Ti oxide, zircon, and chevkinite crystallization at this stage. (3) Internal mixing immediately prior to and/or during eruption disrupts, these compositional gradients in each parental magma body that are preserved as melt domains distributed throughout the lava flows. These results based on the most recent and best-preserved volcanic products from the Yellowstone volcanic system provide new insight into the multiple stages required to generate highly fractionated hot spot and rift-related rhyolites. Our proposed model differs from previous interpretations that extreme Sr and Ba depletion result from long-term crystallization of a single magma body—instead we suggest that punctuated batch melting events generated a sanidine-rich refractory residue and a melt source region progressively depleted in Sr and Ba.

Estimating occupancy in large landscapes: Evaluation of amphibian monitoring in the Greater Yellowstone Ecosystem

Treesearch

William R. Gould; Debra A. Patla; Rob Daley; Paul Stephen Corn; Blake R. Hossack; Robert Bennetts; Charles R. Peterson

2012-01-01

Monitoring of natural resources is crucial to ecosystem conservation, and yet it can pose many challenges. Annual surveys for amphibian breeding occupancy were conducted in Yellowstone and Grand Teton National Parks over a 4-year period (2006-2009) at two scales: catchments (portions of watersheds) and individual wetland sites. Catchments were selected in a stratified...

Mitigation of Hot-Spots in Photovoltaic Systems Using Distributed Power Electronics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olalla, Carlos; Hasan, Md. Nazmul; Deline, Chris

In the presence of partial shading and other mismatch factors, bypass diodes may not offer complete elimination of excessive power dissipation due to cell reverse biasing, commonly referred to as hot-spotting in photovoltaic (PV) systems. As a result, PV systems may experience higher failure rates and accelerated ageing. In this paper, a cell-level simulation model is used to assess occurrence of hot-spotting events in a representative residential rooftop system scenario featuring a moderate shading environment. The approach is further used to examine how well distributed power electronics converters mitigate the effects of partial shading and other sources of mismatch bymore » preventing activation of bypass diodes and thereby reducing the chances of heavy power dissipation and hot-spotting in mismatched cells. The simulation results confirm that the occurrence of heavy power dissipation is reduced in all distributed power electronics architectures, and that submodule-level converters offer nearly 100% mitigation of hot-spotting. In addition, the paper further elaborates on the possibility of hot-spot-induced permanent damage, predicting a lifetime energy loss above 15%. In conclusion, this energy loss is fully recoverable with submodule-level power converters that mitigate hot-spotting and prevent the damage.« less

Mitigation of Hot-Spots in Photovoltaic Systems Using Distributed Power Electronics

DOE PAGES

Olalla, Carlos; Hasan, Md. Nazmul; Deline, Chris; ...

2018-03-23

In the presence of partial shading and other mismatch factors, bypass diodes may not offer complete elimination of excessive power dissipation due to cell reverse biasing, commonly referred to as hot-spotting in photovoltaic (PV) systems. As a result, PV systems may experience higher failure rates and accelerated ageing. In this paper, a cell-level simulation model is used to assess occurrence of hot-spotting events in a representative residential rooftop system scenario featuring a moderate shading environment. The approach is further used to examine how well distributed power electronics converters mitigate the effects of partial shading and other sources of mismatch bymore » preventing activation of bypass diodes and thereby reducing the chances of heavy power dissipation and hot-spotting in mismatched cells. The simulation results confirm that the occurrence of heavy power dissipation is reduced in all distributed power electronics architectures, and that submodule-level converters offer nearly 100% mitigation of hot-spotting. In addition, the paper further elaborates on the possibility of hot-spot-induced permanent damage, predicting a lifetime energy loss above 15%. In conclusion, this energy loss is fully recoverable with submodule-level power converters that mitigate hot-spotting and prevent the damage.« less

Automated hotspot analysis with aerial image CD metrology for advanced logic devices

NASA Astrophysics Data System (ADS)

Buttgereit, Ute; Trautzsch, Thomas; Kim, Min-ho; Seo, Jung-Uk; Yoon, Young-Keun; Han, Hak-Seung; Chung, Dong Hoon; Jeon, Chan-Uk; Meyers, Gary

2014-09-01

Continuously shrinking designs by further extension of 193nm technology lead to a much higher probability of hotspots especially for the manufacturing of advanced logic devices. The CD of these potential hotspots needs to be precisely controlled and measured on the mask. On top of that, the feature complexity increases due to high OPC load in the logic mask design which is an additional challenge for CD metrology. Therefore the hotspot measurements have been performed on WLCD from ZEISS, which provides the benefit of reduced complexity by measuring the CD in the aerial image and qualifying the printing relevant CD. This is especially of advantage for complex 2D feature measurements. Additionally, the data preparation for CD measurement becomes more critical due to the larger amount of CD measurements and the increasing feature diversity. For the data preparation this means to identify these hotspots and mark them automatically with the correct marker required to make the feature specific CD measurement successful. Currently available methods can address generic pattern but cannot deal with the pattern diversity of the hotspots. The paper will explore a method how to overcome those limitations and to enhance the time-to-result in the marking process dramatically. For the marking process the Synopsys WLCD Output Module was utilized, which is an interface between the CATS mask data prep software and the WLCD metrology tool. It translates the CATS marking directly into an executable WLCD measurement job including CD analysis. The paper will describe the utilized method and flow for the hotspot measurement. Additionally, the achieved results on hotspot measurements utilizing this method will be presented.

A simple scaling model for smooth vs. rough bathymetry along hotspot tracks

NASA Astrophysics Data System (ADS)

Orellana Rovirosa, F.; Richards, M. A.

2016-12-01

Oceanic hotspot tracks exhibit a remarkable variety of morphologies, both in terms of volcanic seamounts/ocean islands, as well as broader bathymetric swells. A conspicuous feature is that although most hotspot tracks are characterized by "rough" topography, due mainly to volcanic construction, a number are much "smoother," and likely dominated more by the thermal/dynamic swell and crustal intrusion. Examples of relatively smooth tracks include the Nazca Ridge , Carnegie/Cocos/Galápagos, Walvis Ridge, Rio Grande Rise, Iceland, and Kerguelen and much of the Ninety-east Ridge; contrasting with rough and discontinuous seamount chains such Easter/Sala y Gomez, Tristan-Gough, Louisville, Emperor, and much of the Hawaiian ridge. Previous studies have pointed out the role of age, lithospheric thickness, and the plume strength; on the style of the associated bathymetry. Here, we take a systematic approach that emphasizes remarkable along-track changes from smooth to rough topography, e.g., the rough Sala y Gomez and smooth Nazca Ridge portions of the Easter Island hotspot track. Considering the primary controls to be hotspot swell volume flux Qs, the plate-hotspot relative speed v, and the lithospheric elastic thickness D, we suggest that such transitions are controlled by the dimensionless parameter R = sqrt(Qs / v) / D, which is roughly a measure of the heat available from the plume to the heat necessary to thermally attenuate the overlying lithosphere. For very thin (young) lithosphere, such as at the Galápagos platform, igneous intrusion into the hot, weak lithosphere and lower crust may dominate the topographic expression of the hotspot, whereas older lithosphere will support large volcanoes built from magmas passing through more intact lithosphere. Using data from observational studies on mantle-plume buoyancy fluxes, gravity, bathymetry, and tectonic reconstructions, we show that R is a good predictor of bathymetric style: for R<2 hotspot tracks are rough, and for

Analysis of microstructure-dependent shock dissipation and hot-spot formation in granular metalized explosive

NASA Astrophysics Data System (ADS)

Chakravarthy, Sunada; Gonthier, Keith A.

2016-07-01

Variations in the microstructure of granular explosives (i.e., particle packing density, size, shape, and composition) can affect their shock sensitivity by altering thermomechanical fields at the particle-scale during pore collapse within shocks. If the deformation rate is fast, hot-spots can form, ignite, and interact, resulting in burn at the macro-scale. In this study, a two-dimensional finite and discrete element technique is used to simulate and examine shock-induced dissipation and hot-spot formation within low density explosives (68%-84% theoretical maximum density (TMD)) consisting of large ensembles of HMX (C4H8N8O8) and aluminum (Al) particles (size ˜ 60 -360 μm). Emphasis is placed on identifying how the inclusion of Al influences effective shock dissipation and hot-spot fields relative to equivalent ensembles of neat/pure HMX for shocks that are sufficiently strong to eliminate porosity. Spatially distributed hot-spot fields are characterized by their number density and area fraction enabling their dynamics to be described in terms of nucleation, growth, and agglomeration-dominated phases with increasing shock strength. For fixed shock particle speed, predictions indicate that decreasing packing density enhances shock dissipation and hot-spot formation, and that the inclusion of Al increases dissipation relative to neat HMX by pressure enhanced compaction resulting in fewer but larger HMX hot-spots. Ensembles having bimodal particle sizes are shown to significantly affect hot-spot dynamics by altering the spatial distribution of hot-spots behind shocks.

Hotspots in trauma memories and their relationship to successful trauma-focused psychotherapy: a pilot study.

PubMed

Nijdam, Mirjam J; Baas, Melanie A M; Olff, Miranda; Gersons, Berthold P R

2013-02-01

Imaginal exposure is an essential element of trauma-focused psychotherapies for posttraumatic stress disorder (PTSD). Exposure should in particular focus on the "hotspots," the parts of trauma memories that cause high levels of emotional distress which are often reexperienced. Our aim was to investigate whether differences in the focus on hotspots differentiate between successful and unsuccessful trauma-focused psychotherapies. As part of a randomized trial, 45 PTSD patients completed brief eclectic psychotherapy for PTSD. We retrospectively assessed audio recordings of therapy sessions of 20 patients. Frequency of hotspots and the associated emotions, cognitions, and characteristics were compared for the most successful (n = 10) versus the least successful (n = 10) treatments. The mean number of unique hotspots per patient was 3.20, and this number did not differ between successful and unsuccessful treatments. In successful treatments, however, hotspots were more frequently addressed (r = .48), and they were accompanied by more characteristics of hotspots (r = .39), such as an audible change in affect, indicating medium- to large-sized effects. Repeatedly focusing on hotspots and looking for associated characteristics of hotspots may help clinicians to enhance the efficacy of imaginal exposure for patients who would otherwise show insufficient response to treatment. Copyright © 2013 International Society for Traumatic Stress Studies.

Specific Modifications of Histone Tails, but Not DNA Methylation, Mirror the Temporal Variation of Mammalian Recombination Hotspots

PubMed Central

Zeng, Jia; Yi, Soojin V.

2014-01-01

Recombination clusters nonuniformly across mammalian genomes at discrete genomic loci referred to as recombination hotspots. Despite their ubiquitous presence, individual hotspots rapidly lose their activities, and the molecular and evolutionary mechanisms underlying such frequent hotspot turnovers (the so-called “recombination hotspot paradox”) remain unresolved. Even though some sequence motifs are significantly associated with hotspots, multiple lines of evidence indicate that factors other than underlying sequences, such as epigenetic modifications, may affect the evolution of recombination hotspots. Thus, identifying epigenetic factors that covary with recombination at fine-scale is a promising step for this important research area. It was previously reported that recombination rates correlate with indirect measures of DNA methylation in the human genome. Here, we analyze experimentally determined DNA methylation and histone modification of human sperms, and show that the correlation between DNA methylation and recombination in long-range windows does not hold with respect to the spatial and temporal variation of recombination at hotspots. On the other hand, two histone modifications (H3K4me3 and H3K27me3) overlap extensively with recombination hotspots. Similar trends were observed in mice. These results indicate that specific histone modifications rather than DNA methylation are associated with the rapid evolution of recombination hotspots. Furthermore, many human recombination hotspots occupy “bivalent” chromatin regions that harbor both active (H3K4me3) and repressive (H3K27me3) marks. This may explain why human recombination hotspots tend to occur in nongenic regions, in contrast to yeast and Arabidopsis hotspots that are characterized by generally active chromatins. Our results highlight the dynamic epigenetic underpinnings of recombination hotspot evolution. PMID:25326136

Monitoring the trajectory of urban nighttime light hotspots using a Gaussian volume model

NASA Astrophysics Data System (ADS)

Zheng, Qiming; Jiang, Ruowei; Wang, Ke; Huang, Lingyan; Ye, Ziran; Gan, Muye; Ji, Biyong

2018-03-01

Urban nighttime light hotspot is an ideal representation of the spatial heterogeneity of human activities within a city, which is sensitive to regional urban expansion pattern. However, most of previous studies related to nighttime light imageries focused on extracting urban extent, leaving the spatial variation of radiance intensity insufficiently explored. With the help of global radiance calibrated DMSP-OLS datasets (NTLgrc), we proposed an innovative framework to explore the spatio-temporal trajectory of polycentric urban nighttime light hotspots. Firstly, NTLgrc was inter-annually calibrated to improve the consistency. Secondly, multi-resolution segmentation and region-growing SVM classification were employed to remove blooming effect and to extract potential clusters. At last, the urban hotspots were identified by a Gaussian volume model, and the resulting parameters were used to quantitatively depict hotspot features (i.e., intensity, morphology and centroid dynamics). The result shows that our framework successfully captures hotspots in polycentric urban area, whose Ra2 are over 0.9. Meanwhile, the spatio-temporal dynamics of the hotspot features intuitively reveal the impact of the regional urban growth pattern and planning strategies on human activities. Compared to previous studies, our framework is more robust and offers an effective way to describe hotspot pattern. Also, it provides a more comprehensive and spatial-explicit understanding regarding the interaction between urbanization pattern and human activities. Our findings are expected to be beneficial to governors in term of sustainable urban planning and decision making.

Generation and evolution of hydrothermal fluids at Yellowstone: Insights from the Heart Lake Geyser Basin

NASA Astrophysics Data System (ADS)

Lowenstern, J. B.; Bergfeld, D.; Evans, W. C.; Hurwitz, S.

2012-01-01

We sampled fumaroles and hot springs from the Heart Lake Geyser Basin (HLGB), measured water and gas discharge, and estimated heat and mass flux from this geothermal area in 2009. The combined data set reveals that diverse fluids share an origin by mixing of deep solute-rich parent water with dilute heated meteoric water, accompanied by subsequent boiling. A variety of chemical and isotopic geothermometers are consistent with a parent water that equilibrates with rocks at 205°C ± 10°C and then undergoes 21% ± 2% adiabatic boiling. Measured diffuse CO2 flux and fumarole compositions are consistent with an initial dissolved CO2 concentration of 21 ± 7 mmol upon arrival at the caldera boundary and prior to southeast flow, boiling, and discharge along the Witch Creek drainage. The calculated advective flow from the basin is 78 ± 16 L s-1of parent thermal water, corresponding to 68 ± 14 MW, or ˜1% of the estimated thermal flux from Yellowstone. Helium and carbon isotopes reveal minor addition of locally derived crustal, biogenic, and meteoric gases as this fluid boils and degasses, reducing the He isotope ratio (Rc/Ra) from 2.91 to 1.09. The HLGB is one of the few thermal areas at Yellowstone that approaches a closed system, where a series of progressively boiled waters can be sampled along with related steam and noncondensable gas. At other Yellowstone locations, steam and gas are found without associated neutral Cl waters (e.g., Hot Spring Basin) or Cl-rich waters emerge without significant associated steam and gas (Upper Geyser Basin).

Generation and evolution of hydrothermal fluids at Yellowstone: Insights from the Heart Lake Geyser Basin

USGS Publications Warehouse

Lowenstern, J. B.; Bergfeld, D.; Evans, William C.; Hurwitz, S.

2012-01-01

We sampled fumaroles and hot springs from the Heart Lake Geyser Basin (HLGB), measured water and gas discharge, and estimated heat and mass flux from this geothermal area in 2009. The combined data set reveals that diverse fluids share an origin by mixing of deep solute-rich parent water with dilute heated meteoric water, accompanied by subsequent boiling. A variety of chemical and isotopic geothermometers are consistent with a parent water that equilibrates with rocks at 205°C ± 10°C and then undergoes 21% ± 2% adiabatic boiling. Measured diffuse CO2 flux and fumarole compositions are consistent with an initial dissolved CO2 concentration of 21 ± 7 mmol upon arrival at the caldera boundary and prior to southeast flow, boiling, and discharge along the Witch Creek drainage. The calculated advective flow from the basin is 78 ± 16 L s−1 of parent thermal water, corresponding to 68 ± 14 MW, or –1% of the estimated thermal flux from Yellowstone. Helium and carbon isotopes reveal minor addition of locally derived crustal, biogenic, and meteoric gases as this fluid boils and degasses, reducing the He isotope ratio (Rc/Ra) from 2.91 to 1.09. The HLGB is one of the few thermal areas at Yellowstone that approaches a closed system, where a series of progressively boiled waters can be sampled along with related steam and noncondensable gas. At other Yellowstone locations, steam and gas are found without associated neutral Cl waters (e.g., Hot Spring Basin) or Cl-rich waters emerge without significant associated steam and gas (Upper Geyser Basin).

An Evaluation of the Fixed Hotspot Hypothesis for the Pacific Plate

NASA Astrophysics Data System (ADS)

Wessel, P.; Kroenke, L. W.

2008-12-01

Using geometry and ages from 12 Pacific seamount chains, we recently constructed two new Pacific absolute plate motion models that extend our self-consistent and high-resolution models back to 145 Ma. The WK08-A model maps the full uncertainty in the age progressions into uncertainties in rotation opening angles, yielding a relatively smooth plate motion model. The WK08-G model relaxes the mapping of age uncertainties in order to better isolate secondary geometry changes seen along many co-registered chains. Both models have been used to assess the viability of the fixed hotspot hypothesis in the Pacific. In constructing these models, we found that only a small group of age samples had to be discarded on the grounds that they were discordant with the dominant trends. We were able to connect plate motions for pre- and post-Emperor age intervals by including the Ratak-Gilbert-Ellice, Liliuokalani and Musicians trails in our analysis. However, as no active hotspot locations exist for the older chains their inclusion adds additional model parameters. Both age and geometry misfits increase with age, reflecting the observed increase in age uncertainties and the broader and less distinct nature of the older trails. Paleomagnetic observations from the Emperor seamount chain have been interpreted to suggest that these seamounts must have formed at latitudes significantly more northerly than the present location of the Hawaii hotspot, implying a drifting mantle plume. At the same time, new estimates of the age of the Hawaii- Emperor bend places bend formation at a time of global plate reorganization. We will present a complete analysis of inter-chain distances between coeval radiometric samples from Pacific chains and compare these distances to the inter-hotspot distances at the present time. Significant departures from the current hotspot separations would be direct and unequivocal evidence of motion between the Pacific hotspot reference frame and the spin axis and as such

Finding trans-regulatory genes and protein complexes modulating meiotic recombination hotspots of human, mouse and yeast.

PubMed

Wu, Min; Kwoh, Chee-Keong; Li, Xiaoli; Zheng, Jie

2014-09-11

The regulatory mechanism of recombination is one of the most fundamental problems in genomics, with wide applications in genome wide association studies (GWAS), birth-defect diseases, molecular evolution, cancer research, etc. Recombination events cluster into short genomic regions called "recombination hotspots". Recently, a zinc finger protein PRDM9 was reported to regulate recombination hotspots in human and mouse genomes. In addition, a 13-mer motif contained in the binding sites of PRDM9 is found to be enriched in human hotspots. However, this 13-mer motif only covers a fraction of hotspots, indicating that PRDM9 is not the only regulator of recombination hotspots. Therefore, the challenge of discovering other regulators of recombination hotspots becomes significant. Furthermore, recombination is a complex process. Hence, multiple proteins acting as machinery, rather than individual proteins, are more likely to carry out this process in a precise and stable manner. Therefore, the extension of the prediction of individual trans-regulators to protein complexes is also highly desired. In this paper, we introduce a pipeline to identify genes and protein complexes associated with recombination hotspots. First, we prioritize proteins associated with hotspots based on their preference of binding to hotspots and coldspots. Second, using the above identified genes as seeds, we apply the Random Walk with Restart algorithm (RWR) to propagate their influences to other proteins in protein-protein interaction (PPI) networks. Hence, many proteins without DNA-binding information will also be assigned a score to implicate their roles in recombination hotspots. Third, we construct sub-PPI networks induced by top genes ranked by RWR for various species (e.g., yeast, human and mouse) and detect protein complexes in those sub-PPI networks. The GO term analysis show that our prioritizing methods and the RWR algorithm are capable of identifying novel genes associated with

Probing Hotspot Conditions in Spherically Shock Compressed Matter

NASA Astrophysics Data System (ADS)

Bachmann, Benjamin; Nilsen, J.; Kritcher, A. L.; Swift, D.; Rygg, J. R.; Collins, G. W.; Divol, L.; Falcone, R. W.; Gaffney, J.; Glenzer, S. H.; Hatarik, R.; Hawreliak, J.; Khan, S.; Kraus, D.; Landen, O. L.; Masters, N.; Nagel, S. R.; Pardini, T.; Zimmerman, G.; Doeppner, T.

2015-11-01

We present results of an approach to experimentally determine the conditions in the center of a CD2 sphere that has been compressed to petapascal pressures by spherically converging shocks. By measuring the hotspot size using penumbral imaging, hotspot temperature using two-color spectroscopy, the neutron yield from DD nuclear reactions and the x-ray burn width, we infer average hotspot densities of 43 g/cm3 at 1.6 keV temperature. These conditions correspond to pressures of 4.4 petapascal (44 Gbar) in an ideal gas and 3.5 petapascal from independently performed rad.-hydro. simulations. The experimentally determined neutron yield, temperature and density constrain the EOS in a regime that exceeds previously reported pressures obtained in carbon EOS measurements by three orders of magnitude. The results show a path for constraining the EOS of matter at conditions that have been inaccessible with state-of-the-art experimental EOS techniques. This work was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344 and LDRD Grant 13-ERD-073

Scientific Drilling in the Snake River Plain: Past, Present, and Future

NASA Astrophysics Data System (ADS)

Shervais, J. W.; Hanan, B. B.; Hughes, S. S.; Geist, D.; Vetter, S. K.

2006-12-01

The Snake River-Yellowstone volcanic province has long been linked to the concept of lithospheric drift over a fixed mantle thermal anomaly or hotspot. This concept is reinforced by seismic tomography that images this anomaly to depths around 500 km, but alternative proposals still present a serious challenge. Basaltic volcanism spans a significant age range and basaltic volcanism in the western SRP lies well off the hotspot track and cannot be related directly to the hotspot in any simple way. The plume-track age progression is documented by rhyolite volcanic centers, but even these represent extended time periods that overlap in age with adjacent centers. Scientific drilling projects carried out over the last two decades have made significant contributions to our understanding of both basaltic and rhyolitic volcanism associated with the Snake River-Yellowstone hotspot system. Because these drill holes also intercept sedimentary interbeds or, in the case of the western SRP, thick sections of Pliocene and Pleistocene sediments, they have also contributed to our understanding of basin formation by thermal collapse in the wake of the hotspot passage or by rifting, paleoclimate of the interior west, and groundwater systems in volcanic rocks. Many of these drill holes are associated with the Idaho National Laboratory (INL) in the eastern plain; others were drilled for geothermal or petroleum exploration. The latter include older holes that were not instrumented or logged in detail, but which still provide valuable stratigraphic controls. We focus here on the result of basalt drilling, which have been high-lighted in recent publications. Basaltic volcanism in the Snake River plain is dominated by olivine tholeiites that have major and trace element characteristics of ocean island basalt: the range in MgO is similar to MORB, but Ti, Fe, P, K, Sr, Zr and LREE/HREE ratios are all higher. Recent studies of basalts from the drill holes show that they evolved by fractionation

The U S national parks in international perspective: The Yellowstone model or conservation syncretism?

Treesearch

John Schelhas

2010-01-01

In recent years, international conservation scholars and practitioners have largely dismissed the U.S. national park experience, often termed the “Yellowstone model,” as being too protectionist and exclusionary, and therefore irrelevant and even detrimental to park management and policy in lesser developed countries. A review of the U.S. national park experience finds...

Paleo-drainage basin connectivity predicts evolutionary relationships across three Southeast Asian biodiversity hotspots.

PubMed

de Bruyn, Mark; Rüber, Lukas; Nylinder, Stephan; Stelbrink, Björn; Lovejoy, Nathan R; Lavoué, Sébastien; Tan, Heok Hui; Nugroho, Estu; Wowor, Daisy; Ng, Peter K L; Siti Azizah, M N; Von Rintelen, Thomas; Hall, Robert; Carvalho, Gary R

2013-05-01

Understanding factors driving diversity across biodiversity hotspots is critical for formulating conservation priorities in the face of ongoing and escalating environmental deterioration. While biodiversity hotspots encompass a small fraction of Earth's land surface, more than half the world's plants and two-thirds of terrestrial vertebrate species are endemic to these hotspots. Tropical Southeast (SE) Asia displays extraordinary species richness, encompassing four biodiversity hotspots, though disentangling multiple potential drivers of species richness is confounded by the region's dynamic geological and climatic history. Here, we use multilocus molecular genetic data from dense multispecies sampling of freshwater fishes across three biodiversity hotspots, to test the effect of Quaternary climate change and resulting drainage rearrangements on aquatic faunal diversification. While Cenozoic geological processes have clearly shaped evolutionary history in SE Asian halfbeak fishes, we show that paleo-drainage re-arrangements resulting from Quaternary climate change played a significant role in the spatiotemporal evolution of lowland aquatic taxa, and provide priorities for conservation efforts.

29 years of surprises from hotspots: A personal perspective

NASA Astrophysics Data System (ADS)

Students Of Eao, .; Okal, E. A.

2003-12-01

I arrived at Caltech on 26 August 1974, to begin my graduate studies at the Seismo Lab, then under the Directorship of Don L. Anderson. These were the days, among other topics, of Don's famous multilingual footnote on the "definition..., antecedents..., supporters and detractors" of the concept of "plume" [GSA Bull., 86, p. 1593, 1975], and even though I was not to set foot on a hotspot island until my first trip to Tahiti in December 1977 (those stopovers at Keflavik on the 199-dollar Loftleidir runs did not really count), I quickly acquired a mild form of Don's contagious fascination for the activity and structure of hotspots. As a tribute to Don, I have chosen to recap here a few surprising results obtained, with the help of my students, past and present, over several decades of work on the seismological sources and structures in the neighborhood of hotspot islands.

Environmental and Microbial Features Affecting Denitrification and Anammox Hotspots in an Estuarine Ecosystem

NASA Astrophysics Data System (ADS)

Lisa, J.; Song, B.; Lefcheck, J. S.; Tobias, C. R.

2016-02-01

Biogeochemical hotspots are characterized as a few sites that exhibit extremely high reaction rates relative to surrounding area, and often account for a high percentage of the overall reaction rates in an ecosystem. Criteria for quantitatively identifying these sites have not been well established. Further, the underlying mechanisms of hotspots have been described in terms of environmental conditions, with little attention paid to the microbial community. The objectives of this study were to establish quantitative criteria to identify denitrification and anammox hotspots, and determine the underlying microbial and environmental factors responsible for elevated N2 production. We used 15N isotope pairing incubation experiments to measure denitrification and anammox rates in the New River Estuary, NC. Quantitative PCR assays of nitrous oxide reductase (nosZ Clades I and II) and hydrazine oxidoreductase (hzo) genes were conducted to estimate denitrifier and anammox abundance. Structural Equation Modeling (SEM) was used to elucidate complex causal relationships between environmental and biological variables. Denitrification hotspots, quantitatively defined as statistical outliers, accounted for 35.6% total denitrification while comprising only 7.3% of the sites. Anammox hotspots,10.6% of the sites, accounted for 60.9% of total anammox. SEM revealed increased sediment organics at lower salinities supported higher functional gene abundance, which in turn resulted in higher N2 production. Surprisingly, denitrification rates were significantly and positively correlated with nosZ Clade II gene abundance, after accounting for the non-significant contributions of the naturally more abundant nosZ Clade I, and other environmental covariates. This is the first time that a quantitative definition of biogeochemical hotspots was put forth and used to determine the importance of anammox and denitrification hotspots in estuarine nitrogen removal capacity. Despite the low area

Hotspot detection using space-time scan statistics on children under five years of age in Depok

NASA Astrophysics Data System (ADS)

Verdiana, Miranti; Widyaningsih, Yekti

2017-03-01

Some problems that affect the health level in Depok is the high malnutrition rates from year to year and the more spread infectious and non-communicable diseases in some areas. Children under five years old is a vulnerable part of population to get the malnutrition and diseases. Based on this reason, it is important to observe the location and time, where and when, malnutrition in Depok happened in high intensity. To obtain the location and time of the hotspots of malnutrition and diseases that attack children under five years old, space-time scan statistics method can be used. Space-time scan statistic is a hotspot detection method, where the area and time of information and time are taken into account simultaneously in detecting the hotspots. This method detects a hotspot with a cylindrical scanning window: the cylindrical pedestal describes the area, and the height of cylinder describe the time. Cylinders formed is a hotspot candidate that may occur, which require testing of hypotheses, whether a cylinder can be summed up as a hotspot. Hotspot detection in this study carried out by forming a combination of several variables. Some combination of variables provides hotspot detection results that tend to be the same, so as to form groups (clusters). In the case of infant health level in Depok city, Beji health care center region in 2011-2012 is a hotspot. According to the combination of the variables used in the detection of hotspots, Beji health care center is most frequently as a hotspot. Hopefully the local government can take the right policy to improve the health level of children under five in the city of Depok.

The history, hotspots, and trends of electrocardiogram

PubMed Central

Yang, Xiang-Lin; Liu, Guo-Zhen; Tong, Yun-Hai; Yan, Hong; Xu, Zhi; Chen, Qi; Liu, Xiang; Zhang, Hong-Hao; Wang, Hong-Bo; Tan, Shao-Hua

2015-01-01

The electrocardiogram (ECG) has broad applications in clinical diagnosis and prognosis of cardiovascular disease. Many researchers have contributed to its progressive development. To commemorate those pioneers, and to better study and promote the use of ECG, we reviewed and present here a systematic introduction about the history, hotspots, and trends of ECG. In the historical part, information including the invention, improvement, and extensive applications of ECG, such as in long QT syndrome (LQTS), angina, and myocardial infarction (MI), are chronologically presented. New technologies and applications from the 1990s are also introduced. In the second part, we use the bibliometric analysis method to analyze the hotspots in the field of ECG-related research. By using total citations and year-specific total citations as our main criteria, four key hotspots in ECG-related research were identified from 11 articles, including atrial fibrillation, LQTS, angina and MI, and heart rate variability. Recent studies in those four areas are also reported. In the final part, we discuss the future trends concerning ECG-related research. The authors believe that improvement of the ECG instrumentation, big data mining for ECG, and the accuracy of diagnosis and application will be areas of continuous concern. PMID:26345622

The making of a productivity hotspot in the coastal ocean.

PubMed

Wingfield, Dana K; Peckham, S Hoyt; Foley, David G; Palacios, Daniel M; Lavaniegos, Bertha E; Durazo, Reginaldo; Nichols, Wallace J; Croll, Donald A; Bograd, Steven J

2011-01-01

Highly productive hotspots in the ocean often occur where complex physical forcing mechanisms lead to aggregation of primary and secondary producers. Understanding how hotspots persist, however, requires combining knowledge of the spatio-temporal linkages between geomorphology, physical forcing, and biological responses with the physiological requirements and movement of top predators. Here we integrate remotely sensed oceanography, ship surveys, and satellite telemetry to show how local geomorphology interacts with physical forcing to create a region with locally enhanced upwelling and an adjacent upwelling shadow that promotes retentive circulation, enhanced year-round primary production, and prey aggregation. These conditions provide an area within the upwelling shadow where physiologically optimal water temperatures can be found adjacent to a region of enhanced prey availability, resulting in a foraging hotspot for loggerhead sea turtles (Caretta caretta) off the Baja California peninsula, Mexico. We have identified the set of conditions that lead to a persistent top predator hotspot, which increases our understanding of how highly migratory species exploit productive regions of the ocean. These results will aid in the development of spatially and environmentally explicit management strategies for marine species of conservation concern.

78 FR 13932 - Yellowstone Valley Railroad, L.L.C.-Discontinuance of Lease and Trackage Rights Operations...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-01

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. AB 991 (Sub-No. 1X)] Yellowstone Valley Railroad, L.L.C.--Discontinuance of Lease and Trackage Rights Operations Exemption--In Richland, Sheridan, Roosevelt, and Daniels Counties, Mont., and McKenzie County, ND On February 11, 2013...

Predation risk, elk, and aspen: tests of a behaviorally mediated trophic cascade in the Greater Yellowstone Ecosystem.

PubMed

Winnie, John A

2012-12-01

Aspen in the Greater Yellowstone Ecosystem are hypothesized to be recovering from decades of heavy browsing by elk due to a behaviorally mediated trophic cascade (BMTC). Several authors have suggested that wolves interact with certain terrain features, creating places of high predation risk at fine spatial scales, and that elk avoid these places, which creates refugia for plants. This hypothesized BMTC could release aspen from elk browsing pressure, leading to a patchy recovery in places of high risk. I tested whether four specific, hypothesized fine-scale risk factors are correlated with changes in current elk browsing pressure on aspen, or with aspen recruitment since wolf reintroduction, in the Daly Creek drainage in Yellowstone National Park, and near two aspen enclosures outside of the park boundary. Aspen were not responding to hypothesized fine-scale risk factors in ways consistent with the current BMTC hypothesis.

Development of a Wireless Network of Temperature Sensors for Yellowstone National Park (USA)

NASA Astrophysics Data System (ADS)

Munday, D. A.; Hutter, T.; Minolli, M.; Obraczka, K.; Manduchi, R.; Petersen, S.; Lowenstern, J. B.; Heasler, H.

2007-12-01

Temperature sensors deployed at Yellowstone clearly document that thermal features can vary in temperature on a variety of timescales and show regional correlations unrelated to meteorological variables such as air temperature. Yellowstone National Park (YNP) staff currently measures temperatures at over 40 thermal features and streams within the park, utilizing USGS stream gaging stations and portable data loggers deployed in geyser basins. The latter measure temperature every 1 to 15 minutes, and the data are physically downloaded after about 30 days. Installation of a wireless sensor network would: 1) save considerable time and effort in data retrieval, 2) minimize lost data due to equipment failure, and 3) provide a means to monitor thermal perturbations in near-real time. To meet this need, we developed a wireless sensor network capable of in-situ monitoring of air and water temperature. Temperature sensors are dispersed as nodes that communicate among themselves and through relays to a single base-station linked to the Internet. The small, weatherproof sensors operate unattended for over six months at temperatures as low as -40°C. Each uses an ultra-low-power Texas Instruments' MSP430 microcontroller and an SD card as mass storage. They are powered by 15Ah, 3.6 v, inert Li-ion batteries and transmit data via 900MHz radio modules with a 1-km range. The initial prototype consists of 4 nodes, and is designed to scale with additional nodes for finer spatial resolution and broader coverage. Temperature measurements are asynchronous from node to node, with intervals as frequent as 30 seconds. Data are stored internally to withstand temporary communication failures; underlying intelligent software is capable of re-routing data through alternative nodes to the base station and a MySQL data archiving system. We also developed a Google-Maps-based, front-end that displays the data, recent trends and sensor locations. The system was tested in the Santa Cruz Mountains

Specific modifications of histone tails, but not DNA methylation, mirror the temporal variation of mammalian recombination hotspots.

PubMed

Zeng, Jia; Yi, Soojin V

2014-10-16

Recombination clusters nonuniformly across mammalian genomes at discrete genomic loci referred to as recombination hotspots. Despite their ubiquitous presence, individual hotspots rapidly lose their activities, and the molecular and evolutionary mechanisms underlying such frequent hotspot turnovers (the so-called "recombination hotspot paradox") remain unresolved. Even though some sequence motifs are significantly associated with hotspots, multiple lines of evidence indicate that factors other than underlying sequences, such as epigenetic modifications, may affect the evolution of recombination hotspots. Thus, identifying epigenetic factors that covary with recombination at fine-scale is a promising step for this important research area. It was previously reported that recombination rates correlate with indirect measures of DNA methylation in the human genome. Here, we analyze experimentally determined DNA methylation and histone modification of human sperms, and show that the correlation between DNA methylation and recombination in long-range windows does not hold with respect to the spatial and temporal variation of recombination at hotspots. On the other hand, two histone modifications (H3K4me3 and H3K27me3) overlap extensively with recombination hotspots. Similar trends were observed in mice. These results indicate that specific histone modifications rather than DNA methylation are associated with the rapid evolution of recombination hotspots. Furthermore, many human recombination hotspots occupy "bivalent" chromatin regions that harbor both active (H3K4me3) and repressive (H3K27me3) marks. This may explain why human recombination hotspots tend to occur in nongenic regions, in contrast to yeast and Arabidopsis hotspots that are characterized by generally active chromatins. Our results highlight the dynamic epigenetic underpinnings of recombination hotspot evolution. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for

Research Spotlight: Extraordinary uplift of Yellowstone caldera

NASA Astrophysics Data System (ADS)

Tretkoff, Ernie

2011-02-01

In Yellowstone National Park, located in Wyoming, Montana, and Idaho, the Yellow­stone caldera, which extends about 40 kilometers by 60 kilometers, began in 2004 a period of accelerated uplift, with rates of uplift as high as 7 centimeters per year. From 2006 to 2009 the uplift rate slowed. Global Positioning System (GPS) and interferometric synthetic aperture radar (InSAR) ground deformation measurements described by Chang et al. show that in the northern caldera, uplift decreased from 7 centimeters per year in 2006 to 5 in 2008 and 2 in 2009. In the southwestern portion of the caldera, uplift decreased from 4 centimeters per year in 2006 to 2 in 2008 and 0.5 in 2009, demonstrating a spatial pattern of ground motion decrease from southwest to northeast along the caldera. (”Geophysical Research Letters, doi:10.1029/2010GL045451, 2010)

Investigation of a Modern Incipient Stromatolite from Obsidian Pool Prime, Yellowstone National Park: Implications for Early Lithification in the Formation of Light-Dark Stromatolite Laminae

NASA Astrophysics Data System (ADS)

Corsetti, F. A.; Berelson, W.; Pepe-Ranney, C. P.; Mata, S. A.; Spear, J. R.

2016-12-01

Stromatolites have been defined multiple ways, but the presence of lamination is common to all definitions. Despite this commonality, the origin of the lamination in many ancient stromatolites remains vague. Lamination styles vary, but sub-mm light-dark couplets are common in many ancient stromatolites. Here, we investigate an actively forming incipient stromatolite from Obsidian Pool Prime (OPP), a hot spring in Yellowstone National Park, to better understand the formation of light-dark couplets similar to many ancient stromatolites in texture and structure. In the OPP stromatolites, a dense network of layer-parallel bundles of cyanobacterial filaments (a dark layer) is followed by an open network of layer-perpendicular or random filaments (a light layer) that reflect a diurnal cycle in the leading edge of the microbial mat that coats the stromatolite's surface. Silica crust encases the cyanobacterial filaments maintaining the integrity of the lamination. Bubbles formed via oxygenic photosynthesis are commonly trapped within the light layers, indicating that lithification occurs rapidly before the bubbles can collapse. The filamentous, non-heterocystous stromatoite-building cyanobacterium from OPP is most closely related to a stromatolite-building cyanobacterium from a hot spring in Japan. Once built, "tenants" from multiple microbial phyla move into the structure, mixing and mingling to produce a complicated integrated biogeochemical signal that may be difficult to untangle in ancient examples. While the cyanobacterial response to the diurnal cycle has been previously implicated in the formation of light-dark couplets, the OPP example highlights the importance of early lithification in maintaining the fabric. Thus, the presence of light-dark couplets and bubble structures may indicate very early lithification and therefore a certain degree of mineral saturation in the ancient ocean or other aquatic system, and that bubble structures, if present, may be evidence

Threats from Climate Change to Terrestrial Vertebrate Hotspots in Europe

PubMed Central

Maiorano, Luigi; Amori, Giovanni; Capula, Massimo; Falcucci, Alessandra; Masi, Monica; Montemaggiori, Alessandro; Pottier, Julien; Psomas, Achilleas; Rondinini, Carlo; Russo, Danilo; Zimmermann, Niklaus E.

2013-01-01

We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21st century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran’s I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation. PMID:24066162

Threats from climate change to terrestrial vertebrate hotspots in Europe.

PubMed

Maiorano, Luigi; Amori, Giovanni; Capula, Massimo; Falcucci, Alessandra; Masi, Monica; Montemaggiori, Alessandro; Pottier, Julien; Psomas, Achilleas; Rondinini, Carlo; Russo, Danilo; Zimmermann, Niklaus E; Boitani, Luigi; Guisan, Antoine

2013-01-01

We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21(st) century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran's I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation.

Current plate velocities relative to the hotspots incorporating the NUVEL-1 global plate motion model

NASA Technical Reports Server (NTRS)

Gripp, Alice E.; Gordon, Richard G.

1990-01-01

The NUVEL-1 model of current global relative plate velocities is presently incorporated into HS2-NUVEL1, a global model for plate velocities relative to hotspots; the results thus obtained are compared with those of the AM1-2 model of hotspot-relative plate velocities. While there are places in which plate velocities relative to the hotspots differ between HS2-NUVEL1 and AM1-2 by tens of degrees in direction and 15 mm/yr in speed, the hotspot Euler vectors differ with 95 percent confidence only for the Arabian and Indian plates. Plates attached to subducting slabs move faster relative to the hotspots than do plates without slabs.

Volatile Emissions from Hot Spring Basin, Yellowstone National Park, USA

NASA Astrophysics Data System (ADS)

Werner, C.; Hurwitz, S.; Bergfeld, D.; Evans, W. C.; Lowenstern, J. B.; Jaworowski, C.; Heasler, H.

2007-12-01

The flux and composition of magmatic volatiles were characterized for Hot Spring Basin (HSB), Yellowstone National Park, in August 2006. Diffuse fluxes of CO2 (228 sites) from thermal soil were elevated, with a population distribution similar to that of other acid-sulfate areas in Yellowstone. Thus the estimated diffuse emission rate at HSB is proportionately larger than other areas due to its large area, and could be as high as 1000 td-1 CO2. The diffuse flux of H2S was only above detection limits at 20 of the 31 sites measured. The estimated diffuse H2S emission rate was ~ 4 td-1. Good correlation exists between the log of CO2 flux and shallow soil temperatures, indicating linked steam and gas upflow in the subsurface. The correlation between CO2 and H2S fluxes is weak, and the CO2 / H2S diffuse flux ratio was higher than in fumarolic ratios of CO2 to H2S. This suggests that various reactions, e.g., native sulfur deposition, act to remove H2S from the original gas stream in the diffuse low- temperature environment. Dissolved sulfate flux through Shallow Creek, which drains part of HSB, was ~ 4 td-1. Comparing dissolved sulfate flux to estimates of primary emission of H2S based on fumarolic gas geochemistry gives first order estimates of the sulfur consumed in surficial or subsurface mineral deposition. Total C and S outputs from HSB are comparable to other active volcanic systems.

Hotspots of species richness, threat and endemism for terrestrial vertebrates in SW Europe

NASA Astrophysics Data System (ADS)

Pascual, López-López; Luigi, Maiorano; Alessandra, Falcucci; Emilio, Barba; Luigi, Boitani

2011-09-01

The Mediterranean basin, and the Iberian Peninsula in particular, represent an outstanding "hotspot" of biological diversity with a long history of integration between natural ecosystems and human activities. Using deductive distribution models, and considering both Spain and Portugal, we downscaled traditional range maps for terrestrial vertebrates (amphibians, breeding birds, mammals and reptiles) to the finest possible resolution with the data at hand, and we identified hotspots based on three criteria: i) species richness; ii) vulnerability, and iii) endemism. We also provided a first evaluation of the conservation status of biodiversity hotspots based on these three criteria considering both existing and proposed protected areas (i.e., Natura 2000). For the identification of hotspots, we used a method based on the cumulative distribution functions of species richness values. We found no clear surrogacy among the different types of hotspots in the Iberian Peninsula. The most important hotspots (considering all criteria) are located in the western and southwestern portions of the study area, in the Mediterranean biogeographical region. Existing protected areas are not specifically concentrated in areas of high species richness, with only 5.2% of the hotspots of total richness being currently protected. The Natura 2000 network can potentially constitute an important baseline for protecting vertebrate diversity in the Iberian Peninsula although further improvements are needed. We suggest taking a step forward in conservation planning in the Mediterranean basin, explicitly considering the history of the region as well as its present environmental context. This would allow moving from traditional reserve networks (conservation focused on "patterns") to considerations about the "processes" that generated present biodiversity.

LDsplit: screening for cis-regulatory motifs stimulating meiotic recombination hotspots by analysis of DNA sequence polymorphisms.