scholarly journals Removal of the Northern Paleo-Teton Range along the Yellowstone Hotspot Track

Lithosphere ◽  
2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Ryan Thigpen ◽  
Summer J. Brown ◽  
Autumn L. Helfrich ◽  
Rachel Hoar ◽  
Michael McGlue ◽  
...  
Keyword(s):  
North America ◽  
Mountain Range ◽  
Kinematic Modeling ◽  
Mountain Ranges ◽  
Yellowstone Hotspot ◽  
Original Length ◽  
Teton Range ◽  
Geologic Record ◽  
Short Time ◽  
River Plain

Abstract Classically held mechanisms for removing mountain topography (e.g., erosion and gravitational collapse) require 10-100 Myr or more to completely remove tectonically generated relief. Here, we propose that mountain ranges can be completely and rapidly (<2 Myr) removed by a migrating hotspot. In western North America, multiple mountain ranges, including the Teton Range, terminate at the boundary with the relatively low relief track of the Yellowstone hotspot. This abrupt transition leads to a previously untested hypothesis that preexisting mountainous topography along the track has been erased. We integrate thermochronologic data collected from the footwall of the Teton fault with flexural-kinematic modeling and length-displacement scaling to show that the paleo-Teton fault and associated Teton Range was much longer (min. original length 190-210 km) than the present topographic expression of the range front (~65 km) and extended across the modern-day Yellowstone hotspot track. These analyses also indicate that the majority of fault displacement (min. 11.4-12.6 km) and the associated footwall mountain range growth had accumulated prior to Yellowstone encroachment at ~2 Ma, leading us to interpret that eastward migration of the Yellowstone hotspot relative to stable North America led to removal of the paleo-Teton mountain topography via posteruptive collapse of the range following multiple supercaldera (VEI 8) eruptions from 2.0 Ma to 600 ka and/or an isostatic collapse response, similar to ranges north of the Snake River plain. While this extremely rapid removal of mountain ranges and adjoining basins is probably relatively infrequent in the geologic record, it has important implications for continental physiography and topography over very short time spans.

In the Wake of the Yellowstone Hotspot

2000 ◽  
Author(s):  
Robert B. Smith ◽  
Lee J. Siegel
Keyword(s):  
National Park ◽  
Lava Flows ◽  
Snake River Plain ◽  
Snake River ◽  
Earthquake Activity ◽  
Basalt Lava ◽  
Mountain Ranges ◽  
Yellowstone Hotspot ◽  
A Chain ◽  
River Plain

Anyone who drives through southern Idaho on Interstates 84 or 15 must endure hours and hundreds of miles of monotonous scenery: the vast, flat landscape of the Snake River Plain. In many areas, sagebrush and solidified basalt lava flows extend toward distant mountain ranges, while in other places, farmers have cultivated large expanses of volcanic soil to grow Idaho’s famous potatoes. Southern Idaho’s topography was not always so dull. Mountain ranges once ran through the region. Thanks to the Yellowstone hotspot, however, the pre-existing scenery was destroyed by several dozen of the largest kind of volcanic eruption on Earth—eruptions that formed gigantic craters, known as calderas, measuring a few tens of miles wide. Some 16.5 million years ago, the hotspot was beneath the area where Oregon, Nevada, and Idaho meet. It produced its first big caldera-forming eruptions there. As the North American plate of Earth’s surface drifted southwest over the hotspot, about 100 giant eruptions punched through the drifting plate, forming a chain of giant calderas stretching almost coo miles from the Oregon—Nevada—Idaho border, northeast across Idaho to Yellowstone National Park in northwest Wyoming. Yellowstone has been perched atop the hotspot for the past 2 million years, and a 45-by-30-mile-wide caldera now forms the heart of the national park. After the ancient landscape of southern and eastern Idaho was obliterated by the eruptions, the swath of calderas in the hotspot’s wake formed the eastern two-thirds of the vast, 50-mile-wide valley now known as the Snake River Plain. The calderas eventually were buried by basalt lava flows and sediments from the Snake River and its tributaries, concealing the incredibly violent volcanic history of the Yellowstone hotspot. Yet we now know that the hotspot created much of the flat expanse of the Snake River Plain. Like a boat speeding through water and creating an arc-shaped wave in its wake, the hotspot also left in its wake a parabola-shaped pattern of high mountains and earthquake activity flanking both sides of the Snake River Plain.

Cataclysm!: The Hotspot Reaches Yellowstone

2000 ◽  
Author(s):  
Robert B. Smith ◽  
Lee J. Siegel
Keyword(s):  
North America ◽  
Rhode Island ◽  
Yellowstone National Park ◽  
National Park ◽  
Solid Rock ◽  
Snake River Plain ◽  
Yellowstone Hotspot ◽  
Welded Tuff ◽  
Parallel Lines ◽  
River Plain

Epicenters from numerous earthquakes fall approximately along two parallel lines that stretch from southeast to northwest through Yellowstone National Park. During the past 630,000 years, lava flowed from eruptive vents located roughly along the same lines. The alignment of earthquakes and small volcanoes suggests that zones of weakness are deep beneath them within the Earth. Those zones may be the still-active roots of faults that once ran along the base of towering mountains. Such mountains would have made ancient Yellowstone resemble today’s Grand Teton National Park. Indeed, a few million years ago these mountains may have stretched northward through Yellowstone and hooked up with the Gallatin Range, which now extends from Montana south into Yellowstone’s northwest corner. So why is today’s Yellowstone Plateau relatively flat? What happened to the mountains that once may have rose thousands of feet skyward like the Tetons do today? The answer, quite simply, is that they were destroyed 2 million years ago during a caldera eruption, which is the largest, most catastrophic kind of volcanic outburst—an explosion so cataclysmic that it dwarfs any eruption in historic time. North America had continued its southwestward slide over the Yellowstone hotspot. After blasting and repaving the Snake River Plain, the hotspot was finally beneath the place for which it later was named. The power of its rising heat and hot rock began to shape Yellowstone into what it is today. The first eruptive blast at Yellowstone 2 million years ago left a gigantic hole in the ground—a hole larger than the state of Rhode Island. The huge crater, known as a caldera, measured about 5o miles long, 40 miles wide, and hundreds of yards deep. It extended from Island Park in Idaho to the central part of Yellowstone in Wyoming. During the volcanic cataclysm, hot ash and rock blew into the heavens over Yellowstone, then rained like hell from the sky. As heavier pumice and ash particles debris piled up on the ground, their heat welded the debris together to form a layer of solid rock called ash-flow tuff or welded tuff.

scholarly journals Late Pleistocene glacial chronologies and paleoclimate in the northern Rocky Mountains

2021 ◽  
Author(s):  
Brendon Quirk ◽  
Elizabeth Huss ◽  
Benjamin Laabs ◽  
Eric Leonard ◽  
Joseph Licciardi ◽  
...  
Keyword(s):  
Rocky Mountains ◽  
Ice Sheet ◽  
Northern Rocky Mountains ◽  
Mountain Ranges ◽  
Mountain Glaciers ◽  
Continental Divide ◽  
Ice Retreat ◽  
Geologic Record ◽  
Glacier Modeling ◽  
Exposure Ages

Abstract. The geologic record of mountain glaciations is a robust indicator of terrestrial paleoclimate change. During the last glaciation, mountain ranges across the western U.S. hosted glaciers while the Cordilleran and Laurentide ice sheets flowed to the west and east of the continental divide, respectively. Records detailing the chronologies and paleoclimate significance of these ice advances have been developed for many sites across North America. However, relatively few glacial records have been developed for mountain glaciers in the northern Rocky Mountains near ice sheet margins. Here, we report cosmogenic beryllium-10 surface exposure ages and numerical glacier modeling results showing that mountain glaciers in the northern Rockies abandoned terminal moraines after the end of the Last Glacial Maximum around 17–18 ka and could have been sustained by −10 to −8.5 °C temperature depressions relative to modern assuming similar or drier than modern precipitation. Additionally, we present a deglacial chronology from the northern Rocky Mountains that indicates while there is considerable variability in initial moraine abandonment ages across the Rocky Mountains, the pace of subsequent ice retreat through the Lateglacial exhibits some regional coherence. Our results provide insight on potential regional mechanisms driving the initiation of and sustained deglaciation in the western U.S. including rising atmospheric CO2 and ice sheet collapse.

scholarly journals [Re]covering Jeddah’s Wadis – Building the City’s Resilience through Green Infrastructure

2018 ◽  
Vol 11 (4) ◽  
pp. 228
Author(s):  
Hanaa Motasim
Keyword(s):  
Green Infrastructure ◽  
Rain Water ◽  
Mountain Range ◽  
Water Drainage ◽  
Severe Damage ◽  
Mountain Ranges ◽  
Natural Flow ◽  
The Rich ◽  
The City ◽  
Green Corridors

Jeddah, Saudi Arabia’s largest coastal city, is positioned between two prominent natural features: the mountain range on its eastern side and the Red Sea on its west. The city faces many challenges central to which is storm water drainage. The natural drainage of the city through its pre-existing wadis, bringing down the rain water from the steep mountain ranges through the low inclining coastal plane and into the sea, has been interrupted in the last few decades by massive road infrastructural projects cutting through the city and interrupting the natural flow. The outcome of these interventions has been excessive flooding calamities, of which the ones in 2009 and 2011 were the most extreme, causing severe damage to infrastructure, property and lives.In light of climate change the intensity of flash floods is expected to increase, placing enormous stress on the city. To control the floods the city has pushed forward heavily engineered solutions, canalizing the rich network of wadis, almost 80 in number, into 4 major concrete channels that discharge the rain water accumulated in the mountains directly into the sea. This solution, which has been prohibitive in cost, has robbed the city of any potential of utilizing the precious supply of rain water. This paper explores the potential of recovering Jeddah’s wadis and creating green corridors across the city. As opposed to engineered solutions which address singular problematics, green infrastructures could provide numerous benefits to the city and the region as a whole.

Paleoecology and Late Quaternary Environments of the Colorado Rockies

2001 ◽  
Author(s):  
Scott A. Elias
Keyword(s):  
North America ◽  
Late Quaternary ◽  
Ice Sheets ◽  
Ice Sheet ◽  
Rocky Mountain ◽  
Mountain Region ◽  
Ice Age ◽  
Rocky Mountain Region ◽  
Last Ice Age ◽  
Teton Range

Present-day environments cannot be completely understood without knowledge of their history since the last ice age. Paleoecological studies show that the modern ecosystems did not spring full-blown onto the Rocky Mountain region within the last few centuries. Rather, they are the product of a massive reshuffling of species that was brought about by the last ice age and indeed continues to this day. Chronologically, this chapter covers the late Quaternary Period: the last 25,000 years. During this interval, ice sheets advanced southward, covering Canada and much of the northern tier of states in the United States. Glaciers crept down from mountaintops to fill high valleys in the Rockies and Sierras. The late Quaternary interval is important because it bridges the gap between the ice-age world and modern environments and biota. It was a time of great change, in both physical environments and biological communities. The Wisconsin Glaciation is called the Pinedale Glaciation in the Rocky Mountain region (after terminal moraines near the town of Pinedale, Wyoming; see chapter 4). The Pinedale Glaciation began after the last (Sangamon) Interglaciation, perhaps 110,000 radiocarbon years before present (yr BP), and included at least two major ice advances and retreats. These glacial events took different forms in different regions. The Laurentide Ice Sheet covered much of northeastern and north-central North America, and the Cordilleran Ice Sheet covered much of northwestern North America. The two ice sheets covered more than 16 million km2 and contained one third of all the ice in the world’s glaciers during this period. The history of glaciation is not as well resolved for the Colorado Front Range region as it is for regions farther north. For instance, although a chronology of three separate ice advances has been established for the Teton Range during Pinedale times, in northern Colorado we know only that there were earlier and later Pinedale ice advances. We do not know when the earlier advance (or multiple advances) took place. However, based on geologic evidence (Madole and Shroba 1979), the early Pinedale glaciation was more extensive than the late Pinedale was.

scholarly journals First interception of the greenhouse pest Echinothrips americanus Morgan, 1913 (Thysanoptera: Thripidae) in Slovakia

2009 ◽  
Vol 44 (No. 4) ◽  
pp. 155-159 ◽  
Author(s):  
L. Varga ◽  
P.J. Fedor
Keyword(s):  
North America ◽  
Host Range ◽  
Botanical Garden ◽  
European Countries ◽  
Pest Species ◽  
Wide Host Range ◽  
Short Time ◽  
And Control

<i>Echinothrips americanus</i> Morgan, 1913, is one of the pest species that expanded their area of distribution in a relatively short time. Being native to the eastern parts of North America, its first European interception was recorded in 1989. Since then it has invaded greenhouses in most European countries, including Slovakia, where it was first recorded in inspected material at the Botanical garden in Košice. As a polyphagous thrips with a wide host range it may induce damage mainly on ornamentals, although if low in numbers it can be easily overlooked. The species is a suitable example where preventive steps against its spread have not been sufficient enough which, therefore, demands further monitoring. Remarks on morphology, identification, economical importance and control are also given.

scholarly journals Impact of North Atlantic Oscillation on the Snowpack in Iberian Peninsula Mountains

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 105 ◽  
Author(s):  
Esteban Alonso-González ◽  
Juan I. López-Moreno ◽  
Francisco M. Navarro-Serrano ◽  
Jesús Revuelto
Keyword(s):  
North Atlantic Oscillation ◽  
Iberian Peninsula ◽  
Sierra Nevada ◽  
North Atlantic ◽  
Snow Water Equivalent ◽  
Mountain Range ◽  
Winter Climate ◽  
Mountain Ranges ◽  
Iberian Range ◽  
The Impact

The North Atlantic Oscillation (NAO) is considered to be the main atmospheric factor explaining the winter climate and snow evolution over much of the Northern Hemisphere. However, the absence of long-term snow data in mountain regions has prevented full assessment of the impact of the NAO at the regional scales, where data are limited. In this study, we assessed the relationship between the NAO of the winter months (DJFM-NAO) and the snowpack of the Iberian Peninsula. We simulated temperature, precipitation, and snow data for the period 1979–2014 by dynamic downscaling of ERA-Interim reanalysis data, and correlated this with the DJFM-NAO for the five main mountain ranges of the Iberian Peninsula (Cantabrian Range, Central Range, Iberian Range, the Pyrenees, and the Sierra Nevada). The results confirmed that negative DJFM-NAO values generally occur during wet and mild conditions over most of the Iberian Peninsula. Due to the direction of the wet air masses, the NAO has a large influence on snow duration and the annual peak snow water equivalent (peak SWE) in most of the mountain ranges in the study, mostly on the slopes south of the main axis of the ranges. In contrast, the impact of NAO variability is limited on north-facing slopes. Negative (positive) DJFM-NAO values were associated with longer (shorter) duration and higher (lower) peak SWEs in all mountains analyzed in the study. We found marked variability in correlations of the DJFM-NAO with snow indices within each mountain range, even when only the south-facing slopes were considered. The correlations were stronger for higher elevations in the mountain ranges, but geographical longitude also explained the intra-range variability in the majority of the studied mountains.

scholarly journals THE NORTH AMERICAN SPECIES OF PEDILOPHORUS

1903 ◽  
Vol 35 (6) ◽  
pp. 179-182
Author(s):  
H. F. Wickham
Keyword(s):  
North America ◽  
North American ◽  
North American Species ◽  
The West ◽  
Mountain Ranges ◽  
The North

The Byrrhidæ of this continent have received a comparatively small share of attention at the hands of systematists for many years, so that it is not at all surprising to find novelties among recently-collected material. Two new forms of the genus Pedilophorus have recently been detected among the accumulations in my cabinet, both of them from the west; no doubt still others remain to reward explorers of the mountain ranges and of the northern districts. The European fauna contains ten species, while but four were previously known from North America.

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