DOCSLIB.ORG

Tracking Changes in Yellowstone's Restless Volcanic System

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Tracking Changes in Yellowstone's Restless Volcanic System U.S. GEOLOGICAL SURVEY and the NATIONAL PARK SERVICE—OUR VOLCANIC PUBLIC LANDS Tracking Changes in Yellowstone’s Restless Volcanic System The world-famous Yellowstone geysers and hot springs are In the 1970s, a resurvey of benchmarks discovered the fueled by heat released from an unprecedented uplift of the enormous reservoir of magma Yellowstone Caldera of more (partially molten rock beneath than 28 inches (72 cm) over fi ve decades. More recently, the ground). Since the 1970’s, new and revolutionary sat- scientists have tracked rapid ellite-based methods for tracking the Earth’s shifting uplift and subsidence of the ground motions have en- ground and signifi cant changes abled University of Utah, U.S. Geological Survey, and other in hydrothermal (hot water) scientists to assemble a more features and earthquake activity. precise and detailed picture of Yellowstone’s ground In 2001, the Yellowstone Volcano movements. Global Position- Observatory was created by the ing System (GPS) stations like U.S. Geological Survey (USGS), this one in the Norris Geyser Basin can detect changes in the University of Utah, and elevation and horizontal shifts Yellowstone National Park to of 1 inch or less per year, helping scientists understand strengthen scientists’ ability to the processes that drive track activity that could result in Yellowstone’s active volcanic and earthquake systems. hazardous seismic, hydrothermal, (Photo courtesy of Christine or volcanic events in the region. Puskas, University of Utah.) No actual volcanic eruption has occurred in this way, the water level of Yellowstone Lake lowstone Caldera, a shallow, oval depression, the Yellowstone National Park region of Wyo- would appear to rise at the south end. 53 miles long and 28 miles across (85 by 45 ming, Montana, and Idaho since a lava fl ow To test this idea, in 1975–77 scientists from km), in the middle of the park. This caldera poured out about 70,000 years ago. However, the University of Utah and the U.S. Geo- was formed 640,000 years ago during the the area’s many geysers and hot springs indi- logical Survey (USGS) resurveyed a series of most recent of Yellowstone’s great volcanic cate that the underlying volcanic system re- benchmarks along roads throughout Yellow- eruptions. In that eruption, 240 cubic miles mains active. In the early 1970’s, Earth scien- stone National Park. These benchmarks were (1,000 km3) of molten rock (magma) was tists found evidence that this system was more originally installed and their elevations and blasted into the atmosphere and scattered on active than even these spectacular hydrother- locations precisely determined in 1923. The the Earth’s surface—more than 1,000 times mal (hot water) features had suggested. results of the resurvey showed dramatically the volume erupted at Mount St. Helens in One important clue was found along the that the central part of the park had indeed 1980! The ground then collapsed into the south shore of Yellowstone Lake, where trees risen. The greatest uplift appeared to be in the partly emptied magma reservoir, forming an were dying because their trunks were partly area of Le Hardy Rapids on the Yellowstone enormous craterlike depression. below water and a boat dock had become River, a few miles downstream from the lake’s Later eruptions of many large lava fl ows, completely submerged. At the same time, the outlet. There the ground had risen 28.5 inches some as thick as 400 feet (120 m), buried the water level at the lake’s outlet on its north side (72 cm) since 1923, raising the nearby north original caldera fl oor and most of the caldera appeared little changed. end of Yellowstone Lake much more than the walls. Mount Washburn, a prominent land- Scientists reasoned that these observations south end. Scientists then focused their atten- mark in the park, is a section of the caldera could be explained by southward tilt of the tion on what could be causing the ground to rim that escaped burial. The most recent area around Yellowstone Lake, including the rise and whether the uplift was still going on. series of eruptions at Yellowstone, 160,000 to lake basin itself. If the entire area was being 70,000 years ago, covered much of the cal- pushed up, perhaps the ground at the north Yellowstone Caldera and its resurgent domes dera fl oor with more than 20 thick lava fl ows, end of the lake was rising more than the south The 1975–77 survey showed that the area including the Elephant Back fl ow, which can end, like a giant bathtub lifted at one end. In of recent uplift was located within the Yel- be seen west of Fishing Bridge. U.S. Department of the Interior USGS Fact Sheet 100-03 U.S. Geological Survey 2004 111°W 110.5° 110° The uplift detected in the 1970’s was cen- tered near Le Hardy Rapids, between two resurgent domes—sections of the caldera fl oor that had earlier been pushed upward and faulted. Such resurgent domes form when magma rises to shallow levels beneath 45°N a caldera and slowly reinfl ates a previously depleted magma reservoir, pushing the over- lying caldera fl oor upward to form a dome. The pressure of the infl ating magma reser- Mount Washburn voir may even force some of the molten rock M to emerge at the surface as lava. The fact that the uplift documented in t Y Sour Creek the 1970’s was centered within the caldera Dome LeHardyRapids near the resurgent domes seemed to indi- Fishing B cate that the magma reservoir was again 44.5° Mallard exerting pressure upward. What could be Lake Dome Yellowstone causing this? Was new magma entering Yel- Lake lowstone’s enormous reservoir from below? Perhaps volcanic gas was escaping from the magma reservoir, percolating upward and era causing the surface to bow upward? Perhaps some of Yellowstone’s hot water had become trapped beneath the surface, exerting pres- sure on the caldera fl oor from below? New volcano-monitoring data soon forced scien- 44° tists to think again about what was occurring beneath Yellowstone’s active caldera. The region of Yellowstone National Park in Wyoming, Montana, and Idaho is famous for its spec- tacular geysers and extensive hot springs, indications that an underlying volcanic system remains The ups and downs of the caldera’s movements active. The central part of the park is occupied by the great, partly fi lled depression of the Yellow- To learn more about the changing ground stone Caldera, formed in a giant volcanic eruption 640,000 years ago that blasted 240 cubic miles levels in the Yellowstone area, scientists con- (1,000 km3) of molten rock (magma) into the atmosphere—more than 1,000 times the volume erupted at Mount St. Helens in 1980. Later eruptions largely fi lled the caldera and pushed up two resurgent ducted additional surveys across the eastern domes within it—the Sour Creek and Mallard Lake Domes. No actual volcanic eruption has oc- part of the caldera nearly every year from curred in the Yellowstone region for about 70,000 years. However, since the 1970’s, scientists have 1983 to 1998. In the 1990’s, new and revolu- detected signifi cant changes in this remarkable volcanic and hydrothermal (hot water) system, including rapid ground uplift and subsidence and bursts of earthquake activity. tionary satellite-based methods for tracking the Earth’s changing ground surface—the Global Positioning System (GPS) and In- -111.5° -111° -110.5° -110° terferometric Synthetic Aperture Radar (In- SAR)—were applied by University of Utah, A new satellite-based tech- USGS, and other scientists to assemble a more 45° nique known as Interferomet- ric Synthetic Aperture Radar detailed picture of how and when the ground (InSAR) allows direct and moves above Yellowstone’s magma reservoir. precise measurement of the These new data reveal that Yellowstone is vertical changes in ground level. This InSAR image of the in nearly continuous but frequently changing area around the Yellowstone movement—the fl oor of the caldera contin- Caldera (dotted line) shows ued to rise until 1984, stopped rising during vertical changes during the 4-year period 1996–2000. 1984–85, and then subsided for the next 10 ° 44.5 The ringed pattern centered years. Parts of the central caldera began rising northwest of Yellowstone again in 1995, but a more complex pattern Lake is a prominent area of dome-shaped uplift. Each of uplift and subsidence has prevailed since complete cycle of colors in 2000. InSAR data show that between 1995 the color bands represents a and 1997 a large area along the northwest little more than one inch (28.3 mm) of vertical change. Yellow rim of the Yellowstone Caldera, centered near triangles are continuous GPS Norris Geyser Basin, started to rise. The pic- 0 28.3 mm 44° 01020MILES stations; white dots are loca- ture that emerges from all these data is of a Range Change tions of earthquakes in the 01020KILOMETERS period 1996–2000. dynamic system in which the caldera fl oor is in almost constant motion—episodes of uplift 1000 14,000 THE YELLOWSTONE 900 12,000 Diagrammatic caldera subsidence VOLCANO OBSERVATORY 800 (averag Increased scientifi c surveillance of 700 e 19 mm/yr) 10,000 Diagrammatic caldera uplift Yellowstone in the past 30 years has erage 22 mm/yr) R (av eturn to 600 Autumn 1985 swarm p t artial uplif 8,000 detected unmistakable changes in its 500 akes vast underground volcanic system, hqu art e e 6,000 similar to historical changes observed 400 ulativ Cum No at many other large calderas (vol- 300 seismic 4,000 data canic depressions) in the world.
Load more

Recommended publications
  • The Track of the Yellowstone Hot Spot: Volcanism, Faulting, and Uplift
    Geological Society of America Memoir 179 1992 Chapter 1 The track of the Yellowstone hot spot: Volcanism, faulting, and uplift Kenneth L. Pierce and Lisa A. Morgan US. Geological Survey, MS 913, Box 25046, Federal Center, Denver, Colorado 80225 ABSTRACT The track of the Yellowstone hot spot is represented by a systematic northeast-trending linear belt of silicic, caldera-forming volcanism that arrived at Yel- lowstone 2 Ma, was near American Falls, Idaho about 10 Ma, and started about 16 Ma near the Nevada-Oregon-Idaho border. From 16 to 10 Ma, particularly 16 to 14 Ma, volcanism was widely dispersed around the inferred hot-spot track in a region that now forms a moderately high volcanic plateau. From 10 to 2 Ma, silicic volcanism migrated N54OE toward Yellowstone at about 3 cm/year, leaving in its wake the topographic and structural depression of the eastern Snake River Plain (SRP). This <lo-Ma hot-spot track has the same rate and direction as that predicted by motion of the North American plate over a thermal plume fixed in the mantle. The eastern SRP is a linear, mountain- bounded, 90-km-wide trench almost entirely(?) floored by calderas that are thinly cov- ered by basalt flows. The current hot-spot position at Yellowstone is spatially related to active faulting and uplift. Basin-and-range faults in the Yellowstone-SRP region are classified into six types based on both recency of offset and height of the associated bedrock escarpment. The distribution of these fault types permits definition of three adjoining belts of faults and a pattern of waxing, culminating, and waning fault activity.
    [Show full text]
  • Educators Guide
    EDUCATORS GUIDE 02 | Supervolcanoes Volcanism is one of the most creative and destructive processes on our planet. It can build huge mountain ranges, create islands rising from the ocean, and produce some of the most fertile soil on the planet. It can also destroy forests, obliterate buildings, and cause mass extinctions on a global scale. To understand volcanoes one must first understand the theory of plate tectonics. Plate tectonics, while generally accepted by the geologic community, is a relatively new theory devised in the late 1960’s. Plate tectonics and seafloor spreading are what geologists use to interpret the features and movements of Earth’s surface. According to plate tectonics, Earth’s surface, or crust, is made up of a patchwork of about a dozen large plates and many smaller plates that move relative to one another at speeds ranging from less than one to ten centimeters per year. These plates can move away from each other, collide into each other, slide past each other, or even be forced beneath each other. These “subduction zones” are generally where the most earthquakes and volcanoes occur. Yellowstone Magma Plume (left) and Toba Eruption (cover page) from Supervolcanoes. 01 | Supervolcanoes National Next Generation Science Standards Content Standards - Middle School Content Standards - High School MS-ESS2-a. Use plate tectonic models to support the HS-ESS2-a explanation that, due to convection, matter Use Earth system models to support cycles between Earth’s surface and deep explanations of how Earth’s internal and mantle. surface processes operate concurrently at different spatial and temporal scales to MS-ESS2-e form landscapes and seafloor features.
    [Show full text]
  • R. L. Smith, H. R. Shaw, R. G. Luedke, and S. L. Russell U. S. Geological
    COMPREHENSIVE TABLES GIVING PHYSICAL DATA AND THERMAL ENERGY ESTIMATES FOR YOUNG IGNEOUS SYSTEMS OF THE UNITED STATES by R. L. Smith, H. R. Shaw, R. G. Luedke, and S. L. Russell U. S. Geological Survey OPEN-FILE REPORT 78-925 This report is preliminary and has not been edited or reviewed for conformity with Geological Survey Standards and nomenclature INTRODUCTION This report presents two tables. The first is a compre­ hensive table of 157 young igneous systems in the western United States, giving locations, physical data, and thermal en­ ergy estimates, where apropriate, for each system. The second table is a list of basaltic fields probably less than 10,000 years old in the western United States. These tables are up­ dated and reformatted from Smith and Shaw's article "Igneous- related geothermal systems" in Assessment of geothermal re­ sources of the United States 1975 (USGS Circular 726, White and Williams, eds., 1975). This Open-File Report is a compan­ ion to Smith and Shaw's article "Igneous-related geothermal systems" in Assessment of geothermal resources in the United States 1978 (USGS Circular 790, Muffler, ed., 1979). The ar­ ticle in Circular 790 contains an abridged table showing only those igneous systems for which thermal estimates were made. The article also gives an extensive discussion of hydrothermal cooling effects and an explanation of the model upon which the thermal energy estimates are based. Thermal energy is calculated for those systems listed in table 1 that are thought to contribute significant thermal en­ ergy to the upper crust. As discussed by Smith and Shaw (1975), silicic volcanic systems are believed to be associated nearly always with high-level (<10 km) magma chambers.
    [Show full text]
  • Plate Tectonics and the Rock Cycle
    Lab 2: Plate Tectonics Lab 2: Plate Tectonics and the Rock Cycle Introduction Plate tectonics is a fundamental concept that connects many aspects of modern geology. Outer portions of the Earth are broken into tectonic plates, which are continually moving, colliding, and being pushed on top of (or underneath) each other. Plates are composed of three kinds of rocks: igneous, sedimentary, and metamorphic. These types of rocks are commonly found in specific parts of the plates. During this lab you will become familiar with features related to tectonic plate activity, such as earthquakes, volcanoes, mountains, and oceans. You will examine the movement of some plates, and think about what kind of rocks are associated with specific types of tectonic settings. A. Plate Tectonics Earth’s structure can be classified by chemical composition or by physical properties (Figure 2-1). The chemical layers of the Earth are the crust, mantle, and core. The crust is largely comprised of igneous rocks: continental crust is made of felsic (silica-rich) rocks like granite, and oceanic crust is made of mafic (silica-poor) rocks such as basalt. Below the crust is the mantle, which is made of minerals that are rich in iron and magnesium, and at Earth’s center is the iron-nickel core. The physical layers that are most important for plate tectonics are the lithosphere and the asthenosphere. Tectonic plates are pieces of the lithosphere, which is a layer of brittle rock that corresponds to the crust and the upper mantle. The asthenosphere corresponds to the lower mantle, and it is hot enough to be ductile rather than rigid.
    [Show full text]
  • Controls on Thermal Discharge in Yellowstone National Park, Wyoming
    University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2007 CONTROLS ON THERMAL DISCHARGE IN YELLOWSTONE NATIONAL PARK, WYOMING Jacob Steven Mohrmann The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Mohrmann, Jacob Steven, "CONTROLS ON THERMAL DISCHARGE IN YELLOWSTONE NATIONAL PARK, WYOMING" (2007). Graduate Student Theses, Dissertations, & Professional Papers. 1239. https://scholarworks.umt.edu/etd/1239 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. CONTROLS ON THERMAL DISCHARGE IN YELLOWSTONE NATIONAL PARK, WYOMING By Jacob Steven Mohrmann B.A. Environmental Science, Northwest University, Kirkland, WA, 2003 Thesis presented in partial fulfillment of the requirements for the degree of Masters of Science in Geology The University of Montana Missoula, MT Fall 2007 Approved by: Dr. David A. Strobel, Dean Graduate School Dr. Nancy Hinman Committee Chair Dr. William Woessner Committee Member Dr. Solomon Harrar Committee Member Mohrmann, Jacob, M.S., Fall 2007 Geology Controls on Thermal Discharge in Yellowstone National Park, Wyoming Director: Nancy W. Hinman Significant fluctuations in discharge occur in hot springs in Yellowstone National Park on a seasonal to decadal scale (Ingebritsen et al., 2001) and an hourly scale (Vitale, 2002). The purpose of this study was to determine the interval of the fluctuations in discharge and to explain what causes those discharge patterns in three thermally influenced streams in Yellowstone National Park.
    [Show full text]
  • Geophysical and Geochemical Signals at Yellowstone and Other Large Caldera Systems
    Phil. Trans. R. Soc. A (2006) 364, 2055–2072 doi:10.1098/rsta.2006.1813 Published online 27 June 2006 Monitoring super-volcanoes: geophysical and geochemical signals at Yellowstone and other large caldera systems 1, 2 1 BY JACOB B. LOWENSTERN *,ROBERT B. SMITH AND DAVID P. HILL 1US Geological Survey, Volcano Hazards Team, MS 910, 345 Middlefield Road, Menlo Park, CA 94025, USA 2Department of Geology and Geophysics, University of Utah, 135 South, 1460 East, Room 702, Salt Lake City, UT 84112, USA Earth’s largest calderas form as the ground collapses during immense volcanic eruptions, when hundreds to thousands of cubic kilometres of magma are explosively withdrawn from the Earth’s crust over a period of days to weeks. Continuing long after such great eruptions, the resulting calderas often exhibit pronounced unrest, with frequent earthquakes, alternating uplift and subsidence of the ground, and considerable heat and mass flux. Because many active and extinct calderas show evidence for repetition of large eruptions, such systems demand detailed scientific study and monitoring. Two calderas in North America, Yellowstone (Wyoming) and Long Valley (California), are in areas of youthful tectonic complexity. Scientists strive to understand the signals generated when tectonic, volcanic and hydrothermal (hot ground water) processes intersect. One obstacle to accurate forecasting of large volcanic events is humanity’s lack of familiarity with the signals leading up to the largest class of volcanic eruptions. Accordingly, it may be difficult to recognize the difference between smaller and larger eruptions. To prepare ourselves and society, scientists must scrutinize a spectrum of volcanic signals and assess the many factors contributing to unrest and toward diverse modes of eruption.
    [Show full text]
  • DOGAMI Open-File Report O-83-03, Survey of Potential Geothermal
    DOE/BP/272 STATE OF OREGON DEPARTMENT OF GEOLOGY AND MINERAL INDUSTRIES 1005 State Office Building Portland, Oregon 97201 OPEN-FILE REPORT 0-83-3 SURVEY OF POTENTIAL GEOTHERMAL EXPLORATION SITES AT NEWBERRY VOLCANO, DESCHUTES COUNTY, OREGON 1983 edited by George R. Priest, Beverly F. Vogt, and Gerald L. Black, Oregon Department of Geology and Mineral Industries This work was supported by the Bonneville Power Administration under Cooperative Agreement No. DE-AC79-82BP36734. Governi Board State Geologist Allen P. St·inchfield, Chairman, North Bend Donald A. Hull Donald A. Haagensen, Portland Sidney R. Johnson, Baker Deputy State Geologist John D. Beaulieu NOTICE The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Reference herein to any specific commercial product, process, or service by trade name, mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. NOTICE The Oregon Department of Geology and Mineral Industries is publishing this paper because the subject matter is consistent with the mission of the Department. To facilitate timely distribution of information, this paper ~as not been edited to our usual standards. ii CONTENTS CHAPTER 1. EXECUTIVE SUMMARY, by George R. Priest 1 Introduction 1 Objectives 1 Methodology 1 Assumptions 2 Conclusions 2 Acknowledgments 4 CHAPTER 2. GEOLOGY OF THE NEWBERRY VOLCANO AREA, DESCHUTES COUNTY, OREGON, by George R. Priest 5 Introduction . 5 Genera 1 Geo 1 ogy . 5 Results of USGS Drilling Program 10 Geophysical Evidence for a Shallow Intrusive 12 Distribution of Volcanic Centers: Implications for the Lateral Extent of a Silicic Intrusive Body 13 Caldera Geometry: Implications for Depths to Former Magma Chambers .
    [Show full text]
  • Protocols for Geologic Hazards Response by the Yellowstone Volcano Observatory
    Prepared in cooperation with Yellowstone National Park, the University of Utah, the University of Wyoming, the Idaho Geological Survey, the Montana Bureau of Mines and Geology, the Wyoming State Geological Survey, and UNAVCO Protocols for Geologic Hazards Response by the Yellowstone Volcano Observatory Circular 1351 Version 2.0, November 2014 U.S. Department of the Interior U.S. Geological Survey Cover: Images clockwise from upper left: Schematic organization of an Incident Command incorporating Yellowstone Volcano Observatory. University of Utah and Yellowstone National Park staff during wintertime equipment deployment. Example of data routing for monitoring data from Yellowstone Seismic Network. Logo of Yellowstone Volcano Observatory. Protocols for Geologic Hazards Response by the Yellowstone Volcano Observatory By the Yellowstone Volcano Observatory Circular 1351 Version 2.0, November 2014 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia First release: 2010 Revised and reprinted: November 2014 (ver. 2.0) For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1–888–ASK–USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Suggested citation: Yellowstone Volcano Observatory, 2014, Protocols for geologic hazards response by the Yellowstone Volcano Observatory (ver. 2.0, November 2014): U.S.
    [Show full text]
  • Fluvial Geomorphic and Hydrologic Evolution and Climate Change Resilience in Young Volcanic Landscapes: Rhyolite Plateau and Lamar Valley, Yellowstone National Park
    University of New Mexico UNM Digital Repository Earth and Planetary Sciences ETDs Electronic Theses and Dissertations Summer 7-15-2020 Fluvial Geomorphic and Hydrologic Evolution and Climate Change Resilience in Young Volcanic Landscapes: Rhyolite Plateau and Lamar Valley, Yellowstone National Park Benjamin Newell Burnett University of New Mexico Follow this and additional works at: https://digitalrepository.unm.edu/eps_etds Part of the Geology Commons, Geomorphology Commons, and the Hydrology Commons Recommended Citation Burnett, Benjamin Newell. "Fluvial Geomorphic and Hydrologic Evolution and Climate Change Resilience in Young Volcanic Landscapes: Rhyolite Plateau and Lamar Valley, Yellowstone National Park." (2020). https://digitalrepository.unm.edu/eps_etds/275 This Dissertation is brought to you for free and open access by the Electronic Theses and Dissertations at UNM Digital Repository. It has been accepted for inclusion in Earth and Planetary Sciences ETDs by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected], [email protected], [email protected]. i Benjamin Newell Burnett Candidate Earth and Planetary Sciences Department This dissertation is approved, and it is acceptable in quality and form for publication: Approved by the Dissertation Committee: Dr. Grant Meyer , Chairperson Dr. Peter Fawcett Dr. Leslie McFadden Dr. Julia Coonrod ii FLUVIAL GEOMORPHIC AND HYDROLOGIC EVOLUTION AND CLIMATE CHANGE RESILIENCE IN YOUNG VOLCANIC LANDSCAPES: RHYOLITE PLATEAU AND LAMAR VALLEY,
    [Show full text]
  • Future Volcanism at Yellowstone Caldera: Insights from Geochemistry of Young Volcanic Units and Monitoring of Volcanic Unrest
    2012 Annual Meeting & Exposition Issue! SEPTEMBER 2012 | VOL. 22, NO. 9 A PUBLICATION OF THE GEOLOGICAL SOCIETY OF AMERICA® Future volcanism at Yellowstone caldera: Insights from geochemistry of young volcanic units and monitoring of volcanic unrest Inside: Preliminary Announcement and Call for Papers: 2013 GSA Northeastern Section Meeting, p. 38 Preliminary Announcement and Call for Papers: 2013 GSA Southeastern Section Meeting, p. 41 VOLUME 22, NUMBER 9 | 2012 SEPTEMBER SCIENCE ARTICLE GSA TODAY (ISSN 1052-5173 USPS 0456-530) prints news and information for more than 25,000 GSA member read- ers and subscribing libraries, with 11 monthly issues (April/ May is a combined issue). GSA TODAY is published by The Geological Society of America® Inc. (GSA) with offices at 3300 Penrose Place, Boulder, Colorado, USA, and a mail- ing address of P.O. Box 9140, Boulder, CO 80301-9140, USA. 4 Future volcanism at Yellowstone GSA provides this and other forums for the presentation of diverse opinions and positions by scientists worldwide, caldera: Insights from geochemistry regardless of race, citizenship, gender, sexual orientation, of young volcanic units and religion, or political viewpoint. Opinions presented in this monitoring of volcanic unrest publication do not reflect official positions of the Society. Guillaume Girard and John Stix © 2012 The Geological Society of America Inc. All rights reserved. Copyright not claimed on content prepared Cover: View looking west into the Midway geyser wholly by U.S. government employees within the scope of basin of Yellowstone caldera (foreground) and the West their employment. Individual scientists are hereby granted permission, without fees or request to GSA, to use a single Yellowstone rhyolite lava flow (background).
    [Show full text]
  • Yellowstone National Park Resources and Issues: Geology
    The landscape of Yellowstone National Park is the result of many geological processes. Here, glacial erratics (foreground), ground moraines (midground), and Cutoff Mountain (background) appear near Junction Butte. Geology GEOLOGY The landscape of the Greater Yellowstone Ecosystem miles in diameter) is extremely hot but solid due to is the result various geological processes over the last immense pressure. The iron and nickel outer core 150 million years. Here, Earth’s crust has been com- (1,400 miles thick) is hot and molten. The mantle pressed, pulled apart, glaciated, eroded, and subjected (1,800 miles thick) is a dense, hot, semi-solid layer to volcanism. This geologic activity formed the moun- of rock. Above the mantle is the relatively thin crust, tains, canyons, plateaus, and hydrothermal features three to 48 miles thick, forming the continents and that define the natural wonder that is Yellowstone. ocean floors. While these mountains and canyons may appear In the key principles of Plate Tectonics, Earth’s to change very little during our lifetime, they are still crust and upper mantle (lithosphere) is divided into highly dynamic and variable. Some of Earth’s most active volcanic, hydrothermal (water + heat), and Yellowstone’s Geologic Signifcance earthquake systems make this national park a price- less treasure. In fact, Yellowstone was established as Yellowstone continues today as a natural geologic the world’s first national park primarily because of laboratory of active Earth processes. its extraordinary geysers, hot springs, mudpots and • One of the most geologically dynamic areas on Earth due to a shallow source of magma and resulting steam vents, as well as other wonders such as the volcanic activity.
    [Show full text]
  • A Hazard Assessment for the San Francisco Volcanic Field, Arizona Aleeza Harburger University of South Florida, [email protected]
    University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 3-7-2014 Probabilistic Modeling of Lava Flows: A Hazard Assessment for the San Francisco Volcanic Field, Arizona Aleeza Harburger University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the Geology Commons, Land Use Law Commons, and the Statistics and Probability Commons Scholar Commons Citation Harburger, Aleeza, "Probabilistic Modeling of Lava Flows: A Hazard Assessment for the San Francisco Volcanic Field, Arizona" (2014). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/5033 This Thesis is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Probabilistic Modeling of Lava Flows: A Hazard Assessment for the San Francisco Volcanic Field, Arizona by Aleeza M. Harburger A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science Department of Geology College of Arts and Sciences University of South Florida Major Professor: Charles Connor, Ph.D. Stephen McNutt, Ph.D. Rocco Malservisi, Ph.D. Date of Approval: March 7, 2014 Keywords: spatial density, Monte Carlo simulation, Flagstaff, natural disaster, monogenetic fields Copyright © 2014, Aleeza M. Harburger Acknowledgments I would like to first and foremost thank my thesis advisor, Dr. Charles B. Connor, for his expert advice, guidance, and encouragement during my research and preparation for this thesis. I would also like to thank my committee members, Dr.
    [Show full text]