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GEO.416GEO.416 VOLCANOLOGYVOLCANOLOGY I. Physical Nature Of Magmas . 4 Structural State of Silicate Melts . 4 Viscosity . 5 Controls on Viscosity . 5 Silica composition . 6 Temperature . 6 Time . 6 Volatiles . 7 Pressure . 7 Crystal content . 7 Bubble Content . 8 Yield Strength . 8 Specific Heat . 8 Thermal Conductivity . 8 Density . 9 Electrical Conductivity . 9 Seismic Wave Velocities . 9 II. Generation, Rise And Storage Of Magma . 10 Nature of Crust and Upper Mantle . 10 Heat Sources . 11 Mechanisms of Melting . 11 Partial Melting . 11 Segregation and Rise of Magmas Through The Mantle . 12 Rise of Magmas Through Brittle Lithosphere . 13 Flow of Magma . 14 Flow Rates . 14 Nature of Flow Regime . 15 Flow Instabilities . 15 High-Level Reservoirs and Subvolcanic Stocks . 16 III. Eruptive Mechanisms . 18 Opening Of Vents . 18 Mechanisms of Explosive Eruptions . 18 Nature of the Gaseous Eruptive Column . 19 Bubble Nucleation And Growth . 20 Pressure Relations . 20 Ejection Of Pyroclastic Material . 21 Ejection Velocities . 21 Eruption Energy . 22 V. Lava Flows . 23 Volume . 23 Length and Thickness . 23 Velocity of Flow . 24 Discharge Rates . 24 Physical Properties of Lavas . 25 Temperature and Cooling of Lavas . 25 Viscosity . 25 Morphology Of Lava Flows . 26 Pahoehoe Lavas . 26 External Structures of Pahoehoe Lavas . 26 Internal Structures of Pahoehoe Lavas . 27 Aa Lavas . 28 External Structures of Aa Lavas . 28 Block Lava . 29 Internal Structures of Blocky Lavas . 29 Pillow Lava . 30 VI. Volcanic Domes . 31 External Features of Volcanic Domes . 31 Internal Structures of Volcanic Domes . 32 VII. Products Of Volcanic Explosions . 33 Terminology and Classification . 33 Origin . 33 Fragment Size . 33 Airfall Ash Deposits . 35 Dispersal . 36 Structures Of Airfall Deposits . 36 Morphology of Ash Particles . 37 Pyroclastic Flow And Surge Deposits . 37 Relationship to Topography . 38 Flow Units and Cooling Units . 39 Components . 40 Characteristics of Ash-Flow Deposits . 40 Internal Layering . 40 Gas-Escape Structures . 41 Textural Relationships . 41 Segregation of Crystals and Lithics . 42 Temperature Effects . 42 Welding and Compaction . 42 Structures Related to Temperature and Viscosity . ..

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Historic Littoral Cones in Hawaii
Historic Littoral Cones in Hawaii JAMES G. MOORE AND WAYNE U. AULT 1 ABSTRACT: Littoral cones are formed by steam explosions resulting when lava flows enter the sea. Of about 50 littOral cones on the shores of Mauna Loa and Kilauea on the island of Hawaii, three were formed in historic time: 1840, 1868, and 1919. Five new chemical analyses of the glassy ash of the cones and of the feeding lava show that there is no chemical interchange between molten lava and sea water during the brief period they are in contact. The littoral cone ash contains a lower Fe20g / (Fe20g + FeO) ratio than does its feeding lava because drastic chilling reduces the amount of oxidation. A large volume of lava entering the sea (probably more than 50 million cubic yards) is required to produce a littoral cone. All the histOric littOral cones were fed by aa flows. The turbulent character of these flows and the included cooler, solid material allows ingress of sea water to the interior of the flow where it vaporizes and explodes. The cooler, more brittle lava of the aa flows tend to fragment and shatter more readily upon contact with water than does lava of pahoehoe flows. LITfORAL CONES are common features on the three volcanoes (Mauna Kea, Kohala, and Hua shores of the younger volcanoes of Hawaii lalai) of which the island is composed, nor have (Wentworth and Macdonald, 1953:28). These any littOral cones been mapped on any of the cinder cones do not mark the site of a primary other Hawaiian Islands.
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Smithsonian Contributions to the Earth Sciences • Number 12 Serial Publications of the Smithsonian Institution
GRANT HEIKEN aSa-$T?-x-7-0087) AN ATLAS OFVOLCANIC N74-25882 ASH (Wasa) -5 p HC ~e CSCL 08P Unclas G3/13 40342 SMITHSONIAN CONTRIBUTIONS TO THE EARTH SCIENCES • NUMBER 12 SERIAL PUBLICATIONS OF THE SMITHSONIAN INSTITUTION The emphasis upon publications as a means of uuiubing ln ,.w0 dg .... a ...... by the first Secretary of the Smithsonian Institution. In his formal plan for the Insti- tution, Joseph Henry articulated a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge." This keynote of basic research has been adhered to over the years in the issuance of thousands of titles in serial publications under the Smithsonian imprint, com- mencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Annals of Flight Smithsonian Contributions to Anthropology Smithsonian Contributions to Astrophysics Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Studies in History and Technology In these series, the Institution publishes original articles and monographs dealing with the research and collections of its several museums and offices and of profes- sional colleagues at other institutions of learning. These papers report newly acquired facts, synoptic interpretations of data, or original theory in specialized fields. These publications are distributed by mailing lists to libraries, laboratories, and other in- terested institutions and specialists throughout the world. Individual copies may be obtained from the Smithsonian Institution Press as long as stocks are available.
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Puu Mahana Near South Point in Hawaii Is a Primary Surtseyan Ash Ring, Not a Sandhills-Type Littoral Cone!
Pacific Science (1992), vol. 46, no. 1: 1-10 © 1992 by University of Hawaii Press. All rights reserved Puu Mahana Near South Point in Hawaii Is a Primary Surtseyan Ash Ring, Not a Sandhills-type Littoral Cone! GEORGE P. L. WALKER 2 ABSTRACT: Puu Mahana has previously been interpreted to be a littoral cone, formed at a secondary rootless vent where lava flowed from land into the ocean, but a number oflines ofevidence point to it being a remnant ofa Surtseyan tuff ring built on a primary vent. The differences between it and littoral cones are highlighted by a comparison of Puu Mahana with the undoubted littoral cone ofthe Sandhills that was observed to form in the 1840 flank eruption ofKilauea Volcano. Puu Mahana contains abundant lithic debris and accretionary lapilli, absent in the Sandhills deposit. Compared with the Sandhills, the Puu Mahana pyroclastic deposit is finer grained and more poorly sorted, and its juvenile component is less dense and more highly vesiculated. Puu Mahana lies 3 to 4 km offMauna Loa's southwest rift zone. Identification ofit as a primary vent implies that the lower rift zones of Hawaiian volcanoes can be much wider and more diffuse or more mobile than is currently acknowledged. The olivine grains that compose the well-known green-sand beach at Puu Mahana are likely derived from the ash, strongly concentrated and somewhat abraded by wave action. Puu MARANA, A SMALL coastal hill situated 5 occurrence was fully described by Wentworth km northeast of South Point on the island of (1938), who drew a contour map of the cone.
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Volcanism and Volcanoes
Volcanism and Volcanoes • Volcanism is one of the most impressive displays of Earth’s dynamic internal processes. • From a human perspective, volcanism can be a destructive force causing property damage, injuries, fatalities, and atmospheric changes. • From a geologic perspective, volcanism is a constructive process that builds oceanic Redoubt Volcano. Photograph by W. White, U.S. islands, produces Geological Survey, December 18, 1989 oceanic crust, provides parent material for highly productive soils, and releases the gases that formed Earth’s early atmosphere and surface waters. Why Study Volcanism? • Volcanic eruptions affect the atmosphere, hydrosphere, and biosphere locally and sometimes globally. • Volcanism is a major geologic hazard to a significant portion of Earth’s inhabitants. • Volcanism is responsible for much of Earth’s most spectacular scenery. Augustine Volcano. Photograph by M.E. Yount, U.S. Geological Survey, March 31, 1986. First, you need to know a little about Plate Tectonics.. Text: Figure 4.1, pg 107 http://www.geology.sdsu.edu/how_volcanoes_work/Volcan o_tectonic.html Convergent, Divergent and Transform Boundary http://geomaps.wr.usgs.gov/parks/pltec/pltec3.html younger older DIVERGENT BOUNDARY Divergent Plate Boundary Age of the Atlantic oceanic crust. The crust near the continental margins (blue) is about 200 million years old. It gets progressively younger toward the mid-Atlantic ridge, where oceanic crust is forming today. Courtesy of NOAA http://www.geology.sdsu.edu/how_volcanoes_work/Volcan o_tectonic.html Pillow basalts on the south Pacific seafloor -- Courtesy of NOAA. http://www.geology.sdsu.edu/how_volcanoes_work/Volcano_tectonic.html Transform Boundary…earthquakes Convergent Plate Boundary • The Pacific Ring of Fire • the most volcanically active belt on Earth • subduction zone…large ocean trenches Island Arc Volcanic Arc http://www.geology.sdsu.edu/how_volcanoes_work/Volcano_tectonic.html Intraplate Volcanism Mantle plumes on earth Hotspot Volcanism http://www.geology.sdsu.edu/ Figure 4.4 pg.
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Pleistocene Volcanism and Shifting Shorelines at Lake Tahoe, California GEOSPHERE, V
Research Paper GEOSPHERE Pleistocene volcanism and shifting shorelines at Lake Tahoe, California GEOSPHERE, v. 14, no. 2 Winifred Kortemeier1, Andrew Calvert2, James G. Moore2, and Richard Schweickert3 1Western Nevada College, 2201 West College Parkway, Carson City, Nevada 89703, USA doi:10.1130/GES01551.1 2U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA 3Department of Geological Sciences and Engineering, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557, USA 16 figures; 1 table; 1 supplemental file CORRESPONDENCE: [email protected] CITATION: Kortemeier, W., Calvert, A., Moore, J.G., ABSTRACT 1. INTRODUCTION and Schweickert, R., 2018, Pleistocene volcanism and shifting shorelines at Lake Tahoe, California: Geosphere, v. 14, no. 2, p. 812–834, doi:10.1130/ In the northwestern Lake Tahoe Basin, Pleistocene basaltic and trachy Basaltic and trachyandesitic lavas form a small Pleistocene volcanic field GES01551.1. andesitic lavas form a small volcanic field comprising ~1 km3 of lava that of ~1 km3 in the northwestern Lake Tahoe Basin (Fig. 1). Lavas and pyroclastic erupted from seven vents. Most of these lavas erupted subaerially and material erupted from approximately seven vents on both sides of the Truckee Science Editor: Raymond M. Russo produced lava flows. However, where they flowed into an early Lake Tahoe River, the lake outlet. In this study, a succession of basalt and trachyandesitic Associate Editor: Graham D.M. Andrews ( ProtoTahoe), they produced deltas consisting of hydrovolcanic breccias as lavas was mapped, sampled, analyzed, and radiometrically dated to charac- Received 26 April 2017 well as pillow lavas draped downslope, pillow breccias, hyaloclastites, and terize the nature of the volcanism.
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Fluidal-Clast Breccia Generated by Submarine Fire Fountaining, Trooper
Journal of Volcanology and Geothermal Research 109 22001) 339±355 www.elsevier.com/locate/jvolgeores Fluidal-clast breccia generated by submarine ®re fountaining, Trooper Creek Formation, Queensland, Australia K. Simpson, J. McPhie* Centre for Ore Deposit Research, University of Tasmania, G.P.O. Box 252-79, Hobart, Tasmania 7001, Australia Received 25 May 2000; accepted 18 December 2000 Abstract A distinctive monomictic breccia, composed of ¯uidal and blocky basaltic andesite clasts, occurs in a Cambro-Ordovician submarine volcanic succession in northern Queensland, Australia. Associated with this ¯uvial-clast buccia facies are coherent facies and coarse and ®ne breccia facies of the same composition. The ¯uidal-clast breccia facies is internally massive and .250 m thick, varying only in the ratio of ¯uidal clasts to blocky clasts. Fluidal clasts range in size from 2 cm to 170 cm, and have moderately to highly vesicular cores and thick 2up to 1 cm), non-vesicular, formerly glassy rims. Blocky clasts are highly vesicular to non-vesicular, ,2 cm, angular, dominantly equant or splintery in shape and identical in composition to the ¯uidal clasts. The ¯uidal clasts strongly resemble subaerial volcanic bombs and are interpreted to be the products of submarine ®re fountaining of relatively low-viscosity lava. The blocky clasts were mainly derived from disintegration of the ¯uidal clasts, by means of quench fragmentation. Coherent basaltic andesite intercalated with the ¯uidal-clast breccia represents co-genetic lavas, dykes and irregular shallow intrusions. The coarse and ®ne breccia facies is very thickly bedded, monomictic 2basaltic andesite), poorly sorted and clast supported. This facies is inter- preted to have been generated by periodic gravitational collapse of unstable accumulations of the ¯uidal-clast breccia facies.
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Spring 2006 Colorado School of Mines
geophysics Colorado School of Mines Spring 2006 From the Department Head geophysics n spite of the fact that our enrollment is perennially strong and growing, we are Spring 2006 having trouble supplying the high Colorado School of Mines I recruitment demand for our students. It’s a great time to be graduating with a degree in 3 Hot Topics geophysics! In this newsletter, as always, we introduce the activities of our Department by focusing 10 Collaborations on its people – students, faculty, staff, visi- Terry Young tors. What a pleasure to welcome new faculty members Paul Sava and Feng (Suzie) Su this 14 Crossing Borders year, and to have Martin Landrø spend his sabbatical year with us. We have enjoyed watching our students thrive in their internships, study-abroad experiences, summer field 18 Study Abroad camp, research activities, and extracurricular pursuits. A bonus this year was the field venture in Hawaii, organ- 19 Faculty Spotlight ized by our junior class to do geophysical measurements over active lava flow fields. Our international connections are as strong as ever, with both faculty and students cir- 22 Alumni Focus cling the globe, and international students joining us from all over the world. I hope you have as much fun reading the articles about current hot topics, student life, research col- 24 Internships laborations, and much more, as we have had in writing them for you! 26 Visiting Committee 27 Honors & Awards 28 Campus Life 30 Jobs: The Road Less Traveled On Our Cover 31 Graduation 32 Faculty Retreat GP students Dustin Lanci and Kristen Schmidt pose during 2005 Field Camp in Chaffee County, Colorado.
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Hawaii Volcanoes National Park Geologic Resources
National Park Service U.S. Department of the Interior Natural Resource Program Center Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 THIS PAGE: Geologists have long been monitoring the volcanoes of Hawai‘i Volcanoes National Park.k. Here lava cascades during the 1969-1971 Mauna Ulu eruption of Kīlauea Vollcano. Note the Mauna Ullu fountain in tthee background. U.S. Geological Survey Photo by J. B. Judd (12/30/1969). ON THE COVER: Continuously erupting since 1983, Kīllaueaauea Vollcanocano continues to shape Hawai‘i Volcanoes National Park. Photo courtesy Lisa Venture/University of Cincinnati. Hawai‘i Volcanoes National Park Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2009/163 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 December 2009 U.S. Department of the Interior National Park Service Natural Resource Program Center Denver, Colorado The National Park Service, Natural Resource Program Center publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner.
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Durham Research Online
Durham Research Online Deposited in DRO: 27 August 2015 Version of attached le: Accepted Version Peer-review status of attached le: Peer-reviewed Citation for published item: Reynolds, P.R. and Brown, R.J. and Thordarson, T. and Llewellin, E. and Fielding, K. (2015) 'Rootless cone eruption processes informed by dissected tephra deposits and conduits.', Bulletin of volcanology., 77 (9). p. 72. Further information on publisher's website: http://dx.doi.org/10.1007/s00445-015-0958-3 Publisher's copyright statement: The nal publication is available at Springer via http://dx.doi.org/10.1007/s00445-015-0958-3. Additional information: Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full DRO policy for further details. Durham University Library, Stockton Road, Durham DH1 3LY, United Kingdom Tel : +44 (0)191 334 3042 | Fax : +44 (0)191 334 2971 https://dro.dur.ac.uk 1 Rootless cone eruption processes informed by dissected tephra deposits and conduits 2 3 P. Reynolds1*, R. J. Brown1, T. Thordarson2, E.W. Llewellin1, K. Fielding3 4 5 1Department of Earth Sciences, Durham University, Science Labs, Durham, DH1 3LE, UK 6 2Faculty of Earth Sciences and Nordvulk, University of Iceland, Sturlugata 7, 101 Reykjavík, 7 Iceland 8 3Formerly at: Hess Corporation, Level 9, The Adelphi Building, 1-1 John Adam Street, London, 9 WC2N 6AG, UK 10 *Corresponding author: [email protected], +447887863550 11 12 Abstract 13 Rootless cones result from the explosive interaction between lava flows and underlying water- 14 saturated sediment or volcaniclastic deposits.
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Littoral Hydrovolcanic Explosions: a Case Study of Lava-Seawater Interaction at Kilauea Volcano
Joumalof volcanology and geothennal research ELSEVIER Journal of Volcanology and Geothermal Research 75 (1997) 1-17 Littoral hydrovolcanic explosions: a case study of lava-seawater interaction at Kilauea Volcano Tari N. Mattox *, Margaret T. Mangan I Hawaiian Volcano Observatory, U.S. Geological Survey, P.O. Box 51, Hawai'i National Park, H196718, USA ~( Received I October 1995; accepted 6 June 1996 ic 11 .i iI- Abstract c- A variety of hydrovolcanic explosions may occur as basaltic lava flows into the ocean. Observations and measurements lk were made during a two-year span of unusually explosive littoral activity as tube-fed pahoehoe from Kilauea Volcano inundated the southeast coastline of the island of Hawai'i. Our observations suggest that explosive interactions require high 3 entrance fluxes (24m / s) and are most often initiated by collapse of a developing lava delta. Two types of interactions n. were observed. "Open mixing" of lava and seawater occurred when delta collapse exposed the mouth of a severed lava tube re or incandescent fault scarp to wave action. The ensuing explosions produced unconsolidated deposits of glassy lava is 'R fragments or lithic debris. Interactions under "confined mixing" conditions occurred when a lava tube situated at or below In sea level fractured. Explosions ruptured the roof of the tube and produced circular mounds of welded spatter. We estimate a ct water/rock mass ratio of 0.15 for the most common type of littoral explosion and a kinetic energy release of 0.07-1.3 to kJ/kg for the range of events witnessed. or Keywords: littoral cone; explosion phenomenon; lava; pahoehoe; pyrodasts; Kilauea; basalt 0- 3- 1.
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Kilauea Fieldguide Latest.Pdf
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Eruptions of Hawaiian Volcanoes— Past, Present, and Future
Eruptions of Hawaiian Volcanoes— Past, Present, and Future General Information Product 117 U.S. Department of the Interior U.S. Geological Survey Cascades of lava fed by fountains at vent (seen spouting on the skyline) fall more than 75 feet* to fill Ā‘ lo‘i Crater during the 1969–71 Mauna Ulu eruption of Kïlauea Volcano. (USGS photograph by Donald A. Swanson.) *This publication uses English units of measurement. For readers who use metric units, a conversion table is given in the back of the booklet. Cover—Eruption of Kïlauea Volcano, as viewed at dawn on January 30, 1974. Overflows from an active lava lake spill down the flank of the volcanic shield at Mauna Ulu, built by many such overflows since 1969. The height of this shield was nearly 400 feet when the Mauna Ulu eruptions ended in July 1974. (USGS photograph by Robert I. Tilling.) Eruptions of Hawaiian Volcanoes— Past, Present, and Future By Robert I. Tilling, Christina Heliker, and Donald A. Swanson General Information Product 117 First edition, 1987 Reprinted, 1993 Second revised edition, 2010 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Viginia: 2010 Reprinted 2014 This report and any updates to it are available online at: http://pubs.usgs.gov/gip/117/ For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod/ Telephone: 1-888-ASK-USGS For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment: World Wide Web: http://www.usgs.gov/ Telephone: 1-888-ASK-USGS Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S.
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