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Preliminary Volcano-Hazard Assessment for Hayes Volcano, Alaska

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Preliminary Volcano-Hazard Assessment for Hayes Volcano, Alaska U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Preliminary Volcano-Hazard Assessment for Hayes Volcano, Alaska Open-File Report 02–072 o n O a b c l s e o r V v a a t k o s r a l y A U S S G G This report is preliminary and subject to revision G S D as new data become available. It does not conform - U A F / G I - A to U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. The Alaska Volcano Observatory (AVO) was established in 1988 to monitor dangerous volcanoes, issue eruption alerts, assess volcano hazards, and conduct volcano research in Alaska. The cooperating agencies of AVO are the U.S. Geological Survey (USGS), the University of Alaska Fairbanks Geophysical Institute (UAFGI), and the Alaska Division of Geological and Geophysical Surveys (ADGGS). AVO also plays a key role in notification and tracking eruptions on the Kamchatka Peninsula of the Russian Far East as part of a formal working relationship with the Kamchatkan Volcanic Eruptions Response Team. Cover photograph: Aerial view of Hayes Volcano in the Tordrillo Mountains near Mount Gerdine (highest peak in background). Most of the volcanic cone of Hayes Volcano was destroyed during the most recent eruption of the volcano, about 3,600 years ago. Because the remaining parts of the cone are obscured by glacier ice and snow, identifying the volcano is difficult. Photograph taken by author T.P. Miller, September 1981. Preliminary Volcano-Hazard Assessment for Hayes Volcano, Alaska By Christopher F. Waythomas and Thomas P. Miller U.S. GEOLOGICAL SURVEY Open-File Report 02–072 Alaska Volcano Observatory Anchorage, Alaska 2002 U.S. DEPARTMENT OF THE INTERIOR GALE A. NORTON, Secretary U.S. GEOLOGICAL SURVEY CHARLES G. GROAT, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government Copies of this report can be obtained from either of the following sources: U.S. Geological Survey U.S. Geological Survey Information Services Earth Science Information Center Building 810 4230 University Drive Box 25286, Federal Center Anchorage, AK 99508 Denver, CO 80225–0286 (Tel. 907-786-7011) (Tel. 303-236-7477 or 800-USA-MAP) How to contact the Alaska Volcano Observatory: U.S. Geological Survey 4200 University Drive Anchorage, AK 99508 (Tel. 907-786-7497) (Fax 907-786-7425) (Internet: http://www.avo.alaska.edu) CONTENTS Summary of hazards at Hayes Volcano ................................................................................................................................. 1 Introduction............................................................................................................................................................................ 3 Purpose and scope...................................................................................................................................................... 5 Physical setting of Hayes Volcano ............................................................................................................................. 5 Eruptive activity at Hayes Volcano........................................................................................................................................ 7 Prehistoric eruptive history ........................................................................................................................................ 7 Historical eruptions .................................................................................................................................................... 7 Hazardous phenomena associated with eruptions ................................................................................................................. 7 Volcanic hazards .................................................................................................................................................................... 10 Volcanic-ash clouds.................................................................................................................................................... 10 Volcanic-ash fallout and volcanic bombs................................................................................................................... 12 Lahars, lahar-runout flows, and floods....................................................................................................................... 15 Pyroclastic flows and surges ...................................................................................................................................... 15 Lava-dome collapse ................................................................................................................................................... 19 Debris avalanches....................................................................................................................................................... 19 Directed blasts............................................................................................................................................................ 21 Volcanic gases ............................................................................................................................................................ 21 Lava flows.................................................................................................................................................................. 21 Event frequency and risk at Hayes Volcano .......................................................................................................................... 22 Hazard warning and mitigation ............................................................................................................................................. 23 References cited..................................................................................................................................................................... 25 Glossary ................................................................................................................................................................................. 26 PLATE 1. Preliminary volcano-hazard assessment for Hayes Volcano, Alaska...................................................... [In pocket] FIGURES 1–3. Maps showing location of Hayes Volcano: 1. With respect to historically active volcanoes in Aleutian volcanic arc and southern Alaska ................. 3 2. In south-central Alaska............................................................................................................................ 4 3. In Tordrillo Mountains and showing principal drainages in region ........................................................ 5 4. Photographs showing northwest flank of Hayes Volcano as viewed from Hayes Glacier .................................... 6 5. Generalized geologic map of Hayes Volcano ........................................................................................................ 8 6. Diagram summarizing Holocene volcanic activity at Hayes Volcano................................................................... 9 7. Simplified sketch of stratovolcano and associated hazardous phenomena............................................................ 10 8. Map showing proximal and distal hazard zones at Hayes Volcano ....................................................................... 11 9. Rose diagrams showing average wind directions for south-central and southwestern Alaska.............................. 12 CONTENTS III FIGURES—Continued 10. Map showing probable travel paths of volcanic-ash clouds from Hayes Volcano ................................................ 13 11. Composite satellite image showing areas in south-central Alaska that received tephra fallout associated with 4,400-to-3,600-year-B.P. eruption of Hayes Volcano ............................................................................................ 14 12. Map showing generalized extent of lahar deposits formed during 4,400-to-3,600-year-B.P. eruption of Hayes Volcano........................................................................................................................................................ 16 13. Photograph showing typical outcrop of lahar deposits along Hayes River ........................................................... 17 14. Map showing hazard zonation for lahars, lahar-runout flows, and floods............................................................. 18 15. Photograph showing pyroclastic-flow deposits near terminus of Hayes Glacier ..................................................19 16–18. Maps showing: 16. Hazard zonation for pyroclastic flows..................................................................................................... 20 17. Hazard zonation for directed blasts ......................................................................................................... 22 18. Major air-travel routes in vicinity of Hayes Volcano .............................................................................. 24 TABLE 1. Alaska Volcano Observatory Level-of-Concern color code .................................................................................. 25 CONVERSION FACTORS and VERTICAL DATUM Multiply by To obtain millimeter (mm) 0.03937 inch centimeter (cm) 0.3937 inch meter (m) 3.281 foot kilometer (km) 0.6214 mile square meter (m2) 10.76 square foot cubic meter (m3) 35.31 cubic foot cubic kilometer (km3) 0.2399
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