660:|b=50|l=en|t=4001|zf=0.0|ms=sel_00dec|dw=17.701027675209602|dh=6.035539041852557|dt=gov.census.aff.domain.map.EnglishMapExtent|if=gif|cx=-170.20089635341083|cy=63.430295928031335|zl=8|pz=8|bo=318:317:316:314:313:323:319|bl=362:393:358:357:356:355:354|ft=350:349:335:389:388:332:331|fl=381:403:204:380:369:379:368|g=04000US02&-PANEL_ID=p_dt_geo_map&-_lang=en&-geo_id=100$ 10000US020160001001132&-CONTEXT=dt&-format=&-search_results=100$ 10000US020500001001047&-ds_name=DEC_2000_SF1_U Bobrof Island: Block 1132, Census Tract 1, Aleutians West Census Area, Alaska
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288:. Bobrof Island is 2.6 miles (4.2 km) long and 1.8 miles (2.9 km) wide with an area of 3 square miles (7.8 km), and consists primarily of the 2,421-foot (738 m) high Bobrof Volcano. The volcanic crater, or cone, has been heavily dissected. Underwater deposits adjacent to the island's northeast flank suggest an immense debris-avalanche has taken place.
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Because of the inclusion of Alaska, the United States has the largest number of active volcanoes in the world, many of them geologically young. In Alaska, at least 50 volcanoes, including those in the
Aleutian archipelago, have erupted in historical time. Alaska accounts for about 80% of the United
335:. Once these flows were studied, at a building intended for earthquake monitoring, they confirmed that Bobrof was prone to explosive activity. There are lava deposits on the mountain which also suggest activity similar to
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The volcano is thought to be of
Holocene age. Though no historical eruptions have taken place at Bobrof, it has erupted at least once. This data can be confirmed through pyroclastic flow deposits containing
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in the area, about 8% of the world's volcanoes, and most of these are located among the
Aleutian Islands. The Aleutian Islands arc forms the northern boundary of the
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485:"Reconnaissance geology of some western Aleutian Islands, Alaska: in Investigations of Alaskan volcanoes, U.S. Geological Survey Bulletin B 1028-E"
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which forms the small Bobrof Island. No recorded eruptions have taken place at Bobrof or in its vicinity. It has been considered as
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629:"The geology, geochemistry and petrology of the recent magmatic phase of the central and western Aleutian Arc"
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347:. No complete publications exist for Bobrof's definite geology, just those with facts and some information.
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514:"The National Volcano Early Warning System (NVEWS): U.S. Geological Survey Fact Sheet FS 2006-3142"
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280:. Bobrof Island is a small, uninhabited island about 9 miles (14 km) north and west of
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Ewert, John; Guffanti, Marianne; Cervelli, Peter; Quick, James (2006).
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339:. In collected samples, there are traces of
429:. Fairbanks: Alaska Native Language Center.
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675:Photographs from Bobrof Island, July 2008
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1350:Mountains of Unorganized Borough, Alaska
1345:Volcanoes of Unorganized Borough, Alaska
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594:"Bobrof description and statistics"
394:Geographic Names Information System
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544:"Alaska GeoSurvey News: NL 2008-1"
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27:Island in the U.S. state of Alaska
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319:States' volcanoes, excluding the
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604:United States Geological Survey
518:United States Geological Survey
492:United States Geological Survey
399:United States Geological Survey
34:Nautical Chart of Bobrof Island
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1335:Uninhabited islands of Alaska
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80:Bobrof Island and the volcano
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662:United States Census Bureau
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599:Alaska Volcano Observatory
124:51.9083333°N 177.4388889°W
96:2,421 ft (738 m)
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455:Global Volcanism Program
365:"Bobrof Volcano, Alaska"
129:51.9083333; -177.4388889
460:Smithsonian Institution
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184:North Pacific, part of
571:Cite journal requires
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782:Anangula (Ananiuliak)
636:University of Wyoming
627:Myers, J. D. (1994).
314:Geography and geology
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673:Bobrof Island Photos
325:Pacific Ring of Fire
58:class=notpageimage|
1330:Volcanoes of Alaska
1289:Walrus and Kritskoi
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1325:Inactive volcanoes
1112:Tufted Puffin Rock
86:Highest point
61:Location in Alaska
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1360:Islands of Alaska
1310:Andreanof Islands
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1172:Walrus (Pribilof)
341:basaltic andesite
266:Andreanof Islands
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272:in southwestern
270:Aleutian Islands
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286:Tanaga Island
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282:Kanaga Island
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278:United States
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229:Stratovolcano
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1072:St. Lawrence
997:Pancake Rock
872:Great Sitkin
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639:. Retrieved
607:. Retrieved
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564:cite journal
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194:Parent range
1082:St. Michael
1077:St. Matthew
877:Hagemeister
212:Age of rock
127: /
115:177°26′20″W
102:Coordinates
1304:Categories
927:Karaginsky
917:Kamen Ariy
847:Chuginadak
711:Bering Sea
408:2011-08-08
374:2011-08-08
351:References
112:51°54′30″N
1244:Krenitzin
1219:Commander
1209:Andreanof
1012:Sagchudak
932:Kasatochi
907:Kagalaska
762:Amatignak
321:seamounts
235:Volcanic
140:Geography
92:Elevation
1259:Pribilof
1204:Aleutian
1182:Yttygran
1147:Unalaska
1087:St. Paul
957:Kritskoi
937:Khvostof
842:Chagulak
837:Carlisle
827:Bogoslof
802:Avatanak
767:Amchitka
641:July 10,
609:July 10,
497:July 10,
483:(1956).
465:July 10,
450:"Bobrof"
425:(1994).
333:andesite
308:Holocene
301:inactive
217:Holocene
181:Location
1249:Kudobin
1229:Diomede
1224:Delarof
1187:Yunaska
1107:Tigalda
1097:Tagalak
1037:Sedanka
1017:Samalga
987:Oglodak
982:Nunivak
952:Koniuji
912:Kagamil
897:Igitkin
892:Herbert
887:Hawadax
867:Gareloi
817:Besboro
757:Amaknak
554:July 9,
523:July 9,
206:Geology
1284:Walrus
1177:Wislow
1167:Walrus
1162:Unimak
1132:Uliaga
1122:Ugidak
1117:Ugamak
1102:Tanaga
1092:Stuart
1067:Sledge
1062:Skagul
1057:Shemya
1047:Segula
1042:Seguam
1007:Rootok
977:Nelson
922:Kanaga
857:Derbin
852:Chugul
832:Buldir
822:Bobrof
812:Bering
777:Amukta
747:Akutan
737:Aiktak
732:Agattu
727:Adugak
345:dacite
299:is an
274:Alaska
186:Alaska
171:Alaska
1274:Sanak
1264:Punuk
1142:Umnak
1022:Sanak
992:Otter
972:Medny
947:Kiska
807:Aziak
772:Amlia
632:(PDF)
488:(PDF)
310:age.
262:Walĝa
258:Aleut
1279:Seal
1254:Near
1214:Baby
1137:Umak
1127:Ulak
942:King
902:Ilak
882:Hall
797:Attu
792:Atka
752:Amak
742:Akun
722:Adak
643:2009
611:2009
577:help
556:2009
525:2009
499:2009
467:2009
343:and
241:belt
1269:Rat
1239:Fox
1002:Poa
862:Egg
237:arc
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
