Knowledge

Segula Volcano

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Segula is made up of overlapping strata of lava flows and pyroclastic deposits, built up from the caldera. Largely built of eruptive material, the stratovolcano is conical and marked by a fissure. Since it is surrounded by lava flows on the north flank and a
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on the southern and eastern flanks and a submarine deposit to the north of the summit which extends for 11 miles (18 km) have very little erosion, making it likely that Segula has erupted in the last few hundred years.
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on the other, the mountain's caldera, or main crater, appears tiny and is therefore very difficult to make out from any photographs. The north side of the island is summarized by sharp
138:, it has not produced any historical eruptions, while barely eroded deposits on the flanks suggest that activity took place at the volcano as late as a couple of hundred years ago. 199:
and a shallow reef which together make accessibility from that side difficult. It has not had a recorded eruption, though numerous deposits of lava flows and other
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lava and pyroclastic material was ejected from the underwater crater, building up over time to break the surface from nearly 350 feet (107 m) underwater.
176: 392: 387: 161:, Segula Volcano is located, along with the other Aleutians, in the Pacific Ocean. It is located in a row of islands which stretch from 397: 377: 338: 265: 231: 108: 226: 175:
and the volcano formed over an underwater land surface which hosts other Aleutian volcanoes such as
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Built on top of a shallow platform, the volcano grew steadily from eruptions, and is composed of
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W.H. Nelson (1956), "Geology of Segula, Davidof and Khvostof Islands, Alaska",
55: 371: 353: 340: 315: 172: 135: 127: 96: 84: 162: 101: 92: 192: 158: 62: 196: 123: 184: 142: 200: 48: 29: 316:"Geology of Segula, Davidof and Khvostof Islands Alaska" 369: 383:Landforms of Aleutians West Census Area, Alaska 122:lies 1,228 miles (1,976 km) westward of 113:Unrecorded, within the last few hundred years 259: 393:Volcanoes of Unorganized Borough, Alaska 262:United States Geological Survey Bulletin 152: 370: 313: 278: 276: 274: 255: 253: 251: 249: 388:Stratovolcanoes of the United States 13: 271: 246: 14: 409: 398:Cinder cones of the United States 378:Volcanoes of the Aleutian Islands 266:United States Geological Survey 232:United States Geological Survey 307: 214: 1: 207: 34:3,783 ft (1,153 m) 7: 10: 414: 227:Alaska Volcano Observatory 107: 90: 78: 73: 54: 43: 38: 28: 23: 18: 289:Global Volcanism Program 294:Smithsonian Institution 222:"Segula - Introduction" 134:of Alaska. An inactive 47:North Pacific, part of 354:52.01528°N 178.13667°E 165:to as far east as the 314:Nelson, W.H. (1959). 153:Geography and geology 145:of flow deposits and 359:52.01528; 178.13667 350: /  24:Highest point 167:Andreanof Islands 117: 116: 405: 365: 364: 362: 361: 360: 355: 351: 348: 347: 346: 343: 330: 329: 327: 325: 320: 311: 305: 304: 302: 300: 280: 269: 268: 257: 244: 243: 241: 239: 218: 132:Aleutian Islands 67:Aleutian Islands 58: 16: 15: 413: 412: 408: 407: 406: 404: 403: 402: 368: 367: 358: 356: 352: 349: 344: 341: 339: 337: 336: 334: 333: 323: 321: 318: 312: 308: 298: 296: 282: 281: 272: 258: 247: 237: 235: 220: 219: 215: 210: 155: 56: 12: 11: 5: 411: 401: 400: 395: 390: 385: 380: 332: 331: 306: 270: 245: 212: 211: 209: 206: 154: 151: 120:Segula Volcano 115: 114: 111: 105: 104: 99: 88: 87: 82: 76: 75: 71: 70: 60: 52: 51: 45: 41: 40: 36: 35: 32: 26: 25: 21: 20: 19:Segula Volcano 9: 6: 4: 3: 2: 410: 399: 396: 394: 391: 389: 386: 384: 381: 379: 376: 375: 373: 366: 363: 317: 310: 295: 291: 290: 285: 279: 277: 275: 267: 263: 256: 254: 252: 250: 233: 229: 228: 223: 217: 213: 205: 202: 198: 194: 188: 186: 182: 178: 174: 173:Segula Island 170: 168: 164: 160: 150: 148: 144: 139: 137: 136:stratovolcano 133: 129: 128:Segula Island 125: 121: 112: 110: 109:Last eruption 106: 103: 100: 98: 94: 89: 86: 85:Stratovolcano 83: 81: 80:Mountain type 77: 72: 68: 64: 61: 59: 53: 50: 46: 42: 37: 33: 31: 27: 22: 17: 335: 322:. Retrieved 309: 299:December 19, 297:. Retrieved 287: 261: 238:December 19, 236:. Retrieved 225: 216: 189: 171: 163:Kiska Island 157:Part of the 156: 140: 119: 118: 102:Aleutian Arc 57:Parent range 357: / 345:178°08′12″E 193:cinder cone 159:Rat Islands 147:pyroclastic 63:Rat Islands 372:Categories 342:52°00′55″N 208:References 149:material. 185:Andesitic 124:Anchorage 91:Volcanic 65:(part of 39:Geography 30:Elevation 284:"Segula" 177:Khvostof 44:Location 324:18 June 181:Davidof 130:in the 126:on the 74:Geology 234:. 2009 201:ejecta 197:cliffs 143:strata 49:Alaska 319:(PDF) 326:2018 301:2009 240:2009 179:and 97:belt 93:arc 374:: 292:. 286:. 273:^ 264:, 248:^ 230:. 224:. 183:. 169:. 328:. 303:. 242:. 95:/ 69:)

Index

Elevation
Alaska
Parent range
Rat Islands
Aleutian Islands
Mountain type
Stratovolcano
arc
belt
Aleutian Arc
Last eruption
Anchorage
Segula Island
Aleutian Islands
stratovolcano
strata
pyroclastic
Rat Islands
Kiska Island
Andreanof Islands
Segula Island
Khvostof
Davidof
Andesitic
cinder cone
cliffs
ejecta
"Segula - Introduction"
Alaska Volcano Observatory
United States Geological Survey

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