Three Sisters (Oregon)

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silicic magma that erupted from 20 vents on the southeast side and from a smaller line on the north side. These eruptions generated pyroclastic flows and lava domes from vents on the northern, southern, eastern, and southeastern sides of the volcano. These relatively recent, postglacial eruptions suggest the presence of a silicic magma reservoir under South Sister, one that could perhaps lead to future eruptions.

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which causes it to become warmer and drier. On the western slopes, precipitation ranges from 80 to 125 in (200 to 320 centimeters) annually, while precipitation over the eastern slopes varies from 40 to 80 in (100 to 200 cm) in the east. Temperature extremes reach 80 to 90 degrees Fahrenheit (27 to 32 degrees Celsius) in summers and −20 to −30 °F (−29 to −34 °C) during the winters.

658:, producing a large mudflow that could endanger wilderness visitors and the town of Sisters. Studies at Collier Lake and Diller Lake suggested that both had breached their dams in the early 1940s and in 1970, respectively. Other moraine-dammed lakes within the wilderness area include Thayer Lake on North Sister's east flank and four members of the Chambers Lakes group between Middle and South Sister. 670:

common in the Deschutes National Forest. In September 2012, a lightning strike caused a fire that burned 41 square miles (110 km) in the Pole Creek area within the Three Sisters Wilderness, leaving the area closed until May 2013. In August 2017, officials closed 417 sq mi (1,080 km) in the western half of the Three Sisters Wilderness, including 24 mi (39 km) of the

991:/rhyodacitic and rhyolitic eruptions. The volcano built a broad andesitic cone, forming a steep summit cone of andesite about 27,000 years ago. South Sister remained dormant for 15,000 years, after which its composition shifted from dacitic to more rhyolitic lava. An eruptive episode about 2,200 years ago, termed the Rock Mesa eruptive cycle, first spread 480:. The three peaks are the third-, fourth-, and fifth-highest in Oregon, and contain 16 named glaciers. Their ice volume totals 5.6 billion cubic feet (160 million cubic metres). The Sisters were named Faith, Hope and Charity by early settlers, but are now known as North Sister, Middle Sister and South Sister, respectively. 933:

events (about 38,000 years ago) produced the rhyolite of Obsidian Cliffs on the mountain's northwestern flank. Thick and rich in dacite, the flows extended from the northern and southern sides. They stand in contrast to older, andesitic lava remains that reach as far as 4.3 mi (7 km) from its base.

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With an elevation of 10,052 ft (3,064 m), the mountain is cone-shaped. The eastern side has been heavily eroded by glaciation, while the western face is mostly intact. Of the Three Sisters, Middle Sister has the largest ice cover. The Hayden and Diller glaciers continue to cut into the east

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In the late 19th century, there was extensive wool production in eastern Oregon. Shepherds led their herds of 1,500 to 2,500 sheep to the Three Sisters. They arrived in eastern foothills near Whychus Creek by May or June, and then climbed to higher pastures in August and September. By the 1890s, the

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A study published in 2010 described the magma intrusion as having a volume of about 2.1 billion cubic feet (59,000,000 m). Scientists determined in 2013 that the uplift had slowed to a rate of about 0.3 inches (7.6 mm) per year, compared to up to 2 in (51 mm) per year in the

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completed an analysis of the Three Sisters vicinity and concluded that Multnomah had never existed, instead demonstrating that each volcano in the area possessed its own individual eruptive history. Williams' 1944 paper defined the basic outline of the Three Sisters vicinity, though he lacked access

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stratovolcano overlying an older shield structure. Its modern structure is no more than 50,000 years old, and it last erupted about 2,000 years ago. Although its first eruptive events from 50,000 to 30,000 years ago were predominantly rhyolitic, between 38,000 and 32,000 years ago the

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Neither North nor Middle Sister is likely to resume volcanic activity. An eruption from South Sister would pose a threat to nearby life, as the proximal danger zone extends 1.2 to 6.2 mi (2 to 10 km) from the volcano's summits. During an eruption, tephra could accumulate to 1 to 2 in

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demonstrate similar compositions throughout the mountain's long eruptive history. The oldest lava flows on North Sister have been dated to roughly 311,000 years ago, though the oldest reliably dated deposits are approximately 119,000 years old. Estimates place the volcano's last eruption at 46,000

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caused by the Cascade Range. Air from the Pacific Ocean rises over the western slopes, which causes it to cool and dump its moisture as rain (or snow in the winter). Precipitation increases with elevation. Once the moisture is wrung from the air, the air descends on the eastern side of the crest,

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When the first geological reconnaissance of the Three Sisters region was published in 1925, its author, Edwin T. Hodge, suggested that the Three Sisters and five smaller mountains in the present-day wilderness area were the remains of an enormous collapsed volcano that had been active during the

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that has also erupted more-viscous andesite, dacite, and rhyodacite. The smallest and least studied of the three, Middle Sister began eruptive activity 48,000 years ago, and it was primarily built by eruptions occurring between 25,000 and 18,000 years ago. One of the earliest major eruptive

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The Three Sisters join several other volcanoes in the eastern segment of the Cascade Range known as the High Cascades, which trends north–south. Constructed towards the end of the Pleistocene Epoch, these mountains are underlain by more ancient volcanoes that subsided due to parallel north–south

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forests on the eastern slopes. Due to fire suppression over the past century, the forests have become overgrown, and at higher elevations, they are further susceptible to summertime fires, which threaten surrounding life and property. In the 21st century, wildfires have been larger and more

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The Three Sisters form the center of a region of closely grouped volcanic peaks. This is in contrast to the typical 40-to-60 mi (64-to-97 km) spacing between volcanoes elsewhere in the Cascades. Among the most active volcanic areas in the Cascades and one of the most densely populated

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account for about a third of the Three Sisters Wilderness, and this area is known as the Alpine Crest Region. Rising from about 5,200 ft (1,600 m) to 10,358 ft (3,157 m) in elevation, the Alpine Crest Region features the wilderness area's most-frequented glaciers, lakes, and

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South Sister is the easiest of the three to climb, and has a trail all the way to the summit. The standard route up the south ridge runs for 12.6 mi (20.3 km) round trip, rising from 5,446 ft (1,660 m) at the trailhead to 10,363 ft (3,159 m) at its summit. It is a

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from flank vents from the south and southwest flanks, followed by a thick rhyolite lava flow. Next, the Devils Hill eruptive cycle consisted of explosive ash eruptions followed by viscous rhyolitic lava flows. Unlike the previous eruptive period, it was caused by the intrusion of a dike of new

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in the area of uplift; the hundreds of small earthquakes subsided after several days. According to a 2011 study, this swarm may have initiated a significant decrease in the peak uplift rate, which dropped by 80% after 2004. By 2007 the uplift had slowed, though the area was still considered

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Most of the Three Sisters glaciers were described for the first time by Ira A. Williams in 1916. Collier Glacier, between North and Middle Sister, was first studied and mapped by Edwin Hodge. Ruth Hopsen Keen took a forty-year photographic record of Collier Glacier, documenting part of the

912:. The dikes and plug were exposed by centuries of erosion. At one point, the volcano stood more than 11,000 ft (3,400 m) high, but erosion reduced this volume by a quarter to a third. The plug is now exposed and forms North Sister's summits at Prouty Peak and the South Horn. 1150:

3 mi (4.8 km) west of the mountain. The ground began to bulge in late 1997, as magma started to pool about 4 mi (6.4 km) underground. Scientists became concerned that the volcano was awakening, but examination of interferograms, or diagrams of patterns formed by

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In 1862, to connect the Willamette Valley to the ranches of Central Oregon and the gold mines of eastern Oregon and Idaho, Felix and Marion Scott traced a route over Scott Pass. This route was known as the Scott Trail, but was superseded in the early 20th century by the

678:. As a result of the increasing incidence of fires, public officials have factored the role of wildfire into planning, including organizing prescribed fires with scientists to protect habitats at risk while minimizing adverse effects on air quality and environmental health. 1188:

radar observations from 1992 to 2001, and it followed up with campaign GPS and tilt-leveling surveys in August 2004. As of 2009, semi-permanent GPS networks have been deployed every year at the Three Sisters, continually showing that inflation persists at South Sister.

951: m) of ice and is the thickest and largest glacier in the region, descends along the north side of Middle Sister, cutting into the west side of North Sister. Erosion from Pleistocene and Holocene glaciation exposed a plug near the center of Middle Sister. 1608:, which led to the reinstatement of French Pete Creek and its surroundings in the Three Sisters Wilderness Area. The Oregon Wilderness Act of 1984 further expanded the wilderness with the addition of 38,100 acres (154 km) around Erma Bell Lakes. 1028:

Despite its relatively young age, every part of South Sister other than its peak has undergone significant erosion due to Pleistocene and Holocene glaciation. Between 30,000 and 15,000 years ago, South Sister's southern flanks were covered with

415:. Diverse species of flora and fauna inhabit the area, which is subject to frequent snowfall, occasional rain, and extreme temperature variation between seasons. The mountains, particularly South Sister, are popular destinations for climbing and 607:. The Collier Glacier, despite a 4,900 ft (1,500 m) retreat and a 64% loss of its surface area between 1910 and 1994, is generally considered to be the largest glacier of the Three Sisters at 160 acres (0.65 km). 3722:

Dzurisin, D.; Lisowski, M.; Wicks, C. W Jr.; Poland, M. P.; Endo, E. T. (2006). "Geodetic observations and modeling of magmatic inflation at the Three Sisters volcanic center, central Oregon Cascade Range, USA".

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present in the lavas of the younger two mountains is unusual relative to nearby peaks. The Three Sisters form the leading edge of a rhyolitic crustal-melting anomaly, which might be explained by a combination of

1632:. Due to extensive erosion and rockfall, North Sister is the most dangerous climb of the three peaks, and is often informally called the "Beast of the Cascades". One of its peaks, Little Brother, can be safely 4129:

Wicks, C. W. Jr.; Dzurisin, D.; Ingebritsen, S.; Thatcher, W.; Lu, Zhong; Iverson, J. (2002). "Magmatic activity beneath the quiescent Three Sisters volcanic center, central Oregon Cascade Range, USA".

1584:. To maintain its authority over the region, the Forest Service decided to create a 191,108-acre (773 km) primitive area in 1937. The following year, at the instigation of Forest Service employee 547:

The Three Sisters have about 130 snowfields and glaciers ranging in altitude from 6,742 to 10,308 ft (2,055 to 3,142 m) with a cumulative surface area of about 2,500 acres (10 km). The

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that overlays a more ancient shield volcano named Little Brother. North Sister is 5 mi (8 km) wide, and its summit elevation is 10,090 ft (3,075 m). Consisting primarily of

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that has generated similar melting and rhyolitic volcanism nearby for the past 16 million years. Like other Cascade volcanoes, the Three Sisters were fed by magma chambers produced by the

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Dzurisin, D.; Lisowski, M.; Wicks, C. W Jr. (2009). "Continuing inflation at Three Sisters volcanic center, central Oregon Cascade Range, USA, from GPS, leveling, and InSAR observations".

2300: 1049:, or glacial valleys, that made the outer walls of the crater rim significantly steeper. The slopes of South Sister contain small glaciers, including the Lost Creek and Prouty glaciers. 113: 1534:

area was getting overgrazed. Despite regulatory measures, sheep grazing peaked in 1910 before being banned in the 1930s at North and Middle Sister, and in 1940 at South Sister.

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From 1986 to 1987, the USGS surveyed the Three Sisters vicinity with tilt-leveling networks and electro-optical distance meters, but South Sister was not the subject of close

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in 1907. In 1908, the forest was split: the eastern half became the Deschutes National Forest, while the western half merged in 1934 to form the Willamette National Forest.

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and shrubby subalpine meadows. This zone has a large winter snowpack, with low temperatures for much of the year. There are patches of mountain hemlock, subalpine fir, and

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The ecology of the Three Sisters reflect their location in central Oregon's Cascade Range. The westside slopes from 3,000 to 6,500 ft (910 to 2,000 m) lie in the

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than any similar Cascade peak, caused by lava intruding into pre-existing rocks. Many of these dikes were pushed aside by the intrusion of a 980 ft (300 m)-wide

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to the west. They harvested berries, made baskets, hunted, and made obsidian arrowheads and spears. Traces of rock art can be seen at Devils Hill, south of South Sister.

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is now two-and-a-half times larger than the Collier Glacier. According to sources, the Prouty Glacier is sometimes considered to be larger than the Collier glacier.

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was passed, but the area still excluded the French Pete Creek basin. Responding to environmental mobilization throughout the state of Oregon, Congress passed the

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The region was active in the Pleistocene, with eruptions between about 650,000 and about 250,000 years ago from an explosively active complex known as the

4896: 1184:. The agency completed a GPS survey campaign, including planning, documentation, and data processing and archiving, at South Sister in 2001, as well as annual 4576: 2698: 856:

lava flows from North Sister overlay the youngest Tumalo pyroclastic deposits, indicating that North Sister was active more recently than 260,000 years ago.

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South Sister, also known as "Charity", is the tallest volcano of the trio, standing at 10,363 ft (3,159 m). The eruptive products range from

1545:. Cascades Reserve was a strip of land from 20 to 60 mi (30 to 100 km) wide around the main crest of the Cascade Range, stretching from the 1131:, though an eruption of ash with local volcanic rock accumulation and slow lava flows is considered most likely. The Three Sisters area does not have 2269: 1176:

early 2000s. Because of the uplift at South Sister, the USGS planned to increase monitoring of the Three Sisters and their vicinity by installing a

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occurred. A 2002 study inferred that the composition of intruding magma was basaltic or rhyolitic. A map at the Lava Lands Visitor Center of the

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North Sister, also known as "Faith", is the oldest and most highly eroded of the three, with zigzagging rock pinnacles between glaciers. It is a

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Middle Sister can also be scrambled, for a round trip of 16.4 mi (26.4 km) and an elevation gain of 4,757 ft (1,450 m).

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Geologic map of Three Sisters volcanic cluster, Cascade Range, Oregon: U.S. Geological Survey Scientific Investigations Map 3186, pamphlet

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Although they are often grouped together as one unit, the three mountains have their own individual geology and eruptive history. Neither

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about 1,200 ft (370 m) high. During the Holocene, smaller glaciers formed, alternating between advance and retreat, depositing

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last erupted about 2,000 years ago and could erupt in the future, threatening life within the region. After satellite imagery detected

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analysis for the next two decades. The volcano was found to be potentially active in 2000, when satellite imagery showed a deforming

455: 190: 391:. Each over 10,000 feet (3,000 meters) in elevation, they are the third-, fourth- and fifth-highest peaks in Oregon. Located in the 6584: 1862: 1805: 1757: 1206: 1185: 6534: 5460: 1597: 7186: 6995: 6990: 6970: 6920: 6796: 6791: 6773: 6670: 6665: 6509: 6410: 5289: 4270: 3322: 1671: 3954:

Poland, M. P.; Lisowski, M.; Dzurisin, D.; Kramer, R.; McLay, M.; Pauk, B. (2017). "Volcano geodesy in the Cascade arc, USA".

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Thorson, T. D.; Bryce, S. A.; Lammers, D. A.; Woods, A. J.; Omernik, J. M.; Kagan, J.; Pater, D. E.; Comstock, J. A. (2003).

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in 1870. Today, the common trail covers 11 mi (18 km) round-trip, gaining 3,165 ft (965 m) in elevation.

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grow beneath the trees. Douglas-fir is dominant below 3,500 ft (1,100 m), while western hemlock dominates above.

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could run down the sides of the mountain, threatening any life in their paths. Eruptions from South Sister could be either

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Pater, D. E.; Bryce, S. A.; Thorson, T. D.; Kagan, J.; Chappell, C.; Omernik, J. M.; Azevedo, S. H.; Woods, A. J. (1998).

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lie between Middle Sister and South Sister. Finally, around the summit of South Sister, in a clockwise direction, are the

7206: 4279: 2234: 1853: 1666: 1160: 510:. The area includes 260 mi (420 km) of trails and many forests, lakes, waterfalls, and streams, including the 7211: 7156: 6504: 4421: 1585: 3538: 5647: 4786: 3674: 2621: 1928: 1554: 5218: 2501:"The Shevlin Park Tuff, Central Oregon Cascades Range: Magmatic processes recorded in an arc-related ash-flow tuff" 841: 2702: 4943: 4248: 2780: 1858: 1152: 443: 262: 7151: 7100: 6342: 5480: 4236: 1596:

of the French Pete Creek basin, despite protests of local environmental activists. The area became part of the

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in 1825. He describes "a number of high mountains" south of Mount Hood. Ten months later in 1826, the botanist

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south of Bend shows the extent of the uplift, which reaches a maximum of 11 in (28 cm). In 2004, an

710:, each of the three volcanoes formed at different times from several variable magmatic sources. The amount of 7196: 5536: 5238: 3753: 1702: 1348:(ash erupted from Mount Mazama). Stream flow changes little throughout the year due to the region's volcanic 494:

The Three Sisters Wilderness covers an area of 281,190 acres (1,137.9 km), making it the second-largest

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between 7,000 and 9,000 ft (2,100 and 2,700 m) on the mountain. The Lewis and Clark glaciers have

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approached the summits from the west and probably named them individually at that time. Explorers, such as

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The Wilderness Concept and the Three Sisters Wilderness: Deschutes and Willamette National Forests, Oregon

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further north. Around 1866, there were reports that one of the Three Sisters emitted some fire and smoke.

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known as Teardrop Pool, the highest lake in Oregon. Its cone consists of basaltic andesite along with red

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national forests in the U.S. state of Oregon, about 10 miles (16 kilometers) south of the nearest town of

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Rock Mesa is an example of a rhyolite dome near the Three Sisters. South Sister rises in the background.

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basin. In 1957, the Forest Service decided to reclassify the area as a wilderness area and removed the

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fragments of various sizes, while the viscous rhyolite domes extrude onto the surface like toothpaste.

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has erupted in the last 14,000 years, and it is considered unlikely that either will ever erupt again.

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at the Three Sisters occurs at 6,500 ft (2,000 m), where the forest canopy opens and the

584: 489: 465: 400: 392: 231: 4054: 2115: 2062: 1025:, formed between 28,000 and 24,000 years ago, roughly around the same time as the main cone. 6885: 6539: 6494: 6067: 5304: 5198: 5073: 4496: 3993:"Time-dependent changes in volcanic inflation rate near Three Sisters, Oregon, revealed by InSAR" 1895: 1562: 1491: 753: 576: 5003: 7141: 6763: 6698: 6594: 6443: 6274: 6264: 6259: 5969: 5829: 5349: 5344: 5243: 5033: 4736: 4541: 4451: 4431: 4167:

Williams, Howel (1944). Louderback, G. D.; Anderson, C. A.; Camp, C. L.; Chaney, R. W. (eds.).

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Sherrod, D. R.; Taylor, E. M.; Ferns, M. L.; Scott, W. E.; Conrey, R. M.; Smith, G. A. (2004).

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in 1843, used the Three Sisters as a landmark from the east. The area was further explored by

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Location of the Three Sisters relative to other major volcanoes in the Cascade Range of Oregon

6965: 6783: 6778: 6733: 6693: 6415: 6085: 5989: 5795: 5541: 5485: 5430: 5395: 5390: 4911: 4441: 4376: 4256: 2301:"Lightning-sparked wildfires prompt large closure of Three Sisters Wilderness east of Eugene" 1694: 507: 1352:. These slopes support nearly pure stands of ponderosa pine. Understory vegetation includes 1340:

The lower eastern slopes of the Three Sisters below 5,200 ft (1,600 m) lie in the

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glaciers retreated during the 20th century, water filled in the spaces left behind, forming

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Aerial view over the Three Sisters Wilderness, showing Middle Sister (left) and South Sister

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are on the northwestern and northeastern slopes of Middle Sister, respectively, while the

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face, while the Renfrew Glacier sits on the northwestern slope. The large but retreating

775: 720: 671: 635: 531: 461: 396: 388: 275: 227: 4143: 4008: 3967: 3788: 3736: 3698: 3673:. Vol. II. New York: Macmillan Publishing Company. pp. 743–788. Archived from 2516: 7082: 6910: 6683: 6627: 6599: 6324: 5334: 5163: 5113: 5108: 4766: 4646: 4636: 4326: 4155: 4022: 3979: 3710: 2305: 1234: 1124: 1088: 728: 600: 384: 93: 806:; it produces lava flows and is less prone to explosive eruptions than silicic magma. 762:

volcanic centers in the world, the Three Sisters region includes nearby peaks such as

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Portrait of Peter Skene Ogden, Western re-discoverer of the Three Sisters, circa 1854

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national forests, they are about 10 miles (16 kilometers) south of the nearest town,

372: 310: 4159: 1091:. Over the past 70 years, scientists have published several reconnaissance maps and 1001: 719:(movement of Earth's solid silicate mantle layer caused by convection currents) and 7010: 6951: 6743: 6738: 6622: 6430: 6420: 6337: 6019: 5869: 5601: 5455: 5400: 5385: 5228: 5183: 5123: 5043: 4811: 4631: 4626: 4581: 4571: 4511: 4391: 4381: 4371: 4346: 4147: 4012: 3971: 3792: 3740: 3702: 1646: 1538: 1527: 1314: 1288: 1218: 1164: 1120: 898: 837: 826: 380: 4278: 4035: 3142: 1953: 1568: 1021:

and tephra, with exposed black and red inner walls made of scoria. Hodge Crest, a

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is nestled between North Sister and Middle Sister and flows to the northwest. The

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Faculty of the School of Geography, Geology and Environmental Science (2006).

3706: 2547: 2270:"11 new wildfires prompt closure of 266,891 acres in Three Sisters Wilderness" 654:(USGS) identified that Carver Lake on South Sister could flood and breach its 7135: 7078: 6946: 6941: 6915: 6865: 6768: 6657: 6609: 6579: 6529: 6524: 6489: 6468: 6372: 6320: 6305: 6080: 6072: 5974: 5849: 5675: 5556: 5475: 5450: 5425: 5324: 5193: 5103: 5053: 5048: 4891: 4871: 4851: 4761: 4746: 4721: 4701: 4691: 4621: 4586: 4526: 4471: 4461: 4411: 4401: 4366: 4351: 4331: 4301: 3020: 3018: 1541:

decided to create the Cascades Forest Reserve, based on the authority of the

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popular climb during August and September, with up to 400 people each day.

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Conrey, RM; Donnelly-Nolan, J; Taylor, EM; Champion, D; Bullen, T (2001).

7115: 7110: 7105: 7000: 6708: 6569: 6564: 6392: 5999: 5994: 5903: 5834: 5757: 5752: 5688: 5611: 5596: 5465: 5414: 5223: 5173: 5143: 5078: 5018: 4846: 4821: 4796: 4671: 4601: 4566: 4516: 4361: 4316: 4151: 4017: 3992: 3156: 2718: 2716: 2714: 2712: 2470: 2468: 2466: 2395: 1384: 1310: 1258: 1242: 1210: 1209:, where precipitation is abundant. Forests here consist predominantly of 1197: 1181: 1092: 1079: 814: 739: 643: 622:

Carver Lake is dammed by a glacial moraine and could produce a dangerous

540: 4111:

The ecology of the timberline and alpine vegetation of the Three Sisters

3808:(Third ed.). Missoula, Montana: Mountain Press Publishing Company. 2964: 2654: 2652: 2650: 2453: 2451: 1978: 1976: 1974: 6870: 6728: 6718: 6499: 6484: 6284: 6205: 6004: 5726: 5698: 5616: 5576: 5370: 5365: 5314: 5208: 5153: 4901: 4886: 4731: 4716: 4681: 4611: 4591: 4506: 4501: 4481: 4426: 4406: 3181: 3179: 3177: 3175: 3173: 3171: 1633: 1550: 1464: 1448: 1345: 1296: 1246: 1136: 1030: 1022: 979: 885: 833: 818: 799: 724: 686: 675: 612: 519: 416: 364: 346: 323: 280: 5632: 2988: 2728: 2709: 2463: 2020:. U.S. Geological Survey, Cascades Volcano Observatory. Archived from 1929:"Three Sisters loop offers one of Oregon's most scenic backpack trips" 1577:

0.93 mi (1,500 m) retreat of the glacier from 1910 to 1994.

655: 6875: 6347: 5859: 5621: 5319: 5168: 5148: 5138: 4831: 4476: 4296: 3204: 3202: 3200: 3198: 3196: 3194: 2647: 2448: 1971: 1455:

species are many of the predators throughout the Three Sisters area.

1432: 1408: 1357: 1306: 1272: 1238: 1230: 1222: 1180:(GPS) receiver, sampling airborne and ground-based gases, and adding 1168: 1106:

Map of hazards from the Three Sisters showing risk of lava flows and

983: 893: 822: 803: 4928: 3168: 1628:

The Three Sisters are a popular climbing destination for hikers and

786:(basaltic) lavas; only South and Middle Sister have an abundance of 738:

The three mountains were also shaped by the changing climate of the

674:, to the public because of 11 lightning-caused fires, including the 5566: 5526: 5098: 5058: 4841: 4055:"Geologic Map of the Bend 30-×60-Minute Quadrangle, Central Oregon" 4034:

Scott, W. E.; Iverson, R.M.; Schilling, S.P.; Fisher, B.J. (2000).

3824: 2480: 2061:. U.S. Forest Service and the University of Montana. Archived from 1572:

North and Middle Sister, with Collier Glacier between the two peaks

1486:

The first Westerner to discover the Three Sisters was the explorer

1396: 1268: 1132: 1063: 1034: 975: 971: 968: 884:

composition than the other two volcanoes. Its deposits are rich in

791: 711: 662: 3849: 3751: 3191: 2553: 2498: 1309:

occurs at 7,500 feet (2,300 m). The vegetation in this harsh

5663: 4916: 1809: 1761: 1502:. As the Willamette Valley was gradually colonized in the 1840s, 1373: 1292: 1143: 1071: 1059: 1038: 1013:

about 0.25 mi (0.40 km) in diameter that holds a small

988: 787: 350: 30: 3902:(Fourth ed.). Portland, Oregon: Oregon Historical Society. 5667: 4291: 4231: 3806:

Fire Mountains of the West: The Cascade and Mono Lake Volcanoes

3005: 3003: 1472: 1444: 1440: 1436: 1428: 1424: 1420: 1280: 1046: 1018: 992: 959: 889: 864: 853: 795: 368: 342: 235: 46: 4280:

The 126 most prominent summits of the United States of America

2823: 661:

Before settlement of the area at the end of the 19th century,

3887:

Forest Conditions in the Cascade Range Forest Reserve, Oregon

2155:. Portland State University and the Oregon Historical Society 2125:. Portland State University and the Oregon Historical Society 1908: 1116: 1107: 881: 840:

deposits in ground eruptions across the area, similar to the

783: 623: 3953: 3456: 3454: 3452: 3450: 3448: 3446: 3444: 3162: 3082: 3041:"Bulge near South Sister volcano has nearly stopped growing" 3024: 3000: 2747: 2745: 2743: 2599: 2597: 2595: 2535: 1553:. In 1905, administration of the Reserve was moved from the 1005:

Teardrop Pool on South Sister is the highest lake in Oregon.

665:

frequently burned through the local forests, especially the

4033: 3826:

Quaternary Magmatism in the Cascades, Geologic Perspectives

3601: 3231: 3229: 3115: 2970: 2436: 1452: 1392: 1042: 782:

to the south. Most of the surrounding volcanoes consist of

3829:. United States Geological Survey. Professional Paper 1744 3584:"Oregon's beginner-friendly mountain a grueling adventure" 3495: 3493: 3441: 2740: 2592: 2582: 2580: 2578: 2576: 2574: 4169:"Volcanoes of the Three Sisters Region, Oregon Cascades" 4093: 3939:(4th ed.). Dubuque, Iowa: Wm. C. Brown Publishers. 3840: 3767: 3667:

Encyclopedia of American Forest and Conservation History

3410: 3226: 3185: 3070: 3058: 2994: 2976: 2958: 2930: 2928: 2903: 2901: 2862: 2757: 2734: 2722: 2679: 2474: 2457: 2426: 2424: 2422: 2401: 2328:"Fire forces trail closures in Three Sisters Wilderness" 2166: 1982: 1580:

In the 1930s, the Three Sisters were part of a proposed

4052: 3804:

Harris, S. L. (2005). "Chapter 13: The Three Sisters".

3429:

Williams, IA (1916). "Glaciers of the Three Sisters ".

3341: 3305: 3303: 3301: 3299: 3297: 3295: 3268: 3246: 3244: 2852: 2850: 2669: 2667: 2658: 2407: 2373: 2371: 2369: 2088: 2035: 1997: 1995: 1993: 1991: 1752: 1750: 1588:, it was expanded by 55,620 acres (225 km) in the 1052: 3916: 3560: 3490: 3478: 3377: 3365: 3208: 2835: 2787: 2571: 2559: 1800: 1798: 1009:

Unlike its sister peaks, South Sister has an uneroded

4036:"Volcano Hazards in the Three Sisters Region, Oregon" 3466: 3102:"Modern Deformation and Uplift in the Sisters Region" 2925: 2913: 2898: 2886: 2874: 2811: 2799: 2635: 2419: 1321:

near the treeline, as well as wet meadows supporting

4196:

Volcanoes of North America: United States and Canada

3353: 3292: 3280: 3256: 3241: 3214: 2940: 2847: 2664: 2523: 2383: 2366: 2190: 2178: 2076: 1988: 1747: 7217:

Stratovolcanoes with shield volcano characteristics

1795: 1095:studies of the Three Sisters, including a detailed 928:Middle Sister, also known as "Hope", is a basaltic 825:. Cinder cones accumulate from the airfall of many 506:to the north and shares its southern edge with the 4198:. Cambridge, England: Cambridge University Press. 3895: 3889:. Vol. 9–10. U.S. Government Printing Office. 3647:75 Scrambles in Oregon: Best Non-Technical Ascents 3536: 3513:"Story of First Ascent of North Sister is Related" 1070:, Hodge theorized that it had collapsed to form a 4176:Bulletin of the Department of Geological Sciences 2779:. U.S. Forest Service. 2004-03-25. Archived from 2701:. U.S. Forest Service. 2004-03-25. Archived from 1467:since the end of the last glaciation, mainly the 379:in western North America extending from southern 7133: 1808:elevation of 3,073.9 meters was converted using 1760:elevation of 3,062.3 meters was converted using 1115:(25 to 51 millimetres) in the city of Bend, and 941:, which contains 700 million cubic feet (20 555:are north of the North Sister summit, while the 3141:. Smithsonian Institution. 2013. Archived from 2018:"Geology and History Summary for Three Sisters" 1707:National Oceanic and Atmospheric Administration 3990: 3934: 3777:Journal of Volcanology and Geothermal Research 3725:Journal of Volcanology and Geothermal Research 3721: 3684: 3121: 3088: 3047:. Eugene, Oregon. Associated Press. 2013-02-05 3009: 2829: 2541: 2519:. Fall Meeting Supplement, Abstract V32D-0994. 2505:Transactions of the American Geophysical Union 2486: 2442: 2207: 2205: 539:Weather varies greatly in the area due to the 5648: 4944: 4264: 4215:Oregon's Wilderness Areas: The Complete Guide 4079:. Guilford, Connecticut: Globe Pequot Press. 2109: 2107: 2105: 2103: 2047: 1498:reported snow-covered peaks visible from the 1342:Ponderosa Pine/Bitterbrush Woodland ecoregion 3935:Plummer, Charles C.; McGeary, David (1988). 3519:. Guard Publishing Co. 1942-01-04. p. 9 2616: 2614: 2612: 70:North 10,090 ft (3,075.3 m) 54:South 10,363 ft (3,158.5 m) 4244:https://www.youtube.com/watch?v=ulCjWYPQ81A 4128: 4107: 3920:Ecoregions of Western Washington and Oregon 3649:. Seattle, Washington: Mountaineers Books. 3630:. Seattle, Washington: Mountaineers Books. 3625: 3607: 3235: 3076: 3064: 2982: 2691: 2202: 1914: 1207:Western Cascade Montane Highlands ecoregion 842:eruption of Vesuvius that destroyed Pompeii 446:improved monitoring in the immediate area. 5655: 5641: 4951: 4937: 4271: 4257: 4193: 3577: 3575: 3035: 3033: 2769: 2751: 2699:"Oregon Volcanoes – Middle Sister Volcano" 2603: 2100: 1606:Endangered American Wilderness Act of 1978 1201:Mountain hemlock growing on andesitic lava 4212: 4016: 3460: 3135:"Three Sisters: Index of Monthly Reports" 2777:"Oregon Volcanoes – South Sister Volcano" 2609: 2263: 2261: 2172: 813:. This area features andesitic and mafic 460:The Three Sisters are at the boundary of 456:Topographic map of the Three Sisters area 363:are closely spaced volcanic peaks in the 4242:The Sisters from the air.(Minute 4.51) 4166: 3893: 3884: 3822: 3428: 3383: 3371: 2946: 2841: 2793: 2586: 2565: 2143: 2141: 2139: 2041: 1863:United States Department of the Interior 1776: 1774: 1728: 1726: 1615: 1567: 1477: 1196: 1101: 1000: 958: 919: 863: 752: 685: 617: 530: 88:5,588 feet (1,703 m) (South Sister) 5662: 3991:Riddick, S. N.; Schmidt, D. A. (2011). 3870:. Bend, Oregon: Wilderness Associates. 3572: 3030: 2554:Faculty of the School of Geography 2006 2298: 2232: 2012: 2010: 1926: 1598:National Wilderness Preservation System 1463:The Three Sisters area was occupied by 62:Middle 10,052 ft (3,063.7 m) 7134: 6921:John Day Fossil Beds National Monument 4194:Wood, C. A.; Kienle, J., eds. (1992). 3865: 3803: 3539:"Trail-Making in the Oregon Mountains" 3484: 3359: 3347: 3309: 3286: 3274: 3262: 3250: 3220: 2995:Hildreth, Fierstein & Calvert 2012 2959:Fierstein, Hildreth & Calvert 2011 2934: 2919: 2907: 2892: 2880: 2868: 2856: 2817: 2805: 2763: 2735:Hildreth, Fierstein & Calvert 2012 2723:Hildreth, Fierstein & Calvert 2012 2685: 2673: 2641: 2529: 2475:Hildreth, Fierstein & Calvert 2012 2458:Hildreth, Fierstein & Calvert 2012 2430: 2413: 2402:Hildreth, Fierstein & Calvert 2012 2389: 2377: 2267: 2258: 2196: 2184: 2094: 2082: 2001: 1983:Hildreth, Fierstein & Calvert 2012 1672:List of volcanoes in the United States 1277:Cascade Crest montane forest ecoregion 1275:zone begins. These forests lie in the 1155:, revealed that only small amounts of 7202:Volcanoes of Deschutes County, Oregon 7192:Shield volcanoes of the United States 7172:Mountains of Deschutes County, Oregon 6881:Fort Rock-Christmas Lake Valley Basin 5636: 4958: 4932: 4252: 4074: 4062:Geologic Investigations Series I–2683 3663: 3581: 3472: 3416: 2136: 1771: 1723: 1689: 1687: 526: 197: 164: 3997:Geochemistry, Geophysics, Geosystems 3644: 3626:Bishop, E. M.; Allen, J. E. (2004). 3566: 3499: 3104:. U.S. Geological Survey. 2013-11-18 2624:. U.S. Geological Survey. 2013-11-15 2113: 2007: 1880: 1878: 1711:United States Department of Commerce 1644:, according to a story published in 1066:epochs. Naming this ancient volcano 1053:Recent history and potential hazards 16:Three volcanic peaks in Oregon, U.S. 3399:. US Forest Service. 2 October 2015 2622:"Eruption History for North Sister" 2353:"Prescribed Fire in Central Oregon" 2055:"Three Sisters Wilderness: General" 1854:Geographic Names Information System 1667:List of Ultras of the United States 1383:Local fauna includes birds such as 1161:Newberry National Volcanic Monument 987:volcano began to alternate between 13: 1825: 1684: 575:is on its southeastern slope. The 14: 7228: 4224: 3885:Langille, Harold Douglas (1903). 3854:. United States Geological Survey 3537:Victor, Mrs. F. F. (March 1870). 2213:"Central Oregon Fire Environment" 1875: 1555:United States General Land Office 778:to the north, and Broken Top and 210:Three Sisters (the United States) 7177:Mountains of Lane County, Oregon 5219:Marble Mountain-Trout Creek Hill 5002: 4230: 3797:10.1016/j.jvolgeores.2011.06.003 3745:10.1016/j.jvolgeores.2005.07.011 3582:Umess, Zach (3 September 2014). 3530: 3505: 3422: 1458: 915: 642:The local area has a history of 196: 189: 163: 156: 35:The Three Sisters, looking north 29: 3926:(Map). U.S. Geological Survey. 3664:Davis, Richard C., ed. (1983). 3389: 3315: 3127: 3094: 2492: 2345: 2320: 2292: 2226: 1946: 1920: 1859:United States Geological Survey 1624:in the Three Sisters Wilderness 1401:golden-mantled ground squirrels 954: 859: 518:. The Three Sisters and nearby 444:United States Geological Survey 5290:Mount Scott (Clackamas County) 4117:(Thesis). Oregon State College 4103:(Map). U.S. Geological Survey. 4077:Climbing the Cascade Volcanoes 1841: 1819: 1561:. The Reserve was renamed the 1403:, and larger species like the 731:under the western edge of the 1: 7187:North American 3000 m summits 5239:Battle Ground Lake State Park 3617: 2299:Darling, Dylan (2017-08-16). 2233:Richard, Terry (2015-08-30). 1927:Richard, Terry (2010-08-28). 1611: 1135:activity, although there are 924:Middle Sister is cone-shaped. 844:. These deposits spread from 742:epoch, during which multiple 733:North American tectonic plate 559:is on its eastern slope. The 498:in Oregon. Designated by the 483: 265:South Sister and North Sister 213:Show map of the United States 6933:Lava Butte (Basin and Range) 6853:Devils Garden Volcanic Field 6729:Lava Butte (Newberry/Tumalo) 6648:Willamette National Cemetery 6149:Sand Mountain Volcanic Field 5421:Mount Scott (Klamath County) 5295:Willamette National Cemetery 4132:Geophysical Research Letters 3756:. The University of Auckland 1816:elevation of 3,075.3 meters. 1768:elevation of 3,063.7 meters. 1559:United States Forest Service 904:North Sister possesses more 449: 7: 7024:Columbia River Basalt Group 6906:Harney Basin Volcanic Field 6605:Southern Oregon Coast Range 6250:Tom Dick and Harry Mountain 5552:Lava Beds National Monument 2268:Urness, Zach (2017-08-15). 1660: 1405:Columbian black-tailed deer 1217:, with minor components of 1087:to chemical techniques and 729:Juan de Fuca tectonic plate 699:in the surrounding region. 504:Mount Washington Wilderness 10: 7233: 7207:Willamette National Forest 6749:Oregon Badlands Wilderness 6638:Upper and Lower Table Rock 5923:Little Chinquapin Mountain 4213:Wuerthner, George (2003). 3323:"Eruption (Three Sisters)" 3122:Riddick & Schmidt 2011 3089:Riddick & Schmidt 2011 2542:Plummer & McGeary 1988 2487:Plummer & McGeary 1988 2443:Riddick & Schmidt 2011 2334:. Bend, Oregon. 2017-08-15 1549:almost to the border with 1543:Forest Reserve Act of 1891 1192: 832:The Tumalo volcano spread 681: 648:Cascade Lakes Scenic Byway 487: 453: 7212:Stratovolcanoes of Oregon 7157:Deschutes National Forest 7101:Cobb-Eickelberg Seamounts 7077: 7009: 6818: 6656: 6319: 5781:Davis Lake Volcanic Field 5674: 5514: 5471:Mountain Lakes Wilderness 5267: 5011: 5000: 4966: 4827:Mount Cleveland (Montana) 4286: 3976:10.1007/s00445-017-1140-x 3848:; Calvert, A. T. (2012). 3707:10.1007/s00445-009-0296-4 1782:"North Sister Quadrangle" 1734:"North Sister Quadrangle" 1360:at higher elevations and 1178:global positioning system 334: 329: 316: 304: 286: 274: 269: 256: 242: 223: 149: 144: 129:44.103449°N 121.7692058°W 105: 92: 82: 45: 40: 28: 23: 6797:Wildcat Mountain Caldera 5532:Black Butte (California) 4979:Franklin Glacier Complex 4697:Mount Cleveland (Alaska) 4662:Mount Jefferson (Oregon) 4642:Mount Jefferson (Nevada) 4108:Van Vechten, GW (1960). 3894:McArthur, L. A. (1974). 3329:. Seattle Weekly Gazette 3139:Global Volcanism Program 1891:Global Volcanism Program 1703:National Geodetic Survey 1677: 1520:Pacific Railroad Surveys 1376:, and sedges grow along 1333:, tufted hairgrass, and 982:. It is a predominantly 502:in 1964, it borders the 490:Three Sisters Wilderness 393:Three Sisters Wilderness 296:(South, Middle) and one 7111:Devils Elbow State Park 7059:Saddle Mountains Basalt 6886:Four Craters Lava Field 6510:Mount Scott (Clackamas) 5305:Rooster Rock State Park 5074:White Chuck Cinder Cone 4217:. Big Earth Publishing. 4040:Open-File Report 99-437 3956:Bulletin of Volcanology 3898:Oregon Geographic Names 3687:Bulletin of Volcanology 3628:Hiking Oregon's Geology 3608:Bishop & Allen 2004 2123:The Oregon Encyclopedia 1915:Bishop & Allen 2004 1896:Smithsonian Institution 1563:Cascade National Forest 1518:in 1855 as part of the 750:eroded the mountains. 371:. They are part of the 134:44.103449; -121.7692058 99:US most prominent peaks 6976:Squaw Ridge Lava Field 6966:Powder River Volcanics 6962:Powder River Volcanics 6595:Siletz River Volcanics 6469:Little Butte Volcanics 6275:Tumalo Volcanic Center 5937:Lost Lake Cinder Cones 5350:Tumalo Volcanic Center 5244:Beacon Rock State Park 5034:Schriebers Meadow Cone 4237:Three Sisters (Oregon) 2752:Wood & Kienle 1992 2604:Wood & Kienle 1992 1625: 1602:Wilderness Act of 1964 1573: 1508:Nathaniel Jarvis Wyeth 1483: 1202: 1139:west of South Sister. 1111: 1006: 964: 925: 869: 811:Tumalo volcanic center 802:. Mafic magma is less 758: 691: 652:U.S. Geological Survey 627: 536: 500:United States Congress 7152:Volcanic crater lakes 6784:Smith Rock State Park 6694:Crooked River Caldera 6671:Bald Mountain Caldera 6034:Mount Scott (Klamath) 5919:Little Cache Mountain 5542:Medicine Lake Volcano 4377:San Gorgonio Mountain 3823:Hildreth, W. (2007). 2489:, pp. 51 and 57. 2355:. U.S. Forest Service 2309:. Guard Publishing Co 2215:. U.S. Forest Service 1619: 1571: 1481: 1391:, small mammals like 1364:at lower elevations. 1200: 1110:in the immediate area 1105: 1004: 962: 923: 867: 756: 689: 621: 534: 508:Waldo Lake Wilderness 353:travel on some routes 101:, 85th (South Sister) 7197:Subduction volcanoes 6991:Strawberry Volcanics 6540:Oregon's Matterhorns 6094:Pine Marten Mountain 6068:Oregon's Matterhorns 5134:Goat Island Mountain 4974:Silverthrone Caldera 4862:Abercrombie Mountain 4687:Great Sitkin Volcano 4239:at Wikimedia Commons 4152:10.1029/2001GL014205 4097:Ecoregions of Oregon 4018:10.1029/2011GC003826 3645:Bond, B. I. (2005). 2245:Advance Publications 2149:"Glaciers in Oregon" 2116:"Glaciers of Oregon" 2114:Fountain, Andrew G. 1954:"The Oregon Top 100" 1516:John Strong Newberry 1492:Hudson's Bay Company 1362:antelope bitterbrush 1172:potentially active. 704:Cascade Volcanic Arc 636:moraine-dammed lakes 373:Cascade Volcanic Arc 311:Cascade Volcanic Arc 7182:Mountains of Oregon 7167:Landmarks in Oregon 7096:Brown Bear Seamount 7044:Hat Rock State Park 7029:Grande Ronde Basalt 6986:Strawberry Mountain 6699:Deschutes Formation 6301:Williamson Mountain 6217:Three Fingered Jack 6186:South Pinhead Butte 6056:North Pinhead Butte 5772:Cupit Mary Mountain 5740:Chinquapin Mountain 4984:Mount Meager massif 4467:White Mountain Peak 4144:2002GeoRL..29.1122W 4009:2011GGG....1212005R 3968:2017BVol...79...59P 3866:Joslin, L. (2005). 3789:2011JVGR..207..145F 3737:2006JVGR..150...35D 3699:2009BVol...71.1091D 3419:, pp. 743–788. 3186:Thorson et al. 2003 3010:Dzurisin et al 2006 2830:Dzurisin et al 2009 2659:Sherrod et al. 2004 2517:2001AGUFM.V32D0994C 2153:Oregon Encyclopedia 1917:, pp. 139–142. 1638:George Lemuel Woods 1622:Pacific Crest Trail 1537:In 1892, President 1417:American black bear 1354:greenleaf manzanita 1099:published in 2012. 776:Three Fingered Jack 672:Pacific Crest Trail 395:at the boundary of 389:Northern California 375:, a segment of the 125: / 7083:Juan de Fuca Ridge 6911:Hole-in-the-Ground 6788:Tea Table Mountain 6628:Tualatin Mountains 6325:Oregon Coast Range 6294:West Pinhead Butte 5927:Little Nash Crater 5904:Little Aspen Butte 5164:Old Snowy Mountain 5114:Burroughs Mountain 5109:Little Tahoma Peak 4727:Sierra Blanca Peak 4637:Sovereign Mountain 4347:Shishaldin Volcano 4327:Mount Marcus Baker 4075:Smoot, J. (1993). 3517:The Register-Guard 3327:Volcanoes USGS Gov 3163:Poland et al. 2017 3045:The Register-Guard 3025:Poland et al. 2017 2961:, pp. 147–48. 2871:, pp. 187–88. 2766:, pp. 186–87. 2688:, pp. 182–84. 2306:The Register-Guard 2059:Wilderness Connect 1935:. Advance Internet 1626: 1620:Two hikers on the 1574: 1528:McKenzie Pass Road 1484: 1331:black alpine sedge 1235:Pacific silver fir 1203: 1112: 1089:radiometric dating 1078:collapsed to form 1007: 965: 926: 897:years ago, in the 888:and red and black 870: 759: 692: 628: 537: 527:Physical geography 180:Show map of Oregon 177:Location in Oregon 73: NAVD 88 65: NAVD 88 57: NAVD 88 41:Highest point 7162:Dormant volcanoes 7147:Cascade Volcanoes 7129: 7128: 6937:Mahogany Mountain 6714:Gearhart Mountain 6473:Little Pilot Rock 6383:Crescent Mountain 6358:Boring Lava Field 6169:Sheridan Mountain 5835:Greylock Mountain 5630: 5629: 5501:Gearhart Mountain 5340:Crescent Mountain 5275:Boring Lava Field 5204:Sawtooth Mountain 4960:Cascade Volcanoes 4926: 4925: 4777:Flat Top Mountain 4752:North Schell Peak 4547:Mount San Antonio 4322:Mount Saint Elias 4307:Mount Fairweather 4235:Media related to 4205:978-0-521-43811-7 4086:978-1-56044-889-1 3946:978-0-697-05092-2 3909:978-0-87595-102-7 3877:978-0-9647167-4-2 3815:978-0-87842-511-2 3693:(10): 1091–1110. 3656:978-0-89886-550-9 3637:978-0-89886-847-0 3588:Statesman Journal 3569:, pp. 61–64. 3502:, pp. 59–61. 3350:, pp. 65–66. 3277:, pp. 49–50. 3209:Pater et al. 1998 2971:Scott et al. 2000 2511:(47): V32D–0994. 2416:, pp. 30–31. 2404:, pp. 11–12. 2275:Statesman Journal 2097:, pp. 32–33. 1594:old-growth forest 1590:French Pete Creek 1582:National Monument 1500:Willamette Valley 1488:Peter Skene Ogden 1301:Newberry knotweed 1167:occurred with an 1153:wave interference 1121:pyroclastic flows 878:basaltic andesite 468:counties and the 403:counties and the 357: 356: 75: 67: 59: 7224: 7011:Columbia Plateau 6952:Mutton Mountains 6792:Wildcat Mountain 6744:Ochoco Mountains 6739:Newberry Volcano 6724:Grizzly Mountain 6658:Eastern Cascades 6368:Chamberlain Hill 6321:Western Cascades 6077:Peavine Mountain 6044:Mount Washington 6020:Mount McLoughlin 5966:Maklaks Mountain 5947:Lookout Mountain 5870:Howlock Mountain 5823:Frog Lake Buttes 5744:Clear Lake Butte 5657: 5650: 5643: 5634: 5633: 5602:Bumpass Mountain 5537:Rainbow Mountain 5456:Mount McLoughlin 5401:Howlock Mountain 5386:Newberry Volcano 5229:Trout Creek Hill 5184:Mount St. Helens 5124:Cowlitz Chimneys 5044:Hannegan caldera 5006: 4967:British Columbia 4953: 4946: 4939: 4930: 4929: 4812:Mount Timpanogos 4807:Carlisle Volcano 4632:Makushin Volcano 4582:Mount Washington 4572:Pogromni Volcano 4512:Mount Chiginagak 4392:Mount Veniaminof 4372:San Jacinto Peak 4273: 4266: 4259: 4250: 4249: 4234: 4218: 4209: 4190: 4188: 4187: 4173: 4163: 4138:(7): 26:1–26:4. 4125: 4123: 4122: 4116: 4104: 4102: 4090: 4071: 4069: 4068: 4059: 4049: 4047: 4046: 4030: 4020: 3987: 3950: 3937:Physical Geology 3931: 3925: 3913: 3901: 3890: 3881: 3862: 3860: 3859: 3837: 3835: 3834: 3819: 3800: 3783:(3–4): 145–179. 3764: 3762: 3761: 3748: 3718: 3681: 3679: 3672: 3660: 3641: 3611: 3605: 3599: 3598: 3596: 3594: 3579: 3570: 3564: 3558: 3557: 3555: 3554: 3543:Overland Monthly 3534: 3528: 3527: 3525: 3524: 3509: 3503: 3497: 3488: 3482: 3476: 3470: 3464: 3458: 3439: 3438: 3426: 3420: 3414: 3408: 3407: 3405: 3404: 3393: 3387: 3381: 3375: 3369: 3363: 3357: 3351: 3345: 3339: 3338: 3336: 3334: 3319: 3313: 3307: 3290: 3284: 3278: 3272: 3266: 3260: 3254: 3248: 3239: 3236:Van Vechten 1960 3233: 3224: 3218: 3212: 3206: 3189: 3183: 3166: 3160: 3154: 3153: 3151: 3150: 3131: 3125: 3119: 3113: 3112: 3110: 3109: 3098: 3092: 3086: 3080: 3077:Wicks et al 2002 3074: 3068: 3065:Wicks et al 2002 3062: 3056: 3055: 3053: 3052: 3037: 3028: 3022: 3013: 3007: 2998: 2992: 2986: 2983:Wicks et al 2002 2980: 2974: 2968: 2962: 2956: 2950: 2944: 2938: 2932: 2923: 2917: 2911: 2905: 2896: 2890: 2884: 2878: 2872: 2866: 2860: 2854: 2845: 2839: 2833: 2827: 2821: 2815: 2809: 2803: 2797: 2791: 2785: 2784: 2773: 2767: 2761: 2755: 2749: 2738: 2732: 2726: 2720: 2707: 2706: 2695: 2689: 2683: 2677: 2671: 2662: 2656: 2645: 2639: 2633: 2632: 2630: 2629: 2618: 2607: 2601: 2590: 2584: 2569: 2563: 2557: 2551: 2545: 2539: 2533: 2527: 2521: 2520: 2496: 2490: 2484: 2478: 2472: 2461: 2455: 2446: 2440: 2434: 2428: 2417: 2411: 2405: 2399: 2393: 2387: 2381: 2375: 2364: 2363: 2361: 2360: 2349: 2343: 2342: 2340: 2339: 2324: 2318: 2317: 2315: 2314: 2296: 2290: 2289: 2287: 2286: 2265: 2256: 2255: 2253: 2251: 2230: 2224: 2223: 2221: 2220: 2209: 2200: 2194: 2188: 2182: 2176: 2170: 2164: 2163: 2161: 2160: 2145: 2134: 2133: 2131: 2130: 2120: 2111: 2098: 2092: 2086: 2080: 2074: 2073: 2071: 2070: 2051: 2045: 2039: 2033: 2032: 2030: 2029: 2014: 2005: 1999: 1986: 1980: 1969: 1968: 1966: 1965: 1950: 1944: 1943: 1941: 1940: 1924: 1918: 1912: 1906: 1905: 1903: 1902: 1882: 1873: 1872: 1870: 1869: 1845: 1839: 1838: 1836: 1835: 1823: 1817: 1802: 1793: 1792: 1790: 1789: 1778: 1769: 1754: 1745: 1744: 1742: 1741: 1730: 1721: 1720: 1718: 1717: 1691: 1647:Overland Monthly 1539:Grover Cleveland 1471:to the east and 1289:tufted hairgrass 1219:mountain hemlock 1165:earthquake swarm 1082:. In the 1940s, 947: 946: 940: 899:Late Pleistocene 880:, it has a more 827:pyroclastic rock 768:Mount Washington 585:Skinner Glaciers 553:Villard Glaciers 441: 433: 429: 425: 381:British Columbia 338: 246: 214: 200: 199: 193: 181: 167: 166: 160: 140: 139: 137: 136: 135: 130: 126: 123: 122: 121: 118: 71: 63: 55: 33: 21: 20: 7232: 7231: 7227: 7226: 7225: 7223: 7222: 7221: 7132: 7131: 7130: 7125: 7073: 7054:Pendleton Vents 7049:Hermiston Butte 7005: 6981:Steens Mountain 6959:Poker Jim Ridge 6956:Pillars of Rome 6861:Diamond Craters 6857:Dooley Mountain 6820:Basin and Range 6814: 6810:Yamsay Mountain 6652: 6585:Saddle Mountain 6550:Pepper Mountain 6481:Lost Lake Butte 6459:Laurel Mountain 6440:Indian Mountain 6421:Harter Mountain 6406:Elk Rock Island 6315: 6311:Zigzag Mountain 6270:Tumalo Mountain 6025:Mount Multnomah 6010:Mount Jefferson 5890:Le Conte Crater 5758:Crater Mountain 5670: 5661: 5631: 5626: 5607:Dittmar Volcano 5572:Burney Mountain 5547:Schonchin Butte 5510: 5496:Yamsay Mountain 5376:Tumalo Mountain 5360:Mount Multnomah 5330:Mount Jefferson 5285:Elk Rock Island 5263: 5234:Tumtum Mountain 5039:Kulshan caldera 5007: 4998: 4994:Mount Garibaldi 4962: 4957: 4927: 4922: 4921: 4907:Korovin Volcano 4877:Chiricahua Peak 4772:Veniaminof Peak 4652:Isanotski Peaks 4437:Mount Tom White 4412:Iliamna Volcano 4382:Charleston Peak 4352:Redoubt Volcano 4312:Mount Blackburn 4282: 4277: 4227: 4222: 4221: 4206: 4185: 4183: 4171: 4120: 4118: 4114: 4100: 4087: 4066: 4064: 4057: 4044: 4042: 3947: 3928:to back of map) 3923: 3910: 3878: 3857: 3855: 3832: 3830: 3816: 3759: 3757: 3677: 3670: 3657: 3638: 3620: 3615: 3614: 3606: 3602: 3592: 3590: 3580: 3573: 3565: 3561: 3552: 3550: 3535: 3531: 3522: 3520: 3511: 3510: 3506: 3498: 3491: 3483: 3479: 3471: 3467: 3459: 3442: 3427: 3423: 3415: 3411: 3402: 3400: 3395: 3394: 3390: 3382: 3378: 3370: 3366: 3358: 3354: 3346: 3342: 3332: 3330: 3321: 3320: 3316: 3308: 3293: 3285: 3281: 3273: 3269: 3261: 3257: 3249: 3242: 3234: 3227: 3219: 3215: 3207: 3192: 3184: 3169: 3161: 3157: 3148: 3146: 3133: 3132: 3128: 3120: 3116: 3107: 3105: 3100: 3099: 3095: 3087: 3083: 3075: 3071: 3063: 3059: 3050: 3048: 3039: 3038: 3031: 3023: 3016: 3008: 3001: 2993: 2989: 2981: 2977: 2969: 2965: 2957: 2953: 2945: 2941: 2933: 2926: 2918: 2914: 2906: 2899: 2891: 2887: 2879: 2875: 2867: 2863: 2855: 2848: 2840: 2836: 2832:, p. 1091. 2828: 2824: 2816: 2812: 2804: 2800: 2792: 2788: 2775: 2774: 2770: 2762: 2758: 2750: 2741: 2733: 2729: 2721: 2710: 2697: 2696: 2692: 2684: 2680: 2672: 2665: 2657: 2648: 2640: 2636: 2627: 2625: 2620: 2619: 2610: 2602: 2593: 2585: 2572: 2564: 2560: 2552: 2548: 2540: 2536: 2528: 2524: 2497: 2493: 2485: 2481: 2473: 2464: 2456: 2449: 2441: 2437: 2429: 2420: 2412: 2408: 2400: 2396: 2388: 2384: 2376: 2367: 2358: 2356: 2351: 2350: 2346: 2337: 2335: 2326: 2325: 2321: 2312: 2310: 2297: 2293: 2284: 2282: 2280:Gannett Company 2266: 2259: 2249: 2247: 2231: 2227: 2218: 2216: 2211: 2210: 2203: 2195: 2191: 2183: 2179: 2171: 2167: 2158: 2156: 2147: 2146: 2137: 2128: 2126: 2118: 2112: 2101: 2093: 2089: 2081: 2077: 2068: 2066: 2053: 2052: 2048: 2040: 2036: 2027: 2025: 2016: 2015: 2008: 2000: 1989: 1981: 1972: 1963: 1961: 1952: 1951: 1947: 1938: 1936: 1925: 1921: 1913: 1909: 1900: 1898: 1886:"Three Sisters" 1884: 1883: 1876: 1867: 1865: 1847: 1846: 1842: 1833: 1831: 1828:"OREGON P2000s" 1824: 1820: 1803: 1796: 1787: 1785: 1780: 1779: 1772: 1755: 1748: 1739: 1737: 1732: 1731: 1724: 1715: 1713: 1693: 1692: 1685: 1680: 1663: 1614: 1469:Northern Paiute 1461: 1215:western hemlock 1195: 1148:tectonic uplift 1068:Mount Multnomah 1055: 957: 944: 942: 939:Collier Glacier 938: 918: 862: 848:to the town of 748:glacial advance 744:glacial periods 684: 640:contiguous U.S. 605:Eugene Glaciers 569:Hayden Glaciers 561:Collier Glacier 529: 496:wilderness area 492: 486: 458: 452: 439: 436:tectonic uplift 431: 427: 423: 336: 294:stratovolcanoes 244: 219: 218: 217: 216: 215: 212: 211: 208: 207: 206: 205: 201: 184: 183: 182: 179: 178: 175: 174: 173: 172: 168: 133: 131: 127: 124: 119: 116: 114: 112: 111: 78: 36: 17: 12: 11: 5: 7230: 7220: 7219: 7214: 7209: 7204: 7199: 7194: 7189: 7184: 7179: 7174: 7169: 7164: 7159: 7154: 7149: 7144: 7127: 7126: 7124: 7123: 7118: 7113: 7108: 7103: 7098: 7093: 7091:Axial Seamount 7087: 7085: 7075: 7074: 7072: 7071: 7069:Wanapum Basalt 7066: 7061: 7056: 7051: 7046: 7041: 7036: 7031: 7026: 7021: 7015: 7013: 7007: 7006: 7004: 7003: 6998: 6996:Tower Mountain 6993: 6988: 6983: 6978: 6973: 6968: 6963: 6960: 6957: 6954: 6949: 6944: 6939: 6934: 6931: 6928: 6926:Jordan Craters 6923: 6918: 6913: 6908: 6903: 6898: 6896:Hager Mountain 6893: 6888: 6883: 6878: 6873: 6868: 6863: 6858: 6855: 6850: 6845: 6842: 6839: 6834: 6828: 6826: 6824:Eastern Oregon 6816: 6815: 6813: 6812: 6807: 6804: 6799: 6794: 6789: 6786: 6781: 6776: 6771: 6766: 6761: 6756: 6751: 6746: 6741: 6736: 6731: 6726: 6721: 6716: 6711: 6706: 6704:Hager Mountain 6701: 6696: 6691: 6686: 6681: 6678: 6673: 6668: 6662: 6660: 6654: 6653: 6651: 6650: 6645: 6640: 6635: 6630: 6625: 6623:Three Pyramids 6620: 6615: 6612: 6607: 6602: 6597: 6592: 6587: 6582: 6577: 6572: 6567: 6562: 6557: 6552: 6547: 6542: 6537: 6535:Olson Mountain 6532: 6527: 6522: 6517: 6515:Mount Sylvania 6512: 6507: 6502: 6497: 6495:Mount Defiance 6492: 6487: 6482: 6479: 6474: 6471: 6466: 6461: 6456: 6454:Larch Mountain 6451: 6446: 6441: 6438: 6436:Hunsinger Peak 6433: 6428: 6426:Highland Butte 6423: 6418: 6413: 6411:Grass Mountain 6408: 6403: 6398: 6395: 6390: 6385: 6380: 6375: 6370: 6365: 6360: 6355: 6350: 6345: 6340: 6335: 6329: 6327: 6317: 6316: 6314: 6313: 6308: 6303: 6298: 6297:Whiteface Peak 6295: 6292: 6290:Waldo Mountain 6287: 6282: 6277: 6272: 6267: 6262: 6257: 6252: 6247: 6242: 6240:Three Trappers 6237: 6219: 6214: 6211: 6208: 6203: 6200: 6195: 6190: 6187: 6184: 6179: 6176: 6171: 6166: 6161: 6156: 6151: 6146: 6141: 6136: 6134:Royce Mountain 6131: 6126: 6123: 6122:Robinson Butte 6120: 6115: 6110: 6105: 6102: 6099: 6096: 6091: 6090:Pinhead Buttes 6088: 6083: 6078: 6075: 6070: 6065: 6060: 6057: 6054: 6049: 6046: 6041: 6039:Mount Thielsen 6036: 6031: 6028: 6022: 6017: 6012: 6007: 6002: 6000:Mount Harriman 5997: 5992: 5987: 5985:Mount Bachelor 5982: 5977: 5972: 5967: 5964: 5962:Maklaks Crater 5959: 5954: 5949: 5944: 5939: 5934: 5929: 5924: 5921: 5916: 5914:Little Brother 5911: 5909:Little Belknap 5906: 5901: 5896: 5891: 5888: 5885: 5880: 5875: 5874:Irish Mountain 5872: 5867: 5862: 5857: 5852: 5847: 5842: 5837: 5832: 5827: 5824: 5821: 5818: 5816:Forgotten Cone 5813: 5808: 5803: 5798: 5793: 5788: 5786:Davis Mountain 5783: 5778: 5773: 5770: 5765: 5760: 5755: 5750: 5745: 5742: 5737: 5735:Cache Mountain 5732: 5731:Buckskin Butte 5729: 5724: 5719: 5714: 5712:Belknap Crater 5709: 5704: 5701: 5696: 5691: 5686: 5684:Applegate Peak 5680: 5678: 5672: 5671: 5660: 5659: 5652: 5645: 5637: 5628: 5627: 5625: 5624: 5619: 5614: 5609: 5604: 5599: 5594: 5589: 5584: 5579: 5574: 5569: 5564: 5559: 5554: 5549: 5544: 5539: 5534: 5529: 5524: 5518: 5516: 5512: 5511: 5509: 5508: 5503: 5498: 5493: 5488: 5483: 5478: 5473: 5468: 5463: 5461:Brown Mountain 5458: 5453: 5448: 5443: 5441:Applegate Peak 5438: 5433: 5428: 5423: 5418: 5408: 5406:Mount Thielsen 5403: 5398: 5393: 5388: 5383: 5381:Mount Bachelor 5378: 5373: 5368: 5363: 5357: 5352: 5347: 5342: 5337: 5332: 5327: 5322: 5317: 5312: 5310:Larch Mountain 5307: 5302: 5297: 5292: 5287: 5282: 5280:Mount Sylvania 5277: 5271: 5269: 5265: 5264: 5262: 5261: 5256: 5254:Greenleaf Peak 5251: 5249:Table Mountain 5246: 5241: 5236: 5231: 5226: 5221: 5216: 5211: 5206: 5201: 5196: 5191: 5186: 5181: 5176: 5171: 5166: 5161: 5156: 5151: 5146: 5141: 5136: 5131: 5126: 5121: 5116: 5111: 5106: 5101: 5096: 5094:Cathedral Rock 5091: 5086: 5081: 5076: 5071: 5066: 5061: 5056: 5051: 5046: 5041: 5036: 5031: 5026: 5024:Sherman Crater 5021: 5015: 5013: 5009: 5008: 5001: 4999: 4997: 4996: 4991: 4986: 4981: 4976: 4970: 4968: 4964: 4963: 4956: 4955: 4948: 4941: 4933: 4924: 4923: 4920: 4919: 4914: 4909: 4904: 4899: 4894: 4889: 4884: 4879: 4874: 4869: 4864: 4859: 4854: 4849: 4844: 4839: 4834: 4829: 4824: 4819: 4814: 4809: 4804: 4799: 4794: 4789: 4784: 4779: 4774: 4769: 4764: 4759: 4754: 4749: 4744: 4739: 4734: 4729: 4724: 4719: 4714: 4709: 4707:Mount Wrangell 4704: 4699: 4694: 4689: 4684: 4679: 4674: 4669: 4664: 4659: 4654: 4649: 4644: 4639: 4634: 4629: 4627:Tanaga Volcano 4624: 4619: 4617:Mount Natazhat 4614: 4609: 4607:Humphreys Peak 4604: 4599: 4597:Mount Mitchell 4594: 4589: 4584: 4579: 4574: 4569: 4564: 4562:Telescope Peak 4559: 4554: 4552:Kichatna Spire 4549: 4544: 4539: 4534: 4529: 4524: 4522:Sacajawea Peak 4519: 4514: 4509: 4504: 4499: 4497:Mount Hesperus 4494: 4492:Mount Vsevidof 4489: 4484: 4479: 4474: 4469: 4464: 4459: 4454: 4449: 4444: 4439: 4434: 4429: 4424: 4419: 4414: 4409: 4404: 4399: 4394: 4389: 4387:Pavlof Volcano 4384: 4379: 4374: 4369: 4364: 4359: 4354: 4349: 4344: 4339: 4334: 4329: 4324: 4319: 4314: 4309: 4304: 4299: 4294: 4288: 4287: 4284: 4283: 4276: 4275: 4268: 4261: 4253: 4247: 4246: 4240: 4226: 4225:External links 4223: 4220: 4219: 4210: 4204: 4191: 4164: 4126: 4105: 4091: 4085: 4072: 4050: 4031: 3988: 3951: 3945: 3932: 3914: 3908: 3891: 3882: 3876: 3863: 3838: 3820: 3814: 3801: 3765: 3749: 3731:(1–3): 35–54. 3719: 3682: 3680:on 2012-10-28. 3661: 3655: 3642: 3636: 3622: 3621: 3619: 3616: 3613: 3612: 3610:, p. 139. 3600: 3571: 3559: 3529: 3504: 3489: 3487:, p. 185. 3477: 3475:, p. 137. 3465: 3463:, p. 175. 3461:Wuerthner 2003 3440: 3421: 3409: 3388: 3376: 3364: 3352: 3340: 3314: 3291: 3279: 3267: 3255: 3240: 3225: 3213: 3190: 3167: 3155: 3126: 3114: 3093: 3081: 3069: 3057: 3029: 3014: 2999: 2987: 2975: 2963: 2951: 2939: 2937:, p. 182. 2924: 2922:, p. 193. 2912: 2910:, p. 192. 2897: 2895:, p. 191. 2885: 2883:, p. 188. 2873: 2861: 2846: 2834: 2822: 2820:, p. 190. 2810: 2808:, p. 189. 2798: 2786: 2783:on 2011-05-12. 2768: 2756: 2754:, p. 185. 2739: 2727: 2708: 2705:on 2011-05-16. 2690: 2678: 2663: 2646: 2644:, p. 183. 2634: 2608: 2606:, p. 184. 2591: 2570: 2558: 2546: 2534: 2522: 2491: 2479: 2462: 2447: 2435: 2433:, p. 179. 2418: 2406: 2394: 2382: 2365: 2344: 2319: 2291: 2257: 2240:OregonLive.com 2225: 2201: 2189: 2177: 2175:, p. 174. 2173:Wuerthner 2003 2165: 2135: 2099: 2087: 2075: 2046: 2044:, p. 544. 2034: 2006: 1987: 1970: 1960:. June 8, 2013 1945: 1933:OregonLive.com 1919: 1907: 1874: 1849:"South Sister" 1840: 1826:Martin, Andy. 1818: 1794: 1770: 1746: 1722: 1699:NGS Data Sheet 1695:"South Sister" 1682: 1681: 1679: 1676: 1675: 1674: 1669: 1662: 1659: 1613: 1610: 1547:Columbia River 1504:Euro-Americans 1460: 1457: 1451:, and several 1370:stream dogwood 1366:Mountain alder 1323:Brewer's sedge 1319:whitebark pine 1297:red paintbrush 1194: 1191: 1097:geological map 1084:Howel Williams 1054: 1051: 956: 953: 917: 914: 874:shield volcano 861: 858: 823:rhyolite domes 790:rocks such as 780:Mount Bachelor 764:Belknap Crater 683: 680: 667:ponderosa pine 632:Little Ice Age 573:Diller Glacier 557:Thayer Glacier 528: 525: 488:Main article: 485: 482: 451: 448: 387:and Oregon to 355: 354: 340: 332: 331: 327: 326: 320: 314: 313: 308: 302: 301: 298:shield volcano 290: 284: 283: 278: 272: 271: 267: 266: 260: 254: 253: 248: 240: 239: 225: 221: 220: 209: 203: 202: 195: 194: 188: 187: 186: 185: 176: 170: 169: 162: 161: 155: 154: 153: 152: 151: 150: 147: 146: 142: 141: 109: 103: 102: 96: 90: 89: 86: 80: 79: 77: 76: 68: 60: 51: 49: 43: 42: 38: 37: 34: 26: 25: 15: 9: 6: 4: 3: 2: 7229: 7218: 7215: 7213: 7210: 7208: 7205: 7203: 7200: 7198: 7195: 7193: 7190: 7188: 7185: 7183: 7180: 7178: 7175: 7173: 7170: 7168: 7165: 7163: 7160: 7158: 7155: 7153: 7150: 7148: 7145: 7143: 7142:Cascade Range 7140: 7139: 7137: 7122: 7119: 7117: 7114: 7112: 7109: 7107: 7104: 7102: 7099: 7097: 7094: 7092: 7089: 7088: 7086: 7084: 7080: 7079:Pacific Coast 7076: 7070: 7067: 7065: 7064:Steens Basalt 7062: 7060: 7057: 7055: 7052: 7050: 7047: 7045: 7042: 7040: 7039:Imnaha Basalt 7037: 7035: 7032: 7030: 7027: 7025: 7022: 7020: 7017: 7016: 7014: 7012: 7008: 7002: 6999: 6997: 6994: 6992: 6989: 6987: 6984: 6982: 6979: 6977: 6974: 6972: 6969: 6967: 6964: 6961: 6958: 6955: 6953: 6950: 6948: 6947:Modoc Plateau 6945: 6943: 6942:Malheur Butte 6940: 6938: 6935: 6932: 6930:Lambert Rocks 6929: 6927: 6924: 6922: 6919: 6917: 6916:Jackies Butte 6914: 6912: 6909: 6907: 6904: 6902: 6899: 6897: 6894: 6892: 6889: 6887: 6884: 6882: 6879: 6877: 6874: 6872: 6869: 6867: 6866:Doherty Slide 6864: 6862: 6859: 6856: 6854: 6851: 6849: 6846: 6843: 6840: 6838: 6835: 6833: 6830: 6829: 6827: 6825: 6821: 6817: 6811: 6808: 6805: 6803: 6800: 6798: 6795: 6793: 6790: 6787: 6785: 6782: 6780: 6777: 6775: 6772: 6770: 6769:Powell Buttes 6767: 6765: 6764:Pine Mountain 6762: 6760: 6757: 6755: 6752: 6750: 6747: 6745: 6742: 6740: 6737: 6735: 6732: 6730: 6727: 6725: 6722: 6720: 6717: 6715: 6712: 6710: 6707: 6705: 6702: 6700: 6697: 6695: 6692: 6690: 6687: 6685: 6682: 6679: 6677: 6674: 6672: 6669: 6667: 6666:Bald Mountain 6664: 6663: 6661: 6659: 6655: 6649: 6646: 6644: 6641: 6639: 6636: 6634: 6631: 6629: 6626: 6624: 6621: 6619: 6616: 6614:Sunshine Rock 6613: 6611: 6610:Spencer Butte 6608: 6606: 6603: 6601: 6598: 6596: 6593: 6591: 6588: 6586: 6583: 6581: 6580:Roxy Ann Peak 6578: 6576: 6575:Ross Mountain 6573: 6571: 6568: 6566: 6563: 6561: 6558: 6556: 6553: 6551: 6548: 6546: 6543: 6541: 6538: 6536: 6533: 6531: 6530:Nesmith Point 6528: 6526: 6525:Mount Talbert 6523: 6521: 6518: 6516: 6513: 6511: 6508: 6506: 6503: 6501: 6498: 6496: 6493: 6491: 6490:Mount Ashland 6488: 6486: 6483: 6480: 6478: 6477:Lookout Point 6475: 6472: 6470: 6467: 6465: 6464:Lenhart Butte 6462: 6460: 6457: 6455: 6452: 6450: 6447: 6445: 6444:Iron Mountain 6442: 6439: 6437: 6434: 6432: 6429: 6427: 6424: 6422: 6419: 6417: 6414: 6412: 6409: 6407: 6404: 6402: 6399: 6397:French's Dome 6396: 6394: 6391: 6389: 6386: 6384: 6381: 6379: 6376: 6374: 6373:Clatsop Butte 6371: 6369: 6366: 6364: 6361: 6359: 6356: 6354: 6353:Bone Mountain 6351: 6349: 6346: 6344: 6341: 6339: 6336: 6334: 6331: 6330: 6328: 6326: 6322: 6318: 6312: 6309: 6307: 6306:Wizard Island 6304: 6302: 6299: 6296: 6293: 6291: 6288: 6286: 6283: 6281: 6278: 6276: 6273: 6271: 6268: 6266: 6265:Triangle Peak 6263: 6261: 6260:Triangle Hill 6258: 6256: 6253: 6251: 6248: 6246: 6245:Timber Crater 6243: 6241: 6238: 6235: 6231: 6230:Middle Sister 6227: 6223: 6222:Three Sisters 6220: 6218: 6215: 6212: 6209: 6207: 6204: 6201: 6199: 6198:Teardrop Pool 6196: 6194: 6193:Talapus Butte 6191: 6188: 6185: 6183: 6182:South Belknap 6180: 6177: 6175: 6172: 6170: 6167: 6165: 6162: 6160: 6159:Sentinel Rock 6157: 6155: 6152: 6150: 6147: 6145: 6144:Sand Mountain 6142: 6140: 6137: 6135: 6132: 6130: 6127: 6124: 6121: 6119: 6116: 6114: 6111: 6109: 6106: 6103: 6100: 6098:Pothole Butte 6097: 6095: 6092: 6089: 6087: 6084: 6082: 6081:Pelican Butte 6079: 6076: 6074: 6073:Olallie Butte 6071: 6069: 6066: 6064: 6061: 6058: 6055: 6053: 6050: 6047: 6045: 6042: 6040: 6037: 6035: 6032: 6029: 6027:(unconfirmed) 6026: 6023: 6021: 6018: 6016: 6013: 6011: 6008: 6006: 6003: 6001: 5998: 5996: 5995:Mount Carmine 5993: 5991: 5988: 5986: 5983: 5981: 5980:Merriam Point 5978: 5976: 5973: 5971: 5968: 5965: 5963: 5960: 5958: 5955: 5953: 5950: 5948: 5945: 5943: 5942:Lookout Butte 5940: 5938: 5935: 5933: 5930: 5928: 5925: 5922: 5920: 5917: 5915: 5912: 5910: 5907: 5905: 5902: 5900: 5897: 5895: 5892: 5889: 5886: 5884: 5881: 5879: 5876: 5873: 5871: 5868: 5866: 5863: 5861: 5858: 5856: 5853: 5851: 5850:Hayrick Butte 5848: 5846: 5843: 5841: 5838: 5836: 5833: 5831: 5830:Garfield Peak 5828: 5826:Fuji Mountain 5825: 5822: 5819: 5817: 5814: 5812: 5809: 5807: 5804: 5802: 5799: 5797: 5794: 5792: 5789: 5787: 5784: 5782: 5779: 5777: 5774: 5771: 5769: 5766: 5764: 5761: 5759: 5756: 5754: 5751: 5749: 5746: 5743: 5741: 5738: 5736: 5733: 5730: 5728: 5725: 5723: 5720: 5718: 5715: 5713: 5710: 5708: 5705: 5702: 5700: 5697: 5695: 5692: 5690: 5687: 5685: 5682: 5681: 5679: 5677: 5676:High Cascades 5673: 5669: 5665: 5658: 5653: 5651: 5646: 5644: 5639: 5638: 5635: 5623: 5620: 5618: 5615: 5613: 5610: 5608: 5605: 5603: 5600: 5598: 5595: 5593: 5590: 5588: 5585: 5583: 5582:Snow Mountain 5580: 5578: 5575: 5573: 5570: 5568: 5565: 5563: 5560: 5558: 5557:Modoc Plateau 5555: 5553: 5550: 5548: 5545: 5543: 5540: 5538: 5535: 5533: 5530: 5528: 5525: 5523: 5520: 5519: 5517: 5513: 5507: 5504: 5502: 5499: 5497: 5494: 5492: 5489: 5487: 5484: 5482: 5479: 5477: 5476:Roxy Ann Peak 5474: 5472: 5469: 5467: 5464: 5462: 5459: 5457: 5454: 5452: 5451:Pelican Butte 5449: 5447: 5444: 5442: 5439: 5437: 5434: 5432: 5429: 5427: 5426:Wizard Island 5424: 5422: 5419: 5416: 5412: 5409: 5407: 5404: 5402: 5399: 5397: 5394: 5392: 5389: 5387: 5384: 5382: 5379: 5377: 5374: 5372: 5369: 5367: 5364: 5362:(unvalidated) 5361: 5358: 5356: 5355:Three Sisters 5353: 5351: 5348: 5346: 5345:Iron Mountain 5343: 5341: 5338: 5336: 5333: 5331: 5328: 5326: 5325:Olallie Butte 5323: 5321: 5318: 5316: 5313: 5311: 5308: 5306: 5303: 5301: 5298: 5296: 5293: 5291: 5288: 5286: 5283: 5281: 5278: 5276: 5273: 5272: 5270: 5266: 5260: 5259:Wind Mountain 5257: 5255: 5252: 5250: 5247: 5245: 5242: 5240: 5237: 5235: 5232: 5230: 5227: 5225: 5222: 5220: 5217: 5215: 5212: 5210: 5207: 5205: 5202: 5200: 5197: 5195: 5194:Indian Heaven 5192: 5190: 5187: 5185: 5182: 5180: 5177: 5175: 5172: 5170: 5167: 5165: 5162: 5160: 5157: 5155: 5152: 5150: 5147: 5145: 5142: 5140: 5137: 5135: 5132: 5130: 5127: 5125: 5122: 5120: 5117: 5115: 5112: 5110: 5107: 5105: 5104:Mount Rainier 5102: 5100: 5097: 5095: 5092: 5090: 5087: 5085: 5082: 5080: 5077: 5075: 5072: 5070: 5067: 5065: 5062: 5060: 5057: 5055: 5054:Ruth Mountain 5052: 5050: 5049:Hannegan Peak 5047: 5045: 5042: 5040: 5037: 5035: 5032: 5030: 5027: 5025: 5022: 5020: 5017: 5016: 5014: 5010: 5005: 4995: 4992: 4990: 4987: 4985: 4982: 4980: 4977: 4975: 4972: 4971: 4969: 4965: 4961: 4954: 4949: 4947: 4942: 4940: 4935: 4934: 4931: 4918: 4915: 4913: 4910: 4908: 4905: 4903: 4900: 4898: 4895: 4893: 4892:Mount Augusta 4890: 4888: 4885: 4883: 4880: 4878: 4875: 4873: 4872:Mount Gareloi 4870: 4868: 4865: 4863: 4860: 4858: 4855: 4853: 4852:Mount Deborah 4850: 4848: 4845: 4843: 4840: 4838: 4835: 4833: 4830: 4828: 4825: 4823: 4820: 4818: 4815: 4813: 4810: 4808: 4805: 4803: 4800: 4798: 4795: 4793: 4790: 4788: 4787:Mount Steller 4785: 4783: 4782:Bearhole Peak 4780: 4778: 4775: 4773: 4770: 4768: 4765: 4763: 4762:Mount Foresta 4760: 4758: 4755: 4753: 4750: 4748: 4747:Snowshoe Peak 4745: 4743: 4740: 4738: 4737:Mount Russell 4735: 4733: 4730: 4728: 4725: 4723: 4722:Mount Seattle 4720: 4718: 4715: 4713: 4710: 4708: 4705: 4703: 4702:McDonald Peak 4700: 4698: 4695: 4693: 4690: 4688: 4685: 4683: 4680: 4678: 4675: 4673: 4670: 4668: 4665: 4663: 4660: 4658: 4655: 4653: 4650: 4648: 4645: 4643: 4640: 4638: 4635: 4633: 4630: 4628: 4625: 4623: 4622:Hanagita Peak 4620: 4618: 4615: 4613: 4610: 4608: 4605: 4603: 4600: 4598: 4595: 4593: 4590: 4588: 4587:Mount Igikpak 4585: 4583: 4580: 4578: 4575: 4573: 4570: 4568: 4565: 4563: 4560: 4558: 4555: 4553: 4550: 4548: 4545: 4543: 4542:Mount Douglas 4540: 4538: 4535: 4533: 4530: 4528: 4527:Mount Neacola 4525: 4523: 4520: 4518: 4515: 4513: 4510: 4508: 4505: 4503: 4500: 4498: 4495: 4493: 4490: 4488: 4485: 4483: 4480: 4478: 4475: 4473: 4472:Mount Crillon 4470: 4468: 4465: 4463: 4462:Mount Foraker 4460: 4458: 4455: 4453: 4452:Mount Kimball 4450: 4448: 4445: 4443: 4440: 4438: 4435: 4433: 4432:Mount Sanford 4430: 4428: 4425: 4423: 4420: 4418: 4417:Mount Olympus 4415: 4413: 4410: 4408: 4405: 4403: 4402:Mount Hubbard 4400: 4398: 4395: 4393: 4390: 4388: 4385: 4383: 4380: 4378: 4375: 4373: 4370: 4368: 4367:Mount Torbert 4365: 4363: 4360: 4358: 4355: 4353: 4350: 4348: 4345: 4343: 4340: 4338: 4335: 4333: 4332:Mount Whitney 4330: 4328: 4325: 4323: 4320: 4318: 4315: 4313: 4310: 4308: 4305: 4303: 4302:Mount Rainier 4300: 4298: 4295: 4293: 4290: 4289: 4285: 4281: 4274: 4269: 4267: 4262: 4260: 4255: 4254: 4251: 4245: 4241: 4238: 4233: 4229: 4228: 4216: 4211: 4207: 4201: 4197: 4192: 4181: 4177: 4170: 4165: 4161: 4157: 4153: 4149: 4145: 4141: 4137: 4133: 4127: 4113: 4112: 4106: 4099: 4098: 4092: 4088: 4082: 4078: 4073: 4063: 4056: 4051: 4041: 4037: 4032: 4028: 4024: 4019: 4014: 4010: 4006: 4002: 3998: 3994: 3989: 3985: 3981: 3977: 3973: 3969: 3965: 3961: 3957: 3952: 3948: 3942: 3938: 3933: 3929: 3922: 3921: 3915: 3911: 3905: 3900: 3899: 3892: 3888: 3883: 3879: 3873: 3869: 3864: 3853: 3852: 3847: 3846:Fierstein, J. 3843: 3839: 3828: 3827: 3821: 3817: 3811: 3807: 3802: 3798: 3794: 3790: 3786: 3782: 3778: 3774: 3770: 3769:Fierstein, J. 3766: 3755: 3750: 3746: 3742: 3738: 3734: 3730: 3726: 3720: 3716: 3712: 3708: 3704: 3700: 3696: 3692: 3688: 3683: 3676: 3669: 3668: 3662: 3658: 3652: 3648: 3643: 3639: 3633: 3629: 3624: 3623: 3609: 3604: 3589: 3585: 3578: 3576: 3568: 3563: 3548: 3544: 3540: 3533: 3518: 3514: 3508: 3501: 3496: 3494: 3486: 3481: 3474: 3469: 3462: 3457: 3455: 3453: 3451: 3449: 3447: 3445: 3436: 3432: 3425: 3418: 3413: 3398: 3397:"Our History" 3392: 3386:, p. 18. 3385: 3384:Langille 1903 3380: 3374:, p. 15. 3373: 3372:Langille 1903 3368: 3362:, p. 67. 3361: 3356: 3349: 3344: 3328: 3324: 3318: 3312:, p. 62. 3311: 3306: 3304: 3302: 3300: 3298: 3296: 3289:, p. 61. 3288: 3283: 3276: 3271: 3265:, p. 49. 3264: 3259: 3253:, p. 48. 3252: 3247: 3245: 3237: 3232: 3230: 3223:, p. 60. 3222: 3217: 3210: 3205: 3203: 3201: 3199: 3197: 3195: 3187: 3182: 3180: 3178: 3176: 3174: 3172: 3164: 3159: 3145:on 2014-08-15 3144: 3140: 3136: 3130: 3123: 3118: 3103: 3097: 3091:, p. 11. 3090: 3085: 3078: 3073: 3066: 3061: 3046: 3042: 3036: 3034: 3027:, p. 11. 3026: 3021: 3019: 3012:, p. 38. 3011: 3006: 3004: 2997:, p. 15. 2996: 2991: 2984: 2979: 2972: 2967: 2960: 2955: 2948: 2947:Williams 1944 2943: 2936: 2931: 2929: 2921: 2916: 2909: 2904: 2902: 2894: 2889: 2882: 2877: 2870: 2865: 2859:, p. 37. 2858: 2853: 2851: 2844:, p. 30. 2843: 2842:Hildreth 2007 2838: 2831: 2826: 2819: 2814: 2807: 2802: 2796:, p. 49. 2795: 2794:Williams 1944 2790: 2782: 2778: 2772: 2765: 2760: 2753: 2748: 2746: 2744: 2737:, p. 12. 2736: 2731: 2725:, p. 11. 2724: 2719: 2717: 2715: 2713: 2704: 2700: 2694: 2687: 2682: 2676:, p. 35. 2675: 2670: 2668: 2661:, p. 11. 2660: 2655: 2653: 2651: 2643: 2638: 2623: 2617: 2615: 2613: 2605: 2600: 2598: 2596: 2589:, p. 28. 2588: 2587:Hildreth 2007 2583: 2581: 2579: 2577: 2575: 2568:, p. 27. 2567: 2566:Hildreth 2007 2562: 2555: 2550: 2544:, p. 54. 2543: 2538: 2532:, p. 33. 2531: 2526: 2518: 2514: 2510: 2506: 2502: 2495: 2488: 2483: 2477:, p. 10. 2476: 2471: 2469: 2467: 2459: 2454: 2452: 2444: 2439: 2432: 2427: 2425: 2423: 2415: 2410: 2403: 2398: 2392:, p. 31. 2391: 2386: 2380:, p. 30. 2379: 2374: 2372: 2370: 2354: 2348: 2333: 2329: 2323: 2308: 2307: 2302: 2295: 2281: 2277: 2276: 2271: 2264: 2262: 2246: 2242: 2241: 2236: 2229: 2214: 2208: 2206: 2199:, p. 47. 2198: 2193: 2187:, p. 44. 2186: 2181: 2174: 2169: 2154: 2150: 2144: 2142: 2140: 2124: 2117: 2110: 2108: 2106: 2104: 2096: 2091: 2085:, p. 34. 2084: 2079: 2065:on 2014-04-01 2064: 2060: 2056: 2050: 2043: 2042:McArthur 1974 2038: 2024:on 2013-10-02 2023: 2019: 2013: 2011: 2004:, p. 57. 2003: 1998: 1996: 1994: 1992: 1984: 1979: 1977: 1975: 1959: 1955: 1949: 1934: 1930: 1923: 1916: 1911: 1897: 1893: 1892: 1887: 1881: 1879: 1864: 1860: 1856: 1855: 1850: 1844: 1829: 1822: 1815: 1811: 1807: 1801: 1799: 1783: 1777: 1775: 1767: 1763: 1759: 1753: 1751: 1735: 1729: 1727: 1712: 1708: 1704: 1700: 1696: 1690: 1688: 1683: 1673: 1670: 1668: 1665: 1664: 1658: 1654: 1651: 1649: 1648: 1643: 1642:James McBride 1639: 1635: 1631: 1623: 1618: 1609: 1607: 1603: 1599: 1595: 1591: 1587: 1583: 1578: 1570: 1566: 1564: 1560: 1556: 1552: 1548: 1544: 1540: 1535: 1531: 1529: 1523: 1521: 1517: 1513: 1509: 1505: 1501: 1497: 1496:David Douglas 1493: 1489: 1480: 1476: 1474: 1470: 1466: 1459:Human history 1456: 1454: 1450: 1446: 1442: 1438: 1434: 1430: 1426: 1422: 1418: 1414: 1413:Roosevelt elk 1410: 1406: 1402: 1398: 1394: 1390: 1389:ruffed grouse 1386: 1381: 1379: 1375: 1371: 1367: 1363: 1359: 1355: 1351: 1347: 1343: 1338: 1336: 1332: 1328: 1324: 1320: 1316: 1312: 1308: 1304: 1302: 1298: 1294: 1290: 1286: 1285:dwarf willows 1282: 1278: 1274: 1270: 1266: 1264: 1260: 1256: 1252: 1248: 1244: 1240: 1236: 1232: 1228: 1227:subalpine fir 1224: 1220: 1216: 1212: 1208: 1199: 1190: 1187: 1183: 1179: 1173: 1170: 1166: 1162: 1158: 1154: 1149: 1145: 1140: 1138: 1134: 1130: 1126: 1122: 1118: 1109: 1104: 1100: 1098: 1094: 1090: 1085: 1081: 1077: 1073: 1069: 1065: 1061: 1050: 1048: 1044: 1040: 1036: 1032: 1026: 1024: 1020: 1016: 1012: 1011:summit crater 1003: 999: 997: 994: 990: 985: 981: 977: 973: 970: 961: 952: 950: 934: 931: 930:stratovolcano 922: 916:Middle Sister 913: 911: 910:volcanic plug 907: 902: 900: 895: 891: 887: 883: 879: 875: 866: 857: 855: 851: 847: 843: 839: 835: 830: 828: 824: 821:, as well as 820: 816: 812: 807: 805: 801: 797: 793: 789: 785: 781: 777: 773: 769: 765: 755: 751: 749: 746:occurred and 745: 741: 736: 734: 730: 726: 722: 721:decompression 718: 713: 709: 708:Cascade Range 705: 700: 698: 688: 679: 677: 673: 668: 664: 659: 657: 653: 649: 645: 641: 637: 633: 625: 620: 616: 614: 610: 609:Eliot Glacier 606: 602: 598: 594: 590: 586: 582: 578: 574: 570: 566: 562: 558: 554: 550: 545: 542: 533: 524: 521: 517: 516:Whychus Creek 513: 509: 505: 501: 497: 491: 481: 479: 475: 471: 467: 463: 457: 447: 445: 442:in 2000, the 437: 428:Middle Sister 420: 418: 414: 410: 406: 402: 398: 394: 390: 386: 382: 378: 377:Cascade Range 374: 370: 366: 362: 361:Three Sisters 352: 348: 344: 341: 339: 337:Easiest route 333: 328: 325: 321: 319: 318:Last eruption 315: 312: 309: 307: 303: 299: 295: 291: 289: 288:Mountain type 285: 282: 279: 277: 273: 268: 264: 261: 259: 255: 252: 251:Cascade Range 249: 247: 241: 237: 233: 229: 226: 222: 204:Three Sisters 192: 171:Three Sisters 159: 148: 143: 138: 110: 108: 104: 100: 97: 95: 91: 87: 85: 81: 74: 69: 66: 61: 58: 53: 52: 50: 48: 44: 39: 32: 27: 24:Three Sisters 22: 19: 7121:Yaquina Head 7106:Devils Elbow 6971:Saddle Butte 6901:Harney Basin 6891:Glass Buttes 6844:Clarks Butte 6806:Yainax Ridge 6802:Yainax Butte 6754:Paulina Peak 6689:Cline Buttes 6680:Bly Mountain 6676:Barnes Butte 6560:Powell Butte 6505:Mount Pisgah 6431:High Prairie 6416:Grizzly Peak 6388:Devil's Rest 6378:Cook's Butte 6363:Cascade Head 6280:Twin Craters 6255:Tot Mountain 6234:South Sister 6233: 6229: 6226:North Sister 6225: 6221: 6206:The Pinnacle 6197: 6189:Summit Butte 6139:Rustler Peak 6128: 6086:Phantom Ship 6059:North Wilson 6048:Mount Wilson 6015:Mount Mazama 5990:Mount Bailey 5975:Merriam Cone 5970:Melvin Butte 5952:Lumrum Butte 5913: 5887:Lemiti Butte 5878:Katsuk Butte 5865:Hoodoo Butte 5855:Hillman Peak 5845:Hamner Butte 5806:Dutton Cliff 5796:Diamond Peak 5768:Cryder Butte 5722:Black Crater 5703:Barlow Butte 5592:Mount Tehama 5587:Latour Butte 5562:Brushy Butte 5522:Mount Shasta 5506:Yainax Butte 5486:Grizzly Peak 5446:Rustler Peak 5436:Hillman Peak 5431:Phantom Ship 5411:Mount Mazama 5396:Mount Bailey 5391:Diamond Peak 5354: 5214:Big Lava Bed 5179:Spiral Butte 5159:Gilbert Peak 5129:Old Desolate 5119:Banshee Peak 5089:Mount Daniel 5084:Mount Hinman 5069:Glacier Peak 5064:Mount Terror 5029:Black Buttes 4989:Mount Cayley 4867:Mount Lemmon 4817:Bashful Peak 4802:Mount Miller 4792:Mount Stuart 4757:Hayford Peak 4712:South Sister 4711: 4667:Isthmus Peak 4657:Deseret Peak 4557:De Long Peak 4537:Mount Graham 4487:Gannett Peak 4457:Mount Griggs 4447:Glacier Peak 4442:Wheeler Peak 4357:Mount Elbert 4342:Mount Shasta 4214: 4195: 4184:. 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Peaklist 1788:2017-11-25 1740:2017-11-25 1716:2017-06-29 1612:Recreation 1551:California 1433:wolverines 1346:Mazama Ash 1315:herbaceous 1269:Timberline 1023:false peak 980:rhyodacite 894:lava flows 886:palagonite 819:Lava Butte 800:rhyodacite 725:subduction 676:Milli Fire 613:Mount Hood 601:Lost Creek 520:Broken Top 484:Wilderness 470:Willamette 454:See also: 417:scrambling 405:Willamette 385:Washington 365:U.S. state 347:scrambling 281:Quaternary 234:counties, 117:44°06′12″N 84:Prominence 7019:Boat Rock 6876:Fort Rock 6684:China Hat 6600:Snow Peak 6401:Elk Point 6348:Battle Ax 6210:The Twins 6129:Rock Mesa 6030:Mount Ray 5899:Llao Rock 5860:Hogg Rock 5811:Egan Cone 5801:Dry Butte 5748:Cleetwood 5664:Volcanoes 5622:Goosenest 5335:Snow Peak 5320:Battle Ax 5169:Ives Peak 5149:Mount Aix 5139:Mount Wow 4832:Kawaikini 4767:Star Peak 4477:Mauna Loa 4337:Haleakalā 4297:Mauna Kea 4027:134308941 3984:133965157 3715:128434879 3567:Bond 2005 3500:Bond 2005 1634:scrambled 1600:when the 1409:mule deer 1397:chipmunks 1358:snowberry 1307:Tree line 1273:subalpine 1239:red alder 1231:grand fir 1223:noble fir 1169:epicenter 1125:explosive 1062:or early 984:rhyolitic 663:wildfires 523:meadows. 474:Deschutes 466:Deschutes 450:Geography 409:Deschutes 401:Deschutes 232:Deschutes 145:Geography 47:Elevation 7034:Hat Rock 6832:Big Hole 6213:The Wife 6108:Red Cone 6101:Redcloud 5894:Llao Bay 5567:Big Cave 5527:Shastina 5099:Mount Si 5059:Icy Peak 4842:Arc Dome 4160:16234883 3593:17 April 1661:See also 1144:geodetic 1133:fumarole 1129:effusive 1117:mudflows 1074:just as 1064:Pliocene 1039:moraines 1035:headwall 976:rhyolite 972:andesite 969:basaltic 854:Basaltic 817:such as 792:andesite 712:rhyolite 706:and the 697:faulting 383:through 330:Climbing 258:Topo map 224:Location 6633:TV Hill 6104:Red Box 4917:Kamakou 4140:Bibcode 4005:Bibcode 3964:Bibcode 3785:Bibcode 3733:Bibcode 3695:Bibcode 3333:30 July 2513:Bibcode 1814:NAVD 88 1812:to the 1810:VERTCON 1806:NGVD 29 1766:NAVD 88 1764:to the 1762:VERTCON 1758:NGVD 29 1557:to the 1490:of the 1445:weasels 1441:badgers 1437:martens 1429:coyotes 1425:cougars 1421:Bobcats 1378:streams 1374:willows 1193:Ecology 1072:caldera 1060:Miocene 1047:cirques 989:dacitic 890:cinders 838:plinian 804:viscous 788:silicic 727:of the 682:Geology 565:Renfrew 478:Sisters 413:Sisters 351:glacier 349:, plus 300:(North) 270:Geology 94:Listing 7081:& 6822:& 6323:& 5668:Oregon 5268:Oregon 4292:Denali 4202: 4158: 4083: 4025: 3982: 3943: 3906: 3874: 3812: 3713: 3653: 3634: 3431:Mazama 1784:. USGS 1736:. 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