Sister Oregon
CVO Website - Three Sisters Volcanoes, Oregon
The ages of most volcanoes in the Three Sisters area are not preciselyknown. North Sister , a basaltic andesite pyroclastic and lava cone that rests on a shield volcano , is the oldest of the Three Sisters and postdates the approximately 0.3-million-year-old Shevlin Park Tuff . Middle Sister is intermediate in age between North and South Sister and, like South Sister, is compositionally diverse. Broken Top volcano is also younger than Shevlin Park Tuff and is older than South Sister, but its age relation toMiddle and North Sister is not known. The relative degree oferosion of Broken Top is a complex complex composite cone of dominantlybasaltic andesite that intermittently erupted andesite, dacite, and rhyolite aslava flows, pyroclastic flows, and pyroclastic falls. Cayuse Crater , which is located between Broken Topand the Cascades Lakes Highway, and two nearby vents on the southwest flank ofBroken Top erupted during the earliest Holocene orlates Pleistocene time, but these ... [Read More]
Beaverton Sister Cities Foundation - Cluses, France
Our most recent sister city agreement was signed with Cluses located in the southeastern section of France near Mt. Blanc in the French Alps. It enjoys year-round recreation activities, such as hiking, mountain climbing, swimming, boating, parasailing, golfing, skiing and ice-skating. Similarities include its history, with farmers establishing a city that is now involved with manufacturing precision parts for electronic, automobile and medical industries. Cluses lies in the L'Arve Valley on the L'Arve River. On the river is a museum housing an old water wheel used for power generation. This building is close to an ancient bridge that is said to have been ordered repaired by Napoleon. A Mayor, nine Deputy Mayors and 29 City Councilors govern the City. Cluses has a population of 18,000. ... [Read More]
Beaverton Sister Cities Foundation
The responsibilities of being a Board member include: regular attendance of Board meetings, participation in the various Board sub-committees, promotion of the Foundation in the community, fundraising assistance, as well as participation in trips to our Sister Cities and hosting assistance for visitors from those cities. ... Sister Cities, City of Beaverton ... [Read More]
CVO Website - Scott and Gardner, 1990,Field Trip Guide to the Central Oregon High Cascades
Map [21K,InlineGIF] -- Geologic setting of the Three-Sisters-Mount Bachelor area ... This field excursion to the central Oregon High Cascades highlightsaspects of Quaternary volcanic and glacial history in the vicinity of Mount Bachelor (formerly Bachelor Butte) and South Sister.Part 2 (Bend Area) portion of the field excursion to the central Oregon HighCascades highlights aspects of the ash-flow tuffs in the Bend area. The guidecontains brief descriptions of the stops, and some of the key features andinterpretations of the stops are discussed further in the paper by Hill andTaylor at the end of the guide. ... [Read More]
CVO Menu - Mount Bachelor Vicinity, Oregon
The Three Sisters area contains 5 large cones of Quaternary age -North Sister, Middle Sister, South Sister, Broken Top, and Mount Bachelor. ...Mount Bachelor, which is between 11,000 and 15,000 years old is the youngest of these volcanoes in the Cascades. ... "Climb (?) Mount Bachelor", "The Summit", and "View from the Top" information from:Scott, Gardner, Sarna-Wojcicki, (eds.), 1989,Guidebook for Field Trip to the Mount Bachelor-South Sister-Bend Area, Central Oregon High Cascades:USGS Open-File Report 89-645; andScott and Gardner, 1990, Field Trip Guide to the Central Oregon High Cascades:Oregon Geology, v.52, n.5 and n.6 ... [Read More]
Volcano Hazards in the Three Sisters Region, Oregon
Three Sisters is one of three potentially active volcanic centers that lie close to rapidly growing communities and resort areas in Central Oregon. Two types of volcanoes exist in the Three Sisters region and each poses distinct hazards to people and property. South Sister, Middle Sister, and Broken Top, major composite volcanoes clustered near the center of the region, have erupted repeatedly over tens of thousands of years and may erupt explosively in the future. In contrast, mafic volcanoes, which range from small cinder cones to large shield volcanoes like North Sister and Belknap Crater, are typically short-lived (weeks to centuries) and erupt less explosively than do composite volcanoes. Hundreds of mafic volcanoes scattered through the Three Sisters region are part of a much longer zone along the High Cascades of Oregon in which birth of new mafic volcanoes is possible. This report describes the types of hazardous events that can occur in the Three Sisters region and the accomp ... [Read More]
CVO Menu - Three Sister Vicinity, Oregon
The Three Sisters area contains 5 large cones of Quaternary age--North Sister, Middle Sister, South Sister, Broken Top, and Mount Bachelor. North Sister and Broken Top are deeply dissected and probably have been inactive for at least 100,000 years. Middle Sister is younger than North Sister, and was active in late Pleistocene but not postglacial time. South Sister is the least dissected; its basaltic andesite summit cone has a well preserved crater. Most of South Sister predates late Wisconsin glaciation and is therefore older than 25,000 years; however, eruptions of rhyolite from flank vents have occurred as recently as 2000 years ago. ... [Read More]
CVO Website - Central Oregon High Cascades
South Sister volcano is chiefly andesite with minor dacite and rhyodacite. Broken Top (east of South Sister) is basaltic andesite withminor interbedded dacite and rhyodacite lavas and small-volume ash-flow tuffs. Middle Sister (north of South Sister) is basalt with minor basalticandesite, andesite, dacite, and rhyodacite. South Sister and nearby volcanoesare relatively late products of long-continued, compositionally diverse, andlocalized silicic magmatism. ... ... The central Oregon Cascade Range peaks that presently sustain glaciers or permanent ice massesare, from north to south, Mount Jefferson , Three Fingered Jack , North Sister, Middle Sister, South Sister , and Broken Top . In addition, Mount Bachelor , Diamond Peak , and Mount Thielsen all had small glaciers that persisted until the end of the Little Ice Age in the early 20thcentury. The Three Sisters Wilderness Area is the most extensively glacierized region of thecentral Oregon Cascade Range, with 17 named glaciers that presently cover about 7.5 squarekilometers. ... ... [Read More]
CVO Menu - Three Sisters, Oregon
-- includes Broken Top ...Cayuse Crater ...Collier Glacier ...Eruptive History ..."Faith", "Hope", and "Charity" ...High Cascades ...Le Conte Crater ...Middle Sister ...North Sister ...Rock Mesa ...Shevlin Park Tuff ... South Sister ...Three Sisters ...Volcanic Background ...Volcano Monitoring ... ... CVO Photo Archives - Three Sisters ... Publications and Reports - Three Sisters ... [Read More]
Beaverton Sister Cities Foundation
The Beaverton Sister Cities Foundation, a non-profit corporation, was established in 1986 to encourage cultural, educational, and economic relationships with cities from around the world. Particular attention was given initially to Pacific Rim countries, due to the strong existing cultural and economic ties with Beaverton. The first sister city relationships were established within Japan, Taiwan, and South Korea. A Russian city, located near the Pacific Rim, was the next relationship developed. Beaverton has since turned to the European continent, signing with a German city in 1993 and a French city in 1999. ... [Read More]
|