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Hannegan Caldera
Hannegan caldera is a 3.72 million year old volcanic collapse structure in the North Cascades of the U.S. state of Washington (state), Washington. The caldera collapsed during two separate volcanic eruptions that produced as much as 140 km3 of rhyolite ash. The caldera is filled with 55-60 km3 of tuff consisting of ignimbrite, wall-rock breccia, and post-caldera sedimentary rocks. Rocks filling the caldera are lumped into a stratigraphic unit called the Hannegan volcanics. This geologic unit is subdivided into the ignimbrite of Hannegan Peak, which is overlain by the slightly younger ignimbrite of Ruth Mountain. Hannegan caldera is centered 8.9 km northeast of Mount Shuksan. Prominent geographic points within the caldera include Hannegan Peak, Hannegan Pass, Ruth Mountain, Icy Peak, the western portion of Copper Ridge and the uppermost reaches of the Chilliwack River. The caldera’s western margin is in Mount Baker-Snoqualmie National Forest but most of the structure is in North ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hannegan Peak
Hannegan Peak is a mountain summit located in the Skagit Range, which is a subset of the North Cascades in Whatcom County of Washington state. It is situated immediately north of Hannegan Pass, and north of Ruth Mountain in the Mount Baker Wilderness, which is managed by Mount Baker-Snoqualmie National Forest. Banning Austin and R.M. Lyle made the first ascent of Hannegan Peak in 1893 while surveying for a possible road across the Cascades over Hannegan Pass to Whatcom Pass. This peak was named in association with Hannegan Pass, which in turn was named for Tom Hannegan, State Road Commissioner at that time. Although no road was built, a four-mile trail leads hikers to the pass, and another one-mile path leads to the summit. Peaks which can be seen from the summit include Mount Shuksan, Ruth Mountain, Mineral Mountain, Mount Baker, Mount Sefrit, Mount Larrabee, Granite Mountain, Mount Chardonnay, Mount Rexford, the Picket Range, and many more. Climate Hannegan Peak is lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
