Jack Mountain is the 17th highest mountain in Washington state.[3] It is one of the 10 non-volcanic peaks in Washington State over 9,000 feet (2,700 m). It towers dramatically over the south end of Ross Lake, rising 7,450 ft (2,270 m) above the lakeshore in only 3 horizontal miles (4.8 km).[4]Nohokomeen Glacier nearly fills the cirque on the upper north slopes of the mountain.
History
Jack Mountain was first described by surveyor Henry Custer in 1859, and was named for prospector Jack Rowley who was active on Canyon Creek.[5] The first recorded ascent of Jack Mountain was made in 1904 by topographer E.C. Barnard.[5] By the 1980s climbing routes had been established on most ridges, glaciers, and directions, seven in total. Most are class 4 but some involve true technical climbing. All are long routes with a great deal of vertical gain,[4] meaning most parties take three to four days to climb the mountain.
The Jack Mountain area consists of one small thrust fault, and a few other normal faults, none showing any seismic activity. Jack Mountain was created when the Hozameen Range was thrusted over the younger Harts Pass formation to the east. Most likely caused by the Ross Lake Fault to the west. The lower flanks of the mountain to the west were created by the Ruby Creek Heterogeneous plutonic belt.[6][7]
^ abBeckey, Fred W. (1995). Cascade alpine guide : climbing and high routes. Vol. 2, Stevens Pass to Rainy Pass (2nd ed.). Mountaineers Books. pp. 196–199. ISBN978-0-89886-423-6.
