Boundary Ranges

Geobox | Range
name=Boundary Ranges
other_name=Alaska Boundary Range


image_size=275
image_caption=View of the Juneau Icefield.
country=Canada
country1=United States
region=British Columbia
region1=Alaska
parent=Coast Mountains
geology=
geology1=
geology2=
orogeny=
highest=Mount Ratz
highest_elevation=3090
highest_lat_d=57|highest_lat_m=23|highest_lat_s=35.2|highest_lat_NS=N
highest_long_d=132|highest_long_m=18|highest_long_s=11.2|highest_long_EW=W


map_caption=Location map of Boundary Ranges; marine shoreline-boundary not shown
map_size=275

The Boundary Ranges, also known in the singular and as the Alaska Boundary Range, are the largest and most northerly subrange of the Coast Mountains. They begin at the Nass River, near the southern end of the Alaska Panhandle in the Canadian province of British Columbia and run to the Kelsall River, near the Chilkoot Pass. Beyond them to the west are the Alsek Ranges of the Saint Elias Mountains, while to their east are the Skeena Mountains, Stikine Plateau and Cassiar Mountains of the Interior Mountains complex that lies northwest of the Interior Plateau. To their northeast are the Tagish Highland and the Tahltan Highland.

The Boundary Ranges include several large icefields, including the Juneau Icefield, between the Alaska city of the same name and Atlin Lake in B.C.; and the Stikine Icecap, which lies between the lower Stikine River and the Whiting River. Some of the highest mountains in the Boundary Ranges are: Mount Ratz, 3090 m (10138 ft), Chutine Peak, 2910 m (9547 ft), and Devils Thumb, 2766 m (9077 ft), all in the Stikine Icecap region; and Devils Paw, 2593 m (8507 ft), in the Juneau Icefield. (There are other peaks in the Stikine Icecap higher than 2600 m but they have relatively low topographic prominence.)

Despite the height of Mount Ratz and its neighbours, most of the Boundary Ranges are considerably lower than the Pacific Ranges of the southern Coast Mountains. The larger icefields of the Boundary Ranges are at a much lower elevation than their southern counterparts in the Pacific Ranges because of the difference in latitude.

Physiographically, they are a section of the larger Pacific Border province, which in turn are part of the larger Pacific Mountain System physiographic division.

The granitic intrusions that form the Boundary Ranges are remnants of a Late Cretaceous volcanic arc system called the Coast Range Arc.

ub-ranges

*Cheja Range
*Chechidla Range
*Chutine Icefield
*Adam Mountains
*Ashington Range
*Burniston Range
*Dezadeash Range
*Florence Range
*Halleck Range
*Juneau Icefield
*Kahpo Mountains
*Kakuhan Range
*Lincoln Mountains
*Longview Range
*Peabody Mountains
*Rousseau Range
*Seward Mountains
*Snowslide Range
*Spectrum Range
*Stikine Icecap

External links

* [http://www.bivouac.com/ArxPg.asp?ArxId=1641 Boundary Ranges] of the Canadian Mountain Encyclopedia

References

*S. Holland, "Landforms of British Columbia", Province of British Columbia, 1976