Wednesday, October 22, 2014

Cliffs of the Ruby Mountains: Mt. Gilbert

The glacially carved cliffs around Camp Lamoille are truly spectacular — and while we were, now nearly a month ago — they provided us with constant fascination and wonderment amid the ever-changing light and cloud effects. To the south of us, besides Ruby Spire and the Wolf's Ear (seen in this earlier post), Mt. Gilbert towered over us at 11,120 feet.
A view of Mt. Gilbert, the highest point near an unnamed spire, as seen on the second day from the trail near the South Fork beaver ponds.
A closer view of Mt. Gilbert and the same spire;
photo taken on the second day from the main part of camp.
In the view above, you can see a couple spots of snow high on the cliffy slopes, probably left over from the previous winter (2013-2014).

Mt. Gilbert is a pyramid-shaped peak, possibly qualifying as a glacial horn, AKA pyramidal peak (British usage?). As you can see below, it's bounded on the west by the large bowl-shaped head of the glacially carved, U-shaped Seitz Canyon; it's bounded on the northeast by a high, well-defined cirque; and it's bounded on the southeast by an irregularly bowl-shaped area, also a cirque.
Topo map from USGS TNM 2.0 Viewer (link), with Mt. Gilbert right of center.
Same map, with the outlines of three circular depressions or bowls formed by glaciers. As you can see, the west side of Mt. Gilbert is essentially one arête. Other horns and arêtes are present in the topo image.
It just occurred to me that the unnamed spire might also be a small horn, but only if the indentation into the cliff below it to the east consists of a small cirque formed from a small hanging glacier (I wish the USGS would provide individual links in their Glossary of Glacial Terminology, but they don't).
What do you think? Is it a horn?
Rain and hail from an intense, long-lasting embedded thunderstorm (or set of storms), pounded the Lamoille Canyon area late on the second afternoon and long into the second night. When we awoke the morning of the third day, the tops of the cliffs and peaks around us were well dusted with snow:
Mt. Gilbert with snow, as seen from camp on the morning of the third day.
A closer view from the same time, same location. The snow highlights the foliation of the metamorphic rocks — gneiss and marble,
possibly with sill-like intrusions of granite.
USGS Glossary of Glacier Terminology

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