Teaching Petrology: Gallatin National Forest

Palisades Falls, Hylalite Canyon, Montana

This evening trip was to a campground in Hyalite Canyon, Gallatin National Forest, south of Bozeman. We walked up a trail to the lovely Palisades Falls, which cascades over Absaroka volcanics.

hyalite_canyon topo map

Map showing the access road and hiking trail to Palisades Falls.

TPW-2003-131

The Palisades Falls over a thick lava flow with nice columnar jointing.

TPW-2003-133

The lava flow in the image above is seen here at the top. It rests on top of a boulder conglomerate, probably a river deposit. The deposit is visible at the bottom right of this image. In the middle is a finer-grained deposit containing mostly angular and subrounded fragments in a finer-grained, perhaps muddy matrix. This may be a mudflow deposit, perhaps a lahar.

TPW-2003-129

Closer view of the lava flow base, the layers of rounded boulder conglomerate, and at the bottom the angular block deposit that may be a lahar.