If you descend from 100 miles to about 5 miles above the Teton region,
the asymmetry of the range, the extraordinary variety of landscapes, and
the vivid colors of rocks become more pronounced.
Figure 2 shows a panorama of the Teton Range and Jackson Hole from a
vantage point over the Pinyon Peak Highlands. The rough steep slopes and
jagged ridges along the east front of the range contrast with smoother
slopes and more rounded ridges on the western side. Nestled at the foot
of the mountains and extending out onto the floor of Jackson Hole are
tree-rimmed sparkling lakes of many sizes and shapes. Still others lie
in steep-sided rocky amphitheaters near the mountain crests.
One of the most colorful flight routes into Jackson Hole is from the
east, along the north flank of the Gros Ventre Mountains. For 40 miles
this mountain range is bounded by broad parallel stripes of bright-red,
pink, purple, gray, and brown rocks. Some crop out as cliffs or ridges,
and others are _badlands_ (bare unvegetated hills and valleys with steep
slopes and abundant dry stream channels). In places the soft beds have
broken loose and flowed down slopes like giant varicolored masses of
taffy. These are mudflows and landslides. The colorful rocks are bounded
on the south by gray and yellow tilted layers forming snowcapped peaks
of the Gros Ventre Mountains.
These landscapes are the product of many natural forces acting on a
variety of rock types during long or short intervals of geologic time.
Each group of rocks records a chapter in the geologic story of the
region. Other chapters can be read from the tilting, folding, and
breaking of the rocks. The latest episodes are written on the face of
the land itself.