Travel Reference
In-Depth Information
turned the slopes to mud, mud slides came surging down the mountains, filled the valleys,
and hardened into conglomerate rock, a sedimentary rock that consists of fragments from
previously formed rock. The fragments range in size from tiny up to greater than fist size.
Over the millennia, other lava flows covered some of these sediments. After relatively
minor earth stresses fractured the rocks, rain and the freezing and thawing of water in the
vertical cracks eroded the rock to form cliffs or columns. The tops of the columns occur
where a layer of rock more resistant to erosion sheltered the underlying soft layers. Some
of these columns developed into the bizarre shapes called hoodoos.
Observers have used their imaginations in naming about 60 hoodoos. At one of them,
Chimney Rock, about 16 miles (26 km) west of Wapiti, the road goes close enough to re-
veal how the flat-lying layers of pebbly rock alternate with finer-grained sandy layers.
