any geologists out there want to tell me otherwise....
words below from here (to give proper reference...)
Most slot canyons are remote, hidden and difficult to reach and explore, but this only adds to their appeal; one can get a good idea from a photograph, but this is no substitute for visiting in person. The canyons tend to be dry for most of the year but receive occasional flash floods of great force, most frequently during the late summer months. It is these sudden torrents of water, carrying logs, stones and other debris that have been cutting through the relatively soft rock for millions of years, resulting in a great variety of colourful rock shapes and forms.
In general, true slot canyons are found only on the many rivers and their tributaries that ultimately flow into Lake Powell, in Utah.
ok---have a nice day!