I have spoken of these north-and-south faults as if they were fractures;
and usually they are fractures, but in some places they are flexures.
The Echo Cliffs displacement is a flexure. Just over the zone of flexure
a long ridge extends from north to south, known as the Echo Cliffs. It
is composed of a comparatively hard and homogeneous sandstone of a later
age than the limestones of the Marble Canyon Plateau west of it; but the
flexure dips down so as to carry this sandstone which forms the face of
the cliff (presented westward) far under the surface, so that on the
east side rocks of still later age are found, the drop being several
thousand feet. The inclined red sandstone stands in a ridge more than 75
miles in length, with an escarped face presented to the west and a face
of inclined rock to the east. The western side is carved into beautiful
alcoves and is buttressed with a magnificent talus, and the red
sandstone stands in fractured columns of giant size and marvelous
beauty. On the east side the declining beds are carved into pockets,
which often hold water. This is the region of the Thousand Wells. The
foot of the cliffs on the east side is several hundred feet above the
foot of the cliffs on the west side. On the west there is a vast
limestone stretch, the top of the Marble Canyon Plateau; on the east
there are drifting sand-dunes.

The terraced land described has three sets of terraces: one set on the
east, great steps to the Kaibab Plateau; another set on the west, from
the Great Basin region to the Kaibab Plateau; and a third set from the
Grand Canyon northward. There are thus three sets of cliffs: cliffs
facing the east, cliffs facing the west, and cliffs facing the south.
The north-and-south cliffs are made by faults; the east-and-west cliffs
are made by differential degradation.