sq-events sq-newsletter       sp-brochure-3

      Close to Heaven… Down to Earth

 



The Dakota Wall

The Dakota Wall is a formation of Dakota sandstone that stretches all along
the Front Range of the Rocky Mountains. During the Laramide Orogeny
(about 65 million years ago), the great mountain building forces that created Front
Rangia (part of the Ancestral Rocky Mountains) pushed upwards along this line and
the Dakota formation broke and turned vertical. Over millions of years the Ancestral
Rockies were weathered and eroded back into flatland but sections of the Dakota
Wall remained. Some portions of this older wall can still be found along the west
side of the Sangres in the San Luis Valley.

About 30 million years ago the process that built the modern Rockies about 50 miles
east of the Ancestral Rockies began. This process saw the creation of the Sangre
de Cristos. The Sangres are fault block mountains – there are faults along both
the east and west side of the mountains and the mountains themselves were raised
up in one big chunk of rock. Along the fault line on the east side of the mountains,
the Dakota formation again was broken and turned upright. These are the great sandstone
walls we see when travelling up the valley from Stonewall, over Cuchara Pass, through
the Cuchara River Valley and on up into La Veta Pass, Pass Creek Pass and northern
Huerfano County. In many places along this journey you can see where the ground
was actually folded and broken by the pressures along the fault line.

The Wet Mountain Valley is a fault block valley in that there are faults along the
east and west sides of the valley, and the valley floor dropped when the Sangres
rose. There are sections of the Dakota Wall visible above ground along the east
side of the valley, in the western foothills of the Wet Mountains. The major mass
of the Wet Mountains themselves was put in place during the Colorado
Orogeny
(some 1.7-1.8 billion years ago), about the same time as the
Mt. Blanca Massif and the Front Range around Pike’s Peak came into existence.

Other places where the Dakota Wall sticks out above ground are the Flatirons near
Boulder, Garden of the Gods near Colorado Springs, and the Stonewall near Cerrillos,
New Mexico.