Prehistoric Archaeology & Geological History

Prehistoric Archaeology Video

As you roam around the red rock formations on Ken-Caryl Ranch, have you wondered about life in this area thousands of years ago? The Ken-Caryl Ranch Historical Society has produced a short video describing some archaeological sites and prehistoric life in our community. Jack Warner, a member of the Colorado Archaeological Society and also a resident of Ken Caryl Ranch, provided the information and many of the pictures used in the production.

Geological History

The story of the events that contributed to the formation of Ken-Caryl Ranch is told by information in the rocks that outcrop in this area. Rocks which range in age from recent to those as old as two billion years are present on the Ranch.

The earliest history of the Ranch is recorded along the mountain front west of the Manor House, marked by the sharp break in topography rising to Tincup and Beacon Hill. Tincup is the highest mountain west of the Manor House. Beacon Hill is the shoulder on the south side of Tincup. These rocks were formed into large mountain ranges intruded by great molten masses of granite with the resulting heat and pressure altering the rock to the metamorphic rock we see today. Erosion leveled these ranges to a flat featureless plain. All these events took place prior to the beginning of the Paleozoic Era, some 600 million years ago.

Information on the events of the next 300 million years is lacking on the Ranch, although we know from nearby areas that rocks were deposited, but again stripped off by erosion.

The Ken-Caryl Ranch region was a shoreline with abrupt topography to the west and a myriad of streams carrying coarse sediment into a sea to the east 300 million years ago. These coarse sediments hardened into the red rocks of the Fountain Formation. In Lyons time the sea returned and deposited sandstone that forms the hogback east of the Equestrian Center. As the sea deepened, muds and limey muds were deposited resulting in the shale and limestone of the Lykins Formation, and the valley between the Lyons and Dakota Hogbacks.

The sea again withdrew to the east, leaving a low coastal plain through which sluggish streams wandered. This plain became a swampy paradise for dinosaurs during the time of the Morrison Formation. The great reptiles continued to roam this region for the next few million years until the seas again returned to form the beaches of the great hogback maker, the Dakota sandstone. Evidence of the dinosaurs walking these ripple marked beaches can be seen along Alameda Parkway as it crosses the Hogback north of the Ranch. The ripple marked beaches and the dinosaur footprints are preserved in stone.

The sea advanced and drove the dinosaurs to the west. Thousands of feet of mud and limey mud were deposited in this sea. At the top of this layer of mud are the coals and sands of the Fox Hills Formation and the reason for the name Coal Mine Road. Sharks and shellfish were present in this sea and their remains can be found in the limestone of the small Niobrara Hogback east of the Dakota Hogback.

About 70 million years ago the sedimentary layers next to the mountain front were bent sharply upward. Great masses of molten granite, deep within the Earth, were inĀ­truded into the rapidly rising mountains to the west. Some of this material found its way to the surface as lava flows and volcanic ash. At this time, a small wrinkle formed to the east of the mountains and when the erosion process was through there was a valley which later was named the Ken-Caryl Valley.

The same processes would also conduct the final shaping of the hard sandstones and limeĀ­stones into the hogbacks, and the softer shales into the intervening valleys and produced the Front Range topography we see around us today.

Written by the Ken-Caryl Ranch Historical Committee of 1990 & 1997.