American Indians lived in the canyon 300-800 years ago and left rock art which is visible on the canyon walls. Geologically scenic Vogel Canyon is a tributary of the Purgatoire River drainage.
The sedimentary layers of rock at Vogel Canyon indicate that this was a lake basin in the past. Alternating layers of tough, light grey limestone and soft, dark grey shale. The limestones are erosion resistant while the shales are easily weathered and crumbled, allowing the river to undercut the limestone beds and causing limestone slabs to collapse into the river.
The shales represent accumulations of mud in the ancient lake itself whereas the limestones represent accumulations of coarser, sand-textured sediments along the lake shore when water levels were low. The shales contain fossilized remains of algae, snails and tiny crustaceans known as "seed shrimp" and "clam shrimp." All of these species are common in quiet, shallow lakes. In contrast, the limestones contain impressions of large plant stems, dinosaur bones, trampled clams, scattered fish bones and lots of tracks. The limestones are also marked by ripple marks (caused by wave action) and by ooids (tiny, limey spheres) caused by wave action in shallow water.
This evidence supports the conclusion that the lake level fluctuated on a seasonal basis and also on longer term cycles covering decades and even centuries. The lake itself was probably 20 to 30 miles in diameter, shallow but with potable water most (if not all) of the time, and inhabited by a large variety of healthy flora and fauna of snails, algae, crustaceans and fish. The margins of the lake were partly or totally vegetated, the mud inhabited by clams and the whole area frequented by several types of dinosaurs. All in all, there's clear evidence of at least six times when dinosaurs visited this part of the shore of that ancient lake.
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