Through the centuries, various tribes of Plains Indians, including Apache, Cheyenne, Arapahoe, Kiowa, and Comanche, made use of the canyon as a camping ground. After the arrival of the white man, the canyon became a favorite resting place for buffalo hunters and Indian traders who travelled the Plains. White men first established residence there in 1876.
The last Indian battle in Texas was fought in the canyon south of the Park. Col. Ranald Mackenzie and his raiders, on September 25, 1874, attacked a large encampment of Comanche, Cheyenne, Kiowa, and Arapahoe in the canyon. They destroyed about 100 lodges and 1400 horses and mules. The damage inflicted was severe and by the following spring most of the Indians were returned to the reservation in Oklahoma.
The age of the earth is calculated in terms of billions of years. For convenience, geologic time is divided into units, called PERIODS, of different lengths (Figure 1). Sediments deposited during each period and the fossilized remains of animals and plants found in these sediments give a partial record of the events and life of that period.
A nearly homogeneous (uniform composition) rock layer may be identified as a FORMATION. Formations are usually spread over a wide area like a large blanket and are stacked on top of each other with the oldest at the bottom and the youngest at the top. When viewed in the walls of the canyon, they resemble a huge layer cake and may be traced along the canyon walls.
[Illustration: Figure 1. GEOLOGIC MAP OF PALO DURO CANYON]
[Illustration: Figure 2. Stratigraphic section at Palo Duro Canyon with Geologic Time-scale for reference.]
GEOLOGIC TIME-SCALE AGE M.Y. CENOZOIC QUAT. HOLOCENE PLEISTOCENE 2 TERTIARY PLIOCENE 13 MIOCENE 25 OLIGOCENE 36 EOCENE 58 PALEOCENE 63 MESOZOIC CRETACEOUS 135 JURASSIC 181 TRIASSIC 230 PALEOZOIC PERMIAN 280 PENNSYLVANIAN 310 MISSISSIPPIAN 345 DEVONIAN 405 SILURIAN 425 ORDOVICIAN 500 CAMBRIAN 600 PRECAMBRIAN
The lowest and oldest exposed formation in Palo Duro Canyon is the Quartermaster. It was deposited near the edge of a shallow sea that occupied a wide area in Texas some 280 to 230 million years ago (Figure 3). This was during the Permian Period, the last period of the Paleozoic Era. The sediments in the park area were carried from the east and deposited in a nearshore environment. Sedimentary structures, such as crossbeds and ripplemarks, are present throughout the Quartermaster Formation. Halite casts suggest that there was a high rate of evaporation as sedimentation occurred. Gypsum (altered anhydrite) is also interpreted to be an evaporite deposit. The gypsum is now seen as horizontal white layers of alabaster and satin-spar varieties within the Quartermaster Formation.