The Lake Theo Site (41BI70) is three miles north of Quitaque, Texas, in Caprock Canyons State Park in southeast Briscoe County. Its cultural deposits lie buried in the south rim of Holmes Creek, a tributary of the Little Red River. Frank Tow of Amarillo first reported the site to the Panhandle-Plains Historical Museum in 1972. It was a small area covered by bleached buffalo bones and several Folsom point fragments along an eroded edge of the canyon rim. A visit to the site in October 1972 by museum personnel confirmed the presence of Folsom points, associated with Pleistocene age bison. With funds provided by the Texas Historical Commission the Panhandle Plains Historical Museum conducted test excavations during the summer and fall of 1974. The tests revealed a bone bed extending to the south from the eroded edge for an unknown distance. Further funding from the Texas Parks and Wildlife Department and the National Park Service permitted additional testing during the fall of 1977. The primary purpose of this phase was to determine the extent of the site and obtain additional artifacts for display and study.
The site, over an acre in extent, proved to have multiple components with a thin scattering of Archaic age artifacts on the surface. The deepest deposits produced Folsom and Plano age artifacts associated with two different Pleistocene bison bone beds covered by twelve to eighteen feet of overburden. It is believed the site was a butchering camp. The dart points, bifaces, and grinding implements found on the surface of the site suggest a Late Archaic occupation dating around 1,000 B.C. to A.D. 500. A single carbon-14 date of 9,360 ± 170 B.P. was obtained on bone samples from the Folsom bone bed. A second test on bone associated with the Plano points provided a date of 8,010 ± 100 B.P. Lithic artifacts from the site include projectile points, end and side scrapers, gravers, knives, projectile-point preforms, and abraders. Several small unidentifiable pieces of worked bone were also recovered. Only a small portion of each of the two bone beds was explored. A ceremonial or religious feature discovered during the 1974 investigations consisted of three left bison mandible halves, a left and right tibia, a right femur, and a thoracic vertebral spine, all placed vertically in a small round hole at the bottom of the Folsom bone bed. The entire collection and the original records are located at the Panhandle-Plains Historical Museum in Canyon. A copy of the records is on file at the Texas Historical Commission in Austin, Texas.