geology

علوم زمین شناسی(جامعه زمین شناسان سولدوز)

Geologists examine Folsom deposits at Lubbock Lake, 1949.

A woman cuts strips of mammoth (Ice-Age elephant) meat on a hide, perhaps to be carried elsewhere for dinner. In the background, the beast is being carved up.

Folsom point found in place amid bones of extinct bison, June,1951.

Geoarcheologist Vance Holliday points out new evidence to TAS Field School Director Eileen Johnson.

For over 13,000 years the inhabitants and visitors to the Llano Estacado (Staked Plains) have frequented a locale known today as the Lubbock Lake Landmark. Until recently the main attraction was a major spring that flowed out of the Ogallala aquifer and into Yellowhouse Draw. The abundant water and sheltered draw was a haven for plants and animals. The water, plants, and animals drew humans, beginning with Clovis hunters and their families and continuing right on up into historic times, each leaving behind a few traces. The end result is an archeological record that has few parallels in the southern High Plains—layer after layer reflecting changing climates, environments, and cultures. Archeologists and other scientists have been studying the Lubbock Lake site for over 65 years and there is still much to be learned from this remarkable locale.

The place takes its name from a reservoir created in the 1930s in a U-shaped bend of Yellowhouse Draw, a tributary of the Brazos River. Up until the late 1880s, a natural, spring-fed lake existed in this same area. In the early 1900s, the springs began to dry up, the victim of too many thirsty people and their bountiful crops. In the late 1930s a project to dig out (and hopefully renew) the springs turned up Folsom points and other evidence of Paleoindian peoples. This led to the first archeological digs in 1939 and 1941 under the sponsorship of the Works Progress Administration (WPA). To run the excavation, W. Curry Holden, Director of the West Texas Museum (now the Museum of Texas Tech University) hired Joe Ben Wheat, a young Texan who would later become a noted Paleoindian expert. But everywhere the WPA crew dug, they soon hit water. While the springs never came back, the water table had been raised temporarily by the creation of the artificial reservoir. The Folsom deposits lay deep below the water table and only a few Paleoindian artifacts were recovered.

By the late 1940s, irrigation wells had drawn down the water table considerably lower, making the Folsom-age deposits accessible. Holden permitted new excavations to be carried out under the direction of E.H. Sellards, Director of the Texas Memorial Museum (TMM) at UT Austin. Sellards and his TMM teams had been exploring a series of "Early Man" sites including the famous Blackwater Draw in eastern New Mexico. Geologist Glen Evans and paleontologist Grayson Meade were in charge of the intermittent field work between 1948-1955 at Lubbock Lake. The main excavations were undertaken in 1950-1951. Taking advantage of the lower water tables and the almost vertical walls of the dredged-out waterway, Evans and Meade were able to document a complex sequence of natural and cultural deposits including bone beds associated with Folsom artifacts. Glen Evans' color photographs can be seen in the TMM 1950-1951 Photo Gallery.

Leg bone from extinct bison found in Bed 2, notable for the finely banded layers of diatomite, pond deposits of once-celled, algae-like organisms. Photo by Glen Evans, 1951, courtesy Texas Memorial Museum.

Leg bone from extinct bison found in Bed 2, notable for the finely banded layers of diatomite, pond deposits of one-celled, algae-like organisms.

Since 1972, the Lubbock Lake Landmark has been investigated by archeologist Dr. Eileen Johnson and geoarcheologist Dr. Vance Holliday and their students and associates. Field research has taken place almost every summer. The hallmark of their work has been meticulous documentation borne out of the realization that at Lubbock Lake most archeological deposits are the result of one-time events. Here the smallest trace can be a crucial clue to unraveling a "day-in-the-life" occupational episode—a bison kill, an overnight camp, a meal—sealed by the almost unbroken deposition of wind-borne dust, overbank flood mud, or pond and marsh deposits.

Lubbock Lake is now a state and federal historic landmark protected by a 336-acre preserve on the north side of the city of Lubbock, Texas. The park contains the Lubbock Lake Landmark (which includes a series of nearby archeological locales along Yellowhouse Draw), an interpretive center, and a research center operated by the Museum of Texas Tech University.

Today anyone can visit the interpretive center, see the incredible outdoor display of life-size bronze statues of Ice-Age animals, and sign up to participate in workshops and tours. This is one of the most accessible archeological and paleontological sites in Texas.. The interpretive center has a very active public education program that involves thousands of school children in the region every year. Check out the Lubbock Lake Landmark website for details.

You can get a closer look now at some of the vivid "day-in-the-life" recreations created by artists from the Texas Parks and Wildlife Department for the Lubbock Lake Landmark Interpretive Center in our special Mural and Diorama Gallery.

Under the archeological leadership of Dr. Eileen Johnson, the Texas Archeological Society (TAS) held its 33rd annual field school at Lubbock Lake Landmark June 3-11, 1993. Some 225 TAS members carried out site surveys and excavations at various locales within the Landmark and at several ranches elsewhere in the area. The biggest challenge was the relentless wind and the dusty bone-dry conditions it brought. The campers' tents "shook and flapped, and some collapsed" as Dr. E. Mott Davis put it. In hindsight, it seems fitting that those taking part in the field school had to face the exact same forces of nature that shaped the Lubbock Lake Landmark throughout its history. You can get a good look at many of the activities in the TAS 1993 Photo Gallery.

Lubbock Lake Reservoir dredged out and dried up, August, 1950. Unidentified man stands above exposure where Folsom deposits were found.

Click images to enlarge

Folsom points from TMM excavations. The specimen on the left and the one on the right are casts of the originals.

Archaic hunters spring up from the grass to hurl darts with atlatls at bison at the lake's edge. The hunters disguised themselves as wolves and slowly crept closer before springing. On the horizon family members watch the scene hoping for a successful hunt.

Jaq Jaquier takes note as TAS members begin a new excavation at Lubbock Lake Landmark.

Lubbock Lake Main TAS 1993 Photo Gallery TMM 1950-1951 Photo Gallery Mural and Diorama Gallery Credits & Sources

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1 October 2001

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