An ancient stone tool found in the high desert of eastern Oregon could be up to 15,800 years old.
The agate scraper might be older than any human civilization known to exist in the western continental United States. The ancient tool was created from a piece of orange agate, not found anywhere in eastern Oregon.
Rimrock Draw Rockshelter near Riley, Oregon experienced significant ash fall from the fall of Mount St. Helens that occurred 15,800 years ago. The hand tool was discovered eight inches beneath this layer, around 12 feet under the surface of the ground.
"The discovery of this tool below a layer of undisturbed ash that dates to 15,800 years old means that this tool is likely more than 15,800 years old, which would suggest the oldest human occupation west of the Rockies," Scott Thomas, BLM Burns District archaeologist, said.
The Clovis People were traditionally believed to be the first culture to migrate from Asia into North America. That movement is usually dated to 13,000 years in the past, the age of the oldest known Clovis artifacts. If the age of the tool is confirmed by additional research, this find would join a handful of other archaeological finds that pre-date the Clovis culture.
Analysis of blood samples found on the tool shows the scraper was used to process material from a form of bison, probably an ancestor of modern buffalo known as Bison antiquus. At this time in history, the area was populated by camels, mastadons, and mammoths. This find appears to date to the end of the Pleistocene era.
The U.S. Bureau of Land Management, which owns the land on which the tool was discovered, announced the finding. Another area in Oregon operated by the agency, Paisley Cave, holds the oldest direct physical evidence of human habitation in North America. Human feces discovered in that natural shelter has been dated to more than 14,000 years in the past, ten centuries before the Clovis People arrived in the New World. Another find that is the same age as the one at Paisley Cave was previously discovered at Monte Verde in Chile.
Archaeological finds at the area were first identified by Thomas when he was out for a walk and he noticed sage brush growing in front of an old lava flow. This is often a tell-tale sign of deep sedimentary deposits. An ancient steam bed could have provided water to a settlement there, and evidence was found of frequent controlled fires, which may have been used for cooking.
Future research will examine whether or not ash covered the entire area around the find or if the artifact could have slipped through the layer.
Photo: Bureau of Land Mangement | Flickr
