Obsidian Cliff - Yellowstone N.P., Wyoming
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Volcanoguy
N 44° 49.444 W 110° 43.751
12T E 521409 N 4963442
The Obsidian Cliff area is a prominent cliff of volcanic glass which is also a National Historic Landmark.
Waymark Code: WMD6AQ
Location: Wyoming, United States
Date Posted: 11/25/2011
Views: 12
The Obsidian Cliff flow is a glassy flow-banded rhyolite which was erupted about 183,000 years ago along a set of north-trending faults known as the Norris Mammoth corridor along which other post caldera rhyolites have also erupted. The flow covers over five square miles with the actual Obsidian Cliffs being located along the northwestern edge of the flow where a lobe of the flow filled the former channel of Obsidian Creek. Since the eruption, Obsidian Creek has carved a new channel along the contact between the Obsidian Creek flow (to east) and the older Lava Creek Tuff (to west). This new channel is known as Obsidian Canyon and the Obsidian Cliff form the east wall of the canyon.
Sources of info on Obsidian Cliff flow:
28th International Geological Congress Field Trip Guidebook T305 - Snake River Plain-Yellowstone Volcanic Province, 1989
Track of the Yellowstone hotspot: Young and ongoing geologic processes from the Snake River Plain to the Yellowstone Plateau and Tetons - L.A Morgan, K.L Pierce and W.C. Pat Shanks, 2008
The Quaternary and Pliocene Yellowstone Plateau Volcanic Field of Wyoming, Idaho, and Montana - U.S.G.S Professional Paper 729–G - Robert L. Christiansen, 2001
The coordinates for this waymark are located at the historic Obsidian Cliff Kiosk, the only official parking area along the Obsidian Cliff.
Obsidian Cliff, located in northwestern Yellowstone National Park, is a geologically distinctive natural feature that has been used as a raw material source for high quality obsidian tools for at least 11,000 years. The Obsidian Cliff lithic source area has been regarded as a prominent prehistoric quarry since its recognition in the 19th century. The volcanic glass was quarried and made into many types of tools, from simple flake tools used to cut hides or butcher animals for meat, to arrowheads or spear points, to large ceremonial artifacts. Obsidian Cliff obsidian can be found in archeological sites from the Middle Rockies into western Canada, across the Great Plains into the Midwest, as well as the Columbia Plateau, and possibly the Great Basin. By using trace-and bulk-element geochemistry techniques, archaeologists can trace obsidian artifacts to known geological sources. Obsidian from Obsidian Cliff was imported and utilized for ceremonial purposes by peoples of the Hopewell Culture in the Ohio River valley from around 1,600 to 2,200 years ago. The Obsidian Cliff was placed on the National Register of Historic Places and National Historic Landmark List on June 19, 1996.
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