Wednesday, January 28, 2009

2/11 Obsidian: History Through the Volcanic Glass Window at Hillsboro Main

photo, Dennis Jenkins
Archeologist Dr. Dennis Jenkins from the University of Oregon will discuss this beautiful volcanic igneous glass and how it can give us a fascinating glimpse into the pre-history of Oregon.

Flows of obsidian, a natural glass produced by many volcanoes in Oregon, contain a unique chemical signature that enables archaeologists to trace artifacts back to the volcano of origin. Obsidian is also an unstable mineral that begins absorbing molecular water soon after a fresh surface is exposed to the atmosphere, a process that produces a detectible rind that thickens at a predictable rate under various site conditions, producing a “hydration clock” that tells the age of each artifact and flake.

Archaeologist Dennis Jenkins will discuss the invaluable information about our culture stored within nature in “Obsidian: History through the Volcanic Glass Window.” Hillsboro Main Library is pleased to host this Oregon Chautauqua from the Oregon Council for the Humanities. This free, public program will take place on Wednesday, February 11 at 6:30pm at Hillsboro Main Library, 2850 NE Brookwood Parkway, Hillsboro.

Obsidian artifacts yield a treasure-trove of information about prehistoric lifeways and the development of sociopolitical areas in central Oregon across fifteen thousand years of prehistory. Archaeologist Dennis Jenkins presents a fascinating look at the trail of information left by this beautiful volcanic glass.