Tribal and state partners digitally preserve Michigan petroglyphs
Last updated 11/24/2018 at 4:48pm
LANSING, Mich.-Tribal and state partners are working closer than ever to care for and preserve more than 100 petroglyphs carved into a large sandstone outcrop on Michigan's Cass River floodplain using laser technology.
"We created digital models of the Sanilac Petroglyphs with harmless pulses of light that detect and measure the 3D world," said Stacy Tchorzynski, an archaeologist at the State Historic Preservation Office (SHPO) and project manager for the Sanilac Petroglyphs. "This is an ambitious collaboration between SHPO and MDOT, in partnership with the Ziibiwing Center of Anishinabe Culture & Lifeways, Saginaw Chippewa Indian Tribe of Michigan and the Michigan History Center, DNR."
MDOT specialists used terrestrial LiDAR (Light Ranging and Detection) and close-range photogrammetry–overlapping detailed photographs–to build digital models that will help document the site and track its preservation. The sandstone petroglyphs are fragile and subject to weathering and other environmental and human forces.
"People worldwide have carved images into stone to honor their ancestors, record teachings and mark important events," Tchorzynski said. "Sanilac Petroglyphs Historic State Park has Michigan's largest known collection of carvings, which likely date from within the last 1,400 years."