Rock Art Scanning
Jeffers Petroglyphs
Rock carvings are among the most enduring forms of human expression. American Indians have traveled to the Jeffers Petroglyphs, in Southwestern Minnesota, for more than 25,000 years to worship and to record the story of their lives. In fact, Minnesota's recorded history begins at this place. The earliest of over 4000 carvings at Jeffers Petroglyphs were created 7000-9000 years ago. The most recent were made in the last 150 to 250 years. These rock carvings record historic events, parables, and prayers of American Indians whose descendants still practice the traditional spiritual system that created the carvings. This time span places Jeffers among the oldest continuously used sacred sites in the world, and its varying styles of carvings represent cultures originating across North America.

At the Jeffers site, thousands of individual 3D scans have been taken using a Breuckmann white light laser scanner. The two primary objectives of the Spring 2012 3D Laser Scanning Internship were to 1) use those thousands of scans to create 3D models of key expanses of rock face, and 2) inspect each of those models, selecting individual petroglyphs and creating 3D PDF files representing each one. All told, roughly 700 files were created along with detailed classification notation for each. The majority of petroglyphs found at Jeffers are of geometric shapes, or representations of animals. Animal (foot)prints and tools, such as atlatls are also common.

On the left is a petroglyph from Jeffers that resembles a human figure.