27 Experts Dig into Science, Bone Count Tops 4,000

A group of 27 scientists has joined the 50-person dig team at the Ice Age fossil site near Snowmass Village. With one week left in the dig at Ziegler Reservoir, the fossil excavation is accelerating to its completion. Crews from the Denver Museum of Nature & Science have now pulled 4,056 fossils from the site since work resumed this spring. 

"While much of our activity has centered around salvaging fossils from the core of the dam site, we are now entering a phase of intense scientific investigation about the origin of the Ice Age lake and its history," said Dr. Kirk Johnson, the leader of the excavation team and vice president of the Research and Collections Division at the Museum.

The scientists are among 37 experts from 15 institutions in the United States, Canada, Spain, and England who are involved in the project and whose work will make the most of the site's scientific potential. Their onsite activities include collecting cores of sediment from the ancient lake bed, studying the sediment that fills the ancient lake, making high-resolution scans of in-place fossils, and collecting various samples for analysis.

"Sediment cores are a very important way for us to sample the complete sequence of lake sediments and preserve them for future research," said Johnson. "They are a critical piece of the science that can be archived and studied for climate information such as temperature changes and drought." 

A small drill rig, operated by scientists from the U.S. Geological Survey offices in Lakewood, Colorado, is drilling 20 to 30 feet into the sediment and pulling cores that are two inches in diameter so scientists can access and study all the sediment layers that accumulated in the ancient lake. These cores will first be studied in Denver and then move to the University of Minnesota where they will be permanently stored at the National Lacustrine Core Facility. Funded by the National Science Foundation, this facility was established in 2000 to archive high-quality sediment cores from lakes all around the world and make them available for research.

A team from the Colorado Water Science Center is collecting LIDAR ground laser scans of select fossils. These scans are precise to within a few millimeters and will allow scientists to reconstruct parts of the site with high resolution 3D models. These scans are particularly useful for mapping areas where numerous fossils occur together and where this information may shed light on the burial history of the fossils. For example, the team has located a portion of the ancient lake shoreline, which contains a partial mastodon skeleton interlocked with driftwood logs up to 35 feet long. The LIDAR scans provide a detailed map of the site that allows the dig teams to document the site rapidly before continuing their excavation. 

The team of scientists is also gathering thousands of samples from the site, to study fossil pollen and spores, insects, plants, and the character and chemistry of the lake sediment. These samples will provide critical information about the ecology and climate of the ancient landscape. By working together at the site, the different specialists are able to coordinate their sampling and assure that the scientific results will be integrated. Moving forward, the Denver Museum of Nature & Science will serve as the coordinating organization to ensure that the scientific team capitalizes on the amazing opportunities presented by this sequence of high-elevation ice age ecosystems.

Project Updates

Get caught up on everything that happened in the field, learn what scientists are doing to preserve the bones, and find out the latest discoveries from our team of experts.

Learn more

Discovery Timeline

See how this amazing discovery unfolded, from the first fossil to the last day of the dig.


Digging Snowmastodon

Order Digging Snowmastodon: Discovering an Ice Age World in the Colorado Rockies, a first-person account of the historic Ice Age fossil find, today!

Learn more

^ Back to Top