The victim has been identified at Gregory J. Mosher, 29, of Channahon, who was pronounced dead at 11:08 p.m. at Presence St. Joseph Medical Center in Joliet, according to the Will County coroner's office.
An autopsy conducted Thursday showed that Mosher died of multiple injuries that were the result of a "snowmobile mishap," the office said.
The accident happened an eighth of a mile west of Brandon Road, near the access point to the trail and the Brandon Road Lock and Dam on the Des Plaines River. There is also an access point to the trail in Channahon.
No information was available on what type of object Mosher struck that caused the accident. The case is being investigated by the Illinois Department of Natural Resources Conservation Police.