Olson's body was found by a landowner on Saturday in the township of Ravenna in Dakota County, and officials said they believed she had not been in that location for more than 36 hours.
Olson has been missing since December 28, according to WQAD TV. She was last seen at a gas station in Rock Island, Ill., late that afternoon, and friends and family launched an intensive effort to find her. They set up a Facebook page, posted flyers and billboards publicizing her disappearance, organized several searches and offered rewards for information.
A spokesman for Davenport Police confirmed they had been in contact with Dakota County authorities, but he declined to offer any details about that contact, according to WQAD.
The medical examiner said the cause of her death is pending further investigation.