The U-S Geological Survey is advising residents in southeastern Minnesota and northeastern Iowa to be on the lookout for a low-flying airplane and a helicopter during the month of January.
                 
The Post-Bulletin of Rochester reports the vehicles will be involved in an aerial survey to study rock layers in order to create state-of-the-art subsurface maps and assess the area's minerals for possible mining and water resources.

The survey will center around the Spring Grove area with the plane and helicopter flying between 100 and 500 feet off the ground.

The U-S Geological Survey says it will be the first high-resolution ground survey to take place in the area.

Flights will occur during the daylight hours.