Before leaving the base, a smartpad reads that the destination is the CHUCKCHI SEA, an area north of the Bering Straight, and geo-coordinates are for near the west-end of Herald Island. Herald Island is Russian and devoid of trees.
The trivia item below may give away important plot points.
At around 1:00:00 into the movie Mills activates one of the SAR units to understand their objective. Upon activation the sound used is similar to the sounds the alien ships in Battleship (2012) produce.