A geologic map is made to show the reader information about the geological formations of the land, including detailed information about the rocks below. Geologic maps are very important for geologists and others who need to know things about the land such as how old the different layers of the Earth in an area are,

The Head of the Charles is happening this weekend in Boston and Cambridge. Here's what to know about the course map, where to watch and road closures.

The USGS publishes a geological map that reveals the underground layers of the U.S. and supports environmental education and planning.