The Medicine Bow Mountains resulted from continental compression during the Laramide Orogeny. Beginning about 70 million years ago, the Rockies began uplifting along thrust faults that broke up the Precambrian granite of Earth's crust. By 50 million years ago, all of Wyoming's major mountain ranges were elevated and the major basins defined. Rocks exposed along the flanks and peaks of the Medicine Bow Mountains span the Precambrian to modern, with the peaks composed of 2.4-2.0 billion year old Medicine Peak Quartzite. This rock was once a shallow marine sand deposit that has since been compressed and heated during burial, forming the metamorphic rock, quartzite. What may be traces of multicellular animals are preserved in this rock, making it of particular interest to paleontologists.