Millions of years of on-off ice ages have left behind a mix of different sediments.
Tharp with an undersea map at her desk. Rolled sonar profiles of the ocean floor are on the shelf behind her.
Lamont-Doherty Earth Observatory and the estate of Marie Tharp
Born on July 30, 1920, geologist and cartographer Tharp changed scientific thinking about what lay at the bottom of the ocean – not a featureless flat, but rugged and varied terrain.
A camera catches a huge Greenland shark in eastern Baffin Bay, near Disko Bay, Greenland.
Jonathan Fisher