Revealed to the world in 1977 this is the first map of the earth s ocean floor.
First map of the ocean floor.
Today we know more about the topography of the moon and mars than we do about our own planet s sea floor.
But in the 1950s and 60s when this feat of cartography was being assembled by us cartographers marie tharp and bruce heezen we knew almost nothing.
Each consist of three sheets a base bathymetric map.
Typically finely wrought ocean maps have been the result of extensive sonar.
This graphic shows several ocean floor features on a scale from 0 35 000 feet below sea level.
This is expensive and time consuming so sonar maps are mostly only made of places where ships spend the most time.
To complete a map of earth s ocean floor you ve got to take to the high seas by boat.
The publication of heezen and tharp s physiographic map of the north atlantic in 1957 was the first map of the sea floor that enabled the general public to begin to visualize what the ocean floor really looked like.
This product is intended to aid fishermen and those needing seafloor features and potential fishing grounds.
The following features are shown at example depths to scale though each feature has a considerable range at which it may occur.
Topographic maps of the sea floor produced at a 1 100 000 scale that contain loran c rates bottom sediment types and known bottom obstructions.