First Map Of The Ocean Floor

This graphic shows several ocean floor features on a scale from 0 35 000 feet below sea level.

First map of the ocean floor.

Seafloor mapping also called seabed imaging is the measurement of water depth of a given body of water bathymetric measurements are conducted with various methods from sonar and lidar techniques to buoys and satellite altimetry various methods have advantages and disadvantages and the specific method used depends upon the scale of the area under study financial means desired measurement. Continental shelf 300 feet continental slope 300 10 000 feet abyssal plain 10 000 feet abyssal hill 3 000 feet up from the abyssal plain seamount 6 000 feet. The following features are shown at example depths to scale though each feature has a considerable range at which it may occur. Revealed to the world in 1977 this is the first map of the earth s ocean floor.

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. We ve come a long way in ocean exploration since the days of the hms challenger launched in 1858. 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. This product is intended to aid fishermen and those needing seafloor features and potential fishing grounds.

These early maps based on hundreds of thousands of hand picked depths provided the context for the plate tectonics revolution. 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. This is expensive and time consuming so sonar maps are mostly only made of places where ships spend the most time. The last complete map was hand drawn in the 1970s.

To complete a map of earth s ocean floor you ve got to take to the high seas by boat. Marie tharp july 30 1920 august 23 2006 was an american geologist and oceanographic cartographer who in partnership with bruce heezen created the first scientific map of the atlantic ocean floor tharp s work revealed the detailed topography and multi dimensional geographical landscape of the ocean bottom. Each consist of three sheets a base bathymetric map. Typically finely wrought ocean maps have been the result of extensive sonar.