Age Of Sea Floor Map

An international scientific team recently published a new map of the ocean floor based on earth s gravity field and it is a particularly useful tool.

Age of sea floor map.

Scientists use the magnetic polarity of the sea floor to determine the age. A digital age map of the ocean floor. A marine gravity map of the north atlantic ocean red dots show locations of earthquakes with magnitude 5 5 and they highlight the present day location of the seafloor spreading ridges and. The maps were created through computer analysis and modeling of new satellite data from esa s cryosat 2 and from the nasa cnes jason 1 as well as older data from missions flown in the 1980s and 90s.

Sio reference series 93 30 scripps institution of oceanography. Ages for ocean floor between the oldest identified magnetic anomalies and continental crust are interpolated by geological estimates of the ages of passive continental margin segments. Note that the youngest seafloor ages are found at the mid ocean spreading ridges where new rock is constantly coming up from under the crust to heal the rifts formed as tectonic plates move away from one another. The data is from four companion digital models of the age age uncertainty spreading rates and spreading asymmetries of the world s ocean basins.

New sea floor map for google earth january 13 2016 in late 2014 we had a look at a map of the ocean floor published by the scripps institution of oceanography university of california san diego. Very little of the sea floor is older than 150 million years. For that geologists date and study continental crust. Measurements of the thickness of marine sediments and absolute age determinations of such bottom material have provided additional evidence for seafloor spreading.

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 oldest sediments so far recovered by a variety of methods including coring dredging and deep sea drilling date only to the jurassic period not exceeding about 200 million years in age. Therefore seafloor dating isn t that useful for studying plate motions beyond the cretaceous. The age spreading rate and asymmetry at each grid node is determined by linear interpolation between adjacent seafloor isochrons in the direction of spreading.

Most new crus t forms at these mid ocean spreading ridges. The following features are shown at example depths to scale though each feature has a considerable range at which it may occur. Because of this correlation between age and subduction potential very little ocean floor is older than 125 million years and almost none of it is older than 200 million years.