Geophysicists can read these patterns from the magnetic anomalies they measure with a magnetometer.
Sea floor magnetic pattern.
Basalt the once molten rock that makes up most new oceanic crust is a fairly magnetic substance and scientists began using magnetometers to measure the magnetism of the ocean floor in the 1950s what they discovered was that the magnetism of the ocean floor around.
Such magnetic patterns led to recognition of the occurrence of sea floor spreading and they remain some of the strongest evidence for the theory of plate tectonics.
These patterns of stripes provide the history of seafloor spreading.
As long as the magnetic field remains constant the polarity stripe widens.
Plate tectonics plate tectonics seafloor spreading.
As upwelling of magma continues the plates continue to diverge a process known as seafloor spreading.
These age data also allow the rate of seafloor spreading to be.
At slow spreading ridges the anomalies are squeezed tighter together but the basic.
Samples collected from the ocean floor show that the age of oceanic crust increases with distance from the spreading centre important evidence in favour of this process.
Magnetic evidence for seafloor spreading explains how magnetic polarity frozen into seafloor basalts reveals evidence for the creation of new seafloor at mid ocean ridges.
Where the magnetic wiggles or anomalies are broader the spreading rate has been faster.