Magnetic Stripes On The Sea Floor Are Created Where

In the 1960s the past record of geomagnetic reversals of earth s magnetic field was noticed by observing magnetic stripe anomalies on the ocean floor.

Magnetic stripes on the sea floor are created where. These patterns were unlike any seen for continental rocks. What they discovered was that the magnetism of the ocean floor around mid ocean ridges was divided into matching stripes on either side of the. Magnetic stripes and isotopic clocks oceanographic exploration in the 1950s led to a much better understanding of the ocean floor. Plate tectonics and reversals of the earth s magnetic field are responsible for the magnetic stripes found on the ocean floor.

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. Magnetic reversals found in the sea floor do not cause continental drift. The patterns reflect the creation and spreading of oceanic crust along the mid oceanic ridges. It does however provide evidence that sea floor spreading occurs and hence is evidence for the theory of plate tectonics.

These surveys revealed a series of invisible magnetic stripes of normal and reversed polarity in the sea floor like that shown in the figure below. Basalt forming at the ridge crest picks up the existing magnetic polarity.