Magnetic Reversals On The Ocean Floor

Most dry land has a modest elevation above sea level while most of the ocean floor is about 3 kilometers or 2 miles lower down.

Magnetic reversals on the ocean floor.

Magnetic reversals moving continents 16. How magnetic reversals on the seafloor provide evidence for seafloor spreading. In the 1950s ocean going research vessels recorded puzzling data based on the magnetism of the ocean floor. It was determined that the rock of the ocean floor had bands of embedded iron oxides that alternately pointed toward geographic north and geographic south.

This indicates how strong in your memory this concept is. When magma flows out of a mid ocean ridge small magnetic minerals in the magma align themselves to point in the direction of the earth s current magnetic north. Past field reversals can be and have been recorded in the frozen ferromagnetic or more accurately ferrimagnetic minerals of consolidated sedimentary deposits or cooled volcanic flows on land. It is known that leading up to a magnetic reversal the strength of the field.

Where the ocean is about 1 kilometer deep is much less. The area of in between depths e g. The past record of geomagnetic reversals was first noticed by observing the magnetic stripe anomalies on the ocean floor.