Magnetic Minerals On The Ocean Floor

They record the strength of the magnetic field in rocks on the ocean floor.

Magnetic minerals on the ocean floor.

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. The figure below includes two images of the ocean floor. 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. As lava cools the minerals settle parallel to the earth s magnetic field.

Plate tectonics and reversals of the earth s magnetic field are responsible for the magnetic stripes found on the ocean floor. Basalt is one of these rocks. These minerals provide a record of the direction of earth s magnetic field at the time when the molten matter that formed the rock. These two things were the magnetic striping on the ocean floor and the age of seafloor rocks.

Scientists can use this data to make magnetic maps of the ocean floor. Plate tectonics explains patterns observed in data from these studies. It is found in lava. When the earth s magnetic field reverses a new stripe with the new polarity begins.

Some igneous rocks contain minerals that are magnetic. Magnetic striping magnetic minerals are found in rocks. Evidence for seafloor spreading. Throughout earth s history.

3 rocks containing iron give us a record of earth s magnetic field.