Magnetite Ocean Floor

This finding though unexpected was not entirely surprising because it was known that basalt the iron rich volcanic rock making up the ocean floor contains a strongly magnetic mineral magnetite and can locally distort compass readings.

Magnetite ocean floor.

The reason tiny grains of magnetite found within the volcanic basalt that make up the ocean floor behave like little magnets. This distortion was recognized by icelandic mariners as early as the late 18th century. These grains of magnetite can align themselves with orientation of the earth s magnetic field. More important because the presence of magnetite gives the basalt measurable magnetic properties these newly discovered magnetic variations provided another means to study the deep ocean floor the magnetite uralite and other minerals can be exposed by etching away the enclosing calcite with hydrochloric acid.

Magnetic striping of the sea floor after mid ocean ridges and trenches were discovered more evidence was discovered that helped to support the theory that the continents had moved around. Among the new findings was the discovery of zebra stripe like magnetic patterns for the rocks of the ocean floor. Magnetic striping magnetic minerals are found in rocks. Explains how magnetic polarity frozen into seafloor basalts reveals evidence for the creation of new seafloor at mid ocean ridges.