Britannica Sources used in this answer

What did the Vine-Matthews hypothesis explain about magnetic stripes on the seafloor?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Earth's lithosphere and upper mantle — oceanic crust A cross section of Earth's outer layers, from the crust through the lower mantle.

The Vine-Matthews hypothesis explains that the linear magnetic stripes observed on the seafloor are a record of Earth’s magnetic field reversals captured by the oceanic crust as it forms at spreading centres.12

The hypothesis relies on three fundamental principles:
* Geomagnetic Reversals: Earth’s magnetic field periodically reverses its polarity.2
* Seafloor Spreading: New crust is continuously created at oceanic ridges and moves outward.23
* Permanent Magnetization: As magma cools and solidifies into basalt, iron-titanium minerals lock in the orientation of the magnetic field at that time.12

When the field is in a "normal" state, the crust creates a positive magnetic anomaly; during a reversal, it creates a negative anomaly. As the crust splits and moves away from the ridge, these magnetized blocks form a symmetrical, mirror-image pattern on either side of the ridge axis. By correlating these stripes with known reversal timescales, scientists can determine the age of the seafloor and calculate the rate of seafloor spreading.123