Seafloor Spreading and Marine Magnetic Anomalies,
     six animations

This is a set of movies designed to elucidate the Vine-Matthews Hypothesis for the formation of marine magnetic anomalies. Magnetic stripes are observed over most of the world's ocean floors. This explanation for their creation was one of the most powerful drivers of the 1960's plate tectonics revolution that profoundly changed our understanding of Earth processes and history.

In these movies, sea floor spreading is depicted on three spreading centers connected by transform faults, with a front-cut cross section.  The first five animations demonstrate spreading, transform faulting, magnetic polarity reversals, and the formation of seafloor magnetic stripes.  A sixth animation shows the formation of magnetic stripes without the timescale overlay, in case you find that useful.   These conceptual presentations are shown occurring at a gently rifted spreading center (i.e., a slow-medium rate spreading center).

Note: an earlier version had a mistake in the reversal time scale.  The latest versions date from September 2009.  If you have some that are older, please replace them with these. 

Download Seafloor Spreading Package of 6 movies

Download: SFS package (61 MB)

Download individual Seafloor Spreading animations:

To view these movies, click on their images.

SFS animation (15 MB)

SFS with spreading arrows (15 MB)

SFS with transform fault arrows (15 MB)

Magnetic polarity reversal explanation (5 MB)

Download: SFS with
magnetic stripes and reversal scale (15 MB)

SFS with magnetic stripes (15 MB)

Made by Tanya Atwater using Photoshop, Morph and Final Cut Pro with useful comments from Ken MacDonald and Doug Burbank.

Comments on this and all of the materials offered on this site are welcomed: