Earth’s crust stretches just like pizza dough

New Scientist

Image: VancityAllie

You know how if you stretch pizza dough sometimes it will break right away and sometimes it will stretch and stretch? That, it turns out, is how the Gulf of California was formed.

A series of seismic surveys across the 1200-kilometre-long gulf, which is formed by a young tectonic rift extending northward into California along the San Andreas fault, show that the nature of the rift varies. In some regions it is wide: this is where the continental crust stretched some 350 kilometres before it finally broke and allowed oceanic crust to form. In neighbouring regions, the continental crust stretched only 70 kilometres before breaking (Nature, DOI: 10.1038/nature06035).

“We see variation on a length scale we weren’t expecting,” says Gary Axen of the New Mexico Institute of Mining and Technology, Socorro, and a member of the survey team. Read more on newscientist.com…