Mavericks, Big Waves, and the Geography of Surfing

The underwater topography of Mavericks is what creates monster waves. The large reef known as “The Thumb” helps propel walls of water as high as 100 feet or more. Image courtesy The San Francisco Chronicle.

In 1994, legendary big wave surfer Mark Foo died while riding an 18-foot wave. The location was at Mavericks; and he will be remembered as the first and only surfer that Mavericks has claimed. Foo once said: “If you want the ultimate thrill, you must be willing to pay the ultimate price.”

Today’s Chronicle has a fascinating story on the waves themselves and what makes Mavericks such a big-wave factory. About halfway into the article is a harrowing tale of two rescue patrollers on a jet ski, who out-ran a deadly 100-foot wave in 2001, raced up the gigantic crest only moments before it could have killed them, and jumped over the top. Said rescuer Shawn Alladio:

“Normally, when you go over a big wave, you get pelted with the spray, like raindrops, on the other side,” Alladio said. “But these clots of water were huge, the size of your fist, and they exploded like you were getting pounded by water balloons. And on the wave fronts, each time we went up I could see all these fissures or ravines in the surface, and there was some kind of crazy light energy vibrating inside the wave like electricity, and I remember thinking, ‘Those are the fingers of God.'”

Obviously the physical crests and ridges, particularly the reef with the moniker, “The Thumb” is what creates the waves, but what created the ridges? We have to look back as far as the Miocene to Pliocene age, when sediments of mussels and other such crustaceans formed a hard, erosion resistant body of rock known as the Purisima Formation. Top it all off with the Seal Rock fault line, and you’ve got unique wave geography — so unique, that only three places in the world can claim 100-foot kahunas.

All of this is compounded with drop in depth from about 18 feet at “Mavericks” to well over 70 feet as you get less than 1/4 of a mile out, and you have the power of thousands of miles concentrated into some awesome, surely tubular — in all senses of the word — waves.