Tom Dettweiler makes his living miles down. He helped find the Titanic. After that, his teams located a lost submarine heavy with gold. In all, he has cast light on dozens of vanished ships.

Mr. Dettweiler has now turned from recovering lost treasures to prospecting for natural ones that litter the seabed: craggy deposits rich in gold and silver, copper and cobalt, lead and zinc. A new understanding of marine geology has led to the discovery of hundreds of these unexpected ore bodies, known as massive sulfides because of their sulfurous nature.

These finds are fueling a gold rush as nations, companies and entrepreneurs race to stake claims to the sulfide-rich areas, which dot the volcanic springs of the frigid seabed. The prospectors - motivated by dwindling resources on land as well as record prices for gold and other metals - are busy hauling up samples and assessing deposits valued at trillions of dollars.
"We've had extreme success," Mr. Dettweiler said in a recent interview about the deepwater efforts of his company, Odyssey Marine Exploration of Tampa, Fla.

Skeptics once likened mining the deep to looking for riches on the moon. No more. Progress in marine geology, predictions of metal shortages in the decades ahead and improving access to the abyss are combining to make it real.

And:

Fifteen years ago, would-be underwater miners staked the world's first claim: Nautilus Minerals won title to about 2,000 square miles of the Papua New Guinea seabed rich in volcanic features. The company, based in Toronto, inched toward mining but quickly expanded its prospecting to hundreds of Pacific sites and has since identified dozens of areas as potential candidates for seabed mining.

Last year, Nautilus won a 20-year lease to mine a rich deposit in the Bismarck Sea, in the southwestern Pacific. The mounds are a mile down. The company says the site holds about 10 tons of gold and 125,000 tons of copper.

Nautilus plans to start mining next year but also cites possible delays. It is building robots up to 25 feet tall that are to collect sulfides and pump them to the surface. Barges are then to carry the seabed minerals to Rabaul, a Papua New Guinea port some 30 miles away.

"We're making good progress," Stephen Rogers, the company's chief executive, recently told analysts.

David Fuller's view This is interesting, albeit highly speculative at this stage. Nevertheless, vast reserves of shale oil and gas were known to exist in the USA decades before the fracking technique was invented, making extraction possible. They are now a vital resource, increasing energy independence for the USA and no doubt many other countries over the next few decades.

The sulphurous mounds described above and their mineral content are less crucial to our long-term prosperity, but presumably more accessible although the technology for extracting them still needs to be perfected. There will also be many environmental and regulatory hurdles to contend with.

Judging from the Nautilus share performance (weekly & daily) (shown in CAD and the share is also listed in the USA and UK), the challenges remain considerable for this company which has yet to make a profit. Nevertheless, we should keep an eye on this fledgling deepwater mining industry as it should eventually provide opportunities for investors.