The detail is jaw-dropping. Photo / National Geographic
From lost cities to shipwrecks, some of the world's most intriguing secrets lay in our oceans. And now, some of these fascinating sites — including one that lies in Australia's backyard — is set to be explored in unprecedented detail for the new National Geographic series 'Drain The Oceans'.
A team of experts used groundbreaking technology and the latest scientific data from underwater systems, combined with expert opinions and digital recreations, to analyse the ocean riddles that have mystified generations.
Sites across the world were explored including the China Seas, Gulf of Mexico, Mediterranean, Nile, Pacific Rim, Atlantic Ocean and Baltic Sea. Closer to home, they ventured to the Indian Ocean off the coast of Western Australia to find two shipwrecks.
Andrew Ogilvie, CEO and executive producer at Electric Pictures, which co-produced the 10-part series that starts tonight on Sky's National Geographic channel, told news.com.au the footage from the quest for answers is like nothing ever seen before.
"For the first time we are able to see what these places look like on a grand scale and with clarity that is simply not possible using traditional underwater photography," Mr Ogilvie said.
"Drain The Oceans uses a range of data — from bathymetric sonar scans to video footage and photogrammetry — with sophisticated computer generated graphics to create highly accurate three-dimensional models of the bottom of our oceans, lakes and rivers.
"This process allows the filmmakers to recreate natural wonders, shipwrecks, ancient ruins and other human artefacts that can be found on the sea floor — revealing them in unprecedented detail, as if they were on dry land."
The filmmakers use the same technique to explain how underwater earthquakes, volcanic eruptions and giant tsunamis threaten hundreds of millions of people living around the Pacific Ocean. As well as revealing how it is believed the impact of a huge meteor in the Gulf of Mexico wiped out the dinosaurs.
They also probe the network of underwater cables in Asia that are vital to the operation of the internet, explore the remains of ancient drowned cities in the Mediterranean and uncover the lost wonders of ancient Egypt.
Here are three of the most intriguing shipwrecks featured in the series.
It was the bloodiest scene in Australia's naval history. The battle between the Australian ship HMAS Sydney and German cruiser Kormoran occurred in November 19, 1941 off the coast of Western Australia.
Both ships were destroyed. There were no survivors on the 645-strong Sydney, but 317 of the Kormoran's crew were rescued.
Much controversy surrounded the battle, which remains one of Australia's greatest wartime mysteries. Many wondered how a purpose-built warship such as the Sydney could be defeated by the modified merchant vessel the Kormoran. Why had it been a sitting duck for the raider?
Inquiries were launched, numerous books penned, and speculation spread was rife. Some even asked, was it a cover-up?
With the locations of the wrecks unverified for decades, David Mearns, one of the world's best wreck hunters, began studying the battle in 2001. By 2008, he joined forces with the Australian Government to track them down, and the National Geographic series follows the moment he found both ships.
Equipped with new scanning technology, he was able to explore the battered ship and provide evidence of the brutal conflict that led to both settling in an underwater grave.
"The atmosphere was very tense, very pressured," Mr Mearns says of the expedition in preview footage of the show.
"I had to locate not just one ship but two ships."
However, the Kormoran captain had left vital clues of where the ship went down, helping Mr Mearns to track it. After hunting for 12 days, he spotted the shadow of the vessel 200 kilometres off the coast — he had found it. Four days later, he located the Sydney.
"It came up on the screen suddenly," he said. "It was just total elation that we found it."
At a depth of over two kilometres, it was too far to dive so they sent a remotely operated vehicle (ROV) down to explore the wreck. Among the ruins of a savage fight to the death were scattered shoes, a chilling reminder that it's a mass grave.
As there's only so much detail that an underwater ROV camera can provide, the team used scan data with computer generated imagery to "drain" the Indian Ocean and reveal new details the ship. This made the "pride of the nation" visible for the first time in over 70 years.
What they discovered was a ship was puck-marked by battle damage, evidence of a fight close-up. Using evidence from the seabed, they were able to recreate the battle between the two lost ships and show a Nazi secret weapon in action.
Little is known about the Monterrey shipwreck, which lies on the sea floor off the Gulf of Mexico at an approximate depth of 1.3km.
This makes it difficult to get to, but it also means it's well-preserved due to the cool temperature down at that level. So the experts launched a ROV down to the seabed, four hours later it began sending back tantalising glimpses of the ship and its contents.
Dr. Frederick Hanselmann, underwater archaeologist at the University of Miami told the National Geographic: "We are astounded, we are excited because what we're looking at is a largely intact ship almost a mile deep in the Gulf of Mexico and it was just mind-blowing."
Next, they "drained" the water from the ship, in the hopes of discovering what it was doing, how it came to lie on the seabed, and the biggest mystery of all — who was on-board?
They discovered that the bow is still intact, anchor still stowed, and steel plates and muskets remain visible. And that's just the tip of the iceberg.
While conducting an oil pipeline survey using an ROV, marine archaeologist Rob Church came across a wreck.
"To see a boat like the Robert E Lee, which is really a beautiful wreck site, it's really incredible," Mr Church said.
The ROV collected data before the team "drained" the ocean, revealing extraordinary detail and providing new evidence about her final moments.
They discovered that the ship's bridge had disappeared, unable to withstand the forces of drag as the ship plummeted through the water. They could see the deck gun on the stern still in the store position, indicating the attack was sudden and unexpected.
Lying next to the wreck was two lifeboats, showing there was no time to deploy them. In fact, experts believe it took just three minutes for it to sink, on that terrible day some 76 years ago.
Drain The Oceans, starts tonight at 8.30pm on Sky's National Geographic channel.
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