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Diving Archaeologists Explore a Sunken Shipwreck

Scuba diving scientists today explored the remains of a ship that sank in 1914, but they weren't looking for buried treasures — at least not the kind that pirates in movies search for. They were in search of something far more valuable to archeologists — historical treasures.

Marine archaeologists swam in and around and photographed the wooden freighter Montana at the National Oceanic and Atmospheric Administration's (NOAA) Thunder Bay National Marine Sanctuary and broadcasted their efforts in three live webcasts.

The Montana is one of more than 200 well-preserved submerged historic sites in "Shipwreck Alley," an area of northern Lake Huron known for extreme weather  and dangerous shoals. The freighter was built in 1872 and burned and sank on Sept. 6, 1914; however, the cause of the fire is unknown.

The shipwreck  has been frozen in time since it hit the bottom. The remains are like a museum on the bottom of the lake, said maritime archeologist Cathy Green of NOAA.

"Today, it's sitting like it would have been over a century ago," Green said.

The ship burned to the water line, so the lower half of the ship is all that remains. The ship's bow section is broken off and the hull is now on its side. The scuba divers were able to point out the ship's boiler and propeller. Also visible was a giant steel arch that supported the long wooden hull. The remains of the ship sit mostly about 70 to 75 feet (21 to 23 meters) under the water's surface .

Great day for a dive

Today was a great day for diving, the NOAA scientists said. The water was 60 degrees Fahrenheit (16 degrees Celsius) and visibility was 30 feet (9 m). The divers were submerged for up to 40 minutes at a time.

Their dives were broadcast on the Internet live at 10 a.m., 12:30 p.m., and 3 p.m. EST at Immersionlearning.org.

With a simple tape measure and a special waterproof tablet for taking notes underwater, the scientists — wearing 200 pounds (90 kilograms) of scuba gear — documented the shipwreck. They also snapped photos so they can piece together a photomosaic of the remains.

Mussel invasion

While underwater, the researchers also made observations about the health of the Great Lakes, such as the spread of invasive species. The divers saw firsthand how one well-known invasive species  — zebra mussels — have spread across the region.

"The mussels cover just about every surface of the shipwrecks in Thunder Bay," said maritime archeologist Russ Green of NOAA. Green was one of the scuba divers that answered questions while underwater during the live webcast.

"It's very dramatic, it complicates archeology, but the real story is what [the invaders have] done to the fish stocks in the Great Lakes," he said. "They filter out food that the smallest fish in the Great Lakes need to survive."

Explore for yourself

The Thunder Bay National Marine Sanctuary encompasses 448 square miles (1,160 square kilometers) of northwest Lake Huron, off the northeast coast of Michigan's Lower Peninsula. It is the thirteenth national marine sanctuary in a system that extends from American Samoa to Massachusetts.

The sanctuary was established to protect a nationally significant collection of over 100 shipwrecks, spanning over a century of Great Lakes shipping history.

Anyone certified as a scuba diver can explore the shipwrecks and people that aren't scuba-savy can snorkel or kayak in Thunder Bay.

"We want to keep everything intact so that future divers can explore it," Cathy Green said. "Just because something is a marine sanctuary doesn’t mean you should stay out. It's like we say, 'Take only pictures, leave only bubbles.'"

This article was provided by OurAmazingPlanet, a sister site to LiveScience

Brett Israel was a staff writer for Live Science with a focus on environmental issues. He holds a bachelor’s degree in biochemistry and molecular biology from The University of Georgia, a master’s degree in journalism from New York University, and has studied doctorate-level biochemistry at Emory University.