Name: 世界最古の難破船 (The Oldest Shipwreck in the World)
Uploaded: 2021-01-14T10:28:54.000Z
Duration: 10 min 52 s
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In 2017, scientists were scouting the floor of the Black Sea,

trying to study how sea levels had changed since ancient times.

But then, something unexpected suddenly appeared in the darkness: a ship.

An ancient ship, as a matter of fact, half-buried on the cold,

dark seafloor nearly two kilometers below the water's surface.

Upon further investigation, the team discovered that this 23-meter trading vessel

actually seemed to date all the way back to Ancient Greece,

That meant that they had accidentally found the world's oldest known intact shipwreck.

The scientists were able to crack this ship's secret

thanks to a combination of biology, engineering, and ocean sciences;

all of which are involved in a field called maritime or marine archeology.

there's a lot we can learn about how we study shipwrecks in general.

but not all shipwrecks are as beautifully-preserved as this one.

Even wrecks half as old are prone to serious damage and decay.

The problem is often the critters that live in the ocean.

Many types of organism like to burrow into or eat waterlogged wood,

including mollusks like shipworms and piddocks, and tiny crustaceans called gribbles.

Shipwrecks can also turn into impromptu reefs as corals

and other types of sea life grow on top of them.

And while that's very cute in an, “Aw, look they found a home!” sort of way,

This kind of life either hides wrecks, or breaks them down into a pile of mush.

This ancient ship managed to avoid that fate, though,

but not because there was anything special about Greek shipbuilding back then.

This boat just happened to sink in a very convenient location.

2 kilometers beneath the Black Sea, in the cold, lightless depths, there's very little oxygen.

It's what's known as an anoxic environment.

In this case, it happens because the Black Sea is really two separate layers of water:

a less salty one that generally comes from rain, rivers, or streams,

and a more salty one that comes in through a deep channel from the Mediterranean.

That extra-salty layer is more dense than the fresher stuff,

so it stays near the bottom of the sea and generally doesn't mix with the water above it.

And since oxygen gets absorbed from the atmosphere down, no mixing means no oxygen.

This makes it extremely hard for life to survive down there,

and that means ships rot much, much more slowly.

The Black Sea is actually home to all kinds of wrecks,

discovered about five dozen others on their expedition.

The researchers found it while prowling around the seafloor using an ROV,

Along with human-operated and autonomous versions,

vehicles like these are really your bread-and-butter

when it comes to exploring deep sea shipwrecks.

They typically look like a box covered in cameras with propellers,

and might come with extra features like robotic arms or scientific instruments.

They also come in all different sizes, where the largest ones can be the size of a truck.

As they descend, long cables connect the ROV to a human operator on the surface.

Then, the operator can send commands to the robot,

while the robot sends video and data to the operator.

Now, normally, expeditions don't just send ROVs to patrol the ocean and hunt for sunken ships.

Instead, they might use something like a magnetometer to scan huge areas

for promising metal objects, and then send an ROV to investigate.

This team just happened to skip that step

because they were already using an ROV for their other research.

In a lot of ways, they just got really lucky.

Still, even though finding this ship was straightforward,

studying it took more calculations and planning.

Since the boat was so deep, researchers couldn't just send a couple of scuba divers down there.

The world's deepest scuba dive only went down about 300 meters,

and deep dives can be dangerous because of water pressure.

So instead of sending down humans, the marine archeologists used their ROV.

And to really examine it, they used something called photogrammetry:

a way to measure and study objects by, essentially, taking their picture.

To do it, they used the camera and imaging device on the ROV to take a long series of snapshots.

Then, once they collected hundreds or even thousands of them,

they fed them into a computer, which built a highly detailed, composite 3-D portrait.

This portrait then let the team figure out things like the exact size and shape of the boat,

which is how they knew it was about twenty-three meters long.

It also allowed them to zoom in on specific features, like how the hull was put together.

That gave them more information about how it was constructed

and how well it might have performed in the open sea.

Photogrammetry is really helpful for record-keeping, too.

Like, in this case, the scientists decided to blow away some of the seafloor sediment

So now, if they want to know what things looked like beforehand, they have a detailed record.

Also, besides being useful for the scientists themselves, these 3-D models are cool

because they make it very easy to share exactly what an expedition is seeing.

Compared to using traditional diagrams, scientists can more easily publish papers,

invite analysis from other colleagues, or give the public insight into a hidden treasure.

They can even build virtual reality simulations.

Because looking at diagrams in a paper? That's cool.

But flying through a VR simulation of a spooky underwater shipwreck? That is awesome.

Of course, scientists don't just want to know how big a boat is, or what condition it's in.

They also want to know things like its age or where it came from.

Which is, you know, generally important in archeology.

To do that, researchers can look for certain artifacts or historic construction methods.

But when that kind of thing isn't available, or if they want more info,

they might also take small samples from the wreck itself.

For this Black Sea wreck, one of the ROVs took samples of the ship's wood for study.

That allowed them to figure out what species of wood the boat was made of, and it helped

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世界最古の難破船 (The Oldest Shipwreck in the World)

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