An iceberg may contain ice colored by thousands of years of dirt or even from a meteor strike.
A rare black iceberg found off the coast of Labrador has caused quite a stir
on social media after an angler living in Carbonear, New Mexico, photographed it while shrimping last month.
Hallur Antoniussen, a native of the Faroe Islands, was working with a crew aboard the factory freezer trawler Saputi off the coast of Labrador in mid-May. He had never seen icebergs like this one before.
"I've seen icebergs that were said to be rolling on the beach with rocks. This one is completely different. It's not just that he's all black. It's almost... diamond-shaped," Antoniussen tells CBC Radio's Labrador Morning program.
He spotted the iceberg by climbing on the ship's crane when they were more than 100 kilometers offshore in the Hopedale Channel between Nain and Hopedale. The day before, a crew member had counted 47 icebergs in the area.
Antoniussen doesn't think it's an iceberg that has tipped over or rolled ashore, picking up mud and rocks after grounding. He has seen many icebergs in his 50 years of fishing off the coast of Greenland, most recently off the coast of Labrador since 1989.
Photo: cbc.ca
The 64-year-old said it is difficult to estimate the size of the iceberg at sea, but he believes it is at least three times the size of an ordinary bungalow. He took the picture from a distance of about six kilometers. "It's not something you see very often, and a camera isn't something I run around with when I'm working. So I just grabbed my phone and took this picture," he says.
Antoniussen said the iceberg looked like a rock with many dark gray and black veins, and he quickly decided it was casting a shadow. The man took a picture to show it to other crew members of the fishing boat. Antoniussen then posted the photo on Facebook, and it soon garnered hundreds of comments.
Commenters speculated about everything from aliens to precious metals and even dinosaurs hidden in the ice. "It's an oil iceberg," one commenter wrote. "Looks like a giant woolly mammoth!" exclaimed another. Antoniessen clarified: this is an actual photograph.
Other people have wondered if the iceberg contains volcanic ash, the result of some ancient eruption.
An impressive iceberg
Lev Tarasov, a professor of physical oceanography at Memorial University, doesn't rule out the latter theory entirely.
Tarasov says there are volcanoes under the Icelandic ice caps, and he's not exactly sure about volcanoes in Greenland, but added that scientists have measured hot spots in the central part of the landmass.
Photo: cbc.ca
Like Antoniussen, he has never seen icebergs like this one. He said Tarasov had observed smaller versions of the black iceberg during field work in the Kangerlussuaq Fjord in Greenland last summer - just not as impressive.
In his opinion, the age of ice in the iceberg is at least a thousand years, but it can be exponentially - it was formed even 100 thousand years ago.
Tarasov says ice from all over Greenland slowly converges on its coastline, and when it reaches it, it breaks off to form icebergs. These icebergs can take one to three years before they reach the coasts of Newfoundland and Labrador.
Land travel
Tarasov says it's a reminder of how dynamic ice can be. Ice streams, also known as outlet glaciers, move much faster than other parts of the ice sheet; they carry ice from inland, passing through deep valleys or channels to the coast.
They pick up rocks and mud along the way. "There are patches of ice that travel up to 20 kilometers a year, which means that the the ice moves perhaps a few meters every hour," Tarasov said.
The bottom of the ice scrapes against the Earth's crust. This churning takes place, turning all these rocks and sediments into powder, which is then spread upward through the ice columns. According to Tarasov, it takes a long time for these pulverized rocks to spread so evenly across the ice.
Tip of the iceberg
Tarasov suggests that the black iceberg was probably part of a much larger chunk of ice before it broke off and fell into the water.
"Over time, as it moves around Baffin Bay and along the coast of Labrador, it melts. So I think most of that ice has melted. Maybe the part that's clear is underneath it, right? Again, 90 percent of the ice is underwater. So we're only seeing the tip of the iceberg," he said.
Tarasov believes that at some point the iceberg flipped over and is now showing its underside. He also offers another possible explanation for the intriguing color of the iceberg.
Photo: cbc.ca
He said there is strong evidence that an asteroid hit the northwest corner of Greenland about 12,000 years ago. There may be dust from this meteorite impact on the iceberg if it came from this area.
Be that as it may, the ice is likely not new: it's quite possible that the mud on the iceberg hasn't seen "the light of day for hundreds of thousands of years," Tarasov says.