The two mysterious flower-like shapes scientists recently discovered off the Gulf of Mexico turned out to be forms left by an asphalt volcano.

The smooth black rocks that resemble massive flowers confirm that an asphalt ecosystem of volcanoes stretches across the Gulf, the Daily Mail reported.

"Within a few minutes, the scientists on the dive realized that they were looking at a much unexpected example of an asphalt volcano," said the NOAA, as quoted by the Daily Mail.

A team of archeologists, marine biologists and other researchers have been excavating the sites of three shipwrecks that rest under about a mile of seawater 175 miles from the Texas coastline. The explorers have also found anchors, dishes, a cannon and a clock, but the giant asphalt forms were probably the biggest surprise.

"Imagine that this would be like a big piece of molten tar," William Kiene, a regional scientist with NOAA's Office of National Marine Sanctuaries, described the hardened eruptions to KHOU. "And as it gets to the surface and it comes in contact with the cold water, it would solidify. So it came up in this very peculiar shape, like a lily. When we see something like that, we just blurt out these odd names. So we come up with this: 'Tar Lily.'"

Researchers aren't sure what caused the ships to sink. One theory is that the largest vessel was a privateer, a government-authorized ship that plundered foreign competitors. Of the two smaller vessels, one appeared to have transported hides and tallow, while the other has no evidence of cargo. The team has hypothesized that it may have carried animals or even slaves.

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