Slime maybe behind some of the biggest tsunamis on record.
Yeah, that’s right. Not earthquakes, but slime. Although, actually, they sort of work the same way. Bear with me here.
Earlier this month, researchers published a report in the journal Geology showing how some of the most massive landslides on earth actually occur underwater. In some cases, these landslides can be 1,000 times more massive than, say, the landslide generated by something as massive above the sea surface like, oh, say, the eruption of Mt. St. Helens. Scientists have long wondered what caused these subsurface landslides, and now they think they know–a big layer of slime that the ocean floor slides around on.
The idea is that large hunks of the sea floor are actually resting on a layer of ooze made up of the remains of diatoms–tiny oceanic algae. As the diatoms die off over thousands of years, their microscopic corpses form a silica-rich slime. Clays that make up the sea bed build up over many, many years right on top of the silica slime. Gradually the pressure bearing down on the slime increases, squeezing water from the slime into the clay, which destabilizes the clay. At a certain tipping point–bang, the clay collapses, the seafloor shifts, and giant landslides ensue.
When that happens, just like it can above the sea surface, the huge energy released during a landslide can trigger a tsunami, even if the landslide happens at the bottom of the ocean. Scientists think that one such underwater slide 8,500 years ago off the coast of Norway sent waves 65-feet tall slamming into nearby coastlines. The team that put the study together thinks as many as 20 percent of all tsunamis might be because of these underwater slime slides. Figuring out where all this sea floor ooze is deposited may help predict submarine landslides and tsunamis in the future.
Slime-causes tsunamis. The more you know.