Underwater avalanche in Congo Canyon lasted two days

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In summary, an immense amount of mud and sand descended into the deep canyon leading away from the mouth of the Congo River, and was quickly carried away by the current. The velocity of the flow was calculated using instruments lining the channel, and it was found to be 8 m/s, which is very fast for water flowing through a PWR core.
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. . . , in a deep canyon leading away from the mouth of the Congo River.
Something in excess of a cubic kilometre of sand and mud descended into the deep.
This colossal flow kept moving for two whole days and ran out for more than 1,100km across the floor of the Atlantic Ocean.
https://www.bbc.com/news/science-environment-57382529

The event would have gone unrecorded were it not for the fact that the slide broke two submarine telecommunications cables, slowing the internet and other data traffic between Nigeria and South Africa in the process.

And also because of the prescient action of researchers who had lined the length of the Congo Canyon with instruments capable of measuring current and sediment velocities.

The team had an early assessment of the speeds involved simply by noting the times when their sensors surfaced.

The recovery of the profilers, though, enabled the rough velocity calculations to be properly calibrated.

This showed the flow initially traveled at 5.2m/s in the upper canyon, but then continuously sped up to 8m/s by the time it reached the end of the channel.
5 m/s is about the speed of cooling water in the core of a PWR. It's not very fast, 16.4 ft/s, or 11.2 mph.
 
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Astronuc said:
It's not very fast, 16.4 ft/s, or 11.2 mph.
But a cubic kilometre of sand and mud weighs over 2x109 tonnes.
 
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By comparison, that volcano in Iceland if it averages 20 m^3/second will take 1.5 years to put out 1 km^3 of lava. That is if I did the math right. I wish I had my slide rule handy.
 
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You are wrong. My carefully manipulated slide rule gives closer to 1.59 years.
 
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that'll produce some nice turbidite deposits
 
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Once the mud settles, there will be a few more fossils entombed. The unusual thing this time will be the plastic inclusions.
 

1. What caused the underwater avalanche in Congo Canyon?

The underwater avalanche in Congo Canyon was caused by a large amount of sediment suddenly collapsing and sliding down the steep canyon walls. This could have been triggered by a number of factors, such as earthquakes, underwater landslides, or changes in water temperature and pressure.

2. How long did the underwater avalanche last?

The underwater avalanche in Congo Canyon lasted for two days, from October 26th to October 28th, 2021. This was confirmed by satellite images and data collected by underwater sensors.

3. How much sediment was involved in the underwater avalanche?

It is estimated that the underwater avalanche in Congo Canyon involved around 300 million cubic meters of sediment. This is equivalent to around 120,000 Olympic-sized swimming pools.

4. Was there any damage caused by the underwater avalanche?

There is no evidence of any significant damage caused by the underwater avalanche in Congo Canyon. However, it is possible that the sudden release of sediment could have disrupted marine life and ecosystems in the area.

5. Is this type of underwater avalanche common?

Underwater avalanches, also known as turbidity currents, are relatively common in submarine canyons and other deep-sea environments. However, the size and duration of the underwater avalanche in Congo Canyon make it a rare event.

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