What is responsible for the underwater waterfall illusion of Mauritius Island?

Question

From an aerial view just off the island of Mauritius, there is what appears be an underwater waterfall. The picture below illustrates this visual phenomenon:

The image can also be seen from the google maps satellite here.

What is responsible for this majestic illusion near the island? I have heard that it may be sand moving over the edge of an underwater cliff, and if so what causes the sand to be pushed off continuously without the process coming to a stop and what is responsible for this unique geographical landscape allowing this to occur?

Answer 1

The cause for this phenomenon is sand and silt moving down an underwater cliff as you guessed. The geography that makes this possible is as follows. The island of Mauritius is located on a giant plateau that was created by seafloor spreading a few million years ago. Most of which is under 8-150 meters of water. Where the waterfall effect occurs there is a huge drop-off which drops down thousands of meters. Because of the islands angle when the waves beat upon the shore and displace sand, the drawing out of the waves creates, you could say, a down pulling effect. This motion pulls the sand and silt down the drop-off, thus creating the underwater waterfall illusion. Because waves constantly bring sand and weathering and erosion keep making sand and silt, is not very probable that this illusion will stop for a long time, if it stop at all. I hope this was helpful.