Looking for a nice spot to do some deep diving? Not too touristy? Well, here’s the place. Last night at around 2am (I admit I was off-shift and sleeping) we came across a spectacular feature of the Indian Ocean’s topography: a seamount. The average water depth in the area here between Madagascar and La Réunion is about 5000m. Within a few miles this seabottom topography rises to only about 50m water depth! Picture something like Mt. Blanc under the water surface and you are not far off! It s about the same dimension.
Seamounts are a fascinating feature of our planet! They are mostly extinct volcanos that were eroded by the sea and no longer appear as islands. There is an estimated 100.000 (!) seamounts under the oceans and many of them wait to be explored. The one we moved over last night is known from satellite based seafloor topography estimates (so, ok we did not really “discover” it) but we are the first to map it precisely with sonar depth mapping techniques.
This mapping technique sends sonar signals into the water and produces images just like the ones we know from medical imaging. Yes, and sometimes people come into the monitoring room, look at the screen and say “oh, look it’s a boy!”.
Yann, our experienced diver tells us that 50m depth is something that still can be reached by scuba-diving. It is likely to be an extremely rich and interesting environment from a biological point of view similar to corral reefs. So consider this for your next diving vacation. But beware the next bar is about 500km away!