http://en.wikipedia.org/wiki/Mid-Atlant ... h_to_South
Geology of Mid-Atlantic Ridge
These mountain ranges are tectonic plates which move apart along a divergent boundary as magma rises from the Earth's mantle. Heat from the magma causes the crust on either side of the rifts to expand, forming the ridges.
The ridge actually sits on top of the mid-Atlantic rise which is a progressive bulge that also runs the length of the Atlantic Ocean with the ridge resting on the highest point of this linear bulge. This bulge is thought to be caused by upward convective forces in the asthenosphere pushing the oceanic crust and lithosphere.
This divergent boundary first formed in the Triassic period when a series of three-armed grabens coalesced on the supercontinent Pangaea to form the Ridge. Usually only two arms of any given three-armed graben become part of a divergent plate boundary. The failed arms are called aulacogens and the aulacogens of the Mid-Atlantic Ridge eventually became many of the large river valleys seen along the Americas, and Africa (including the Mississippi River, Amazon River and Niger River).
The ridge is about 2,500 meters below sea level, while its flank is about 5,000 meters deeper.
Islands on the Mid-Atlantic Ridge, from North to South
The islands are, from North to South , with their respective highest peaks, elevations in m, and location:
Northern Hemisphere (North Atlantic Ridge):
Jan Mayen (Beerenberg, 2277 m, at 71°06'N, 08°12'W), in the Arctic Ocean
Iceland (Hvannadalshnúkur in the Vatnajökull, 2109.6 m, at 64°01'N, 16°41'W), which the ridge runs through
Azores (Ponta do Pico or Pico Alto, on Pico Island, 2351 m, at 38°28′0″N, 28°24′0″W)
Bermuda (Town Hill, on Main Island, 76 m, at 32°18′N, 64°47′W) (Bermuda was formed on the ridge, but is now considerably west of it)
Saint Peter and Paul Rocks (Southwest Rock, 22.5 m, at 00°55′08″N, 29°20′35″W)
Southern Hemisphere (South Atlantic Ridge):
Ascension Island (The Peak, Green Mountain, 859 m, at 07°59'S, 14°25'W)
Tristan da Cunha (Queen Mary's Peak, 2062 m, at 37°05'S, 12°17'W)
Gough Island (Edinburgh Peak, 909 m, at 40°20'S, 10°00'W)
Bouvet Island (Olavtoppen, 780 m, at 54°24'S, 03°21'E)
So my thoughts are .. that at one time, there existed more lands mass around these islands which are presently existing. Maybe not such a large
mass of land as seen in this picture that you just posted, but still more
land above the water line, along the mid-atlantic ridge. Probably more so at the northern end of the North Mid-Atlantic Ridge. These could have easily been stop points or jumbing off points for early sea travelers in the Atlantic between Europe and North America. Maybe even Atlantis existed along one of these islands near the south end of the Northern Mid-Atlantic Ridge.
The same thing has been pointed out for the southern Pacific around Eastern Island. Not exactly like the Mid-Atlantic Ridge, but islands now submerged. At one time numerous islands where above water in the Pleistocene that could have been used as hopping points across the Pacific with the help of the currents. This helped to break up long distance sea voyages. And we have currents that would have easily moved sea travelers back and forth across the Atlantic also.
And I read in that previous article that sand was found that appeared to be beach sand, sand worn by apprasive water action that could only have occured near the water surface. Not sure where this sample came from that they referred to as "beach sand" thou. Have to go back and reread the article.
As far as subs, I do expect that they take the under water mountain chain of the Mid-Atlantic very seriously.
