Who is Jose San Martin?

José Francisco de San Martín (February 25, 1778–August 17, 1850) was an Argentine general and governor who led his nation during the wars of Independence from Spain.

a mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. this uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.a geomagnetic reversal is a change in a planet's magnetic field such that the positions of magnetic north and magnetic south are interchanged.