What kinds of features would you expect to see at the edges of two plates, like these that are moving apart at their boundary?

Along these boundaries you will, lava spewing from long fissures and geysers spurting superheated water, have frequent earthquakes strike along the rift.

places of higher salinity. there are parts of the ocean where hardly any rain falls but warm dry winds cause lots of evaporation. this evaporation removes water – when water vapour rises into the atmosphere, it leaves the salt behind, so the salinity of the seawater increases. this causes the seawater to become denser.