A New Land Is Born
At the northern edge of Zubair Islands - between Eritrea and Yemen in the Red Sea, a new island has just been minted!
Yet to be named, this island measures 1700 ft by 2300 ft – an area of about 75 acres! It is a mere mound of lava and ash, piled up with the eruption of an undersea shield volcano in the Red Sea.
So, how does this all happen?
Creation of new lands
According to the tectonic plate theory, the earth is made up plates that move around like jigsaw puzzle pieces. The floating segments meet each other at plate boundaries. Occasionally, volcano or lava flow occurs when molten lava comes to the earth’s surface at plate boundaries. Sometimes though, hotspots occur in the middle of plates that can cause a plume of hot mantle material to come to surface. These fissures may persist and with plate movements, they can form a chain of volcanoes over millions of years.
What makes new island creations rare and exciting is that, when lava emerges under the ocean, it immediately cools and forms a crust – “pillow lava”. Oceanic activity usually erodes away the crust leaving nothing much by way of land. It is only when the persistent volcanic activity and buildup is faster than the force of erosion, do the islands actually get created and survive.
There are a few important islands that are of fairly recent origin. Surtsey, off the coast of Iceland - formed through 4 years of volcanic activity in 1963. Anak Krakatau, in the caldera of Krakatoa in Indonesia, rose from the water in August 1930. More recently in the Canary Islands region, lava flow is causing a new island to be formed off the northwest coast of Africa.
The Hawaiian Islands
The most well known island chain that have been created as a result of volcanic activity are the Hawaiian islands. These islands are formed from underground volcanoes that have reached the surface of the ocean. What gives the Hawaiian islands its distinct shape? Geophysicists have an explanation.
Under the present day Big Island lies a giant hotspot that releases hot magma from within the Earth. The hotspot does not move, but the Pacific plate (on which the islands rest) is moving ever so slightly in the north-west direction. The continually moving plate eventually carries the island beyond the hotspot, cutting it off from the magma source. As one island moves away, the next one develops over the hotspot and the cycle is repeated. For a pictorial description of the Hawaiian island formation, check out this wonderful resource.
Even more amazing is that the Hawaiian Islands have an unborn sister! Christened Loihi, on the south east end of Big Island is a volcanic hotspot. Presently 3000 ft below the sea level, the island began forming some 400,000 years ago. The new land is expected to emerge from the ocean in about 10,000 to 100,000 years or so, as more lava build up takes place.