On December 19, fishermen working off the west coast of Yemen reported a 30-meter (90-ft.) fountain of lava bursting forth from the Red Sea, amid a group of small islands known as the Zubair Group.
Over the course of three days, NASA satellites detected the ash plume and increased levels of sulfur dioxide. But on December 23, high-resolution images revealed that more than an eruption had taken place — an island had been born.
Location of the newly formed island in the Red Sea.
White arrows show how the directions of plate movement are creating the Red Sea as they separate. Source: USGS
The new island and those surrounding it are located along a divergent plate boundary known as the Red Sea Rift. Once linked as a single continent, Africa and the Arabian peninsula are now moving apart, creating and enlarging the Red Sea in the process.
The cause of the tectonic plates movement appears to lie deep within the Earth’s interior, where temperature instabilities between the core and mantle cause magma to flow upward, forming a convection-driven conveyor belt that weakens the plate above by pulling it downward.
As the plate weakens and cracks, the separated pieces move in different directions, and molten rock from below fills in the cracks. Where such spreading or mid-ocean ridges are found, rift valleys and chains of islands form, further driving the plates apart.
