This incredible drone footage captures the scale of growth in a huge crack which is threatening to tear Africa in two.

The enormous crevice is already several miles long and now measures 50ft deep and 20 metres wide.

Appearing in Kenya, the crack has also led to potentially destructive seismic activity and caused part of the Nairobi-Narok highway in in south-western Kenya to collapse.

Drone footage shows cars and people walking near the sunken earth, dwarfed by its sheer size.

Experts have predicted the crack will continue to grow over millions of years, allowing ocean water to flood in.

The enormous crack continues to widen (
Image:
DailyNation /Youtube)
A large part of a motorway intersection has been destroyed (
Image:
DailyNation /Youtube)

This could result in parts of Ethiopia, Somalia and the Horn of Africa to become and island after being ripped from the mainland.

Dr Lucia Perez Diaz, a postdoctoral researcher at the Fault Dynamics Research Group, at Royal Holloway, University of London, has written an article for the Conversation explaining how Africa will split apart.

She said tectonic plates in the Earth's crust and upper mantle can create a rift when they rupture, and an active example is the East African Rift Valley where the crack has appeared.

Ms Perez Diaz wrote: “The East African Rift Valley stretches over 3,000km [1,800 miles] from the Gulf of Aden in the north towards Zimbabwe in the south, splitting the African plate into two unequal parts: the Somali and Nubian plates.

“Activity along the eastern branch of the rift valley, running along Ethiopia, Kenya and Tanzania, became evident when the large crack suddenly appeared in south-western Kenya.”

Shocked onlookers peer into the opening (
Image:
DailyNation /Youtube)
The crack runs for several miles though the valley (
Image:
DailyNation /Youtube)
Parts of Ethiopia and Somalia will become an island

Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin, she added.

The scenario played out when a huge land mass broke in two, creating what's now known as South America and Africa around 138 million years ago.

The process called continental rifting involves a large "magma plume" which forces the Earth's crust upwards, causing it to weaken and break apart.

Researchers have found evidence of a hotter-than-normal plume - called the "African Superswell" - in the rift valley.

The crack is growing at a rate of just millimetres per year
Dr Lucia Perez Diaz explained how Africa will split in two

The rift that has appeared in Kenya is spreading at just a few millimetres per year.

Dr Perez Diaz wrote: "Eventually, over a period of tens of millions of years, seafloor spreading will progress along the entire length of the rift.

"The ocean will flood in and, as a result, the African continent will become smaller and there will be a large island in the Indian Ocean composed of parts of Ethiopia and Somalia, including the Horn of Africa."

She added: "Dramatic events, such as sudden motorway-splitting faults or large catastrophic earthquakes may give continental rifting a sense of urgency but, most of the time, it goes about splitting Africa without anybody even noticing."