Kenya is slowly splitting at the Rift Valley, geologists have said after massive Earth movements on Monday morning left deep fissures in Narok County.
At the intersection of the damage with the busy Mai Mahiu-Narok road, what was recently an even plain of fertile, arable land has been reduced to a rugged expanse, with a huge tear that is as much as 50 feet deep and more than 20 metres wide running through it.
This spot, however, is just one of the tens, perhaps hundreds, of other weak spots on the Great Rift Valley, which runs through the continent from the Horn of Africa to Mozambique, scientists say.
Four countries in the Horn of Africa — Somalia and half of Ethiopia, Kenya and Tanzania — are expected to split from Africa to form a new continent — referred to as the Somali Plate — in about 50 million years.
Forces of the Earth are the strongest at the base of the valley, yet it is also here that geological processes are most active.
Suswa lies at the bottom of the valley.
“The valley has a history of tectonic and volcanic activities,” says geologist David Adede.
“Whereas the rift has remained tectonically inactive in the recent past, there could be movements deep within the Earth’s crust that have resulted in zones of weakness extending all the way to the surface.”
These zones of weakness form fault lines and fissures which are normally filled by volcanic ash, most likely from the nearby Mt Longonot.
The rains have only aggravated the situation by washing away the ash, eventually exposing the cracks.
Plate tectonics, or shifting of the Earth’s masses, is based on the argument that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core.
The Earth has nine major plates — the North American, Pacific, Eurasian, African, Indo-Australian, Australian, Indian, South American and Antarctic — named after the landforms on them.
Because of the problem deep within the Earth’s crust at Suswa, Mr Munene says, ongoing repair works by Kenya National Highways Authority, which include filling the gullies with concrete and rocks, will only provide a temporary solution.
“You cannot stop a geological process because it occurs from deep within the crust of the Earth,” he says.
More studies, therefore, need to be conducted in the area to understand the geology of the area and map the fault lines.
Geological investigations are normally mandatory for any major infrastructural projects such as roads, bridges and even high-rise buildings in danger zones, and Monday we could not establish the safety of the new railway line cutting through this valley in the wake of recent events.
Families living near the fissure started moving out yesterday, with 72-year-old Mary Wambui saying “staying here is like courting death”.
She was having dinner with the rest of the family on Monday when the Earth suddenly cracked beneath their feet, cutting their home into two.
While inspecting the damaged section last Tuesday, Infrastructure principal secretary Julius Korir admitted that the shifting fault line posed a huge challenge to engineers, who have in the past have blamed the geology of the area for the frequent disruption of transport on the road whenever it rains.
Source: Daily Nation