Dozens killed as dam bursts in flood-hit Kenya

The banks of a dam burst near a town in Kenya's Rift Valley, resulting in the tragic deaths of more than 42 people. The country was affected by heavy rains and floods.

1. The disaster brings the total death toll from Kenya's March–May season to more than 120, as the El Nino weather pattern in East Africa has brought heavier than normal rainfall.

About Great Rift Valley:

1. The Great Rift Valley is one of the most extensive rifts on the Earth's surface, extending across part of East Africa.
2. It runs for approximately 4,000 miles (6,400 kilometers), starting in Jordan in southwestern Asia and extending to the Indian Ocean coast in central Mozambique.
3. The Great Rift Valley passes through several countries, including Eritrea, Djibouti, Ethiopia, Kenya, Tanzania, Uganda, Rwanda, Burundi, Democratic Republic of the Congo (DRC), Malawi, Zambia, and Mozambique.
4. The Great Rift Valley is part of a larger feature known as the East African Rift System (EARS).

Formation and Features:

1. The valley is located in a region where 3 tectonic plates meet: Arabian, Nubian, and Somalian plates, and it formed approximately 40 million years ago due to the splitting of tectonic plates.

2. The valley's width ranges from 30 to 40 miles (48 to 64 kilometers) on average, but at its widest point in the Danakil Desert of northeastern Africa, it spans nearly 300 miles (480 kilometers).
3. The area exhibits geological activity, featuring volcanoes, hot springs, geysers, and frequent earthquakes.
4. Along the valley's length, a series of approximately 30 lakes can be found. 
5. 3 of the largest lakes in Africa, known as the Great Lakes, are found within the valley: Lake Tanganyika (the world's 2nd-deepest lake) and Lake Victoria (the world's 2nd-largest freshwater lake by surface area).
6. In the ranges bordering the Rift Valley, several of Africa's highest mountains are located, including Mount Kilimanjaro, Mount Kenya, and Mount Margherita.

What are Rift Valleys?

1. A rift valley is a depression formed when tectonic plates on Earth's surface move apart.
2. Rift valleys are not only found on land but also at the bottom of the ocean, created by the process of seafloor spreading.

What are Tectonic Plates?

1. Tectonic plates are pieces of Earth's crust and uppermost mantle, collectively known as the lithosphere.  They consist of 2 primary types of material: oceanic crust and continental crust.
2. These plates rest above a partially molten layer of rock called the asthenosphere, and their motion relative to each other is driven by convection within the asthenosphere and lithosphere.

Plate Boundaries:

The edges where these plates meet are called plate boundaries:

1. Divergent boundaries: Plates move apart at these boundaries, allowing new crust to form from molten rock rising from the mantle. The Mid-Atlantic Ridge is a classic example, where new oceanic crust continuously pushes continents apart, creating the Atlantic Ocean.

1. Example - Mid-ocean ridges: Mid-Atlantic Ridge, East Pacific Rise, Gakkel Ridge.

Rift valleys: African Rift Valley, Rhine Graben.

2. Convergent boundaries: When plates collide, they can compress, twist, and even bend (one plate gets pressed under the other). This creates mountain ranges such as the Himalayas and the Andes, and can cause earthquakes and volcanic eruptions.

1. Example - Subduction zones: Cascadia Subduction Zone, Mariana Trench, Tonga Trench. Collision zones: Himalayan Mountains, Appalachian Mountains, Ural Mountains.

3. Transform boundaries: These boundaries are like faults where plates slide past each other horizontally. A famous example is the San Andreas Fault in California, where the Pacific Plate passes through the North American Plate.

1. Example- San Andreas Fault: California, USA. Dead Sea Transform: Israel, Jordan, Palestine. North Anatolian Fault: Turkey.

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