Internal Land-Forming Processes and the Rift Valley

<h3>The restless earth beneath Kenya</h3><p><strong>Internal land-forming processes</strong> are movements driven by forces inside the earth that build and shape landforms. They include <strong>earth movements</strong> such as the slow drifting of continents and the cracking of the crust.</p><p>The <strong>continental drift theory</strong>, proposed by Alfred Wegener, states that today's continents were once joined as one giant landmass that slowly broke apart and drifted to their present positions. Evidence includes matching coastlines and similar rocks and fossils on different continents. The <strong>plate tectonic theory</strong> explains <em>how</em>: the earth's outer shell is broken into large pieces called <strong>plates</strong> that float on softer rock below and move very slowly, dragging the continents along.</p><p>Where the crust is placed under tension or compression it may crack and slip &mdash; this is <strong>faulting</strong>. Blocks can drop down or rise up, producing valleys, escarpments and block mountains. The most famous result in our region is the <strong>Great Rift Valley</strong>, formed mainly by tensional forces pulling the crust apart so that the central block sank.</p><div class="callout"><strong>Kenyan context:</strong> The Great Rift Valley running through Naivasha, Nakuru and Baringo was shaped by faulting. It gives Kenya rift lakes, fertile volcanic soils for farming, dramatic escarpments, and at Olkaria the geothermal steam that generates clean electricity.</div>