Mastering KCSE Geography: Topical Questions and Answers for Effective Revision - ATIKA SCHOOL

How compressional forces can lead to the formation of a rift valley

9/7/2023

How compressional forces can lead to the formation of a rift valley

Explanation;

Layers of crustal rocks are subjected to compressional forces
Two almost parallel reverse faults develop
Outer blocks are thrust upwards and pushed over the middle block
Middle block sinks / remains at a lower level forming the floor of a rift valley
The overhanging parts are eroded by erosion / collapse

Name three characteristics of the rift valley lakes of Kenya

5/7/2023

Name three characteristics of the rift valley lakes of Kenya

Some lakes lacks outlets
Some lakes are located I areas which are hot ad dry
Some lakes do not have enough fresh water rivers emptying into them
Some lakes are fed with water from the under ground

With the aid of well-labelled diagrams describe the formation of rift Valley by compressional forces. (7 marks)

4/7/2023

With the aid of well-labelled diagrams describe the formation of rift Valley by compressional forces. (7 marks)

the crustal rock layers are subjected to forces of compression
This leads to formation forces to formation of parallel reversed faults towards each other.
The compressional forces push the outer blocks towards each other
The outer blocked one force upwards uplift or hung over the middle block.
The middle block sinks or may remain at the lower level.
The sunken middle block form a depression having sleep fault scarps called rift valley

State three characteristics of the Gregory Rift valley of Kenya

1/7/2023

State three characteristics of the Gregory Rift valley of Kenya. (3 marks)

The height of escarpment varies at various points
The altitude at the floor of the rift valley differs at various points
The width of the rift valley varies at different points.
A number of volcanoes occur on the floor of the rift valley.
Uneven sinking created depressions that are occupied with water forming lakes.
Several fault blocks border the rift valley.
Step faulting is evident near Kimende and at Tambach.