Outline the Causes of Earthquakes.
Natural Causes
(a) Tectonic movements e.g. movement of tectonic plates. They cause tectonic earthquakes.
(b) Vulcanicity when magma movement displaces rocks suddenly shaking and shuttering them.
(c) Gravitative force when crustal rocks collapse into cauldron due to gravity.
(d) Energy release in the mantle when radioactivity takes place in mantle releasing explosive energy which sends shock waves outwards.
(e) Isostatic adjustment when the continental masses rise to restore the upset state of balance between sial and sima layers.
Human Causes
(a) Exploding nuclear bombs underground which causes shock waves which spread outwards and are felt in the neighborhood.
(b) When a train rolls on its rails causing the ground to vibrate.
(c) Explosion of explosives used in mining and quarrying which cause vibrations to be felt in the neighborhood.
(d) When large reservoirs are constructed and the heavy weight of water reactivate dormant faults causing tremors.
OR
(i) Folding or faulting.
(ii) Isostatic adjustment
(iii) Energy release within the mantle.
(iv) Blasting of rocks or bomb explosions or construction of large reservoirs.
(v) Movement of magma within the earth's crust or volcanic eruption.
maurice.mutuku answered the question on June 5, 2017 at 12:28
-
What are the scales used to measure the intensity of an earthquake?
(Solved)
Name the scales used to measure the intensity of an earthquake.
Date posted:
June 5, 2017
.
Answers (1)
-
In which ways is the earth's crust affected by earthquakes?
(Solved)
Explain ways in which the earth's crust is affected by earthquakes.
Date posted:
June 5, 2017
.
Answers (1)
-
What are the types of earthquake waves?
(Solved)
Give the types of earthquake waves.
Date posted:
June 5, 2017
.
Answers (1)
-
What are earthquakes?
(Solved)
Describe earthquakes.
Date posted:
June 5, 2017
.
Answers (1)
-
How is a parasitic cone formed?
(Solved)
Describe how a parasitic cone is formed.
Date posted:
June 5, 2017
.
Answers (1)
-
How is a crater formed?
(Solved)
Describe how a crater is formed and give an example.
Date posted:
June 5, 2017
.
Answers (1)
-
What is the difference between magma and lava?
(Solved)
Explain the difference between magma and lava.
Date posted:
June 5, 2017
.
Answers (1)
-
In which ways do volcanic mountains influence human activities positively?
(Solved)
Discuss ways in which volcanic mountains influence human activities positively.
Date posted:
June 5, 2017
.
Answers (1)
-
What are the characteristics of a composite volcano?
(Solved)
Explain the characteristics of a composite volcano.
Date posted:
June 5, 2017
.
Answers (1)
-
Explain how a sill is formed
(Solved)
Explain how a sill is formed.
Date posted:
June 5, 2017
.
Answers (1)
-
How was Mt. Kenya formed?
(Solved)
Discuss how Mt.Kenya was formed.
Date posted:
June 5, 2017
.
Answers (1)
-
Which volcanic features are found in the rift valley of Kenya?
(Solved)
Name volcanic features found in the rift valley of Kenya.
Date posted:
June 5, 2017
.
Answers (1)
-
In which ways are the features resulting from faulting of significance to the economy of Kenya?
(Solved)
Explain four ways in which features resulting from faulting are of significance to the economy of Kenya.
Date posted:
June 5, 2017
.
Answers (1)
-
In which ways does faulting influence drainage systems?
(Solved)
Discuss ways in which faulting influence drainage systems.
Date posted:
June 5, 2017
.
Answers (1)
-
What is the significance of faulting to human activities?
(Solved)
Discuss the significance of faulting to human activities.
Date posted:
June 5, 2017
.
Answers (1)
-
Apart from compressional forces,what other processes causing faulting?
(Solved)
Apart from compressional,name other processes that may cause faulting.
Date posted:
June 5, 2017
.
Answers (1)
-
What are the types of faults?
(Solved)
Name types of faults.
Date posted:
June 5, 2017
.
Answers (1)
-
Students at Fuzu Secondary school are planning to carry out a field study of an area affected by faulting,Why is it important for the students to have a pre-visit of the area?
(Solved)
Explain why it is important for the students to have a pre-visit of an area affected by faulting before carrying out a field study.
Date posted:
June 5, 2017
.
Answers (1)
-
What are the disadvantages of direct observation in the study of an area affected by faulting?
(Solved)
Give the disadvantages of direct observation in the study of an area affected by faulting.
Date posted:
June 5, 2017
.
Answers (1)
-
Apart from the Rift Valley,what other relief features are formed as a resulting of faulting?
(Solved)
Apart from the Rift Valley,name other relief features that were formed as a result of faulting.
Date posted:
June 5, 2017
.
Answers (1)