Geography · General Awareness

Geology and Earth Structure

1,268 Questions

Geology and Earth Structure explores the physical composition of the planet, including its layers, tectonic plates, and seismic activity. This topic is a core component of geography and general science sections in various competitive exams. Reviewing these concepts builds a solid foundation for answering questions related to natural phenomena.

Layers of the EarthTectonic PlatesEarthquakes and VolcanoesGeomagnetism ApplicationsGeophysical MethodsLandform Formation

Geology and Earth Structure Questions

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

An earthquake is a defined as a tremor below the surface of the earth which causes ______________.

  1. shaking of the crust

  2. shaking of the sea

  3. shaking of the mountain

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An earthquake is a moment of tremor of the earth's crust. It originates naturally and below the surface. It sometimes causes a permanent change of level at the surface of the earth.

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

According to the plate tectonic theory, the crust of the earth is made up of series of ____________.

  1. plate

  2. movable plate

  3. stationary plate

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

According to the theory of plate tectonics, the world has been divided into six major plates and several smaller movable plates. Each of the plates is composed of crust up to a depth of 100 km from the surface of the earth. Due to the forces at the earth's interior, these plates move.

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

The point on the earth's surface vertically above the focus of Earthquake is called ______.

  1. pericentre

  2. epicentre

  3. both a and b

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The epicenter of an earthquake  is the point on the earth's surface vertically above the focus. Maximum damage is caused at the epicenter. 

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

P-waves of earthquake can pass through _________.

  1. solid, liquid, gas

  2. solid

  3. liquid

  4. gas
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

P- Waves or the primary waves are also known as longitudinal or compressional waves. It can pass through solid, liquid and gas. P- waves travel at the fastest speed through solid materials. Though these also pass through liquid and gaseous materials their speed is slowed down. 

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

S-waves of earthquake can only pass through ______________.

  1. Solids

  2. Liquids

  3. Gases

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

S-Waves or secondary waves are also called transverse or distortional waves. These are analogous to water ripples or light waves wherein the particles move at right angles to the rays. S- Wave cannot pass through liquid materials. It can only pass through solids.  

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

Anatomy of earthquake includes ______.

  1. P-waves

  2. S-waves

  3. T-waves

  4. All of these
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation
Multiple Answers
A. P-waves
B. S-waves

Two types of particle motion result in two types of body waves: Primary and Secondary waves.

Primary waves (P-waves) are compressional waves that are longitudinal in nature. P waves are pressure waves that travel faster than other waves through the earth to arrive at seismograph stations first, hence the name "Primary". These waves can travel through any type of material, including fluids, and can travel at nearly twice the speed of S waves. In air, they take the form of sound waves, hence they travel at the speed of sound.

Secondary waves (S-waves) are shear waves that are transverse in nature. Following an earthquake event, S-waves arrive at seismograph stations after the faster-moving P-waves and displace the ground perpendicular to the direction of propagation. Depending on the preoperational direction, the wave can take on different surface characteristics; for example, in the case of horizontally polarized S waves, the ground moves alternately to one side and then the other. S-waves can travel only through solids, as fluids (liquids and gases) do not support shear stresses

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

The point of origin of waves of earthquake is called as ________________.

  1. Seismic focus

  2. Seismic line

  3. Seismic centre

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Focus or Seismic Focus is also called the hypocenter of an earthquake. The vibrating waves travel away from the focus of the earthquake in all directions. The waves can be so powerful they will reach all parts of the Earth and cause it to vibrate like a tuning fork. The focus is the exact point inside the crust of the earth where the quake begins.

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

In 1906 San Andreas Fault of California gave rise to major earthquake because of __________.

  1. plate tectonic

  2. folding and faulting

  3. volcanic activity

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The San Andreas Fault is a transform plate boundary where the movement of tectonic plates causes folding and faulting of the Earth's crust, leading to earthquakes.

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

The vibration of earthquakes, last from a few seconds to several minutes, called as ______.

  1. duration

  2. period

  3. hour

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Duration is the vibration of earthquakes which can be felt by human beings that last from a few seconds to several minutes. Generally, the greater the intensity of the shocks, the longer they last. The average duration of shocks of sufficient intensity to produce much damage is perhaps from one to two minutes.

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

There are annually 8,000-10,000 earthquakes in the world, which comes to about an earthquake every hour known as, ____________.

  1. Earthquake velocity

  2. Earthquake frequency

  3. Earthquake wave

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are annually 8,000 - 10,000 earthquakes in the world, which comes to about an earthquake every hour. And there are many more that go undetected because there are no stations to record them over the oceans covering a very large surface of our earth. This is known as the Earthquake Frequency

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

A line connecting all points on the surface of the earth where the intensity of shock produced by earthquake waves is the same.

  1. Isosismic line

  2. Isohyte lines

  3. Isobars

  4. Isotherm lines
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Isoseismic Line is the line connecting all points on the surface of the earth where the intensity is the same. These lines show great irregularity in their form. 

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

The most destructive earthquake waves are ___________.

  1. primary waves

  2. secondary waves

  3. surface waves

  4. all of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

During an earthquake, surface waves are the seismic waves that cause the most damage. Unlike other seismic waves that move deep inside the Earth, surface waves move along just under the surface of the Earth like waves in water. Surface waves are the slowest seismic waves and are the final waves to hit an area after an earthquake. First, P-waves move through compression through the deep layers of the Earth. They result in minimal damage. The second group of waves is S-waves. They move up and down starting deeper in the Earth. Stronger S-waves do some damage when they reach the surface. Surface waves move in last. Their slow roll just under the surface provides the greatest risk for damage to man-made structures and changes to natural landforms

Multiple choice geography our changing earth earthquake and volcanoes earthquake earthquakes

The movement of the earth's plates causes __________.

  1. Cyclones

  2. Lightning

  3. Earthquakes

  4. Thunderstorms
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Earth's crust is divided into various plates which float on hot magma layer called asthenosphere. When these plates move, they interact with each other which releases energy, that is felt on the surface of earth as tremors or shaking movement, which is termed as earthquake.
  • Cyclones, thunderstorms and lightenings are the atmospheric phenomena and are not related with earth's surface, hence these 3 options are incorrect.