Context:
Icelandic Meteorological Office (IMO) raised concern of an imminent volcanic eruption as Iceland experienced 2,200 earthquakes in the last 24 hrs.
Key Points:
- Iceland is Europe’s largest and most active volcanic region due to its presence on the Mid-Atlantic Ridge.
- Divergence of Plates –
- Plates: Eurasian and North American plates
- Effects: Earthquake Swarms, creation of Hotspots
- Major earthquake zones in Iceland: Mount Fagradalsfjall (Reykjanes Peninsula) and Eyjafjallajokull.
About Earthquake Swarms:
- They are sequences of many earthquakes that occur in a relatively short period without a specific fore shock, main shock or after Shocks.
- It can last for hours, days, or even weeks.
- Magnitudes: Low, Moderate and even High
- Prevalence of Occurrence –
- Relatively shallow depths within the Earth’s crust
- Existing fault systems
What is an Earthquake?
Any sudden shaking of the ground caused by the passage of seismic waves (Body Waves, Surface Waves, Rayleigh and Love) through Earth’s rocks.
Source: DNA
Consider the following statements:
- In a seismograph, P waves are recorded earlier than S waves.
- In P waves, the individual particles vibrate to and fro in the direction of wave propagation whereas in S waves, the particles vibrate up and down at right angles to the direction of wave propagation.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2023 Prelims]
- 1 only
- 2 only
- Both 1 and 2
- Neither 1 nor 2
