"When you are inspired by some great purpose, some extraordinary project, all your thoughts break their bounds. Your mind transcends limitations, your consciousness expands in every direction, and you find yourself in a new, great and wonderful world. Dormant forces, faculties and talents come alive, and you discover yourself to be a greater person by far than you ever dreamt yourself to be."
Maharishi Patanjali Yoga Sutra before 2200 years.
Earth's structure has three parts — an outer silicate solid crust (till about
30km from the surface), a viscous mantle (2,900km thick) below the crust and a
core (3,500km diameter) at the center. The uppermost part of the mantle and the
crust is broken into seven major tectonic plates — African, Australian,
Eurasian, North American, South American, and Pacific. The motion of these
plates against each other causes earthquakes.
How is an earthquake measured?
in the form of seismic waves is released after an earthquake and seismometers
measure its amplitude to calculate the quake's intensity. For a long time,
earthquakes were measured on the Richter scale. Since the scale was based on
conditions in California and was not reliable in measuring large earthquakes,
it was replaced by a 'moment magnitude' scale in the 1970s.
Why is the Himalayan region more
prone to earthquakes?
Indian plate, which is part of the Indo-Australian plate, is moving in a
north-north-east direction and colliding with the Eurasian plate. The Himalayas
came up as a result of this movement. The collision has resulted in the
formation of many fault lines along the region, which has made it highly
susceptible to earthquakes.
Which regions of earth are most
susceptible to earthquakes?
Pacific 'Ring of Fire', a horseshoe shaped region encircling the Pacific Ocean,
accounts for 90% of all earthquakes. This 40,000 km long stretch has 452
volcanoes and is home to over 75% of the world's volcanoes. The next most
active region is the Alpide belt, which lies along Java, Sumatra, the
Himalayas, the Mediterranean, and the Atlantic Ocean.
What are the various seismic zones
to the Indian metrological department, the Bureau of Indian Standards has
grouped the country into four seismic zones, from Zone V, the most active, to
Zone II, the least active. Zone V consists of parts of Jammu and Kashmir,
Himachal Pradesh, Uttarakhand, Rann of Kutch, part of north Bihar and the
Andaman & Nicobar Islands. The remaining parts of Jammu & Kashmir and
Himachal Pradesh, Delhi, Sikkim, northern Uttar Pradesh, Bihar and West Bengal,
parts of Gujarat and small portions of Maharashtra near the west coast and
Rajasthan fall under zone IV (severe intensity zone).