Sign up now
to enroll in courses, follow best educators, interact with the community and track your progress.
Earthquakes & Volcanoes - Physical Geography
15,351 plays

The earthquakes and volcanoes are natural phenomenon and these geomorphic phenomenon have been explained by Bhanwar in this lesson along with related processes and phenomenon.

Bhanwar Singh
Ex- National Defence Academy (115 Course) Cleared Civil Services Examination, 2012

Unacademy user
Simbex is the naval exercise between India and singapore (additional information)
sir thank you very much for work . sir please try to do on indian geography also sir
sir can i write in project file becz i prepared project file
sir the info being conveyed is outstanding... but it smetimes feels boring it could be made more interactive and what is important for exam point of view with several questions.
  1. CRASH COURSE-WORLD GEOGRAPHY Presented by - Bhanwar Singh Sirohi


  3. ABOUT ME BA. (Hons) in Law from Awadh University I Defence Academy (115 Course) Cleared Civil Services Examination, 2012 Hobbies - Writing Poetry Course Fee Contribute Follow me on Unacademy at:

  4. EARTHQUAKE The point from where earthquake originates which lies inside the earth crust is called the Focus of the earthquake The point perpendicular above the Focus, on the surface of the earth where earthquake is experienced for the first time is called the Epicenter The lines ioining the regions of same seismic intensity are called Isoseismal lines The lines joining the regions which experiences the earthquake at the same time are called Homoseismal lines The area on the Earth's surface which do not experiences the effects of P and S waves is known as Shadow Zone Before earthquake strikes a place, the amount of Radon gas increases in the atmosphere of that region

  5. CAUSES OF EARTHQUAKES Tectonic Process Sudden movement of crustal blocks along fault lines Volcanic Eruption Anthropogenic disturbance of the isostatic balance of Earth Crust water pressure Contraction of earth surface Expansion of gases

  6. EARTHQUAKE WAVES There are two types of waves that originates during an earthquake Body Waves Surface Waves Body waves originates from the focus and travel inside the Earth's surface. These waves can be classified into Primary or P waves Secondary or S waves Surface waves are those waves which are experienced on the surface of the earth and it is known as L Waves

  7. CHARACTERISTICS OF WAVES PRIMARY OR P WAVES Also known as Longitudinal waves and are analogous to sound waves These are fastest moving waves and thus are the first ones to be recorded by seismograp They can travel through solid as well as liquid medium SECONDARY OR S WAVES Also known as Transverse Waves and are analogous to light waves They have intermediate speed and cannot travel through liquid medium SURFACE OR L WAVES These are analogous to water waves and originate from Epicenter and not Focus Most destructive of all types of seismic waves and have least speed of them

  8. Ground mo tio n 20. Time (seconds)


  10. VOLCANISM Volcano-it is a vent or opening usually circular or nearly circular in form, in the Earth's crust, through which molten magma, gases, water vapour and fragments of rocks erupts suddenly Volcanism or Vulcan-city includes all the phenomenon that is associated with Volcanic eruption right from movement of magma to getting it cooled in various forms either on the surface of the earth or beneath it Magma-it is the molten silicate material that is combination of solid, liquid and gas mixture. Magma is of two types: Basaltic: which is fluidic a Granitic: which is viscous