CGPCS Prelims and Mains Notes, CGPCS Test Series
The Crust of Earth It is the outermost and the thinnest layer of the earth’s surface, about 8 to 40 km thick. The crust varies greatly in thickness and composition – as small as 5 km thick in some places beneath the oceans, while under some mountain ranges it extends up to 70 km … Read more
The continental drift theory is the theory that once all the continents were joined in a super-continent, which scientists call Pangaea. Over a vast period of time, the continents drifted apart to their current locations. Alfred Wegener first supported continental drift. Wegener’s explanation of continental drift in 1912 was that drifting occurred because of … Read more
Orogenic or the mountain-forming movements act tangentially to the earth surface, as in plate tectonics. Tensions produces fissures (since this type of force acts away from a point in two directions) and compression produces folds (because this type of force acts towards a point from two or more directions). In the landforms so produced, … Read more
The interaction of matter and temperature generates these forces or movements inside the earth’s crust. The earth movements are mainly of two types: diastrophism and the sudden movements. The energy emanating from within the earth is the main force behind endogenic geomorphic processes. This energy is mostly generated by radioactivity, rotational and tidal friction … Read more
Most of the knowledge we have about Earth’s deep interior comes from the fact that seismic waves penetrate the Earth and are recorded on the other side. Earthquake ray paths and arrival times are more complex than illustrated in the animations, because velocity in the Earth does not simply increase with depth. Velocities generally … Read more