This document defines weathering as the process of disintegration and decomposition of rocks at the Earth's surface. It discusses two main types of weathering: mechanical and chemical. Mechanical weathering is the breakdown of rocks through physical processes without changing their chemical composition. Some key agents of mechanical weathering discussed are frost action, pressure release, insolation, and block disintegration.

1. Presented By:
Nirmal Roshan.R
&
M.R.Balaraman

2.  Introduction
 Definition
 Weathering
 Types of weathering
 Mechanical weathering
 Agents of Mechanical weathering
 Frost Action
 Pressure Release (Exfoliation)
 Insulation
 Some minor Agents of Mechanical weathering

3.  “Weathering is the process of disintegration and
decomposition of rocks of the earth’s surface”.
 Weathering

4.  Mechanical weathering
 Disintegration by physical agents
 Composition of rock does not change

5.  Frost Action
 Weathering process by ice
 Water increases in volume by about 9% when it
freezes
 Produces about 1890 metric tons pressure for every 1
ft2
 Common in high altitude zones

7.  Pressure Release (Exfoliation)
 Metamorphic and intrusive igneous rocks are under
pressure
 Upper layer is removed by erosion
 Due to pressure release the cracks are formed

9.  Insolation
 Common in arid and desert regions
 Temperature is high in day time and low in night
 Disintegration due to expansion and contraction
 Block Disintegration
 Granular disintegration

11.  Rainfall
 Gravity
 Salt wedging