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Summary

Geography Class 18

## A brief review of the previous class and doubts

. (5:08 PM)

## Types of Mass Movements

.

- ==Slow==:
- ==Creep==: The slow downhill movement of the soil and weathered mantle along the mountain slopes.
- It is a continuous movement but difficult to notice
- ==Solifluction==: It involves the slow movement of soil mixed with water as a viscous fluid
- It is more active in glacial areas
- ==Rapid:==
- ==Landslide:== A landslide is the movement of a cross-section of a hill slope under the influence of gravity is called as landslide
- The material maintains continuous contact with the surface as it moves
- ==Avalance==: Similar to landslides, is sudden collapse and sliding of snow-covered regions
- ==Earthflow==: Thye occur along terraces and hillsides that are capable of flowing as a single unit when saturated with water below the top layer
- ==Mudflow==: It involves the rapid movement of masses of uncompacted soil ie suddenly saturated with water
- ==Rock slide/fall==: It is a rapid movement including rock material either sliding along the mountain slopes (rock slide) or falling vertically

## Landforms

: (6:04 PM)

- ==Agent and its topography:==
- River - Fluvial Topography
- Ground - Karst topography
- Waves - marine Topography
- Wind - Desert or Arid Topography
- Glacier - Glacial topography
- Each causes erosional as well as depositional topography

## Riverine Topography

:

- It is a topography which is built by riverine erosional and deposition
- 3 stages in riverine topography: Youth Stage, Mature Stage, and Old Stage
- |  |  |  |  |
  | --- | --- | --- | --- |
  | ==Index== | ==Youth Stage== | ==Mature Stage== | ==Old Stage== |
  | Slope | High | Moderate | Low |
  | Energy | High | Moderate | Low |
  | Erosion | High - Vertical | Moderate Lateral | Low or No erosion |
  | Deposition | Very low | Moderate | High |
  | Meandering | No | Moderate | High |

## Features of Riverine Topography:

(6:52 PM)

- |  |  |  |  |
  | --- | --- | --- | --- |
  | Topography | Processes | Erosional | Depositional |
  | - Riverine (Agent - River water) | - Corrasion - Attrition - Cavitation - Corrosion - Hydraulic - V-Shaped Valleys | - V-Shaped Valleys - Gorge and Canyon - Waterfall, Cataract, Rapids - Plunge pools and Pot Holes - River Capture and wind Gap - Meander - River Cliff | - Slip of slope - Levee - Flood Plain - Ox-Bow lakes - Alluvials fans and Delta - Estuary |

## Topics for the next class

: Continuation of Landforms, etc