Landslide -Natural Hazard. '

Here we presenting a seminar about landslide, landslide is a natural hazard that causes many accidents and calamities. Here we analysing some of the reasons, causes and remedies, may be it will help you to get some basic idea about landslide.

1. WELCOME BSC GEOLOGY FIRST YEARS PRESENTS M. E. S PONNANI COLLEGE [SEMINAR]

2. NATURAL HAZARDS

3. LANDSLIDES TOPIC:

4. What is landslides?

5. A landslide is a mass movement of material, such as rock, earth or debris, down a slope under the influence of gravity.

6. Types of landslide

7. Rotational slides occur on curved slip surfaces where the upper surface of the displaced material may tilt backwards toward the scarp.

8. Translational slide In this type of slide, the landslide mass moves along a roughly planar surface with little rotation or backward tilting.

9. Rockfall Rockfalls are abrupt movements of masses of geologic materials, such as rocks and boulders, which become detached from steep slopes or cliffs. Separation occurs along discontinuities such as fractures, joints, and bedding planes, and movement occurs by free-fall, bouncing, and rolling. Falls are strongly influenced by gravity, mechanical weathering, and the presence of interstitial water.

10. Rock topling Topple failures involve the forward rotation and movement of a mass of rock, earth or debris out of a slope. This kind of slope failure generally occurs around an axis (or point) at or near the base of the block of rock.

11. Lateral spreading in fine-grained materials on shallow slopes is usually progressive. The failure starts suddenly in a small area and spreads rapidly. Often the initial failure is a slump, but in some materials movement occurs for no apparent reason. Lateral spreading

12. Debris flows are fast-moving landslides that are particularly dangerous to life and property because they move quickly, destroy objects in their paths, and often strike without warning. Debris flow

13. What are the Causes?

14. Gravity: Gravity works more effectively on steeper slope. Heavy and prolonged rainfall creating zone of weakness also water table rises with heavy rain makes some slope unsable. Earthquakes: ground vibrations creating during earthquakes. Waves: wave action can erode the beach of the toe of the bluff cutting into the slope and setting the stage for future slides. Volcanoes Fluctuation of water levels due to tibel action.

15. What are the after effects ?

16. Physical Damage: Debris may block the roads, supply lines (telecommunication, electricity, water) and waterways Causaliteis: Death and injuries to people and animal Influence of landslides in dam safety: Failure of the slope boarding the reservoir, flooding cause by movement of large masses of soil into the reservoir. Landslides and flooding: Debris flow can cause flooding by blocking valleys and stream channels forcing large amount of water to backup causing flash flood Direct effect Indirect effect

17. How to Prevent ?

18. Landslides are a natural phenomenon, and while we cannot prevent them entirely.

19. As experts suggest, reducing human interventions in ecologically sensitive areas can help avoid exacerbating these disasters. Choose a safe location to build your home, away from steep slope Prevent deforestation and vegetation removal. Avoid weakening the slope ➤ Reforestation Drainage: Good ground drainage is essential to prevent saturation and consequent weakening. ➤ Proper water runoff must be ensured by providing proper chanalisation

20. S D M A(State Disaster Management Authoritrhy)---04712331345 ,1079 Available helpline numbers District Emergency Operation Centre (DEOC) -1077

21. Major geological hazards (landslides) occured in india

22. Wayanad,Mundakkai (2024)-debris flow Karanataka, ankola, shirur (2024) Guwahati, Assam. September 18, 1948. ... Darjeeling, West Bengal. October 4, 1968. ... Malpa, Uttarakhand. August 18, 1998. ... Mumbai, Maharashtra. July 12, 2000. ... Amboori, Kerala. November 9, 2001. ... Kedarnath, Uttarakhand. June 16, 2013. ... Malin, Maharashtra. July 30, 2014. ... Pettimudi, Kerala. August 6, 2020.

23. OUR TEAM VALEED SHIBIL SHIFANA FATHIMA NASRIN JYOTHIKA ANAGHA KRISHNAKRIPA

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