Frequent earthquake in Himalayas -are we learning any lessons from it? ........................( I need proper answer please help me ! I don't need any hint points I need proper answer please take it seriously................. I am not getting any solution over it am posting this question third time........please give me proper solution in 1000-1200 words)
Dear student,
The primary cause of large earthquakes and landslides in this region is the collision of the Indian plate with the Eurasian plate.
It is this ongoing collision that caused the Himalayas to build in the first place.
The sedimentary rock at the bottom of the former Tethys sea floor is now the rock firming MT Everest and the rest of the Himalaya mountains.
It has taken 100 million years to make the transition from seafloor sediment to towering mountains - and they are still growing.
Although monsoon rains cause landslides every year, economic activities and the climate crisis are increasing the risk, especially in the Himalayas
Last year, 264 Indians died in landslides, said a report on accidental deaths and suicides in 2019 by the National Crime Records Bureau. Over 65% of these fatalities happened in the Himalayas and the Western Ghats.
Human intervention
A landslide is a large movement of rock, debris or earth triggered by natural causes such as earthquakes or heavy rainfall. But human activity such as the construction of roads, buildings and railways, mining and quarrying and hydropower projects also damage hilly slopes and impact natural drainage by removing soil and vegetation, loosening soil and gravel and making the hills more susceptible to landslides. In India, 4,20,000 sq km, or 12.6% of the total land, is landslide-prone.
India was one of the countries most affected by human-triggered fatal landslides in the 2004-’16 period, found a study by researchers at Sheffield University, UK.
India accounted for 28% of construction-triggered landslide events, followed by China (9%), and Pakistan (6%). On the other hand, of the total landslides triggered by rainfall, 16% were reported from India. Of these, 77% occurred during the monsoon. India also accounted for maximum landslides triggered by mining, at 12%, followed by Indonesia (11.7%), and China (10%).
Unplanned development
A study analysing building regulations in eight towns in the Himalayan region found that these building bylaws do not make provisions for the particular geo-environmental context of a settlement. The same land use regulations apply regardless of topographical location, slope angle and direction, and the hazard potential of a site.
Mapping landslides can minimise damage
Improvement in early warning systems, monitoring and susceptibility zoning can reduce the damage caused by landslides.
The Geological Survey of India has done a national earthquake and landslide susceptibility mapping at 1:50,000 scale for 85% of the entire 4,20,000 square km landslide-prone area in the country and is trying to complete the rest in the next two years. The areas have been divided into different zones according to the propensity of the disaster. (Map scale refers to the ratio between the distance on a map and the corresponding distance on the ground. On a 1:50,000 scale, 1 cm on the map would denote 0.5 km on the ground.) Efforts are afoot to create maps that offer even greater accuracy in high hazard areas.
Planning ahead
Mizoram’s capital city Aizawl, which falls in the most seismically active Zone V, has taken a lead over other hill towns in this aspect. It has developed a landslide action plan using 1:5,000 scale susceptibility maps and new regulations to guide construction activities.
Aizawl Municipal Corporation has set up a landslide policy committee involving stakeholders from various departments and researchers to prepare a long-term safety plan. University students were involved to prepare susceptibility maps at 1:5,000 scale, identifying the risk zones.
Monitoring for early warning
Local geographical indicators offer warning signs for landslides and Earthquakes.. New cracks, unusual bulges and depressions in the ground, tilting trees, telecom poles or retaining walls, soil moving away from foundations and sudden increase in water flow in streams with more mud, or decrease in flow when it is still raining or rainfall has recently stopped, can signal landslides.
Note:- many times large scale movement of land and Earthquake has same reason.
Regards