HIMALAYAS

Published on 31 Jan 2025

The Himalayas: Vast mountain range in Asia, home to the world's highest peaks like Mount Everest. It spans multiple countries, featuring diverse landscapes, cultures, and religious significance.

Formation of Himalayas ranges  

• Trans Himalayas: The movement of the Indian plate towards the Eurasian plate led to the subduction of the Tethys Sea. This resulted in the upliftment of the earth’s crust and volcanic activity leading to the formation of trans-Himalayan ranges.

• Himadri: Sediments accumulated in the Tethys Sea were compressed, and squeezed by the movement of the Indian and Eurasian plates leading to the extreme upliftment of the Himadri region which is the most continuous and contains the loftiest peaks. 

• Himachal: The collision between Indian and Eurasian plates created the most rugged part of the Himalayas with altered rocks i.e. Himachal Himalayas.

• Siwalik: Formed from the consolidated sands, gravels and conglomerate deposits [Alluvial fans] which were brought by the rivers flowing from the higher ranges.

Characteristic features of Himalayas

• High Peaks: Home to the world's highest peaks and continuous presence of snow-capped summits.

• Example: Mount Everest, K2 

• Ongoing tectonic activity: Formed due to the collision between the Indian and Eurasian tectonic plates and still undergoing upliftment.

• Diverse geology: Varied geological formations, including sedimentary rocks in the foothills and crystalline rocks in the higher ranges.

• Example: Granitic rocks of Himadri and sedimentary rocks of Shiwaliks 

• Glacial Features: Extensive glacial activity with numerous glaciers creating glacial valleys and moraines contributing to the landscape.

• Example: Baltoro, Siachin, Gangotri etc 

• River systems:  Origin of major rivers thus playing a major role in the region's hydrology and agriculture.

• Example: Origin of India’s major river systems- Ganga, Brahmaputra, Yamuna etc 

• Diverse Climate Zones: Varied climatic conditions, ranging from alpine in the higher reaches to subtropical in the foothills.

• Fault lines: Presence of major fault lines due to tectonic forces. 

• Example: Main Central Thrust and Main Boundary Thrust

Vulnerability of Himalayas

The Himalayas face various vulnerabilities, making the region susceptible to environmental, social, and economic challenges. Some key vulnerabilities include:

• Earthquake: Seismic event in the Himalayan region, resulting from tectonic activity, causing widespread damage and geological shifts.

• Example: 2015 Nepal earthquake 

• Landslide: Mass movement of rocks and soil in the Himalayas, triggered by factors like heavy rainfall or earthquakes, causing significant terrain changes.

• Example: 1998 Malpa Landslide in the UP 

• Land subsidence: Gradual sinking or settling of the Earth's surface in the Himalayas, often due to geological processes or human activities.

• Example: Joshimath land subsidence 2023

• Floods: Flash floods and frequently changing water levels leading to inundation of land

• Example: 2013 Uttarakhand floods 

• Cloudburst: Sudden, intense rainfall, often from a single convective cloud, causing rapid and massive downpours, leading to flash floods.

• Example: Frequent cloudbursts in Himachal Pradesh and Uttarakhand

• Glacial lake outburst: Rapid release of water from a glacier-dammed lake, causing downstream flooding.

• Example: Glacial lake outburst in Sikkim 2023

• Dam failure: Uncontrolled breach or collapse of a dam structure, leading to the release of stored water and potential downstream flooding.

Causes of vulnerabilities 

• Climate change: Altered weather patterns, glacial melting, and ecological shifts due to global warming, causing heavy and concentrated rainfalls 

• Tectonic activity: Himalayas are still tectonically highly active due to the ongoing movement of the Indian plate towards the Eurasian plate thus causing earthquakes and landslides.

• Changing river course: Villages of Assam and Arunachal Pradesh disappearing as young Himalayan Rivers such as Brahmaputra shift their course frequently.

• Unconsolidated materials: The Shiwaliks range is primarily composed of unconsolidated sediments, such as sand, gravel, silt, and clay which cause high damage on ground shaking and earthquakes.

• Deforestation: Increased deforestation because of firewood collection, agriculture and thus changing land use patterns. 

• Developmental activities: Road development initiatives like Chardam projects, tunnels, hydropower projects etc increase the vulnerability of already unstable Himalayas.

Tags:
Geography

Keywords:
HIMALAYAS India physiographic divisions Formation of Himalayas ranges trans himalaya himachal himadri siwalik Characteristic features of Himalayas Vulnerability of Himalayas Causes of vulnerabilities of Himalaya

Syllabus:
General Studies Paper 1

Topics:
Salient Features of Indian Geography