Points to Remember:
- The three main mountain ranges in Uttarakhand are the Himalayas, the Siwalik Hills, and the Lesser Himalayas.
- Thrusts are geological features representing major fault planes where older rocks are pushed over younger rocks.
- Identifying the thrusts separating these ranges requires understanding Uttarakhand’s geological formation.
Introduction:
Uttarakhand, nestled in the Himalayas, boasts a complex geological history shaped by tectonic forces. The state’s landscape is characterized by three major mountain ranges: the Great Himalayas (also known as the Himadri), the Lesser Himalayas (also known as the Himachal), and the Siwalik Hills. These ranges are not simply stacked upon each other but are separated by significant geological structures known as thrusts â major fault planes where older rock masses have been pushed over younger ones. Understanding these thrusts is crucial to comprehending the region’s geological evolution and its susceptibility to seismic activity.
Body:
Identifying the Thrusts:
The three main thrusts separating the three major mountain ranges in Uttarakhand are:
Main Central Thrust (MCT): This is the most significant thrust separating the Great Himalayas (Himadri) from the Lesser Himalayas (Himachal). The MCT represents a major tectonic boundary where the older crystalline rocks of the Himalayas have been thrust over the younger sedimentary rocks of the Lesser Himalayas. It’s a complex zone of deformation and is associated with significant seismic activity.
Main Boundary Thrust (MBT): This thrust separates the Lesser Himalayas (Himachal) from the Siwalik Hills. The MBT marks the boundary between the relatively higher-grade metamorphic rocks of the Lesser Himalayas and the less deformed sedimentary rocks of the Siwalik Hills. This thrust is also associated with significant faulting and folding.
Himalayan Frontal Thrust (HFT): This thrust marks the southernmost boundary of the Siwalik Hills, separating them from the Indo-Gangetic plains. The HFT is responsible for the formation of the foothills and is characterized by relatively recent tectonic activity.
Geological Significance:
These thrusts are not just lines on a map; they are zones of intense geological activity. The movement along these thrusts has shaped the landscape, created valleys, and continues to influence the region’s seismicity. The Himalayas are still actively rising due to the ongoing collision of the Indian and Eurasian plates, and these thrusts are key players in this process. Understanding their behavior is crucial for assessing seismic hazards and mitigating risks.
Conclusion:
In summary, the Main Central Thrust (MCT), Main Boundary Thrust (MBT), and Himalayan Frontal Thrust (HFT) are the three primary thrusts separating the Great Himalayas, Lesser Himalayas, and Siwalik Hills in Uttarakhand. These thrusts are critical elements of the region’s geological structure and are responsible for its complex topography and susceptibility to earthquakes. Further research and monitoring of these thrusts are essential for effective disaster preparedness and sustainable development in the region. A holistic approach incorporating geological understanding with robust infrastructure planning and community awareness programs is vital for ensuring the safety and well-being of the people of Uttarakhand while respecting the delicate ecological balance of this unique Himalayan region.
UKPCS Notes brings Prelims and Mains programs for UKPCS Prelims and UKPCS Mains Exam preparation. Various Programs initiated by UKPCS Notes are as follows:-- UKPCS Mains Tests and Notes Program
- UKPCS Prelims Exam 2024- Test Series and Notes Program
- UKPCS Prelims and Mains Tests Series and Notes Program
- UKPCS Detailed Complete Prelims Notes