The major physiographic divisions of West Bengal are as follows:
- Extra peninsular mountainous terrain of Darjeeling Himalayas
- Piedmont plain of North Bengal comprising Bhabar-Terai belt
- Peninsular shield area of South-Western Bengal
- Gondwana platform
- Vast low-lying alluvial tract of the southern and eastern part
- Coastal tract of Bengal basin
The northern mountainous terrain covers Darjeeling and part of Jalpaiguri districts. The southwestern Peninsular tract is, in fact, the eastern extension of Chhotonagpur plateau exhibiting rolling topography comprising Purulia, Medinipur, Bankura, Birbhum and part of Bardhaman districts.
North Bengal plain start from the south of Terai region and continues up to the left bank of the Ganges. The southern parts of the district Jalpaiguri, North Dinajpur baring some extreme northern regions, South Dinajpur, Malda, Alipurduar and southern part of Cooch Behar districts constitute this geographical region. The narrow land mass in the North Dinajpur district is known as Mahananda Corridor. This corridor runs north to south joining Malda with the plains of Jalpaiguri, Alipurduar and Cooch Bihar.
The river Ganga flowing from west to east (as Padma, through Bangladesh) and to south (as Bhagirathi) constitutes the major drainage of the central southern part of the state. The drainage is controlled by a number of rivers and streams, viz., Damodar-Kangsabati-Ajoy-Mayurrakshi etc. in the western part. In North Bengal, the Tista, the main drainage channel is controlled by Jaldhaka-Torsa-Raidak-Sankosh-Gangadhar rivers, etc. which are in turn, linked with the Brahmaputra river. Besides, Jalangi, Churni, Jamuna, Ichhamati, Bidyadhari, Matla, Raimongal, Gosaba etc. are some of the principal tributaries or distributaries of Bhagirathi draining different parts of the state. Bengal is proverbially associated with delta. The South Bengal Delta, one of the biggest of its kind is formed by the combined effect of two major rivers, the Ganga and the Brahmaputra along with their tributaries. Major part of the delta is in Bangladesh. An area of approximately 65,000 sq. km. of the Bengal delta is situated in the state of West Bengal. Topographically, the area is gentle to moderately flat with certain microrelict of at places. Drainage is consequent in nature, parallel to sub parallel in the north-western part gradually changing to dendritic to anastomosing towards south-east and anastomosing in tidal flat region. Structurally, Ganga-Brahmaputra delta can be divided into two parts. An imaginary line may be drawn from Kolkata to Maymansingh in the north-east, to understand the division. The slope in the north-western part of this line is only 2 to 3 degree, but, it increased to 6 to 12 degrees in the south-eastern part. Geoloists gave the name of this line as ‘eosine hinge zone’ or ‘KolkataMaymansingh Hinge Zone’.
The Sundarbans is the active part of the Ganga delta. It extends between the Hooghli mouth and Bangladesh comprising 15 thanas (police stations) of south 24-Parganas. To its north and east lie the mature and the moribund delta. The Sundarbans is named after the beautiful ‘SUNDARI’ redwood tree of the tidal forests. The region is still a terra incognita of swampy islands, rivers and mysterious tidal creeks. The land gradually declines to the seaboard which is half-land, half-water, rising and falling with the tides.
A 15 km. wide coastal strip of Midnapur district extends between the Bengal-Orissa border in the west and the Haldi River and mouths of the Hoogly River in the east. This strip has been built up jointly by riverine sand and silt. The beautiful Digha sandy beach has appeared as the sea has retreated. The sea has also left behind salt creeks and marshes. There is a belt of dunes at the back.
The sub-Himalayan tract, known as the West Bengal Duars, or Western Duars, is a part of the Tarai lowland belt between the Himalayas and the plain. Once infested with malaria, the area is now well drained and cultivated. Some of the finest tea plantations of India are situated there. North of the Duars, the Himalayan mountain ranges rise abruptly along the northern boundary of the state. Mount Kanchenjunga, actually located in adjacent Sikkim, dominates the landscape of the area, particularly in Darjiling (Darjeeling). On a clear day, Mount Everest also can be seen in the distance. The elevation of the plain increases slowly toward the west; the rise is most marked near the Chota Nagpur plateau of neighbouring Jharkhand.
WBPCS Notes brings Prelims and Mains programs for WBPCS Prelims and WBPCS Mains Exam preparation. Various Programs initiated by WBPCS Notes are as follows:-
- WBPCS Mains Tests and Notes Program
- WBPCS Prelims Exam 2020- Test Series and Notes Program
- WBPCS Prelims and Mains Tests Series and Notes Program
- WBPCS Detailed Complete Prelims Notes