Munger Hilly region is a part of which of the following physiographic region ?

Question

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Correct — B, Southern Hilly Region. Bihar's physiography is conventionally divided into four units, and the Munger hills belong to the last of them. Running north to south these are: the Shivalik or Someshwar hills along the Nepal border in West Champaran; the North Bihar Plain, the alluvial tract between those hills and the Ganga, drained by the Gandak, Burhi Gandak, Bagmati, Kamla and Kosi; the South Bihar Plain, the narrower alluvial belt south of the Ganga carried by the Sone, Punpun, Phalgu and Kiul; and, along the southern margin, the hilly and plateau tract that is the northern fringe of the Chotanagpur plateau. The Munger or Kharagpur hills are part of that southern tract — a block of old crystalline and metamorphic rock rising abruptly above the alluvium in Munger, Jamui and Banka in the east of the state, matched in the west by the Kaimur range in Rohtas and Kaimur and in the middle by the Rajgir and Gaya hills. They are geologically continuous with the ancient peninsular shield rather than with the Ganga's sediment, which is the whole basis of the classification: the two plains are Quaternary alluvium laid down by rivers, while the southern hills are Precambrian rock. Munger district itself sits astride the boundary, with its headquarters on the south bank of the Ganga and its forested hill country to the south, home to the Bhimbandh Wildlife Sanctuary, notified in 1976 and covering about 682 sq km.

Why the other options are wrong — (a) This is the alluvial tract north of the Ganga, between the river and the Nepal border, and it contains no hills at all except the Someshwar range at its far north-western corner. Munger lies south of the Ganga, so it cannot belong to a northern unit.  (c) The genuinely tempting option, and the one on which reference sources actually differ. Munger district straddles the boundary — its plain along the Ganga is South Bihar Plain — and some descriptions treat the Kharagpur hills as residual outcrops standing within that plain rather than as a separate unit. But as a landform the hills are plateau fringe, not plain, and the question asks about the hilly region specifically.  (d) A real range, but at the opposite end of the state. The Someshwar hills are the sub-Himalayan Shivalik ridge in West Champaran on the Nepal frontier, and they carry Bihar's highest point at Someshwar Fort, about 880 m. They lie roughly 300 km north-west of Munger and belong to a completely different geological system.

Concept: Bihar's landscape is the product of two very different geological histories meeting along a line. Everything from the Ganga northwards, and most of the belt immediately south of it, is Quaternary alluvium — some of the deepest and youngest sediment in India, laid down by rivers descending from the Himalaya, which is why north Bihar is so flat and so flood-prone. The southern margin of the state is the other India entirely: the northern edge of the Chotanagpur plateau, Precambrian crystalline rock belonging to the peninsular shield, worn down into low ranges and isolated residual hills. After the reorganisation of 2000, when Jharkhand was created, Bihar retained only this fringe of the plateau, so the 'Southern Hilly Region' of the state's physiography is a thin discontinuous band rather than a broad upland: the Kaimur range in the west, the Rajgir and Gaya hills in the centre, and the Kharagpur hills around Munger in the east.

State PCS 2024 Q98 — Geography PYQ with Answer

State PCS 2024 Q98 — Geography PYQ with Answer