Chapter 2 South Asia
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Chapter 2 South Asia South Asia, corresponding to the Indian sub-con- forms the water-parting between drainage into tinent, has three major physiographic components the Indian ocean and into the deserts of Central based on geologic structure and terrain. These Asia. It is also an important geological link be- are: (1) the Himalayan and associated fold moun- tween the Hercynian Pamir and the Alpine tains, (2) the ancient crystalline block of Penin- Himalaya. sular India, and (3) the alluvial Indo-Gangetic lowland in between the two. The last component The Karakoram Range extends over 350 km in is an extensive plain and lies outside the moun- an east-south-east/west-north-west direction from tain realm. Nevertheless, its genesis owes much the Siachen-Shyok confluence in the south-east to the deposition of materials from the adjoining to the Ishkuman River in the north-west. The high highlands. The vast thickness of its sediments, mountains are bounded by the Indus gorge and up to 6,500 metres along the foothills, is indica- the Ladakh Range to the south, desolate plateau tive of the dynamic processes operating in the to the east, the Aghil Mountains to the north, and Himalayan Mountains. The mountain ranges of the Hindu Kush westwards beyond the Kurumbur the first two physiographic components are River. Structurally, the Karakoram Range is com- grouped into five units: the Karakoram, the posed of three units: the northern sedimentary Himalaya, north-east ranges, peninsular ranges, zone, the central metamorphic zone with a plu- and north-western ranges (Figure 1 and Annex tonic core, and the southern volcanic schist zone. A). They are described in a clock-wise sequence starting from the Karakoram in the extreme north. “Still puzzling, and certainly one of the most fas- cinating future studies, are the connections of the 2.1 The Karakoram N-S-striking Nanga Parbat elements of the Hima- layas with the here almost E-W-striking The name Karakoram (black gravel or stone) is Karakoram” (Gansser 1964, p38). derived from the Karakoram Pass (5,570m) which does not even cross the main range but lies fur- Such geological complexity is matched by ex- ther east. Although the crest zone of the Great treme relief as the Karakoram Range has the Karakoram is conventionally so called, the indi- greatest assemblage of giant peaks, with 33 over vidual sections of high mountains are known as 7,325m, among which is K-2/Godwin Austin muztagh (ice mountain). The Karakoram Range (8,611m). The area is the most heavily glaciated 5 Mountains of Asia 6 Figure 1: South Asia Author 2. Karakoram Landscape, Pakistan. Section of Indus River and Karakoram Highway, south of Gilgit. Hamlets are spread on two levels of talus terraces irrigated by long channels from tributary streams. The lowest terrace beside the Indus has an army camp for road maintainance. outside sub-polar latitudes: 28 to 50 per cent ralism is difficult. In the past, the remote valleys compared to eight to 12 per cent for the Himala- of the Karakoram provided a passage for hardy yas and 2.2 per cent for the Alps. Therefore, it traders and pilgrims across domains of feuding contains some of the longest glaciers outside sub- chieftains. Their turbulence has since been re- polar regions. placed by major rivalries between India and Pa- kistan in Kashmir, and China and India in Aksai Much of the area is wild and rugged. Westwards, Chin. These military conflicts have opened up in Gilgit and Hunza, settlements are located on the area with stupendous roads, such as the river terraces and hanging valleys at elevations 753km Karakoram Highway, that also sustain the ranging between 1,850m and 2,200m (Plate 2). local economies through providing access to Higher up, pastures extend from 2,000m to markets. 3,500m. Tiny fields and orchards are irrigated by elaborate channels of melt-water. Some Hunzakut 2.2 The Himalaya terms for varied land use are bassikish (orchard), harkish (cultivated land), ter (high pasture), and The word Himalaya is a compound of Sanskrit tog (irrigated meadow)). Two-thirds of the popu- words, hima for snow and alaya for abode, refer- lation of Hunza is Burusho, the rest being Wakhi ring to the lofty range between the Indo-Gangetic (19%) and Shinaki (13%) and a minority of Dom plain and the Tibetan plateau. It extends nearly (1.1%) (Kreutzmann 1993). Originally a Shiite 2,400 km in a vast southerly arc between the bend island in Sunni Pakistan, the area has become a of the Indus marked by Nanga Parbat (8,125m) stronghold of the Ismailiya faith. Fruit cultivation on the west to the Brahmaputra bend around is of the utmost importance in these valleys. In Namcha Barwa (7,755m) in the east. The Hima- Baltistan, further east, barley cultivation depends layan Range is the loftiest mountain complex on on the snow. The hot summer enables the culti- earth with 31 peaks exceeding 7,600m in height. vation of a wide variety of fruit species. Aksai The extreme elevation and rugged relief are the Chin, the northern glacis of the Karakoram itself, result of rapid mountain-building forces and vig- merges into a harsh plateau where even pasto- orous erosion processes. Therefore, the Hima- 7 A Regional Inventory Mountains of Asia 8 layan chains are not massive elevations but nar- some sedimentary remnants on the summits. row ridges. In places, they are traversed by ex- Apart from at river gorges and some passes, the tremely deep river gorges resulting in great verti- crest of the Great Himalaya rarely falls below cal contrasts over very short horizontal distances. 5,500m.Between the Indus and the Brahmaputra, the main range has been breached by four rivers The Himalayan Range is a singular entity of im- only: the Sutlej, the Karnali, the Kali Gandaki, mense physical dimension. Therefore, the use of and the Arun. its plural form, Himalayas, in geological and geo- graphic context. The former pertains to the north- The above three-fold geological division of the south transverse section of structural formation Himalaya has a general consensus. In contrast, while the latter refers to the east-west longitudi- the division of the Himalaya into east-west sec- nal sections of regional units.The well-recognised tions is much at variance, according to authority geological units rising in echelon from the south and approach. Although most delimitations are to north are the Siwalik, the Lesser Himalaya, based on major rivers and political units, the and the Great Himalaya. The Siwalik Range, also number of sections range from Burrard’s four to called the sub-Himalaya, is the youngest of all, Bose’s nine (Table 2). A standard survey on and abuts the plains as foothills dipping to the Himalayan exploration recognised five sections north. It extends from the Indus almost to the (Mason 1955). These were (1) the Punjab Brahmaputra with one gap of over 300 km from Himalaya between the Indus and Sutlej rivers, the Sapta Kosi to the Manas River where the fierce (2) the Kumaon Himalaya between the Sutlej and monsoon erosion has almost worn it away com- Mahakali-Sarda rivers, (3) the Nepal Himalaya pletely. The second, the Lesser Himalaya, is older with three sub-sections between the Mahakali- and higher than the Siwalik Range, but with the Sarda River and Singalila ridge, (4) the Sikkim same strike alignment. The structure is more com- Himalaya corresponding to the Tista basin, and plex, being contorted by uplift into recumbent (5) the Assam Himalaya, east of Sikkim to the folds with older sedimentaries overthrusting Brahmaputra-Dihang. Another authoritative re- younger ones. The Great Himalaya, the axis and gional study on the Indian sub-continent pro- crystalline core of the whole range, is composed posed eight sections (Spate 1957). It further des- mainly of intruded granites and gneisses with ignated Kashmir and the Karakoram as western; Author 3. Gurung Village, Nepal. Naiche (1,402m) is a compact village of 54 houses perched on a ridge to save level ground for fields. The economy is based on maize and paddy cultivation along with sheep herding. Most households have a member serving in a foreign army. Table 2: Sections of the Himalayan Range Source Western Central Eastern No. Bose Himachal Uttarakh Jammu & Kashmir Ghagra Gandak Kosi Sikkim Bhutan Assam 9 (1972) Pradesh and Gansser Punjab Kumaon Nepal Sikkim/Bhutan NEFA 5 (1964) Spate Karakora Himachal Kashmir Kumaon Nepal Kosi Sikkim Bhutan/Assam 8 (1957) m Pradesh Mason Nepal Karakoram & Punjab Kumaon Sikkim Assam 5 (1955) Karnali Gandaki Kosi Burrard 9 Punjab Kumaon Nepal Assam 4 (1907) Km 0 870 1,670 2,470 Section Boundary A RegionalInventory Primary Secondary Tertiary Mountains of Asia 10 Rana Madhukar 4. Traditional Bhutanese Dance Himachal Pradesh, Kumaon, and most of Nepal Rao 1986), practice seasonal transhumance (Box as central; and east Nepal, Sikkim, Bhutan, and 1). Forest resources also become important. Cul- the NEFA as the eastern Himalaya. A more logi- turally, Himachal Pradesh and Uttarakhand are cal division seems to be that of Bose (1972) which decidedly Hindu in contrast to the predominance has nine sections (Table 2) grouped into three of Islam in Kashmir and Buddhism in Ladakh. primary divisions, each with three secondary sec- tions. Thus, (a)the Western Himalaya includes The Central Himalaya, extending 800 km from Jammu & Kashmir, Himachal Pradesh, and the Mahakali-Sarda to the Mechi rivers, corre- Uttarakhand; (b) the Central Himalaya includes sponds to the longitudinal extension of Nepal the Ghagra (Karnali), Gandak, and Kosi basins encompassing the Karnali, Gandaki, and Kosi of Nepal; and (c) the Eastern Himalaya, the sec- basins.