{{short description|Mountain range in India, Pakistan and Nepal}} {{Use dmy dates|date=October 2019}} {{Use Indian English|date=October 2019}} {{Infobox mountain |name=Sivalik Hills |image=Ganges_and_the_Shivalik_ranges,_near_Rishikesh.jpg |image_caption=Sivalik Hills and Ganges River |image_map=Sivallik Hills map.svg |image_map_caption=Sivalik Hills, highlighted in light red |range_coordinates={{coord|27|46|N|82|24|E|source:kolossus-fiwiki|display=inline,title}} |length_km=2400 |location=northern Indian subcontinent |parent=outer Himalayas |geology=Tertiary }} The '''Sivalik Hills''', also known as '''Churia Hills''', are a mountain range of the outer Himalayas. The literal translation of "Sivalik" is 'tresses of Shiva'.<ref name=Balokhra99>{{cite book |last1=Balokhra |first1=J. M. |year=1999 |title=The Wonderland of Himachal Pradesh |publisher=H. G. Publications |location=New Delhi |edition=Revised and enlarged fourth |isbn=978-81-8465-975-7}}</ref> The hills are known for their numerous fossils, and are also home to the Soanian Middle Paleolithic archaeological culture.<ref name=SchugWalimbe2016/>
== Geography== The Sivalik Hills are a mountain range of the outer Himalayas that stretches over about {{cvt|2400|km}} from the Indus River eastwards close to the Brahmaputra River; they are {{cvt|10|-|50|km}} wide with an average elevation of {{cvt|1500|-|2000|m}}. Between the Teesta and Raidāk Rivers is a gap of about {{cvt|90|km}}.<ref name=Kohli2002>{{cite book |author=Kohli, M. S. |title=Mountains of India: Tourism, Adventure and Pilgrimage |year=2002 |chapter=Shivalik Range |pages=24–25 |chapter-url=https://books.google.com/books?id=GIs4zv17HHwC&pg=PA24 |publisher=Indus Publishing |isbn=978-81-7387-135-1}}</ref> They are known for their Neogene and Pleistocene aged vertebrate fossils.<ref>{{Cite journal |last=Kaur |first=A. P. |date=2022 |title=New fossil mammalian assemblages and first record of ostrich from the Pinjore (Pinjor) formation (2.58–0.63 Ma) of Siwalik Hills near Chandigarh, northern India |journal=Quaternary Science Reviews |volume=293 |article-number=107694 |doi=10.1016/j.quascirev.2022.107694 |bibcode=2022QSRv..29307694K}}</ref>
==Geology== Geologically, the Sivalik Hills belong to the Tertiary deposits of the outer Himalayas.<ref name=EB1911>{{cite EB1911 |wstitle=Siwalik Hills |volume=25 |pages=163–164}}</ref> They are chiefly composed of sandstone and conglomerate rock formations, which are the solidified detritus of the Himalayas<ref name=EB1911/> to their north; they are poorly consolidated. The sedimentary rocks comprising the hills are believed to be 16–5.2 million years old.<ref>{{cite journal |last1=Gautam |first1=P. |last2=Fujiwara |first2=Y. |year=2000 |title=Magnetic polarity stratigraphy of Siwalik Group sediments of Karnali River section in western Nepal |journal=Geophysical Journal International |volume=142 |issue=3 |pages=812–824 |doi=10.1046/j.1365-246x.2000.00185.x |bibcode=2000GeoJI.142..812G |doi-access=free|hdl=2115/38248 |hdl-access=free}}</ref>
They are bounded on the south by a fault system called the Main Frontal Thrust, with steeper slopes on that side. Below this, the coarse alluvial Bhabar zone makes the transition to the nearly level plains. Rainfall, especially during the summer monsoon, percolates into the Bhabar, then is forced to the surface by finer alluvial layers below it in a zone of springs and marshes along the northern edge of the Terai or plains.<ref name=Mani>{{cite book|title=Ecology and Biogeography in India|first=M.S.|last=Mani|publisher=Springer Science & Business Media |year=2012 |page=690}}</ref>
== Prehistory == {{see|South Asian Stone Age#Siwalik Hills}} [[File:Colossochelys atlas.jpg|thumb|right|Skeleton of the gigantic tortoise ''Megalochelys atlas'', the largest known to have ever existed, and one of the best known Sivalik fossils]] The Sivalik Hills are well known for fossils of vertebrates, spanning from the Early Miocene, until the Middle Pleistocene, around 18 million to 600,000 years ago.<ref>{{Cite journal |last=Nanda |first=A.C. |date=2002 |title=Upper Siwalik mammalian faunas of India and associated events |journal=Journal of Asian Earth Sciences |volume=21 |issue=1 |pages=47–58 |doi=10.1016/S1367-9120(02)00013-5|bibcode=2002JAESc..21...47N }}</ref><ref>{{Cite book |last=Patnaik |first=R. |chapter=Indian Neogene Siwalik Mammalian Biostratigraphy. An Overview |date=2013 |doi=10.7312/wang15012-017 |title=Fossil Mammals of Asia |place=New York Chichester, West Sussex |publisher=Columbia University Press}}</ref>
Some of the best known fossils from the hills include ''Megalochelys atlas'', the largest known tortoise to have ever existed,<ref name="TEWG2015">{{cite journal |author1=Rhodin, A.G.J. |author2=Thomson, S. |author3=Georgalis, G. |author4=Karl, H.-V. |author5=Danilov, I.G. |author6=Takahashi, A. |author7=de la Fuente, M.S. |author8=Bourque, J.R. |author9=Delfino M. |author10=Bour, R. |author11=Iverson, J.B. |author12=Shaffer, H.B. |author13=van Dijk, P.P. |year=2015 |title=Turtles and tortoises of the world during the rise and global spread of humanity: first checklist and review of extinct Pleistocene and Holocene chelonians. |journal=Chelonian Research Monographs |volume=5 |issue=8 |pages=000e.1–66 |doi=10.3854/crm.5.000e.fossil.checklist.v1.2015 |doi-access=free |hdl-access=free |collaboration=Turtle Extinctions Working Group |hdl=11336/62240}}</ref> the sabertooth cat ''Megantereon falconeri'',''<ref name=":2">{{Cite journal |last=Stimpson |first=Christopher M. |date=May 2024 |title=Siwalik sabrecats: review and revised diagnosis of Megantereon fossils from the foothills of the Himalaya |journal=Royal Society Open Science |language=en |volume=11 |issue=5 |bibcode=2024RSOS...1131788S |doi=10.1098/rsos.231788 |doi-access=free|issn=2054-5703 |pmc=11076117 |pmid=38720790}}</ref>'' ''Sivatherium giganteum,'' the largest known giraffid,<ref name=":0">{{cite journal |last1=Basu |first1=Christopher |last2=Falkingham |first2=Peter L. |last3=Hutchinson |first3=John R. |date=January 2016 |title=The extinct, giant giraffid ''Sivatherium giganteum'': skeletal reconstruction and body mass estimation |journal=Biology Letters |volume=12 |issue=1 |article-number=20150940 |doi=10.1098/rsbl.2015.0940 |pmc=4785933 |pmid=26763212}}</ref> and the ape ''Sivapithecus''.<ref>{{cite journal |last1=Kelley |first1=J. |date=1988 |title=A new large species of Sivapithecus from the Siwaliks of Pakistan |journal=Journal of Human Evolution |volume=17 |issue=3 |pages=305–324 |doi=10.1016/0047-2484(88)90073-5|bibcode=1988JHumE..17..305K }}</ref>
Remains of the Lower-Middle Paleolithic Soanian culture dating to around 500,000 to 125,000 years Before Present were found in the Sivalik region.<ref>{{cite journal |title=Is the Soanian techno-complex a Mode 1 or Mode 3 phenomenon? A morphometric assessment |journal=Journal of Archaeological Science |volume=34 |issue=9 |pages=1434–1440 |doi=10.1016/j.jas.2006.11.001|year=2007|last1=Lycett|first1=S. J.|bibcode=2007JArSc..34.1434L }}</ref> Contemporary to the Acheulean, the Soanian culture is named after the Soan Valley in the Sivalik Hills of Pakistan. The Soanian archaeological culture is found across Sivalik region in present-day India, Nepal and Pakistan.<ref name="SchugWalimbe2016">{{cite book|editor1=Schug, G. R. |editor2=Walimbe, S. R. |title=A Companion to South Asia in the Past |date=2016 |publisher=John Wiley & Sons |location=Oxford, Chichester |isbn=978-1-119-05547-1 |author=Chauhan, P. |chapter=A decade of paleoanthropology in the Indian Subcontinent. The Soanian industry reassessed |page=39 |chapter-url=https://books.google.com/books?id=7xv-CwAAQBAJ&pg=PA39}}</ref>
==Ecosystem== The carbon stock and carbon sequestration rates of the Churia forests differ among different forest management regimes and are highest in protected areas.<ref>{{Cite book |last1=Thapa |first1=H. B. |title=Churia forests of Nepal |url=http://www.dfrs.gov.np/downloadfile/CHURE_REPORT_1453193322.pdf |archive-date=2017-05-08 |archive-url=https://web.archive.org/web/20170508190912/http://www.dfrs.gov.np/downloadfile/CHURE_REPORT_1453193322.pdf |publisher=Forest Resource Assessment Nepal, Department of Forest Research and Survey, Ministry of Forests and Soil Conservation, Government of Nepal |date=2014 |lccn=2015515752}}</ref><ref>{{Cite journal |last1=Subedi |first1=B. |last2=Lamichhane |first2=P. |last3=Magar |first3=L. K. |last4=Subedi |first4=T. |date=2022 |title=Aboveground carbon stocks and sequestration rates of forests under different management regimes in Churia region of Nepal |url=https://www.nepjol.info/index.php/BANKO/article/view/45442 |journal=Banko Janakari |volume=32 |issue=1 |pages=15–24 |doi=10.3126/banko.v32i1.45442|doi-access=free }}</ref> Early twentieth-century engineering studies of the Punjab Himalaya and adjoining Siwalik Hills provided some of the earliest documented recognition of the environmental consequences of deforestation in the region. Work by L. B. Holland and H. M. Glover (1930) explicitly linked the disappearance of forests in the outer Himalaya to increased surface runoff, soil erosion, reduced groundwater retention, and more frequent and severe flooding, noting that formerly forested catchments had become degraded, sediment-laden, and less capable of sustaining stable water supplies.<ref>Holland, L. B.; Glover, H. M. (1930). ''Erosion in the Punjab Himalaya and its probable effect on water supplies''. Proceedings of the 18th Annual Congress of the Irrigation Branch, Buildings and Roads Branch, and Railway Branch North West Railway (Pakistan Engineering Congress). https://pecongress.org.pk/wp-content/uploads/2024/06/P18-PAPER135.pdf</ref><ref>Vardon, J. (1930). ''Some Interesting Tube Wells on the North Western Railway''. In: Proceedings of the 18th Annual Congress of the Irrigation Branch, Buildings and Roads Branch, and Railway Branch NWR (Pakistan Engineering Congress). https://pecongress.org.pk/wp-content/uploads/2024/06/P18-PAPER139.pdf </ref>
==See also== thumb|upright|Ganga river cutting through the Sivalik hills <!-- Please help by converting this to an "Outline" article and/or create/add to a navigation template. --> ; Subranges of Sivalik * Dundwa Range * Margalla Hills * Shivalik Fossil Park ; Geological subdivisions of Himalayas * Indus-Yarlung suture zone *Karakoram fault system *Nyenchen Tanglha Mountains *Main Himalayan Thrust * Lower Himalayan Range ; Geographical subdivisions of Himalayas * Western Himalayas * Eastern Himalayas * Indian Himalayan Region, Geology of Bhutan and Geology of Nepal * Jammu and Kashmir (union territory), Geography of Ladakh, Gilgit-Baltistan and Geology of Pakistan
==References== {{Reflist}}
{{GeoSouthAsia}} {{Himalayas}} {{Sister bar|auto=1|s=1911 Encyclopædia Britannica/Siwalik Hills}} {{Authority control}}
Category:Mountain ranges of the Himalayas Category:Mountain ranges of Asia Category:Mountain ranges of Bhutan Category:Mountain ranges of India Category:Mountain ranges of Nepal Category:Mountain ranges of Pakistan Category:Hills of Jammu and Kashmir Category:Hills of Uttarakhand Category:Hills of Himachal Pradesh Category:Hills of Sikkim Category:Himalayan subtropical broadleaf forests