Chapter Iii Topography
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CHAPTER III TOPOGRAPHY MAP-1 36 ·lAP OF 3 'I I ,,.-, I -... , ', .~ ... ' -- .... ',, :......... : ' .... 26 '\ \. \ \) ' ... , \ ,; ....... ,. , ,,. , , __ ,~ I / I I N 2 ,.-- ... I,,. I _. '/ I ,'~.1' ',, I ~",, '.: ... ..,. 1 I ' I I I I ' '·, \·iE:3T.8RN GEATS '2- iVJ.AHARASHTRA 8 DISTRICT 76 Bo 84 88 92.. MAHARASHTRA STATE NAP - 2 76. 78. 80. 17-'t: ...\ r-. /'.... .~' . -·, ,-· ~--._,. \ l /' .... -· . > .. · • ~' . •,..... • ..... ,I " .__. ' . '•.., ,. .,..._ ' .,. .J '·- ·-·..' . ...: • ;· -· r·-·-·-·., 1 ..... \ ···· .. ., / ·.,..... •. ... ., : · ~· ..... ~. ·...... ... · .. ·. ... ' "' .. ., ' .\:;·· ... : ,:._ .. ·, L.,_.~.-::·· ....'J··,···;}l ·~· ., ___ .., .. :·····. .. ) ! , ·"'-~~ : ...... .·· .. · •...... :. ,.I'\.•·:· ~ I •"•.:"": :.... -;·.· .J ..::- ·- -~ ··.. :· .. ·· ... ...i , co-'' o . ··:>··"·:\... (~~ '"- '.. -~: ··.-.:.·.·· " ·· .. ···'! . .•• c:1\ : I ·-·':. .· ··.-· · ·.:') . ~i PUNE ·. :" ·. c:1 •· .• :,· j .,.\ 0 ... a: ·-·=·:.... ... ....... ~- ···:.. _::~=· .. ··. .J ..... { ··...... ,-4~ :.. SHOLAPUR <' ..~ , __ , ~ .· \ ·J·---., ~ !... ... ........,_,· .. ....···c· . % SANGLI '"' ..... "') '4-.:" ......... ·.. ,.) •J tN a: .~ ·.... ···~.: / .....} ..... l ':1 I :::.~. ·-.J '·. } 0 100 200 km ( . ' 74·--h,"' ·-· 76. 7!. .-~ SELECTED COLLECTION LOCALITIES 1 • Mahabaleshwar 24. Yavteshwar 46. Kolewadi 2. Pratapgad 25. Dhavadi 47. Nandgaon 3. Panchgani 26. Mahuli 4£L Yelgaon 4. ~·~edha 27. Borgaon 4.9. Masur 5. Bam noli 23. Viai 50. Chorjwadi 6. Kas 29. Kenjalgad 51 • Khatav 7. Kelghar ghat 30. Kamalgad 52. Lalgun 8. Kudal 31 . Dhom dam 53. Budh 9. Vasota 32. Pandavgad 54. Aundh 10. Pat an 33. Kumbharli ghat 55. Nimsod 11. Devgad 34. Shirgaon gha! 56. Vaduj 1 2. Kumbharli ghat 3 5. Chandan-vandan 57. Dahivadi fort 1 3. i'l'!irgaon 58. ?ingli tank 36. Khandala 14. Rasati 59. rr.al vadi 37. Lonand 1 5. Horgiri 60. :~ograla ghat 38. Koregaon 16. Salve 61 . Mardi 39. Sols hi 17. Sanbur 62. Mhasvad 40. ?impoda 18. Dhebewadi 63. ?halt an 41 . Wathar 19. Chaphal 64. Tathavada 42. Kinhai 20. Tarle 65. Vathar 43. Vardhangad 21 • Sa tara 66. ~/idni 44. Karad -'2. Asangaon 67. Nimblak 45. Kole 23. Kanher 68. Javali MAP- 3 N SATARA DISTRICT PUNE 10 Km t •6t • 57 ii (E <:f :;: 1- <:f 12: ,.......- MAP- 4 '' SATARA DISTRICT ~ FOREST AREAS v D <:::> "< ..... ~ '? .._ ,..... Q ,____.....10 Km U' .S<:ALL+ '< (t 0 d ? Vl C::?c:3 ~ 0 'i):,~ lfl c3 c::: 0 Q C) " 4 "7- s ' · ,..... 4. 0 ~~CE- roRE sr ARE• ~ c= - OI SHtiCf 80VN0Aif'r ·-- tAlU~• BCIJNOArn -- WATION4l HIGHWAY' :><::. ROAD ( MOfORA8lE ) - RAilWAY ' ~ RIV(R ~ OA~ OR fAH( s -- bOUN()AH"t' 0( Wt~1[RN CH+/ .i MAP- 5 SATARA DISTRICT ANNUAL AVERAGE RAINFALL I 10 Km I OVER 600 em ~ 200-150 l!3 250-200 §3150-75 D BELOW 75 xiii Topography There is a marked difference in the general topo graphic features of the area. The main range of the Sahyadri stretching about 100 km from North to South forms the Western boundary of the tract. The Mahadeo range ori ginates from the Sahyadrian complex about 16 km north of Mahabaleshwar and stretches east and south-east across the whole breadth of the district. These two ranges form the major hill conplex of the tract. Within the limits of the tract, the crest of Sahysdris is crowned by several peaks. The main line of the Sahyadris develops into several coles and saddles of which the more accessible ones have become major ghat routes. Besides many small saddles, the Mahadeo range is crossed by three important passes, the Khambatki pass and two breaks near Tadvala about 19 km north-east of Khambatki. The tops of the ma.in Sahyadris and of the rttahadeo hills especially in the north-western tracts of Wai, Jaoli and Paten look like a succession of fortresses raised on a series of plateaus ?iled on over the other, the whole surmounted·by a wall of rock. The top of Mahabaleshwar, the highest point in the tract is about 1,436 m above the mean sea level. From the high Deccan tableland on the east, the Sahyadris seem somewhat low and tame but from the western en~e of their crest great forms stand out xiv from the Konkan with bold wild outlines and cliffs which in places have a shear drop of over 910 metres. For about 48 km after leaving the Sahyadris, the Mahadeo hills keep a height of about 1,220 m above the mean sea level and about 610 m above the plains. The north face of the Mahadeo range fall~ shArply into the Nira valley to the south. The hill falls much more gently into the valley of the Krishna. Some notable hills which add to the relict of Satara district are- Sonjai (1,003 m), Vsrdhangad (1 .'167 m), Pandavgad (1,273 rn), Ke.njalgad (1,301 m), Vasota (1,302 m) and Kamalgsd (1,375). Drainage The area is drained by four major rivers viz., the Nira in the entire Northern belt, the Man in the East and the Yerla and the Krishna in the South. The Kri ~hn a is one of the three sacred rivers of southern India. It rises on the eastern brow of the Mahabaleshwar plateau six km west of Jor in the extreme west of Wai. Like Godavari and Kaveri, it flows across almost the entire breadth of the peninsula from west to east and flows into the Bay of Bengal. Out of its total length of 1,280 krn, about 176 km lie within Satara district. The Kudali, Urmodi, Tsrli and Vasna are the small feeders of Venna or Yenna, Koyna and Yerla are the chief feeders of Krishna river. XV Today Y ~ yn8 hJs become the most important river in Maharashtra on account of the hydro-electric project · developed at Koyna nagar near Helwak. The river Nira has acquired economic importance on account of the Bhatgar and the Vir dams supporting an extensive network of canals for irrigation. Geology : The district is covered by basaltic lava flows of upper cretnceous - lower eocene age. The basalts are capped by lc?- :-,r rite, found in the plateus about 900 m mean sea level. Along the sources of the major rivers, alluvium has '-H~en deposited in recent times. Deccan Trap The basalt flows of the area are of two types. The :3.:1 flow, which as common, shows a basal section having chilled basalt or greyish clinker which shows frc.gments of highly vesicular or dense purple trap cemented by zeolites or secondary silica or glass. The middle section of the flow comprises dark or dark grey, dense basalt. Over this is found a section of flow breccia which also consists of sub-rounded to angular blocks of ve [' ~ cular trap cemented by zeolites, glass and pulverised r ···-k . The top-most layer is pinkish or purplish glass which at places gives rise to clay-like material after weathering. The product of weathering comprises fine fragments and gives rise to smooth slopes. Owing to this differe n~ e in weathering characters, cliffs, benches xvi and terraces are formed. In addition wide plateaus of plains are also formed. Broad bottomed valleys are derived wherever the er6sion is arrested by the dense sections of the flows. Amphitheatre-like geomorphological features are also conspicuous in these areas. Dyke : Dykes ere rare. The rock of the dyke is similar to that of porphyritic basalt. Laterite Laterite occurs on the plateau tops as tabular masses. It is well exposed in the Panchgani-Mahabaleshwar plateaus and in the plateaus on either side of Koyna river. In Mahabaleshwar area, the laterite is seen from 1370 m to 1440 m and ~~ain around 1290 m indicating two levels. In the area south of Panchg.:mi the level falls from 1265 rn in the north t0 1045 m in the south near Koyna dam. Alluvium : Occ,,rs in patches alon.~ banks of rivers like the Krishna, Venna, Kudali, Koyna and others. It consists of beds of pebbles and boulders of trap and chert, silt and sand. Soil : The breccia portion of aa flows and the pahoehoe flows give rise to purplish or reddish soil mixed with grains of zeolite, chert and quartz, etc. The dense sections of the flows give rise to dark clayey soil. In the western pert, where the laterite is extensively eroded the reddish brown soil is conspicuous. xvii Economic rocks end runerals Bauxite : Bauxite occurs in the laterite plateaus nea~ ?anchgani and at a few places in the east Koyna valley. It occurs as large lenses or pockets and shows variation in thickness. Construction material : The dense section of flows yield tough rock suitable for road making and as railway ballasts and concrete aggregate. Kanker : Alo~ the courses of streams and in alluvial patches, kankar and calc-tufa occur as irregular patches. These are excavated and used locally for making lime. Groundwater : The alluvial patches are good aquifers. Wherever the trap rocks are weathered, the joints and fractures become open and help in groundwater movement. Laterite, which is full of voids, helps in seepage of rain water and such weter comes out as springs along the litho margie clay contact. Several such springs are the sources of domestic and to some extent, agriculturel needs of many villages, at higher levels in the east Koyna valley. Climate The climate can be broadly divided into four seasons viz., the cold, the hot, the south-west monsoon and the post monsoon seasons. The cold season starts by about the end of November and continues upto middle of February. It is followed by hot season from the middle xviii of February till the on-set of the monsoon in the first or second week of June. The south-west monsoon is from June to September. The post monsoon months are October and November. Rainfall : (Map 5 .) Considering the district as a whole excluding the n~rrow strip along the western border which gets heavier rainfall, the major part lies in the rc:in shadow areas and variation in the annual rainfall is large.