INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 1, No 4, 2011

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1 Morphometric analysis of Gundal watershed, Gundlupet taluk, Chamarajanagar district, Karnataka, India Lakshmamma 1, Nagaraju.D 1, Mahadevaswamy.G 1, Siddalingamurthy.S 1, Manjunatha.S 2 1- Department of Studies in Earth Science, Manasagangothri Mysore, Karnataka, India 2- Department of Geology, Karnatak Science College, Dhrawad. ABSTRACT Morphometric analysis was done to determine the drainage characteristics of gundal watershed using topographic maps. This watershed divided into 25 sub watersheds. The drainage patterns of the sub-basins are dendritic and parallel, the basin includes heist order 4 is role stream and the area covers 79sqkm. The analysis clearly indicates some relations among the various attributes of the morphometric aspects of the watershed and helps to understand their role in sculpturing the surface of the region. Keywords: Sub watershed, Drainage patterns, dendritic, stream patterns sculpturing. 1. Introduction Morphometry is the measurement and mathematical analysis of the configuration of the earth s surface, shape and dimension of its landforms (Clarke, 1966). The quantitative analysis of drainage system is an important aspect of characteristic of watershed (Strahler, 1964). The morphometric study of the drainage basin is aimed to acquire accurate data of measurable features of stream network of the drainage basin. Drainage provides a basic to understand initial slope, inequalities in rock hardness, structural control, geological and geomorphologic history of the drainage basin. 1.1 Aim and Objectives The following are the major objectives 1. To understand the various attributes data required for planning using thematic maps viz., land use, land cover, soil type, geomorphology, geology, topographic maps, stream network and surface water of the area. 2. To identify major and minor structural features using remotely sensed database followed by ground truth verification. 3. Understanding the morphometric behavior of the area 1.2 Study area The Study area is located lies between latitude 11 41'" to 11 51'15" N and longitude 76 3'45 to 76 51'15" E falling in Survey of India toposheets Nos.58A/9, 58A/1, 58A/13, and 58A/14 on 758

2 1:5, scale. The climate of the area is semi-arid. April is the hottest month in the year with mean temperature of 34.6 C and January and December are the coldest months, the average rainfall is mm which is shown in figure Geology and soil of the area Figure 1: Location of the study area Geographically the taluk is covered by the rocks of Archean age i.e., granite, gneiss and schistose rock. The entire Gundlupet taluk comprises Granitic gneiss having the strike NNE and SSW direction. They comprise essentially gray to pink granite gneisses and the strike of lineation in gneisses is NW-SE with dip towards NE and the schistose rocks are seen on the north/south direction. The rocks are coarse to medium grained. The grey gneisses are highly weathered, fractured and fissured up to an average depth of 8-1 m noticed near Bandipura, Chikkati, (Plate 1&2). The highly weathered Granite exposures were seen in the villages of Madahalli, Somahalli, Gundlupet, Seegavadi and Madapatna. The quartzite and banded iron formations were seen near Channamallipura and Sriramgudda near Gundlupet respectively (Plate 3&4). Dolerite dykes and quartz viens are common with variable strike directions and width. They are found in the village limits of Bandipur, Veeranapura and shivapura village. They have a variable width of 5 to 15 m and extend over a distance of 2 to 3 kms. These intrusions have a bearing on the movement of 759

3 groundwater and whenever these intrusions are encountered a detail investigation about their extent and altitude is considered to identify the water bearing and non water bearing horizons. (Fig.2) GEOLOGY OF THE STUDY AREA 76 3'45" 76 41'" 76 51'15" N W E S 11 51'15" 11 51'15" Legend Plutonic rocks Amphibolites Migmatities 11 41'" 11 41'" 1 Kilometers 76 3'45" 76 41'" 76 51'15" Figure 2: Geology of the area Plate 1: Exposure of Gneiss near Bandipura Plate 2: Weathered Gneisses near Chikkati 76

4 Plate 3: Quartzite exposure near Channamallipur Plate 4: Banded Iron formation near Sriragudda near Gundlupet The major rock types of the area are Gneiss, Charnockite, Felsite porphyrities, Dolerite/Gabbro dykes, Granodiorite, Tonalite and Migmatitie gneiss, banded iron formation metapelites (Staurolite-Kyanite-Siliminite Schist), Amphibolites and hornblende Schist, Meta-ultra mafics, metapyroxinite, serpentinised Dunite and Peridotite, Gneisses, Amphibolite, Schists with intrusion of dykes with a mantle of different types of soils, which is the resultant of the weathering of these rocks, which play a significant role in the geomorphological units. Soil is a main component of land system, which provides a medium for water movement and plant growth. The recharge capacity and groundwater quality is decided by the soil types and their texture. Four types of soils exists in the study area such as Red sandy soil, Red loamy soil, deep black soil and Red gravely soil. (Figure 3). 761

5 Clayey Soil: Forms the major types of soils and occupies the largest area in the NW and Southern part of the Gundlupet taluk. These soils contain larger mixture of sand particles. The thickness varies from meters. SOIL TYPE OF THE STUDY AREA 76 3'45" 76 41'" 76 51'15" N W E S 11 51'15" 11 51'15" Legend Clayey Clayey Mixed Clayey-skeletal Loamy-Skeletal Rocky land 11 41'" 11 41'" 9 Kilometers 76 3'45" 76 41'" Figure 3: Soil of the area 76 51'15" Clayey Mixed Soil: Develops under monsoonic medium dry climate over acid to intermediate parent rock. Red, a Reddish brown and deep yellowish brown soil in the area occupies the eastern and western part of the study area. The thickness varies from mts and also could be classified into deep, medium and shallow types based on colour and texture. Clayey Skeletal Soil: Mostly occupies the central part of the study area. These soils are clayey highly porous with rich plasticity and the base in saturated with Ca and Mg. These have a variable thickness between mts. Infiltration capacity of these soils is very high in the beginning and drastically gets reduced with increasing time. Loamy Skeletal Soil: Forms the northern part of the study area. The soil thickness is 1 cms and the infiltration rate is cm/hrs. 2. Methodology Basin wise morphometric analysis has alternated the attention and is still being used for deriving sensible conclusions regarding a particular behavior of any hydro geological study and 762

6 evaluation of water resources. The morphometric parameters have been considered for analysis are summarized in detail in Table.2 3. Results and Discussion Based on geomorphology and surface water divided marks the highest evaluation on the area. for detailed qualitative analysis have been done and the study area is divided into 25 sub-watersheds (Fig.5) and it is a natural hydrological entity from which surface runoff flows to a defined drains, channel, stream or river of a particular point (Fig.4) The sub-watersheds have been named based on the tank and villages at the outlet this analysis can be achieved through measurement of linear, aerial and relief aspects of the basin and slope contributions. In the present study, the morphometric analysis for the parameters namely stream order, stream length, bifurcation ratios, stream frequency, elongation ratio, circularity ratio, form factor, relief ratio etc., have been carried out using the mathematical formulae (Table.1 and results Table.2). DRAINAGE MAP N Ponds Drainage Gundal area W S E 6 Kilometers 3.1. Linear Aspects Figure 4: Drainage of the Watershed Stream order, stream length, mean stream length, stream length ratio and bifurcation ratio. 763

7 3.1.1 Stream order The primary step in any drainage basin analysis is order designation, stream orders and is based on a hierarchic ranking of streams. Ranking of streams has been carried out based on the method proposed by strahler (1964) (Table 1). It is observed that the maximum frequency is in the case of first order streams. It is also noticed that there is a decrease in stream frequency as the stream order increases Stream Length: Stream length is one of the most important hydrological feature of the basin as it reveals that the surface run-off behaviours, The number of streams of various orders in a sub-watershed is counted and their lengths from mouth to drainage divide are measured. The stream length (Lu) has been computed based on the low proposed by Horton (1945) for all the 25 sub-watersheds. Generally the total length of stream segments in maximum is first order streams and decreases as the stream order increases Mean Stream Length: The mean stream length is a dimensionless property, characterizing the size aspects of drainage network and its associated surface (Strahler, 1964). It is obtained by dividing the total length of stream of a order by total number of segments in the order (Table 1). In the study area the mean stream length varies from.99 to 12.1 and mean stream length of any given order is greater than that of the lower order and less than of its next higher order in the entire sub watersheds except which might be due to variation in slope and topography Stream Length Ratio: it is the ratio between the mean lengths of streams of any two consecutive orders. Horton s law (1945) of stream length states that the mean length of stream segments of each of the successive orders of a basin tends to approximate a direct geometric series, with stream lengths increasing towards higher stream order. All the sub-watersheds in the study area show variation in stream length ratio between streams of different order. Changes of stream length ratio from one order to another order indicating their late youth stage of geomorphic development (Singh and Singh, 1997) Bifurcation Ratio: The bifurcation ratio (Rb) is the ratio of the number of the stream segments of given order Nu to the number of streams in the next higher order (Nu+1) (Table 1). Horton (1945) considered the bifurcation ratio as index of relief and dissertation. Strahler (1957) demonstrated that bifurcation shows a small range of variation for different regions or for different environment except where the powerful geological control dominates. It is observed from the Rb is not same from one order to its next order these irregularities are dependent upon the geological and lithological development of the drainage basin. (Strahler 1964). The lower values of Rb are characteristics of the sub-watersheds which have suffered less structural disturbances (Strahler 1964) and the drainage pattern has not been distorted because of the structural disturbances (Nag 1998). In the present study, the higher values of Rb indicates strong structural control on the drainage pattern, while the lower values indicative of sub-watersheds that are not affect by structural disturbances. The mean bifurcation ratio (Rbm) may be defined as the average of bifurcation ratios of all order (Table 1). In the present case, Rbm varies from.41 to 8.18 and all sub-watersheds fall under normal basin category (Strahler 1957). 764

8 3.1.6 Relief Ratio: Difference in the elevation between the highest point of a basin (on the main divide) and the lowest point on the valley floor is known as the total relief of the river basin. The relief ratio may be defined as the ratio between the total relief of a basin and the longest dimension of the basin parallel to the main drainage line (Schumm, 1956). The possibility of a close correlation between relief ratio and hydrologic characteristics of a basin suggested by scheme who found that sediments loose per unit area is closely correlated with relief ratios.in the study area, the values of relief ratio vary from 1.7 (Tondavadi) to 12.5 (Somanatapura). It is noticed that the high values of Rh indicate steep slope and high relief (25 m), while the lower values may indicate the presence of basement rocks that are exposed in the form of small ridges and mounds with lower degree of slope (GIS 1981). 76 3'45" 76 41'" 76 51'15" Herikatti Thondavadi Horiyala N Begur Hunasinapur Bettadamadaill W S E Hasaguli 11 51'15" Hundipura Madahalli Kabbahalli 11 51'15" Berambadi Panjanahalli Maddur Hongahalli Annur Basavapura Bhimanabidu Hangala Ankahalli Marihosahalli 11 41'" Somanathapura Shettihalla Maguvinahalli Kebeepura 1 Kilometers Chirakanahalli 11 41'" 76 3'45" 76 41'" 76 51'15" Figure 5: Sub-basin of the Watershed 765

9 Table 1: Morphology adopted for drainage morphometric parameters analysis Sl.No Morphometric Parameters Formula Reference 1 Stream order Hierarchial rank Strahler(1964) 2 Stream length (Lu) Length of the stream Horton(1945) Lsm= Lu/Nu Where, Lsm=Mean stream length 3 Mean stram Lu= length (Lsm) Total stream length of order Nu=Total no. of stream segments of order'u' Strahler(1964) RL=Lu/Lu-1 Where, RL=stream length ratio 4 Stream length Lu=The total ratio (RL) stream length of the order'u' Lu-1=The total stream length of its next lower order Horton(1945) Rb=Nu/Nu+1 Where, Rb=Bifurcation ratio 5 Bifurcation Nu=Total no. of stream ratio (Rb) segments of the order'u' Mean Bifurcation ratio (Rbm) Relief ratio (Rh) Drainage density (D) Stream frequency (Fs) Nu+1= Number of segments of the next higher order Rbm=Average of bifurcation ratios of all orders Rh=H/Lb Where, Rh= Relief ratio H=Total relief (Relative relief) of the basin(km) Lb=Basin length D=Lu/A Where, D=Drainage density Lu=Total stream length of all orders A=Area of the basin(km 2 ) Fs=Nu/A Where, Fs= stream frequency Schumn(1956) Strahler(1957) Schumn(1956) Horton(1932) Horton(1932) 766

10 1 11 Form factor (Rf) Circularity ratio (Rc) Nu= Total no. of streams of all orders A= Area of the basin(km 2 ) Rf=A/Lb 2 Where, Rf=Form factor A= Area of the basin(km 2 ) Lb 2 =Square of basin length Rc= 4*Pi*A/P 2 Where, Rc= Circularity ratio Pi='Pi' value i.e., 3.14 A=Area of the basin(km 2 ) Horton(1932) 12 Elongation ratio (Re) P 2 =Square of the perimeter(km) Re=2 (A/Pi) /Lb Where, Re=Elongation ratio A=Area of the basin(km 2 ) Pi='Pi' value i.e., 3.14 Lb= Basin length Miller(1953) Schumn(1956) 3.2 Aerial Aspects Different morphometric parameters like drainage density, texture ratio, stream frequency, form factor, circularity ratio, elongation ratio and length of overland flow have been discussed in detail Drainage Density It is a measure of the length of stream per unit (Hortton,1932) in the watershed.it is significant point in the linear scale of landform elements in stream-eroded topography and does not change regularly with orders within the basin. Langbein (1947) recognized the significance of as factor determining the time of travel by water and he also suggested a drainage density varying between.55 and 2.9sq.km in humid region with an average density of 1.3 sq.km. density factor is related to climate, type of rocks, relief infiltration capacity, vegetation cover, surface roughness has no significance co-relation with drainage density. The amount and type of precipitation can influence directly the quality and character of surface run-off an area with high precipitation as thundershowers loses greater percentage of rainfall absorption capacity of soil, 767

11 which influences the rate of surface run-off affects the drainage texture of an area. The similar condition of lithology and geologic structures semi-arid regions have finer drainage density generally results in the areas of highly resistant or permeable subsoil material, dense vegetation and low relief. High drainage density is the resultant of weak or impermeable sub surface material, sparse vegetation and mountainous relief low drainage density leads to course drainage texture while high drainage density leads to fine drainage texture. The drainage density varies between 1.37 to 4 sq.km indicating low drainage density indicates highly permeable subsoil and dense vegetation cover Form factor The form factor R f points out the shape or outlines form of a drainage basin capable of being understood and affects stream discharge behaviours. the ratio of the basin area to the square of basin length is called the form factor (Horton, 1932). It is dimension less property and is used as a quantitative expression of the shape of basin form. The form factor varies between.3 to Circularity Ratio Basin of the circularity ratio Rc is a shape measured depending on stream flow in the sub basin. (Miller 1953) (Table 1) the circularity ratio is influence by the length and frequency of stream. Geological structures, land use-land cover, climate relief and slopes of the basin. In the present study, the Rc ranges from 4 to.24 high circularity ratio.24 in Panjanahalli subwatershed which indicates that it is more or less circular and are characterized by high to moderate relief and drainage system is structurally controlled. The remaining sub-watershed have less than.24 indicating that they are elongated Elongation Ratio The shape of the any basin is conveyed by an elongation ratio (Re), it is the ratio between the diameter of the circle of the same area as the drainage basin and the maximum Schumm (1956) (Table 1). A circle basin is more efficient in the discharge of run-off than an elongation basin (Singh and Singh 1977). the values of Re generally vary from.6 to 1. over a wide variety of climate and geologic types values close to 1. are typical of regions of very low relief, where as values in the range.6 to.8 are usually associated with high relief and steep ground slope (Strahler 1964). These values can be grouped into 4 categories namely (a) circle (>.9), (b) Oval (.9 to.8), (c) Less elongated (<.7) the elongation ratio of sub-watershed of the study area varies from.21 (Berambadi) to.84 (Panjanahalli). The lowest Re (.21) in the case of Berambadi sub-watershed indicates high relief and steep slope, while very high values in Panjanahalli sub-watershed (.84) with low relief and remaining sub-watershed indicates that plain land with low relief and low slope. 768

12 Sl.No. Table 2: Morphometric analysis of different watersheds of the area Name of the Sub Watersheds Basin in height Total Relief Relief Ratio Ruggedness number Max(Z) Max(z) ( Rr) (Rh) (Rn) 1 HIRIKATI TONDAVADI HORIYALA HUNASANAPURA BEGUR TAGGALURU HASGULI HUNDIPURA MALAVALLI KABBAHALLI BERAMBADI HONGALLI MADDUR BHEMANABEEDU PANJANAHALLI BASAVAPURA ANNUR SOMANATAPURA MOGUVINAHALLI KEBBEPURA SHETTIHALLI ANKALLI MARIHOSAHALLI CHIRAKANAHALLI HONGALA

13 Table 3 (a): Morphometric analysis of different watersheds of the area Stream Order Stream length in km Total Length Sl No Name of the Sub Watersheds N1 N2 N3 N4 L1 L2 L3 L4 Lu 1 Hirikati Tondavadi Horiyala Hunasanapura Begur Taggaluru Hasguli Hundipura Malavalli Kabbahalli Berambadi Hongalli Maddur Bhemanabeedu Panjanahalli Basavapura Annur Somanatapura Moguvinahalli Kebbepura Shettihalli Ankalli Marihosahalli Chirakanahalli Hongala

14 Table 3(b): Morphometric analysis of different watersheds of the area Mean stream length Bifurcation ratio (RB) Mea n RB M Stream Length ratio (RL) Sl No Name of the Sub Watersheds L1/N 1 L2/ N2 L3/ N3 L4/ N4 L2/ L3/ L1 L2 L4/L3 1 Hirikati Tondavadi Horiyala Hunasanapur a 2 5 Begur Taggaluru Hasguli Hundipura Malavalli Kabbahalli Berambadi Hongalli Maddur Bhemanabee du 1 15 Panjanahalli Basavapura N1/ N2 N2/ N3 N3/ N4 L2/ L1 771

15 17 Annur Somanatapur a Moguvinaha lli Kebbepura Shettihalli Ankalli Marihosahall i Chirakanaha lli 25 Hongala Table 3(c): Morphometric analysis of different watersheds of the area Sl.No Name of the Sub Watershed Basin Basin Area in Length Sq.Km (KM) Perimeter (P) in KM Circula rity Ratio (Re) Elongat ion Ratio (Re) Form Drainage Factor Density (Ff) (Dd) Stream Frequency (Fs) Drainage intensity (Di) 1 Hirikati Tondavadi Horiyala Hunasanapura Begur Taggaluru Hasguli Hundipura Malavalli Kabbahalli

16 11 Berambadi Hongalli Maddur Bhemanabeedu Panjanahalli Basavapura Annur Somanatapura Moguvinahalli Kebbepura Shettihalli Ankalli Marihosahalli Chirakanahalli Hongala Conclusion Quantitative analysis of drainage network found that the dendritic to sub dendritic drainage pattern with fourth order streams in all sub watersheds. Stream frequency of all sub-watersheds shows positive correlation with drainage density the variation in values of bifurcation ratio among the sub-watershed is ascribed to the difference in topography and geometric development. The value of drainage density indicating the increase in stream population with respect to increase in drainage density. Drainage density is very coarse to coarse texture. 5. Referernces 1. Agarwal C.S (1998), Study of Drainage pattern through aerial data in Naugarh area of Varanasi District. U.P.J Indian Soc. Remote Sensing 26 (4): AIS and LUS (199), Watershed atlas of India. Department of Agriculture and cooperation. All India Soil and land Use Survey. IARI Campus. New Delhi. 773

17 3. Clarke.J.J.(1966), Morphometry from map, Essays in geomorphology. Elsevier Publishing Company, New York p GSI (1981), Geological and mineralogical map of Karnataka and Goa, Geological Survey of India. 5. Gottschalk L.C (1964), Reservoir Sedimentation in Handbook of Applied Hydrology Ed: VT Cvhow Mc Graw Hill Book Company. New York section Horton RE (1945), Erosional development of streams and their drainage basins, Hydrophysical approach to quantitiative morphology, Geological society of America Bulletin, 56, Langhein WB (1947), Topographic characteristics of drainage basins, U.S Geological Survey, Water-Supply Paper, 986, pp Miller VC (1953), A Quantitative geomorphic study of drainage basin characteristics in the Clinch Mountain area Virginia and Tennessee. Proj NR Tech Rep3, Columbia University. Department of Geology, ONR. New York. 9. Nag SK (1998), Morphometric Analysis Using Remote sensing Techniques in the Chaka sub-basin Purulia District. West Bengal J.Indian Soc Remote sensing 26 (1&2): Nag SK and Chakroborty S (23), Influence of Rock Types and structures in the development of Drainage Network in Hard Rock Area, Journal of Indian Soc Remote sensing 31 (1): NRSA (1995), Integrated Mission for Sustainable Development, Technical Guidelines National Remote sensing Agency, Department of Space Government of India, Hyderabad. 12. Reddy PRR and Rangaswamy CY (1989), Ground water Resources of Pavagada Taluk Tumkur District.Ground water study No 24, Department of Mines and Geology, Government of Karnataka, Bangalore. 13. Singh S and Singh M.C (1997), Morphometric Analysis of Kantar River Basin National Geographica J India 43(1), pp Schumn S A (1956), Evolution of Drainage systems and slopes in Badlands at perth Amboy New Jersey, Geological society of America Bulletin, 67, pp Smith K.G., (195), Standards for grading textures of erosional topography, American Journal of Science, 248, pp

18 16. Srivastava V.K., (1997), Study the Drainage pattern of Jharia Codifield (Burdwan District) as observed on Land-sat TM/IRS LISS II Imagery. Journal of Indian Society of Remote sensing, 23(4), pp Srinivasta V.K., and Mitra D., (1995), Studies on the drainage pattern of Raniganj Conifield (Burdwan District) as observed on Landsat TM/IRS LISS II Imagery, Journal of Indian Society of Remote Sensing, 23(4), PP