GEOMORPHOLOGICAL ANALYSIS USING REMOTE SENSING AND GEOGRAPHICAL INFORMATION SYSTEM

TECHNOLOGIES IN BARTIN (NW TURKEY) AND ITS VICINITY.

Dr. Hüseyin TUROĞLU and Hasan ÖZDEMIR Istanbul University, Faculty of Letters, Department of Geography, Laleli, Istanbul, Turkey

ABSTRACT Remote Sensing (RS) and Geographical Information System (GIS) Technologies used in geomorphological investigations give incredable advantages. One of the geomorphological studies is designing and analysis of geomorphological units. The aim of this study is to analyse geomorphological units of Bartın territory (NW Turkey) by using Remote Sensing and Geographical Information System Technologies. For this purpose, LANDSAT 5 Thematic Mapper (TM) scenes of the study area used to data collect based on spectral reflectance properties of land , 1/25000 scale topographic maps digitalized to consist of Geographical Information Systems database for morphometric analysis and also ERDAS 8.5, ARCVIEW 8x softwares were used. The basic geomorphological units such as mountainous areas, plateau, lowlands and metric properties of these units, etc. was not only dissected but also calculated and maped in RS and GIS Technologies. The results of applying RS and GIS for Bartın was tested in field season. For instance, geomorphological data produced with unsupervise classificatons based on spectral reflectance features and signatures checked and clearly named and collected new spatial data by using Global Positioning System (GPS) on field. Finally, Geomorphological features of Bartın and its territory explained as units and types, quantitative results and digital mapping Keywords: Geomorphological analysis, RS, GIS, Bartın (NW Turkey). INTRODUCTION Although Bartın (NW Turkey) and its vicinity has been decleared as study area, Bartın River basin was considered as study area on account of showing a wholeness of it. Bartın River basin is an area attracting attention with geomorphological diversity, rough morphology, river system. These features of basin can easly notice ıf anybody looks through at the Digital Elevation Model (DEM) of Bartın River basin (Figure 1). Because of having physical environment properties, some natural disasters such as sheetflood, flashflood and flood, mass movement, erosion, etc. causing important economic loss for Bartın city and Turkey, occur in Bartın River basin. As we have thought of contributing to activities of precaution and mitigation, we targed to geomorphological analysis of Bartın River basin using Remote Sensing and Geographical Information System Technologies. Otherwise, result of this study not only can use natural disaster purpose but also applicable different aims with great advantages in management of environmental investigates, natural resources, planning, etc. Its important feature that R.S. and G.I.S. technologies have been used during all stages of study. The application of R.S. and G.I.S. technologies provides advantages such as data collection, morphological analysis, designing of geomorphologic units and result of presentation.

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Figure 1: Digital Elevation Model (DEM) of study area and its location. PROCESS Realization of morphological analysis of Bartın River basin have been used to R.S. and G.I.S. technologies. Components of analysis concept have been classified into two groups. Data and material is the first component of this study. Other component of investigation is method and extend of elements. Raw data and materials Landsat 5 TM (1987) satellite images have been used as data resources for geomorphological characteristcs of study area. Ground resolutions of used satellite images have 30 m (band number 1, 3, 5, 7). Other data resources of investigate have been 1/25 000 scale topographic maps used to create data base for Digital Elevation Model (DEM) and another analysis. Method Even though there are a lot of data resources for geomorphic diagnosis It is clear that morphometric and river system informations of Bartın River basin contribute to basically both interpretation and designation on geomorphological units within basin (Knigton, 1996, Turoglu, 1997, Luan – OANH, 2002, Sarapirome, and etc., 2002 (Figure 2).

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• Topographic maps have been converted from anolog environment to digital environment. • Using control points, digital maps have been rectified with between 0,5-1.0 RMS in

UTM Projection (36 N). • Creating database which are consisting of graphic and attribute data have been depend

on rectified digital maps. • Triangulated Irregular Network (TIN) of basin has been created by means of 3D Analyst

extention of ArcView 8x.

Application of RS and GIS Technologies

Morphological Analysis Drainage System of Bartın River

Spectral Reflection Bifurcation Rate Hillshade Stream Length Slope and Aspect Stream long profiles Topographic profiles Hypsometrik Curve Lineaments

Classify of geomorphological unites of study area Figure 2: Components of framework of study to designation of geomorphological units.

• Slope and aspect maps have been constituted with opportunity of “Surface Analysis” in same extention as 10*10 m cell size (Figure 3- 4).

• Because of the fact that it refer to the best interpretation in spectral bands, Band number 5:3:1 and 7:3:1 of Landsat 5 TM (1987) satellite images have been composed to geomorphological interpretation (Figure 5 - 6).

• Shaded relief images has been created from multiple raster data using 450 of sun angles and 3150 for sun azimuth (Figure 7).

• Topographic profiles which are directions as NE-SW and NW-SE of study area have been prepared (Figure 8).

• Bifurcation rate (Figure 9-Table 1), Hypsometric curve (Figure 10), Stream length, Stream long profiles (Figure 11) was calculated and designed due to using for geomorphological interpretation in GIS environment.

• Finally, geomorphological analysis of Bartın River basin has been finished by means of consideration in using all data collecting RS and GIS technologies (Figure 12)

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Figure 3: Slope map of Bartın River basin.

Figure 4: Aspect map of Bartın River basin.

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Figure 5:, Landsat TM (1987) Composed image, band number 5:3:1.

Figure 6: Landsat TM (1987) Composed image, band number 7:3:1.

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Figure 7: Shaded relief images created from multiple raster data using 450 of sun angels and

3150 for sun azimuth of study area.

Figure 8: Topographic profiles which are directions as NW-SE and NE-SW (Figure 1) .

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Figure 9: Subbasin and bifurcation rate of Bartın River basin.

Table 1: Stream Order and Bifurcation Rate analyses of Bartın River. Subbasin 1.Order 2.Order 3.Order 4.Order 5.Order 6.Order Total

Karaçay 31 8 2 1 - - 42

Arıt 83 19 5 1 - - 108

Geçen 47 13 2 1 - - 63

Ulus 79 18 4 1 - - 102

Close basin 15 4 1 - - - 20

Gökırmak 135 40 7 2 - - 184

Kocanaz 426 109 17 4 1 - 557

Bartın 95 24 5 - 2 1 127

TOTAL 911 235 43 10 3 1 1203

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Figure 10: Hypsometric curve of stuy area prepared according to data of elevation and area.

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Figure 11: Stream long profiles of Bartın River tributaries.

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RESULTS OF ANALYSIS The fact that composed satellite images as analysed in GIS, shaded relief images, slope and aspect analyses, Analyses of Bartın river system have been commented on geomorphological determination purpose, It has been described to landforms as lineaments, extent, size shape and height of morphologic units, and also drainage pattern, dispersal and displacements of riverbeds into basin. According to result of analysis, four basic geomorphic units was classified in study area (Table 2). Spectral reflections, hillshades, slope, aspect images infere both visual and numerical interpretation for basin. Some quantative informations such as elevation of long profiles, numerical value of flats taking place different elevations, bifurcation rate, stream orders and frequency of Bartın River and its tributary (Table 1), stream length, areas having different slope degree have contributed to make definite of visual interpretation (Figure 12). According to result of analysis, some lineaments which are used as lineament escarpments without infere to fault, structural line or articulation line have been drawn on geomorphological map. Table 2: Area and proportional dispersion of geomorphological units within Bartın River Basin (Figure 12).

Geomorphological Units Area ( km2)

Percentage in basin ( % )

Mountain Environment 236,9500 11,51 Highest Plateaus 271,1750 13,17 High Plateaus 433,7325 21,06

Plateaus

Low Plateaus 676,4850 32,85 Valley Slope and Hills 193,7450 9,41 Transitional areas Valley floor and Low Ridges 189,1800 9,19 Fluvial terraces (T1) 10,7575 0,52 Lowlands Fluvial Terraces (T2) 47,2025 2,29

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Figure 12: Geomorphological analysis realized by using all data collecting RS and GIS

technologies of Bartın River basin. Mountain Environment This geomorphological unit generally represented with over 1000 m elevation in study area. Mountain environment classified by using satellite images in RS and analysis in GIS attract attention with rough surfaces, steep slopes, probable steep fault scarps. Plateaus Three plateaus surface named as Highest Plateaus (250-450 m), High Plateaus (550-700 m), Low Plateaus (850-1000 m) have been classified to use slope breaks calculated topographic profiles, hypsometric curve, stream long profiles within study area (Table 2). Plateaus are total 1381,4925 km2 that represent 67,08 percentage of whole basin. Low plateau surface is largest in area with 32,85 % (676,4850 km2) in basin. Highest Plateau surface is smaller then other two plateau surfaces. Plateau surfaces is usually formed by lineaments which are probable fault traces in study area. LOWLANDS Lowlands where fluvial deposit areas easily noticeable with light color on satellite images and able to mark boundary of these lands. Satellite images have been classified as unsupervise classify on RS, then tested all type of fluvial deposits within field. Other information about making a decision for lowland forms has been used as GIS analysis methods. Especially, river system features such as meandering drainage directly refer to lowland in Bartın River basin.

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Alluvial terraces DEM data, spectral reflection features of satellite images, topographic profiles have shown that two alluvial terraces calling as T1 (about 20-25 m) and T2 (about 13-17 m) take place within lowland of Bartın River basin. Floodplain Bartın River foodplain have the relatively broad and smooth valley floors constructed by Bartın River and periodically covered with floodwater during periods of overbank flow becoming frequent year by year. The fluvial activities of Bartın River are both active horizontal erosional and depositional activity in floodplain which consist of a great variety of depositional materials, including colluvium (debris from valley sides), channel deposits (sand and gravel), and vertical accretion deposits (clay and silt deposited by overbank flows). Spectral reflection features of lowlands have helped to understand of landforms. Ground features such as moisture, texture, pattern, size are importand basic elements for interpretation of satellite images. In classification of floodplain of study area has been benefited from these information. CONCLUSION In this study, geomorphological analysis had been aimed using Remote Sensing and Geographical Information System Technologies. DEM, slope map, aspect map, shaded relief, topographic profiles, subbasin and bufircation rate, hypsometrik curve, geomorphological map of Bartın River basin was created by means of these methodologies. These maps were prepared not only according to result of analysis in office but also testing and surveying in field. Using of these technologies show that obtained data and created images are able to share with all scientific branchs and different purposes. In addition, obtained data and created images which are numerical, reliable for truthful of its and able to convert to different using demonstrated that RS and GIS Technologies have been making sure integrate with all scientific branchs of geography science and geographical data. References Knigton, D., 1996. Fluvial Forms and Processes, Arnold, a Member of the Hodder Headline Group, 338 Euston Road, London NW1 3BH, UK. Luan, T.X. – OANH, T.T., 2002. Applying Remote Sensing and GIS to Research Modern Geologicaal Environment at the Bach Dang River Mounth Area, Part II Remout Sensing and Geographic Information Systems (GIS) Applications for Sustainable Development, pages:74-78. Sarapirome, S.-Surinkum, A.-Saksutthipong, P., 2002. Application of DEM Data to Geological Interpretation: Thong Pha Phum Area, Thailand, http://www.gisdevelopment.net/oars/acrs/2002/geo/029.pdf Turoğlu, H., 1997. Quantitative Approach to Hydrographic Features of Iyidere River, Turkish Geographical Review, volume 32 p:355-364, Istanbul.