Its about landslide hazard zonation of remote areas using RS and GIS techniques. These techniques are accurate and time saving tools.

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2. INTRODUCTION
 Landslide is the movement of earth, mass of rock or debris
along the slope
 Gharwal Himalaya is a part of extra peninsula
 Structural disturbances like folding, faulting, and shearing
are very common in this region
 This area exhibits variety of landslides because of various
natural as well as artificial activities
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3. INTRODUCTION
 Landslides may be ignored if they occur in the area of
no human interest
 But if it occur in areas like roads, agricultural lands,
human inhabited areas then it leads to loss of life and
property
 Minor to major landslides that are very common near
Pipalkoti area on the road of Chamoli to Joshimath
that have increased the maintenance cost of Rishikesh
–Mana Highway
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4. INTRODUCTION
 There is need to study and classify the Himalayan
landslides from road network point of view in
Mountain terrain
 This study is done by available Base maps of area and
their interpolation with RS and GIS to form the
landslide hazard zonation maps of respective study
areas
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5. STUDY AREA
 3 areas have been selected
a ) Gopeshwar city of Chamoli district
b ) Stretch of Chamoli-Joshimath road near
Pipalkoti
c ) Area around Nandprayag
 Area lies in Survey of India toposheet covering
26.18 sq.km, 21 sq.km and 17.63 sq.km respectively
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7. GEOLOGY OF AREA
 There is an intense metamorphosis in area
 Land consist of rocks such as quartzite, gneisses,
marbles and various types of micaceous schist and
slates
 All these rocks have weak cohesion along the plains
 Physiographically the area lies in tectonic , folded and
over thrust mountainous chain.
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8. LANDSLIDE
 Geography and Geology of this area makes it prone to
landslides
 Besides this area comes under zone IV of earthquake
 High flow of rivers and ice melting triggers the action
of landslides
 Besides this road development across slopes and
deforestation adds effect to landslide.
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9. LANDSLIDES
Following types of landslide was observed in study area
1. Slides
2. Falls
3. Flow
4. Topples
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10. ROCKFALL
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11. TOPPLES
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12. SLIDE
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13. FLOW
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14. RS AND GIS TECHNIQUE
 Field survey is most accurate way to study landslides
 But to study large and remote area it is consuming
time and money
 RS and GIS are most effective tools in such condition
to obtain results with good accuracy
 Various satellite images provided by IKONOS, IRS P6,
QUICK BIRD etc can be used as base to study
landslides.
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15. REMOTE SENSING (RS)
 RS data like satellite images and aerial photographs are
used to extract terrain information.
 Satellite data of different years gives information about
changes in geomorphology of area.
 Various factor maps like land use map, drainage map
etc can be prepared from processing of RS data
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16. GEOGRAPHICAL INFORMATION
SYSTEM (GIS)
 GIS has information about different terrain factors in
the form of layers
 With use of GIS software like ILWIS it is possible to
combine the factor map produced by RS with
landslide map.
 This will visualize landslide density in survey area .
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17. ILWIS
 ILWIS (Integrated Land and Water Information
System) is a GIS software developed by ITC,
Netherland.
 It contains both the modules of GIS and image
processing
 It is very fast and accurate tool for processing,
analyzing and representing spatial data.
 It is a useful tool for landslide analysis
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18. Landslide hazard zonation mapping
 There is no basis available to forecast the probability of
landslide occurrence in given time period
 But landslide hazard assessment is possible
 Hazard assessment is the estimation of an area to its
susceptibility to landslide based on few key factors
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19. Landslide hazard zonation mapping
Following data used to measure landslide hazard of an
area:
 Past landslides and their distribution
 Bed rock properties
 Slope of area
 Hydrology of area
 Human factors
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20. Applications of hazard zonation
 It helps to decide land use capability of area
 It shows risk to current land use development
 It shows area vulnerable to landslide
 Based on surveys it helps to predict future landslides
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21. METHODOLOGY
 Remote sensing and GIS are two main methodologies
adopted for landslide hazard zonation
 Remote sensing data used in the form of satellite
imageries
 GIS software is used to interpolate both satellite data
and base maps to form hazard zonation map
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22. RS DATA INTERPRETATION
 Digital data of IKONOS is procured from
www.earth.google.comof all study areas.
 The color composite is prepared in ILWIS in RGB
bands.
 The satellite data is geo-referenced and rectified with
base map of study area.
 Base map is prepared by use of toposheets.
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24. GENERATION OF DIGITAL ELEVATED
MODEL (DEM)
 Base map is imported to ILWIS and converted to
ILWIS data format
 Geo coding and Geo referencing is done to generate a
raster (Images in Geo-Informatics)
 The segment maps are digitized in respective domain
boundaries of area, contours and drainage.
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25. GENERATION OF DIGITAL ELEVATED
MODEL (DEM)
 DEM is prepared after interpolating the contour
segment data
 DEM is analyzed by spatial filtering and slope maps
are derived
 From DEM flow direction and flow accumulation map
is also prepared
 Degree of map was classified as per Young's
Classification
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28. Generation of hazard zonation map
 Satellite data was imported and geo referenced with
base map
 The data is then interpreted by image interpretation
keys and pre occurred landslides and landslide hazard
zones are located
 The slope map layer, flow map layer, drainage layer are
added on RS data to predict the landslide prone zones
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31. Preparing stereo pairs
 From DEM stereo pairs are prepared to view for
various rasters like slope degree map, satellite data etc
 The generated stereo pairs are viewed as ANAGLYPH.
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33. CONCLUSION
 Landslides are Force Majeure.
 When occurred, landslides causes great losses to both
Human and Infrastructure.
 Remote Sensing data has proved to be an effective tool
for landslides study in remote areas like Himalayan
ranges.
 RS and GIS based Hazard Zonation Maps gives
accurate information about the Risk levels in a
particular area.
 GIS techniques found to be very economical for field
study in inaccessible areas.
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