Overview | Earthquake | Drought | Fire | Flood & Cyclones | Landslide & Soil Erosion | Volcano
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Previous Disaster Assessment Of Earthquake Using GIS and Remote SensingSatellite Images Landsat ETM plus Image, Aster Ortho Images Satellite images has been acquired for visual interpretation.  Data preparation has been completed through Scanning, Georeferencing, Sub setting, Digitizing and Attribute entry. Maps and Satellite images has been Georefrenced for identification of different locations and analysis purposes. Digitization and Attribute entry DEM AND ASTER ORTHO images of Area of interest have been clipped through sub setting. Seismic Maps of Balakot and Muzaffarabad Seismic Maps of Balakot and Muzaffarabad have been digitized for classification and its attributes are entered in the table by NESPAK and its attributes have been entered in the table. Landslides have been digitized from ASTER_ORTHO images. Soil Survey of Pakistan has digitized soil Maps for classification according to the soil type. Fault lines from Fault line maps have been digitized. Attributes of soil types, characteristics etc have been entered in Soil and Seismic Maps. Processing These are the data processing steps.
Soil maps have been classified according to the soil types. Soil is classified into Rockland, Maria, Batgran shohal , Khurita, Mani, Nara , Shaldar, Ban, Paras, Kurnol, Chhapri, Baragali, Didal and Kaghan. Classification of Seismic Map NESPAK has classified Seismic maps of Muzaffarabad and Balakot according to its hazardous zones. Fill sinks Fill sink operation has been used to removed the local depressions (sinks) of DEM . Slope Map Slope maps of Dem of 2000 and 2005 has been clipped through applying spatial query in ILWIS and categorized into four classes Low, moderate, steep, steepest, where the slope angle is equal to and greater than 45° is considered as Steep slope. By Omer Ayden in International Conference on 8th October 2005 Earthquake in Pakistan “A Geodetic Evaluation of failures of Natural and cut slopes caused by Kashmir Earthquake of October 8, 2005 and their implications on civil infrastructures and site selection”. Aspect Map Aster_DEM_2000 and Aster_DEM_2005 are the aspect maps. These are used to show slop directions.  Fig-11: Aspect Map of Muzaffarabad Balakot. Sub setting Slope map has been clipped according to soil by applying the query in ILWIS. Methodology To know the influence of physical parameters of landslides, we have to know the correlation between the occurrence of landslide and parameters such as soil type, slope, land use, elevation data, moisture content geology and seismic intensity can be analyzed. Through querying and overlay analysis the resultant maps we may conclude our results according to our research questions.  Analysis To know the influence of physical parameters to landslides the correlation between the occurrence of landslides and parameters can be analyzed. As land use, moisture content is not available so we may be able to analyze the influence of landslides by using the slope, soil type, seismic intensity and elevation data through overlay and querying these maps. 1- Landslide and Soil Map Analysis The resultant map of Landslide and Soil Map after applying the spatial query in ILWIS, it show the soil type where landslides exist. These are Batgran Shohal, Ban cultivated, Ban rockland, Baragali, Kurnol, Nara, Mani, Maira, Rockland, Paras cultivated soil types. Through visual interpretation and spatial query analysis it is concluded that maximum of the landslides are present where Rockland, mani and Kurnol soil types are found.  Fig-13: Soil Map of Balakot Muzaffarabad  Fig-12: Slope Map of Balakot and Muzaffarabad.   Fig-13: Soil Map of Balakot Muzaffarabad 2- Seismic and Landslide Map Analysis The seismic hazard microzonation maps of Balakot and Muzaffarabad have been categorized into four classes according to its hazardous conditions. These are Highly hazardous, High hazardous, Medium hazardous and Low hazardous. Through overlay analysis between Seismic and Landslide maps it is concluded that the most of the landslides have been found in highly hazardous areas and the residual landslides are in high hazardous areas.  Fig-14: Seismic Hzardzonation Mapof Muzasffarabad, 2005.  Fig-15: Seismic Hzardzonation Mapof Balakot, 2005. 3- Slope, Aspect and landslide Map Analysis After overlay and querying analysis of slope map and landslide map it is concluded that 80 to 85 percent landslides have been occurred at slopes greater than 45 degree. According to the research slope has been divided into four classes low, moderate, steep and steepest   Fig-16: Soil Type in Hazardeous area of Balakot Muzaffarabad, 2005. .After overlay and querying analysis of Aspect map and landslides it has been concluded that the 80 to 85 of the landslides occur at west, southwest and northwest directions. The Aspect map has been acquired according to landslide map by applying the query in ILWIS.   Fig-17: Landslides in Balakot and Muzaffarabad according to Aspect Map, 2005. Elevation Model Analysis For the study of elevation changes between DEM 2000 and DEM 2005. The Elevation values of Digital Elevation Model of year 2005 have been subtracted from elevation values of Digital Elevation Model of year 2000. By overlaying the fault line map on this map we can view easily that the changes are lie along the fault lines especially in Northeast area, which is closer to the Epicenter. But there are no definite results about this analysis.  Fig-18: Changes shown along Fault lines. Conclusion The disaster assessment is an evaluation of a natural occurrence. It should be accomplished through the field survey of the affected areas within the limited resources. There is a need for information about the extent and the concentration of damaged area in critical hours. The information should be accurate, reliable and provided in a timely and appropriate manner. Remotely sensed data make us able to depict disturbed vegetation, denuded hill slopes, and shallow landslides etc in the natural terrain. The identification of risk areas, rate of destructions/causalities and understanding of post and pre disaster scenario becomes easy to understand by using GIS and remote sensing derivation of hazard zonation maps. According to the slope map and landslides analysis it is estimated that Maximum of the landslides occurred where slope angle is greater than 45 degree. Through analyzing Aspect map and landslides it is concluded that the 80 to 85 percent andslides occur at west, southwest and northwest directions. Overlay analysis of seismic map digitized landslide map shows that most of the landslides exist at highly hazardous areas and residual landslides exist in high hazardous areas. It also shows the probability of occurrence of landslides at high hazardous regions and most of the landslides occur at the soil types of Mani, Rockland, Maira, Ban Rockland, Kurnol, Nara and Baragali. Since the soil type of high hazardous areas and highly hazardous areas are same so there is also a probability of possibly occurrences of landslides. It has also seen that after earthquake the area of landslides increases from 2.669 square Kilometers to 5.314square Kilometers. Recommendation The study has shown the dangerous areas regarding earthquake. GIS based research has also provided maps, which are helpful in planning and development. These are also useful in early warnings so we may save from further loss. Landslides have also identified in affected area within short time with the help of GIS tools but it is not the end of research. The further study can be procceed by using more topographic information or high-resolution spatial data. 1- By adding the more information like geomorphologic, Geologic, land use etc the Hazard map would be formed. 2- Further research can be made on the Elevation change. References:
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