International Journal of Scientific Engineering and Research (IJSER) www.ijser.in ISSN (Online): 2347-3878 Volume 3 Issue 3, March 2015 Licensed Under Creative Commons Attribution CC BY Landslide Hazard Investigation in Papua New Guinea-A Remote Sensing & GIS Approach Sujoy Kumar Jana 1 , Tingneyuc Sekac 2 , Dilip Kumar Pal 3 Abstract: Tribal communities living in the mountainous regions of Papua New Guinea (PNG), often experience frequent landslides during the rainy season. The Eastern Highlands Province (EHP) is one such landslide prone province located in the mountain regions of PNG. Landslide is classified as a natural hazard that has a critical geological process to inflict an enormous damage to civil engineering structures including other valuable assets. The research study was aimed to monitor and assess landslide hazards by remote sensing data processing and GIS spatial analysis. The occurrence of landslide is controlled by a number of morphological, geological and human factors. However, according to the availability of data, only certain principal factors are considered in the present study. The analysis focuses certain landslide contributing factors in generating landslide hazard map of the area. For this study, ranking, classification and weighted overlay analysis techniques were commonly used to generate landslide hazard map. Keywords: GIS, Hazard Map, Landslide, Potential Index, Remote Sensing 1. Introduction Landslides in mountainous terrain often occur during or after heavy rainfall, human activity like indiscriminate felling of forests on steep slopes and / or natural tectonic processes inducing earthquakes result in the loss of life and damage to the natural and /or built environment [3]. When these activi- ties happen and shear stress exceeds the shear strength of the material, then the landslide occurs. The downward move- ment of surface material takes place under the influence of gravity, and the mobility of such movement is enhanced by water content in the sediment [3]. Since the early 1970s, many scientists have attempted to assess landslide hazards and produced susceptibility maps portraying their spatial distribution by applying many different GIS based methods. The results of published papers show that landslide suscepti- bility and hazard maps have become very effective tools for planners and decision makers [5]. It is understood now that in order to delineate or generate the landslide hazard maps, in addition to tectonic instability of the terrain certain geo-morphological and geological factors like lithology, slope, rainfall, land use land cover, soil type etc. are to be considered. Thus these factors are the contri- buting factors to occurrence of landslide. All the factors are processed in the GIS environment to come up with landslide hazard map. Landslide hazard (LH) defines the physical attributes of a potentially damaging landslide in terms of mechanism, volume and frequency and therefore landslide hazard assessment (LHA) estimates the probability of a landslide occurrence within a certain period of time in a giv- en area [5]. 2. Study Area The area selected for the research study for landslide hazard zonation is in the Eastern highlands province, located around Latitude 60 30’ S and Longitude 1450 30’ E. It is in the mountainous region of PNG. Whole part of the province is assessed for landslide hazard. The total study area is approx- imately 11,200 sq kilometres. Figure 1: location map of the study area 3. Data Used and Methodology Table 1: Different data layers/maps Data Layer Source Soil data/map for EHP PNGRIS metadata Landsat8 Satellite data(28.5 spatial resolution) captured 2008 for whole PNG Surveying and lands de- partment-PNG Unitech Landform and Lithology data/map for EHP PNGRIS metadata Rainfall data for EHP PNGRIS metadata DEM data(SRTM) for PNG(90m spatial resolution) Surveying and lands de- partment-PNG Unitech Vegetation type PNGRIS metadata Terrain data (slope and Height) Surveying and lands de- partment-PNG Unitech Soil, rainfall, landform, vegetation type and lithology data for Eastern highlands province was collected from surveying and lands department at The PNG University of Technology. The data was again in the GIS environment was updated using the satellite images and according to PNGRIS data, it was again reclassified and was assigned a specific value. The metadata was rectified to WGS 1984 UTM zone 55. Land use and land cover type for the EHP were prepared from Paper ID: IJSER1539 79 of 83