J. P. Sep Nlomngan, S. P. Mbola Ndzana, P. Nguet Pountougnigni, S. Nguemhe Fils and J. Penaye

The convergence of forms and orientations between hydrographic networks, landscape and geological structures (faults, tectonic lineaments, breakthroughs) increased in mountain chains and especially in the humid tropical domain (The World Atlas) where precipitations are quite important, raises the issue of the relation and/or the influence of geological structures on nature and on hydrographical network structures. Many fieldworks on computer modelling carried out in great mountain chains (Andes Mountains) show that interactions between topographic construction, deformation, climate and erosion process can shape the structural evolution of orogens. Ganwa’s works (2007) realised in the southern part of our study area show that there is a close relation between tectonic lineaments, topography and hydrography. The aim of this work is to show the influence of breaking tectonics on the guidance of stream flows. To achieve this, we will base ourselves on a comparative study of hydrography, structural analysis and landscape morphology.

Ground penetrating radar a tool to map the seismicallyinduced fault and fracture in the coastal cliff of east coast of port blair, Andaman

P. Prasad, N. Ramanujam, A. Vignesh, S.H.K. Murti, Qazi Akhter Rasool, S.K. Biswas, Chandrakant Ojha and A. J. Boopalan

Frequency of Earthquake-induced landslides or “seismic landslides”, are increasing in recent years throughout the world and mounting grim situations due to the heavy damages caused. Seismic shaking produced additional inertial loading on normal stable slopes and triggered landslides and also reactivating dormant landslides. The 26 December 2004 Sumatra-Andaman earthquake with magnitude Mw 9.3 caused uplift in western and submergence in eastern part of entire island system of Andaman and Nicobar and also instigated subsidence, ground deformations and landslides, in the interior part of the islands and also along the coastal regions of Andaman Islands. Coastal landslides or water front landslides occurred in many parts of Islands. An attempt is made to bring out the triggering instant of earthquake-induced coastal landslides along the coastal cliff section in the Eastern part of Port Blair to a distance of three km. through the geophysical technique Ground Penetrating Radar. The coastal landslides cropped up in the wave front exhibit vertical or near-vertical rock faces to heights of up to 15-20 m from mean sea level in the coastal. Those Coastal landscapes typically consist of an alternate layers of clay, silt and sandstone formations of Andaman flysch deposits. The seismic shaking has initiated widespread ground fractures and cracks it dissipates seismic energy due to acceleration of cliff section. Mapping of the lateral and depth wise extension of the internal failure structures in vertical and horizontal discontinuities in the subsurface in the promontory of sea cliff were mapped through Ground Penetrating Radar (GPR) to identify the intersection of discontinuities oriented in N-S and E-W and demarcated as risk zone.

Land cover is the assemblage of biotic and abiotic components on the earth’s surface and has direct concern with ecology. The sensitivity of the earth’s climate as well as ecological system depends on land cover changes. This gives immense importance to study the land cover changes especially when satellite data provides timely and efficient information about large land area. In the present paper, the study was carried out by using NASA’s hyperspectral EO-1 Hyperion sensor for middle and upper zone of Himalaya. The analysis procedure consists of Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) atmospheric correction code derives its physics-based algorithm from the Moderate Resolution Transmittance (MODTRAN4) radiative transfer code as well as radiometric (atmospheric + topographic) correction to retrieve surface reflectance. Various statistical models for supervised classification such as spectral angle mapper (SAM), support vector machine (SVM), and maximum likelihood (MLH) has been examined and validated with existed Normalized Difference; Vegetation Index (NDVI), Snow Index (NDSI) and Glacier Index (NDGI) models. The spectral reflectance of different surface parameters has been collected in field, using spectro-radiometer and compared with satellite derived spectra. Presently land cover classification accuracy assessments are based on error matrix, which is a simple cross-tabulation of the mapped class against that observed in the reference data at a set of validation. Study distills these statistical approaches into a unique set of hierarchical taxonomy that reveals the similarities and differences between algorithms.

Resistivity steps as a precursor and impending earthquakes of aftershocks of great earthquake of 26th December 2004 recorded at idukki observatary, Kerala, India

Antony Ravindran A. and Ramanujam. N

The study of resistivity relaxation before the impending earthquake events occurred during January-February 2005 in the Andaman-Sumatra subduction zone have proven the existence of the long range effects of strain related precursors, fortuitously recorded by the Variometer designed to reflect the premonitory rupture in Kottayam, Kerala, India at epicentral distances greater than 2000 km. The swarms of the aftershock of Great earthquake of 2004 supplied sources of seismic waves that have been subsequently scattered, polarized and lead to the process of birefringence through the anisotropic rocks. The average values of earthquake magnitudes (M5.3), epicentral distances (1941 km), radius of preparation zones (281 km) and focal depths (23 km) are calculated from the regression equations evolved from the bivariate plots. The abnormal increase of crustal strain even for a lower earthquake of M5.3 which has definitive radius of the preparation zone of 240 km to an ultimate radius of more than 5400km from epicenters to observatory is discussed.

The stability analysis of internal overburden dump reinforced with geosynthetic in open pit mine “Kosovo”

Sabit Klinaku, Sefedin Kastrati, Beqir Mehmeti and Gazmend Gashi

This paper discusses the slope stability analysis of internal overburden dump called “East Dump” in open pit coal mine “Kosova”. In this dump continually occurrence slide of the materials that have been dumped (yellow and grey clay). For solution of the dump stability problem, firstly is analyzed current situation of the dump, then dump design and in the end dump design - slope reinforced with geosynthetic/geogrid. The primary aim of design of internal overburden dump is to provide effective stable working conditions for tow stackers. The slope stability and factory of safety was analyzed in selected location along the slope by using limit equilibrium method, such is Bishop’s method. The analysis has been done using Mohr-Coulomb model by using GGU-STABILITY software. Finally, a economical, sustainable and stable dump angle and height was analyzed for a safe dumping.