Morphological studies of seafloor using multibeam echo sounding data and GIS

Abstract

Two third of the earth surface i.e., 362 million km2 is covered by the ocean. newlineIdentification of prevailing geomorphological processes and the features through newlinemapping of the seafloor provides an important proxy to understand its resource newlinepotentiality, environmental impacts, and the evolution of the surrounding earth crust newlineover time. Post 1980s, improvement of multibeam echo-sounding techniques offered newlinerevolutionary changes in mapping of the seafloor. At present, it is the most efficient tool newlineused for large scale mapping of the seafloor. Combined application of seafloor newlinebathymetry and backscatter strength reveals information related to the sediment types, newlinetectonic features, and small scale geomorphological changes. Besides, single beam newlineecho-sounding data, high resolution seismic reflection data and seafloor sediment newlinesamples are also analyzed and interpreted to validate the primary observations made by newlinemultibeam echo-sounding data. newlineStudy area stretches over 105 km² area and lies at 102 km west off Marmagao newline(offshore Goa) along the central Western Continental Margin of India (WCMI), in water newlinedepths range from 145 m to 330 m. The characteristic of the WCMI, part of which the newlinestudy area belongs, is regulated by episodic changes and dynamics related to its tectonic newlineevolution, eustatic sea level fluctuations, prevailing geology and sedimentation, the newlinepattern of oceanographic circulation and the biological environment. Presence of active newlinebottom currents, parallel to the coast and its seasonal reversal has impacted the fine newlinescale morphological changes of seabed features. Primary objective of undertaking newlinepresent research was to identify the geomorphic features and processes prevailing in the newlineregion by employing multibeam echo-sounding (active SONAR) technique, newlinesophisticated mapping tools and advanced analytical methods (e.g., fractal analysis). newline