Sea Levels Along Visakhapatnam Coast: A Geomorphic Explanation

About 120 km of shoreline in north coastal Andhra Pradesh on either side of Visakhapatnam is rocky with a number of headlands aad bays. Surfaces and caves in rocks along this shoreline were mapped, to explain their relation to sea level stands of Holocene. The physiographic status of surfaces at several locations was worked out in terms of their number and area versus altitude. The seaward margins of hills mapped at many sites along the southern part of the shoreline show a distinct orientation of the outline and dominance of a class of surfaces different from those along the northern stretch. This variability is attributed to the concentration and release of energy of longshore drift and to the variable orientation of the shoreline. Surfaces between elevations of 5 and 1 metre above msl dominate the shoreline. The geomorphic characteristics of these surfaces conform well with those of the storm wave platforms. Sea caves are very few and are associated with either horizontal and/or inclined joints or foliation planes. The 'inactive' cliffs with their toes at about 2 metres above msl along with rocky floors/surfaces with sand cover, point to a sea level stand of 1.00-1.50 metres above the (present) mean low tide level (mltl).