Lack of success in Kerala-Konkan basin in the southern part of western continental margin of India is attributed mainly to not sufficient quantity of source rocks at depth suitable for generation of hydrocarbons. Hence, identifying areas with thick pile of sediment is one of the important exploration objectives in the basin. We have used gravity and magnetic data for estimation of sedimentary thickness over Aleppy platform and the area to the north of it in the southern part of Kerala basin. Integrated interpretation and modeling of gravity and magnetic data has given a good estimate of sedimentary thickness in the area, which was not possible with seismic data because of its poor quality. Features on gravity anomaly map over Aleppy platform in the southern part of the area are mainly controlled by basement. Absence of crustal thinning, deep Moho (unto 35 km) and its gentle slope indicate that Aleppy platform is a continental block and is a remnant from the break up of India from Madagascar and Seychelles. This is further supported by the absence of Miocene shelf break in seismic data over Aleppy platform signifying either rifting was not complete or did not take place in this part.