Velocity-Porosity and Velocity-Density Relationship for Shallow Sediments in the Kerala-Konkan Basin of Western Indian Margin

摘要

During the expedition 01 of the National Gas Hydrate Program (NGHP), drilling and coring were carried out at one site in the Kerala-Konkan basin on the west cost of India to validate gas hydrate. Drilling/coring results show a homogenous sequence of oozes and explains that the reflector, which was identified as a bottom-simulating reflector (BSR) on seismic section, is mainly due to changes in formation density because of less clay content in carbonate-rich sediment. Downhole logs collected at this site are of good quality and have been used to establish empirical relationship between the P-wave velocity (V_P), S-wave velocity (V_S), density (ρ) and porosity (φ). The established relations show very good fit with high R~2 value (>0.73), and can be used for further studies in this region. Well known existing empirical formulas between V_P, V_S, ρ and φ deviate significantly from our established relations.