Shell concentration stratum of minute viviparid gastropods from Barga Intertrappean Bed, Madhya Pradesh, India - a case study of juvenile mass mortality

摘要

A stratum containing clustered lensoid concentrations of fossil shells of juvenile viviparids is reported from the Cretaceous Barga Deccan Intertrappean Bed of Madhya Pradesh, India. The clustered monospecific viviparid populations of this stratum record their first growth stage. Hence, this is a juvenile mass mortality of viviparids. Deccan eruptive episodes were preceded and accompanied by emanations of huge amount of toxic greenhouse gasses making the environment enormously hot and hypoxic. Thus, eruption-related thermal stress and volcanogenic hypoxicity are probably the main causes for this mass mortality.