Deep degassing as a reason for abnormally high bioproductivity of paleobasins and mass destruction of hydrobionts

Abstract

An abnormally high bioproductivity of modern water basins arises as two factors are combined, i.e., cold surface waters rich in oxygen and moderate gas flows ascending from the fault zones at the sea bottom. Gas bubbles bring nutrients of endogenous nature to the surface; these are nitrogen, phosphorus, and microelements, which provide rapid development of phytoplankton, the basis of food chains. Quasiperiodic intensification of deep degassing results in reducing gases blowing through the surface water layer and rapid mass destruction of the aerobic biota and intense development of anaerobic organisms (red tide). This scenario also occurred in the past geologic epochs.