Upwelling regime in the Carpathian Tethys: a Jurassic-Cretaceous palaeogeographic and paleoclimatic perspective

Abstract

Jurassic and Cretaceous global palaeogeographic reconstructions show a changing configuration of mountains, land, shallow seas and deep ocean basins, and these are used as input for paleoclimatic modelling. We have generated Oxfordian-Kimmeridgian, Tithonian-Berriasian and Barremian-Hauterivian paleoclimatic maps, showing air pressure, wind directions, humidity zones and areas favourable to upwelling conditions, modelled by the PALEOCLIMATE program and plotted on the palaeogeographic background. Paleoclimate modelling suggests that prevailing Jurassic-Cretaceous winds in the northern Tethys area came from south-south-west, and may have been parallel to the Czorsztyn Ridge, uplifted as a result of extension during the Jurassic supercontinental breakup. Upwelling may have been induced at the southeastern margin of the ridge. The model is consistent with the rock records within the earliest Cretaceous deposits. The presence of phosphates and a palaeoenvironmental analysis of benthic fauna support the upwelling model.