Archaean Plate Tectonics (IMAGE) University of the Witwatersrand Caption A diagrammatic representation of the Earth in the Archaean showing subducted ocean floor carrying its chemical signature into the deep mantle. The signature which includes water and chlorine is preserved in melt inclusions contained within olivine and carried back up to surface within komatiite lava flows. Credit Figure created by research team for news release. Wits University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.