Earth's Lower Mantle (image) Science China Press Share Print E-Mail Caption The schematic artwork shows a boundary within the lower mantle at the depth of 1900 km. Below 1900 km, the interaction between water and mantle is triggered. Credit ©Science China Press Usage Restrictions Use with credit. Share Print E-Mail 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.