11. The space left behind by departing lithosphere is filled by upwelling asthenosphere. 12. This slow anomaly is considered to be a plume upwelling . 13. Large-scale upwelling is found in the Southern Ocean. 14. By alongshore winds, upwelling current flows to the coast. 15. The coastal upwelling in the south-eastern Arabian Sea occurs seasonally. 16. When El Nino starts, the upwelling diminishes and the surface waters warm. 17. Coastal zones provide nitrogen from runoff and upwelling occurs readily along the coast. 18. Natural causes include coastal upwelling and changes in wind and water circulation patterns. 19. The intrusions were formed when upwelling asthenosphere partially melted thick overlying oceanic crust. 20. It was suggested that the cause was mantle upwelling .
