Earth's surface periodically moves up and down

18 May 2016

This is a hot potato in some ways as it has been found the Earth's mantle flows and causes the crust to periodically move up and down. This observation was fine and dandy in a uniformitarian or gradualist timescale but it seems it may occur much more often than previously allowed - and the big question is how often that might be. See http://archaeologynewsnetwork.blogspot.co.uk/2016/05/first-global-map-of...

Steve Mitchell has postulated in the pages of SIS that the land can rise or sink in relation to the sea level. In other words the amount of water that is the oceans remains the same but it is the land that may rise or fall and affect our concept of sea level change, pointing a finger at early Christian churches in Scotland stranded a long way back from modern sea shores but once located much closer. Inland lochs in Scotland also appear to have been muchbigger affairs in the not too distant past. This is usually attributed to isostatic and eustatic processes going back to the removal of weight from northern Britain, the ice caps that once covered it, resulting in a process of bounce, the land still reacting by going up (but interrupted by episodes of going down again). Well, is that well embedded theory the full story. Could mantle flow also play a role?

Geologists are also interested in whether or not mantle flow might affect mountain building episodes, the eruption of volcanoes and other seismic activity, and so on. The article is in May's issue of Nature Geoscience and considers how it might affect the sea floor, ocean currents and circulation patterns (and therefore climate change). The research was done by Cambridge University.

See also http://phys.org/print382011923.html ... earth's surface moves up and down like a yo-yo. See also DOI:10.1038/ngeo2709