Which was not included in the support for Harry Hesss hypothesis of sea-floor spreading?
One key piece of evidence not included in support of Harry Hess's hypothesis of sea-floor spreading was the discovery of paleomagnetic data. While Hess's theory focused on the creation of new oceanic crust at mid-ocean ridges and the recycling of crust at subduction zones, the paleomagnetic records provided insights into the historical movement of continents and the magnetic orientation of rocks, which later supported the theory of plate tectonics. Other evidence, such as the age of oceanic crust and the distribution of fossils, played a more direct role in supporting his hypothesis.