You see an increase in volcanism into the Tertiary and you see several orogenic episodes starting in the Jurassic.
So, to be clear, is all such dating to time periods done by radiometric methods? When it is said that mountains formed in such a such a time period, that's due to radiometric measurement? Of what, exactly? Is that how the Cratonic transgressions are dated? (And is anyone paying attention to all this in relation to the movement of the Supercontinents and the breakup of Pangaea and all that? Because the seafloor would not have spread as far in the Cretaceous as today for instance. Is all that being taken into account?
ABE: So for instance if Pangaea broke up in the Jurassic there was really not a lot of seafloor formed by the Cretaceous? )