The British Isles are away from the plate edges where most disruptive geologic activity occurs (earthquakes, volcanoes, subduction, etc). The rest of Europe is along the edges of the plate and was geologically active. If you look at North West Brazil you can see very little happens for over 240 million years (away from plate edge) while Oceania has been very active for the last 100+ million years (and is still very active).

If you look at the ocean while you go back in time you can see large swaths that have very little detail. This is because that rock has been geologically recycled and is no longer part of the geologic record.