In Science this week is news that 80 million years ago sea levels were roughly 560 feet (170 meters) higher than they are today. Science have news report on the story (which will link to the paper if you are on a campus computer or using the library proxy).
In the age of the dinosaurs, great inland seas kept the climate balmy and redirected the course of evolution by opening huge new niches. But these seas weren't constant, and scientists have long debated how high they rose and why. A new study finds that global sea level was 170 meters higher than today and chalks the dynamism up to an ever-changing sea floor.