From Earth Magazine:
Sometime between 35 million and 20 million years ago, the Arabian Plate collided with the Eurasian Plate, substantially reshaping Earth’s surface and uplifting the Zagros Mountains in western Iran. The collision may also have played an important role in tectonic and climate changes that occurred about the same time, including global cooling, the opening of the Red Sea and a slowing in the movement of the African Plate. The only problem is that there is little agreement on when the collision actually started. A new modeling approach using rare pieces of ocean crust emplaced on land attempts to narrow that window, researchers reported in Geology.
This story appears in the April issue of Earth Magazine. To request a pdf, please email firstname.lastname@example.org.