查看文章

THE collision of India with Asia¹ had a profound influence on late Cretaceous and Cenozoic oceanography², climate³, fauna! extinctions⁴ and the motion of at least some of the Earth's litho-spheric plates⁵. As the collision ended a period of rapid Indo-Asian convergence⁶, a precise knowledge of its timing (when the crust of the neo-Tethys ocean was completely subducted⁷, at some point along the plate boundary) is important for understanding its wider consequences. But current estimates of the collision age range from 65 to 38 Myr before present^{6, 8–11}. Here we report the results of extensive biostratigraphic analyses from Waziristan and Kurram in northwest Pakistan, which show that accretionary-prism and trench strata were first thrust onto the northwest Indian passive margin after 66 Myr but before 55.5 Myr. After this time, volcanic-arc fragments, the accretionary prism, trench material and imbricates of the …