Most scientists agree the asteroid that was most important in the extinction of the dinosaurs hit the Earth at Chicxulub in the Yucatán Peninsula of Mexico. The extinction is in large part linked to the major climatic effects of a huge amount of crustal debris (dust) spewed into the atmosphere at the time of the impact and for years afterwards. Some scientists have suggested another impact off the west coast of India called the Shiva Crater had a role to play. Others also link the extinction to massive volcanic activity in India (Deccan Traps) and its climatic effects.
Answered by: Dr Richard Hebda, curator of Botany and Earth History