I learned a new word in Science this week: Speleology: the study or exploration of caves. Think “spelunking.” The word was in an article by UNM geologists Polyak et al. on a new age estimate of the Grand Canyon. For many years now, geologists have estimated the formation time of the Canyon at around 6 million years. The new study puts the age at close to 20 million. This may … Continue reading How old is the Grand Canyon? The speleologist knows…