Mark Wilson July 8th, 2011
KURESSAARE, ESTONIA–A dramatic geological site on our last Saaremaa day: the meteorite craters at Kaali. We hiked around the largest crater (shown above) and then visited one of the smaller subsidiary craters nearby (shown below). The main Kaali crater is 110 meters in diameter and about 22 meters deep. The meteorite was between 20 to 80 metric tonnes and was traveling 10-20 km/s. It broke up into pieces 5-10 km above the ground before the multiple impacts. The date of this event is disputed. We have seen ranges in the literature from 4000 to 2700 years ago. Some archaeologists have evidence that an ecological catastrophe followed the impacts with massive wildfires and a drop in crop production for a century. Others think there is a connection between the Kaali event and Baltic mythology. (I think it is a delightful coincidence that the Estonian place name “Kaali” used for this fiery event is coincidentally the same name as the fearsome Hindu goddess.)
To our surprise, the Kaali Museum had a thorough display on the geology of Saaremaa, including this polished cross-section through Nick’s critical Wenlock/Ludlow section.
Our last stop was a virtually abandoned little harbor at Turja on the southeastern coast of the island. It was a nice place for lunch as we contemplated how our fieldwork did not include bears and wolverines (as with our Wooster colleagues in Alaska) or gale-force winds and thick fogs (as experienced by our Iceland friends). We were quite fortunate to gather such excellent geological data with so few such adventures!
Tomorrow we drive to Tallinn to spend a day and a half, and then to Stockholm for a day in the Natural History Museum looking at comparative Silurian material. On Wednesday of next week we fly home.