Batagay megaslump
The Batagay megaslump  (also called the Batagaika crater) is a large pit in Siberia.  It is caused by the permafrost melting.  This megaslump began as a cut on the side of a hill.  It is the largest megaslump in the world. Scientists are interested in the Batagay because it has a natural record of past ecology.  Remains of extinct animals such as the prehistoric steppe bison and cave lion have been recovered.