Named after Vasily Vasil'evich Dokuchaev - Russian soil scientist; founded modern genetical soil science (1840-1903).
Vasily Vasili'evich Dokuchaev was a Russian geologist who is credited with laying the foundations of soil science. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On Mars large craters are named after deceased scientists, writers and others who have contributed to the lore of Mars. Small creaters (less than 60km) are named after small towns and villages.