Database for the geologic map of the Washington West 30' x 60' quadrangle, Maryland, Virginia, and Washington D.C.

The database for the Washington West 30- by 60-minute quadrangle covers an area of approximately 4,884 square kilometers (1,343 square miles) in and west of the...华盛顿西30分×60分象限图幅（quadrangle）数据库的覆盖面积约为4884平方千米（1343平方英里），覆盖范围包含……及其以西区域。