MD iMAP: Maryland Geology - Geologic Formations

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. This file of geologic unit polygons is for educational use. There are known...本数据集为马里兰州（Maryland）iMAP托管服务图层。更多详情请访问 http://imap.maryland.gov。本地质单元多边形文件仅用于教育用途。目前已知存在……