Upper Freeport Coal Bed County Statistics (Geology) in Pennsylvania, Ohio, West Virginia, and Maryland

This dataset is a polygon coverage of counties limited to the extent of the Upper Freeport coal bed resource areas and attributed with statistics on the thickness of...本数据集为覆盖县域的多边形数据集，其空间范围限定于上弗里波特（Upper Freeport）煤层资源区，并附带了相关厚度的统计属性信息。