Final unioned files for Yampa coal field resource calculations, northwestern Colorado (yam*fing)

These are shapefiles and final unioned polygon coverages used to calculate coal resources of the A through D coal zones, Yampa coal field, northwestern Colorado....本数据集包含形状文件（shapefile）与最终合并多边形覆盖图层，用于计算科罗拉多州西北部扬帕煤田A至D煤层的煤炭资源量。