2011 Wells Drilled By County as of 11/30/2011
| County | Non Marcellus | Marcellus | Total |
| Allegheny | 26 | 5 | 31 |
| Armstrong | 27 | 32 | 59 |
| Beaver | 6 | 6 | |
| Blair | 1 | 1 | |
| Bradford | 373 | 373 | |
| Butler | 14 | 35 | 49 |
| Cambria | 7 | 3 | 10 |
| Cameron | 6 | 6 | |
| Centre | 6 | 6 | |
| Clarion | 47 | 8 | 55 |
| Clearfield | 1 | 56 | 57 |
| Clinton | 30 | 30 | |
| Columbia | 1 | 1 | |
| Crawford | 13 | 13 | |
| Elk | 19 | 18 | 37 |
| Erie | 8 | 8 | |
| Fayette | 3 | 36 | 39 |
| Forest | 126 | 126 | |
| Greene | 19 | 100 | 119 |
| Indiana | 55 | 22 | 77 |
| Jefferson | 7 | 14 | 21 |
| Lackawanna | 1 | 1 | |
| Lawrence | 2 | 2 | |
| Lycoming | 2 | 258 | 260 |
| McKean | 220 | 17 | 237 |
| Mercer | 29 | 29 | |
| Potter | 4 | 16 | 20 |
| Somerset | 8 | 8 | |
| Sullivan | 19 | 19 | |
| Susquehanna | 2 | 183 | 185 |
| Tioga | 8 | 239 | 247 |
| Venango | 50 | 1 | 51 |
| Warren | 138 | 138 | |
| Washington | 7 | 144 | 151 |
| Westmoreland | 28 | 63 | 91 |
| Wyoming | 1 | 54 | 55 |
| Total | 867 | 1,751 | 2,618 |