Darker colors on the map indicate greater thickness of selected shale. Gray = no known Marcellus; yellow = 0-25ft.; orange = 26-50ft.; pink = 51-75ft.; violet= 76-100ft.; black = over 100ft.
- Credit: N/A
- Ownership: West Virginia Geological and Economic Survey
- Publication: N/A
- Editor: N/A
- Publisher: N/A
