The Llewellyn Formation is a mapped bedrock unit in eastern Pennsylvania. It was previously known as the "coal measures" and the post-Pottsville rocks. The formation is named for the community of Llewellyn in Schuylkill County.
The Llewellyn Formation is a mapped bedrock unit in eastern Pennsylvania. It was previously known as the "coal measures" and the post-Pottsville rocks. The formation is named for the community of Llewellyn in Schuylkill County. (en)
The Llewellyn Formation is a mapped bedrock unit in eastern Pennsylvania. It was previously known as the "coal measures" and the post-Pottsville rocks. The formation is named for the community of Llewellyn in Schuylkill County. (en)