Figure 2From: Rare earth element geochemistry of outcrop and core samples from the Marcellus ShaleRare earth element abundance in Marcellus Shale outcrop (open symbols; N = 12 for all analytes) and core samples (closed symbols; N = 6). Geochemical background (Bkgd.), anomalous (A0), strongly anomalous (A1) mass fraction ranges of world black-shales according to Ketris and Yudovich [10].Back to article page