Table 4.

Percentage mass loss and amount of fixed carbon after treatments with HCl and HF acids.

	Barnett	Utica	Marcellus
Mass loss post-HCl, wt%	89	93	8
Mass loss post-HF, wt%	63	34	84
Total, %	96	95	85
Fixed carbon post-HCl, wt%	6.6	2.5	6.9
Fixed carbon post-HF, wt%	19	0.4	41