Measurement of Cl⁻ : Br⁻ Ratios in the Porewater of Clay-Rich Rocks—A Comparison of the Crush-and-Leach and the Paper-Absorption Methods

Table 1

Mineralogical and Physical properties.

	Michigan Basin			Opalinus Clay			Lorraine Group
	Queenstown	Georgian Bay	Blue Mountain	Sandy facies	Carbonate sandy facies	Shaly facies
	Mineral composition (wt.%
Calcite	8–57	3–31	4–11	4–22	21–59	12–36	8
Dolomite	9–3	2–41	2–8	0–6	0-1	0-1	7
Quartz	4–17	12–46	30–47	13–45	5–29	13–26	27
Clay	17–60	23–70	27–31	25–66	8–48	36–60	46
Feldspar	–	2–6	–	2–5	3	1-2	10
	Number of core samples
Paper absorption	3	1	2	4	–	2	4
Crush and leach	3	1	2	7	1	8	4
	Hydraulic conductivity (m/s
	1.1 × 10^−14–1.0 × 10^−13			2.0 × 10^−14–6.0 × 10^−13			N/A
	Porosity (accessible loss%
	6-7			12–15			N/A
	Ionic strength (mol/L
	8.2			0.4			N/A

[43]; [44, 45]; Clark, Matray, and Waber: BDB-1 borehole investigation, unpublished; [37]; [46]; [47]; [30]; [48, 49]; N/A = not available.