Figure F4. Representative X-ray diffractogram showing the peaks used for calculations of relative mineral abundance: smectite (001), illite (001), and chlorite (002). Calculations employed the weighting factors of Biscaye (1965). Intensities (counts per second [cps]) of the saddle and peak of the smectite (001) reflection were used to calculate percent expandability, following the method of Rettke (1981). I/S = illite/smectite.

Figure F4. Representative X-ray diffractogram showing the peaks used for calculations of relative mineral abundance: smectite (001), illite (001), and chlorite (002). Calculations employed the weighting factors of Biscaye (1965). Intensities (counts per second [cps]) of the saddle and peak of the smectite (001) reflection were used to calculate percent expandability, following the method of Rettke (1981). I/S = illite/smectite.