METHODS

Samples analyzed in this study are from Holes 1188A and 1188F at Snowcap and 1189A and 1189B at Roman Ruins.

After air-drying, whole-rock mineralogy was determined by X-ray diffractometry. For mineral identification of powered samples from principal investigator K. Lackschewitz, a Philips X-ray diffractometer PW 1710 with monochromatic CuK was used. Qualitative phase identification was performed using MacDiff software (version 4.2.5) from R. Petschick (servermac.geologie.uni-frankfurt.de/Staff/Homepages/Petschick/RainerE.html).

Another set of air-dried powdered samples from principal investigator H. Paulick was analyzed at the XRD Laboratory of the Mineralogical Institute, Freiberg University of Mining and Technology (Germany). Here, a Seifert-Freiberger Präzisionsmechanik GmbH RD7 instrument was used to generate X-ray diffractograms applying monochromatic CuK radiation. Qualitative phase identification was performed using Seifert-Analyze software.

Principal investigator R. Asada analyzed microbiological rock samples for mineral composition. Mineralogical properties were analyzed by a Rigaku RINT2200 X-ray diffractometer with CuK generated at 40 kV and 30 mA. After air-drying the sample, the powders were pressed to fit the diffractometer sample holder. On the other hand, the XRD profiles of clay minerals were obtained from clay fractions deposited on glass slides in order. Furthermore, a fine mist of ethylene glycol (15% in water) was sprayed on dry clay fractions for supplemental information about clay mineral identification.

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