Sulphur and Pyrites

1907 Scientific American  
411 together with seams and masses of sandstone, with lignite, clay beds, and metamorphic granitic porphy rite. The geological area of the Klondike region is there fore composed of a quartz porphyrite for its central section, and is bounded on the north by sericite·mica schist, diabase, limestone, serpentine, and quartz. On the east the Klondike region is bounded by ande site, rhyolite, diabase, conglomerate, sandstone, clay beds, seams of lignite, great peat bogs, and the enor mous "peneplain"
more » ... or mous "peneplain" deposit of Flat Creek "washed grav els," from rocks which are entirely foreign to the local deposit·environment. On the south, the Klondike region is bounded by a great mass of silicified and brecciated Tertiary con glomerates, with andesite, rhyolite, and quartz with quartz porphyrite, together with limestone, altered rhyolite, seams of lignite, clay beds, and sand. :tone. On the west the Klondike region is bounded by a mass of gran ite, with metamorphic granites and quartz porphyrites, together with limestone, rhyolite, andesite, trachyte, agglomerate, and veins of silicite or quartz.
doi:10.1038/scientificamerican12281907-411asupp fatcat:kqfofgyqq5hslepztjdhc3xtj4