Colluvium Cemented with Sulfur
Sulfur cements a thin mantle of surficial debris along the hillside in the thermally altered volcanics on the east end of Sulfur Lake in the Sunlight Basin, Wyoming.The colluvium is made up of lenses of angular gravels and ocasiional pieces of wood. The sulfur formed through decomposition of hydrogen sulfide which made up part of the gases that rose through irregular fractures iand vented in or just below the colluvium. Alteration of silicate minerals in the volcanics by sulphuric acid produced silicic acid, which in turn deposited the opaline silica that resulted in the white colored altered volcanics. A lot of the colluvium is made up of pieces of the white silicified volcanics. Pine needles at the bottom of the photo give some sense of scale.
References: D. F. Hewitt, 1911, Sulphur Deposits of Sunlight Basin,WY. USGS Bulletin 530-13-23.
Colluvium Cemented with Sulfur
Sulfur cements a thin mantle of surficial debris along the hillside in the thermally altered volcanics on the east end of Sulfur Lake in the Sunlight Basin, Wyoming.The colluvium is made up of lenses of angular gravels and ocasiional pieces of wood. The sulfur formed through decomposition of hydrogen sulfide which made up part of the gases that rose through irregular fractures iand vented in or just below the colluvium. Alteration of silicate minerals in the volcanics by sulphuric acid produced silicic acid, which in turn deposited the opaline silica that resulted in the white colored altered volcanics. A lot of the colluvium is made up of pieces of the white silicified volcanics. Pine needles at the bottom of the photo give some sense of scale.
References: D. F. Hewitt, 1911, Sulphur Deposits of Sunlight Basin,WY. USGS Bulletin 530-13-23.