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Paul H. Briggs

Publications and source records attributed to Paul H. Briggs.

At least 73 records · Page 4Linked to original sources
USGS1995

The effect of acidic, metal-enriched drainage from the Wightman Fork and Alamosa River on the composition of selected wetlands in San Luis Valley, Colorado

The biogeochemistry of selected wetlands in the San Luis Valley, Colorado, was examined to assess the effect of acidic, metal-enriched water draining mineralized areas near and around the Summitville Mine. The sampling protocols, analytical methods, and chemical composition of water and stream bed sediment from the Wightman Fork and Alamosa River as well as water, surface sediment or cores, and rooted aquatic vegetation from wetland sites within and west of the Alamosa National Wildlife Refuge are presented. The data indicate that As, Co, Cr, Cu, Ni, and Zn are tracers of drainage from mineralized areas around the Summitville Mine. Sediments and aquatic plants in wetlands in the San Luis Valley that receive surface water from the Alamosa River tend to have larger concentrations of certain tracer elements (e.g., Co and Cu) than wetlands that receive water from other sources. Larger concentrations of Cu, Ni, and Zn in the sediments of wetlands receiving Alamosa River water appear to be related to the presence of larger amounts of Fe oxyhydroxides. However, there is little to no variation in the concentrations of tracer elements with depth in wetlands that receive Alamosa River water. This observation suggests that the geochemistry of these wetlands has not been significantly affected by recent mining activities at the Summitville Mine.

Colorado↗
USGS1995

Pink topaz from the Thomas Range, Juab County, Utah

The Thomas Range is world-famous for its production of topaz Al2SiO4(F,OH)2, occurring in lithophysal cavities in rhyolite. Topaz Valley, at the southern end of the range, is perhaps the single most famous locality. While fine-quality, sherry-orange crystals to 5 cm or more in length occur at various localities, pale to medium pink crystals were first reported from the Thomas Range in 1934. The cause of the unusual coloration, unknown for 60 years, is now believed to be substitution of Mn3+ ?? Fe3+ for Al3+. -Authors

Mineralogical Record↗