Geochemical mass-balance relationships for selected ions in precipitation and stream water, Catoctin Mountains, Maryland ( USA) .

Abstract

Precipitation and stream water were sampled weekly for quantity and chemical composition in two small watersheds in the Catoctin Mountains of central Maryland. Both watersheds are underlain by metabasaltic rock consisting of chlorite, albite, epidote, and actinolite and minor amounts of calcite and quartz. Precipitation recorded in 1983 was approx 60% greater than in 1982; however, the discharge of streams draining both watersheds, which accounted for 50% of precipitation input, remained relatively constant. Hydrogen, sulfate, and nitrate were the major ions in precipitation, whereas calcium, magnesium, and bicarbonate were the major ions in stream water. -from Authors