Mercury emissions from background and altered geologic units throughout Nevada

To date there have only been a few studies that measured mercury emissions from background substrate worldwide, and only a small amount of mercury flux data, from background substrate, exists for the Western United States. Because of this, the database of mercury emissions from background units (< 0.1 mg kg(-1) mercury) is incomplete. This study focused on the collection of in-situ mercury flux data from representative lithologic units in Nevada. Measured mercury fluxes from substrate with background mercury concentration throughout Nevada were low ( mean 2.0 +/- 4.1 ng m(-2) hr(-1)), and ranged from - 3.7 to 9.3 ng m(-2) hr(-1). The mean measured mercury flux is slightly higher than those measured from background substrate from various locations throughout the world. The mean mercury flux from in-situ mercury measurements from substrate located near altered geologic units across Nevada was 15.5 +/- 24.2 ng m(-2) hr(-1). These mercury fluxes are higher than the values applied in published global models for naturally enriched geologic units.