USGS Coastal and Marine Geology Program > Pacific Coastal & Marine Science Center > Research Projects > Coastal Aquifer Project: Submarine Groundwater Discharge > Methods & Tools > Autonomous, Electromagnetic Seepage Meter to Study Coastal Groundwater/Surface-water Exchange
"An autonomous, electromagnetic seepage meter to study coastal groundwater/surface-water exchange" is a four-page full-color pamphlet detailing the use of a "state-of-the-art electromagnetic flow meter that enables rapid, autonomous, bi-directional measurements of fluid exchange rates across the sediment/water interface."
See the whole publication online, or download a printable copy (1 MB PDF) from: sofia.usgs.gov/publications/ofr/2004-1369/.
Five-day time series of (A) bottom water 222Rn activities (disintegrations per minute per Liter, dpm/L), (B) bidirectional electromagnetic (EM) seepage meter results (centimeter per day, cm/d); the zero discharge line is shown for reference, and (C) bottom water conductivities (milliSiemems per centimeter, mS/cm) collected from the top of an electro-magnetic (EM) seepage meter dome. The reference line in (C) denotes the mean conductivity (40.7 mS/cm) of the bottom waters.