Advection of Pore Fluids Through Sediments in the Equatorial East Pacific

Measurements of the ratio of helium-4 to helium-3 and of calcium ion in the pore waters of sediments at two locations in the eastern equatorial Pacific indicate that solution advection is occurring through the sediments. Both the helium ratio and the calcium ion profile yield velocity values for advective flow of about 20 centimeters per year. Mass balance constraints are also consistent with the interpretation presented. Flow appears to be occurring thorugh relatively thick sediments, on the order of 300 meters.