TY - RPRT TI - In situ estimation of the effective chemical diffusion coefficient of a rock matrix in a fractured aquifer AU - R.A. Gebrekristos AU - A.M. Shapiro AU - B.H. Usher PY - 2008 DO - 10.1007/s10040-007-0255-0 UR - https://pubs.usgs.gov/publication/70031887 ID - 70031887 ER -