A geophysical evaluation of the depth and thickness of the capilary fringe in the Holocene sediments of the Nile Delta, Egypt

Abstract EN

The thickness of (lie top agricultural layer in a pan of Pakahliya govcrnorate, Nile: Deltais deters inined clearly by bolh seismic refraction and geoeleotric investigations.

It is recognized that the thicknesses of the (op most, fu st, seismic layer are generally less lhan the thicknesses of the top most, first, geoelectric one.

This layer in both surveys represents the agricultural layer, that is affected by physical nature of both seismic velocities and electric resistivities can be attributed to the interference of the capillary fringe of the soil moisture zone.

The top of this fringe represents the seismic boundary while the boUwm of the fringe represents the clcctric resistivity boundary .

Consequently, the differences between the thickness of the agricultural layer indicated by both seismic refraction and geoelectric surveys are suggested to represent the thicknesses of the capillary fringe in the area of study.

Covered or subsurface drainage systems must take into consideration the depth;and thickness, of -the capillary fringe in the Nile Delta.