GEOTECHNICAL PROPERTIES OF BAHMANSHIR SERIES, SOUTHWEST KHUZESTAN, IRAN

Holocene in Southwest Khuzestan is represented by a fluvio-tidal succession termed the Bahmanshir Series which consists of two clayey layers separated by silty sand to silt beds. This paper describes the geotechnical properties of the clayey layers that have wide exposure in the lowlands of the Persian Gulf coast. Studied layers are generally clay sized and consist of a lesser percentage of clay minerals. Most of the clayey layers have intermediate plasticity, and low potential for expansion. The variation of physical and engineering properties of the layers from base to top and along the Bahmanshir River is investigated in this research. The engineering properties of the beds seem to be affected by tidal and river flow currents and totally by their formation sedimentary environments. Links of the geotechnical data with geological features as formation sources in the upstream of the basin, the cementation due to the capillary feature in the floodplain sub-environment and the flocculated texture of clays in the brackish water, have been discussed in this paper. Overall, it is observed that the geotechnical data could be correlated with the geological features of the Bahmanshir Series.