SEDIMENT TRANSPORT OVER THE CONTINENTAL-SLOPE OFFSHORE NORTHERN ISRAEL - AN ANALYSIS BY MEANS OF ELECTRON-MICROSCOPY

Seven subsamples from cores collected from the continental terrace off shore northern Israel were examined by TEM and SEM. These samples repr esent different sedimentary environments. The most homogeneous sample was subjected to various stresses, the highest corresponding to the ov erburden loading of a 1000-m-thick sedimentary column. The TEM photomi crographs were quantitatively analyzed using computerized methods. Det rital clay domains, mostly smectite, constitute up to 70% of the sedim ent bulk. Highly compacted silt-sized argillaceous clasts, lumps consi sting of very dense, yet discernible clay domains and varying quantiti es of quartz grains and skeletal carbonate particles are randomly inte rspersed within the clay matrix. The clayey platelets and the argillac eous clasts are of east and north African origin, mostly transported b y the Nile River, and in part by dust storms. The lumps originate from stiff, overconsolidated subbottom sediments detached and transported downslope by slumping. Current-transported quartz grains and skeletal debris from the continental shelf are mixed with these sediments. The analysis of the TEM and SEM photomicrographs supports the model of sed iment dispersal patterns offshore northern Israel which was evaluated from radiographic studies of the cores and other data.