* Environmental and Earth Sciences Division, KISR, P.O. Box 24885, 13109 Safat, State of Kuwait
** Geology Department, College of Science, Kuwait University, P.O. Box 5969, 13060 Safat, State of Kuwait
ABSTRACT
More than 100 bottom sediment samples of the Arabian Gulf were collected during a cruise in 1992. The area was covered through 17 traverses in a northeast-southwest direction to the axis of the Gulf. Sedimentological analyses were done for fifty-six samples of reasonable volume.
The recent marine bottom sediments of the Gulf are subdivided into seven textural classes: sand, silty sand, muddy sand, sandy silt, sandy mud, silt, and mud. Most of the study area is covered by muddy sediments, whereas sandy deposits are restricted to the western part (offshore Qatar and the United Arab Emarites) and around islands and bathymetric highs. The counter-clockwise circulation of current from the Indian Ocean probably led to deposition of finer sediments along the eastern (Iranian) side. Sediments along the eastern and northwestern margins are poorly sorted, probably due to the effect of tidal currents, river influx and eolian deposition. Suspension is thought to be the most important process of transportation and deposition, hence low energy conditions prevail in these areas, particularly in the northern part.
Sedimentological characteristics reflect the interaction between autochthonous calcareous fragments mostly of biogenic origin, rock fragments derived from beachrocks and submerged reef flats, and allochthonous terrigenous detritus supplied to the Area by dust storms and river deltas in the north and east.
Based on sediment distribution, the magnitude of bottom currents and the topographic nature of the Arabian Gulf, a north-south sediment transport from the northern part, parallel to the axis of the Gulf, is inferred.