Detailed studies of the intertidal habitats along the Saudi Arabian co
ast conducted 1 year after the Gulf War oil spill as part of the Mt Mi
tchell cruise show that there is a striking correlation between the ne
arshore geomorphology and the persistence of intertidal oil. The most
severely impacted areas studied were several halophyte marsh/algal mat
complexes and mudflats at the heads of sheltered bays, where all the
halophytes were dead and there was no sign of living epibiota in the m
id to upper intertidal areas. The abundant burrows were heavily oiled,
with some containing liquid black oil to depths of over 40 cm. The de
ep penetration of oil into the burrows and probable slow weathering ra
tes of the oil could result in many years of pollution of these shelte
red habitats. The presence of bubble sand, a sponge-like sand deposit
with porosities probably as high at +/-50%, resulted in penetration of
the oil exceeding 40 cm. This deep oil will also remain in the sedime
nt for many years, because of the slow erosion rates that occur in the
se sheltered environments.