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Quantitative analyses of recent benthic foraminiferal assemblages (living and dead) were carried out on the surface sediments of Sulaibikhat Bay. Marked contrast in foraminiferal assemblages between the shallow tidal mudflats and the deep tidal channel and their relation to the extent of pollution were observed. Cluster analysis of quantitative data on the distribution of foraminiferal tests revealed three assemblages that depend mainly on the intensity of pollution; (1) a highly polluted tidal flat assemblage, (2) normal (or less polluted) mud flat assemblage and, (3) tidal channel and subtidal assemblage. The highly polluted assemblage characterized by a drop in species densities (< 100 tests/20 cm(3) sediment) but with high average diversity (5.8 Yule-Simpson Index). The microfauna of the less polluted flat displays relatively lower diversity (4.6) but high density of tests (47.2% of the total picked tests). The most abundant species of this assemblage is Ammonia tepida, displays its maximum density in this assemblage. Ammonia tepida drops in density from 17.12% to 3.07% in the polluted assemblage. Tidal channel foraminiferal assemblages should normally display lower diversities than those of tidal flats, because tidal current in the channels tend to wash away most nutrient materials. However, this is not the case of the present study area which could be due to environmental setting of the Sulaibikhat Bay in which tidal currents bring in exceptionally high amounts of nutrients from Shatt Al-Arab Estuary and in which the tidal flats are strongly and adversely polluted.

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Ce travail concerne le passage Cénomanien-Turonien de quelques affleurements du centre et du nord de la Jordanie. L'étude des microfacies des Formations de Hummar et de Schueib (subdivisions del" ' Ajlun Series") de trois coupes stratigraphi-ques mesurées à Ajlun, à L'm El-Dananir et à Karak suggère une sédimentation marine de faible profondeur pour la Formation de Hummar qui est d'âge cénomanien. La Formation de Shueib est généralement d'âge turonien inférieur et dénote une sédimentation en mer relativement profonde à topographie compliquée (présence de turbidites), suggérant que des mouvements tectoniques, exprimés par la formation de failles et de plissements, avaient été actifs vers la fin du Cénomanien.