• an environment of moderate depth, which probably corresponds to the external part of the neritic zone, or eventually to the upper part of the continental slope. The sedimentary basin had, at that time, a rather restricted connection with the open deep sea, as shown by the fact that Myctophids are rather scarce in the collected material. It should be emphasized that the Tortonian fish fauna from Gavdos exhibits a striking similarity with that from Ierapetra [5,10,16,28], where the genus Bregmaceros Thomp- son is also predominant (more than 70% of the col- lected material), whereas the genera Lepidopus Gouan and Syngnathus L. are also present.

• sediments deposited in an estuarine environment and shallow marine sands rich in Heterostegina, echinoderms and molluscs [24]. The lower part of the marine section is characterized by a high benthic/planktonic foraminifera ratio, which is indicative of a close proximity to the shore. Above the marine sands takes place an alternation of hemipelagic marls and brownish laminated beds (the so-called ‘sapropels’), which are numbered from M1 to M96 [17,20], although the Metochia B section ends with bed M 55. The upward decrease of the benthic/planktonic ratio suggests a gradual deepening [24] starting from the first sapropel level (M1), which is also suggested by the correlative replacement of marine sands by hemipelagic marls. In the lower part of the Metochia B section, five successive turbiditic sequences (M7 to M11) occur within or completely replace the laminated intervals. According to Ekdale et al. [15], the occurrence in these sequences of the ichnofossils Zoophycus and Chondrites is indicative of restricted aerobic condi- tions. This is confirmed by the abundance of plant and wood remains in these levels. The fish-fauna which is preserved as articulated skeletons was found in the lower part (M16–M22 cycles) of the Metochia B section.