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Forty-three ichnospecies belonging to 30 ichnogenera are described from the Upper Jurassic Argiles de Saïda Formation (north-western Algeria), which consists of mixed shallow marine siliciclastic-carbonate sediments. The ichnological analysis reveals that the majority of the ichnoassemblages are represented by non-graphoglyptid traces dominated by Bergaueria isp., Ophiomorpha isp., O. rudis, Neonereites biserialis, N. triserialis. Furthermore, Chondrites isp., Palaeophycus isp., Phycosiphon isp., Planolites isp., Protovirgularia isp., Scolicia isp. and Thalassinoides isp. are common ichnotaxa. Ancorichnus isp., Archaeonassa isp., Gordia isp., Helminthoidichnites isp., Helminthopsis isp., Nereites isp., Ophiomorpha annulta, Oravaichnium isp., Oravaichnium hrabei, Protovirgularia dichotoma, Rutichnus rutis, Thalassinoides suevicus are rare, whereas, Chondrites targionii, Nereites irregularis, Neonereites uniserialis, Ptychoplasma excelsum, Spongeliomorpha isp., Taenidium isp., Taenidium serpentinum, ?Tubulichnium isp. and Zoophycos isp. are rare to scarce ichnotaxa. The graphoglyptid assemblage has very low diversity with only three ichnotaxa which are Megagrapton isp., Megagrapton submontanum and Scolicia strozzii. The described ichnoassemblages are assigned to the Cruziana to Cruziana-Nereites ichnofacies transition. [ABSTRACT FROM AUTHOR]

Three main facies associations FA-1 to FA-3 occur in the Oxfordian Argiles rouges de Kheneg Formation in northwestern Algeria. They correspond respectively to the deeper part of a mixed siliciclastic-carbonate shelf, upper shoreface and offshore transition-lower offshore. The trace fossil association of the Argiles rouges de Kheneg Formation contains fifteen ichnogenera and is moderately diverse for the Upper Jurassic. The formation contains diverse and abundant deep water or dominantly deep water trace fossils (i.e. Belorhaphe, Chondrites, Helminthopsis, Nereites, Megagrapton). They indicate that a part of the formation was deposited in offshore transition to lower offshore environments. [ABSTRACT FROM AUTHOR]

The Berriasian–Valanginian succession cropping out in the Ouarsenis Range (northwestern Algeria) consists of ammonite-bearing, marlstone-limestone alternations, herein divided into four informal units (A to D) at the Aïn El Hadjela section. These lithostratigraphic units encompass five standard Mediterranean ammonite zones of late Berriasian to late Valanginian age. In this study nine ichnotaxa are documented: Chondrites intricatus, Palaeophycus isp. , Planolites isp., Rhizocorallium commune, Thalassinoides isp.; Thalassinoides suevicus , Tisoa siphonalis , Zoophycos isp. and Zoophycos brianteus , reported for the first time from the early Cretaceous of Algeria. These traces are characteristics of the Zoophycos ichnofacies, representing deep and oxygen-restricted environments. This ichno-association together with litho-biofacies contents are suggesting deepening from deeper part of platform to the basin environment as identified in previous studies of the same time interval through the Mediterranean region. • The Berriasian–Valanginian succession of the Ouarsenis Range (northwestern Algeria) has been studied. • The succession suggests a deepening from deeper part of platform to basin environment. • Ichnological features indicate the Zoophycos ichnofacies and reveal oxygen-restricted conditions. • The succession encompasses five standard Mediterranean ammonite zones of late Berriasian to late Valanginian age. [ABSTRACT FROM AUTHOR]

The Messinian shallow marine diatomaceous deposits (Tripoli Diatomite Formation) of the Lower Chelif basin (northwestern Algeria) display a moderate diversity and high abundance of decapod crustacean trace fossils, preserved mainly as endichnia, epichnia and hypichnia. These deposits consist of diatomites intercalated by diatomaceous marls and rarely micritic limestones, containing nine ichnospecies from seven ichnogenera, dominated by domichnion trace fossils (Diplocraterion isp., Ophiomorpha isp., O. nodosa , Palaeophycus isp., Planolites isp., cf. Skolithos isp., Spongeliomorpha isp., Thalassinoides isp. and T. suevicus). Two ichnofabrics have been identified, represented by the Ophiomorpha ichnofabric which characterises the diatomaceous deposits of the Djebel Murdjadjo carbonate platform, and the Thalassinoides ichnofabric in the Tessala–Beni Chougrane carbonate platform. The ichnological, palaeontological and sedimentological data confirm that the trace fossil bearing diatomaceous beds were deposited in a nearshore shallow sea under moderate-to high-energy conditions constituting a part of the Skolithos ichnofacies in the Djebel Murdjadjo carbonate platform, and the Cruziana ichnofacies in the Tessala–Beni Chougrane carbonate platform. The comparison between shallow- and deep-marine diatomites indicates a regressive sequence in the deep diatomites, with abundant Chondrites and Zoophycos at the base of the succession grading downward into Thalassinoides -dominated trace fossil assemblage in the uppermost part, which is similar to the shallow-tier trace fossils of the two carbonate platforms, represented by Ophiomorpha -dominated ichnoassemblage in the Djebel Murdjadjo carbonate platform, and by Thalassinoides -dominated ichnoassemblage in the Tessala–Beni Chougrane carbonate platform. • Ichnological analysis was conducted on Messinian shallow marine diatomaceous deposits (Tripoli Diatomite Formation) from the Lower Chelif basin, northwestern Algeria. • The ichnoassemblage is composed of Diplocraterion isp., Ophiomorpha isp., O. nodosa , Palaeophycus isp., Planolites isp., cf. Skolithos isp., Spongeliomorpha isp., Thalassinoides isp., and T. suevicus. • This ichnoassemblage is dominated by dwelling structures (domichnia) produced mainly by decapod crustaceans. • Two ichnofabrics characterise the succession. [ABSTRACT FROM AUTHOR]

In this research study, 27 ichnospecies belonging to 18 ichnogenera are described for the first time from the lower Miocene Tiaret Marl Formation (north-western Algeria), which consists of thin-to medium-bedded sandstones and marlstones, representing deep-sea fan facies. The sandstones contain the following ichnotaxa: Cardioichnus isp., cf. Chondrites isp., Ophiomorpha isp., Ophiomorpha annulata, Ophiomorpha rudis , Palaeophycus isp., cf. Planolites isp., Planolites montanus, Zoophycos isp., Tisoa siphonalis , Helminthorhaphe isp., Scolicia isp., Scolicia prisca, Scolicia vertebralis , Cosmorhaphe isp., Desmograpton isp., Gordia isp., Helminthopsis isp., Nereites isp. , Tubulichnium cf. incertum , Urohelminthoida appendiculata, cf. Megagrapton isp., Paleodictyon minimum, P. strozzii, P. majus, P. (Glenedictyum) miocenicum and P. maximum. The given ichnoassemblage is recorded for the first time from the Miocene of Algeria and assigned to the Nereites ichnofacies, which is typical of marine bathyal depth. • The lower Miocene Tiaret Marl Formation has been divided into 2 units. • The environment corresponds to deep-sea fan. • Several trace fossils from Tiaret Marl Formation are recorded for the first time from Algeria. • The studied ichnoassemblage corresponds to the Nereites ichnofacies. [ABSTRACT FROM AUTHOR]