The Zabuk Formation of the Derik Group exposed over much of south-eastern Turkey presents a succession composed of shallow marine and fluvial siliciclastic sedimentary rocks. The Lower Cambrian assemblages containing abundant anemone-style trace fossils are known from most major palaeocontinents such as Laurentia, Baltica, and Gondwana. These have possible affinities with semi-infaunal dwelling anemones on siliciclastic mid-latitude shelves of West Gondwana in early Fortunian deposits. Among them is Bergaueria, characterized by plug-shaped burrows as exemplified by Bergaueriaperata, that is, a characteristic trace fossil of the Cambrian globally.
La formation Zaduk du groupe Derik qu’on observe dans une grande partie de la Turquie du Sud-Est présente une succession composée de roches sédimentaires siliciclastiques fluviales ou marines de faible profondeur. Les assemblages du Cambrien inférieur qui renferment d’abondantes traces de fossiles de type anémone sont connus dans la plupart des paléocontinents majeurs, tels Laurentia, Baltica et Gondwana. Celles-ci semblent avoir des affinités avec celles des anémones semi-endofauniques des dépôts Fortunien inférieur des plates-formes siliciclastiques de moyenne latitude du Gondwana occidental. Parmi ces traces, celles de Bergaueria sont caractérisées par une forme de type cavité avec bouchon, comme l’illustre Bergaueriaperata à trace fossile caractéristique du Cambrien à l’échelle globale.
SE Turkey, Gondwana, Lower Cambrian, Palaeoenvironment, Trace fossils, BergaueriaTurquie du Sud-Est, Gondwana, Cambrien inférieur, Paléoenvironnement, Traces fossiles, BergaueriapresentedHandled by Annalisa Ferretti.Introduction
Precise affinities of complex infaunal behavioural patterns are problematic, such as those that first appeared with the “Small Shelly Fossils” (SSF), trilobites, brachiopods, and hyoliths (Geyer and Landing, 2016). Among these, trilobites have been increasingly used for biostratigraphic correlation of the Cambrian System. However, Early Cambrian pre-trilobite bearing successions with trace fossil assemblages can provide good alternative index fossils in the regional and global stratigraphic subdivisions of the Cambrian (Peng et al., 2012). A characteristic trace fossil was first described under the name PhycodespedumSeilacher, 1955 and is now known either as Treptichnuspedum (Jensen, 1997) or Trichophycuspedum (Geyer and Uchman, 1995) depending on the interpretation of its mode of formation (Geyer and Landing, 2016).
Numerous studies have been conducted on the Cambrian shelf sediments of the Proto-Tethyan Ocean to characterize their architecture, facies, and discontinuities. Cambrian units of different lithotypes that form parts of thick Palaeozoic sedimentary successions of the North Arabian Peninsula (Fig. 1a), are represented by the tidal quartz-arenite, which include the Cruziana ichnofacies with Dimorphichnusquadrifidus in the middle part of the Zabuk Formation (Fig. 1b) (Ghienne et al., 2010). Similar distributions of trace fossils can be documented from other Cambrian tide-dominated successions. For example, Erdoğan et al. (2004) documented several ichnotaxa of the Cruziana ichnofacies in tidal successions of the Early Cambrian in Taurus Range (south-western Turkey).
Early Cambrian trace fossils such as Bergaueria (B. sucta, B. perata, B. radiata, B. major and B. hemispherica) from several palaeocontinental margins have been attributed to possible actiniarian activity. We present here the first data on plug-shaped burrows (Bergaueria) in the Derik Group which shed new light on the Cambrian life recorded in rocks of the south-eastern Turkey. The new records from the lower part of the Zabuk Formation provide important knowledge on the diversity of Early Cambrian trace fossils (Fig. 1b).
Geological setting
A Cambrian series of clastic rocks with interbedded carbonates is exposed in south-eastern Turkey and constitutes a west-east trending outcrop belt (Fig. 1a). A thick pile of Early Cambrian marine siliciclastics from the basal Zabuk Formation, with Terreneuvean fluvial sediments were deposited in the northern margin of the Arabian Plate of the West Gondwana in the stable platform regime (Ghienne et al., 2010 and Lamsdell et al., 2013). The Lower Cambrian (corresponding to the Terreneuvian and Cambrian Series 2; Peng et al., 2012) of the Derik–Mardin region is represented by a 584–830 m thick siliciclastic series (Kellog, 1960). This complex lithologic framework led to the recognition of several informal units (Dean, 1975). These units have been revised by Ghienne et al. (2010) because of detailed mapping and facies distinction; their lithostratigraphic units are based on the predominance of coarse and fine terrigenous sediment associations. The Neoproterozoic “Derik volcanics” unconformably underlies the Lower Cambrian sequence, which consists of fine to coarse sandstones of the Zabuk Formation. The Koruk Formation conformably overlies the Zabuk Formation. It is composed of dolomites and grey nodular limestones (Fig. 1b). Interbeds of grey, micaceous and clayey limestones occur especially in the upper levels around the highest 7 m, and are followed by brownish silty shales of the basal Sosink Formation. The Late Cambrian Sosink Formation conformably overlies the Koruk Formation and is composed of shale and sandstones with trilobites (Mergl et al., 2018).
The new records of plug-shaped burrows reported here come from the lower part of the Zabuk Formation and are positioned between overlying strata of the arkosic, cross-bedded sandstones, and the underlying strata of siltstones with rippled thin sandstone beds (Fig. 2b). In the field, bedding planes of strata can be seen that consist of red and purple coloured sandstone beds intercalated with thin sandy shales. Sandstones are either structureless or display cross-stratification, parallel lamination, ripple cross-lamination, ripple marks and shale intercalations.
The non-arthropod ichnogenera were discovered during fieldwork undertaken by us in August 2015. Although a part of the ichnotaxa described below are generally associated with sedimentary structure that could be worked in situ in the field because of their position in hard strata in outcrops (Fig. 2a, b), they were only accessible with difficulty.
Methodology
Study of lithofacies has been carried out bed by bed by İsmail Ömer Yılmaz in the field using cm-scale observation and description made by using visual estimation charts. Fossil analysis and sampling have been carried out by İzzet Hoşgör in the field and identifications of ichnotaxa have been made by Dirk Knaust.
Systematic ichnology
Ichnogenus BergaueriaPrantl, 1945
Type ichnospecies Bergaueria perataPrantl, 1945
Bergaueria perataPrantl, 1945
(Fig. 2e–ı)
Material. In situ specimens and field observations preserved as positive hyporeliefs in fine- to very fine-grained sandstone. In the field, 109 burrows were examined and all of them exhibit a hemispherical shape (Fig. 2a, b). We constrain our interpretations to the following taphonomic scheme (Fig. 2a): recognizable, but poorly preserved specimens (44%); poorly preserved specimens 29%; and well-preserved specimens (27%).
Stratigraphical distribution. Lower part of the Zabuk Formation. Fortunian–Stage 2.
Description. Hypichnial, sandstone-filled, regular, wider than deep, cylindrical plug-shaped structure, slightly smoothly conical basal part. Shallow, hemispherical burrows with hemispherical lower termination display a small central depression (Fig. 2e-ı). The whole structure is 7–14.5 mm in diameter, 4–9 mm high, with an apical depression, which is 2–3 mm wide. The depth of the figured specimen is 3 mm (Fig. 2f). Numerous specimens of different diameter may co-occur on the same bedding plane. This structure shows smooth, unornamented side margins.
Remarks. Previous work has assumed anemone producers for the ichnogenera Bergaueria, Conichnus, Conostichus and Dolopichnus (Laevicyclus, according to Knaust, 2015) (e.g., Alpert, 1973 and Prantl, 1945). The hemispherical and slightly conical shape of the basal part relates the described specimens to the typical Bergaueria perata from the Upper Ordovician Letná Formation of Czech Republic (Prantl, 1945, p. 52–53, pl. 1, figs. 1–2), the Lower Cambrian of India (Singh et al., 2014, p. 1674, figs. 8e, 9e, 10b; Sudan and Sharma, 2001, p. 162, pl. 1. I), Canada (Pemberton and Magwood, 1990, p. 437, figs. 2.1–2.3, 3.3), Sweden (Jensen and Grant, 1998, fig. 5c) and the Upper Cambrian of Poland (Radwański and Roniewicz, 1963, p. 271, pl. 9, figs. 1–3) and to trace fossils from the Lower and Middle Cambrian of the South American part of Gondwana (Pickerill, 1989a). The Goczałkowice Formation of southern Poland contains anemone-style trace fossils assignable to Bergaueria (32–56 mm in length), Conichnus (15–76 mm in length), and Conostichus (35–40 mm in length) in lower and upper shoreface deposits (Pacześna, 2010). The trace fossil most closely similar to Bergaureria is ConostichusLesquereux, 1876, from Early Cambrian successions of Baltica and Laurentia also believed to be the casts of actinian burrows (Alpert, 1973 and Pacześna, 2010). The main morphological differences indicate that Conostichus is larger (average size about 65 mm in height and 45 mm in diameter) and more conical than cylindrical or hemispherical in shape (Chamberlain, 1971 and Pemberton et al., 1988). B. perata differs from B. radiata (Pemberton and Magwood, 1990, p. 438, figs. 2.1, 2.4) and B. hemispherica (Pemberton and Magwood, 1990, p. 437, figs. 2.1, 3.1–2) by the absence of faint radial ridges. B. perata is morphologically close to Guanshanichnus isp., which is a knob-shaped vertical burrows (Weber et al., 2013, p. 226, fig. 18a) from the Lower Cambrian (Stage 2) of the Malyi Karatau area (SE Kazakhstan). However, B. perata tends to be hemispherical in shape with a deeper central depression.
DiscussionPalaeoecological and palaeoenvironmental aspects
In the majority of the Phanerozoic settings, the mixed layer (typically 8 to 10 cm thick) is affected by biological activities, most notably by metazoan bioturbation (Bromley, 1996). Hagadorn and Bottjer (1999) pointed out that during the Precambrian–Cambrian transition and Cambrian period, the sedimentologic “pendulum” shifted (triangular diagrams in Fig. 3a) towards increasing metazoan influence, and by the post-Ordovician, the remarkable factors affecting marine siliciclastic successions were physical and metazoan processes. It is widely assumed that surface traces have a low preservation potential in marine settings (Buatois et al., 2017).
Hemispherical, conical to subconical, and cylindrical to subcylindrical burrows are included in the vertical plug-shaped burrows category (Buatois et al., 2017). These morphologies represent resting or dwelling trace fossils mostly produced by actinarian or ceriantharian sea anemones (Buatois et al., 2017 and Pemberton et al., 1988).
The greatest diversity of Cambrian trace fossils may be found on bedding planes heterolithic sediments showing moderately thin, generally centimetre-scale, often sharp-based sand and siltstone beds (Jensen et al., 2005). According to Pacześna (2010), the plug-shaped burrows related to the activity of sea anemones are characterized particularly by the columnar shape, ornamentation or lining of the burrow margin and sculpture of the basal part. Orłowski and Radwnański (1986) discussed the sea-anemone burrows of the Middle Devonian shallow-water succession in the Holy Cross Mountains (Central Poland), documenting the presence of abundant, gregarious occurrences of the swarmy populated by sea anemones in structureless sand.
The action of burrowing anemones is recorded in morphological details of Bergaueria. Dwelling sea anemones are potential producers of Bergaureria-like traces in modern sandy bottom (Knaust, 2017) (Fig. 3b). These trace makers have fairly narrow grain size preferences and the majority live in sandy substrates. Sea anemones that burrow through the mud-sand interface may leave trace fossils that are preserved on the base of the sandstone (Chamberlain, 1971). Bergaueria preserved on thin sand layers represent shallow burrows, which were generally no more than a few centimetres in deep (Knaust, 2017 and Mata et al., 2012). Burrows in mud may be scoured by currents and filled by sand (Fig. 3b).
Palaeogeographical approach
Early Cambrian trace fossils have been described from various localities worldwide. However, a majority of them are restricted either to siliciclastic facies or to a periphery of calcareous facies. With the beginning of the Cambrian period, highly developed and complex faunas from the shallow shelf areas of Laurentia, Baltica and Gondwanaland, consisting of (McIlory and Logan, 1999 and Weber et al., 2007) rich Early Cambrian ichnoassemblages, occur in Sweden (Jensen, 1997), NW Argentina (Mángano et al., 2005), NW Canada (MacNaughton and Narbonne, 1999), Namibia (Geyer and Uchman, 1995), South Spain (Vintaned et al., 2006), Czech Republic (Central Bohemia, Mikuláš, 1995 and Mikuláš, 2000), India (Spiti Basin, Parcha and Pandey, 2011, Sudan and Sharma, 2001; Bikaner–Nagaur Basin, Pandey et al., 2014; Rajasthan Basin, Singh et al., 2014), SE Kazakhstan (Weber et al., 2013) or South China (Weber et al., 2007), with more than 42 ichnogenera for the Fortunian and 43 ichnogenera for the Stage 2 (Mángano and Buatois, 2014).
Both the wide palaeogeographic distribution and extensive stratigraphic range of Bergaueria suggest that suitable environmental conditions (low carbonate soft substrates) for production and preservation of plug-shaped burrows were relatively widespread over several palaeocontinental margins of Baltica, Gondwana and Laurentia and persisted during the Early Palaeozoic (Fig. 3c). Nine ichnospecies of BergaueriaPrantl, 1945 (Bergaueria perata, B. major, B. hemispherica, B. sucta, B. radiata, B. phallica, B. elliptica, B. langi and B. prantli) have previously been recognized in the Lower Palaeozoic of these regions (Alpert, 1973, Buatois et al., 2017, Gibert et al., 2011, Jensen and Grant, 1998, Knaust, 2004, Knaust, 2017, Mángano and Buatois, 2004, Mángano et al., 2013, Mata et al., 2012, McIlroy and Braiser, 2016, Mikuláš, 1993, Mikuláš, 2000, Orłowski, 1989, Orlowski and Źylińska, 1996, Pacześna, 2010, Palij, 1976, Pemberton and Magwood, 1990, Pickerill, 1989a, Pickerill, 1989b, Radwański and Roniewicz, 1963, Seilacher, 2007, Stachacz, 2016, Sudan and Sharma, 2001, Vintaned et al., 2006 and Weber et al., 2007).
Although there are many important younger records (e.g., from the late Anisian Middle Muschelkalk; Knaust, 2007), Bergaueria perata ranges mostly from the Early Cambrian (Fortunian) to the Late Silurian (Ludlow) and represents a stratigraphic indicator in mid-latitude regions of Baltica in Sweden and Poland (Jensen and Grant, 1998, Orlowski and Źylińska, 1996, Pacześna, 2010, Seilacher, 2007 and Stachacz, 2016) (Table 1). It occurs also in Gondwana in Czech Republic, Spain, SE Turkey, Iran, India, or NW Argentina (Bayet-Goll and Carvalho, 2017, Mángano and Buatois, 2004, Mikuláš, 2000, Prantl, 1945, Radwański and Roniewicz, 1963, Sudan and Sharma, 2001 and Vintaned et al., 2006; this study) and in Laurentia (North America) (Alpert, 1973, Pemberton and Magwood, 1990, Pickerill, 1989a, Pickerill, 1989b and Seilacher, 2007) (Fig. 3c). Regional lithostratigraphic similarities (mainly siliciclastic facies) indicate that SE Turkey shared a common Cambrian and Ordovician depositional history with Spain, central Bohemia, Jordan, Libya and western India, along the Proto-Tethyan margin of Gondwana (Fig. 3c; Amireh et al., 1994). The Early Cambrian Bergaueria perata described in this paper is the first ichnospecies of Bergaueria from the northern Arabian Plate (Mardin–Derik, SE Turkey) and it represents the plug-shaped burrows from the northern Gondwana.
Conclusions
Knowledge of the Early Cambrian sedimentary history of the western Gondwana is advanced by new data from the south-eastern Turkey. In comparison to other geologic periods, ichnologic reports from Cambrian shallow marine siliciclastic successions are relatively sparse, whereas this study from the northern margin of the Arabian Plate demonstrates a behaviour of anemones from the Early Cambrian successions of the Mardin–Derik area. The Zabuk Formation gives an idea of the semi-infaunal dwelling anemones that lived in the northern Arabian siliciclastic mid-latitude shelves of West Gondwana took place since the early Fortunian. These cnidarians proliferated in shallow arenaceous shelves during the Terreneuvian in all palaeocontinents except for the tropical South China. Bergaueria represents an important part of Early Cambrian non-arthropod communities, and they can be easily found in fine-grained clastic sediments from across the Cambrian palaeocontinents. In the West Gondwana, the carbonate sedimentation was unfavourable for their mode of life. Sessile cnidarians spread from the tropical to subtropical areas to low latitudes, but always preferred a siliciclastic sea floor during the Early Palaeozoic.
Acknowledgements
We would like to thank Dirk Knaust and Birendra P. Singh for identification and discussion on the presented Bergaueria perata, and for the constructive comments that have helped to improve the paper. We are grateful for detailed and helpful reviews by Annalisa Ferretti, Radek Mikuláš and Alfred Uchman. We especially thank Alison M. Murray for linguistic review and comments.
AlpertS.P.Bergaueria Prantl (Cambrian and Ordovician), a probable actinian trace fossilJ. Paleontol.471973919–924AmirehB.S.SchneiderW.AbedA.M.Evolving fluvial-transitional-marine deposition through the Cambrian sequence of JordanSediment. Geol.89199465–90Bayet-GollA.CarvalhoC.N.Sedimentological and ichnological characteristics of deltaic and non-deltaic successions of the Lower Ordovician of Shahmirzad area, Alborz Mountains of northern IranBollettino della Società Paleontologica Italiana562017127–151BromleyR.G.Trace fossils: biology, taphonomy and applications1996Chapman and HallLondon1–361BuatoisL.WisshakM.WilsonM.A.MánganoM.G.Categories of architectural designs in trace fossils: a measure of ichnodisparityEarth Sci. Rev.1642017102–181ChamberlainC.K.Morphology and ethology of trace fossils from the Ouchita Mountains, Southeast OklahomaJ. Paleontol.451971212–246DeanW.T.Cambrian and Ordovician correlation and trilobite distribution in TurkeyFossils Strata51975353–373DeanW.T.MartiniF.MonodO.GünayY.KozluH.BozdoganN.Precambrian? and Cambrian stratigraphy of the Penbegli-Tut inlier, southeastern TurkeyGeol. Mag.134199737–53ErdoğanB.UchmanA.GüngörT.ÖzgülN.Lithostratigraphy of the Lower Cambrian metaclastics and their age based on trace fossils in the Sandıklı region, southwestern TurkeyGeobios372004346–360GeyerG.LandingE.The Precambrian–Phanerozoic and Ediacaran–Cambrian boundaries: a historical approach to a dilemma. Geological Society London Spec. Publ. 448201610.1144/SP448.10GeyerG.UchmanA.Ichnofossil assemblages from the Nama Group (Neoproterozoic–Lower Cambrian) in Namibia and the Proterozoic–Cambrian boundary problem revisitedBeringeria21995175–202GhienneJ.F.MonodO.KozluH.DeanW.T.Cambrian-Ordovician depositional sequences in the Middle East: a perspective from TurkeyEarth Sci. Rev.1012010101–146GibertJ.M.RamosE.MarzoM.Trace fossils and depositional environments in the Hawaz Formation, Middle Ordovician, western LibyaJ. Afr. Earth Sci.60201128–37HagadornJ.BottjerD.J.Restriction of a Late Neoproterozoic biotope: suspect-microbial structures and trace fossils at the Vendian–Cambrian transitionPalaios14199973–85JensenS.Trace fossils from the Lower Cambrian Mickwitzia Sandstone, south-central SwedenFossils Strata4219971–111JensenS.GrantS.W.F.Trace fossils from the Dividalen Group, northern Sweden: implications for Early Cambrian biostratigraphy of BalticaNorsk Geologisk Tidsskrift781998305–317JensenS.DroserM.L.GehlingJ.G.Trace fossil preservation and the early evolution of animalsPalaeogeogr. Palaeoclimatol. Palaeoecol.220200519–29KellogH.E.The geology of the Derik–Madin area, SE Turkey. Report, Exploration Division American Overseas Petroleum Ltd., 126, 1-34. Ankara (unpublished)1960KnaustD.Cambro-Ordovician trace fossils from the SW-Norwegian CaledonidesGeol. J.3920041–24KnaustD.Invertebrate trace fossils and ichnodiversity in shallow-marine carbonates of the German Middle Triassic (Muschelkalk)BromleyR.G.BuatoisL.A.MánganoG.GeniseJ.F.MelchorR.N.Sediment-organism interactions: a multifaceted ichnology. SEPM Spec. Publ., 882007221–238KnaustD.Siphonichinidae (new ichnofamily) attributed to the burrowing activity of bivalves: ichnotaxonomy, behavior and palaeoenvironmental implicationsEarth Sci. Rev.1502015497–519KnaustD.Atlas of trace fossils in well core. Appearance, taxonomy and interpretation. Springer2017(193 p.)LamsdellJ.C.HoşgörI.SeldenP.A.A new Ordovician Eurypterid (Arthropoda: Chelicerata) from Southeast Turkey: evidence for a cryptic Ordovician record of EurypteridaGondwana Res.232013354–366LesquereuxL.Species of fossil marine plants from the Carboniferous measuresIndiana Geol. Surv. Annu. Rep.71876134–145MacNaughtonR.B.NarbonneG.M.Evolution and ecology of Neoproterozoic-Lower Cambrian Trace Fossils, NW CanadaPalaios14199997–115MánganoM.G.BuatoisL.A.Reconstructing Early Phanerozoic intertidal ecosystems: ichnology of the Cambrian Campanario Formation in Northwest ArgentinaFossils Strata51200417–38MánganoM.G.BuatoisL.A.Decoupling of body-plan diversification and ecological structuring during the Ediacaran-Cambrian transition: evolutionary and geobiological feedbacksProc. Biol. Sci.2812014(20140038)MánganoM.G.BuatoisL.A.GuineaM.Ichnology of the Alfarcito Member (Santa Rosita Formation) of northwestern Argentina: animal-substrate interactions in a Lower Paleozoic wave-dominated shallow seaAmeghiana422005641–668MánganoM.G.BuatoisL.A.HofmannR.ElickiO.ShinaqR.Exploring the aftermath of the Cambrian explosion: the evolutionary significance of marginal- to shallow-marine ichnofaunas of JordanPalaeogeogr. Palaeoclimatol. Palaeoecol.37420131–15MataS.A.CorsettiC.L.CorsettiF.A.AwramikS.M.BotjerD.J.Lower Cambrian anemone burrows from the Upper Member of the Wood Canyon Formation, Death Valley Region, United States: paleoecological and paleoenvironmental significancePalaios272012594–606McIloryD.LoganG.A.The impact of bioturbation on infaunal ecology and evolution during the Proterozoic-Cambrian transitionPalaios14199958–72McIlroyD.BraiserM.D.Ichnological evidence for the Cambrian explosion in the Ediacaran to Cambrian succession of Tanafjord, Finnmark, northern NorwayBrasierA.T.McIlroyD.McLoughlinN.Earth system evolution, early life: a celebration of the work of Martin Brasier2016Geological Society, Spec. Publ. 448London10.1144/SP448.7Mergl HoşgörM.Yılmazİ.Zamoraİ.Ö.ColmenarS.J.Divaricate pattern in the Cambro-Ordovician obolid brachiopods from GondwanaHist. Biol.201810.1080/08912963.2017.1327531(in press)MikulášR.New information on trace fossils of the Early Ordovician of Prague Basin (Barrandian area, Czech Republic)J. Czech Geol. Soc.381993171–182MikulášR.Trace fossils from the Paseky Shale (Early Cambrian Czech Republic)J. Czech Geol. Soc.40199537–54MikulášR.Trace fossils from the Middle Cambrian of the Barrandian area (Central Bohemia, Czech Republic)Czech Geol. Surv. Spec. Pap.122000(29 p.)OrłowskiS.Trace fossils in the Lower Cambrian sequence in the Świętokrzyskie Mountains, central PolandActa Geol. Pol.341989211–231OrłowskiS.RadwnańskiA.Middle Devonian sea-anemone burrows, Alpertia santacrucensis ichnogen.et ichnosp.n., from the Holy Cross MountainsActa Geol. Pol.361986233–248OrlowskiS.ŹylińskaA.Non-arthropod burrows from the Middle and Late Cambrian of the Holy Cross Mountains, PolandActa Palaeontol. Pol.411996385–409PacześnaJ.Ichnological record of the activity of Anthozoa in the Early Cambrian succession of the Upper Silesian Block (southern Poland)Acta Geol. Pol.60201093–103PalijV.M.Remains of non-skeletal fauna and trace fossils from Upper Precambrian and Lower Cambrian deposits of PodoliaRyabenkoV.A.Paleontology and Stratigraphy of the Upper Precambrian and Lower Paleozoic of the south-western Part of the East European Platform1976Naukova DumkaKiev63–77PandeyD.K.UchmanA.KumarV.ShekhawatR.S.Cambrian trace fossils of the Cruziana ichnofacies from the Bikaner-Nagaur Basin, north western Indian CratonJ. Asian Earth Sci.812014129–141ParchaS.K.PandeyS.Ichnofossils and their significance in the Cambrian successions of the Parahio Valley in the Spiti Basin, Tethys Himalaya, IndiaJ. Asian Earth Sci.4220111097–1116PembertonS.G.MagwoodJ.P.A.A unique occurrence of Bergaureria in the Lower Cambrian Gog Group near Lake Louise, AlbertaJ. Paleontol.641990436–440PembertonS.G.FreyR.W.BromleyR.G.The ichnotaxonomy of Conostichus and other plug-shaped ichnofossilsCan. J. Earth Sci.251988886–892PengS.BabcockL.E.CooperR.A.The Cambrian PeriodGradsteinF.M.OggJ.G.SchmitzM.D.OggG.M.The Geologic Time Scale 2012, Volume 2. Elsevier2012437–488PrantlF.Two new problematic trails from the Ordovician of BohemiaAcadémie tchèque des sciences, Bulletin International, Classe des sciences mathématiques, naturelles et de la médecine46194549–59PickerillR.K.Compaginatichnus: a new ichnogenus from Ordovician flysch of eastern CanadaJ. Paleontol.631989913–919PickerillR.K.Bergaueria perata Prantl, 1945 from the Silurian of Cape George, Nova ScotiaAtlantic Geol.251989191–197RadwańskiA.RoniewiczP.Upper Cambrian trilobite ichnocoenosis from Wielka Wiśniówka (Holy Corss Mountains, Poland)Acta Palaeontol. Pol.81963260–278SeilacherA.Spuren und Fazies im UnterkambriumSchindewolfO.H.SeilacherA.Beitrage zur Kenntnis des Kambriums in der Salt Range (Pakistan). Akad. Wiss Lit.1955Naturwiss. Kl. 10Mainz. Abhandl. Math117–143SeilacherA.Trace fossil analysis. Springer2007(226 p.)SinghB.P.BhargavaO.N.ChaubeyR.S.KishoreN.Ichnology and depositional environment of the Cambrian Nagaur Sandstone (Nagaur Group) along the Dulmera section, Bikaner-Nagaur Basin, RajasthanActa Geol. Sin.8820141665–1680StachaczM.Ichnology of the Cambrian Ociesęki Sandstone Formation (Holy Cross Mountains, Poland)Ann. Soc. Geol. Pol.862016291–328SudanC.S.SharmaU.K.Trace fossils from the Cambrian Rocks of the Kunzum La Section, Spiti, H.P, IndiaJ. Paleontol. Soc. India462001161–171VintanedJ.A.G.LinanE.MayoralE.DiesM.E.GozaloR.MunizF.Trace and soft body fossils from the Pedroche Formation (Ovetian, Lower Cambrian of the Sierra de Cordoba, S Spain) and their relation to the Pedroche eventGeobios392006443–468WeberB.SteinerM.ZhuM.Y.Precambrian-Cambrian trace fossils from the Yangtze Platform (South China) and the early evolution of bilaterian lifestylesPalaeogeogr. Palaeoclimatol. Palaeoecol.2542007328–349WeberB.SteinerM.EvseevS.YergalievG.First report of a Meishucun-type Early Cambrian (Stage 2) ichnofauna from the Malyi Karatau area (SE Kazakhstan): palaeoichnological, palaeoecological and palaeogeographical implicationsPalaeogeogr. Palaeoclimatol. Palaeoecol.3922013209–231
A. Map of South-East Turkey showing the position of the Derik–Madin area with location of Cambrian-Ordovician non-metamorphic rocks (Lamsdell et al., 2013). B. Synthetic sketch of the lithologies and stratigraphy of the Cambrian and Early Ordovician formations in the south-eastern Turkey with schematic log showing the Cambrian formations of the Derik area (Dean et al., 1997, Ghienne et al., 2010 and Lamsdell et al., 2013).
A. Carte du Sud-Est de la Turquie, montrant la position de la zone de Derik–Mardin avec la localisation des roches cambro-ordoviciennes non métamorphiques (Lamsdell et al., 2013). B. Schéma synthétique des lithologies et de la stratigraphie du Cambrien et de l’Ordovicien inférieur du Sud-Est de la Turquie, avec un log schématique montrant les formations cambriennes de la zone de Derik (Dean et al., 1997, Ghienne et al., 2010 and Lamsdell et al., 2013).
A–B. Bergaueria perata from the early Cambrian of Zabuk Formation and a mono-ichnospecific entity of the surface positive hyporeliefs Bergaueria. C–D. Plan-view photographs of specimens from the study site, illustrating typical morphological characteristics, including: radial sand-infilled cracks. E–I. Apical view of samples, scale = 5 mm.
A–B. Bergaueria perata du Cambrien inférieur de la formation Zabuk et entité mono-ichnospécifique des hyporeliefs positifs de surface de Bergaueria. C–D. Photographies en vue plane de spécimens du site de l’étude, illustrant les caractéristiques morphologiques typiques, incluant des craquelures radiales remplies de sable. E–I. Vue apicale des échantillons, barre d’échelle = 5 mm.
A. Schematic illustration of shifts in dominant factors influencing the marine siliciclastic sedimentary record during the Ediacaran to Ordovician (Hagadorn and Bottjer, 1999). B. Reconstruction of anemone like animals recorded as plug-shaped burrows on upper bedding surfaces and possible scenarios for trace fossil preservation with particular emphasis on preservation of shallow tiers in a sandy sea floor (Chamberlain, 1971 and Orłowski and Radwnański, 1986). Sea anemones produce Bergaueria-like traces in modern sediments (modified from Knaust, 2017 and Seilacher, 2007). C. Stratigraphic range of Bergaueria and latitudinal distribution of Bergaueria ichnospecies on the Proto-Tethys Ocean during the Early Palaeozoic (Alpert, 1973, Orłowski, 1989, Palij, 1976, Prantl, 1945, Pickerill, 1989a, Pickerill, 1989b and Radwański and Roniewicz, 1963Bayet-Goll and Carvalho, 2017, Buatois et al., 2017, Gibert et al., 2011, Jensen and Grant, 1998, Knaust, 2004, Knaust, 2017, Mángano and Buatois, 2004, Mángano et al., 2005, Mángano et al., 2013, McIlroy and Braiser, 2016, Mikuláš, 1993, Mikuláš, 1995, Mikuláš, 2000, Orlowski and Źylińska, 1996, Pacześna, 2010, Pemberton and Magwood, 1990, Seilacher, 2007, Singh et al., 2014, Stachacz, 2016, Sudan and Sharma, 2001, Vintaned et al., 2006 and Weber et al., 2007).
A. Illustration schématique des changements de facteurs dominants influençant le registre sédimentaire siliciclastique marin de l’Ediacarien à l’Ordovicien (Hagadorn et Bottjer, 1999). B. Reconstitution des animaux de type anémone répertoriés sous forme de cavités à bouchon sur la partie superficielle des lits et scénarios possibles pour la préservation des traces de fossiles, l’accent étant mis sur la préservation de rangées étroites sur le plancher marin sableux (Chamberlain, 1971 and Orłowski and Radwnański, 1986). Les anémones marines produisent des traces de type Bergaueria dans les sédiments modernes (modifié d’après Knaust, 2017 and Seilacher, 2007). C. Étendue stratigraphique de Bergaueria et distribution latitudinale de l’ichnoespèce dans l’océan Proto-Téthysien pendant le Paléozoïque inférieur.