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Palaeoecologic significance of the Callovian-Oxfordian trace fossils of Gangeshwar Dome, Southeast of Bhuj, Mainland Kachchh, India

Bhatt N. Y., Patel S. J.

Volumina Jurassica

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2017

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Vol. 15, no 1

17--40

EN

The shallow marine deposits of the Late-Middle Jurassic (Callovian–Oxfordian) Jumara Formation of the Gangeshwar Dome of Mainland Kachchh, India, comprise a succession of ~247 m thick clastic sediments with few non-clastic bands and contain a diverse group of ichnofauna. The succession is subdivided into seven lithofacies, viz., laminated shale-siltstone facies (LSS), sheet sandstone facies (SS), herringbone sandstone facies (HS), bivalve sandstone facies (BS), bioclastic limestone facies (BL), intraformational conglomerate facies (IC) and oolitic limestone facies (OL). The ichnofaunal study shows 29 ichnospecies of 23 ichnogenera including Arenicolites, Bifungites, Bolonia, Chondrites, Didymaulichnus, Diplocraterion, Gyrochorte, Helminthopsis, Isopodichnus, Laevicyclus, Lockeia, Monocraterion, Taenidium, Ophiomorpha, Palaeophycus, Planolites, Phycodes, Protopalaeodictyon, Rhizocorallium, Skolithos, Thalassinoides, Tisoa, and Zoophycos. These trace fossils are distributed among nine ichnocoenose, characterized by Chondrites, Diplocraterion, Gyrochorte, Ophiomorpha, Rhizocorallium, Skolithos, Taenidium, Thalassinoides and Zoophycos. Their occurrence in the facies corresponds to their trophic and ethological properties. The colonisation of the opportunistic Diplocraterion and the Skolithos ichnocoenose shows a high den¬sity and marks foreshore/nearshore environmental conditions. The Gyrochorte, the Rhizocorallium, the Taenidium and the Thalassinoides ichnocoenose indicate the typically lower energy zone of the shoreface-offshore region. The Chondrites ichnocoenosis indicates fluctuation in bottom water oxygen while the Zoophycos ichnocoenosis typically exploited a calm water niche in the offshore region. These ich-nocoenose recur throughout the sequence and belong to the Skolithos and the Cruziana ichnofacies which marked changes in energy gradient, substrate stability, water depth and mode of life of invertebrate organisms. The study of trace fossil assemblages with sediment characteristics gives a detailed and accurate picture of foreshore to offshore palaeoenvironmental conditions.

2

Eocene flora and trace fossils from the Hruby Regiel section in the Tatra Mountains (Poland): Taxonomic revision of the Wiktor Kuźniar fossil plant collection

Worobiec G., Jach R., Machaniec E., Uchman A., Worobiec E.

Acta Geologica Polonica

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2015

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Vol. 65, no. 2

203--226

EN

Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.

3

Trace fossils from the Lower Muschelkalk of Raciborowice Gorne (North Sudetic Synclinorium, SW Poland) and their palaeoenvironmental interpretation

Chrząstek A.

Acta Geologica Polonica

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2013

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Vol. 63, no. 3

315--353

EN

The following trace fossils have been recognised in the Lower Muschelkalk of Raciborowice Gorne (North Sudetic Synclinorium, SW Poland): Archaeonassa fossulata, Balanoglossites triadicus, ?Gastrochaenolites isp., Lockeia isp., Palaeophycus tubularis, Palaeophycus isp., ?Planolites beverleyensis, P. montanus, Planolites isp., ?Protovirgularia isp., Rhizocorallium commune var. auriforme, R. commune var. irregulare, R. jenense, Skolithos linearis, Thalassinoides suevicus and Trypanites weisei. Coprolites and an unidentified trace fossil A are also described. The trace fossils allow the discrimination of five ichnoassociations in the Raciborowice G1) Rhizocorallium- Pholeus, (IA 2) Rhizocorallium-Palaeophycus, (IA 3) Thalassinoides, (IA 4) Trypanites-Balanoglossites and (IA 5) Planolites-Palaeophycus. The Lower Muschelkalk succession was deposited on a shallow carbonate ramp affected by frequent storms. Deposition commenced with sedimentation in a restricted lagoon on the inner ramp with a short episode of sabkha formation. It continued on the middle and outer ramp and then on a skeletal shoal of the outer ramp and in an open basin. Ichnoassociation IA 5 is related to a maximum transgression that commenced with the deposition of the Spiriferina Bed and which probably marked the opening of the Silesian-Moravian Gate. The basin underwent two shallowing episodes, as evidenced by ichnoassociations IA 3-IA 4, resulting in the formation of hardgrounds. Bathymetric changes in the Raciborowice Gorne section correspond well with a general transgressive trend in the Germanic Basin.

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Sedimentary environment and palaeogeography of the ?Palaeocene-Middle Eocene Kashkan Formation, Zagros fold-thrust belt, SW Iran

Yeganeh Bizhan Yousefi, Feiznia Sadat, Loon A. J. (Tom)

Geologos

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2012

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Vol. 18, No. 1

13--36

EN

The Kashkan Formation (?Palaeocene to Middle Eocene) in the Zagros fold-thrust belt, SW Iran, which is intercalated between to marine limestone formations, consists of conglomerates, sandstones and siltstones. The sedimentology and the palaeogeography of the Kashkan Formation had not received any attention thus far, but have now been studied in seven sections, situated in the province of Lorestan. The sediments form twelve lithofacies, three ichnosubfacies and seven architectural elements, which are described, depicted and analysed. The analysis leads to the conclusion that most sediments accumulated in a low-sinuosity, low-gradient braided-river system (characterised by mainly unidirectional palaeocurrent directions, and by sheetfloods), that occasionally showed meandering characteristics (represented by overbank deposits and large bars). The deposits of this system closely resemble those of the South Saskatchewan River in Canada, which is considered as the classical example of a sand-bed braided river. The river flowed roughly from North to South, as deduced by palaeocurrent indicators such as imbrication and large- to medium-scale trough cross-stratification (direction measured in the trough axes). This current direction is supported by the southward to south-westward thinning of the formation and by the diminishing average grain size in the same direction. The trace fossils in the Kashban Formation fit all in the Skoyenia ichnofacies, which has here three ichnosubfacies which allow a more detailed palaeoenvironmental reconstruction, indicating that the braided stream passed into the low-energy shoreface zone of a tidally-influenced sea.

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Unusual preservation of Ophiomorpha in middle Miocene rocks of Wadi Zablah, east Matruh area, northwestern Egypt

Gameil M., Sadek S.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

39-44

EN

Unusual biogenic structures in the form of hollow burrows are preserved in middle Miocene sandy limestones (calcarenites) exposed in Wadi Zablah, east of the town of Mersa Matruh along the Egyptian Mediterranean coast. This calcarenite unit is about 30 m thick and lies in the middle part of the Marmarica Formation. The burrows commonly are up to 2.5 m long and can reach a length of 3 m in some outcrops. The internal diameter ranges from 1 to 5 cm. In most cases there is a hard cemented zone surrounding the hollow burrows that ranges in thickness from 0.2 to 0.4 cm. In several burrows where the hard cemented zone is preserved, a knobby sculpture is visible on the internal surfaces of the burrows. This is considered to be a negative mold of the pelleted wall of Ophiomorpha. This inverted knobby sculpture is formed by the cemented zone, which permitted the trace fossils. preservation, the original Ophiomorpha wall having been dissolved away during or subsequent to lithification by subsequent weathering processes. The presence of these burrows in association with marine fossils suggests a littoral to very shallow shelf environment.

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Three-dimensionally integrated trace fossils from shallow-marine deposits in the Lower Cretaceous of the Neuquen Basin (Argentina) : Hillichnus agrioensis isp. nov.

Pazos P., Fernandez D.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

105-118

EN

A complex trace fossil that requires a three-dimensional (3D) reconstruction is described and interpreted. The specimens studied are assigned to a new ichnospecies (Hillichnus agrioensis) of Hillichnus Bromley et al., 2003. Most of them are uncollectable and a compound iconotype was designed to characterise the new ichnospecies. The three-dimensional trace fossil has been recorded in marginal-marine deposits close to the top of the Agrio Formation (Lower Cretaceous of Neuquen Basin, Argentina). The new ichnospecies shows a different pattern of feeding than H. lobosensis Bromley et al., 2003, and records defaecation downward in the deeper preservational level (level 4). Feather-like structures (level 2) that typify the ichnogenus also record the activity of an inhalant siphon and indicate a retractile movement. The vertical shafts (level 1) are scarcely recorded. Aligned double rings also document the infaunal habit of the tellinid bivalves that are considered the most likely producers of the trace. It is clear that when only level 2 is exposed, in some cases this form can be assigned to Jamesonichnites heinbergi Dam 1990a consequently, this ichnospecies is interconnected with more than one ichnogenus. Vertical projections recorded in branches differ from the type ichnospecies H. lobosensis Bromley et al., 2003. The occurrence in marginal-marine facies is congruent with the record of Jamesonichnites but not common in the type species and similar to those more frequent in deep-sea deposits (e.g. Polykampton alpinum Ooster, 1869).

7

The trace fossil Rusophycus versans from the Furongian (Upper Cambrian) of central Poland - an example of behavioural convergence amongst arthropods

Sadlok G., Machalski M.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

119-123

EN

Traces assigned to Rusophycus versans are recorded for the first time from Furongian (Upper Cambrian) strata, as exposed at Wiśniówka Wielka quarry, Holy Cross Mountains, central Poland. These traces are ascribed to the life activity of trilobites in a fully marine environment. In contrast, previous records of R. versans have been attributed to notostracans, isopods or arthropleurids and are preserved in non-marine settings. The relatively wide phylogenetic distribution of R. versans within various arthropod groups indicates that this ichnotaxon represents behavioural convergence amongst arthropods.

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Ichnological record of the activity of Anthozoa in the early Cambrian succession of the Upper Silesian Block (southern Poland)

Pacześna J.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

93-103

EN

A new occurrence of inferred Anthozoa trace fossils from the Lower Cambrian subsurface succession of the Upper Silesian Block is discussed with respect to their ichnotaxonomical variation and some aspects of the palaeoecology. The three ichnogenera Bergaueria Prantl, 1945, Conichnus Mannil, 1966 and Conostichus Lesquereux, 1876 have been identified. A relatively diverse assemblage of actinian or cerianthid trace fossils allows recognition of habitats, feeding modes and life strategies of the tracemakers. An example of probable anthozoanpolychaete mutualism is suggested on the basis of the interrelationships of the trace fossils.

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Ichnocoenoses in the Oligocene to Miocene foredeep basins (Northern Apennines, central Italy) and their relation to turbidite deposition

Monaco P., Checconi A., Milighetti M.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

53-70

EN

Analysis of trace fossil abundance and diversity in the Oligocene to Miocene foredeep and piggyback basins of the Tuscan-Romagna-Umbrian Apennines allows us to recognize five ichnocoenoses. The deposits reflect sedimentary environments from slope to basin plain, whose sedimentation was directly controlled by synsedimentary tectonics: attached fan lobes and channels, lobe- and channel-fringes, overbank-fringes of intrabasinal highs, distal detached lobes of basin plain and slope-proximal interfans. The graphoglyptid: non-graphoglyptid ratio has been considered as the chief factor in the study of ichnologic material from Falterona-Cervarola-Trasimeno, Marnosoarenacea and Marne di Vicchio-Verghereto stratigraphic units. The study shows that there is an increase in ichnodiversity and ichnodensity of graphoglyptids, which are typical mainly in detached lobes of basin plain and overbank-levee deposits whose background ichnofauna also shows better preservation.

10

Trace fossils from the Lower-Middle Jurassic Bardas Blancas Formation, Neuquen Basin, Mendoza Province, Argentina

Bressan G., Palma R.

Acta Geologica Polonica

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2009

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Vol. 59, no. 2

201-220

EN

Trace fossil associations from the Lower.Middle Jurassic siliciclastic succession of the northern Neuquen Basin, Argentina are described and their palaeoenvironmental interpretation is discussed. The Bardas Blancas Formation displays facies of lower foreshore to offshore environments, such as massive and laminated mudstones, laminated siltstones, hummocky cross-stratified sandstones, massive and laminated sandstones, wave-rippled sandstones, as well as fine- to medium-grained bioclastic sandstones and massive conglomerates. They contain a trace fossil assemblage low in abundance but high in diversity. The assemblage, comprising eleven ichnogenera, is dominated by Skolithos, Chondrites, Thalassinoides, Planolites, Palaeophycus, Taenidium, Gyrochorte and Arenicolites. Gordia, ?Diplocraterion and Lockeia are less abundant. These trace fossils belong to the Skolithos, Cruziana and Zoophycos ichnofacies. Their distribution is controlled mainly by hydrodynamic energy, substrate consistency and oxygen levels. Storm beds exhibit two successive stages of colonization: (1) the pioneer stage, during which Skolithos, Diplocraterion and Arenicolites (elements of the Skolithos ichnofacies), were produced; and (2) the stable environment stage, represented by Chondrites, Thalassinoides, Taenidium, Gyrochorte, Gordia, Lockeia, Palaeophycus and Planolites (elements of the Cruziana ichnofacies). deeper environments exhibit a low diversity association with Chondrites and Thalassinoides, characterizing the Zoophycos ichnofacies.

11

Deformacje skamieniałości śladowych a proces kompakcji w wapieniach mikrytowych górnej jury okolic Korzkwi (Wyżyna Krakowska)

Ziółkowski P.

Volumina Jurassica

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2005

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Vol. 3, no. 1

55--61

EN

Upper Jurassie (Oxfordian, Bimmammatum Zone) micritic limestones show presence of omission surface of firmground character with trace fossils assemblage. Deformations of burrows are used to quantitative determination of mechanical compaction, applying Ricken's model. Presented results may be used in reconstruction of sea bottom relief during Late Jurassie in area of study.

12

Skamieniałości śladowe w ordowiku strefy Koszalin-Chojnice-nowe dane

Podhalańska T.

Przegląd Geologiczny

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2004

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Vol. 52, nr 12

1166--1170

EN

Amoderately rich trace fossil assemblage in the Ordovician rocks of the Koszalin-Chojnice area (NW Poland) has been recovered for the first time. Previously the only evidence of trace fossils was represented by the clusters of small cylindrical pellets assigned to the Tomaculum problematicum [Groom]. The newly discovered trace fossils occur in greyish-brown and greyish-green claystone and silty claystone of Llanvirnian to Lower Caradocian [teretiusculus - multidens zones]. The most diverse and well-preserved trace fossils have been found in the Skibno 1 profile. They are known also from the other deep boreholes: Jamno IG 2, Miastko 1, Polskie Łąki IG 1 and Chojnice 5. The ichnofossil association is represented mainly by fodinichnia of the deposit feeders: Planolites isp. and Chondrites isp. In the multidens zone of the Skibno 1 profile, domichnia of suspension feeders: ? Cylindrichnus isp., ? Bergaueria isp. and Palaeophycus isp. appear. Ordovician ichnofossils from deep boreholes of the Koszalin-Chojnice area differfrom the Nereites ichnofacies which has been identified on the Rügen Island [Germany]. The intervals with trace fossils define the levels of better oxygenation and the presence of domichnia of suspension feeders in the upper part of the Lower Caradocian-a new feeding resources in a more agitated and probably shallower environment.