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Naturtejo : pierwszy portugalski geopark

Pijet-Migoń Edyta, Migoń Piotr

Przegląd Geologiczny

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2019

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Vol. 67, nr 1

41--47

EN

Naturtejo Geopark is the oldest among the UNESCO Global Geoparks in Portugal, which was admitted to the then Global Geopark Network in 2006. It is located in the eastern part of the country, on both sides of the Tagus River, close to the border with Spain. The highlights of regional geoheritage include spectacular granite landforms (inselbergs, tors, pedestal rocks), excellent exposures of Ordovician ichnofossils, deeply incised river reaches that expose deformed Lower Paleozoic basement rocks and remnants of past mining activities. The area has also rich cultural heritage which goes back to Roman times. Sixteen designated geosites and numerous walking trails are the main attractions for tourists, but the Geopark is also engaged in developing various innovative tourist and educational products focused on both geo- and cultural heritage, as well as linkages between the two.

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New ichnotaxa of vertebrate burrows from the Salt Wash Member, Upper Jurassic Morrison Formation, south-eastern Utah (USA)

Raisanen D. C. W., Hasiotis S. T.

Annales Societatis Geologorum Poloniae

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2018

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Vol. 88, No. 2

181--202

EN

Large-diameter burrows in pedogenically modified floodplain deposits in the Salt Wash Member, Upper Jurassic Morrison Formation, southeast Utah, U.S.A., are interpreted to have been constructed by mammals. They are distinguished as Daimonelix martini isp. nov., which exhibits a helical shaft down to a horizontal tunnel with a mean depth of 71.4 cm from the inferred palaeosurface. The mean path length of the shaft is 99.4 cm; mean dip of the whorls is 39°. The mean tunnel length is 42.3 cm. Shafts and tunnels are oval or elliptical in cross section with the horizontal diameter slightly larger than the vertical (ratio of -1.26:1); the shaft averages 9.2 cm wide and 7.3 cm tall; the tunnel averages 10.7 cm wide and 10.7 cm tall. The tracemaker was likely a fossorial mammal that used the burrow as a den to shelter when not foraging above ground; the burrows are domichnia. The other from the same member is Fractisemita henrii igen. nov. et isp. nov., a network of interconnected shafts and tunnels; shaft and tunnel segments are straight, curved, or helical. The segments are at angles of 0-89°; mean length of a section is 30.7 cm. The cross sections of all elements are oval or elliptical; the mean width is 6.3 cm and the mean height is 4.9 cm (ratio of -1.29:1). The burrows are interpreted as the work of a social mammal and represent multiple tracemaker behaviours: protection, denning, foraging, and possibly food storage. The burrows are polychresichnia. Surficial morphologic features preserved on the burrow walls of both types are interpreted as scratches made by the tracemaker claws and/or teeth. The burrows reveal the actions of small vertebrates not recorded by body fossils showing potential partitioning of the environment and availability of resources for small vertebrates.

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Early Cambrian trace fossils at the northern margin of the Arabian Plate; Telbesmi Formation, Turkey

Demírcan H., Gürsu S., Göncüoğlu M. C.

Acta Geologica Polonica

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2018

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Vol. 68, no. 2

135--145

EN

The Telbesmi Formation, at the northern margin of the Arabian Plate, Turkey, is composed of alternating darkbrown, pinky-brown fluvial arkosic sandstone/mudstones with thin-bedded cherty limestones and channel conglomerates. The formation contains rare and poorly diversified trace fossils. The siltstone/sandstone beds of levels 1 and 2 of the formation yielded, however, a moderately diverse assemblage composed of: Cochlichnus isp., Palaeophycus isp., Planolites beverleyensis, Teichichnus isp. and ?Treptichnus rectangularis. This assemblage, made up of traces left by deposit feeding organisms, represents the Scoyenia ichnofacies. Treptichnus rectangularis and Palaeophycus isp., of the assemblage, can be considered markers for the base of the Cambrian in southeast Turkey.

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The trace fossil Lepidenteron lewesiensis (Mantell, 1822) from the Upper Cretaceous of southern Poland

Jurkowska A., Uchman A.

Acta Geologica Polonica

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2013

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Vol. 63, no. 4

611--623

EN

Lepidenteron lewesiensis (Mantell, 1822) is an unbranched trace fossil lined with small fish scales and bones, without a constructed wall. It is characteristic of the Upper Cretaceous epicontinental, mostly marly sediments in Europe. In the Miechów Segment of the Szczecin-Miechów Synclinorium in southern Poland, it occurs in the Upper Campanian–Lower Maastrichtian deeper shelf sediments, which were deposited below wave base and are characterized by total bioturbation and a trace fossil assemblage comprising Planolites, Palaeophycus, Thalassinoides, Trichichnus, Phycosiphon, Zoophycos and Helicodromites that is typical of the transition from the distal Cruziana to the Zoophycos ichnofacies. L. lewesiensis was produced by a burrowing predator or scavenger of fishes. The tracemaker candidates could be eunicid polychaetes or anguillid fishes.

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Arachnostega Bertling, 1992 in the Drumian (Cambrian) sediments of the Tepla-Barrandian region (Czech Republic)

Fatka O., Mikulas R., Szabad M., Micka V., Valent M.

Acta Geologica Polonica

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2011

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Vol. 61, no. 4

367-381

EN

The presence of the ichnospecies Arachnostega gastrochaenae Bertling, 1992 is documented from the Cambrian for the first time. It occurs in several stratigraphical levels of the "middle" Cambrian sediments in the Pribram-Jince and Skryje-Tyrovice basins of the Tepla-Barrandian region in the Czech Republic. Simple tunnels as well as the complicated morphologies of Arachnostega were observed on internal moulds of trilobite exoskeletons and hyolith conchs and represent the oldest record of this ichnogenus. The Cambrian occurrences of Arachnostega on skeletal body fossils evoke the connection between the Arachnostega-type feeding strategy and the sudden appearance of numerous skeletal animals. The development of the Arachnostega-type behaviour can be considered a feature of the "Cambrian substrate revolution".

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Coniacian-?Santonian paralic sedimentation in the Rakowice Małe area of the North Sudetic Basin, SW Poland: sedimentary facies, ichnological record and palaeogeographical reconstruction of an evolving marine embayment

Leszczyński S.

Annales Societatis Geologorum Poloniae

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2010

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Vol. 80, No 1

1-24

EN

The Coniacian-?Santonian siliciclastic succession outcropped in a sandstone quarry at Rakowice Małe (Żerkowice Member of the Rakowice Wielkie Formation, and the Czerna Formation including the Nowogrodziec Member; North Sudetic Basin, SW Poland) provides an interesting example of paralic deposits. Lithofacies and ichnofossil examination indicate coastal, lacustrine, paludal and lagoonal sedimentation. Valuable new data are supplied by trace fossils, a feature not considered yet in the literature on the Upper Cretaceous of the North Sudetic Basin. Trace fossils are overall abundant in the upper part of the Nowogrodziec Member and overlying part of the Czerna Formation. The following ichnogenera: Thalassinoides, Ophiomorpha, Asterosoma, Palaeophycus, Planolites, Skolithos, Teredolites, Chondrites, Cylindrichnus, Arenicolites, Rosselia, Teichichnus, Phycodes, Phycosiphon, and Schaubcylindrichnus are represented. The trace fossils represent the Skolithos, Teredolites and Cruziana ichnofacies. The Cruziana Ichnofacies is typified by the richest trace fossil assemblage characteristic of its archetypal, proximal and stressed expressions. An upper shoreface to foreshore origin of these sediments is documented using lithofacies and the ichnofossils Ophiomorpha and Thalassinoides in the exposed part of the Żerkowice Member. Dominance of kaolinite, lack of burrows and upward passage into paludal deposits is interpreted to indicate a lacustrine origin of variegated clayey mudstone at the base of the Nowogrodziec Member. The changes of depositional environments are interpreted as resulting from separation of the area from the open sea by a sand barrier formed due to the termination of the forced regression. Siltstones containing plant roots and fragments of drifted wood showing the trace fossil Teredolites clavatus, together with coal-seams containing Thalassinoides isp., are assigned to indicate a coastal plain, paludal deposition of the overlying part of the Nowogrodziec Member and incursion of marine waters. The fining upward sequence constituting the top part of the Nowogrodziec Member and showing almost archetypal Cruziana Ichnofacies substituted by its expression indicative of highly stressed, brackish conditions are shown to indicate extensive drowning of the area and lagoonal sedimentation. Termination of the drowning, embodied in a maximum flooding surface, is indicated in a bed of coaly mudstone at the top of the Nowogrodziec Member. Sedimentation on a periodically prograded brackish bay shoreface is inferred from lithofacies, ichnofossils and body fossils for the deposits overlying the Nowogrodziec Member and topping the examined succession. The trace fossils indicate Cruziana Ichnofacies and Skolithos Ichnofacies in the expression of slightly stressed environ- ments. The whole examined part of the Czerna Formation is interpreted as a fifth-order transgressive-regressive cycle.

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Sedimentary facies, ichnofossils and storm deposits in the Lower Permian Taiyuan Formation, Jiaozuo city, Henan Province, central China

Hu B., Song H., Liu S., Zhang L.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

45-52

EN

Five sedimentary facies - neritic carbonate platform, lagoon, tidal flat, swamp and barrier island facies - are recorded in the Lower Permian Taiyuan Formation along with abundant ichnofossils. Common ichnofossils in this formation include Zoophycos villae, Zoophycos brianteus, Nereites cf. missouriensis, Chondrites isp., Gordia marina, Taenidium isp., Thalassinoides isp., Palaeophycus isp., Planolites isp. and a kind of bifurcation trail. From observations of the morphology of Zoophycos spreiten in approximately vertical sections, at least three kinds of spreite laminae are distinguished: ligular, crescentic and rectangular forms. Four types of storm deposits (coded as A, B, C, D) are recognised in the carbonates of the Taiyuan Formation and can be explained forming in shallow marine environments, which are distributed in order from near storm wave base to near fair weather wave base respectively.

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Ptychoplasma conica isp. nov. - a new bivalve locomotion trace fossil from the Lower Jurassic (Hettangian) alluvial sediments of Sołtyków, Holy Cross Mountains, Poland

Pienkowski G., Uchman A.

Geological Quarterly

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2009

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Vol. 53, No 4

397-406

EN

A new locomotion (repichnion) trace fossil, Ptychoplasma conica isp. nov., which is composed of chains of hypichnial mounds, is described from Hettangian alluvial sediments in Central Poland. Its occurrence is limited to amalgamated crevasse sand stones. The trace fossil is associated with freshwater bivalves belonging probably to Unionidae. This trace fossil reflects rhythmic (?diurnal) movement of the tracemaker in accordance with the direction of flow in the crevasse channel, where the forward movement took place in the shallow part of a sandstone layer and was interrupted by resting episodes in deeper sediment layer along the mud-sand inter ace. Episodic flood events forced bivalves to produce escape structures, moving from deeper (previous) to upper (later) levels of lateral movements. Some vertical burrows with bivalve body fossils preserved at the bottom suggest a taphonomic burial. P. conica ranges from Late Triassic to Hettangian.