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Eksploracja głębin Morza Karaibskiego w rejonie wyspy Roatán (Honduras) przez polskich paleontologów : teraźniejszość kluczem do poznania przeszłości

Gorzelak Przemysław, Salamon Mariusz A.

Przegląd Geologiczny

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2023

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Vol. 71, nr 2

71--81

EN

The island margin of Isla de Roatán is a unique place of outstanding scientific and didactic values, with one of the longestcoral reef and an astonishing fauna inhabiting the deep sea zones. The unique geomorphological conditions enable to perform shore-based submersible operations at great depths. In this paper a short report from our dive down to about 650 m is presented. Our preliminary dive was used to document a diverse faunal assemblage, which allowed for a better understanding of the fossil record.

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A new Danian echinoid assemblage from the Greensand in the Kazimierz Dolny area, central Poland: taxonomy, taphonomy and sedimentological implications

Machalski M., Jagt J. W. M.

Acta Geologica Polonica

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2018

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Vol. 68, no. 4

571--596

EN

We describe a new echinoid assemblage, composed of specimens of Bolbaster sp., Cyclaster danicus (Schlüter, 1897), Diplodetus vistulensis (Kongiel, 1950) and Linthia? sp. in a distinctive phosphatic preservation, from the so-called Greensand, a marly glauconitic sandstone horizon at the base of the Danian succession in the Kazimierz Dolny area (central Poland). This assemblage presumably is of early Danian age, with Cyclaster danicus occurring in the lower Danian of Denmark and southern Sweden. The specimens are preserved as internal moulds, composed of phosphatised glauconitic sandstone, occasionally with some test material adhering. The genesis of these moulds involved the following steps: (1) infilling of tests of dead echinoids with glauconitic sand; (2) penetration of the infills by coelobiotic deposit-feeding organisms that produced burrows along the inner test surface; (3) early-diagenetic cementation of infills by calcium phosphate; and (4) exhumation and intraformational reworking of specimens, leading to abrasion, fragmentation and loss of test material in some individuals. Co-occurring are unphosphatised moulds of Echinocorys ex gr. depressa (von Eichwald, 1866) and Pseudogibbaster cf. depressus (Kongiel in Kongiel and Matwiejewówna, 1937), which may represent a younger (middle to late Danian) assemblage. Additionally, the presence of derived late Maastrichtian echinoids, e.g., Temnocidaris (Stereocidaris) ex gr. herthae (Schlüter, 1892), Pleurosalenia bonissenti (Cotteau, 1866) and Hemicara pomeranum Schlüter, 1902, is confirmed for the Greensand, based on new material and re- examination of previously recorded specimens. In summary, members of three echinoid assemblages of different age and preservation occur together in the Greensand. Our results are compatible with former interpretations of this unit as a condensed, transgressive lag with mixed faunas of different age and provenance. However, they are incompatible with the hypothesis that phosphatised Danian fossils preserved in the Greensand are derived from a facies equivalent, now gone, of the lower Danian Cerithium Limestone in eastern Denmark, because all moulds are composed of phosphatised glauconitic sandstone that is utterly different from the calcareous dinocyst-dominated, fine crystalline matrix of the Cerithium Limestone.

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Palaeoenvironmental interpretation of echinoderm assemblages from Bathonian ore-bearing clays at Gnaszyn (Kraków-Silesia Homocline, Poland)

Boczarowski A.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

351-366

EN

This paper presents the results of an investigation into the variability of echinoderm assemblages from Bathonian ore-bearing clays from Gnaszyn. Remains of Crinoidea, Asteroidea, Ophiuroidea, Echinoidea, and Holothuroidea have been studied from 38 rock samples. The most common echinoderms represented are the crinoids Balanocrinus berchteni and Chariocrinus andreae and a few species of the holothurian genera Priscopedatus, Calclamna, Staurocaudina, Eocaudina, Achistrum, Theelia and Hemisphaeranthos. The echinoderms from Gnaszyn show various life strategies: benthic or epibenthic forms, sessile sestonophages (Crinoidea), motile macrophages (Asteroidea) and detritivores (Asteroidea, Ophiuroidea, Echinoidea), infaunal and epifaunal detritus feeders, sediment feeders or rake-feeders (Holothuroidea). Their presence suggests well oxygenated and presumably relatively cold bottom marine waters. The parts of the Gnaszyn section around concretion horizons and characterized by the ubiquitous occurrence of the holothurian Theelia and echinoids were deposited during phases of optimal living conditions with sufficient influx of plant detritus and good oxygenation of the sea bottom. These parts commonly host echinoderm associations dominated by crinoid remains, which occasionally are still articulated (or disarticulated but remaining intact) - this points to a quiet environment with normal oxygenation of the bottom waters but anaerobic/dysaerobic conditions in the sediment.

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A goniasterid starfish (Echinodermata, Asteroidea) preserved in a mid-Miocene rhyolitic ignimbrite, northwest Romania

Jagt J., Codrea V.

Acta Geologica Polonica

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2010

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Vol. 60, no. 2

275-282

EN

A well-preserved, near-complete goniasterid asteroid, provisionally referred to the genus Ceramaster, is recorded from a rhyolitic ignimbrite assigned to the Dej Tuff Formation, exposed near Ciceu Giurgesti (northwest Romania). The main interest of this specimen lies in the fact that it constitutes a rare example of preservation of (shallow-) marine biota, and echinoderms in particular, in volcanic strata. Superficially, overall disc shape and size, as well as ornament of marginal and abactinal ossicles, resemble to some extent that of coeval and slightly younger material from the Paratethys (south-central Poland, Austria) and the North Sea Basin (northwest Belgium), previously assigned to Ceramaster. So far, only the Polish and Austrian material has been formally named; however, this might actually represent but a single species. The record from Belgium refers to a form which is either conspecific with C. muelleri from the Paratethys, or represents a closely related taxon. These, and associated asteroids (e.g., Astropectinidae, Luidiidae), are in need of a modern taxonomic revision and a reappraisal of their palaeoecology is called for as well.

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Systemy piętrowych nor krewetek-alfeuszy i ich znaczenie środowiskowe w oksfordzie i kimerydzie Gór Świętokrzyskich

Radwańska U., Radwański A.

Volumina Jurassica

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2004

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Vol. 2, no. 1

113-130

EN

To the activity of alpheid shrimps genus Alpheus Weber, 1795) ascribed are the tiered burrows of a gridlike appearance from Lower Kimmeridgian oolitic shoals and Middle Oxfordian nearshore micritic limestones of the Holy Cross Mountains, Central Poland. The burrow networks are confined to beds of the soft or hard bottom type, the upper parts of which are more or less deeply truncated, to indicate erosional events of storm agitation. At low stand, the open burrows served as traps for solutions derived from the nearby hypersaline lagoons of the sabkha type, to cause precipitation either of dolomite, or of silica gel. At high stand, the open burrows, exemplified by the Małogoszcz section (Lower Kimmeridgian), became taphonomic traps and/or crevice habitats for diverse biota, the echinoderms in particular, to form their graveyards (EchinodermenlagerstŹtten). In these, represented are echinoids (tests, some spine-coated, all either empty, or sediment-filled; broken tests and their fragments, spines) stalkless crinoids (cusps, centrodorsals, radials, brachials, cirrals), stalked crinoids (columnals, pluricolumnals), starfish (marginalia, ambulacral plates), and ophiuroids (vertebrae, arm plates). Eco-taphonomic pathways for particular echinoderms (21 taxa taxonomically recognised) are interpreted since their death to burial in open burrows. Spine-coated echinoids were entrapped alive, others were swept into during successive storms which acted as a lethal agent. The storms, catastrophic for echinoderm communities, have prevailed through a longer timespan, when the alpheid-burrowed shoal evolved from the soft bottom to the hard ground colonized by a successive echinoderm community dominated by stalked crinoids.

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Rekonstrukcja paleośrodowiska sedymentacji środkowojurajskich iłów rudonośnych Gnaszyna (Częstochowa) - wyniki wstępne

Gedl P., Kaim A., Boczarowski A., Kędzierski M., Smoleń J., Szczepanik P., Witkowska M., Ziaja J.

Volumina Jurassica

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2003

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Vol. 1, no. 1

19-28

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Krawędzie bioherm mikrobialitowo-gąbkowych miejscem znacznego nagromadzenia płytek szkarłupni

Ostrowski S.

Volumina Jurassica

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2003

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Vol. 1, no. 1

59-62