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Upper Cambrian trilobite ichnocoenosis from Wielka Wisniowka (Holy Cross Mountains, Poland)

100%

Radwanski A., Roniewicz P.

Acta Palaeontologica Polonica

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1963

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tom 08

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nr 2

Description is given of the Upper Cambrian trilobite ichnocoenosls, i.e. a trace assemblage of the various life activities of trilobites, from the shallow-water marine deposits at Wielka Wiśniówka in the Holy Cross Mountains (Góry Świętokrzyskie). These traces occur either on the upper sides of layers (true traces) or on the lower sides of layers covering grooves made by trilobites on the sea bottom (sole markings = hieroglyphs). Hieroglyphs are the more common forms. Out of them, Rusophycus sp., Cruziana sp., Diplichnites sp. and Dimorphichnus sp. have been described in greater detail. Bergaueria perata Prantl and Diplocraterion sp. hieroglyphs are also encountered in the trilobite ichnocoenosis here reported.

2

Phosphatised olenid trilobites and associated fauna from the Upper Cambrian of Vastergotland, Sweden

100%

Ahlberg P., Szaniawski H., Clarkson E. N. K., Bengtson S.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 3

Secondarily phosphatised olenid trilobites from organic−rich limestones (orsten) in the Furongian (Upper Cambrian) of Västergötland, south−central Sweden, are described and illustrated. All trilobites originate from the Peltura scarabaeoides Zone and were collected on the western slope of Kinnekulle. Only the dorsal exoskeletons have become secondarily phosphatised, and the ventral appendages are not preserved. Yet the material is otherwise remarkably well preserved and reveals the morphology of the olenid trilobites in greater detail than hitherto known. Species belonging to the genera Ctenopyge, Sphaerophthalmus, Parabolina, and Peltura are identified, and several juvenile specimens are present in the material. The material is disarticulated and fragmentary, and it has only been possible to identify a few specimens to species level. In addition to chaetognaths and conodonts, the trilobites are associated with pelmatozoan columnals, a possible camaroid, and fossils of uncertain affinities. These fossils, along with a probable conulariid fragment from the Peltura minor Zone, are also described and discussed. The presence of a benthic fauna of pelmatozoans, and possible conulariids and camaroids, indicates that at least parts of the Peltura zones were deposited during dysoxic rather than anoxic periods. Moreover, the sea floor must have been firm enough to allow colonisation by sessile organisms.

3

Upper Cambrian trilobite biostratigraphy and taphonomy at Kakeled on Kinnekulle, Vastergotland, Sweden

100%

Terfelt F.

Acta Palaeontologica Polonica

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2003

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tom 48

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nr 3

A section through the Upper Cambrian black shales and limestones at Kakeled on Kinnekulle, Västergötland, Sweden, extends from the lower–middle part of the Agnostus pisiformis Zone into the Peltura scarabaeoides Zone. Fossils are usually preserved only in the stinkstones, but in the A. pisiformis Zone trilobites can be found also in the shales. Lithologically, the stinkstones can be subdivided into primary coquinoid limestone, which include the majority of the fossils, and early diagenetically formed limestone. The orientation of cephala and pygidia of A. pisiformis were measured on four shale surfaces and one stinkstone surface. The majority of the shields were deposited with the convex side up and showed a preferred orientation, suggesting that their positions were affected by currents. Above the A. pisiformis Zone the section comprises the Olenus/Homagnostus obesus Zone (0.30 m), the upper part of the Parabolina spinulosa Zone (0.05 m), the Peltura minor Zone (1.15 m), and the Peltura scarabaeoides Zone (2.50 m). The Leptoplastus and Protopeltura praecursor zones are missing. The Olenus/H. obesus Zone is represented only by the O. gibbosus and O. wahlenbergi subzones, whereas the O. truncatus, O. attenuatus, O. dentatus, and O. scanicus subzones are missing.

4

Stratigraphical position of the Obolus sandstones [Upper Cambrian-?Lowermost Ordovician] in Poland

80%

Bednarczyk W. S.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1998

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tom 46

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nr 1

Ograniczanie wyników

3 Acta Palaeontologica Polonica

1 Bulletin of the Polish Academy of Sciences. Earth Sciences

1 Ahlberg P.

1 Bednarczyk W. S.

1 Bengtson S.

1 Clarkson E. N. K.

1 Radwanski A.

1 Roniewicz P.

1 Szaniawski H.

1 Terfelt F.

1 2005

1 2003

1 1998

1 1963

Upper Cambrian trilobite ichnocoenosis from Wielka Wisniowka (Holy Cross Mountains, Poland)

Phosphatised olenid trilobites and associated fauna from the Upper Cambrian of Vastergotland, Sweden

Upper Cambrian trilobite biostratigraphy and taphonomy at Kakeled on Kinnekulle, Vastergotland, Sweden

Stratigraphical position of the Obolus sandstones [Upper Cambrian-?Lowermost Ordovician] in Poland