Browsing by Author "Surmik, Dawid"

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Access status: Open Access ,
A regurgitalite of the Middle Triassic (Muschelkalk) from Upper Silesia (Poland)
(Wydawnictwa AGH, 2021) Niedźwiedzki, Robert; Surmik, Dawid; Chećko, Agnieszka; Salamon, Mariusz A.
A bromalite from the Middle Triassic (Muschelkalk) of southern Poland, Sadowa Góra Quarry, is herein described and interpreted as a regurgitalite. The fossils occurring within the regurgitalite are angular and have sharp edges. They are represented by common fragments of thin-shelled bivalves as well as rare crinoid and gastropod remains. The composition of the collected inclusion is different from that of the host rock. There are many candidates that could have produced the regurgitalite, including durophagous sharks, marine reptiles, the actinopterygian Colobodus, or nautiloids. Our finding adds to the emerging evidence of durophagous predation in the Triassic sea of Polish part of the Germanic Basin. It is the second record of a regurgitalite from the Muschelkalk of Upper Silesia.
Access status: Open Access ,
An awkward contaminant: are mercury concentrations in historically collected fossils a result of storage conditions?
(Wydawnictwa AGH, 2022) Surmik, Dawid; Cabała, Jerzy; Balin, Katarzyna; Szade, Jacek
High concentrations of mercury (Hg), reaching astonishing values in two cases, have recently been detected in Middle and Late Triassic fossil reptile bones, housed for over 100 years in several Polish museum collections. Since no correlation between either the life modes of these taxa or their burial environment was observed, the studied contaminations seem to be associated with housing conditions. The specimens were kept for an extended amount of time in boxes, in which they were stored soon after finding. A proximity of mercury-containing materials, like mercury fulminate, and unstandardized conditions of storage and conservation of the remains may result in contamination of porous bone with mercury. A detailed knowledge about the housing history of old museum collections has great importance to their prospective studies.
Access status: Open Access ,
Ophiuroids from the Middle Triassic (Muschelkalk) of Sadowa Góra, Jaworzno (southern Poland)
(Wydawnictwa AGH, 2020) Surmik, Dawid; Salamon, Mariusz A.; Chećko, Agnieszka; Kędroń, Karolina
Ophiuroids belonging to Aspiduriella sp., Aspiduriella similis (Eck), and Arenorbis sp. are described from the Middle Triassic (Muschelkalk) strata of the Sadowa Góra Quarry (Jaworzno) in southern Poland. This is the only Polish location where three taxa of these ophiuroids have been found in one stratigraphic horizon (1$^{st}$ Wellenkalk). To date, only single taxa have been found in the Triassic sections of the eastern part of the Germanic Basin. Finally, other ophiuroid mass aggregations also known from Poland are presented.