Nauki Ścisłe i Nauki o Ziemi

Acta Geologica Polonica

Zawartość

Acta Geologica Polonica | 2023 | vol. 73 | No 1

Abstrakt

Several closely-spaced phosphorite beds stand out at the Albian–Cenomanian transition in the mid-Cretaceous transgressive succession at the northeastern margin of the Holy Cross Mountains, central Poland. They form a distinctive condensed interval of considerable stratigraphical, palaeontological, and economic value. Here, we correlate the classical section at Annopol with a recently investigated section at Chałupki. We propose a new stratigraphic interpretation of the phosphorite interval, based on lithological correlations, Rare Earth Elements and Yttrium (REE+Y) signatures of phosphorites, age-diagnostic macrofossils, and sequence stratigraphic patterns. This interval has long been considered as exclusively Albian in age. However, new macrofossil data allow us to assign the higher phosphorite levels at Annopol and Chałupki, which were the primary target for the phosphate mining, to the lower Cenomanian. In terms of sequence stratigraphy, the phosphorite interval encompasses the depositional sequence DS Al 8 and the Lowstand System Tract of the successive DS Al/Ce 1 sequence. The proposed correlation suggests that lowstand reworking during the Albian–Cenomanian boundary interval played an important role in concentrating the phosphatic clasts and nodules to exploitable stratiform accumulations. Our conclusions are pertinent to regional studies, assessments of natural resources (in view of the recent interest in REE content of the phosphorites), and dating of the fossil assemblages preserved in the phosphorite interval. On a broader scale, they add to our understanding of the formation of stratiform phosphorite deposits.
Przejdź do artykułu

Autorzy i Afiliacje

Marcin Machalski
1
Danuta Olszewska-Nejbert
2
Markus Wilmsen
3

  1. Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, PL 00-818 Warszawa, Poland
  2. University of Warsaw, Faculty of Geology, ul. Żwirki i Wigury 93, PL 02-089 Warszawa, Poland
  3. Senckenberg Naturhistorische Sammlungen Dresden, Museum für Mineralogie und Geologie, Sektion Paläozoologie, Konigsbrücker Landstr. 159, D-01109 Dresden, Germany

Abstrakt

The Upper Cretaceous succession (Coniacian to lowermost Maastrichtian, with focus on the Campanian) at Petrich, Central Srednogorie Zone in Bulgaria, is described and calibrated stratigraphically based on nannofossils, dinoflagellate cysts and inoceramids. The following standard nannofossil zones and subzones are identified: UC10–UC11ab (middle to upper Coniacian), UC11c–UC12–UC13 (uppermost Coniacian to Santonian), UC14a (lowermost Campanian), UC14b TP–UC15c TP (lower Campanian to ‘middle’ Campanian), UC15d TP– UC15e TP (upper Campanian), UC16a TP (of Thibault et al. 2016; upper part of the upper Campanian), and UC16b (Campanian–Maastrichtian boundary). The base of the Campanian is defined by the FO of Broinsonia parca parca (Stradner) Bukry, 1969 and Calculites obscurus (Deflandre) Prins and Sissingh in Sissingh, 1977 (a morphotype with a wide central longitudinal suture). The Areoligera coronata dinoflagellate cyst Zone (upper lower Campanian to upper upper Campanian) is identified, corresponding to the UC14b TP–UC16a TP nannofossil subzones. The inoceramid assemblage indicates the ‘Inoceramus’ azerbaydjanensis ‘Inoceramus’ vorhelmensis Zone, correlated within the interval of nannofossil subzones UC15d TP–UC15e TP. The composition of the dinoflagellate cyst assemblages and palynofacies pattern suggest normal marine, oxic conditions and low nutrient availability within a distal shelf to open marine depositional environment during the Campanian.
Przejdź do artykułu

Autorzy i Afiliacje

Polina Pavlishina
1
Doche Dochev
1
Michael Wagreich
2
Veronika Koukal
2

  1. Department of Geology, Paleontology and Fossil Fuels, Faculty of Geology and Geography, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
  2. Department of Geology, University of Vienna, A-1090 Vienna, Austria

Abstrakt

A right theropod pedal ungual phalanx II-3 from the Campanian Williams Fork Formation of northwestern Colorado is described, and a combination of features, including the large size, tapering distal tip, robust and stout overall form, triangular cross-section, and a relatively flat ventral surface allows a confident referral to Tyrannosauridae Osborn, 1906. Although this specimen was found in a relatively southern state, the proximal articular surface of this ungual is similar to that of Gorgosaurus libratus Lambe, 1914, a taxon found in the northern state, Alberta. Although based on limited evidence, this may suggest that the range of tyrannosaurids considered endemic to the north of Laramidia extended farther south than previously thought.
Przejdź do artykułu

Autorzy i Afiliacje

Chan-Gyu Yun
1

  1. Biological Sciences, Inha University, Incheon 22212, Republic of Korea

Abstrakt

The specific name velunensis is established to encompass porcupine remains ( Hystrix Linnæus, 1758) recovered from the Pliocene site of Węże 1 in southern Poland. The studied specimen was previously assigned either to H. primigenia (Wagner, 1848) or H. depereti Sen, 2001, however it can be distinguished from these species and other fossil Hystricidae by its distinct occlusal morphology, most importantly the presence of an anterolingual flexus dissecting the anteroloph of P4. Hystrix velunensis sp. nov. was probably closely related to H. primigenia and H. depereti. A previously undescribed specimen from the nearby site of Węże 2 most probably belongs to H. refossa Gervais, 1852b, which would be the first known occurrence of this species in Poland.
Przejdź do artykułu

Autorzy i Afiliacje

Michał Czernielewski
1

  1. Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland

Abstrakt

The scope of this analysis included fluvial sediments of the low terrace of the Grajcarek stream in the Małe Pieniny Mts. (Western Carpathians). The structure of the terrace has been surveyed in five profiles. The sedimentary sequence includes alternating layers of gravel and calcareous mud with a maximum thickness of up to 2.2 m. A rich and varied malacofauna has been found in the mud. The age of the sediments was determined using the radiocarbon method. The sediments that make up the terrace cover the younger part of the Middle Holocene and the entire Late Holocene. The analysis of the malacofauna has allowed for the characterization of environmental changes. The most important of them dates back to the Middle Ages and is associated with the phase of intensive settlement in the Pieniny Mts.. It is indicated by deforestation and the related change in the composition and structure of malacocoenoses manifested by the replacement of forest communities by ones with open-country species. Gravel horizons are records of flood periods correlated with wet climatic phases. It is possible to distinguish six such phases covering the following periods: 6600–6100 y cal BP, 5500–5100 y cal BP, 4500–4100 y cal BP, 3200–2300 y cal BP, 2000–900 y cal BP and 400–200 y cal BP. They correspond to the periods of increased fluvial activity of rivers, intensification of mass movements, advances of alpine glaciers and the increase in the water level in lakes.
Przejdź do artykułu

Autorzy i Afiliacje

Witold Paweł Alexandrowicz
1

  1. AGH University of Science and Technology, Faculty of Geology, Geophysics and Environment Protection, Chair of General Geology and Geotourism, Al. Mickiewicza 30, 30-059 Kraków, Poland

Abstrakt

Lithic fragments including quartz grains occur infrequently in the shallow-marine limestone sequence of the Fatra Formation deposited in the tensional intra-shelf depression of the Central Western Carpathians during the Rhaetian. Nevertheless, their study can bring data answering questions of sources, palaeogeodynamic arrangement, and processes at the end of the Triassic. In this study, we examined optically the cathodoluminescence (CL) colours of single quartz grains from the Kardolína section (Tatra Mts, Slovakia). These colours reveal a dominance of grains derived from regionally metamorphosed and plutonic rocks. Grains of hydrothermal and pegmatite origin are less frequent. Some of the quartz grains show recycled cement rims suggesting at least a second cycle origin. This sedimentary basin was situated near to the passive margin formed by the Variscan consolidated terrains of the Vindelician Highlands. Our study of the CL colours of quartz grains contributes to the elucidation of the nature of the rocks of the vanished Vindelician mountain belt.
Przejdź do artykułu

Autorzy i Afiliacje

Marek Vďačný
1
Jozef Michalík
1

  1. Earth Science Institute of the Slovak Academy of Sciences, Dúbravská cesta 9, P.O. BOX 106, 840 05 Bratislava, Slovakia

Ta strona wykorzystuje pliki 'cookies'. Więcej informacji