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Stop 17. Leszna Górna quarry – carbonate flysch (lowermost Cretaceous, Berriasian)

Krobicki Michał, Starzec Krzysztof, Waśkowska Anna

Geotourism / Geoturystyka

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2023

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nr 3-4 (74-75)

56--61

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Stop 1. Skrzydlna quarry – olistostrome-bearing succession of the Menilite Beds (Eocene-Oligocene)

Wendorff Marek, Starzec Krzysztof, Siemińska Aneta

Geotourism / Geoturystyka

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2023

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nr 3-4 (74-75)

18--28

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Permian versus Jurassic geotectonic position of the Lhasa block – facts and controversies

Krobicki Michał, Golonka Jan, Starzec Krzysztof, Iwańczuk Joanna

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

38--38

EN

The Cimmerian Continent (or Cimmeria, Cimmerian terrane, Cimmerian blocks) was detached from eastern Gondwana in the Late Paleozoic as a sliver/ribbon of continental strip rifting elements. Recently, these elements belong to an almost continuous long belt (ca. 13,800 km) from central Italy trough Greece, Turkey, Iran, Afghanistan, Tibet, SW China, Myanmar, Thailand up to Indonesia (Sumatra). The palaeogeographic position and relationship of some elements during Permian-Mesozoic times is still matter of discussion. The Qiangtang and Lhasa blocks (present-day Tibet) belong to these elements and their location in space and time and their relationship causes a lot of controversies. Their position alongside eastern Gondwana in the mid-Early Permian (ca. 290–285 Ma) are suggested both by palaeomagnetic and facies studies. Palaeomagnetic studies indicated this position one decade ago, which has been confirmed by recent studies. The Cimmerian Continent [Iran (Alborz)-Qiangtang-Baoshan-Tengchong-Sibumasu] was separated from the Gondwanian part of Pangea during mid-Early Permian time by rifting and drifting. Northwards migration of it took place during Permian-Triassic times caused wide opening of the Bangong‐Nujiang Tethyan Ocean and closing of the Paleotethys Ocean but the Lhasa block was still southern margin of the Bangong‐Nujiang Ocean. The Triassic Indosinian Orogeny has been one of the most spectacular geotectonic event reflecting collision of this continent with Indochina block and closure of the Paleotethys Ocean. The separation of the Lhasa block from Gondwana is enigmatic but most probably took place during earliest Jurassic times. This separation was followed by quick shift northward. Intensive sedimentological studies of the Late Triassic (Carnian-Norian) several flysch-type turbidites in the eastern Tethyan Himalaya (e.g. Qulonggongba, Pane Chaung, Langjiexue, Quehala, Duoburi formations/groups) indicate that their provenance was connected with Lhasa block, which has been their source area during early-stage evolution of the Neotethys. The late Early Permian rift-related basaltic magmatism in northern Baoshan (in SW China) and sourrounding regions was connected with first step of separation from Gondwana margin of this block (together with South Qiangtang and Sibumasu blocks and simultaneously with opening of the Bangong‐Nujiang Ocean before the Middle Permian) – independently of Lhasa block which was separated later, the most probably during Late Triassic or Triassic/Jurassic transition time with very wide space of the Bangong‐Nujiang Tethyan Ocean between Qiangtang and Lhasa blocks (2,600 km ±710 km – 23.4° ±6.4° during the Middle Jurassic with its maximum width in the Late Triassic). From the palaeobiogeographic point of view, the worldwide distribution of Pliensbachian-Early Toarcian large bivalves of the so-called Lithiotis-facies, dominated by Lithiotis, Cochlearites, Litioperna genera revealed by the authors’ studies, indicates very rapid expansion of such type of bivalves alongside southern margin of Neotethys, and could be good evidence of palaeogeographic position of the Lhasa block in this time. Himalayan and Tibetan (Nyalam area) occurrences of Lithiotis and/or Cochlearites bivalves could help to place the Lhasa block nearby the Gondwana during Early Jurassic times. This palaeobiogeographic research contradict another interpretation based on different fossils (Permian fusulinids and brachiopods) interpreted as subtropical fauna, which could occur in low subtropical latitudes together with other parts of the Cimmerian Continent.

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Dzieje Oddziału Krakowskiego Polskiego Towarzystwa Geologicznego

Waśkowska Anna, Sikora Rafał, Starzec Krzysztof, Ślączka Andrzej

Przegląd Geologiczny

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2022

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Vol. 70, nr 4

292--299

EN

The Kraków Branch of the Polish Geological Society (PGS) was established in 1922 and is the oldest and largest regional branch of the PGS. Initially, it was managed directly by the PGS Main Board, and from 1963, it has its own board. From the beginning, it has been one of the most active centres of the PGS and supported the work of the PGS management board in organizational activities in the country and in foreign cooperation. During World War II, its members gave secret lectures, and in the post-war period, they took part in reactivating the PGS activities and establishing both other branches and most of the specialist sections of PGS. The branch organized about 30% of all annual PGS Scientific Meetings and several dozen other scientific symposia and popular scientific sessions. It was the centre to initiate the organization of Polish Geological Congresses in the 21st century. The Kraków Branch includes representatives of all scientific institutes from Kraków and beyond, dealing with Earth sciences.

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Campanian-Paleocene Jaworzynka Formation in its type area (Magura Nappe, Outer Carpathians)

Waśkowska Anna, Golonka Jan, Starzec Krzysztof, Cieszkowski Marek

Acta Geologica Polonica

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2021

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Vol. 71, no. 3

345--370

EN

The Campanian-Paleocene Jaworzynka Formation, a part of the Magura Nappe succession in the Polish Outer Carpathians, is described in terms of its detailed litho- and biostratigraphy. The formation stretches along the marginal part of the Siary Unit, from the Jaworzynka stratotype area in the Silesian Beskid Mts up to the Mszana Dolna area in the Beskid Wyspowy Mts. Its equivalent in the Moravskoslezské Beskydy Mts of the Czech Republic is the Soláň Formation. In the stratotype area, the formation displays complex structure. We distinguish four lithological units, i.e., Biotite Sandstone and Shale (I), Shale (II), Mutne Sandstone Member (III) and Thin-bedded Turbidite (IV) and provide the first detailed biostratigraphy of particular units. The first unit forms the most prominent part of the formation. It was deposited in the Middle Campanian-earliest Maastrichtian within the upper part of Caudammina gigantea Zone up to the lower part of the Rzehakina inclusa Zone. The second unit occurs only locally and its age is limited to the Maastrichtian, to the Rzehakina inclusa Zone. The third unit is composed of thick-bedded sandstones that in some parts may form more than the half of the total thickness of the formation. It is Late Maastrichtian-Danian in age and is placed in the upper part of the Rzehakina inclusa Zone and the lower part of the Rzehakina fissistomata Zone. It is usually covered by a thin package of thin-bedded turbiditic sandstone and shales of Danian-Thanetian age with foraminifera of the Rzehakina fissistomata Zone.