Wyniki wyszukiwania - Biblioteka Nauki

1

Catagenic ankerite replacing biogenic calcite in the Marhogda Bed [Jurassic], Sassenfjorden, Spitsbergen

100%

Krajewski K. P.

Polish Polar Research

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2002

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tom 23

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nr 1

85-99

2

The Botneheia Formation [Middle Triassic] in Edgeoya and Barentsoya, Svalbard: lithostratigraphy, facies, phosphogenesis, paleoenvironment

100%

Krajewski K. P.

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2008

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tom 29

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nr 4

319-364

3

Early diagenetic collapse and injection microstructures in phosphate nodules of the Brentskardhaugen Bed [Jurassic] in Spitsbergen

100%

Krajewski K. P.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2000

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tom 48

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nr 2

4

Diagenetic recrystallization of apatite in phosphate nodules of the Brentskardhaugen Bed [Jurassic] in Spitsbergen

100%

Krajewski K. P.

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nr 1

5

Origin of dolomite-ankerite cement in the Bravaisberget Formation [Middle Triassic] in Spitsbergen, Svalbard

63%

Krajewski K. P. , Wozny E.

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nr 3

231-248

6

Origin of cannon-ball concretions in the Carolinefjellet Formation [Lower Cretaceous], Spitsbergen

63%

Krajewski K. P. , Luks B.

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nr 3-4

7

Overthrust Carboniferous strata [Sergeijevfjellet Formation] at Lidfjellet, NW Sorkapp Land, Spitsbergen

63%

Krajewski K. P. , Stempien-Salek M.

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nr 1

8

K-Ar dating of basic intrusions at Bellsund, Spitsbergen, Svalbard

51%

Birkenmajer K. , Krajewski K. P. , Pecskay Z. , Lorenc M. W.

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tom 31

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nr 1

3-16

9

Eocene age of the Baranowski Glacier Group at Red Hill, King George Island, West Antarctica

51%

Mozer A. , Pecskay Z. , Krajewski K. P.

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nr 4

10

The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica)

51%

Tatur A. E. , Krajewski K. P. , lvalle de R. A.

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tom Vol. 55, No. 4

345-360

EN

La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known, and therefore it has been carefully investigated. The lowest part of the La Meseta Formation, at the southern bank of a palaeodelta, is represented by relics of a prograding sequence of sediments deposited in the wave-dominated part of a deltaic system in the offshore and lower and upper shoreface environments. The sequence is completed landwards by younger tidal plain sediments deposited at 40 m lower altitude in a relatively protected, central estuarine basin, which was dominated by tidal activity and influenced by periodic fluvial inflow. These strata were deposited during a late Paleocene or Ypresian/Lutetian lowstand of sea level, which might reflect a glaciation event or glacioisostatic rebound of land following deglaciation of hypothetic Antarctic inland glaciers. Forced regression of sea level and seaward expansion of a deltaic freshwater environment, led to local extinction of a unique assemblage of marine echinoderms, bryozoans, corals and brachiopods. These marine fossils, representing a thanatocoenosis, are perfectly preserved due to syngenetic goethite permineralisation. This process owed its origin to excess reactive iron coming from sulphide-rich bedrock through weathering processes and acid sulphate drainage of the neighbouring land area.

11

Early diagenetic processes in the formation of carbonate-hosted Mn ore deposit [Lower Jurassic, Tatra Mountains] as indicated from its carbon isotopic record

51%

Krajewski K. P. , Lefeld J. , Lacka B.

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nr 1

12

Type section of the Bravaisberget Formation [Middle Triassic] at Bravaisberget, Western Nathorst Land, Spitsbergen, Svalbard

51%

Krajewski K. P. , Karcz P. , Wozny E. , Mork A.

Polish Polar Research

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2007

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tom 28

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nr 2

EN

The Bravaisberget Formation in Spitsbergen embraces an organic carbon-rich, clastic sequence that reflects a general shallow shelf development of the Middle Triassic depositional system in Svalbard. New observations and measurements of the type section of the formation at Bravaisberget in western Nathorst Land allow to present detailed litho- stratigraphical subdivision of the formation, and aid to reconstruct its depositional history. The subdivision of the formation (209 m thick at type section) into the Passhatten, Somovbreen, and Van Keulenfjorden members is sustained after Mørk et al. (1999), though with new position of the boundary between the Passhatten and Somovbreen mbs. The Passhatten Mb is defined to embrace the black shale-dominated sequence that forms the lower and middle parts of the formation (160 m thick). The Somovbreen Mb (20 m thick) is confined to the overlying, calcite-cemented sequence of marine sandstones. The Van Keulenfjorden Mb (29 m thick) forms the topmost part of the formation composed of siliceous and dolomitic sandstones. The formation is subdivided into twelve informal units, out of which eight is defined in the Passhatten Mb (units 1 to 8), two in the Somovbreen Mb (units 9 and 10), and also two in the Van Keulenfjorden Mb (units 11 and 12). Units 1, 3,5,7 and 9 contain noticeable to abundant phosphorite, and are interspaced by four black shale sequences (units 2,4,6, and 8). Unit 9 passes upwards gradually into the main sandstone sequence (unit 10) of the Somovbreen Mb. The base of the Van Keulenfjorden Mb is a discontinuity surface covered by thin phosphorite lag. The Van Keulenfjorden Mb consists of two superimposed sandstone units (units 11 and 12) that form indistinct coarsening-upward sequences. The Bravaisberget Fm records two consequent transgressive pulses that introduced high biological productivity conditions to the shelf basin. The Passhatten Mb shows pronounced repetition of sediment types resulting from interplay between organic-prone, fine-grained environments, and clastic bar environments that focused phosphogenesis. The lower part of the member (units 1 to 5) contains well-developed bar top sequences with abundant nodular phosphorite, which are under- and overlain by the bar side sequences grading into silt- to mud-shale. The upper part of the member (units 6 to 8) is dominated by mud-shale, showing the bar top to side sequence with recurrent phosphatic grainstones in its middle part. Maximum stagnation and deep-water conditions occurred during deposition of the topmost shale sequence (unit 8). Rapid shallowing trend terminated organic-rich environments of the Passhatten Mb, and was associated with enhanced phosphogenesis at base of the Somovbreen Mb (unit 9). Bioturbated sandstones of the Somovbreen Mb (unit 10) record progradation of shallow-marine clastic environments. The sequence of the Van Keulenfjorden Mb (units 11 and 12) was deposited in brackish environments reflecting closure of the Middle Triassic basin in western Svalbard.

13

Clay-mineralogy of Jurassic marine black shales in Spitsbergen: a possible evidence for climate cooling during Oxfordian

45%

Bausch W. M. , Birkenmajer K. , Grunenberg T. , Krajewski K. P. , Kutyba J.

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1998

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tom 46

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nr 3-4

14

First Cenozoic glaciers in West Antarctica

38%

Birkenmajer K. , Gazdzicki A. , Krajewski K. P. , Przybycin A. , Solecki A. , Tatur A. , Yoon H. I.

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nr 1

3-12

EN

One of the most significant global climatic events in the Cenozoic was the transition from greenhouse to icehouse conditions in Antarctica. Tectonic evolution of the region and gradual cooling at the end of Eocene led to the first appearance of ice sheets at the Eocene/Oligocene boundary (ca. 34 Ma). Here we report geological record of mountain glaciers that preceded major ice sheet formation in Antarctica. A terrestrial- valley-type tillite up to 65 metres thick was revealed between two basaltic lava sequences in the Eocene- Oligocene Point Thomas Formation at Hervé Cove - Breccia Crag in Admiralty Bay- King George Island- South Shetland Islands. K-Ar dating of the lavas suggests the age of the glaciation at 45-41 Ma (Middle Eocene). It is the oldest Cenozoic record of alpine glaciers in West Antarctica- providing insight into the onset of glaciation of the Antarctic Peninsula and South Shetland Islands.