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Eemian–Weichselian Pleniglacial fluvial deposits in S Poland (an example of the Vistula River valley in Kraków)

Sokołowski T., Wacnik A., Woronko B., Madeja J.

Geological Quarterly

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2014

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Vol. 58, No. 1

71--84

EN

A fragment of the middle terrace in the VistulaRivervalley, nearby the railway station in Kraków, is formed by fluvial channel and overbank deposits of the PrądnikRiver, which bear a record of various environments affected by changing climatic conditions. The sedimentary succession includes two complexes that differ in lithofacies. The older complex comprises fining-upward deposits (channel sand and gravelly sand with medium- and large-scale trough cross-stratification) and, less frequently, sand with planar cross-stratification overlain by silt with intercalations of biogenic deposits of abandoned channels. Vegetation accompanying the deposition of biogenic layers was typical of boreal coniferous forests, dominated by Pinus sylvestris with a small admixture of Larix, Pinus cembra, Picea, Betula, and Populus. Periodically, the landscape passed into open areas overgrown by woody tundra. The complex developed as a result of activity of a meandering river under conditions of a moderately cool climate. The younger complex includes the sand lithofacies with horizontal stratification and low-angle cross-stratification, overlain by alternating sands and silts. The topmost part is represented by sands with large- and medium scale planar cross stratification. Lack of biogenic deposits and considerable amount of frosted quartz grains in alluvial sediments indicate aeolian processes of greater intensity, periglacial conditions and evolution towards a braided or transitional river. Pollen successions, absolute dating and studies of structural and textural features of the sediment suggest that the time of its deposition may be estimated at a range between the close of the Eemian Interglacial and the Weichselian Middle Pleniglacial (OIS 5e–OIS 3).

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Changes of natural environment in Kraków downtown - its chronology and directions. Case geoarchaeological studies of Krupnicza street site

Sokołowski T., Wacnik A., Wardas M., Pawlikowski M., Pazdur A., Madeja J., Woronko B., Madej P.

Geochronometria

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2008

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Vol. 31

7-19

EN

Sediments exposed in a construction excavation form a sequence: alluvial deposits > black soil > made ground. Peat-like deposits, organic muds and occasionally sand occur between the soil and the made ground. High aeolization of alluvial sediments allows relating their age to the Late Vistulian. The sediments were eroded and in the washout at first organic muds were deposited and subsequently sands. The lowest layer, radiocarbon-dated at 4510±60 uncal. years BP (Gd-12724), can be probably linked to climate moistening at the transition between the Holocene Atlantic and the Subboreal period. Pollen grains found in muds, black soil and peat-like deposits reflect the changes of local plant cover from dominated by pine woodlands (at the transition between the Atlantic and the Subboreal period) to strongly deforested with single trees, meadows, small crop fields and gardens in the Medieval period. Palynological results describing the character of vegetation might have been influenced also by direct human activity on site, e.g. by storage of wood and branches (then used as construction material or fuel), crops, fodder or waste. Microartefacts found in soil suggest metal processing in the vicinity during the Bronze Age. In the made ground, which has been accumulating since the 14th century, quartz, clay minerals and micas were identified together with fragments of bricks, concrete, ceramics, bones, slag, charcoal, organic matter, limestone fragments and metals. Horizons enriched in slag fragments are also high in metals: Fe, Mn and Pb, which reveal a twofold increase in metal processing activity.

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Depositional processes in a Late Miocene posttectonic basin: Terravecchia Formation, Scillato Basin, Sicily

Abbate B., Incandela A., Renda P., Ślączka A.

Annales Societatis Geologorum Poloniae

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1999

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Vol. 69, No. 1-2

27-48

EN

Terravecchia Formation in the Scillato Basin is a good example of development of a post-tectonic basin. Practically continuous exposures across that basin give the rare possibility to observe the lateral distribution of lithofacies and gradual changes of sedimentary succession from an alluvial fan, fluvial plan to lacustrine and, eventually, to marine setting. The alluvial fan deposits are generally represented by polymictic, disorganised or crudely organised conglomerates representing mainly flow and debris flow deposits. The fluvial plain association is characterized generally by cross-bedded sandstones with streaks of conglomerates laid down within a channel bar system. Flood-plain deposits are subordinate. Sedimentary structures suggest deposition in a braided river. The fluvial plain association pass laterally to lacustrine/fluvial plain deposits represented by grey to pinkish mudstones with channelised sandstones. As an effect of subsidence the Scillato Basin was invaded by marine/brackish environment, and marly mudstones and siltstones with subordinate sandstones were deposited. That variability of sedimentary facies can be explained by vertical tectonic movements.

PL

Późnomioceńska formacja Terravecchia zachowana w basenie Scillato, stanowi dobry przykład rozwoju basenu posttektonicznego. Ciąg bardzo dobrych odsłonięć w poprzek basenu pozwolił na szczegółowe obserwacje rozkładu litofacji, struktur sedymentacyjnych oraz asocjacji facjalnych i ich wzajemnych związków. Wyróżnionych zostało kilka środowisk sedymentacyjnych, od stożka aluwialnego, przez rzekę roztokową po środowisko jeziorne i morskie. Osady stożka aluwialnego reprezentowane są przez czerwone i żółte, polimiktyczne zepieńce, o strukturach zarówno bezładnych jak i uporządkowanych, powstałe w wyniku działania prądów i spływów rumoszowych. Osady rzeki roztokowej to głównie przekątnie warstwowane piaskowce związane z różnego rodzaju łachami piaszczystymi. Mułowcowe osady równi zalewowych zachowały się tylko sporadycznie. Osady rzeczne przechodzą lateralnie w mułowcowe osady jeziorne z licznymi osadami kanałowymi w ich dolnej części. Pod koniec rozwoju basenu, w rezultacie subsydencji tektonicznej, nastąpiła ingresja morska i powyżej osadów rzeczno-jeziornych rozpoczęła się sedymentacja osadów brakiczno-morskich z poziomami fauny.