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1

Wpływ wybranych barier górskich na rozkład opadów w polskich Karpatach

Cebulak E., Limanówka D., Pyrc R., Gębica P., Starkel L.

Przegląd Geofizyczny

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2018

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Z. 1-2

123--133

PL

Krawędzie gór i wyżyn stanowią istotne bariery dla przepływu mas powietrza wędrujących znad oceanów. Przy znacznej wysokości i szerokości pasm górskich mogą one stanowić zaporę trudną do przebycia albo być strefą podwyższonych opadów, zwłaszcza dla wędrujących cyklonów. Nawet niewysokie progi stanowią barierę, która objawia się w postaci prądów konwekcyjnych. Autorzy omawiają przykłady z różnych części polskich Karpat. Zwarte krawędzie Beskidu Śląskiego, Małego i Żywieckiego do 1 km wysokości wystawione są na opady ośrodków niżowych z kierunków W-NW. Ku wschodowi krawędź rozbita jest na mniejsze grupy górskie Beskidu Wyspowego, co ułatwia wnikanie opadów w głąb gór wysokich. Niekiedy chmura burzowa wędruje wzdłuż wysokiego progu (np. krawędzi Zachodnich Bieszczadów), ale i próg Pogórza wysoki tylko do 200 m sprzyja lokalnym opadom konwekcyjnym.

EN

The edges of mountains and uplands constitute significant barriers to the flow of air masses travelling from the oceans. The barriers are particularly difficult to be overcome when the height and width of mountain ranges are large, such settings can be create zones of increased rainfall, especially for roaming cyclones. Even low mountain edges form barriers which induce convectional currents. The authors discuss examples from various parts of the Polish Carpathians. The compact edges of the Silesian, Mały and Żywiecki Beskids up to 1 km high are exposed to precipitation of low-pressure systems from the W-NW directions. To the east, the edge is split into smaller mountain groups of the Beskid Wyspowy, which facilitates the penetration of high rainfall into the mountain interior. Sometimes storm clouds travel along a high edge of the mountains, e.g. along the edge of the Western Bieszczady. The edge of the foothills, only up to 200 m high, favours local convection rainfall.

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The role of orographic barriers in the origin of extreme rainfalls as exemplified by the front of high Eastern Himalaya and the low northern slope of Carpathians

Cebulak E., Gębica P., Limanówka D., Starkel L., Pyrc R.

Landform Analysis

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2018

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Vol. 36

9--17

EN

The paper discusses the role of orographic barriers in generating torrential precipitation in mountainous regions in different climatic zones, the Eastern Himalayas (tropical zone with well-developed monsoon activity) and the northern slope of the Carpathians (temperate zone with transitional climate). Attention has been paid to the different altitudes and courses of the orographic ridges as well as their location relative to the prevailing directions of influx of moist air masses. The cases analysed included torrential rains with monsoon circulation from the S–SW direction at the 2–3 km high edge of the Himalayas, with special consideration to the distance from the margin of the mountains and the exposure of the slopes. They generate frequent flood waves, landslides, debris flows and upbuilding of the alluvial cones in the foreland of the mountain barriers. The impact of the orographic barrier is significantly less marked in the Polish Carpathians. In the western part, the compact edge of the Western Beskids with an altitude of 0.5–1 km and the WSW–NEE course, exposed to moist air masses inflowing from the northern sector, is fragmented eastward into smaller mountain groups, which facilitates the penetration of moist masses of air with occurrence of prolonged precipitation into the mountains. At times, the storm cloud moves along the mountain edge (the margin of the Western Bieszczady Mts.). The marginal scarp of the Foothills has a northern exposure and a height of 150–200 m, and promotes frequent convective precipitation causing local flash floods in small streams. The cases of downpours and high discharges selected for the analysis were those for which there was available a dense network of measuring stations. An insufficient number of stations in constructing precipitation maps based on interpolation would lead to distorting the spatial image. If this were the case, then the role of slope exposure, which has an essential impact on the distribution of precipitation in mountainous regions, would be completely neglected.

3

Field trip in the semi-arid Gujarat Alluvial Plain : report

Gębica P., Wachecka-Kotkowska L., Kotkowski P.

Landform Analysis

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2017

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Vol. 35

17--20

EN

This report contains short information about the geomorphological field trip in the Gujarat Alluvial Plain. During the field trip the issues of fluvial landform and alluvial deposits of the rivers were discussed: Sabarmathi River, Mahi River, Narmada River and Karjan River. Particular attention was paid to the relief and geological structure of the Gujarat Alluvial Plain, dissected by the valleys of several rivers. The role of tectonics, sea level fluctuations and climate changes and their influence on the course of fluvial, aeolian and sea accumulation in the lower sections of river valleys was emphasized.

4

Reflection of climatic changes during interpleniglacial in the geoecosystems of South-Eastern Poland

Starkel L., Michczyńska D. J., Gębica P.

Geochronometria

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2017

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Vol. 44, no. 1

202--215

EN

About 70% of the last cold stage was taken by transitional phases of continuous fluctuations of climate and permafrost extension. All this is reflected especially well in slope types and the thickness of slope, fluvial and aeolian deposits. Very distinct and relatively fast changes took place around 33–30 ka BP: the aridification of climate with an ice sheet transgression, expansion of continuous permafrost and the onset of loess deposition. The greatest transformations of slopes and river valleys in the Carpathians and Subcarpathian Basins took place not in the coolest phases but during the Interpleniglacial. The authors exemplified a number of sites in Southern Poland documenting frequent fluctuations of climate and permafrost from that 25–30 ka long period. Calibrated dates of dated episodes correlate well with the δ18O curve from Greenland with frequent warmings. These rapid warmings are reflected in the higher rate of aggradation in valley floors and thick colluvial material deposited over slopes, both combined with a retreat of permafrost. The comparison with the Greenland 18O curve is valuable to establish a comparable chronology of events, even for such a distant area like Central-Eastern Europe.

5

Early Holocene alluvia in the lower Wisłok River valley and their chronostratigraphy in the light of radiocarbon datings and palynological analysis

Superson S., Gębica P., Michczyński A., Kołaczek P., Szczepanek K.

Geochronometria

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2017

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Vol. 44, no. 1

216--225

EN

The paper presents the results of the latest radiocarbon dating and the palynological analyses of organic sediments found in the alluvia of the Wisłok River valley between the towns of Łańcut and Przeworsk. The study conducted in the gravel pit made possible the dating of several alluvial fills of the 7–8 m high Holocene terrace and the 5–6 m high floodplain. The oldest channel alluvia and palaeochannel sediments of the 7–8 m high terrace were dated at 10 100–9300 BP (11 960–10 500 cal BP). According to the anthracological analysis the top cover of clay overbank alluvia, which bears charcoal fragments, was deposited in the Subboreal and/or the Subatlantic Phases. In the sequence of the 5–6 m high floodplain, the bottom fills of palaeochannels, dated at 10 195–9885 cal BP (probability level: 68.2%; GdS-3233: 8900 ± 95 BP ) and 11 095–10 755 cal BP (probability level: 68.2%; GdS-3228: 9575 ± 95 BP), were truncated by erosion and covered by alluvia of palaeomeanders, which were active in the 19th century. Preservation of the erosional bench of the Early Holocene organic sediments indicates the predomination of lateral migration of the river channel during the last 200 years and the formation of wide erosional floodplain that has been aggraded with recent flood alluvia. In the 20th century the floodplain aggradation was simultaneous with the deepening of the Wisłok riverbed.

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Chronostratigraphy of alluvia and age of fluvial landforms in the Carpathian Foreland during the Vistulian

Gębica P.

Studia Quaternaria

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2013

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Vol. 30, Nr 1

19--27

EN

A development of opinions on stratigraphy of alluvia and age of the Vistulian terraces in the valleys of the Carpathian foreland is presented, based mainly on publications of Professor Leszek Starkel. Studies of age of fluvial landforms and sediments of the Last Cold Stage in the Carpathian foreland have been started more than 100 years ago. Before them modern sedimentological methods and radiocarbon dating were introduced, pioneer studies of Pleistocene river terraces and sediments in the Carpathians were performed by Mieczysław Klimaszewski, and subsequently, by his student Leszek Starkel who mapped in 1950s a margin of the Carpathian Foothills as well as alluvial fans of Wisłoka, Wisłok and San rivers in the Carpathian foreland. In that time a stratigraphy of alluvial infillings in the marginal mountain zone was elaborated for the Late Vistulian and the Holocene. Starting from 1970s and basing on studies in key sites in the Wisłoka valley near Dębica, focused on palynological analyses and radiocarbon dating, general strati-graphical schemes of alluvial fills within the Vistulian terrace 15 m high and within the Holocene terrace 8-10 m high have been constructed. A comparison with the valleys in a periglacial area prowed that the Vistulian terrace 15 m high was incised before the maximum extension of the last Scandinavian ice sheet (i.e. before 20 ka BP) and the terrace 11-12 m high (with relics of braided river channels) was formed at the decline of the Plenivistulian. A final incision below the present river bed and aggradation occurred during the Late Vistulian (13-10 ka BP). The rivers changed their regime and their channel pattern from braided to large meanders-type as an effect of forest development and lower sediment load. The Younger Dryas cooling resulted in increased bedload and braiding.

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Uwarunkowania rozwoju pogrązów w aluwiach doliny Wisłoka w okolicach Rzeszowa (południowo-wschodnia Polska)

Superson J., Brzezińska-Wójcik T., Gębica P.

Przegląd Geologiczny

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2013

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Vol. 61, nr 2

127–-132

EN

The article presents the results of geological and geomorphological research concerning load-cast structures outcropping in the alluvial terrace sediments of theWisłok River in the Fore-Carpathian Erosional Valley. Given the large dimensions of these structures, reaching 1.5 m in some places, as well as their strong accumulation and diversity (i.e. drop-like and pocket-like structures), the authors attempted to establish the environmental factors that had determined the development of the structures in periglacial deposits of the Weichselian Glaciation. The structures were analysed in two accessible outcrops where sediments are represented by flood rhythmite and organic deposits, overlain by channel sands. Sandy load-cast structures occur in flood rhythmite and loamy deposits. The formation of load-cast structures probably started due to earthquakes in the Upper Pleniglacial period. The various shapes of load-cast structures were constrained by the various physical properties of the sediments and the escape of water during the deformation process.

8

Geomorphological records of human activity reflected in fluvial sediments in the Carpathians and their foreland

Gębica P.

Landform Analysis

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2013

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Vol. 22

21--31

EN

Records of human activity in valleys of the Upper Vistula River catchment and the Upper Dniester River catchment in the area of the Eastern Carpathian Foreland are synchronic and date back to the Neolithic Period. They include alluvia and colluvia in small valleys, linked with local downpours, as well as changes in large valleys, where flooding is reflected in modifications to river channels and an acceleration in the deposition of overbank facies. Among these periods are phases determined climatically (5th–7th centuries AD) and those reflecting human activity (1st–3rd centuries AD), as well as phases recording the coincidence of both factors (middle Neolithic, 10th–11th centuries AD and the Little Ice Age). The most distinct changes leading to transformation in valley slopes and bottoms are linked with the coincidence of humid climatic phases and periods of increased human impact.

9

Walory krajobrazowe Andów i ich wykorzystanie w turystyce, na przykładzie Peru, Chile i Boliwii

Gębica P.

Prace Komisji Krajobrazu Kulturowego

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2010

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nr 14

74--90

PL

W artykule przedstawiono walory krajobrazowe Andów Środkowych. Zachodnie Andy budują w większości nieczynne stożki wulkanów o kulminacjach przekraczających 6500 m n.p.m. Kordyliera Wschodnia pokryta jest w wielu miejscach lodowcami i odwadniana przez rzeki dorzecza Amazonki i La Platy. Porastają ją wilgotne lasy górskie sięgające ponad 3000 m n.p.m., w których przetrwały ruiny budowli inkaskich. W krajobrazie płaskowyżu Altiplano (3600-4500 m n.p.m.) dominują rozległe bezodpływowe równiny pokryte przez roślinność puny. W północnym Altiplano położone jest jezioro Titicaca, natomiast na południu płaskowyżu ze względu na bardzo niskie opady występują solniska. Zachodni pas wybrzeża i przedgórza Andów zajmuje pustynia Atakama. Na terenach o wysokich walorach krajobrazowych i kulturowych utworzono liczne parki narodowe. Rozmiary ruchu turystycznego, ze względu na słabo rozwiniętą infrastrukturę, są niewspółmiernie małe w stosunku do stopnia atrakcyjności turystycznej.

EN

The paper presents landscape values of the Middle Andes. The western Andes compose numerous inactive volcanic cones ranging over the 6500 m a.s.l. The Eastern Cordillera are covered by glaciers in many places and drained by rivers of the Amazon and La Plata drainage basins. The basins are covered by humid montane forests reaching an altitude over the 3000 m a.s.l., where the ruins of Inca buildings remain. The landscape of the Altiplano (3600-4500 m a.s.l.) is predominated by vast endorheic plains covered by grass and scrub vegetation (puna). In the northern Altiplano, the Titicaca Lake is located. In the southern Altiplano, due to very little precipitation there are playas with salt crusts .Western belt of coast and foreland of the Andes occupies the Atacama Desert. The national parks were established in the terrains of high landscape and cultural values. Due to the poor infrastructure, tourism development is very low and incomparable to the degree of tourist attractions.

10

Geomorfologiczne skutki oraz rola lokalnych ulew i powodzi w kształtowaniu rzeźby progu Pogórza Karpackiego (na przykładzie ulewy z czerwca 2006 r. w rejonie Sędziszowa Młp.)

Długosz M., Gębica P.

Landform Analysis

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2008

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Vol. 8

13--20

11

Osady rzeczne i roślinność interpleniglacjału zlodowacenia Wisły w dolinie Wisłoka między Rzeszowem a Lańcutem

Szczepanek K., Kalinowicz N., Gębica P.

Przegląd Geologiczny

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2007

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Vol. 55, nr 7

595-600

EN

The paper presents the results of geomorphological studies and pollen analysis performed for alluvial deposits at 2 sites situated in the Wisłok River valley. The deposits consist of thin layers of organic muds filling palaeochannels or thermo-karst lakes of the Wisłok River, dated at the Interpleniglacial (Grudziądz Interstadial) of the Vistulian Glaciation. These deposits build the lower part of a sand terrace, 8-12 m high, and outliers of this terrace buried by overbank alluvial sediments within a floodplain. The samples for pollen analysis were taken from a natural undercut in the Wisłok River channel and from a sand pit dug to a greater depth. The pollen diagrams prove the existence of trees (forest-steppe) including primarily Pinus sylvestris, Betula t. alba, Pinus cembra and Larix. The diagrams do not show a clear tendency of a plant succession and thus of any distinct climate changes. The sedimentation took place under cool, boreal climate conditions. The occurrence of several layers of organic and sand deposits in the sections does not reflect rhythmic warm/cold climatic oscillations documented in the Interpleniglacial alluvial sequences in Western European rivers, but is a result of vertical channel fluctuations and facies changes.

12

Geomorphological effects of the catastrophic drainage of artificial reservoir in the Młynówka valley at Górowo Iławeckie, Poland

Brykała D., Gierszewski P., Gębica P.

Landform Analysis

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2003

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Vol. 4

75--82

EN

The problem concerns the catastrophic flood flow caused by the breaking of the dam of the artificial reservoir in the valley of the small river Młynówka Górowska. Extensive studies were focused on the section just below the broken dam, were the geomorphological effects of that event were most noticeable. A number of erosional and accumulative forms have been distinguished. The structure and grain size of the flood deposits have been studied. The occurrence of deposit sequences characteristic of slurry-flows has been found. The rapid fall of the flood wave was associated with the deposition of the coarser deposit fractions on the sides of the valley and of the finer ones on its floor.

13

Chronostratigraphy of late pleistocene fluvial deposits in the Wisłok river valley between Rzeszów and Łańcut, south Poland

Gębica P., Bluszcz A., Pazdur A., Szczepanek K.

Geochronometria

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2002

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Vol. 21

119-128

EN

This paper presents results of absolute dating of alluvial sedimentary series forming a rendzina terrace (higher floodplain) 7-8 m high above the Wisłok River channel and a sandy terrace 8-10 m high in the Subcarpathian Pradolina section of the Wisłok River valley. The organic mud infilling fossil depressions (palaeochannels?) in the lower part of the rendzina terrace have been dated by the radiocarbon method to more than 38,500 BP. The organic series occurring within the sandy terrace yielded three ages >36,000 BP. Results of palynological analyses carried out on both sites indicate tundra or forest-tundra environments with water-filled depressions at the time of organic sediments deposition. The top of the 8-10 m high sandy terrace is built of fluvial sands and eolian cover sands with dunes in the upper-most part. Their age has been established by means of the OSL method to 11.2š0.9 ka BP. The younger alluvial inset fill is formed of sands and silts with involutions occurring under Holocene muds. They were deposited by a braided river during the Upper Plenivistulian as indicated by two other OSL dates of 22.2š2.2 ka BP and 14.0š1.5 ka BP. Within the rendzina terrace the youngest series of Vistulian age is built with peats and silts, infilling the wide depression at the foots of sandy hillocks, dated to about 11,800 BP.

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Crevassing of an inland dune during the 1998 flood in upper Vistula river valley (South Poland

Gębica P., Stachowicz-Rybka R.

Annales Societatis Geologorum Poloniae

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2002

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Vol. 72, No 2

191-197

EN

A relatively small flood in April 1998 inundated stream valleys draining the Tarnów Plateau. The flood water of one of these streams crevassed a dune. An elongated crevasse, an irregular-shaped transport zone and a crevasse splay were formed as a result. The crevasse splay consisted of several lobes, which were separated by crevasse channels. Minor fans formed at the channel outlets. All this forms were the result of rapid processes of erosion and accumulation. The dominant lithofacies in the crevasse splay sediments were fine and medium sand with horizontal (bottomset) and low-angle (topset) stratification. Trough and planar cross-stratified medium- and coarse-grained sands appear in the middle part of the vertical sequence. Most of these sediments were laid down in a high-energy environment of a sheet flow. The phase of vanishing flow left ripple marks, encountered in the highest part of the distal splay.

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Sedimentological interpretation of crevasse splays formed during the extreme 1997 flood in the upper Vistula river valley (South Poland)

Gębica P., Sokołowski T.

Annales Societatis Geologorum Poloniae

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2001

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Vol. 71, No 1

53-62

EN

The paper describes scours and crevasse splays formed at the breaks in embankments of the upper Vistula river valley during the summer 1997 flood. The scours cut into the floodplain composed of fining upward channel and overbank deposits. Erosional furrows have developed locally around the scours. In their vicinity, a thin layer of channel-ag gravel was locally laid down. Variously shaped crevasse splays were formed: finger-like, deltoidal and tongue-like. Surface relief, vege-tation and buildings controlled their geometry and sedimentary features. The lower parts of the deposits consist of fine and medium sands with horizontal and low-angle stratification. Higher in the sequences medium and coarse sands with pebbles display planar cross-stratification. Mud balls and black oak trunks redeposited from older alluvia are common. The whole succession represents sheet-flow sediments with partly channelized flow. Locally, at the top, coarse sands, pebbles, mud balls and boulders embedded in silty-sandy matrix occur, representing slurry-flow deposits. Also present were sediments composed of alternating sands and mud pebbles. The vanishing flow phase is marked by occasional ripple marks encountered in the top part of the sequence. Around the flow obstacles (plants, buildings) sand shadows were formed, composed of fine and medium sands with horizontal stratification in the lower parts and ripple cross-lamination along with climbing cross-lamination in the upper parts. The top part included medium and coarse sands with planar cross-stratification. Most of the studied sequences showed coarse-upward grading which is not the effect of changes in the energy of flood waters but originates from the supply of all the time coarser material from the successively deepening scours.