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1

New data on pre-Eocene karst in the Tatra Mountains, Central Carpathians, Poland

Gradziński M., Jach R., Hercman H.

Geological Quarterly

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2016

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Vol. 60, No. 2

291-300

EN

Sparry limestone, ferruginous muddy limestone and limestone breccia have been found in the Western Tatra Mts. They occur within Jurassic rocks of the Choč Nappe just below red conglomerates of probable Eocene age. The deposits found bear strong resemblance to the infill of subterranean karst forms. They differ significantly from Quaternary karst deposits of the Tatra Mts. The δ18O values of spelean carbonates suggest crystallisation at relatively high temperatures (over 20°C) whereas their relatively negative δ13C values imply the presence of soil-derived CO2 linked with vegetation dominated by C3 pathway plants. The karst forms and their infill were formed before the Eocene transgression, which shows unequivocally that the Tatra Mts. were subjected to karstification at that time.

2

Radiocarbon dating of fossil bats from Dobšina Ice Cave (Slovakia) and potential palaeoclimatic implications

Gradziński M., Hercman H., Peresviet-Soltan A., Zelinka J., Jelonek M.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 3

341--350

EN

Although Dobšina Ice Cave (DIC, Carpathians, Slovakia) is located outside the high-mountain area, it hosts one of the most extensive blocks of perennial subterranean ice, the volume of which is estimated at more than 110,000 m3. Frozen bat remains were found in the lowermost part of the perennial ice block. They belong to Myotis blythii (Tomes) and the M. mystacinus morpho-group. The radiocarbon dating of bat soft tissues yielded ages of 1266–1074 cal. yr BP and 1173–969 cal. yr BP. The undetermined bat, found in the same part of the ice section in 2002, was previously dated at 1178–988 cal. yr BP (Clausen et al., 2007). The dates testify that the ice crystallized at the turn of the Dark Ages Cold Period and the Medieval Warm Period. The calculated accumulation rate of cave ice varies between 0.7 cm/year and 1.4 cm/year at that time, and is similar to the present ice accumulation rate in DIC. Constant crystallization of ice during the Medieval Warm Period is hypothesized to reflect dry summer seasons since the supply of relatively warm water in the summer is one of the key factors causing the erosion of cave ice. The uppermost sample was covered with 20.6 m of ice. Between ca 1065 cal. yr BP and the present day, the ice grew faster than between ca 1210 yr BP and ca 1065 yr BP by a factor of 1.3–1.8. This may have resulted from conditions favourable for ice accumulation during the Little Ice Age.

3

Holocene tufa in the Slovak Karst : facies, sedimentary environments and depositional history

Gradziński M., Hercman H., Jaśkiewicz M., Szczurek S.

Geological Quarterly

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2013

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Vol. 57, No. 4

769–-788

EN

Several tufa complexes are known in the Slovak Karst which is a typical karst area of a temperate climate. This area is built of Mesozoic carbonates, mainly Triassic in age. The karst systems drain carbonate plateaux and lead water to resurgences located in valleys which are up to 300 m deep. Below the resurgences there are Holocene fossil tufa deposits that exceed 12 m in thickness. The tufas include stromatolite, moss, phytoclastic, oncoidal, and intraclastic facies. Extensive barrages which once dammed the upper reaches of the streams were formed in narrow valleys. They are composed predominantly of moss facies and stromatolites, with subordinate oncoidal and phytoclastic facies. Phytoclastic, oncoidal and intraclastic facies are dominant in dammed segments of streams, and include gastropod shells and charcoal fragments. Some small moss cushions are also developed. Barrages and dammed areas formed in a longitudinal fluvial depositional system. Conversely, below resurgences located on plateau slopes tufas of a perched springline depositional system were formed. These comprise deposits of prograding cascades constructed by moss, phytoclastic and stromatolitic facies. Presently, the tufas analysed are inactive. They stopped growing in the Late Holocene time, after which there was abrupt incision of the streams. This caused downcutting into Holocene tufas, in some places reaching Mesozoic bedrock. At present tufa is being precipitated from streams in all the sites studied.

4

Needle-fibre calcite and nanofibres as components of Holocene fissure-filling carbonates in southern Poland

Gradziński M., Jach R., Górnikiewcz R.

Annales Societatis Geologorum Poloniae

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2013

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Vol. 83, No. 3

229–242

EN

The article deals with the carbonates, filling fissures in limestone bedrock and presently exposed in a south-facing rock wall of Kramnica hill (Pieniny Klippen Belt, southern Poland). The carbonates are composed of (i) needle-fibre calcite crystals, (ii) carbonate nanofibres, (iii) carbonate nanoparticles, and (iv) micrite and sparite calcite crystals. Detrital grains from the carbonate bedrock occur subordinately. The spatial relationships of the components give documentation that the nanofibres were formed simultaneously with or slightly later than the needle-fibre calcite crystals. There exists a continuous chain of forms from nanoparticles to elongated nanofibres. This, in turn, indicates that all the above morphological forms are related genetically. In relatively wide fissures, the carbonates studied formed stepped microterracettes, similar to those of speleothems, mainly of moonmilk type. Conversely, narrow fissures are completely filled with carbonates, which display parallel lamination. The carbonates were formed in the late Holocene. However, “dead carbon effect” precludes the possibility of any precise dating of them. Their δ13C and δ18O values are in ranges from -5.1‰ to -3.8‰ and from -6‰ to -4.7‰, respectively. The carbonates studied bear a strong resemblance to soil and spelean, moonmilk-type carbonates. This indicates that continuity exists between the depositional environments of soil and spelean carbonate.

5

Peculiar calcite speleothems filling fissures in calcareous sandstones and their palaeohydrological and palaeoclimatic significance: an example from the Polish Carpathians

Gradziński M., Duliński M., Hercman H., Górny A., Przybyszowski S.

Geological Quarterly

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2012

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Vol. 56, No. 4

711--732

EN

Peculiar calcite speleothems developed in fissures in the Cergowa Sandstones were found in the Klęczany Quarry (Polish Western Carpathians). They represent flowstone and stalactites, rafts and various sparry crusts. Such speleothems, especially phreatic ones, are uncommon in the Outer Carpathians that are composed mainly of siliciclastic rocks of flysch type, with only limited calcium carbonate content. The speleothems analysed grew in vadose and phreatic conditions as well as at the air-water interface. Phreatic speleothems and thin rafts comprise calcite crystals of eccentric morphology. Based on their stable isotope composition the majority of the speleothems form two clusters. The first is characterized by d18O values between –9.8 and –8.5‰ and of d13C values between –5.7 and –0.6‰ whereas the second cluster of samples yields d18O values between –9.4 and –7.3‰ and d13C values from –11.5 to –9.7‰. Speleothems grew between 230+14–13 ka and Holocene time. Phreatic speleothems, including massive rafts, precipitated from ascending water of deep circulation whereas vadose and water table speleothems crystallized from local infiltration water charged with soil CO2. Mixing of both waters in the shallow phreatic zone is plausible.

6

Formation of calcite by chemolithoautotrophic bacteria – a new hypothesis, based on microcrystalline cave pisoids

Gradziński M., Chmiel M.J., Motyka J.

Annales Societatis Geologorum Poloniae

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2012

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Vol. 82, No. 4

361–-369

EN

A new mechanism, stimulating the precipitation of calcite, is postulated. The supersaturation with respect to carbonate minerals is changed, as a result of CO2consumption by chemolithoautotrophic, hydrogen-oxidizing bacteria. This mechanism controls the growth of atypical, microcrystalline cave pisoids in Perlová Cave, in Slovakia. The pisoids grow under calm conditions in rimstone pools, where they are bathed continuously in stagnant water. The water is supersaturated, with respect to calcite and aragonite. The bacteria inhabit the outer parts of the pisoids, covered by biofilms. The biofilm influences the supply of the Ca2+ ion, slows down the precipitation rate, and favors calcite precipitation over that of aragonite. The calcite initially precipitates as bacterial replicas, which further act as seeds for the growing calcite crystals. This process leads to the obliteration of the primary, bacterial fabrics. Since hydrogen-oxidizing bacteria occur in a wide spectrum of natural habitats, the mechanism of calcification, postulated above, also may operate in other environments.

7

High (ultrahigh) pressure metamorphic terrane rocks as the source of the detrital garnets from the Middle Jurassic sands and sandstones of the Cracow Region (Cracow-Wieluń Upland, Poland)

Meres S., Aubrecht R., Gradziński M., Sykora M.

Acta Geologica Polonica

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2012

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Vol. 62, no. 2

231-245

EN

The Middle Jurassic (Upper Bathonian/Lower Callovian) sands and sandstones of the Cracow.Wieluń Upland contain detrital garnets with high contents of the pyrope molecule (30.73 mol %). The predominance of detrital pyrope garnets, and inclusions represented mainly by omphacite and kyanite, show that the garnets were derived from high (ultrahigh) pressure (H/UHP) metamorphic terrane rocks (garnet peridotites, eclogites and granulites). Their source is unknown. The Moldanubian Zone of the Bohemian Massif is closely comparable. However, the terranes between this zone and the Cracow-Wieluń Upland are dominated by almandine garnets. The relatively low proportion of almandine garnets in the examined samples indicates that transport of the detrital material could not have been from a far distant source as the garnet assemblage would otherwise be strongly dominated by almandine. A less distant possible source could have been the Góry Sowie Mts., which incorporate UHP/HP metamorphic rocks, but the exposed areal extent of these rocks is too small. It is possible that larger portions of these metamorphic rocks are buried beneath the Cenozoic cover and might have earlier represented a larger source area. Reworking of the entire heavy mineral spectra from older clastics is improbable because of the low maturity of the heavy mineral assemblages (higher proportion of less stable minerals). The source area therefore remains unknown. Most probably it was formed by primary crystalline complexes of lower crust to mantle origin, outcrops of which were not far distant from the area of deposition. Similar detrital garnet compositions were also recorded in the Outer Western Carpathians (Flysch Zone, Pieniny Klippen Belt), i.e. the crustal segments which formed the Silesian and Magura cordilleras; the Czorsztyn Swell was also formed by similar rocks.

8

Morphotype variation of orthophragminids as a palaeoecological indicator: A case study of Bartonian limestones, Pod Capkami Quarry, Tatra Mts, Poland

Machaniec E., Jach R., Gradziński M.

Annales Societatis Geologorum Poloniae

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2011

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Vol. 81, No 2

199-205

EN

Nummulites-Discocyclina bioclastic packstone and Discocyclina rudstone occur in the transgressive sequence of the Middle–Upper Eocene deposits in the Tatra Mts. The succession of the studied facies is a direct response to a rapid environmental change, related to progressive deepening. Facies transition from Nummulites- Discocyclina bioclastic packstone of proximal mid-ramp to Discocylina rudstone of distal mid- and outer-ramp is an exemplary record of a deposition during deepening conditions. Increasing of diversity of the genus Discocyclina, decreasing of diversity of other foraminifera up the section and vertical variation of orthophragminid mor- photypes from the ovate- through saddle- to the disc-shaped tests are related to deepening and shadowing of the depositional environment.

9

Ascending speleogenesis of Sokola Hill: a step towards a speleogenetic model of the Polish Jura

Gradziński M., Hercman H., Kicińska D., Pura D., Urban J.

Acta Geologica Polonica

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2011

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Vol. 61, no. 4

341-365

EN

The paper deals with the origin of caves in Sokola Hill (Polish Jura). The caves abound in solution cavities in the walls and ceilings, many of them arranged hierarchically, some others arranged in rising sets. Blind chimneys and ceiling half-tubes are also present. These features collectively indicate that the caves originated under Phreatic conditions by an ascending flow of water, probably of elevated temperature. Phreatic calcite spar, crystallized from water of elevated temperature, lines the cave walls. During the formation of the caves the Jurassic limestone aquifer was confined by impermeable cover. Three possible scenariosfor the origin of the caves are suggested. The firstscenario pointsto formation of the caves during the Palaeogene prior to the removal of the confining Cretaceous marls. The second connectsthe origin of the caves with regional palaeoflow driven by tectonic loading by Carpathian nappes to the south, while the third refers to local topographically driven palaeoflow. Both the second and third scenarios assume that the Polish Jura had a cover of Miocene impermeable clastics. All the scenarios account for the origin of the caves in Sokola Hill and explain the common occurrence of ascending caves throughout the Polish Jura. In the subsequentstages of evolution the caves were partly filled with various deposits. Conglomerates composed of Jurassic limestone clasts, quartz sands and sandstones are preserved as erosional remnants, locally covered by or interfingered with calcite flowstones. The clastic deposits were laid down by surface streams that invaded the caves earlier than 1.2 Ma. The caves were not invaded by water from Pleistocene glaciers, which is proved by the assemblage of heavy minerals in the cave clastics.

10

The first dating of Cave Ice from the Tatra Mountains, Poland and its implication to palaeoclimate reconstructions

Hercman H., Gąsiorowski M., Gradziński M., Kicińska D.

Geochronometria

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2010

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Vol. 36

31-38

EN

Lodowa Cave in Ciemniak, which belongs to the dynamic ice cave type, contains the biggest perennial block of cave-ice in the Tatra Mountains. The ice represents congelation type, since it originates from freezing of water which infiltrates the cave. Two generations of ice have been recognized in this cave. They are divided by the distinct unconformity. The ice building both generations is layered. Two moths which were found in the younger generations were sampled and dated by 14C method yielding 195 ± 30 and 125 ± 30 years. Bearing in mind the position in the section and the fact that the cave ice has waned since the 20s of the last century, the age is 1720-1820 AD and 1660-1790 AD respectively. It proves that the ice was formed during the Little Ice Age. Hence, the erosion boundary which underlies this generation records the degradation of ice before the Little Ice Age most probably during the Medieval Warm Period. The ice volume in the cave was substantially smaller before the Little Ice Age than it is today, despite the clear tendency to melting, which has been recognized since 20s of the last century. The older generation of ice is supposed to have its origins in a cold stage between the Atlantic period and the Medieval Warm Period.

11

Siliciclastic micro- stromatolites in a sandstone cave: role of trapping and binding of detrital particles in formation of cave deposits

Gradziński M., Chmiel M. J., Lewandowska A., Michalska-Kasperkiewicz B.

Annales Societatis Geologorum Poloniae

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2010

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Vol. 80, No 3

303-314

EN

The article deals with finely laminated microstromatolites composed of detrital siliciclastic particles, mainly quartz, feldspars and clay minerals, lining the walls of W Sopotni Wielkiej Cave (Polish Outer Carpa- thians). Newly precipitated mineral phases do not contribute to their growth. The microstromatolites cover vertical and overhanging walls of the cave. They form subhorizontal ripples and tongue-shaped stepped microterracettes. The stromatolites are constructed by bacteria and Actinomycetes. Seven morphotypes of micro-organisms have been distinguished. Trapping and binding of detrital particles result in the microstromatolite growth. The growth is influenced by the relatively close distance to the soil cover which provides detrital mineral particles and by the presence of gravitationally widened fissures which guide the water transporting mineral particles down to the cave. The particles are transported only during wet periods. The episodic supply of the particles results in visible lamination of microstromatolites. The microterracettes form in zones of increased water-flow. The lack of auto- chthonous components most probably reflects too low saturation of water to precipitate any minerals.

12

Kras tatrzański - rozwój wiedzy w ostatnich trzydziestu latach

Gradziński M., Hercman H., Kicińska D., Barczyk G., Bella P., Holúbek P.

Przegląd Geologiczny

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2009

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Vol. 57, nr 8

674-684

EN

The paper presents the latest results of studies on karst phenomena in the Tatra Mountains. Three periods of pre-Neogene karstification have been identified, that is Middle to Late Triassic, Albian and Palaeocene to Early Eocene. Up to now, 1168 caves have been registered in the Tatra Mts: 805 in Poland and 363 in Slovakia. Their total length exceeds 175 km. Wielka Śnieżna Cave from Mt. Małołączniak (Czerwone Wierchy Massif), with its total length of more than 23 km and vertical extent 824 m, is the deepest and longest of those hitherto found in this region. In the recent years the idea on hydrothermal origin of a number of caves in this area has been put forward. Other caves formed under phreatic conditions display numerous phreatic loops. Therefore, spatial distribution of these caves does not mark the former position of a water-table. The direction of palaeoflow was generally similar to that of the modern karst drainage. The U-series dating of speleothems has revealed that the phreatic stage in development of some caves ended earlier than 1.2 Ma. The mean rate of valley deepening during the last 200 ka was estimated at 0.2-0.3 m/ka. The microbial origin of moonmilk deposits, which are very common in the Tatra caves, has been put forward. The analyses of speleothem isotopic composition show that not only temperature but also migration path of feeding water can govern the delta exp.18 values. The palaeontological and archaeological findings in the Tatra caves are scarce. Presently, the cave lion bones and sculls accompanied by numerous bones of a cave bear were found in a Slovak cave (Medvedia jaskyňa). Dye-tracing tests, both in Polish and Slovak parts of the mountains, have been conducted to confirm connections between particular sink-holes and karst springs. The stable isotopic composition of karst-spring water and water residence time based on tritium content have been studied as well.

13

Mysterious high-pyrope detritic garnets in the Middle Jurassic clastics of the Cracow region

Aubrecht R., Meres S., Gradziński M., Sykora M.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2009

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T. 35, z. 3/1

9-15

PL

W celu rozpoznania składu minerałów ciężkich środkowojurajskich piasków i piaskowców, analizie poddano utwory tego wieku z kilku odsłonięć okolic Krakowa (Dębnik, Dębnik-Czatkowice, Racławice, Paczółtowice). Wykazano w ich obrębie wysoki udział minerałów z grupy granatu, wskazując na duże podobieństwo do minerałów tego typu znanych z zewnętrznych Karpat Zachodnich. Tym niemniej bezpośrednie wskazanie obszaru źródłowego tych minerałów nie jest możliwe, a stwierdzić można jedynie, że ten enigmatyczny region obfitował w granulity, eklogity i perydotyty.

14

Artesian origin of a cave developed in an isolated horst: a case of Smocza Jama (Kraków Upland, Poland)

Gradziński M., Motyka J., Górny A.

Annales Societatis Geologorum Poloniae

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2009

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Vol. 79, No 2

159-168

EN

The cave of Smocza Jama located in the centre of Kraków is developed in the Wawel Horst built of Upper Jurassic limestone and surrounded by grabens with Miocene clays. The cave is composed of two series: the old one has been known for ages and the new one was discovered when an artificial shaft was mined in 1974. The new series comprises small chambers separated by intervening thin walls while the old series consists of three connected together spatial chambers. The cave abounds in extensively developed solution cavities – cupolas and ceiling pockets. The internal fine-grained deposits, predominantly representing clay fraction are built of illite, mixed layer illite-smectite, kaolinite and iron oxides. They are probably the residuum after dissolution of Jurassic limestone. The cave originated in phreatic condition due to water input from below. The new series represents juvenile stage of cave evolution. The water rose through fissure-rifts located in chamber bottoms, circulated convectionally within particular chambers, finally led to bleaching of intervening walls, and hence to connection of the neighbouring chambers. The evolution of the old series is far more advanced. The rounded solution cavities imply that the cave was formed by water of elevated temperature. The lack of coarse-grained fluvial deposits, Pleistocene mammal remains and Palaeolithic artefacts prove that the cave was isolated since its inception till Holocene time. The cave originated due to artesian circulation, when the Wawel Horst was covered by imper- meable Miocene clays. A foreland basin with carbonate basement, filled with fine-grained molasse-type deposits seems to be particularly favourable for the development of artesian caves.

15

Evolution of Brestovská Cave based on U-series dating of speleothems

Hercman H., Gradziński M., Bella P.

Geochronometria

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2008

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Vol. 32

1-12

EN

The U-series dating indicates five episodes of flowstone growth in Brestovská Cave, namely: ca. 200 ka, ca. 128-88 ka, ca. 82-65 ka, ca. 64-50 ka, and during the Holocene. The age of flowstones and their spatial distribution within the cave prove that the upper storey of the cave was dewatered before 200 ka. At that time the lower storey also existed and was able to carry the whole water flowing through the cave. It suggests that 200 ka ago the water-table was at similar level as it is at present. Hence, one should accept that the valley bottom was then also at the present level. During at least a part of the MIS 6 the growth of speleothems was possible in the cave. It suggests that the cave was located outside the permafrost zone then. Between 50 ka and Holocene, Brestovská Cave was flooded by invasion waters originating from the melting of the Würm glacier; the water-table was additionally raised due to the blockage of a resurgence by glacifluvial sediments. The flooding event caused the destruction of older deposits, including speleothems, and deposition of fine-grained clastics on the cave walls.

16

Age of black coloured laminae within speleothems from Domica cave and its significance for dating of prehistoric human settlement

Gradziński M., Hercman H., Nowak M., Bella P.

Geochronometria

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2007

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Vol. 28

39-45

EN

The paper deals with the black coloured laminae which occur within speleothems in Domica cave (Slovakia). The laminae are composed of non completely carbonized organic compounds and charcoal particles. The components were formed during combustion of plant material, mainly wood, inside the cave. Thus, they are a by-product of human activity inside the cave. The radiocarbon ages of organic fraction of these laminae fall between 6460 and 6640 cal BP and 7160 and 7330 cal BP. These dates indicate that the origin of the laminae is connected with two episodes of prehistoric occupation of the cave. The first one should be related either to later part of Gemer Linear Pottery or to early Bükk culture populations. The second episode refers to the youngest phase of human occupation in Domica cave reflecting the last period of Bükk populations' existence in the Slovak Karst.

17

Chemistry of cave water in Smocza Jama, city of Kraków, Poland

Motyka J., Gradziński M., Różkowski K., Górny A.

Annales Societatis Geologorum Poloniae

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2005

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Vol. 75, No 2

189--198

EN

The chemical composition of the water in Smocza Jama cave (city of Kraków, Kraków-Wieluń Upland) was studied. The cave is 276 m long and it was developed in the Upper Jurassic limestone. Nineteen water samples were collected between March 1995 and January 1998. The pool water and drip water were sampled. The former water samples represent Ca - Na - HCO3 - SO4 - Cl, while the latter ones SO4 - Ca - Na type. In pool water the concentrations of Cl are higher than in drip water, while in drip water the SO4 predominates. The chemical composition of the studied samples of both the pool and drip waters differs considerably from the composition typical of the limestone cave water. The studied water differs also in its chemical composition from the ground- water of the Kraków-Wieluń Upland. High concentrations of NO3, SO4, Cl, Na, K, and P suggest that the water in Smocza Jama is considerably affected by pollution. The chemical composition of the studied pool water can be the effect of mixing of, at least, two components. The water can: (i) filtrate from the Vistula river, (ii) percolate down from the surface of Wawel Hill, (iii) migrate from the nearby area, where the city centre is located, and (iv) ascend as artesian water from deeper confined aquifer. The former three of the four mentioned water sources may be strongly degraded due to long lasting human occupation of both Wawel Hill and the city centre, as well as pollution of the Vistula river. The high amount of SOS ions reaching 1439 mg/L in drip water results probably from leaching of litter and rubble poured over the cave in the 19th century.

PL

Jaskinia Smocza Jama jest usytuowana w centrum Krakowa, w południowej częoeci Wyżyny Krakowsko-Wieluńskiej (Fig. 1, 2). Powstała ona w wapieniach jury górnej budujących niewielki zrąb otoczony głównie iłami mioceńskimi znajdującymi się w sąsiednich rowach tektonicznych. W jaskini występują jeziorka (Fig. 3); ich powierzchnia położona jest w przybliżeniu na poziomie wód Wisły, która płynie w odległości ok. 50 m od jaskini. Fluktuacje poziomu wody w jaskini nawiązują do zmian poziomu wody w Wiśle (Kleczkowski, 1977). Badane było szesnaście próbek wody pobranych z jeziorek i trzy próbki wody kapiącej ze stropu jaskini (Fig. 3). Wszystkie próbki reprezentowały wody słabo alkaliczne. Mineralizacja ogólna wód z jeziorek była mniejsza niż wody kapiącej. W pierwszym przypadku wynosiła od 779,25 mg/L do 1013,01 mg/L podczas gdy w drugim od 1752 mg/L do 2841,73 mg/L (Tabela 1).

18

In-channel accretionary macroforms in the modern anastomosing system of the upper Narew River, NE Poland

Gradziński R., Baryła J., Doktor M., Gmur D., Gradziński M., Kędzior A., Paszkowski M., Soja R., Zieliński T., Żurek S.

Annales Societatis Geologorum Poloniae

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2003

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Vol. 73, No 1

35-53

EN

Predomination of sandy bedload is typical of the anastomosing channels of the Narew River. Several types of in-channel accretionary macroforms have been found in these channels: side bars, concave-bank bars, plug bars, point bars, linguoid bars, and mid-channel bars. The first three types are relatively rare, point bars occur only exceptionally, while linguoid bars and mid-channel bars are quite common. The bars usually occur in main channels, which are the master routes of sand transport in the whole anastomosing system of the Narew. The lower parts of the bars are built of coarse- and medium-grained sand, similarly to the sediments in the deeper parts of the channels. Fine-grained sand, locally alternating with organic-rich muddy sand, predominates usually in the upper parts; peat with high content of sand is present in the highest parts of some bars. All bars are rapidly colonised and stabilised by plants. It is for this reason and due to the low energy of the river that the bar sediments have a high preservation potential. The development of bars is usually not accompanied by lateral migration of channels. Consequently, sediment accretion in bars is one of the factors leading to gradual narrowing of channels. Deposits of some sand-bars, when preserved in fossil record, may probably be represented by characteristic "wings" in the outer parts of ribbon-like sand bodies.

19

Morphology of Czarna Cave and its significance for the geomorphic evolution of the Kościeliska Valley (Western Tatra Mts)

Gradziński M., Kicińska D.

Annales Societatis Geologorum Poloniae

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2002

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Vol. 72, No 3

255-62

EN

Czarna Cave represents phreatic cave with multiple loops. No cave level developed at the water table was detected. The cave was later modified by invasion vadose waters and breakdown processes. The phreatic paleoflow directions were analyse from the asymmetry of scallops. The paleoflow was directed from the east to the west, that is in a direction of the Kościeliska Valley. Therefore, this valley represented the main discharge zone of the region during the formation of Czarna Cave.

PL

Autorzy wykonali analizę rozmieszczenia przestrzennego korytarzy Jaskini Czarnej. Kierunek paleoeoprzepływów zrekonstruowano na podstawie asymetrii zagłębień wirowych (scallops’, Tabela 1; por. Rudnicki, 1960; Curl, 1966; Lauritzen & Lundberg, 2000 i literatura tam cytowana). Układ korytarzy ciągu głównego Jaskini Czarnej oraz ich poprzeczne przekroje dowodzą, że jaskinia ta rozwijała się jako system wielu, połączonych z sobą pętli freatycznych (Ford & Ewers, 1978; Ford & Williams, 1989; Ford, 2000). Deniwelacja pojdyńczych pętli sięga kilkudziesięciu metrów. Część korytarzy o poziomym rozwinięciu, np. Korytarz Mamutowy i Korytarz Żyrafo wy, stanowiła zapewne korytarze typu obejść lub izolowanych wady cznych rozcięć (bypass, isolated vadose trench’, Ford & Ewers, 1978; Ford & Williams, 1989; Ford, 2000). Niestety późniejsze zmiany morfologii jaskini wywołane przez procesy zawaliskowe uniemożliwiają precyzyjne ustalenie punktów przejścia pomiędzy strefą freatyczną i wadyczną(Fig. 3; por. Palmer, 1987, 2000). Zebrane obserwacje świadczą, że główny ciąg Jaskini Czarnej powstał na zróżnicowanej głębokości poniżej piezometrycznego zwierciadła wód krasowych (Fig. 4, 5). Stanowi on więc jedno genetyczne piętro (cave storey) rozwinięte w warunkach freatycznych (por. Ford, 2000). Nie można więc wyróżniać w jego obrębie tzw. poziomów jaskiniowych (cave levels) odpowiadających dawnemu poziomowi zwierciadła wód i w przybliżeniu dawnemu po-ziomowi bazy erozyjnej. Powyższy pogląd neguje dotychczasowe koncepcje dotyczące rozwoju Jaskini Czarnej (Wójcik, 1966, 1968; Rudnicki, 1967; Grodzicki, 1970, 1991; patrz też Tabela 2), które opierały się w większym lub mniejszym stopniu na teorii Swinnertona (1932). Teoria ta zakłada rozwój jaskiń krasowych jako w przybliżeniu horyzontalnych ciągów powstających w pobliżu zwierciadła wód. Freatyczne ciągi Jaskini Czarnej były już po osuszeniu modyfikowane przez wadyczne przepływy, zapewne o charakterze wód inwazyjnych pochodzących z topnienia pól firnowych lub lodowców plej stoceńskich (por. Głazek etai., 1977, 1979; Głazek 1997). Wody te ukształtowały pionowe studnie i kominy młodsze od głównego ciągu i w wielu miejscach rozcinające go. Spowodowały także lokalne wadyczne modyfikacje starszych freatycznych ciągów (Fig. 6, patrz też Fig. 9). Analiza kierunków paleoprzepływów w Jaskini Czarnej wykonana na podstawie obserwacji zagłębień wirowych w dwunastu miejscach w jaskini wykazała jednoznacznie, że pierwotnie przepływ ten skierowany był ze wschodu ku zachodowi (a dokładnie z północnego wschodu ku południowemu zachodowi) czyli ku Dolinie Kościeliskiej (Fig. 2, 7, 8, 9). Dlatego nieaktualne są dotychczasowe poglądy dotyczące kierunków paleoprzepływów w tej jaskini, wyrażane najbardziej zdecydowanie przez Grodzickiego (1970, 1991). Powyższe obserwacje wskazują, że w czasie aktywnego freatycznego przepływu poprzez główny ciąg Jaskini Czar-nej, czyli w neogenie (por. Nowicki et al., 2000), główna strefa odwodnienia była położona w Dolinie Kościeliskiej w rejonie dzisiejszej Polany Pisanej. Świadczy to, że już wówczas dolina ta była jedną z najniżej wciętych dolin Tatr Zachodnich. Można zatem przyjąć, że Jaskinia Czarna stanowi dawny, nieaktywny odpowiednik dzisiejszego systemu Lodowego Źródła. Prowadziła ona bowiem wodę z masywu Czerwonych Wierchów ku zachodowi, w stronę Doliny Kościeliskiej, tak jak ma to miejsce współcześnie w tym systemie.

20

Jaskinie lawowe - zarys problematyki

Gradziński M., Jach R.

Przegląd Geologiczny

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2001

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Vol. 49 nr 12

1191-1196

PL

Jaskinie rozwinięte w lawach są stosunkowo słabo znane pomimo tego, że są one częstym zjawiskiem w wielu rejonach świata. Większość takich jaskiń to fragmenty tzw. rur lawowych. Powstanie rur lawowych jest związane ze spływami lawy bazaltowej. Najczęściej rury takie są rozwinięte w lawach pahoehoe cechujących się małą lepkością, lecz znane są także z law aa o większej lepkości. Powstanie rur lawowych jest wynikiem różnych procesów. Najczęściej jest efektem rozwoju skorupy ponad płynącym strumieniem lawy. Taka skorupa ostatecznie pokrywa cały potok lawowy. Powstaje ona dzięki gradientowi termicznemu pomiędzy płynącą lawą a atmosferą. Rury lawowe są dobrymi izolatorami cieplnymi i pełnią rolę kanałów dla strumieni lawowych płynących na duże dystanse. Dlatego też powstanie rur lawowych jest bardzo istotnym czynnikiem dla rozwoju rozległych spływów lawowych. Płynąca lawa powiększa rurę lawową na skutek erozji termicznej i mechanicznej. Dzięki temu wewnątrz rur lawowych powstają wcięte meandrujące koryta, lawospady, świetliki i toczeńce lawowe. Inne charakterystyczne elementy rur lawowych jak półki znaczące dawny poziom potoku lawowego, wały przykorytowe, wewnętrzne rury są efektem akrecji lawy wewnątrz rur lawowych. W jaskiniach lawowych występują też różnorodne speleotemy zbudowane z gipsu, węglanu wapnia i opalu.

EN

Caves developed in lavas are not broadly known despite the fact that they are quite a common phenomenon in some parts of the world. Majority of such caves form as lava tubes and they are called lava tube caves. The origin of lava tubes is related to flows of basaltic lava. They are mostly developed in a low-viscous pahoehoe type of basaltic lava, but some caves located in a viscous aa lava are also known. The origin of the lava tubes has been ascribed to various mechanisms. The most frequent seems to be the growth of stationary crust over a flowing lava stream. Finally, this crust completely roofs a lava stream. This is brought about by a contrasting thermal gradient between the flowing lava and the atmosphere. The lava tubes are good heat isolators and they act as long conduits for flowing lava. Thus, they are a very important factor for propagation of lava and the origin of broad lava flows. The flowing lava widens the tube as a result of thermal and mechanical erosion. The above processes form several characteristic features of lava tube interior, e.g. incised meandering channels, lavafalls, skylights, lava balls. Other features, for example, lateral benches, internal levees, tube-in-tube structures, are effects of lava accretion inside the tubes. Various speleothems made of gypsum, calcium carbonate, as well as opal can form in lava tube caves.