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A putative Tournaisian and Visean volcanic-sedimentary succession in the Lublin Basin, SE Poland: depositional processes, petrological characteristics and sequence stratigraphy

Waksmundzka Maria I., Kozłowska Aleksandra, Pańczyk Magdalena

Acta Geologica Polonica

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2021

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Vol. 71, no. 3

305--344

EN

The aim of this study was to establish the stratigraphic extent of a putative Tournaisian Stage within the Carboniferous succession in the Lublin Basin. The oldest part of the succession, known as the Huczwa Formation and comprising depositional sequences 1-4, was investigated based on lithofacies analysis, sequence stratigraphy and petrographic studies. The article provides descriptions of depositional sequences, parasequences (cyclothems) and lithofacies that were formed in a range of environments (elements of depositional architecture) and as a result of volcanic processes - lava and pyroclastic eruptions and chemical weathering of their products. Correlation of the sequence stratigraphy to the West European and global Carboniferous chronostratigraphic divisions, as well as to the Khoriv suite in the Lviv-Volyn Basin in adjacent Ukraine, indicates a putative late Tournaisian age for sequence 1, and a late Visean age for sequences 2-4. There is a stratigraphic gap between sequences 1 and 2, spanning probably the uppermost Tournaisian and the lower and middle Visean. The upper Tournaisian is represented by the FRST-LST deposits of sequence 1, comprising mainly volcaniclastic conglomerates and sandstones developed in braided-river channels and incised valleys with hyperconcentrated flow processes. These deposits are represented by polymictic paraconglomerate and lithic/sublithic/subarkose arenites or sublithic wackes, and contain predominantly grains of acidic and alkaline volcanic and igneous rocks. This material probably came from the Łuków-Wisznice Elevation and the Volynian Polesia region, located to the NE and E of the Lublin Basin. In the uppermost part of sequence 1, volcanic rocks and tuffs appear which developed during the activity of at least three volcanic cones in the Lublin Basin. The volcanoes were the source of alkaline lavas in the central and SW areas of the basin, and of acidic lavas in the SE area, previously undescribed. The Visean sequences 2-4 consist of the FRST-LST sediments deposited within incised valleys. The TST and HST deposits accumulated mainly in a shallow ramp-type carbonate shelf, shallow clayey shelf and deltaic environments.

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Braided-river and hyperconcentrated-flow deposits from the Carboniferous of the Lublin Basin (SE Poland) - a sedimentological study of core data

Waksmundzka Maria I.

Geologos

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2012

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Vol. 18, No. 3

135--161

EN

Fining-upwards cyclothems found in five boreholes in the Carboniferous (Lower Bashkirian) of the Lublin Basin were analysed sedimentologically. It was established that the cyclothems represent fluvial deposits, and the lithofacies were grouped into lithofacies associations. Most lithofacies associations represent three types of sand-bed braided rivers: (1) high-energy, (2) deep and (3) distal sheetflood-affected. Other associations represent hyperconcentrated flows. Both coarse-grained (type I) and fine-grained (types IIa and IIb) occur among the fining-upward cyclothems. The formation of most thick cyclothems was related mainly to allocyclic factors, i.e. a decrease in the river’s gradient. The thickest fining-upward cyclothems are characteristic of hyperconcentrated flows and braided-river channels. The aggradation ratios were commonly high. During the early Namurian C and early Westphalian A (Early Bashkirian), the eastern part of the Lublin Basin was located close to the source area. The sedimentary succession developed due to a transition from high-energy braided-rivers and hyperconcentrated flows to lower-energy braided rivers, controlled by a rise of the regional base level.

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Sequence stratigraphy of Carboniferous paralic deposits in the Lublin Basin (SE Poland)

Waksmundzka M.

Acta Geologica Polonica

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2010

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Vol. 60, no. 4

557-597

EN

Based on lithofacies analysis of clastic, clay and carbonate rocks, wireline logs and sequence stratigraphy, sixteen depositional sequences have been distinguished in the paralic Carboniferous succession of the Lublin Basin from the Visean to the base of Westphalian B. The facies evolution and depositional architecture of the deposits belonging to three types of depositional systems tracts, i.e. lowstand (LST), transgressive (TST) and highstand (HST) have been reconstructed. The sequences are bounded by type 1 basal unconformities formed during subaerial erosion following relative sea-level fall and lowstand. This erosion, that in some cases reached down to the LST deposits of the underlying sequences, mainly affected the HST deposits. Relative sea-level rise controlling the base level of the rivers during lowstand was the basic factor influencing facies development, cyclicity and thickness of fluvial deposits, as well as the vertical and lateral transformation of rivers in theparalic Carboniferous succession. Vertical transition of high- to low-energy fluvial environments can be observed within the LST. The LST deposits typically occur in incised shelf valleys and in non-incised fluvial systems. Within the LST of sequences 2 and 4 to 10 commonly occur medium and large systems of simple incised valleys that developed in a coastal-plain system. The LST of sequences 11 to 15 comprises large systems of compound incised valleys that developed in a piedmont system. Relative sealevel rise in the late lowstand, sea-level oscillations during transgression and highstand and the volume of sediment supply were the main factors influencing facies development, cyclicity, thickness and lateral distribution of the deltaic deposits, shallow-shelf shales and limestones. Within the TST commonly occur coarsening-upward and non-gradational cyclothems that correspond to parasequences and were formed in the distal parts of the inner-shelf delta lobes. In the HST, the most commontypes are coarsening-upward cyclothems developed during the progradation of innershelf delta lobes and small lake deltas, as well as non-gradational cyclothems formed in lakes on a delta plain without influence of delta lobes. The transgression of sequence 7 probably had the widest extent of all the sequences in the paralic Carboniferous succession of the Lublin Basin. It was presumably much wider to the N, NE and NW than the presently accepted boundaries of the basin. Based on analysis of three curves of relative sea-level changes in the paralic Carboniferous succession of the Lublin Basin and the transgressive-regressive curve for the Carboniferous of Western Europe, the sequences distinguished have been correlated with the chronostratigraphic scheme for the Carboniferous System. The diachronous commencement of sedimentation has been confirmed and evaluated. The lack of deposits of sequence 5 in the eastern part of the basin suggests the presence of a stratigraphicgap encompassing the upper Brigantian. The position and range of stratigraphic gaps present elsewhere in the basin has also been indicated. In the north-westernmost and easternmost parts of the study area the gap has the widest range, encompassing the upper Arnsbergian to lower Marsdenian strata. The mid-Carboniferous boundary between the Mississippian and Pennsylvanian has been located at the base of sequence 8.

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History of sedimentation of the Nida Gypsum deposits (Middle Miocene, Carpathian Foredeep, southern Poland)

Bąbel M.

Kwartalnik Geologiczny

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1999

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Vol. 43, Nr 4

429-447

EN

The Nida Gypsum deposits are the best exposed in Poland part of the Middle Miocene (Badenian) evaporites of the Carpathian foreland basin. These deposits record various shallow water (<< 5 m) evaporative environments. The facies sequence in the lower part of evaporites reflects shallowing (up to emersion) and than deepening accompanied with salinity rise up to halite precipitation. The salinity rise was arrested by refreshment promoting subaqueous dissolution of sodium chloride. This event was followed by the second large salinity rise and then final dilution of brine which finished evaporative sedimentation. The described two saline cyclothems are recognizable over large area of Carpathian foreland basin.

PL

Na podstawie rozprzestrzenienia 5 wyróżnionych pierwotnych facji (M. Bąbel, 1999b), reprezentowanych przez gipsy szklicowe, rumosze kryształów gipsu, gipsy trawiaste, szablaste i mikrokrystaliczne, oraz szczegółowe interpretacje środowisk sedymentacji ich 12 subfacji (tab. l; M. Bąbel, 1999b), odtworzono historię sedymentacji środkowomioceńskich gipsów Ponidzia. Osady te tworzyły się w płytkim (0-5 m) basenie ewaporacyjnym. Stałe pionowe następstwo facji w dolnej części profilu: gipsy szklicowe-trawiaste-szablaste-mikrokrystaliczne, jest wynikiem spłycenia (a lokalnie wynurzenia prowadzącego do powstania rumoszy kryształów pokrywających gipsy szklicowe) i następującego po nim pogłębienia. Zmiany głębokości były stowarzyszone ze wzrostem zasolenia aż do wytrącenia halitu w gipsach mikrokrystalicznych. Wzrost zasolenia został przerwany rozcieńczeniem solanek, które wywołało rozpuszczenie wcześniej osadzonego halitu. Ponowny wzrost zasolenia wyraził się powtórzeniem sekwencji facji: gipsy trawiaste-szablaste-amikrokrystaliczne w górnej części profilu. Dolne ogniwa tej sekwencji mają zredukowaną miąższność i są obecne wyłącznie na północny badanego terenu. Wyróżnione dwa cykloteny solne można rozpoznać na znacznym obszarze zapadliska przedkarpackiego również na Ukrainie.