Commune: Busko-Zdrój (pow. buski, woj. świętokrzyskie)
Framework element or context represented:
Sequences of marine sediments of Upper Jurassic, Upper Cetaceous and Neogene (Badenian) of Nida basin separated with stratigraphic gaps and discordances.
Primary geological/geomorphological interest:
Stratigraphic sequence with Alpine tectonic gaps and unconformities.
Comparative assessment justification:
The most illustrative outcrop documenting stratigraphic-tectonic evolution of the Nida basin during Alpine cycle (Jurassic-Neogene).
Protection status and accessibility:
Protected as a documentary site (since 1993) – accessible.
Character of site: Abandoned quarry.
Area: 11.19 ha
Altitude: 270-285 m a.s.l.
Lithology: sandstones, conglomerates, breccias, other siliceous rocks, limestones, marls, shales
Discipline: Palaeoenvironment, Stratigraphy of Phanerozoic, Tectonics
Process Age: Quaternary, *all periods
Bedrock Age: Neogene, Cretaceous, Jurassic, *all periods
Description of primary interest:
The sequence exposed in the abandoned quarry comprises the Upper Jurassic limestones and Upper Cretaceous rocks overlain by transgressive facies of Miocene. Two phases of Alpine tectonic movements are perceptible here. The first discontinuity (gap with traces of erosion and low angle discordance) is observed between the Oxfordian limestones and Cenomanian sandstones. The Jurassic is represented with bedded limestones dipping 35º to the north. Thin Cenomanian glauconitic sandstone layer (less than 1 m) contains phosphorite nodules and inoceramian shells. It is overlain by the Turonian limestones grading to thick complex of Turonian and Senonian marls and opokas bearing numerous flynt nodules and horizons. Occurrence of relics of submarine hot water springs are supposed in the Cretaceous rocks. Paleo-surface of the Cretaceous and Jurassic rocks, shaped by marine abrasion, is discordantly covered by Badenian breccia-conglomerate, which is irregularly intercalated with sandy limestone. The breccia is composed of weakly cemented fragments of its substratum (limestones, flints and marls) - boulders, rubble, pebbles, often with animal borings (sponges, lamellibranchs, polychaetes, gastropods) and incrustations (bryozoans, polychaetes, lithothamnia). Biogenic material (foraminifera, algae) occurs also in matrix of the breccia. The main body of breccia represents allochtonous sediment of littoral fore-cliff depression. They are overlain by biodetrital and lithothamnian (algal) limestones containing also other fossils: foraminifers, gastropods, lamellibranchs (pelecypods), echinoids, and teeth of fishes. Miocene rocks slightly dip to the north (the discordance angle – ca. 20º).
Literature:
JURKIEWICZ W., MORAWIECKI A. 1956–On phosphorite-bearing Cenomanian conglomerate from Mt Zajęcza Góra near Busko (English sum.). Arch. Miner. 19 (1955), 2: 181-200. MAŁECKI J. 1966–Miocene Bryozoa from the borings of lithopags of Skotniki near Busko, Central Poland (English sum.). Roczn. Pol. Tow. Geol. 36, 4. 481-495. MIGASZEWSKI Z.M., HAŁAS S., DURAKIEWICZ T. 1996–The age and origin of the calcite mineralization in the Holy Cross Mts based on lithologic-petrographic and isotopic evidence (English sum.). Przegl. Geol. 44: 275-281. MIGASZEWSKI Z.M., SIUDA T., WALASZCZYK I. 1987–Upper Cretaceous pyroclastic and hydrothermal formations of the southwestern borderland of the Świętokrzyskie Mts (Busko-Pińczów area). (English sum.). Przegl. Geol. 35, 8-9: 425-431. RADWAŃSKI A. 1965–Additional notes on Miocene littoral structures of Southern Poland. Bull. Acad. Pol. Sc., ser. Sc. Geol.-Geogr. 13, 2: 167-173. RADWAŃSKI A. 1967–Pitting processes in clastic and oolitic sediments (English sum.) Roczn. Pol. Tow. Geol. 35, 2: 179-210. RADWAŃSKI A. 1969–Lower Tortonian transgression onto the southern slopes of the Holy Cross Mts (English sum.). Acta Geol. Pol., 19: 1-164. URBAN J., WRÓBLEWSKI T. 1999–Representative geosites of the Góry Świętokrzyskie (Holy Cross Mts.) and the Nida Basin, Central Poland. Pol. Geol. Inst., Special Papers, 2: 61-70. WALASZCZYK I. 1992–Turonian through Santonian deposits of the Central Polish Uplands, their facies development, inoceramid paleontology and stratigraphy. Acta Geol. Pol., 42: 1-122.