Biostratigraphy and depositional anatomy of a large olistostrome in the Eocene Hieroglyphic Formation of the Silesian Nappe, Polish Outer Carpathians

The study focuses on a large olistostrome unit (~200 m thick and 4 km in strike-parallel extent) embedded in the Mid-Eocene shaly Hieroglyphic Formation of the Silesian Nappe, exposed in the Rożnów Lake area. Foraminifer biostratigraphy and petrographic comparisons are used to identify the provenance of olistoliths. The olistostrome is tripartite with respect of its olistolith composition. The lower part of the olistostrome abounds in olistoliths of sandstones derived from the Early Eocene turbiditic Ciężkowice Formation, whereas the middle part is dominated by olistoliths of Early Eocene bathyal mudshales. The upper part contains olistoliths of Middle Eocene turbiditic “banded sandstones”, known from the Hieroglyphic Formation and deposited in the bathyal zone above the CCD. The bathyal provenance of the olistostrome contrasts with the abyssal origin of the hosting green shales. The olistostrome unit is inferred to be composite, emplaced in the earliest Bartonian or at the Lutetian/ Bartonian transition by a series of at least three large debris flows that closely followed one another. Biostratigra- phical data and slump-fold vergence suggest resedimentation from the bathyal northern slope of the Silesian Cordillera that bounded the abyssal Silesian Basin to the south. Northward movement of the thrust-formed cordillera must have warped up the base-of-slope deposits of the Ciężkowice Formation, causing their gravita- tional collapse. This event destabilized the former lower-slope muddy deposits, resulting in a second phase of resedimentation by retrogressive slumping, which led to the collapse of mid-slope sandy turbidites. The slope failures involved contemporaneous Mid-Eocene sediment with an admixture of foraminifers derived from the upper slope or shelf margin and with exotic bedrock debris shed from the eroded cordillera crest. The catastrophic multi-phase emplacement of the olistostrome marked the last major thrusting pulse of the second (Late Cretaceous–Late Eocene) stage of tectonic evolution of the Outer Carpathian accretionary prism

Stratigraphy and geological structure of the Magura Nappe in the south-western part of the Gorce Mountains, Outer Carpathians, Poland

The south-western part of the Gorce Mts (Outer Carpathians) is composed of flysch deposits of the Krynica and Bystrica subunits of the Magura Nappe. The Krynica Subunit includes the Late Cretaceous–Paleocene Ropianka Fm, the Early Eocene Beloveža Fm, the Early Eocene–Oligocene Magura Fm and the Oligocene–Early Miocene Malcov Fm, while the Bystrica Subunit includes the Middle Eocene–?Oligocene Magura Fm, represented mainly by the thick-bedded Magura Sandstone. Thin- and medium-bedded sandstone-shale turbidites predominate in the other formations. The lithostratigraphic units are dated on the basis of foraminifers. The studied deposits accumulated in the southern part of the Magura Basin. Their detrital material was derived from a ridge, bounding the basin in the south. In the study area, the Krynica Subunit overthrusts the Bystrica Subunit. The studied deposits are folded, thrust and cut by numerous faults. The Turbacz Thrust Sheet and the newly identified Kudłoń Thrust Sheet were distinguished in the Krynica Subunit. Faults of different lengths and throws are transverse or oblique. Some of them form complex dislocation zones with lengths of up to several km. In general, the high-resolution digital elevation model DEM contributed significantly to progress in the geological and geomorphological research

An olistolith interpretation for the Paleocene Szydłowiec sandstones in the stratotype area (Outer Carpathians, Poland)

The thick-bedded complex of the Szydłowiec sandstones belongs to the lithological succession of the Subsilesian sedimentary area in the Polish Outer Carpathians. These sandstones contain abundant carbonate biogenic fragments, redeposited from shallower parts of the basin. Their Paleocene age is documented by autochthonous assemblages of agglutinated foraminifera as well as by the microflora occurring within the limestone clasts. The Szydłowiec sandstones in its type locality (locus typicus) at Szydłowiec in the vicinity of Wadowice forms, together with the Gorzeń sandstones, an isolated block surrounded by deformed flysch of the Oligocene-Miocene Krosno Formation, and contains shale clasts of older deposits. According to our results this block represents an olistolith which slided into the Skole part of the Menilite-Krosno basin during the Late Oligocene/Early Miocene deformational phase linked to the development of the Carpathian accretionary prism

Biostratigraphic and paleoecologic interpretation of the agglutinated foraminifera assemblages of the Paleocene-Middle Eocene deposits of the Magura Nappe in the area of Sucha Beskidzka (Outer Carpathians)

Analiza otwornic aglutynujących z paleoceńsko-środkowoeoceńskich osadów płaszczowiny magurskiej, ze strefy raczańskiej północnej, była przedmiotem badań, na podstawie których ustalono, że wyższa część warstw inoęeramowych, pstre lupki dolne z Łabowej (fm) oraz dolny piaskowiec ciężkowicki są wieku paleocenskiego, pstre łupki środkowe (fm) powstały we wczesnym eocenie, a pstre łupki górne (fm) w eocenie środkowym. Analiza cech ilościowych i jakościowych według modelu morfogrup (Jones ci Charnock, 1985) pozwoliła na określenie warunków paleoekologicznych panujących przy dnie zbiornika magurskiego, w rozpatrywanym interwale czasowym. W późnym paleocenie i w eocenie środkowym przypowierzchniowa część osadu była gorzej natleniona oraz większa była produktywność wód, w stosunku do warunków panujących we wczesnym eocenie.Agglutinated foraminifera from the Inoceramian beds, variegated shales of the Łabowa Shale Fm., Ciężkowice Sandstone and the Hieroglyphic beds of the northern Raca Subunit (Magura Nappe) were the main subject of these studies. The age determinations based on the foraminiferal assemblages indicate that: the upper part of the Inoceramian beds, lower variegated shales and the lower Ciężkowice Sandstone are of the Paleocene age; middle part of the variegated shales (Łabowa Sh. Fm.) is of the Early Eocene age and the upper variegated shales represent the Middle Eocene. The morphogroup analysis points that during the Late Paleocene and the Middle Eocene it was relatively high organic flux and insufficient oxygenation at the bottom of the basin whereas during Early Eocene time oxygenation was better and surface productivity lower

The Eocene Hieroglyphic beds and Green shales in the Rożnów Lake area (Silesian Nappe, Outer Carpathians) - facies development and biostratigraphy

In the lithostratigraphic section of a sedimentary sequence of the Silesian Nappe in the area of Rożnów Lake, the strata that occur above the Ciężkowice sandstone and below the Globigerina marls are represented by a relatively thin unit informally named the Hieroglyphic beds and a succeeding thick complex of so-called Green shales. The Hieroglyphic beds, deposited over a short time interval during the Lutetian time (Reticulophragmium amplectens zone), are followed by the Green shales that were deposited from the Lutetian to the Priabonian (Reticulophrgamium amplectens, Ammodisus latus, Reticulophragmium rotundidorstum zones). This work describes the foraminiferal assemblages, on the basis of which, the age of the Green shales was established that in the area of Rożnów Lake. Deposition of the Green shale unit started in the Lutetian, while in other regions of the Silesian Basin it is documented from the Priabonian. The upper boundary of the Green shales is isochronous and defined by the base of the calcareous horizon of a specific type of marls known as the Globigerina marls

Paleocene sedimentary record of ridge geodynamics in Outer Carpathian basins (Subsilesian Unit)

The stratigraphic position of the Goryczkowiec Sandstone reflects the Paleocene ridge geodynamics in the Outer Carpathian basins. The Goryczkowiec Sandstone was deposited on the slope of a ridge, known as the Subsilesian Sedimentary Area that originated during reorganization of the Outer Carpathian realm. A Paleocene age of this sand- stone, documented clearly by autochthonous foraminiferal and algal assemblages indicates the time of the final forma- tion of the Subsilesian Ridge. Abundant calcareous material of biogenic origin was transported by turbidity currents into deeper zones. This material includes fragments of carbonate buildups represented by algae, bryozoans and other organisms growing in the shallower part of the ridge. The Goryczkowiec Sandstone, previously known as the Szydłowiec Sandstone, is here redefined as a new lithostratigraphic unit within the Subsilesian Sedimentary Area in the marginal Outer Carpathians in Poland. The new name clarifies the ambivalence in the lithostratigraphic nomenclature

Type locality of the Mutne Sandstone Member of the Jaworzynka Formation, Western Outer Carpathians, Poland

The Mutne Sandstone Member occurs within the Jaworzynka Formation of the Magura Nappe deposits, typical for the western marginal Siary subunit. In the area north of Jeleśnia it is represented by the thick sandstone complex. Typical and complete profile of this division is located in Mutne village next to Jeleśnia, on the slope of Janikowa Grapa Mt. This locality represents the type section for the Mutne Sandstone Member, while three others: Jaworzynka, Rychwałdek and Kuków-Rzyczki serve as reference sections. The age of the Mutne Sandstone Member was determined as Maastrichtian-Palaeocene; but only Maastrichtian is documented by foraminiferal assemblages. The Palaeocene age comes however from the superposition of this lithosom within the Magura Nappe profile. The Campanian/Maastrichtian-Palaeocene complex of Siary Subunit deposits provides the perfect example for application of supersequences to the Western Flysch Carpathian basin. It fits the Upper Zuni IV supersequence and global time slice. The Mutne type locality is also a prime geotourist attraction and object of inanimated nature proposed for protection

Geodynamics and paleogeography of the Silesian Ridge in the Outer Carpathians

The complex Mesozoic and Cenozoic tectonics of the Outer Carpathians produced series of ridges separating deep water basins.The Silesian Ridge existed since from Jurassic till Oligocene times. Today this ridge is destroyed totally and is known only from olistoliths and exotic pebbles in the Outer Carpathian flysch. It separated the proto-Silesian Basin from the Alpine Tethysduring Jurassic-Early Cretaceous times.The carbonate platform was initially developed on this submarine ridge providing excellent conditions for organic life, represented by calcareous algae, sponges, corals, bryozans, brachiopods, bivalves, ammonites and crinoids. The Late Cretaceous uplift of the Silesian Ridge produced a tremendous amount of clastic material.The submarine fragments of the Silesian Ridge provided favorable conditions for development of shallow banks with the carbonate platform sedimentation during Paleocene-Eocene times. Shallow water, probably narrow shelf locally was dominated by Paleocene and Eocene reefs built of red algae together withbryozoans, brachiopods, sometimes corals and foraminifers. Patchily distribution of these faunas is confirmed by local occurrence of redeposited organic limestones within siliciclastic material. The accretionary prism of Outer Carpathians reached the Silesian Ridge during latest Eocene-Early Miocene. The uplifted part of the nappes produced big olistoliths, which glided down into the adjacent, more distal basins. Finally, the ridge collapsed as a result of the lithosphere flexure in the southern part of the Silesian basin and was destroyed during Neogene times

Paleogene of the Magura Nappe adjacent to the Pieniny Klippen Belt between Szczawnica and Krościenko (Outer Carpathians, Poland)

The present authors investigated the Paleogene deposits of the internal zone of the Magura Basin known as Krynica Subunit or Krynica Zone in Poland. These deposits crop out in the peri-Pieniny zone, in area between Szczawnica and Krościenko. The oldest flysch deposits belong to the Paleocene – Lower Eocene Szczawnica Formation. This formation is covered by the thin-bedded turbidites of the Eocene Zarzecze Formation locally with intercalations of the thick-bedded sandstones of the Krynica Member and Łącko-type marls.  The youngest rocks in this area belong to the Eocene-Oligocene Magura Formation.  The Zarzecze Formation occupies a big part of the Krynica zone of the Magura Nappe border structure. Some deposits previously distinguished as the Szczawnica Formation were transferred to the Zarzecze Formation. The foraminiferal assemblages confirm the Eocene age of these deposits