Úrkút Manganese Ore Formation

The Úrkút Manganese Ore Formation is a Jurassic geologic formation in Hungary. It covers the Early Toarcian stage of the Early Jurassic, and it is one of the main regional units linked to the Toarcian Anoxic Events.[3][4] Different fossils heve been recovered on the locattions, including marine life such as Ammonites[5] Fish[6] and terrestrial fossils, such as Palynomorphs[7] and fossil wood.[8] Úrkút (17´38'E and 47´05'N) and Eplény (17´55'E and 47´12'N) are the main deposits of the Formation.[2] Are related to the Bakony Range, an ancient massif that was uplifted gradually and exposed to a long period of erosion, where the deposits of Úrkút appear to be a basin inclined gently to the north, while the highest point to the south is the basalt mass of Kab Mountain. Eplény region consists of a broad N-S trending open valley between fiat-topped, small hills.[2]

Úrkút Manganese Ore Formation Stratigraphic range: Toarcian ~182 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓ [1]
Ancient karst formation in an abandoned manganite quarry in Úrkút
Type	Geological formation
Unit of	Úrkút Basin
Underlies	Épleny Limestone Formation
Overlies	Isztimér Formation
Thickness	15 m (49 ft)
Lithology
Primary	Manganese
Other	Rhodochrosite
Location
Region	Central Mountains of Transdanubia
Country	Hungary
Extent	~12 km (7.5 mi) by 4–6 km (2.5–3.7 mi)
Type section
Named for	Úrkút
Named by	Drubina-Szabo[2]
Year defined	1959
Úrkút Manganese Ore Formation (Hungary)

Geology

The Urkut Area is part of the Bakony Tectonic Block, with the abundant presence of faults dividing the region into several segments.[2] The terrain where the Manganese Ore is developed is characterised by a high fracturation, where the Jurassic beds and shale lent themselves readily to deformation, with minor folds, faults and shear zones.[9] During the geological evolution of the Bakony range a series of principal fractures were active repeatedly, yielding to vertical as well as horizontal forces that ultimately produced the structural make-up controlling the present topographic configuration of the area.[9] The Jurassic sediments, along the other Mesozoic aged strata were deposited in a branch of a Geosyncline, connected with the Alpine coeval biota.[2] On the Triassic-Jurassic boundary Kimmerian movements take place, as evidenced by the change observed on the texture of the local Calcareous sediments, interpreted as a gradual rising of the sea bottom.[9] To the end of the Lower Jurassic, on the Toarcian, there are several records of another series of pulses from Kimmerian movements, that resulted in partial emergence, which dates the beginning of Karst development on the Csirda Mountain. However, marine sedimentation continued over most of the region and the sea became more widespread.[2] On this time a global sea transgression occur, where on the Úrkút basin shallow-water sediments accumulated near the margins, and with progressive deepening of the sea bottom until the end of late Liassic time, sediments of correspondingly deeper water were deposited.[2] Due to a cut-off of water circulation there were a series of changes on the local development of the basin, which led to the accumulation of the manganese minerals.[2]

The Éplény Area shows a structure and geological development with minor differences from those of Úrkút, being considered overall identical. However, it suffered minor deformation during the late Kimmerian movements, and instead of the Austrian movements, the Subhercynian and Laramide movements produced important structures. After the Pyrenean and Savian movements, the Éplény area started to sink slowly and to receive marine sediments, emerging later on the Middle Miocene.[2] The manganese ore group of beds appears in an absolutely different way according to evolution in Eplény, where while in Úrkút 4 beds can be divided, in Eplény, the 3 beds appear usually with sharp boundary, in reduced thickness.[10]

Stratigraphy

Local Manganese Mine

The oldest formations on the Úrkút basin are referred to the Upper Triassic Dolomite range and the Dachstein Limestone of Raetian age. After the deposition of the Traissic rocks a series of Jurassic strata successions have overlain the older deposits, with its lowermost contact found on the uppermost strata of the own Dachstein Limestone, developing a lower Liassic sequence that is a white, yellowish-gray or pink, dense Limestone resembling that of the Dachstein.[2] Over it, there is a series of younger liassic strata and a Crinoid-Brachiopod and Rhynchonellatan bearing reddish Limestone, that resembles the Sinemurian Hierlatz Limestone of the Csárda Mountain, that is the last unit under the coeval Manganese deposits from there.[11] Late Pliensbachian strata is composed by nodular and cherty red limestone with abundant ammonites and brachiopods, that belong to the Isztimér Formation.[12] On the uppermost Pliensbachian strata there is a series of beds that consists of greenish-gray limestone and marl, which also contain crinoids and brachiopods, being the last unit under the Manganese Ore.[2] The Upper Liassic (Toarcian) sequence is composed mostly by the Úrkút Manganese and the Éplény Limestone (Late Toarcian-Aalenian), and starts with thick-bedded, gray, Radiolaria-bearing, argillaceous marl containing several intercalations of manganese carbonate, or rarely, manganese oxides, with the top of the sequence being a brown to purple nodular Limestone with light green spots.[2] Middle Jurassic overlaying these deposits, being mostly a series of cherty Marlstone containing the genus Posidonomya and several types of Radiolaria.[11] The Late Jurassic strata is vanished locally, with the Cretaceous sedimentation starting with several continental beds with Bauxite and accompanying Laterites.[2] Finally, on the Tertiary, the Lower Eocene continental clay and bauxite are overlain by gray carbonaceous clay and sandstone, with the and Jurassic beds and manganiferous beds eroded.[2]

Lithology

Manganese ores are the main lithologic component of the formation, related with depth Volcanic-Hydrothermal conditions

The Manganese Ore is the main component of the formation, and it's distinctive characteristic element.[13] The Úrkút Manganese ores occur on marine sedimentary rocks composed mainly of bioclastic Limestone, radiolarian Clay Marlstone, and dark-gray to Black Shale.[14] The Origin of the Local Manganese Ores based on the presence of siliceous manganese ores and antauthigenic Silica points to the volcanogenic-sedimentary origin of this Mn-ore deposits[15] Manganese nodules are widely distributed in the area in Jurassic rocks, mainly on the Lower Jurassic, but younger nodules also occur.[13] The Black Shale with Mn-carbonate get its maximum deposition on the Toarcian, concretely during the Tenuicostatum–Falciferum Ammonite zones in the coeval Sachrang Formation, Strubberg Formation and Allgäu Formation in the Northern Calcareous Alps and the Eastern Alps (Austria, Germany and Switzerland), while Úrkút and related deposits were the regional equivalent in the Transdanubian Range.[13] There are other deposits with Shale and associated Mn particles on contemporaneous oxic deposits occur that formed under similar environmental conditions.[16] The Úrkút Manganese deposit has been investigated geologically, mineralogically and chemically.[17] It has several properties, including very fine grain size (~ 1 μm), an enrichment of metals over a geologically very short time (-500 thousand years).[17] Both Metals and the Manganese have been related with local hydrothermal vent systems, where the metal enrichment was a result of microbial activity.[18] There are at least three types of Manganese deposits that occur close in proximity. The first, those with cherty Fe–Mn-oxide ore, developed on the margins of the much larger carbonate ore body, whose origin has been related with proximal fracture systems, being composed by varicolored metalliferous Claystone.[19] Other type includes the so-called Csárda-hill, where it is very cherty and iron-rich, and is suggested as originated from a low-temperature fluid flow along an associated fracture zone.[20] This deposit is associated with sedimentary dykes, filled with red Lime-Mudstone, varicoloured Claystone, carbonate debris, or Mn oxides.[20] The last type is the Black Shale-hosted Mn-carbonate, considered a distal ore-forming environment, where the Mn-carbonate proto-ore sediment accumulated.[20] A hydrothermal/exhalative source of metals may have contributed to the formation of the deposits of Black Shale.[21]

This Black Shale level is composed at the base with greenish, organic-rich, pyritiferous clayey marlstone, with several enrichments such as sulfides and barite.[14] Pyrite concretions and thin layers of phosphate and chert are found in the Shale and the lower Limestone.[22] Phosphorus is present as Calciumphosphate, where the latter may be present not only as the component of the local apatite, and related with the P2Os content changes.[22] Although the mean P content of the manganese oxide ore deposits of Eplény and Úrkút is generally less than 1,00 %, being mostly hydroxy-carbonate-Apatite, with some samples more similar to Francolite, while on the Eplény manganese ore deposit is found Dahllite.[23]

There is a rhodochrosite ore, composed of laminated gray, green, brown, and black sections, and is associated with a diagenetic origin.[24] Rhodochrosite concretions with fish and plant fossils are common on the strata, composed by Mn-bearing Calcite with traces of hydroxyl-apatite, kutnohorite, smectite, quartz, feldspar, barite, pyrite, and quartz-cristobalite.[24] Mineralized sections do not contain fossils or traces of benthic fauna, and contain only rarely fish remnants, planktonic organisms as well as silicified, manganized, or coalified plant fragments.[25]

Celadonite and smectite, especially the first, had particular importance for understanding the genesis of the Úrkút manganese ore.[26] Celadonite and nontronite indicate paleo-oxygen level variations in the environment. There are well-crystallised celadonite occurrences that was formed by primary precipitation, differing from the known celadonite occurrences in that it is not found in direct association with submarine basic volcanic rocks, although being any evidence for volcanic contribution to the local ore genesis.[27] The Smectite is also found on the lower Pliensbachian Limestone. Nearly every Sample on Úrkút contains interstratified Illite/smectite.[28]

Local silica is related with the quartz crystallinity of the white tripoli, where based on the dissolution of the carbonate portion of the siliceous Isztimér Limestone Quartz was formed by low-temperature, diagenetic processes.[29] Finally, there were found a series of rare earth elements on the ore, adsorption from sea water, but terrigenous source also displaying a positive Ce anomaly is involved.[30]

The Rn220 and Rn222 concentration in the Úrkút Manganese Formation is anomalously high, and it causes health risk for the attendants of the Úrkút Manganese Mine, which is considered to be related to active fossil Biomat (bacterial action) which leads local minerals to adsorb different atoms or ions, whether they are radiogenic or not.[31]

Paleoenvironment

Black Shale is present worldwide in the lower Toarcian, linked to the anoxic events that took place, in Úrkút locally related with deposits of Manganese Ore.[32] Being part of the Transdanubian Range, the Úrkút Manganese Ore was linked to the environmental evolution of the southern passive margin of the rifting Tethys Ocean.[9] After Hettangian drowning and Sinemurian-Pliensbachian extensional tectonics and subsidence, along with pelagic sedimentation and submarine topography, a pronounced horst developed over the local sea, with a depth on the Pliensbachian-Toarcian Basin of 600 m.[33] The environment of the Formation was linked to 2 settings: a series o pelagic basind, including the Zala Basin and the own Úrkút and Eplieny Basins, related to open marine conditions where bioturbation is scarce, but there is a great amount of planktonic organisms, associated with a suboxic to anoxic conditions.[32] Radiolarians, sponge spirucles, crinoid ossicles, bivalves, gastropods, ammonites and fish were recovered as the main local biota, deposited on a 20–40 m basinal ore sequence.[32] The Other deposits come from the near emerged lands, that include the Gerecse Hills, Vértes Hills and the Bakony Hills, whose biota has been recovered on the formation by palynological analysis and fossil wood.[34]

More recent studies support the lack of any igneous event during Pliensbachian and Toarcian times in the Úrkút Basin.[28] The Smectite formation lacks igneous rocks, tuffs, or volcanic glasses.[28] Although, it can be due to changes in the fluctuation on the basin.[28] Observed Mn veins and their above-proposed formation mechanism do not eliminate completely the possibility of tectonically formed Neptunian dikes elsewhere in the basin, which could well fit in the local, general tectonic environment observed, for instance in Eplény.[35]

In this setting volcanism was the main local event, where eroded near basaltic sequences provided a metallic source for the ore, being channeled by suboxic waters to the Úrkút Basin.[32] The local tectonic activity created fractures and deep faults and there was a development of endogenic thermal effects, such as degassing and the release of solutions, along with the mixing of syngenetic ash falls that deposited Fe into the carbonate rocks.[36] The fine Volcanic material was altered on the Marine sediments. The local hydrothermal emanations in the deep fault zones, where bacterial activity caused the precipitation of large amounts of metal ions in the form of very fine-grained oxyhydroxides. Meanwhile, the accumulation of dead bacteria created a mass of very reactive organic matter. Under aerobic conditions, the action of the microbial oxidation led to the local accumulation of Mn oxides that ended being Ca-rhodochrosite, and supported Celadonite formation by mixing of geological fluids with seawater. It has been calculated 563 years for the duration of ore local formation based on an estimated 3 weeks for a microbial population growth cycle.[37]

The local manganese ore is, in reality, a Mn-ore series of stromatolite with a volcanic tuff component, that was later transformed by diagenetic processes.[36] The modern analog of this environment of the Úrkút Manganese Ore basinal deposits would be flourishing Prokaryotic bacteria colonies located in submarine vent systems, normally related with remnants of proto-rifts or failed rift systems on continental crust in a submarine environment. The local environments are interpreted as hydrothermal vent systems of cooler temperatures.[36]

Fossils

Bivalves

Bivalvia
Genus	Species	Material	Location	Notes	Images
Solemya[38]	Solemya bollensis Solemya voltzi	Shells	Úrkút quarry.	A Clam, type member of the family Solemyidae inside Solemyida. Benthic fauna found in the black slate.
Pseudomytiloides[38]	Pseudomytiloides dubius	Shells	Úrkút quarry.	A Clam, member of the family Inoceramidae inside Myalinida. Mistaken for other related genera on the deposit, it is among the most abundant local clams. Found associated with large Fe deposition.

Brachiopoda

The dominant group are the Terebratulids, while Strophomenids play a significant role.[39] While the Brachiopods and Gastropods are more abundant on the underlying Hiertlaz Formation, but also continuous on the Úrkút and Épleny quarries.[39] In the very rich fauna of the local seamount slope the orders Terebratulida and Rhynchonellida play an equally important role, but the basin areas are characterized by a low-diversity fauna dominated by large terebratulids.[39]

Brachiopoda
Genus	Species	Material	Location	Notes	Images
Linguithyris[40]	Linguithyris aspasia	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Nucleatidae inside Terebratulida. Benthic fauna found in the black slate.
Zeilleria[40]	Zeilleria mutabilis Zeilleria bicolor ?Zeilleria aquilina	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, type member of the family Zeilleriidae inside Terebratulida. Relatively abundant on slope depostits, Z. aqulina represents incomplete specimens whose identification is rather complex.
Bakonyithyris[40]	Bakonyithyris avicula Bakonyithyris pedemontana Bakonyithyris apenninica Bakonyithyris ovimontana	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Zeilleriidae inside Terebratulida. A regional genus, limited mostly to the Bakony mountains and linked with Fe deposition.
Eplenyithyris[40]	Eplenyithyris cerasulum	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, incertade sedis inside Terebratulida. It was first identified on the Épleny quarry
Viallithyris[40]	Viallithyris gozzanensis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, incertade sedis inside Terebratulida. Rather less abundant than other genera, but based on more complete specimens. Is linked with Italian fossils of the same age.
Rhapidothyris[40]	Rhapidothyris cf. ovimontana	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Lobothyrididae inside Terebratulida. Based on fragmentary specimens
Securithyris[40]	Securithyris adnethensis Securithyris filosa Securithyris paronai	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Pygopidae inside Terebratulida. A more basinal genus
Liospiriferina[40]	Liospiriferina sicula Liospiriferina cf. globosa Liospiriferina gryphoidea Liospiriferina alpina	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Spiriferinidae inside Spiriferinida. Abundant on the slope deposits, but rather rare on the basinal settings
Cisnerospira[40]	Cisnerospira darwini	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Mentzeliidae inside Spiriferinida. Rather rare
Gibbirhynchia[40]	Gibbirhynchia cf. orsinii	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Tetrarhynchiidae inside Rhynchonellida. A genus common on the Sinemurian-Toarcian of the Mediterranean rela, but on this deposits is based on incomplete specimens.
Jakubirhynchia[40]	? Jakubirhynchia cf. fascicostata ? Jakubirhynchia aff. laevicosta	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Basiliolidae inside Rhynchonellida. Is based on very fragmentary remains.
Apringia[40]	Apringia diptycha Apringia paolii Apringia piccininii	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Basiliolidae inside Rhynchonellida. Diverse, but only on slope deposits.
Prionorhynchia[40]	? Prionorhynchia hagaviensis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, type member of the family Prionorhynchiidae inside Rhynchonellida. Rare and based on very fragmentary specimens
Lokutella[40]	Lokutella kondai Lokutella liasina Lokutella palmaeformis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Prionorhynchiidae inside Rhynchonellida. Diverse, but not abundant.
Nannirhynchia[40]	Nannirhynchia gemmellaroi Nannirhynchia reynesi	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Norellidae inside Rhynchonellida. A small genus
Pisirhynchia[40]	Pisirhynchia pisoides Pisirhynchia retroplicata	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Norellidae inside Rhynchonellida. Abundant, related with Silica deposits.
Kericserella[40]	Kericserella inversaeformis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Norellidae inside Rhynchonellida. Abundant, related with Silica deposits.
Fenyveskutella[40]	Fenyveskutella vighi Fenyveskutella pseudouhligi	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Rhynchonellatan, member of the family Norellidae inside Rhynchonellida. Abundant, linked with basinal deposits

Gastropoda

Gastropoda
Genus	Species	Material	Location	Notes	Images
Dohmella[41]	Dohmella multistriatus	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Oriostomatidae inside Euomphalina. Was identified originally as "Riselloidea cf. multistriata"
Worthenia[41]	Worthenia superstes	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Murchisoniina inside Lophospiridae. It was first identified on the Bakony Mountains
Sisenna[41]	Sisenna pinguis Sisenna subturrita	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Pleurotomarioidea inside Pleurotomariidae. The most diverse local Pleurotomarid, is also linked with large Microbial accumulations.
Laevitomaria[41]	Laevitomaria periferialis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Pleurotomarioidea inside Pleurotomariidae. Abundant on deposits with Terrigenous inputs
Discohelix[41]	Discohelix orbis	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Discohelicidae inside Vetigastropoda. Abundant on deposits with Terrigenous inputs
Amberleya[41]	Amberleya alpina	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Eucyclidae inside Seguenzioidea. Abundant on deposits with Terrigenous inputs
Austriacopsis[41]	Austriacopsis austriaca	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Fissurellidae inside Fissurelloidea. Related with Snails found in coeval deposits in Austria.
Anticonulus[42]	Anticonulus lateumbilicatus	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Top Snail, member of the family Trochidae inside Trochoidea. Is found associated with Crinoid debris
Lewisiella[42]	Lewisiella acicula	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Ataphridae inside Trochoidea. Is found associated with Crinoid debris
Proconulus[42]	Proconulus epuloides	Cunchs	Úrkút quarry. Épleny quarry Kericser (Lókút).	A Sea Snail, member of the family Proconulidae inside Trochoidea. Is found associated with Crinoid debris

Cephalopoda

Cephalopoda
Genus	Species	Material	Location	Notes	Images
Calliphylloceras[38][43]	Calliphylloceras spadae	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, member of the family Phylloceratidae inside Phylloceratida. Was the main identified ammonite locally on Úrkút, and is related to great concentrations of Fe.
Zetoceras[38][43]	Zetoceras cf. zetes	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, member of the family Phylloceratidae inside Phylloceratida. It is based on more complete specimens than other local Ammonites.
Protogrammoceras[38][43]	Protogrammoceras (Paltarpites) paltum Protogrammoceras sp.	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, member of the family Hildoceratidae inside Ammonitida. The most abundant, linked with specimens from north Italy.
Hildaites[38][43]	Hildaites crassus Hildaites cf. forte Hildaites sp.	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, member of the family Hildoceratidae inside Ammonitida. The most diverse, related with specimens from Germany and Austria, but also north Italy.
Dactylioceras[38][43]	Dactylioceras sp.	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, type member of the family Dactylioceratidae inside Ammonitida. Related with specimens from Germany and Austria.
Lytoceras[38][43]	Lytoceras sp.	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	An Ammonite, type member of the family Lytoceratidae inside Ammonitida. Related with specimens from Germany and Austria.
Cenoceras[38][43]	Cenoceras aratus	Cunchs	Úrkút quarry. Épleny quarry Csernye quarry	A Nautilidan, type member of the family Cenoceratidae. A well distributed genus between the Sinemurian-Toarcian, found on Germany, England, Austria, Italy, etc.

Actinopterygii

Actinopterygii
Genus	Species	Material	Location	Notes	Images
Leptolepis[38]	Leptolepis normandica	More than 30 fishes	Úrkút quarry. Épleny quarry	An Osteichthyes, type member of the family Leptolepididae inside Teleostei. On the fracture surfaces of the Shale, many mica flakes can be observed, along with the enrichment of fossils, including this genus. The Most abundant fish genus recovered locally, probably formed large Schools. Is linked to the Toarcian biota of Germany and England.
Eomesodon[6]	Eomesodon sp.	Single Complete Specimen	Úrkút quarry.	An Osteichthyes, member of the family Pycnodontiformes inside Neopterygii. It is located on the dorsal side, with the skull bones frontal and parietal are strongly intertwined it extends strongly towards the anterior end of the skull. It has an interoperculum larger than any other fish taxon. The posterior scales on the fossil is characterized by the appearance of a 2–3-pronged spike.[6]
Caturus[6]	Caturus sp.	Single Complete Specimen	Úrkút quarry.	An Osteichthyes, type member of the family Caturidae inside Amiiformes. On the skull the operculum and the praeoperculum are long and close contact. There is a single epidural plate that connects to the dorsal extension of the vertebral body.[6]
Dapedium[44]	Dapedium sp.	Single Complete Specimen	Úrkút quarry.	An Osteichthyes, type member of the family Dapediidae inside Holostei. The Dapedium specimen from Úrkút is the first articulated Mesozoic fish body fossil from Hungary that is described in detail.[44] The preserved cranium reveals important characters, although species-level identification is hindered by suboptimal preservation of some diagnostic features.[44]

Fungi

Fungi
Genus	Species	Material	Location	Notes	Images
Hyphae[45]	Hyphae sp	Hyphas	Úrkút quarry. Épleny quarry	Uncertain types of plant parasite Fungi. It was impossible to identificate the specimens found. Spores located on the manganese ores had hypha threads. Some fungus rests occurred on disorganized higher plant rests, being probably parasitic or saprophytic vegetations, occurring in direct ratio with the plant rest.
Ornatisporites[46]	Ornatisporites urkutensis	Fungal Spores	Úrkút quarry. Épleny quarry	Fungal spores of uncertain assigantion, probably Ophiostomatales. O. urkutensis is known only from Úrkút and related with Plant spores, probably being a parasyte fungus.

Palynology

Palynology
Genus	Species	Material	Location	Notes	Images
Micrhystridium[45][46][7]	Micrhystridium arachnoides Micrhystridium recurvatum	Acritarchs	Úrkút quarry. Épleny quarry	An Acritarch, probably related with Chloroplastida. Possible organic matter from green algae.
Crassosphaera[45][46]	Crassosphaera concinna	Cysts	Úrkút quarry. Épleny quarry	Affinities with the family Prasinophyceae inside Chloroplastida. Green Algae Cysts, related with oxygenated waters.
Pleurozonaria[46]	Pleurozonaria concinna	Cysts	Úrkút quarry. Épleny quarry	Affinities with the family Prasinophyceae inside Chloroplastida. Green Algae Cysts, related with oxygenated waters.
Tytthodiscus[46]	Tytthodiscus mecsekensis	Cysts	Úrkút quarry. Épleny quarry	Affinities with the family Prasinophyceae inside Chloroplastida. Green Algae Cysts, related with oxygenated waters.
Hystrichosphaeridium[7]	Hystrichosphaeridium sp.	Cysts	Úrkút quarry. Épleny quarry	Affinities with the family Goniodomaceae inside Dinophyceae. Green Algae Cysts, related with oxygenated waters.
Alisporites[45][46][7]	Alisporites inaequalis Alisporites thomasii Alisporites sp.	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Gymnospermophyta inside Gymnospermae. Unclassified Gymnosperm spores
Dictyotriletes[45][46][7]	Dictyotriletes deaki Dictyotriletes variegatus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Gymnospermophyta inside Gymnospermae. Unclassified Gymnosperm spores
Exesipollenites[7]	Exesipollenites scabrosus Exesipollenites tumulus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Gymnospermophyta inside Gymnospermae. Unclassified Gymnosperm spores
Pityosporites[7]	Pityosporites illustris	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Gymnospermophyta inside Gymnospermae. Unclassified Gymnosperm spores
Vitreisporites[46][7]	Vitreisporites craigii Vitreisporites pallidus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Gymnospermophyta inside Gymnospermae. Unclassified Gymnosperm spores
Staplinisporites[46]	Staplinisporites hungaricus	Spores	Úrkút quarry. Épleny quarry	Affinities with the Bryophyta inside Embryophyta. Moss Spores from humid settings.
Sphagnumsporites[46]	Sphagnumsporites clavus Sphagnumsporites psilatus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Sphagnaceae inside Bryophyta. Moss spores from humid settings.
Concavisporites[46]	Concavisporites polygonalis	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta. Unclassified fern spores
Corrugatisporites[45][46]	Corrugatisporites arcuatus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta. Unclassified fern apores
Polycingulatisporites[45][46]	Polycingulatisporites circulus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta. Unclassified dern apores. P. circulus was identified first on Úrkút.
Toroisporites[45][46]	Toroisporites transdanubicus Toroisporites (Toripunctisporis) hungaricus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta.
Triplanosporites[46]	Triplanosporites couperi Triplanosporites goczani Triplanosporites manganicus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta. Unclassified Fern Spores.
Verrucosisporites[46]	Verrucosisporites rarus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridophyta inside Tracheobionta. Unclassified Fern Spores. T. transdanubicus was identified first on Úrkút.
Trilites[45][46]	Trilites verrucatus Trilites couperi Trilites pulcher	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Filicopsida inside Tracheobionta. Unclassified Fern Spores. T. verrucatus was identified first on Úrkút.
Clavatisporites[46][7]	Clavatisporites clarus Clavatisporites microcapitulus Clavatisporites minor Clavatisporites platycapitulus Clavatisporites pulcher	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridopsida inside Tracheobionta. Unclassified Fern Spores
Laevigatosporites[46]	Laevigatosporites ovatus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridopsida inside Tracheobionta. Unclassified Fern Spores
Leiotriletes[45][46]	Leiotriletes brevilaesuratus Leiotriletes manganicus Leiotriletes pflugii Leiotriletes sphagnoides Leiotriletes transdanubicus Leiotriletes urkutensis	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridopsida inside Tracheobionta. Unclassified Fern Spores. L. pflugii, L. transdanubicus and L. urkutensis where identified first on Úrkút.
Hamulatisporis[46]	Hamulatisporis sp.A sp. nov. Hamulatisporis sp.B sp. nov.	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Lycopodiaceae inside Lycophyta. Lycopod Spores, related with low herbaceous flora found associted with humid environments.
Lycopodiumsporites[45]	Lycopodiumsporites clavatoides	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Lycopodiaceae inside Lycophyta. Lycopod Spores, related with low herbaceous flora found associted with humid environments.
Obtusisporis[46][7]	Obtusisporis divisitorus Obtusisporis hexagonalis Obtusisporis kara-murzae Obtusisporis mesozoicus Obtusisporis reductus Obtusisporis undulus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Lycopodiaceae inside Lycophyta. Lycopod Spores, related with low herbaceous flora found associted with humid environments.
Punctatisporites[45][46]	Punctatisporites circulus Punctatisporites goczani Punctatisporites krutzschi Punctatisporites rotundus Punctatisporites sp.	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Lycopodiaceae inside Lycophyta. Lycopod Spores, related with low herbaceous flora found associted with humid environments.
Perotrilites[45][46]	Perotrilites pseudoreticulatus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Selaginellaceae inside Lycophyta. Herbaceous fern spores, linked to open humid environments
Klukisporites[46]	Klukisporites deaki	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Schizaeaceae inside Schizaeales. Herbaceous fern spores, linked to open humid environments
Undulatisporites[45][46]	Undulatisporites sp	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Schizaeaceae inside Schizaeales. Herbaceous fern spores, linked to open humid environments
Contignisporites[46]	Contignisporites zolyomii	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Pteridaceae inside Polypodiopsida. Fern spores related with large colonies on humid settings.
Dictyophyllidites[46][7]	Dictyophyllidites crassiexinus Dictyophyllidites crassitorus Dictyophyllidites curvitorus Dictyophyllidites hungaricus Dictyophyllidites macrosinus Dictyophyllidites mortoni Dictyophyllidites rectitorus Dictyophyllidites reissingeri Dictyophyllidites transdanubicus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Matoniaceae inside Gleicheniales. Fern spores related with modern genera that grew forming large colonies in tropical locations. The great diveristy suggest this fern grows on sections proximal to the seashore.
Marattisporites[46]	Marattisporites scabratus	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Marattiaceae inside Marattiopsida. Fern spores related with modern genera that grew forming large colonies in tropical locations.
Cyathidites[45][46]	Cyathidites minor Cyatheacidites sp	Spores	Úrkút quarry. Épleny quarry	Affinities with the family Cyatheales inside Polypodiopsida. Tree Fern spores, related with humid environments. C. minor was first identified on the Úrkút deposits.
Caytonipollenites[45]	Caytonipollenites pallidus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Caytoniales inside Pteridospermatophyta. Pollen from large arboreal to arbustive ferns, related with tropical settings.
Pteruchipollenites[45][46]	Pteruchipollenites thomasii	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Umkomasiaceae inside Corystospermaceae. Pollen from large arboreal to arbustive ferns, related with tropical settings.
Eucommiidites[45][46][7]	Eucommiidites troedssonii Eucommiidites rugulatus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Cycadales inside Cycadopsida. Originally identified as pollen from possible early angiosperms, is now classified as comin from Cycas and relative arbustive to arboreal flora.
Cycadopites[46]	Cycadopites sp	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Cycadales inside Cycadopsida.
Bennettitaceaeacuminella[46]	Bennettitaceaeacuminella simplex	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Bennettitales inside Spermatopsida. Medium to large sized Cycad-like flora pollen.
Monosulcites[45][46][7]	Monosulcites minimus Monosulcites urkutiensis	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Bennettitales inside Spermatopsida. Originally identified as pollen from possible early Angiosperms, is now classified as coming from Bennetitales, that are closely related with the true flowering plants. As its name suggest, M. urkutiensis was first described on Úrkút.
Paracirculina[7]	Paracirculina tenebrosa	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Bennettitales inside Spermatopsida. A Hygrophyte pollen, related with dry lowlands.
Ginkgoretectina[46]	Ginkgoretectina ferrei Ginkgoretectina punctata Ginkgoretectina sp	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Ginkgoaceae inside Ginkgoopsida. Pollen that resembles the modern Ginko pollen.
Classopollis[45][46][7]	Classopollis torosus Classopollis classoides Classopollis grandis Classopollis minor	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Cheirolepidiaceae inside Coniferales. Coniferous pollen related to dy and hot settings, abundant on the Toarcian Afro-Mediterranean realm.
Corollina[46]	Corollina meyeriana	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Cheirolepidiaceae inside Coniferales. Coniferous pollen related to dy and hot settings, common alongside with Classopollis.
Spheripollenites[45][46][7]	Spheripollenites scabratus Spheripollenites subgranulatus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Cheirolepidiaceae inside Coniferales. Coniferous pollen related to dy and hot settings.
Parvisaccites[46]	Parvisaccites enigmatus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Podocarpaceae inside Coniferales. Associated with Classiopollis on dry environments.
Cerebropollenites[46]	Cerebropollenites macroverrucosus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Pinidae inside Coniferales. Associated with Classiopollis on dry environments.
Inaperturopollenites[45]	Inaperturopollenites globulus Inaperturopollenites parvoglobulus	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Pinidae inside Coniferales. Associated with Classiopollis on dry environments.
Monocolpopollenites[45]	Monocolpopollenites sp.	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Magnoliophyta inside Cycadophytanae. Pollen similar of the modern angiosperm pollen.
Tricolporopollenites[45]	Tricolporopollenites cingulum	Pollen	Úrkút quarry. Épleny quarry	Affinities with the family Dilleniidae inside Magnoliopsida. Pollen similar of the modern angiosperm pollen.

Fossil Wood

Wood
Genus	Species	Material	Location	Notes	Images
Pteridospermaexylon[47][48][49][50][51][52]	Pteridospermaexylon theresiae	Wood	Épleny quarry	Affinities with the family Gymnospermophyta, incertade sedis.[52]
Baieroxylon[47][48][49][50][51][52]	Baieroxylon lindicianum	Wood	Épleny quarry	Affinities with the family Ginkgoaceae inside Ginkgoopsida. Shows radial pitting is of mixed type, mostly uniseriate, radial pits forming small or long chains; cross-fields are of araucarioid type. It is labelled "Eplény, kovasodott fatörzs" (Eplény, silicificd wood).[52]
Simplicioxylon[53][47][48][52][54]	Simplicioxylon hungaricum	Wood	Úrkút quarry. Épleny quarry	Affinities with the family Cheirolepidiaceae inside Coniferales. It was at the first suggested to come from the Cretaceous period.[53] Then was found to be from the Toarcian.[47] The local fossil wood is impregnated in manganese, what can be a further evidence for hydrothermal source for the local metals.[54] The wood of Simplicioxylon hungaricum is widespread on the lias of Europe, from the Hettangian to the Mid-Aalenian.[54]
Pseudagathoxylon[47][48][49][50][51]	Pseudagathoxylon eplenyense	Wood	Úrkút quarry. Épleny quarry	Affinities with the family Cheirolepidiaceae inside Coniferales.[47]
Agathoxylon[53][47][48][49][50][51][52][54]	Agathoxylon agathiforme Agathoxylon parenchymatosum Agathoxylon sp. 1 Agathoxylon sp. 2 ? Agathoxylon sp. 3 ? Agathoxylon sp. 4 ? Agathoxylon sp. 5	Wood	Úrkút quarry. Épleny quarry	Affinities with the family Araucariaceae inside Coniferales. Assigned to Dadoxylon agathiforme, Agathoxylon mecsekense, Araucarioxylon resiniferum, Brachyoxylon sp., Dadoxylon sp. and Baieroxylon sp.[47] This Genus represent the most diverse wood found locally, with several assigned specimens of poor preservation, but that can confidently be referred to Agathoxylon.[52]
Araucarioxylon[47][48][49][50][51][52]	Araucarioxylon resiniferum Araucarioxylon sp Araucarioxylon sp. 2	Wood	Úrkút quarry. Épleny quarry	Affinities with the family Araucariaceae inside Coniferales. Shows a mixed type radial pitting, with pits half uniseriate half biseriate, and, in some cases only, triseriate.[52]
Torreyoxylon[47][48][49][50][51][52]	Torreyoxylon boureaui	Wood	Úrkút quarry.	Affinities with the family Araucariaceae inside Coniferales. Unique of úrkút, has been synonimized with Agathoxylon, although some trunks have different symmetry.[47] It was originally thought to come from Aptian clay (now Albian clay), although this partly silicified sample is probably reworked from Liassic layers.[52]
Callitrixylon[47][48][49][50][51][52]	Callitrixylon hungaricum	Wood	Úrkút quarry. Épleny quarry	Affinities with the family Cupressaceae inside Coniferales. This wood, poorly preserved, was only briefly mentioned, and is more probably conspecific with Platyspiroxylon sp. 2.[52]
Protelicoxylon[47][48][49][50][51][52]	Protelicoxylon parenchymatosum	Wood	Úrkút quarry.	Affinities with the family Taxaceae inside Coniferales. Labelled "Platyspiroxylon parenchymatosum, P. Greguss, Úrkút, István akna".[52]
Prototaxodioxylon[47][48][49][50][51][52]	Prototaxodioxylon sp.	Wood	Úrkút quarry.	Affinities with the family Taxaceae inside Coniferales. Labelled 'Técsbányatelep, András akna, 6. szint, 7. réteg, fővágat" [Pécsbányatelep, András shaft, 6th. level, 7th layer, main galery], the sample anatomy, with mixed pitting and taxodioid cross-fields, clearly points out the genus Prototaxodioxylon.[52]
Podocarpoxylon[47][48][49][50][51][52]	? Podocarpoxylon sp.	Wood	Úrkút quarry.	Affinities with the family Podocarpaceae inside Coniferales. Can be related with Araucarioxylon sp. 5 ?.[52]

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