The Csehbánya Formation is a geological formation in the Transdanubian Mountains of Veszprém County, Hungary. The formation dates to the Late Santonian (around 85-84 million years ago) of the Late Cretaceous. It represents a floodplain environment as opposed to the swampy lacustrine environment of the simultaneous , though there is complete overlap in terms of fauna. It underlies the , and laterally transitions to the Ajka Coal Formation.[1]
The lithology of the unit is a cyclic variation of conglomerate, sandstone, variegated siltstone, clay and marl layers with some sporadic thin coal seams.[2] It is uncomfortably overlies the Late Triassic Main Dolomite Formation, which has deposits of the Upper Cretaceous Nagytárkány Bauxite Formation within deep karstic sinkholes in the formation. There is a basal conglomerate of dolomite clasts at the base of the Csehbánya formation. The main exposed portion of the formation is called the Iharkút locality, which is a disused bauxite quarry. At this location due to Paleogene uplift, it is uncomfortably overlain by the Lutetian Ikharkút Conglomerate. In the upper levels of the formation, there are sandstone lens beds present, which represent channel bodies. These are indicative of an anastomosing fluvial system. The exposure at this locality is between 100–150 m. Most of the fossils are found within the SZ-6 site at the locality, which is interpreted as a lag channel deposit
Invertebrate paleofauna[]
Amber is known from both the and Csehbánya Formations, and is commonly referred to as ajkait. However most of the arthropod inclusions in these are undescribed, only being shown in photographs,[3] With only two species of Ceratopogonids (biting midges) in the extant genus Leptoconops and the extinct genus Adelohelea being described.[4] A list of known taxa is given below.
^Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 588-593. ISBN0-520-24209-2.
^Makádi, L., Botfalvai, G., Ősi, A. 2006: Egy késő-kréta kontinentális gerinces fauna a Bakonyból: halak, kétéltűek, teknősök, gyíkok. Földtani Közlöny 136/4, pp. 487-502.
^ abŐsi, A. & Rabi, M., 2006. Egy késő-kréta kontinentális gerinces fauna a Bakonyból II.: krokodilok, dinoszauruszok, pteroszauruszok és madarak (The Late Cretaceous continental vertebrate fauna from the Bakony Mountains II: crocodiles, dinosaurs (Theropoda, Aves, Ornithischia), pterosaurs). Földtani Közlöny, 136, 4, 503–526.
^ abcdeŐsi, A.; Apesteguía, S.M; Kowalewski, M. (2010). "Non-avian theropod dinosaurs from the early Late Cretaceous of Central Europe". Cretaceous Research. 31 (3): 304–320. doi:10.1016/j.cretres.2010.01.001.
^Segesdi, Martin; Botfalvai, Gábor; Bodor, Emese Réka; Ősi, Attila; Buczkó, Krisztina; Dallos, Zsolt; Tokai, Richárd; Földes, Tamás (June 2017). "First report on vertebrate coprolites from the Upper Cretaceous (Santonian) Csehbánya Formation of Iharkút, Hungary". Cretaceous Research. 74: 87–99. doi:10.1016/j.cretres.2017.02.010. ISSN0195-6671.
^Szabó, Márton; Gulyás, Péter; Ősi, Attila (April 2016). "Late Cretaceous (Santonian) pycnodontid (Actinopterygii, Pycnodontidae) remains from the freshwater deposits of the Csehbánya Formation, (Iharkút, Bakony Mountains, Hungary)". Annales de Paléontologie. 102 (2): 123–134. doi:10.1016/j.annpal.2016.04.001. ISSN0753-3969.
^Szentesi, Zoltán; Gardner, James D.; Venczel, Márton (March 2013). "Albanerpetontid amphibians from the Late Cretaceous (Santonian) of Iharkút, Hungary, with remarks on regional differences in Late Cretaceous Laurasian amphibian assemblages". Canadian Journal of Earth Sciences. 50 (3): 268–281. Bibcode:2013CaJES..50..268S. doi:10.1139/e2012-024. ISSN0008-4077.
^Szentesi, Zoltán; Venczel, Márton (April 2012). "A new discoglossid frog from the Upper Cretaceous (Santonian) of Hungary". Cretaceous Research. 34: 327–333. doi:10.1016/j.cretres.2011.11.012. ISSN0195-6671.
^Ősi, Attila; Clark, James M.; Weishampel, David B. (2007-02-01). "First report on a new basal eusuchian crocodyliform with multicusped teeth from the Upper Cretaceous (Santonian) of Hungary". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 243 (2): 169–177. doi:10.1127/0077-7749/2007/0243-0169. ISSN0077-7749.
^Rabi, Márton; Sebők, Nóra (October 2015). "A revised Eurogondwana model: Late Cretaceous notosuchian crocodyliforms and other vertebrate taxa suggest the retention of episodic faunal links between Europe and Gondwana during most of the Cretaceous". Gondwana Research. 28 (3): 1197–1211. Bibcode:2015GondR..28.1197R. doi:10.1016/j.gr.2014.09.015. ISSN1342-937X.
^ abcŐsi, A.; Butler, R.J.; Weishampel, David B. (2010). "A Late Cretaceous ceratopsian dinosaur from Europe with Asian affinities". Nature. 465 (7297): 466–468. Bibcode:2010Natur.465..466O. doi:10.1038/nature09019. PMID20505726. S2CID205220451.
^Ösi, Attila (2005). "Hungarosaurus tormai, a new ankylosaur (Dinosauria) from the Upper Cretaceous of Hungary". Journal of Vertebrate Paleontology. 25 (2): 370–383. doi:10.1671/0272-4634(2005)025[0370:htanad]2.0.co;2.
^Gareth J. Dyke, Attila Ősi (2010). "A review of Late Cretaceous fossil birds from Hungary". Geological Journal. 45 (4): 434–444. doi:10.1002/gj.1209.CS1 maint: uses authors parameter (link)