A Veszprém Megyei Múzeumok Közleményei 12. (Veszprém, 1973)

Badinszky Péter: A Veszprém környéki felsőkarni fődolomit üledékföldtani vizsgálata

Unser Kenntnismaterial betreffs des oberkarnischen Hauptdolomits von Veszprém hat sich also durch die Ergebnisse dieser Untersuchungen weiter erweitert und es wurden im untersuchten Gebiet neuere AngaThe modern geological analysis of our home Triassic formations became a timely task, especially when we consider that the open levelling and faciès problems of Veszprém Carnian development have not yet been elucidated. Investigations were started in 1965 with the comprehensive geological survey of the Upper Carnian main dolomite, for recent mining and boring activities supplied enough basis to a more detailed material testing. The microstratigraphical experiments on the Upper Carnian main dolomite geological deposits were completed in 1969. As the result of the investigations, in the environs of Aranyos-völgy (Táborállás quarry, Jutas meadow), the real thickness of the Upper Carnian main dolomite proved to be exactly 80 m. (This datum well correlates with the subsequently made boring in 1971 in the rupture zone of the main dolomite in Aranyos-völgy.) Within this main dolomite stage marked by the presence of Megalodon triqueter pannonicus, on the basis of minero-petrological and palaeontological examinations, a trichomy was established: — Underneath, a 14-layer 37.5 m thick main dolomite deposit is present belonging to the Cornucardia hornigi stage with a similar dip as of marl. Primarily fine-grained but, at places, with marl, a layer group poor in faunal elements. — In the middle, a 10-layer 29.0 m thick mediumgrained main dolomite is found, which may be characterized by M. triqueter pannonicus FRECH virency. — Above, an 8-layer 13.2 m thick fine-grained and medium-grained main dolomite is deposited. This group of layers may be faunistically characterized by an increase in the number of Megalodon species. In its ben zur Auseinanderhaltung des karnischen und des norischen Hauptdolomits geliefert. Péter Badinszky immediate cover, strikingly large species occur, most probably indicating Norian stage Megalodon giimbeli STPP., Megalodon hoernesi FRECH). On the basis of the investigations, in the Upper Carnian main dolomite gradual deposit formation was established within the layer, layer groups as well as within the stage. According to our opinion, dolomite formation taking place here must have occurred some what deeper than at the border of the intensive swash zone: it is indicated by the good preservation of small fossilic remains, Ostracoda shells, and the entirety of ooid grains. The general occurrence of algal remains suggest a maximum of 90 metres sea depth. Owing to early technical literature data, the Megalodon fauna of the Táborállás (Aranyos-völgy) quarries was considered to be small-sized, we also decided to apply a detailed measuring technique. Our measurements prove that, on the whole, the fauna may not be called dwarf at all, so much so, that in layer 21, the Megalodon species are strikingly large, with an average of 59 mm, presenting also an outstanding 180 mm long M. triqueter pannonicus in the Carnian stage. Dwarf type was shown to occur only in layer 15, where the decrease in dimensions may be accounted for the algal population hindering them both in movement and in growth. In conclusion, we may say that as the result of the present investigations, the knowledge of the Veszprém Upper Carnian main dolomite has increased, and many new data came forward regading the separation of the Carnian and Norian main dolomite of this region. Péter Badinszky INVESTIGATIONS INTO THE GEOLOGICAL DEPOSIT OF THE UPPER CARNIAN DOLOMITE IN THE ENVIRONS OF VESZPRÉM