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the preserved cores, 35 samples were taken for petrographic studies and paleontological investigations. About 170 thin sections from the archive of the Geological and Geophysical Institute of Hungary were also used for microfacies and
Three shallowing upward and one deepening upward depositional cycles were described from the Upper Julian to Lower Tuvalian (Carnian) Sándorhegy Limestone Formation from the Balatonhenye – Barnag area. Lithological and microfacies characteristics of the depositional cycles suggest contemporaneous platform and basin sedimentation. Coarsening upward feature is certainly characteristic for Cycle I, yet progradation is doubtful. Cycle II represents platform sedimentation consisting of calcareous peritidal unit that progrades into the adjacent basin. Coeval deeper water sediments were mixed showing a coarsening upward trend from terrigenous mudstones to calcareous wacke-packstones (slope sediments) and grainstones (shoals). These cycles are asymmetric and were driven only by eustatic sea-level changes. Cycle IIIa, developed only in the basin, shows a gradual deepening upward trend. The laterally equivalent cycle on the platform is confined to an erosional hiatus. Tectonic subsidence along with eustatic sea-level rise may controlled the deposition of IIIa. We propose that tectonism may have been one of the plausible causes for the cessation and the following erosion of the Ederics Platform. Consequently, recolonization couldn't take place during the subsequent eustatic sea-level rise thus the source of IIIb prograding carbonate unit shifted to the Sédvölgy Platform.
. 1995: A budakalászi édesvizi mészk\H{o} mikrofácies vizsgálata (Microfacies study of the Budakalász travertine). - Diplomamunka., ELTE, Alkalmazott és Környezetföldtani Tanszék, 98 p. (In Hungarian.) A
Quaternary thermogene and meteogene travertine occurs globally, both in Hungary and abroad. Size and thickness of the individual deposits are highly variable. They can be classified on the basis of water temperature, morphological setting, depositional environment, microfacies and fabric. All travertine is composed of pure low magnesian calcite and its stable isotopic composition (d13C, d18O) may change according to the facies. Sr and Ba are typical and some places enrichment of heavy metals, U, Th, and REE were also reported. Travertine is generally related to karst water springs; therefore, tectonically-controlled karstification, cave and soil formations are very common. It can be rich in fossils and its water depth varies from some centimeters to tens of meters. Chronology and timing of travertine can be solved by applying numerical, calibrated and correlative methods.
The Pleistocene travertine of Buda Vár-hegy (Castle Hill) has been studied in subsurface galleries and cellars. Lithological variations, sedimentary features of the travertine and the underlying friable chalky carbonates and calcareous clays were described in the field. Four lithotypes and several microfacies types of travertine have been identified. The stratal pattern of travertine, distribution of lithotypes, the macrofauna, and the presence of microbial sediments suggests that the travertine was deposited in a shallow lake environment. The lake was fed by lukewarm springs from the central part (probably from Szentháromság-tér [Szentháromság Square] area), where the thickest travertine deposits are found. Direct evidence of cascade deposits or terraced tetarata deposits have not been found in the studied sections. The intense cementation and recrystallisation appear in the form of at least four, mostly phreatic, cement generations, including micrite envelopes, thin fibrous rims, thick radiaxial spars and pore occluding mosaics.
In the area of the town of Tata (Hungary) there are several Quaternary travertine outcrops, of which the Porhanyó Quarry is the best-exposed one. The travertine of the Porhanyó Quarry can be vertically divided into six units. Algal and other phytoclastic and phytohermal grainstone, boundstone and floatstone are the dominant microfacies. On the walls of the quarry carbonate vents and cones were detected; these forms are indicators of former spring activity at the bottom of a shallow lake. The lake, fed by thermal springs, was formed in a siliciclastic floodplain. The upwelling thermal water brought quartz and other detrital grains from the underlying Pannonian siliciclastic sediments to the surface, concentrating them in the vents. The three main phases of lacustrine evolution were interrupted first by a drying and flooding event, followed by a fluvial-eolian event and finally by eolian sedimentation. The oxygen isotope compositions of the vents differ from the values of vertical sections and slope samples, whereas the carbon isotope compositions show less variation. The different facies migrated during the evolution of the Tata Travertine Complex due to changes in morphology and flow direction. The integrated model of lake evolution suggests an upward cooling climatic trend, beginning with a humid Mediterranean climate in the early phase and closing with a cold, dry continental one in the late phase. The Tata Travertine Complex shows a marked d13C difference from the travertine occurrences of the Buda Mts. that is attributed to local effects. The ascending solutions at Tata may have infiltrated through organic-rich bedrocks and could have carried dissolved C enriched in 12C.
. 1966 36 491 505 Flügel, E. 2004: Microfacies of carbonate rocks. — Springer. 976 p
. 1982: Microfacies analysis of limestones. - Springer-Verlag, 633 p., Berlin, Heidelberg, New York. Microfacies analysis of limestones. 633
55 2 185 232 . E. Flügel 1982 Microfacies analysis of limestones Springer
Flügel, E. 1982: Microfacies Analysis of Limestones. - Spinger-Verlag, pp. 67-83. Gierlowski-Kordesch, E., J.C. Gómez Fernández, N. Meléndez 1991: Carbonate and coal deposition in an alluvial
