Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 20. 2002. (Budapest, 2002)

New data to the stratigraphy TATZREITER & VÖRÖS 1991, BALLNI 1993, MJETTO & MANFRLN 1995). BALLNI (1993) and TATZRETTER & BALLNI (1993) avoided using the name "Binodosus" as zonal/

subzonal index. More recendy, MlETTO & MANFRLN (1995) suggested a completely new zonal/subzonal scheme for the Anisian (and also for the higher Triassic). There the Binodosus Subzone appeared as the uppermost part of the Pelsonian, more or less corresponding to the Zoldianus Subzone of VÖRÖS (1987). The index species seems to be contradictory in terms of its taxonomic interpretation and stratigraphie position. TATZRETTER & BALLNI (1993), when erecting the new genus Schreyerites, intentionally excluded the species Ceratttes binodosus (HAUER, 1851) and BALLNI (pers. comm. 2002) still holds this opinion. On the other hand, MlETTO & MANFRLN (1995) found the suture of their "C" Unodosus as a proper basis for assigning this species to Schreyerites. A more crucial problem lies in the contradictory data on the stratigraphie occurrence of "C." binodosus in the very important Anisian reference section of Dont. BALLNI (1993) found it in the level ß [corresponding to the upper part of Niveau 3 of ASSERETO (1971), and to the Binodosus Subzone of VÖRÖS (1987)], and this record is corifirmed (MUTTONI et al. 1998, BALLNI, pers. comm. 2002). On the other hand, MlETTO & MANFRLN (1995, and pers. comm. 2002) collected their "C." binodosus from the lower level R [corresponding to the lower part of Niveau 3 of ASSERETO (1971), and to Zoldianus Subzone of VÖRÖS (1987)], and this was the reason why they suggested a 'binodosus Subzone" of deeper position. The arguments of both groups of authors are reasonable, but the proper documentation (monographic descriptions or at least detailed logs with range charts) is still lacking in both cases. These unsolved contradictions force us to abandon the use "Binodosus" as a subzonal name. We niaintain the Zoldianus Subzone as defined by VÖRÖS (1987) and correlated by TATZRETTER & VÖRÖS (1991). The subsequent biostratigraphic interval is characterised by the occurrence of the species "C binodosus" (sensu ASSERETO 1971, BALLNI 1993 and VÖRÖS 1987) accompanied by Judicarites and Longobardites, but in this study we keep this unit provisionally unnamed We assign this unnamed subzone to the top of the Pelsonian, with its theoretical upper boundary drawn at the first appearance of Paraceratites (i.e., base of Trinodosus Zone, Ulyrian). The Giudicarie sections (e.g. Stabol Fresco, BALLNI et al. 1993) are best suited for drawing this boundary, whereas, due to their scanty fossil record in this interval, neither the Balaton Hghland, nor the Dont sections are useful in this respect. 2. The two levels oj

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brachiopod ("Recoaro") limestones An unusual feature of the Horog-hegy section is that the brachiopod limestone ("Recoaro" Limestone, or "Horoghegy Member") appears in two distinct, biostratigraphically welldated levels in the Balatonicus Subzone and at the top of the Zoldianus Subzone. In other sections of the Balaton Ftt^gLrlaiid, where this member of the FLF is known, it occurs at only one level. It was dated by ammonoids in the Aszofô section where it belongs to the Balatonicus Subzone (PÁLFY 1986, TATZTIFJTER & VÖRÖS 1991). In the Felsöörs section the of the Pelsonian Substage 57 crinoicy-bracruopodal limestone beds were assigned to the Binodosus Subzone (VÖRÖS 1998), whereas earlier records suggest that they may also represent the highest part of the Zoldianus Subzone (SZABÓ et aL 1980). Thus the "Recoaro" beds at Aszofô and Felsöörs show remarkable correlation with the two levels of the Horog-hegy section (Figure 3). It must be noted, however, that in contrast to the less than one metre thick "Recoaro" levels at Köveskál, the crmoicM-bracHopodal limestones form several metres thick intervals both at Aszófö and Felsöörs. TAGE LU UBZONE LOCALITIES >> 6 S in c c ~ O CU c CO CO O N UBZONE KÖVESASZÓFELSŐo E > ß -5 <" CO CO KÁL FŐ ÖRS unnamed e -z. < Balatonicus co e PELSONI Balatonicus Zoldiani icus c o ro o ro m Figure 3 — Correlation chart of the two levels of "Recoaro" limestone in well-dated sections of the Balaton Highland with a possible interpretation of the events. — 1: Isolation of surviving Tagyon-type carbonate platforms; 2: Fragmentation and demise of carbonate platforms. The two levels of brachiopod ("Recoaro") limestones of the Horog-hegy section show subtle differences. At each level, twenty species were identified, of which 16 occur at both horizons. By far the most abundant species are Tetractinella trigonella and Mentzelia mentzeli in both the lower and the upper brachiopod bed The designation of a Mentzelia mentzeli-Tetractinella trigonella association, first observed in the material collected mostly from the upper bed (PÁLFY 1991), is thus applicable to both horizons. The lower bed yielded several rare species, which were previously only known from Aszófő in the Balaton riighland area. These include Volirbyncbia cf. projectifrons, Homoeorhyncbia ? sp., Sulcatinella incrassata, and "Pexidella" aff. sturi. A lithological similarity between the lower brachiopod limestone of Köveskál and that of Aszófő was also noted, and the preservation of brachiopods from these two localities is comparable. The most striking preservational difference between the two brachiopod beds at Köveskál is that T. trigonella occurs as mosdy articulated valves at the lower level, whereas at the upper level the majority of specimens are disarticulated valves.