Balaton Highland Research Articles

Heavy mineral catalogue for the characterization and provenance of red sandstone macrolithic tools from Hódmezővásárhely-Gorzsa

Although ground stone tools (GSTs) are among the most abundant stone tools in archaeological sites, they are rarely investigated both from the archaeological and the geological point of view. There are many pieces made of siliciclastic sedimentary raw material. Their fragmentary condition makes it possible to examine them by slightly destructive methods, such HMA (heavy mineral analysis), which was developed primarily for siliciclastic rocks. Until now, ‘sensu stricto’ (s.str) heavy mineral analysis has not yet been carried out for ground stone tools, neither at the national nor at the international level. By comparing the heavy mineral compositions of the stone tools and their potential raw materials with the help of a newly developed HM descriptive system (including rutile, zircon, tourmaline, apatite and titanite), it is possible to determine the provenance of these archaeological materials. From the Neolithic tell of Gorzsa, 109 red sandstone macrolithic stone tools are known. These were separated into four, different types (‘Red–1’ – ‘Red–4’), based on the macroscopic and microscopic analysis. 11 fragments were chosen for HMA analysis. In addition, red-coloured sandstones from different geological occurrences of the Carpathian-Pannonian Basin (22 pieces) were also investigated. Based on the heavy mineral analysis, all raw material types of the stone tools could be originated from the Maros River and the Apuseni Mountains (Transylvania). However, the previously determined potential sources (Permotriassic and Miocene sequences from the Mecsek Mountains, Balaton Highlands, pebbles from the Danube River, and Papuk Mountains) cannot be excluded with absolute certainty from the possible raw materials.

Multimethodological Revisit of the Surface Water and Groundwater Interaction in the Balaton Highland Region—Implications for the Overlooked Groundwater Component of Lake Balaton, Hungary

The hummocky Balaton Highland is located in western Hungary and is part of the Transdanubian Mountains, the most extensive carbonate aquifer system in Hungary. The study region also encompasses Lake Balaton, the biggest lake in central Europe, which is to the south of Balaton Highland. The surface water–groundwater interaction in the Balaton Highland–Lake Balaton region and the groundwater contribution to Lake Balaton are revisited in this paper. Hydrostratigraphic classification was performed first; then, groundwater flow directions by hydraulic head distribution were analysed, and baseflow indices of surface watercourses were calculated. Regarding hydrochemical characterisation, general hydrochemical facies were identified, natural tracers of temperature, chloride and uranium were applied, and the stable isotopic composition of oxygen and hydrogen was determined. Finally, groundwater flow and heat transport were simulated in a 2D numerical model. A high level of hydraulic interaction was evidenced between surface water and groundwater and the sub-regions of Bakony Mountains, Balaton Highland and Lake Balaton by physical and chemical parameters, numerical simulation and groundwater-flow-related natural manifestations, revealing hydraulic continuity in the study region. Based on the results, the division of legislative water bodies can be reconsidered, especially that surface water and groundwater should be regarded as interconnected, and Lake Balaton can be considered a groundwater-dependent ecosystem in any water-use planning in the region.

Microbial Community Associated with Ground waters Discharge in Transylvania (Romania) and Balaton Highland (Hungary)

In the present study, water samples from 8 sites known as: Taploca, Nagy-borvíz, Piricske (located in Romania) and Szent Jakab, Kiskút, Kossuth Lajos, Polányi kút and Berzsenyi (located in Balaton highland in Hungary) and characterized with low nutrient content, were studied using cultivation independent methods. Diversity indices and cell counts were determined to assess the species richness in relation to the cell counts within the samples. Next generation sequencing was used to reveal the existing microbial community, and taxon specific PCR was used to detect the presence of some species with hygienic. 18 bacterial phyla above a ratio of 2% were identified in addition to 13 archaeal phyla using amplicon sequencing.

A mediterrán növényalkalmazás jelene és jövőbeli lehetőségei

In Hungary, the Mediterranean influence is more and more strongly featured typically by considerable climatic extremes between winter and summer. The Mediterranean vegetation has adapted to these changes and tolerates dry hot summers and mildly rainy winters. It will gain more and more space in the future both in public and private areas – mainly on the southern slopes of South Transdanubia and the Balaton Highlands, later maybe on the same southern slopes of Buda Mountains and the Velence Mountains, and afterwards in some areas of the Northern Middle Mountains. Thus it is useful to gain knowledge about the Mediterranean coastland’s vegetation and profit from it. Keeping in mind the economic water management, it is advisable to decide on drought and frost-tolerant species while planting them in a harmonic and decorative manner in orchards and lawn areas in the future. This is what the presented recommendations are for.

MIDDLE TRIASSIC (ANISIAN) CEPHALOPODS FROM THE MECSEK MOUNTAINS, HUNGARY

Recent nautiloid and ammonoid finds from the Middle Triassic Zuhánya Limestone Formation in the Mecsek Mountains (south Hungary) proved that the formation encompasses the whole Pelsonian and the lower Illyrian substages of the Anisian Stage. On the basis of 11 identified ammonoid species, the Balatonicus and Trinodosus zones have a complete record. The stratigraphical position of the Zuhánya Limestone on the whole corresponds to the Felsőörs Limestone in the Balaton Highland. The palaeobiogeographical evaluation of the cephalopod fauna showed that the elements of the nautilid fauna point mostly to Germanic and partly to Sephardic affinity. On the other hand, the ammonoid fauna has no Germanic elements; most of the species are Alpine in character, while the species Procladiscites brancoi indicates Dinaridic connection, or at least an occasional appearance of pelagic organisms. These results endorse the previous palaeogeographical assumption and suggest that during the Middle Triassic the Mecsek succession was situated along the European shelf, between the Vindelician-Bohemian Land and the open Tethyan Ocean.

Rediscovery of a classic Middle Triassic fossil site of the Balaton Highland (Transdanubian Range, Hungary): cephalopods, brachiopods and vertebrate remains from the Akol Hill at Barnag

Recent collecting of the classic Middle Anisian fossil site of the Akol Hill at Barnag (Nagyvázsony Plateau, Balaton Highland) yielded a plenty of new palaeontological data.The Middle Anisian platform carbonate succession (Tagyon Formation) is overlain by 1-2 metres thick reddish, nodular, crinoidal limestone (Vászoly Formation) that contains a very rich fossil assemblage with ammonoids, nautiloids and brachiopods. Some vertebrate fossils were also found. Besides fish teeth, remains of marine reptiles are also present in the fauna. Four vertebrae, a piece of a rib, as well as a tooth crown fragment have also been found.Based on the geological buildup and the new biostratigraphic data the active stage of the Barnag Platform was much shorter than that of the other two Middle Anisian platforms of the Balaton Highland (Tagyon Platform, Kádárta Platform). The ammonoid fauna of the lowermost thin limestone bed above the Tagyon Formation contains elements reworked from the Balatonicus Zone. The overlying some beds contain a very rich lower Illyrian ammonoid fauna which is more diverse than the equivalent faunas of the Tagyon Platform and the Kádárta Platform. The ammonites of the Balatonicus Zone in the basal part of the Vászoly Formation prove that the drowning of the Barnag Platform occured even during the Pelsonian, earlier than in the case of the Tagyon and the Kádárta Platforms where the oldest basin sediments are mid-Illyrian (Camunum Subzone of the Trinodosus Zone) above the drowning surface.The Akol Hill locality also provided the first known occurrence of ichthyosaurs like Cymbospondylus, predators that probably dwelled mostly open marine environments but also might have been well adapted for hunting in shallow environments like submarine highs.

Melt-rock interaction in the lower crust based on silicate melt inclusions in mafic garnet granulite xenoliths, Bakony–Balaton Highland

Major and trace element composition of silicate melt inclusions (SMI) and their rock-forming minerals were studied in mafic garnet granulite xenoliths from the Bakony–Balaton Highland Volcanic Field (Western-Hungary). Primary SMIs occur in clinopyroxene and plagioclase in the plagioclase-rich domains of mafic garnet granulites and in ilmenite in the vicinity of these domains in the wall rock. Based on major and trace elements, we demonstrated that the SMIs have no connection with the xenolith-hosting alkaline basalt as they have rhyodacitic composition with a distinct REE pattern, negative Sr anomaly, and HFSE depletion. The trace element characteristics suggest that the clinopyroxene hosted SMIs are the closest representation of the original melt percolated in the lower crust. In contrast, the plagioclase and ilmenite hosted SMIs are products of interaction between the silicic melt and the wall rock garnet granulite. A further product of this interaction is the clinopyroxene–ilmenite±plagioclase symplectite. Textural observations and mass ­balance calculations reveal that the reaction between titanite and the silicate melt led to the formation of these assemblages. We propose that a tectonic mélange of metapelites and (MOR-related) metabasalts partially melted at 0.3–0.5 GPa to form a dacitic–rhyodacitic melt leaving behind a garnet-free, plagioclase+clinopyroxene+orthopyroxene+ilmenite residuum. The composition of the SMIs (both major and trace elements) is similar to those from the middle Miocene calc-alkaline magmas, widely known from the northern Pannonian Basin (Börzsöny and Visegrád Mts., Cserhát and Mátra volcanic areas and Central Slovakian VF), but the SMIs are probably the result of a later, local process. The study of these SMIs also highlights how crustal contamination changes magma compositions during asthenospheric Miocene ascent.

Epigenetic-Hydrothermal Fluorite Veins in a Phosphorite Deposit from Balaton Highland (Pannonian Basin, Hungary): Signatures of a Regional Fluid Flow System in an Alpine Triassic Platform

The middle Anisian extensional tectonics of the Neotethyan realm developed a small, isolated carbonate platform in the middle part of the Balaton Highland (western Hungary), resulted in the deposition of uranium-bearing seamount phosphorite on the top of the drowned platform and produced some epigenetic fluorite veins in the Middle Triassic sequence. The stable C-O isotope data of carbonates are shifted from the typical Triassic carbonate ranges, confirming the epigenetic-hydrothermal origin of veining. Primary fluid inclusions in fluorite indicate that these veins were formed from low temperature (85–169 °C) and high salinity NaCl + CaCl2 + H2O type (apparent total salinity: 15.91–22.46 NaCl wt%) hydrothermal fluids, similar to parent fluids of the Alpine-type Pb-Zn deposits. These findings indicate that the Triassic regional fluid circulation systems in the Alpine platform carbonates also affected the area of the Balaton Highland. This is also in agreement with the previously established palinspatic tectonic reconstructions indicating that the Triassic carbonate and basement units in the Balaton Highland area were a part of the Southern Alpine. Similar fluorite veining in phosphorite deposits is also known in the Southern Alpine areas (e.g., Monte San Giorgi, Italy). Raman spectroscopic analyses detected H2 gas in the vapor phase of the fluid inclusions and a defect-rich fluorite structure in violet to black colored growth zones. This unique phenomenon is assumed to be the result of interaction between the uranium-rich phosphorite and the parent fluids of the epigenetic fluorite veins.

Red sandstone as raw material of Baden culture (Late Copper Age) grinding stones (Balatonőszöd - Temetői dűlő site, Hungary), with a review of the red sandstone formations of SW Hungary

Balatonőszöd - Temetői dűlő is one of the largest excavated and longest-lived sites of the Late Copper Age Baden Culture in Hungary, where 500 lithic finds were registered. In the site finds belonging to the late Middle Copper Age Balaton-Lasinja Culture and the Late Copper Age Boleraz Culture were found too.
 This paper presents petrographic and geochemical analyses of stone utensils, mostly of grinding stones, made of red, or discoloured white sandstones.
 Almost all sandstone artefacts are upper and lower stones of grinding equipment and polishers, as well as objects whose function is not known, worked and non-worked fragments; boulders of raw material are also in the studied set.
 The detailed petrographic and geochemical methods applied here are polarized light microscopy and a distribution study of the framework grains in thin section, and ICP-OES and ICP-MS as bulk rock chemical methods. The results were compared to published petrographic and geochemical data.
 Most of the studied artefacts were made of the rocks of the Red Sandstone and Siltstone Member of the Balaton Highland Sandstone Formation, especially from the mature type sandstone in which quartz is predominant, and which is almost free of feldspar. This type is characteristic of the confines of the Southern Balaton Highland and the lower part of the formation in the Northern Balaton Highland.
 A minor part of the studied artefacts - red or purple, purplish grey sandstones - originates from the sandstones of the Jakabhegy Sandstone Formation (Western Mecsek mountains).

Magyarország első közepes méretarányú (M=1:144.000) földtani térképsorozata a XIX. század második feléből

A Magyar Királyi Állami Földtani Intézet és jogutódjai 150 éves történetük alatt Magyarország geológiai térképezésének legfontosabb bázisintézményei voltak. Az intézet történetének első rendszeres, közepes méretarányú földtani térképműve Magyarország (nem teljes) 1:144,000 méretarányú geológiai térképsorozata volt. A térképmű a Habsburg Birodalom második katonai felmérésének nyomtatott ún. részletes térképeit használta topográfiai alapként, amelyre kézi színezéssel vitték fel a földtani tartalom felületi jeleit. A térképmű több szelvénye két, néhány pedig három, különböző színezésben is megtalálható az intézet könyvtárában. Minthogy a térképmű készítése megelőzte, ill. részben egybeesett a nemzetközi földtani jelkulcsot egységesítő bolognai kongresszussal, egyik változat színei sem egyeznek meg a ma szokásossal. Megadjuk a térképmű georeferálásához szükséges metaadatokat, illetve egy mintaterületen (Balaton-felvidék) bemutatjuk az 1:144 000-es térképművön és a mai földtani alaptérképen ábrázolt bazalt-területek kiterjedésének eltérését.

Value-saturated Education in Erzsébet Camps in Zánka, Hungary

The Erzsébet Camp in Zánka is located in the Balaton Highland, between Tihany and Badacsony. The Erzsébet Camps are one of the largest youth-project program in Hungary. Research data collection started in 2017, and it was carried out in three periods. The present study conducted analyses on a database compiled from findings of questionnaires administered to campers (2017, 2018 and 2019) and their chaperones (2018 and 2019). Data collection from the children and chaperones took place at the end of each camp shift and comprised of self-administered anonymous questionnaires with ten question blocks. The study conducts analyses of the database compiled from the main answers of more than 18,000 participants. Our research, exploratory in its nature, set out to compile the ”value map” of the Erzsébet Camps. The main focus of our interest was the added value and developmental effects of the camps with respect to campers. The another research question was what social values are transmitted and the preservation of which social values is supported by the Erzsébet Camps.

Olivine major and trace element compositions coupled with spinel chemistry to unravel the magmatic systems feeding monogenetic basaltic volcanoes

Monogenetic basaltic volcanic systems, despite their considerable smaller size and shorter lifetime compared to polygenetic volcanoes, can have complex pre-eruptive histories and composite volcanic facies architectures. Their source-to-surface investigation is essential for our better understanding of monogenetic volcanism and requires high-resolution mineral-scale analyses.In this study, we focus on diversely zoned olivine crystals and their spinel inclusions from alkaline basaltic volcanics that are the result of mixing of numerous magmas, crystals and fragments of various origins. The Fekete-hegy volcanic complex is one of the largest and most composite eruptive centers in the intracontinental monogenetic Bakony–Balaton Highland Volcanic Field (western Pannonian Basin, Eastern Central Europe). It is a compound multi-vent system built up by multiple eruption episodes: initial maar-forming phreatomagmatic eruptions were followed by massive lava flows and magmatic explosive activity. We performed stratigraphically controlled sampling in order to reveal the history of the successively erupted magma batches represented by the distinct eruptive units, as well as to discover the petrogenetic processes that controlled the evolution of the magmatic system.The juvenile pyroclasts of the phreatomagmatic eruption products (unit 1) contain a remarkably diverse mineral assemblage including five different olivine types and three distinct spinel groups. In addition, they comprise various xenoliths. Based on detailed textural investigations combined with in situ electron microprobe analyses, high-resolution laser ablation ICP-MS trace element mapping and single spot measurements on the variably zoned olivines of unit 1 samples, eight distinct environments are inferred to have been involved in their formation. Four of these environments account for the significant compositional variation of the olivine-hosted spinel inclusions. A complex set of open- and closed-system petrogenetic processes operated during the evolution of the magmatic system: magma stalling, accumulation, storage, fractionation, mixing, replenishments, cumulate remobilization, incorporation of foreign fragments and crystals from the wall rocks. All these diverse environments and processes resulted in the mixed character of the erupted magmas during the initial phreatomagmatic eruptive phase.In contrast, the uniform petrological features and the small variations shown by the olivines and spinels from unit 2–3 indicate that the later magmatic explosive – effusive phase was preceded by a considerable change in the magmatic system; it experienced a simple evolution through olivine + spinel fractional crystallization without any of the complexities seen during the initial phase.The present study emphasizes the importance of high-resolution mineral-scale textural and chemical investigations to unravel the complexity of the sub-volcanic magmatic systems feeding monogenetic basaltic volcanoes. Compared to the application of whole-rock geochemistry alone, this approach enables a direct and more detailed insight into the architecture and evolution of these systems.

A Badacsony freatomagmás piroklasztit-sorozata: következtetések a monogenetikus bazaltvulkáni működés folyamataira és formáira

A tanulmányban a Bakony–Balaton-felvidéki Vulkáni Terület (BBVT) legismertebb tanúhegyén, a Badacsonyon kibukkanó freatomagmás piroklasztit-sorozat első kvantitatív leírását és vulkanológiai értelmezését mutatjuk be. A piroklasztitok juvenilis / litikus törmelékeinek arányát pontszámlálásos módszerrel vizsgáltuk vágott kézipéldány-felszíneken. A felület%-ban kapott eredményeket a kőzetminták teljes térfogatára vonatkozónak vettük. E módszer segítségével meghatároztuk a freatomagmás robbanások relatív mélységét a szinvulkáni felszínhez képest, következtetéseket vontunk le a lehetséges szineruptív vulkánmorfológiára, valamint a terepi megfigyelések és korábbi tanulmányok alapján rekonstuáltuk a vulkán működésének teljes fejlődéstörténetét.
 A képelemzés során megállapítottuk litikus elegyrészek minimális arányát. Ebből, valamint a piroklasztitok térbeli elterjedéséből és rétegtani helyzetéből valószínűsíthető, hogy a Badacsony egy monogenetikus (esetleg policiklikus) tufagyűrű vagy sekély maar vulkán volt, amelynek kialakulásában a víz-magma kölcsönhatás következtében történt sekély mélységű freatomagmás robbanások játszották a fő szerepet. A tufagyűrű vulkáni forma a litoklasztok kis mennyiségével alátámasztható. Viszonylag kevés litoklasztot tartalmazó freatomagmás kitörési termékek nem csak tufagyűrűk, hanem puha, konszolidálatlan kőzeten kialakuló sekély maarok képződményei is lehetnek, amely modell a Badacsony esetében is valószínűsíthető.
 A terepi megfigyelések, valamint a képelemzés eredménye alapján a vulkanizmus freatomagmás robbanásos, lávaöntő és magmás robbanásos fázisokra osztható. Ezen adatok alapján vulkáni fejlődéstörténeti modellt állítottunk fel. A kevés korábbi, célzott vulkanológiai szemléletű munka miatt e „kezdeti” adatok megfelelő alapot adhatnak a további badacsonyi vulkanológiai kutatásoknak.

Tracing multiple resedimentation on an isolated karstified plateau: The bauxite-bearing Miocene red clay of the Southern Bakony Mountains, Hungary

The Vöröstó (=Red Lake) Formation, located in the Southern Bakony Mountains and the Balaton Highlands (Hungary), is a red, clayey continental assemblage containing hard, up to fist-sized bauxite pebbles, occurring in a large apparent stratigraphic gap between underlying karstified Triassic carbonates and mid’ Miocene to Quaternary cover. The origin and the exact stratigraphic position of the assemblage have been controversial for a long time. In this study, petrographic observations on the bauxite pebbles revealed common features with Cretaceous bauxite deposits known in the region, whereas heavy mineral composition of the red clay matrix is similar to those known from the Eocene bauxite horizon of the region. Single grain zircon U–Pb ages obtained from the bauxite pebbles and their red clayey matrix show similar late Archean to Jurassic age components. Additionally, Cenozoic U–Pb ages are well represented in the mostly euhedral zircon crystals separated from the red clays, whereas this volcanogenic contribution completely missing from the bauxite pebbles. SEM morphology and related EDX chemical analysis of clay minerals indicate polygenetic, detrital origin for the red clays. The main source material of the bauxite bearing Vöröstó Formation is most probably local Cretaceous and Eocene bauxite deposits exposed during the middle-late Miocene. These tropical weathering products were partly decomposed and degraded, but dilution by siliciclastic contribution is negligible. We suggest a transport mechanism dominated by local redeposition of mostly pelitic and allitic material through seasonal muddy debris flows within a karstic landscape.

Influence of upwelling on the sedimentation and biota of the segmented margin of the western Neotethys: a case study from the Middle Triassic of the Balaton Highland (Hungary)

In the Middle Anisian, extensional tectonic movements led to the development of a small isolated carbonate platform in the middle part of the Balaton Highland, Transdanubian Range, Hungary. In the Late Illyrian, a condensed pelagic carbonate succession with phosphorite horizons was formed on the top of the already drowned platform. These strata contain an extraordinarily diverse ammonite fauna. This unit is overlain by radiolarian-rich carbonates, locally with radiolarite interbeds. We suggest that the drowning process and the post-drowning sediment deposition were controlled partly by regional factors, i.e., the onset of opening of the Neotethys Ocean, and partly by local factors such as the bottom topography and related current activity, which may also be connected with the opening of the ocean. The predominance of the radiolarian-rich sediments suggests eutrophic surface water, which may be explained by a monsoon-driven upwelling model. The segmented sea-floor topography together with the high-fertility surface water conditions may have provided favorable habitats for the ammonites, which may have adapted to various ecological conditions, leading to extreme diversification of this group. Since similar Middle to Late Anisian evolution was reported from many other units of the western Neotethys margin, regional factors such as the establishment of an extensional tectonic regime and related marginal basin formation, monsoon-driven upwelling, and related high surface water productivity seem to be of critical importance in controlling the depositional conditions.

Changes of the karst landscape and epikarst system in the area of the Tapolca karst terrains, North-West Balaton Highlands, Hungary

Changes of the karst landscape and epikarst system in the area of the Tapolca karst terrains, North-West Balaton Highlands, Hungary

Wavelet analysis of low-frequency variability in oak tree-ring chronologies from east Central Europe

AbstractThis study investigates the low-frequency (interannual and longer period) variability in three hydroclimatic records from east Central Europe. Two of these records consist of climate proxies derived from oak-tree rings in Bakta forest, and Balaton Highlands in Hungary, for the time interval 1783-2003. The third record consists of homogenized instrumental precipitation data from Budapest, Hungary, from 1842 to 2003. Using wavelet analysis, the three time series are analyzed and compared with one another. It is found that all three time series exhibit strong interannual variability at the 2-4 years timescales, and these variations occur intermittently throughout the length of each record. Significant variability is also observed in all the records at decadal timescales, but these variations persist for only two to three cycles. Wavelet coherence among the various time series is used to explore their time-varying correlation. The results reveal significant coherence at the 2-4 years band. At these timescales, the climatic variations are correlated to the tree-ring signal over different time intervals with changing phase. Increased (decreased) contribution of large-scale stratiform precipitation offers a potential explanation for enhanced (faded) coherence at the interannual timescale. Strong coherence was also observed occasionally at decadal timescales, however these coherences did not appear uniformly. These results reinforce the earlier assertion that neither the strength nor the rank of the similarity of the local hydroclimate signals is stable throughout the past two centuries.

Constraints on the thickness and seismic properties of the lithosphere in an extensional setting (Nógrád-Gömör Volcanic Field, Northern Pannonian Basin)

The Nograd-Gomor Volcanic Field (NGVF) is one of the five mantle xenolith bearing alkaline basalt locations in the Carpathian Pannonian Region. This allows us to constrain the structure and properties (e.g. composition, current deformation state, seismic anisotropy, electrical conductivity) of the upper mantle, including the lithosphere-asthenosphere boundary (LAB) using not only geophysical, but also petrologic and geochemical methods. For this pilot study, eight upper mantle xenoliths have been chosen from Barna-Nagykő, the southernmost location of the NGVF. The aim of this study is estimating the average seismic properties of the underlying mantle. Based on these estimations, the thickness of the anisotropic layer causing the observed average SKS delay time in the area was modelled considering five lineation and foliation end-member orientations. We conclude that a 142–333 km thick layer is required to explain the observed SKS anisotropy, assuming seismic properties calculated by averaging the properties of the eight xenoliths. It is larger than the thickness of the lithospheric mantle. Therefore, the majority of the delay time accumulates in the sublithospheric mantle. However, it is still in question whether a single anisotropic layer, represented by the studied xenoliths, is responsible for the observed SKS anisotropy, as it is assumed beneath the Bakony–Balaton Highland Volcanic Field (Kovacs et al. 2012), or the sublithospheric mantle has different layers. In addition, the depths of the Moho and the LAB ( $$25\,\pm \,5, 65\,\pm \,10\,\hbox {km}$$ , respectively) were estimated based on S receiver function analyses of data from three nearby permanent seismological stations.

Ammonoid diversification in the Middle Triassic: Examples from the Tethys (Eastern Lombardy, Balaton Highland) and the Pacific (Nevada)

The diversity dynamics of the Anisian ammonoids is analyzed in terms of generic richness and turnover rates in one North American (Nevada) and two western Tethyan (Eastern Lombardy, Balaton Highland) regions. Two pulses of diversification are outlined: one in the middle Anisian (Pelsonian) and another near the end of the late Anisian (late Illyrian). The Pelsonian global diversification is interpreted as an effect of global sea-level rise. In the early late Anisian the ammonoid generic richness definitely decreased both in the western Tethys and in Nevada. The latest Anisian peak of ammonoid diversity was low in Nevada, which is explained by the uniform local sedimentary environment and the absence of major global changes. In the western Tethys the late Illyrian diversity peak was very prominent: ammonoid generic richness, turnover and proportion of originations were very high. This explosive peak is interpreted in terms of major changes of two regional environmental factors: coeval volcanic activity and ...

EVIDENCE FOR LADINIAN (MIDDLE TRIASSIC) PLATFORM PROGRADATION IN THE GYULAKESZI AREA, TAPOLCA BASIN, WESTERN HUNGARY: MICROFACIES ANALYSIS AND BIOSTRATIGRAPHY

A shallowing-upward carbonate sequence was studied from the outcrop at Gyulakeszi, Tapolca Basin (western Hungary), and it is interpreted as a Middle Triassic ( Curionii or younger) platform progradation. Two lithostratigraphic units are distinguished. Microfacies analysis and micropaleontological investigation conducted on the red nodular, cherty limestone (Vaszoly and Buchenstein formations) suggest that the lower unit was deposited during the Reitzi and the Secedensis ammonoid zones. The overlying white platform limestone (upper unit) is typical of a prograding platform and includes gravity-driven deposits at the base followed by periplatform facies deposited in shallow marine warm waters around the fair-weather wave base. The section at Gyulakeszi was unaffected by fabric-destructive dolomitization, which is uncharacteristic of similar platform facies in the Balaton Highland. Isopachous and radiaxial fibrous calcite cement found in the grainstone and boundstone facies are indicative of early lithification and diagenesis in the marine phreatic zone. “Evinospongiae”-type cement is described for the first time from the Balaton Highland and it is similar to the outer platform cements published previously from the Alps (Italy and Austria). The progradation could have advanced over the pelagic limestones as early as the Curionii zone, which is an undocumented event in the Veszprem Plateau. Similar event, however, is well known from the Western Dolomites, where aggradation was followed by intense progradation during the Gredleri and Archelaus ammonoid zones. The length of this progradation event at Gyulakeszi, however, is ambiguous since proven Ladinian (Longobardian) rocks are not exposed in the study area and were not penetrated by boreholes in the Tapolca Basin.