Dávid Karátson

Eötvös Loránd University · Department of Physical Geography

Voluminous Miocene silicic volcanism sourced mainly from the extensional Pannonian Basin played a major role in the evolution of Central Paratethys. Here, we identify a widely distributed (> 3150 km ² ) member of the Upper Rhyolite Tuff, called the Dobi Ignimbrite, with a precise sanidine/plagioclase ⁴⁰ Ar/ ³⁹ Ar age of 13.064 ± 0.065 Ma (~ Badenia...

Nineteen Middle Miocene (Badenian and Sarmatian) microvertebrate faunas were collected by the first author in quantities of several tons of samples in the Northern Hungary region and from the Visegrád Mountains in Transdanubia over the last two decades. Sample materials were washed and sieved using the sieve system of Daams & Freudenthal (1988). Th...

Classic scoria cone morphometric research began in the first half of the 20th century: field surveys and various resolution maps provided its basis. With the advent of new imaging technology, new processing tools were needed: nowadays, various analysis modules and plug-ins are becoming increasingly common in GIS software. The combination of digital...

Morphometric studies of scoria cones have a long history in research. Their geometry and shape are believed to be related to evolution by erosion after their formation, and hence the morphometric parameters are supposed to be related with age. We analysed 501 scoria cones of four volcanic fields: San Francisco Volcanic Field (Arizona, USA), Chaîne...

Units with extremely variable erodibility are typical in the succession of pyroclastic-dominated volcanic fields. Welded ignimbrites are usually resistant to erosion, thus, they often appear as positive landforms, i.e., mesas or tilted plateaus after millions of years of denudation. The Bükkalja Volcanic Area being part of the most extended foothil...

During Earth’s history, geosphere-biosphere interactions were often determined by momentary, catastrophic changes such as large explosive volcanic eruptions. The Miocene ignimbrite flare-up in the Pannonian Basin, which is located along a complex convergent plate boundary between Europe and Africa, provides a superb example of this interaction. In...

We describe volcanic inverted relief sites around the world, making a comparative analysis of those most significant sites found from literature and our own search on imagery and global topographic maps. Over fifty significant areas of volcanic inverted relief were found. The comparative analysis is based on geoscience values defined by the main ge...

Székelyland in Transylvania (Romania) has few regions as unique as the Ciomadul (Csomád) Hills in their unparalleled beauty. Professionals have been researching this distinctive volcanic region for centuries. Earth scientists study the young volcanic cones, igneous rocks, mineral springs, and mofettas; limnologists probe the waters of Sf. Ana crate...

Ciomadul’s landscape represents an amalgamation of volcanic edifices that build up a lava dome complex. Spanning almost 1 million years of volcanic and geotectonic evolution, Ciomadul periodically released large amounts of volcaniclastic material that modified the local topography. The volcanic activity constrained the Olt River by carving the narr...

Ciomadul’s last explosive eruptions produced large volumes of pumice and ash, so-called tephra, which had the potential to be dispersed by wind over wide areas and deposited in geological archives (e.g., lakes and ocean floors). Using the chemical fingerprinting of volcanic glass in tephra deposits, at least four main eruptive events can be disting...

Lake Sf. Ana at the top of Ciomadul volcano is one of the only open water crater lakes in the Carpathian Mountains, and has been providing a habitat to bacteria, algae, and microscopic animals in the pelagic zone, as well as rich lakeshore wildlife for 27,000 thousand years. The water of the lake is considered to be clean even today, although plent...

Ciomadul (Csomád) is the youngest volcano in the Carpathians and the Carpatho-Pannonian Region whose latest eruptions may have been witnessed by Palaeolithic people. It is the only volcano in the region where, although with little probability, future eruptions may occur. Ciomadul was a lava dome complex, and its volcanic activity included both effu...

Structural hydroxyl content of volcanic quartz phenocrysts was investigated with unpolarized Fourier-transform infrared spectroscopy. The phenocrysts originated from five pyroclastic fallout deposits from the Bükk Foreland Volcanic Area (BFVA), Hungary, and two from the AD 1314 Kaharoa eruption (KH eruption), Okataina Volcanic Complex (Taupo Volcan...

Scoria cones are favorite targets of morphometric research. However, in-depth, DTM-based studies have appeared only recently, and new methods are being developed. This study provides a classic evaluation of the cones of Chaîne des Puys (Auvergne, France) as well as introduces a more detailed and statistics-based set of properties. Beside the classi...

Detailed investigation of a Lower Miocene Plinian pyroclastic sequence that crops out in the Bükk Foreland Volcanic Area (BFVA) in Northern Hungary is presented here. The studied eruptive products are part of a ca. 50 metres thick pyroclastic succession comprising of a basal ignimbrite that is covered by stratified pyroclastic unit including a topm...

Valószínűleg nincs olyan magyar ember, aki ne ismerné fel bárhol, bármikor a Badacsony sziluettjét. A Balaton partján sétálva, vagy egy hajó fedélzetéről nézve mindenki százszor, sőt ezerszer megcso-dálta már a Balaton-felvidék bazaltvulkánjainak jól ismert, jellegzetes formáit. Nincs ezzel másképp a kutató sem: a környék első természet-tudományos...

The Danakil Depression, located in the northern segment of the Afar rift, is a world-class example of active rifting and the birth of a new ocean. The unique, yet only partially interpreted geothermal system of Dallol in northern Danakil is currently receiving renewed attention by researchers and visitors despite its extreme climate since the recen...

The East Carpathian volcanic range experienced an along-arc, Late Miocene to Quaternary migration of eruptive activity during its ~11 Ma-long activity. Here, a novel and complex methodology is presented that yields new geochronological and geomorphological constraints on the evolution of the 20 volcanic edifices. New unspiked KAr ages either constr...

A Middle Miocene, ~8 m thick pyroclastic succession, reported from the Bükk Foreland Volcanic Area (BFVA) in Northern Hungary (Central Europe) specified here as the Jató Member, was produced by silicic phreatomagmatism (Phreatoplinian sensu lato). Two well-preserved outcrops ~8 km apart and inferred to be within ~10–50 km from source represent the...

In sprawling urban areas, geoheritage is suppressed into limited niches. Potential geosites are highly vulnerable and could disappear completely during construction, or their integrity could be irreversibly modified. Here, we create an inventory of urban geoheritage for Clermont-Ferrand in France, recording more than 50 sites using the French natio...

One of the best known places on Earth where volcanology meets archaeology and history is the volcanic island of Santorini (Thíra), Greece. It is famous for the cataclysmic Late Bronze Age (Minoan) Plinian eruption which destroyed the Minoan culture that flourished on the island. Hosting a central, flooded caldera bay and, within that, the active is...

We present a new model for the formation of Plio-Pleistocene alkaline basalts in the central part of the Carpathian-Pannonian region (CPR). Based on the structural hydroxyl content of clinopyroxene megacrysts, the 'water' content of their host basalts is 2.0-2.5 wt.%, typical for island arc basalts. Likewise, the source region of the host basalts i...

This study, which builds on high-precision unspiked Cassignol-Gillot K-Ar age determinations, presents an advanced DEM-based volumetrical analysis to infer long-term magma output rates for the Late Quaternary Ciomadul (Csomád) dacitic lava dome complex (East Carpathians, Romania). The volcanic field of Ciomadul developed on the erosional surface of...

Located at the southern tip of the Intra-Carpathian Volcanic Range in Romania, and composed of a dozen dacitic lava domes, the Ciomadul (Csomád) volcanic complex is the youngest eruptive centre of the Carpatho-Pannonian Region. Whereas, in the last decade, the explosive history of Ciomadul since 50 ka has been well constrained by numerous studies,...

The past decade has seen a great number of studies dealing with magmatic water contents and how these could be retrieved by the nominally anhydrous minerals' (NAMs) trace structural hydroxyl (water) contents. Constraints have been made to magmatic hygrometry with clinopyroxene and plagioclase. Although results suggest that the method is more flexib...

During the Late Bronze Age, the island of Santorini had a semi-closed caldera harbour inherited from the 22 ka Cape Riva Plinian eruption, and a central island referred to as ‘Pre-Kameni’ after the present-day Kameni Islands. Here, the size and age of the intracaldera island prior to the Late Bronze Age (Minoan) eruption are constrained using a pho...

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 fe...

Reconstructing ‘Atlantis’, the Late Bronze Age island of Santorini

A Kárpát–Pannon régió " tercier " bazaltvulkanizmusának ere-dete mai napig a hazai kőzettani és geokémiai kutatások kihívá-sokkal teli kérdése (l. Szabó et al., 1992; Embey-Isztin et al., 1993; Seghedi et al., 2004; Harangi et al., 2015). A legfontosabb kérdés az, hogy mi okozza az olvadást a földköpenyben (legnagyobbrészt az asztenoszférában) és a...

Négy, nagy vastagságú bükkaljai ignimbrit kvarc fenokristály töredékeinek víztartalmát vizsgáltuk hat mintavételi helyről. Az ignimbritek horzsakőtartalmú piroklaszt sűrűség-ár üledékek, amelyek heves robbanásos kitörések során a kitörési felhő összeomló anyagából keletkező sűrűség-árból rakódnak le. Mivel ignimbritek kvarc fenokristályain ezidáig...

Az illótartalom fontos tényező a magmák fizikai-kémiai tulaj-donságainak kialakulásában, pl. ásványi összetételét, sűrűsé-gét, viszkozitását határozza meg. A vulkáni működés szempont-jából is fontosak a fenti jellemzők: az illógazdagabb magmák inkább explozív, az illószegényebbek inkább effuzív vulkáni kitöréseket produkálnak. Az illók közül a víz...

I Ig gn ni im mb br ri it t ö ös ss sz zl le et t a az z e eg gr ri i " " T Tu uf fa ak kő ő-b bá án ny yá áb ba an n " " Az egri " Tufakőbányában " egy tipikus kalderaformáló kitörés során létrejött piroklasztit-összlet tárul fel, amely a Bükkalja vulkáni terület egyik legidősebb képződménye (Capaccioni et al., 1995). A rétegsor egy 20 cm állandó...

Jelen kivonat módszertani ismertetés arról, miként lehet megbízható nyomelemkoncentrációkat kinyerni " in situ " lézer-ablációs ICP-MS elemzésekből. Alig több mint egy tucat iroda-lom van kőzetüvegek pontonkénti nyomelemzéséről. A fő prob-lémát a kőzetüveg " átlátszósága " , mérete és inhomogenitása okozza. Az átlátszó ásványokon vagy anyagokon (kő...

The Middle to Upper Palaeolithic transition is one of the crucial periods of change in the prehistory of Europe due to the full emergence, continent-wide, of modern human lithic technologies, and detrimental of Neanderthal survival. Knowledge about the transition is growing, however, the evidence for cultural and technological developments for the...

Since the early 2000s, the DTMs have been increasingly used for morphometric studies, especially in volcanolog-ical research. The most common volcanic edifices for GIS analysis are the monogenetic scoria cones, because they are relatively symmetrical forms. With high-resolution LiDAR data we studied cone parameters, such as aspect, area, cone and c...

Ignimbrite-hosted quartz phenocryst fragments contain much lower hydroxyl defect concentration than quartz in igneous rocks. Pre-eruptive and post-depositional loss of hydrogen were hypothesized as the main processes for lowering the initial magmatic concentrations of hydroxyl defects. The aim of this study was to examine the hydroxyl defect concen...

We present major element glass data and correlations for the ‘Roxolany Tephra’ − a so far geochemically unconstrained volcanic ash layer previously described in last glacial (Marine Isotope Stage 2) loess deposits of the Roxolany loess–palaeosol complex in south-west Ukraine. This exceptionally well-preserved, 2–3-cm-thick tephra layer is character...

Scoria cones are often studied using geomorphometric and traditional GIS methods, e.g. aspect, slope his-tograms, area, cone height/width ratio. In order to enhance the non-symmetric shape components in contrast to the conical forms, we used a new approach in our research: the polar coordinate transformation (PCT) introduced by Székely & Karátson (...

Geomorphometric analysis of the scoria cones of the San Francisco Volcanic Field using polar coordinate transformation

Hydroxyl defect concentrations of quartz phenocryst fragments from various rhyolitic pyroclastic density current deposits from the Bükk Foreland Volcanic Area, Hungary, were determined by using micro-FTIR spectrometry. In addition trace-element analysis and SEM cathodoluminescence imaging were performed on the same crystals. Hydroxyl defect-content...

Original volcanic edifices of two successive stages of Gran Canaria are reconstructed using a geomorphometric analysis of existent or restored paleosurfaces. In the reconstruction, surface fitting was applied preferably to planèzes (i.e. triangular facets of original volcano flanks) and quasi-planar surfaces, QPS (those occurring on planèzes, or sc...

A twofold fabric analysis by using photo-statistics on rock surfaces and low-field anisotropy of magnetic susceptibility (AMS) is presented, making it possible to infer paleoflow directions, which in turn helps to constrain the primary volcanic geomorphology of a deeply eroded mid-Miocene field (Keserűs Hill lava dome group, Visegrád Mountains, Nor...

The Danube Bend, a river curvature, called Visegrád Gorge in its deepest and narrowest part, is one of the most picturesque landscapes in Hungary. Its origin and relief evolution has been a long-standing problem in Hungarian earth sciences. A number of geomorphological theories have been put forward in explaining the valley with a U-shaped planform...

az MTA doktora, tanszékvezető egyetemi tanár, PhD, tudományos főmunkatárs, ELTE Természetföldrajzi Tanszék Keele University School of Physical dkarat@ludens.elte.hu and Geographical Sciences, Nagy-Britannia r.gertisser@keele.ac.uk Bevezetés Jáva szigete – a maga 140 millió lakosával – Földünk egyik legsűrűbben lakott területe. Népessége, kultúrája...

The Carpathian Mountains were one of the main mountain reserves of the boreal and cool temperate flora during the Last Glacial Maximum (LGM) in East-Central Europe. Previous studies demonstrated late glacial vegetation dynamics in this area; however, our knowledge on the LGM vegetation composition is limited due to the scarcity of suitable sediment...

Lacustrine sediments are excellent sources of palaeoenvironmental and palaeoclimatic information because they usually provide continuous and high-resolution records. In centraleastern Europe however lacustrine records that extend beyond the Holocene are rather sparse.Palaeomagnetic records from this region are also insufficiently explored, and usua...

Régi adósságot törleszt a szerző és az ELTE Eötvös Kiadó a Vulkanológia II. egyetemi tankönyv megjelentetésével. A Vulkanológia I. kötetben (1998) a vulkánosság lemeztektonikai háttere, a magma képződése és fő jellemzői, valamint a vulkáni működés folyamatai kaptak helyet. A II. kötet mindenekelőtt a tűzhányó-tevékenység által létrehozott vulkáni f...

Definition“Relatively large, long-lived constructional volcanic edifice, comprising lava and volcaniclastic products erupted from one or more vents…” (Davidson and de Silva 2000).NoteThe previous but still existent name “stratovolcano” implied alternating layers of lava and pyroclastic rocks. However, the more recent term “composite volcano” better...

Quasi-planar morphological surfaces may become dissected or degraded with time, but still retain original features related to their geologic-geomorphic origin. To decipher the information hidden in the relief, recognition of such features is required, possibly in an automated manner. In our study, using Shuttle Radar Topography Mission (SRTM) digit...

Directional fabric – in the sense of preferred grain alignment – of deposits from subaerial pyroclastic density currents (PDCs) are widely reported and are related to forces are acting just before the emplacement of the load from the mass flow. In this way, flow direction, source area and emplacement mode have successfully obtained by investigating...

The timing of Late Pleistocene volcanic activity of the Ciomadul (Csomád) dacitic lava dome complex, site of the youngest eruptions in the Carpathians, has been constrained by morphometric analysis and radiometric chronology. Peléan domes and asymmetric domes/coulées built up the volcano, including the central edifice that hosts the youngest twin c...

Volcán de Colima is the southernmost member of Colima Volcanic Complex (CVC), where several lateral collapses have occurred possibly with blasts like the Mt. St. Helens eruption. The most recent of these was a caldera forming event ~4300 yr B.P. Besides frequent Plinian-type eruptions, the sector collapse-linked debris avalanches are the greatest r...

RO-535600 Székelyudvarhely, Városháza tér 5. szám, Hargita megye, www.varoshaza.ro, offi ce@varoshaza.ro, tel.: 0266-218383, 0372-662900, fax: 0266-218032

The Western slope of the Central Andes between 22° and 17°S is characterized by large, quasi-planar landforms with tilted ignimbrite surfaces and overlying younger sedimentary deposits (e.g. Nazca, Oxaya, Huaylillas ignimbrites). These surfaces were only modified by tectonic uplift and tilting of the Western Cordillera preserving minor now fossiliz...

Volcanic evolution of the Ciomadul (Csomád) lava dome complex, site of the youngest (Late Pleistocene, late Marine Isotope Stage 3) eruptive activity in the Carpathians, has been studied by advanced morphometry and radiometric (U/Pb, U/He and 14C) geochronology. The volcano produced alternating effusive and intermittent explosive eruptions from ind...