UPb zircon dating from some Variscan granites of the Central Western Carpathians (CWC) revealed the presence of relict zircons of Ediacaran/Cambrian age. Relict zircon crystals yielding an age of ~557 Ma with ɛHf(500) values (+9.6 to −5.5) are preserved in the Variscan tonalite aged ca. 353 Ma. Variscan magmatic ages in this tonalite show a narrower range of zircon ɛHf(350) values, from +4.0 to −2.2, suggesting that the granite protolith is a recycled Ediacaran/Cambrian magmatic source. Several relict zircon crystals with Cambrian ages of 535 and 527 Ma were also found in nearby Variscan granitic massifs dated to ~353 and ~ 351 Ma, respectively. Metaluminous diorite (~359 Ma) with a significant mantle signature having zircon ɛHf(350) = +8.3 to +0.2 is devoid of inherited zircons, while in the surrounding granodiorite, the relict zircon cores are ubiquitous. Variable proportions of crustal and mantle sources in the Variscan granites are indicated by Hf zircon isotopes and also from whole-rock ɛNd(350) values ranging from +1.6 to −5.9. Several Variscan zircons were detected in a peraluminous S-type metagranite with a high content of Ordovician relict zircons (~460 Ma, Cenerian orogeny), clearly providing evidence, supported by whole-rock geochemical analyses, of low-temperature partial melting of a Central Western Carpathian (CWC) crustal rocks during the Cenerian period. The preserved Ediacaran/Cambrian relict zircon crystals indicate rapid emplacement of Variscan granites driven by slab-breakoff geodynamics from the MASH (melting, assimilation, storage, homogenization) zone to the Ordovician and Upper Devonian wedge during a collisional Variscan granitic magmatism.

Detailed research on a small, isolated granite body, the so-called the Staré mesto granite (SMG), has yielded different information than are known from the main body of the Bratislava massif (Malé Karpaty Mts. in Western Carpathians, Slovakia). The SMG with a known gold mineralization is exposed as a small, elongated granite body hosted within the biotite gneisses of the Pezinok Group that are missing in the main Bratislava granite massif, because of a deeper erosion level. The high-potassium content, peraluminous and magnesium character of studied SMG granites are analogous to the evolved felsic members of the main granitic body. However, new dating results, i.e., a zircon U–Th–Pb isotopic age of 363.5 ± 2.1 Ma and a monazite chemical Th–U–Pb age of 360.7 ± 2.8 Ma are different from the magmatic age of ca. 355–353 Ma determined for the main granite body of the Bratislava massif. It is suggested that melting of the SMG granite source occurred during the initial stage of the Variscan continental collision before ca. 360 Ma, while the main granitic body of the Bratislava Massif was formed in the course of the late-collision granite flare-up before ca. 355–353 Ma.

A set of small iron oxide-apatite (IOA) ore bodies have been discovered within polydeformed and polymetamorphosed metasedimentary rocks on Prins Karls Forland, Svalbard. A complex tectonothermal history resulted in the development of various ore structure, varying from brecciated to mylonitised. Generally, the IOA ores are divided into two major geochemical subtypes: (1) fluorapatite-bearing with predominant low-Th monazite, and (2) F-Cl apatite-bearing with predominant high-Th monazite. Initial alteration of the ores resulted in liberation of REE and P from the apatite and redeposition as small (

Granite typology in terms of identification I- and S-types is based on granite composition and accessory mineral characteristics. Mixing of mafic and felsic melts during the formation of granite massifs can lead to non- equilibrium accessory paragenesis formed from mixture of typical I- type accessory pragenesis (Ti-magnetite, allanite, titanite, low Mn apatite) and S-type composed typically from monazite and high Mn apatite. The extensive mixing processes in the tectonically northern tilted Krivan Fatra granite massif, where the tonalite zone is situated below granodiorite, provide evidences for the formation of non-equilibrium accessory paragenesises by two recognisable stages. The first stage, a deep crustal mixing of the mafic melts into the formed felsic magmatic chamber is indicated in presence of 1) relic plagioclase P1 (An33-37 and An40-56); 2) quartz with rutile needles; 3) quartz ocelli surrounded by trioctahedral micas; 4) inclusions of pyroxene and V, Cr relic mineral phases in an accessory pyrite. Quartz antecryst with rutile rods, antiperthitic plagioclase, and Ti-magnetite disintegration at 780 degrees C indicates a high temperature mixing in the low crustal MASH zone. High portion of the apatite was probably late in the early stage transformed to monazite by fluids from early magmatic allanite(Ce) giving an evolved sulphur content to this monazite. The second stage occurred in crustal conditions when the melt-mixing continued by convectional homogenization of initial mixed magma forming oscillatory-zoned plagioclases P2 (An32-20), Ba and Na is high in K-feldspar giving a hybrid character of the Krivan Fatra granodiorites. The late mixing stage effectively is indicated by abundant apatite with composite chemistry partly I-type (low Mn, Fe but high S, Cl) and partly S-type (high Mn, and LREEs). Apatite formation temperatures in the tonalite zone is 792 degrees C, and in the granodiorite zone is between 780 and 819 degrees C pointing to the evolution pathway from the inhomogeneous mixed granotonalite to relatively homogenous granotonalite in the granodiorite zone. The positional upper granodiorite zone with the transitional granite typology in the Krivan Fatra granite massif resulted from high degree of magma mixing of former mafic gabbro (?) and felsic melt forming the non-equilibrium accessory paragenesis, as S-/I-type apatite mixture composition. In general view, not well homogenized granitic parts recognised in the upper north granodiorite zone of the Krivan Fatra granite massif can be typologically defined according to Castro (2001) as a transitional mixed granotonalite.

A general timing of the & Scaron;tiavnica Stratovolcano edifice evolution based on structural relationships, biostratigraphic data and previous dating by K/Ar and Rb/Sr methods could not resolve more exactly the critical interval of the subvolcanic intrusive complexes emplacement, a caldera subsidence and evolution of related mineralizations. To fill the gap we have carried out 20 precise SHRIMP U-Th-Pb zircon datings of relevant intrusive and volcanic rocks as well as K/Ar dating of illite and adularia and Re/Os dating of gold and sulfides from a related epithermal mineralization. Their high precision allowed to recognize a succession of subvolcanic intrusions concluded by the caldera collapse and to establish age of the B. Hodru & scaron;a precious/base metal epithermal mineralization. Based on new interpreted age intervals for individual stages and sub-stages in a complex evolution of the & Scaron;tiavnica Stratovolcano edifice we update the scheme of its evolution as follows: (1) construction of an extensive and complex andesite stratovolcanic edifice during the interval 15.0-13.6 Ma, including emplacement of a diorite intrusion around 14.8 Ma and emplacement of a diorite porphyry stock at Beluj 14.5 Ma; (2) emplacement of subvolcanic intrusive rocks including: emplacement of rare quartz-diorite porphyry sills pre-dating the B. Hodru & scaron;a epithermal mineralization around 13.6 Ma; emplacement of the granodiorite bell-jar pluton around 13.44 Ma; granodiorite pluton resurgent uplift, sector collapse and related evolution of the B. Hodru & scaron;a epithermal mineralization in the interval of ca. 13.44-13.31 Ma; emplacement of quartz-diorite sills in the shear zone that post-date the epithermal mineralization around 13.31 Ma; emplacement of other quartz-diorite porphyry sills and ring dikes during the interval of ca. 13.3-13.0 Ma; emplacement of granodiorite porphyry stocks and dike clusters around 12.9 Ma; (3) subsidence of the caldera and its filling by evolved andesites around 12.9 Ma; (4) renewed activity of less evolved and mixed type andesites during the interval of ca. 12.8-12.3 Ma; (5) uplift of the resurgent horst in the central part of the caldera accompanied by rhyolite volcanic/intrusive activity between 12.3 and 11.4 Ma.

One of the key areas in Bulgaria for studying the late Carboniferous to Permian igneous events related to the last episodes of the geodynamic evolution of the Variscan orogeny is the basement of Central Sredna Gora Zone. The current research is focused on the Smilovene and Hisarya plutons (with I-type affinity), and the subsequent Strelcha pluton (with S-type affinity) formed in the refined interval of 305 Ma to ~294 Ma. The I-type granodiorite-dominated Smilovene and Hisarya plutons show many indicators of magma mixing and mingling processes as well as typical to the I-type granites accessory minerals (e.g., titanite, low-Mn apatite, zircon, and typical zonal allanite-(Ce)). This magmatic activity ended with the emplacement of S-type muscovite granites (Strelcha type granites), where mafic input practically is absent. The typical accessory minerals are apatite, zircon, and monazite, while allanite-(Ce) is observed only as a product of monazite breakdown. A striking feature is the monazite breakdown into an apatite-allanite-(Ce)-clinozoisite corona, the driving force of which is attributed to the Early Alpine tectonic activity.

This paper reports the first finding of oriented triphylite (LiFe2+PO4) rods in fluorapatite. This observation was made in the contact zone between a metamorphosed rare-element pegmatite and its amphibolite wall rock at the Stankuvatske Li-ore deposit in the Ukrainian Shield. This contact zone consists of an exocontact, in which hornblende was altered to biotite, and an endocontact, which comprises four parallel mineral zones (aplitic, apatite, triphylite, and transitional).The needle-shaped triphylite inclusions were observed in greenish-blue apatite within the apatite zone. They are oriented parallel to structural nanochannels along the c-axis in apatite and were formed due to the infiltration of Li-rich, pegmatite-derived fluids into the apatite zone. Small amounts of pyrite, U-Th-rich and Fe-rich phases, as well as small mono-phase fluid inclusions of CO2, CO, and N2 are associated with the oriented triphylite inclusions and record the character of fluid.The exo- and endocontacts were formed as a result of interaction between metasomatic fluids derived from the pegmatite (enriched in K, Na, Li, Rb, F, P, and Mn) with the host amphibolite. At the contact, the amphibolite was altered into the biotite zone during the first metasomatic stage; alteration of hornblende and plagioclase released Ca, Fe, and Mg toward the pegmatite, where these elements reacted with P, Li, and Mn to produce the apatite and triphylite zones during the second metasomatic stage. Acting like a geochemical barrier, the apatite zone in the endocontact inhibited the further escape of Li from the pegmatite, which now is a Li-ore deposit. The metasomatic processes observed in the Stankuvatske Li-ore deposit represent an example of apatite and triphylite formation at the contact between a pegmatite and a metabasite, which has metallogenetic implications.

The Permian S-type granites in the Gemeric Unit of the Western Carpathians have no analogues in the basement of the nearby Eastern Alps and Bohemian Massif. Their initial position should be searched in the south and southwest before the large Tertiary eastward shifting of the Western Carpathians along with Alps and Pannonian within the ALCAPA megaunit. The age, specific crustal character, metallogeny of the Gemeric granites prompt regional-scale search of granite analogy with close in age, geochemistry and metallogeny in other fragments of the Variscan orogen elsewhere in Europe and North Africa (e.g. Marocco, West Europe, Balkans). A possible origin of Gemeric granites on continental arc is presented and discussed.

This study presents petrological, geochemical, geochronological and structural data that serve to identify two different Alpine tectonic units formed from the Variscan-aged Tribec-Zobor granitic rocks. The proposed model for juxtaposition of two granite blocks in the Tribec-Zobor basement during the Alpine orogeny is based on the degree of granite alteration, particularly related to differences in monazite stabilities of the S-type granitic rocks along the studied NW- SE profile through the Tribec-Zobor mountain range. Along the cross-section, the Variscan crystalline basement in the mountain crest is composed of hydrothermally altered and metamorphosed S-type monzogranite (zircon age: 355.2 +/- 1.2 Ma). Below this monzogranite there are hypidiomorphic non-altered granitic rocks with ages spanning from 357.8 +/- 0.66 Ma to 351.2 +/- 0.7 Ma for northeast S-type and 358.2 +/- 0.85 Ma to 347.9 +/- 0.94 Ma for I-type on southwest part of profile. U-Th-Pb dating revealed both low- and high-Y types of monazite in the S-type granites. Low-Y monazite from both the structurally lower unaltered, and the structurally upper, metamorphosed S-type granitic rocks provides Tournaisian Variscan ages in the range of 354-349 Ma. The high-Y monazite from the same rocks records Visean ages in the range of 348-335 Ma, likely indicating later-staged thermal rock overprinting. Monazites from non-altered S-type granodiorites are stable due to rapid emplacement in the upper crustal position. In contrast, the monazites in the overlying metamorphosed Stype granites are retrogressed to allanite as a result of slower, nearly isobaric cooling of the granites emplaced at deeper crustal levels. Thus, monazite behaviour indicate two different Variscan granite blocks, similar in age but with different emplacement depths. The conditions for metamorphism (450-500 degrees C, 750-800 MPa) of the structurally upper granites are inferred from phase equilibrium thermodynamic modelling, occurring during the Alpine orogeny. These metamorphic conditions are similar to those calculated for granites of the Western Carpathians that were pervasively reworked during Alpine orogenesis, indicating that structurally upper granites have an affinity to the Alpine Fatric Unit, whereas the lower granite is rather related to the Tatric Unit. An Alpine date of c. 78 Ma yielded by single grain fusion 40Ar/39Ar geochronology of muscovite is interpreted to post-date Alpine thrusting. The present position of the metamorphosed Variscan Fatric granitic rock in the Tribec-Zobor crystalline basement, overlying both S- and I- non-altered Tatric granites, resulted from large-scale, northdirected Alpine thrusting. The geometry of the thrust, elucidated by tectonic elements from mylonites and hydrothermally altered Triassic quartzites deposited on Fatric granites, is inclined 20-40. to the northwest.

The Variscan basement outcropping along the Iskar River Gorge and in the Botevgrad basin gives a perfect opportunity to study the entire late Carboniferous to early Permian magmatic episode including several stages. The initial stage of a K-alkaline magmatism at 330 to 310 Ma, which points to a melting of enriched mantle source, was followed by a voluminous calk-alkaline to K calk-alkaline magmatism and emplacement of several plutons in the interval between 309 and 306 Ma as well as volcanics (307.4 +/- 2.2 Ma). Coeval sporadic K-alkaline events are constrained as well. During the third stage, in the interval 288-286 Ma, an intrusion of predominantly acid subvolcanic bodies and dikes took place. After ca. 35 Ma long period of magmatic quiescence, a new episode of magmatic activity started at late Permian-Early Triassic when "A-type" magmatism specific to rifting setting was initiated. The same event is geochronologically proved further east in the Central Balkan and Sliven region (Sinite kamani).

Accessory columbite-(Fe) to tantalite-(Fe) from three granitic pegmatites of the Tatric Superunit (Bratislava Massif of the Male Karpaty Mts., Bojna Massif of the Povazsky Inovec Mts. and Suchy Massif of the Strazovske Mts.) was used for dating by the in-situ LA-ICP-MS U-Pb method. The columbite-tantalite crystals were sampled from the most fractionated pegmatite dykes of the beryl-columbite subtype situated in the pre-Alpine, Paleozoic crystalline basement of the Tatric Superunit, Western Carpathians (western and central Slovakia). The obtained columbite-tantalite Concordia ages are as follows: 354.5 +/- 4.5 Ma (Jezuitske Lesy pegmatite, the Bratislava granite Massif), 360 +/- 5.0 Ma (Moravany nad Vahom, Striebornica Ridge pegmatite, the Bojna Massif), and 352 +/- 8.5 Ma (Liestany, Bystry Hill pegmatite, the Suchy Massif). The columbite-tantalite ages show Mid-Variscan formation of rare-element pegmatites from the Devonian/Carboniferous boundary to Tournaisian stage, which is coeval with the emplacement of cogenetic granites during the main phase of Variscan intracontinental subduction and collision. The obtained columbite-tantalite age interval of rare-element granitic pegmatites of the Tatric Superunit (similar to 360 to 350 Ma) is generally older than the ages of Be- and Li-rich rare-element pegmatites of the Moldanubian Superunit in the Bohemian Massif (similar to 340 to 320 Ma). The rare-element granitic pegmatites of the Austroalpine Superunit (Eastern Alps) are significantly younger (similar to 290 to 240 Ma) because they were formed in an extension regime during the Permian to Early Triassic post-Variscan orogenic collapse.

On Prins Karls Forland, Svalbard Archipelago, a set of small iron oxide-apatite (IOA) ore bodies have been discovered within a crustal shear zone, which deformed the polymetamorphosed Neoproterozoic metasedimentary rocks. The ores have various styles and grades of deformation and distinct mineral assemblages whose compositions record a multi-stage tectonothermal and metasomatic history. These IOA ore bodies can be subdivided into fluorapatite-bearing and predominant low-Th monazite in the upper section of the shear zone and F-Cl apatite-bearing and predominant high Th-monazite in the structurally lower higher-grade deformed part. The first stage of alteration for these ore bodies resulted in metasomatic alteration of the apatite and liberation of REE and P redeposited as monazite and xenotime. The transport of dissolved REE and P was likely enhanced by deformation. The second stage of alteration had a distinct impact on the individual ore bodies, which resulted in the Th-enrichment of a small subset of the monazite grains in the upper section of the shear zone. In the lower section of the shear zone most of the monazite was replaced by high Th monazite. Here the original fluorapatite is enriched in Cl, Mn, and Sr, most probably due to interaction with CaCl2-rich fluids enriched in Sr and Mn that was scavenged from the hosting metasediments and altered metagabbros. Contrasting textures, mineral assemblages, and the geochemistry of the ores from distinct localities reflect involvement of compositionally different fluids from the gabbroic rocks and surrounding metasedimentary rocks during the protracted tectonothermal evolution of Prins Karls Forland. Therefore, it is concluded that the IOA ore bodies most likely resulted due to the fractionation of Fe, P, Ca, and REE from hypersaline fluids associated with the gabbros. Once deposited, these IOA ore bodies were subsequently altered during at least one and perhaps two later metamorphic events.

The highly peraluminous Zamostska Hola leucogranite (ZHG) forms a small, dyke-like body within the granodiorites of the Prasiva type in the composite, 353-351 myr Low Tatra Pluton (LTP), Central Western Carpathians, Slovakia. The ZHG fabric recorded syn-magmatic brecciation, multiple influxes of fluid-rich melt, and fluid-rock interaction. The accessory mineral assemblage includes zircon, xenotime-(Y), monazite-(Ce) and allanite-(Ce). The zircon in the ZHG shows very low Zr/Hf and Th/U; apparently, primary zircon is euhedral, oscillatory zoned and P, Al, Ca, Fe, U, Y, HREE-rich; however, most of the zircon grains are to variable extents altered by dissolutionreprecipitation process, and show depletion or redistribution of trace elements within the crystal. The xenotime-(Y) is spatially associated with zircon and varies from the euhedral, igneous-like to strongly irregular secondary grains formed from the zircon dissolution in the presence of P-bearing fluid. Some zircon and xenotime-(Y) grains are high in As. The monazite-(Ce) shows morphology typical for early-magmatic origin, and alteration is restricted to huttonite-enriched, U, Ca, Y-depleted rims and patches; however, the entire crystals are unusually high in F up to 0.8 wt %. The monazite-(Ce), followed by the trace element-rich zircon and euhedral xenotime-(Y), crystallized from peraluminous, F, U, Y + HREE-enriched melt and resemble ones from highly fractionated granites or pegmatites. The alteration of primary accessory minerals and formation of the secondary xenotime-(Y) is related to an influx of alkali-enriched, fluid-dominated magma. The reaction of REE in fluid with brecciated and altered plagioclase and micas led to the local formation of secondary allanite-(Ce). The magmatic age of the ZHG monazite is 345 +/- 2.5 Ma and emphasizes its formation in the final stage of the prolonged evolution of the LTP; but whether the leucogranite represents residual differentiates of the magma of hosting Prasiva type, or independent magmatic pulses, remains an unresolved issue. The exceptional accessory phases assemblage records mineral-melt-fluid interactions in the late magmatic-hydrothermal transition, which is the critical ore-forming phase, and overall characteristics of the ZHG minerals shares attributes of those in the fertile intrusions and provides arguments for the close relationship between the composite magmatism and the ore petrogenesis in the LTP.

The Carpathian Mountains form the large collisional orocline stretching from Vienna, Austria to Bucharest, Romania. The Western and Inner Carpathians include the High Tatra mountains, which exhibit the highest elevation peaks of the entire mountain belt. Here we studied the exhumation history of an area near Gerlachovský štít, the topographically highest point of the High Tatras. Granitoid samples from different elevations were collected and analyzed for apatite (U-Th)/He (n=12; 5-6 aliquots) and zircon (U-Th)/He ages (n=22; 2-4 aliquots). In addition, apatite U-Pb dating by LA-ICPMS was conducted to complement existing zircon U-Pb dates to track the evolution of the High Tatra Mountains from the onset of magmatism during the Variscan orogeny. The (U-Th)/He apatite ages show a general increase from 9.6 ± 0.6 Ma to 31.9 ± 2.0 Ma to from lower to higher elevations. The zircon (U-Th)/He ages are more scattered and range from 13.5 ± 1.1 Ma to 47.8 ± 3.9 Ma. These reported ages agree with published low-temperature thermochronometric results. However, the apparent average exhumation rates for zircon and apatite (U-Th)/He data derived from the age-to-elevation profile near Gerlachovský štít are inconsistent with a proposed rapid early Miocene exhumation pulse. Apatite U-Pb ages obtained in this study are between 337.61 ± 2.21 Ma and 372.74 ± 3.09 Ma. These ages agree with previously reported zircon dates from the same or nearby samples. This observation is indicative of rapid cooling of the granitoids following crystallization. However, the greatest variance in both data sets were observed from samples collected near the sub-Tatra fault and along the Ružbachy fault. This observation was used to confine regions about these major structures that have distinct exhumation records. The results of the (U-Th)/He ages captures both pre- and post-Miocene slow cooling interrupted by early Miocene tectonic unroofing. Overall, these results are used to outline the earliest tectonic history of the High Tatra Mountains until the onset of more recent exhumation and impacts our understanding of the origin and development of this section of the arcuate mountain belt.

AbstractThe Palaeoproterozoic (~2.0−1.8 Ga) Stankuvatske Li deposit (Ukrainian Shield, Central Ukraine) represents an uncommon case of recrystallised, fine-grained petalite ± spodumene meta-pegmatite dykes with LCT affinity hosted in amphibolites and meta-ultrabasic rocks. The meta-pegmatite dykes show remnants of primary, pre-metamorphic zoning, with dominant magmatic albite, K-feldspar, quartz, Li-phases (petalite, spodumene, rarely triphylite and montebrasite), and accessory muscovite, fluorapatite, columbite-(Fe), tantalite-(Fe), cassiterite, Ta-rich rutile, zinco- and ferronigerite, gahnite, pyrite, sphalerite and zircon. The parental magma of the meta-pegmatites was peraluminous, and enriched in Li and P, though relatively poor in B and F during the late-magmatic stage. Metasomatic reactions between residual pegmatite magma and (ultra)basic country rocks resulted in the precipitation of holmquistite, triphylite, fluorapatite, tourmaline and Rb–Cs-rich biotite. Secondary generations of fine-grained petalite, spodumene, albite and K-feldspar were formed during post-magmatic stages, i.e. during hydrothermal–metasomatic alteration and/or subsequent tectono–metamorphic recrystallisation of the primary pegmatites. The initial subsolidus metasomatism of primary feldspars took place in alkaline conditions as a result of Na (partly K) for Li exchange.The presence of fibrolitic sillimanite and chrysoberyl, together with the scarcity of muscovite and (OH,F)-bearing minerals, point to metamorphic recrystallisation of the former Li-rich granitic pegmatites at relatively high-temperature and medium-pressure (~600±50°C; ~0.3−0.4 GPa) conditions.

The Western and High Tatra Mountains (northern Slovakia, southern Poland) contain the best-exposed rocks record within the Carpathian orogenic belt. Petrological, geochemical, and geochronological data from granitic assemblages across the Western (n = 1) and High Tatra Mountains (n = 19) were used to understand how they responded to an extended tectonic and magmatic history. Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) zircon dating shows a dominant Early Carboniferous (Tournaisian, TuffZirc age = 349.3 + 2.9 / -1.5 Ma at 95 % confidence, n = 119 spots), but Paleoproterozoic/Neoarchean (2544 +/- 33 Ma, +/- 1 sigma) to Late Carboniferous (Kasimovian, 305.8 +/- 6.2 Ma) dates were also found. The age pattern is consistent with granitic assemblages within the European Variscan belt and suggests an affinity with Armorican terranes derived from a northern Gondwanan Cadomian arc. The final stages of Variscan orogenic collapse are timed at ca. 315 Ma based on the youngest zircon age population. Monazite dated in thin section are also Tournaisian, but the youngest age is Permian (Th-Pb, 270.0 +/- 9.1 Ma, +/- 1 sigma), consistent with timing of large-scale Pangean Permian extension. High Tatra granite K-feldspar 40Ar/39Ar ages indicate slow post-magmatic cooling after granite crystallization. The oldest 40Ar/39Ar ages from two samples near LomnickATIN SMALL LETTER Y WITH ACUTE stit (LS) suggest a thermal event in the Late Triassic (similar to 220 Ma), but others from the sub-Tatra fault and near GerlachovskATIN SMALL LETTER Y WITH ACUTE stit (GS) are younger (Early Cretaceous, similar to 120 Ma). The thermal history from K-feldspar at the base of LS shows pulsed exhumation at faster rates between 70-55 Ma (300-200 degrees C) and 45-35 Ma (200-100 degrees C). The results document the Paleo-Alpine tectonic imprint of the Western and High Tatra Mountains until the onset of more Neo-Alpine exhumation. The data point to uplift earlier than suggested by models of extrusion tectonics applied to the region. Early uplift is connected with Eocene ALCAPA (ALps-CArpathians-PAnnonia) escape leading later to the development of the Carpathian arc.

The Variscan basement within the Western Carpathian Alpine architecture generally consists of metaluminous/peraluminous tonalite/granodiorite massifs and high-grade metamorphic complexes of metapelites, metaultramafites, and metabasites with relics of eclogites. Unfortunately, the Variscan crystalline basement of the Western Carpathians is only fragmentally exposed. Therefore, the proposed geodynamic evolutionary model for the Variscan granites of the Western Carpathians is primarily based on granite data from the Mala Fatra Mts. with additional dating from the High Tatra Mts. The oldest magmatic age of 362 +/- 4 Ma in the Mal ' a Fatra horst was recorded in diatexites from a high-grade metamorphic complex, which is related to crustal anatexis during Variscan subduction. Subsequent collisional event and break-off of the subducted slab promoted exhumation of the diatexites within the high grade metamorphic complex and intrusion of 353 +/- 3 Ma old Tournaisian tonalite. Intensive heat input after slab break-off from the rising asthenosphere generated melting of the lower crust and extensive calc-alkaline, Mg-rich granitic magmatism in a short time span from 347 +/- 4 to 342 +/- 3 Ma. These Visean granitic rocks caused thermal overprint on the roof metamorphic rocks, including diatexites and Tournaisian tonalites at ca. 348 +/- 5.6 to 342 +/- 3 Ma. The Visean granite formation was controlled by the mixing of hot magmas, which is indicated by the presence of composite oligoclase/andesine plagioclase with preserved labradorite cores, alkali feldspars with Na2O >= 2 wt%, zoned apatite, the presence of antiperthite, and quartz ocelli. Elevated contents of mantle-derived elements like V, Ni, Cr, Ba, high Sr/Y ratio of similar to 44, steep LREE and flat HREE segments of chondrite-normalised patterns document adakite-like feature of the investigated granitic rocks which resulted from melting of a mixed lower-crustal and mantle sources and crystallisation in the presence of garnet. Unusual abundance of Fe-Ti oxides in granodiorites with magmatic cooling temperatures of 735-756 degrees C supports high-T input from mantle. In the High Tatra Mts., diorite xenolith shows the age of 359.2 +/- 3 Ma, and its host granodiorite the age of 350.1 +/- 2.6 Ma. The diorite contains acicular zircons, which points to rapid exhumation. Stubby zircon of the host granodiorite shows regular, oscillatory zoning controlled by a gradual temperature decrease. The non-comagmatic relationships between diorite and host granodiorite are indicated also by a difference in zircon Th/U ratio, which is 0.2 for the host granodiorite, but 1.0 for the diorite on average. The presented data show that slab break-off could have been a mechanism that promoted Variscan granitic magmatism in the Western Carpathians.