Origin and geodynamic relationships of the Late Miocene to Quaternary alkaline basalt volcanism in the Pannonian basin, eastern–central Europe

Abstract

14Alkaline basaltic volcanism has been taking place in the Carpathian-Pannonian Region 15 since 11 Ma and the last eruptions occurred only at 100-500 ka. It resulted in scattered low-16 magma volume volcanic fields located mostly at the margins of the Pannonian basin. Many of 17 the basalts have compositions close to those of the primitve magmas and therefore can be 18 used to constrain the conditions of the magma generation. Low degree (2-3%) melting could 19 occur in the convective asthenosphere within the garnet-spinel transition zone. Melting started 20 at about 100 km depth and continued usually up to the base of the lithosphere. Thus, the final 21 melting pressure could indicate the ambient lithosphere-asthenosphere boundary. The 22 asthenospheric mantle source regions of the basalts were heterogeneous, presumably in small 23 scale, and included either some water or pyroxenite/eclogite lithology in addition to the fertile 24 to slightly depleted peridotite. Based on the prevailing estimated mantle potential temperature 25 This is reinforced by the detected low-velocity seismic anomalies in the upper mantle beneath 37 the volcanic fields. 38 39Manuscript Click here to download Manuscript: IJES_paper_2014_rev.docx Click here to view linked

Helium and carbon isotope signatures of gas exhalations in the westernmost part of the Pannonian Basin (SE Austria/NE Slovenia): Evidence for active lithospheric mantle degassing

“…It was followed by an upper Miocene to lower Pliocene asthenospheric upwelling due to extreme lithospheric thinning, accompanied by eruption of andesites and high-Al basalts. Finally, alkaline mafic lavas erupted in the Pliocene and Quaternary (Konecny et al, 2002;Ali et al, 2013;Harangi et al, 2015;Horváth et al, 2015). Harangi et al (2015) explicitly exclude the existence of a mantle plume or plume fingers beneath the Pannonian Basin system.…”

Magmatic evolution of compositionally heterogeneous monogenetic Cenozoic Strzelin Volcanic Field (Fore-Sudetic Block, SW Poland)

“…The relative depletion in K in the Cenozoic volcanic rocks of CEVP is often attributed to the derivation of magmas from a metasomatized mantle source, containing a residual K-rich phase, such as amphibole, at the time of magma segregation (Lustrino and Wilson 2007, and references therein). On the other hand, the relative depletion in Pb, K and other LIL elements is also an inherent feature of the HIMU end-member, which is considered as a recycled oceanic crust, which suffered selective depletion in LIL elements due to dehydration during subduction (Willbold and Stracke 2006;Lustrino and Wilson 2007;Harangi et al 2015). A detailed discussion of these issues is beyond the scope of the current paper.…”

“…The Late Proterozoic-Early Palaeozoic protoliths of these crystalline rocks underwent deformation and metamorphism during the Variscan collision in Late Devonian to Carboniferous times (e.g., Oberc-Dziedzic et al 2005;Schulmann et al 2014, and references therein). The metamorphic rocks were intruded by granitic plutons of Carboniferous to Permian age (Kozłowski and Wiszniewska 2007;Oberc-Dziedzic et al 2013a, b, 2015 and references therein). The crystalline basement only partly crops out at the surface, being largely covered by up to a few hundred metres thick sedimentary cover, including Oligocene, Miocene and Pliocene sands and clays, overlain by Pleistocene tills, gravels, sands and loesses (e.g., Sawicki 1967).…”

AlpArray in Hungary: temporary and permanent seismological networks in the transition zone between the Eastern Alps and the Pannonian basin

“…Following the closure of these oceanic domains the Alcapa and Tisza-Dacia units gradually occupied the Carpathian Embayment from the late Oligocene until the late Miocene (11 Ma; Kázmér and Kovács 1985;Fodor et al 1999). The extrusion of these blocks overlapped with the intensive extension of the lithosphere in the central part of the CPR of which exact driving mechanism is still disputed (Huismans et al 2001;Horváth et al 2006;Kovács et al 2012;Harangi et al 2015;Balázs et al 2016). Alcapa and TiszaDacia eventually collided with the stable European platform in the late Miocene.…”

“…The main phase of the extension in the Miocene was accompanied by large scale calcalkaline volcanism in the vicinity of major tectonic zones (e.g. Mid-Hungarian Zone; Eastern Carpathian; Szabó et al 1992;Harangi et al 2007;Kovács and Szabó 2008); while alkaline basaltic volcanism occurred in the Plio-Pleistocene during the tectonic inversion stage (Embey-Isztin et al 1993;Harangi et al 2015) and produced sporadic volcanic fields in the CPR.…”