Quantification of the scale of Miocene extension in the Danube Basin based on 2D balancing
Authors: Váradi Kitti , Fodor László , Szijártó Márk , Bereczki László 
Published: February 2023

The Danube Basin is a prominent sub-basin of the Pannonian Basin, forming a transitional zone of the Eastern Alps and the Western Carpathians on the border of Slovakia, Hungary, and Austria. During the Miocene, the lithosphere of the Pannonian Basin underwent extensive rifting, leading to the formation of the Danube Basin (Tari, 1994). During this process, several grabens and half-grabens were opened, the timing of which has been investigated by previous studies (Tari et al., 2020; &#352;ujan et al., 2021; V&#225;radi and Bereczki, 2022) in both the Slovakian, the Austrian and the Hungarian part of the Basin.The aim of this research was to quantify the extension that took place in the Danube Basin during the Miocene. Using seismic sections crossing the particular grabens which were interpreted in previous research (V&#225;radi and Bereczki, 2022), we carried out 2D balancing of the sections, which is an area-preserving structural modeling method used for the reconstruction of the status of the geological layers before its deformations.With the outcome of this research, we were able to define the scale of the horizontal lengthening along the sections in meters and percentages, thereby giving an estimation of the scale of the stretching of the upper crust suffered in the study area during the Miocene rifting. Based on the preliminary results, the scale of the extension can be estimated at approximately 20&#173;&#8211;40%. This value is in line with the results of Bereczki et al. (2018), and can be compared with the results of Lenkey (1999) and Horv&#225;th (2007). In the future, our result can be refined by integrating balanced outcrop sections and by 3D balancing for the entire area.The research was supported by the National Research, Fund of Hungary (NKFIH) OTKA in framework of projects No. PD 142660 and No. 134873.&#160;References:Bereczki, L., G. Markos, D. G&#228;rtner, Z. Friedl, B. Musitz, B. Sz&#233;kely, and G. Maros, 2018, Structural modelling of some synrift sub-basins in the Pannonian Basin: EGU General Assembly Conference Abstracts, 13144.Horv&#225;th, F., 2007, A Pannon-medence geodinamik&#225;ja - Eszmet&#246;rt&#233;neti tanulm&#225;ny &#233;s geofizikai szint&#233;zis. Dissertation, E&#246;tv&#246;s Lor&#225;nd University, 240 p.Lenkey, L., 1999, Geothermics of the Pannonian basin and its bearing on the tectonics of basin evolution. PhD Thesis, Vrije University, Amsterdam, 215 p.&#352;ujan, M., S. Ryb&#225;r, M. Kov&#225;&#269;, M. Bielik, D. Majcin, J. Min&#225;r, D. Pla&#353;ienka, P. Nov&#225;kov&#225;, and J. Kotulov&#225;, 2021, The polyphase rifting and inversion of the Danube Basin revised: Global and Planetary Change, 196, 103375.Tari, G., 1994, Alpine tectonics of the Pannonian basin. PhD Thesis, Rice University, Houston (Texas), 510 p.Tari, G. C., I. Gjerazi, and B. Grasemann, 2020, Interpretation of vintage 2D seismic reflection data along the Austrian-Hungarian border: Subsurface expression of the Rechnitz metamorphic core complex: Interpretation, 8, SQ73&#8211;SQ91.V&#225;radi, K., and L. Bereczki, 2022, The polyphase Miocene extensional formation of the Hungarian and Slovakian part of the Danube Basin: Young Researchers in Structural Geology and Tectonics (Yorsget) 2022 Abstract Book, 37.