Paleogene retroarc flexural basin beneath the Neogene Pannonian Basin: A geodynamic model

Abstract:Recently shot 3D seismic data allowed for a detailed interpretation, aimed at the tectonic evolution of the central part of the Mid-Hungarian Shear Zone (MHZ). The MHZ acted as a NW vergent fold and thrust belt in the Late Oligocene. The intensity of shortening increased westwards, causing clockwise rotation of the western regions, relatively to the mildly deformed eastern areas. Blind thrusting and related folding in the MHZ continued in the Early Miocene. Thrusting and gentle folding in the MHZ partly continued in the earliest Pannonian, and was followed by sinistral movements in the whole MHZ, with maximal displacement along the Tóalmás zone. Late Pannonian inversion activated thrusts and generated transpressional movements along the Tóalmás zone.

Section: Stratigraphymentioning

confidence: 99%

Strike-slip reactivation of a Paleogene to Miocene fold and thrust belt along the central part of the Mid-Hungarian Shear Zone

Palotai¹,

Csontos²

2010

“…(Vass & Elečko 1982) which in the lowermost part contains kaolin clays from weathered crusts located in the north (Kraus 1989). This formation belongs to the retro-arc type Buda Basin (Tari et al 1993). …”

Section: Post-nappe Sedimentary and Volcanic Formationsmentioning

confidence: 99%

Geological evolution of the southwestern part of the Veporic Unit (Western Carpathians): based on fission track and morphotectonic data

Vojtko

Králiková

Andriessen³

et al. 2017

“…The largest such fault in the study area, the Darnó fault acted as a SE-dipping reverse fault creating a deep flexural sub-basin (Fig. 1b, Sztanó & Tari 1993;Tari et al 1993;Fodor et al 2005). In the study area, the Lower Miocene rock suites are mainly confined to the Darnó Zone where a small fault-controlled fan-delta (Darnó Conglomerate) was deposited at the eastern margin of NH-SSPB (Fig.…”

Section: Geological Backgroundmentioning

confidence: 99%

“…75 km to the SW of the study area (Palotai & Csontos 2010). Tari et al (1993) presumed that the Paleogene Basin was developed as a retroarc flexural basin by southward propagating backthrust along the northern margin of the NH-SSPB (North Hungarian-South Slovakian Paleogene Basin).…”

Section: Unauthenticatedmentioning

confidence: 99%

Cenozoic structural evolution of the southwestern Bükk Mts. and the southern part of the Darnó Deformation Belt (NE Hungary)

Petrik¹,

Beke²,

Fodor³

et al. 2016

Extensive structural field observations and seismic interpretation allowed us to delineate 7 deformation phases in the study area for the Cenozoic period. Phase D1 indicates NW-SE compression and perpendicular extension in the Late Oligocene-early Eggenburgian and it was responsible for the development of a wedge-shaped Paleogene sequence in front of north-westward propagating blind reverse faults. D2 is represented by E-W compression and perpendicular extension in the middle Eggenburgian-early Ottnangian. The D1 and D2 phases resulted in the erosion of Paleogene suites on elevated highs. Phase D2 was followed by a counterclockwise rotation, described in earlier publications. When considering the age of sediments deformed by the syn-sedimentary D3 deformation and preliminary geochronological ages of deformed volcanites the time of the first CCW rotation can be shifted slightly younger (~17-16.5 Ma) than previously thought (18.5-17.5 Ma). Another consequence of our new timing is that the extrusional tectonics of the ALCAPA unit, the D2 local phase, could also terminate somewhat later by 1 Myr. D4 shows NE-SW extension in the late Karpatian-Early Badenian creating NW-SE trending normal faults which connected the major NNE-SSW trending sinistral faults. The D5 and D6 phases are late syn-rift deformations indicating E-W extension and NW-SE extension, respectively. D5 indicates syn-sedimentary deformation in the Middle Badenian-early Sarmatian and caused the synsedimentary thickening of mid-Miocene suites along NNE-SSW trending transtensional faults. D5 postdates the second CCW rotation which can be bracketed between ~16-15 Ma. This timing is somewhat older than previously considered and is based on new geochronological dates of pyroclastite rocks which were not deformed by this phase. D6 was responsible for further deepening of half-grabens during the Sarmatian. D7 is post-tilt NNW-SSE extension and induced the deposition of the 700 m thick Pannonian wedge between 11.6-8.92 Ma in the southern part of the study area.