Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Acta Geologica Polonica

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Central Carpathian Palaeogene Basin

Sortuj według:

Ogranicz wyniki do:

The intramontane Orava Basin - evidence of large-scale Miocene to Quaternary sinistral wrenching in the Alpine-Carpathian-Pannonian area

Ludwiniak Mirosław, Śmigielski Michał, Kowalczyk Sebastian, Łoziński Maciej, Czarniecka Urszula, Lewińska Lena

Acta Geologica Polonica

2019

Vol. 69, no. 3

339--386

The Carpathian Orava Basin is a tectonic structure filled with Neogene and Quaternary deposits superimposed on the collision zone between the ALCAPA and European plates. Tectonic features of the south-eastern margin of the Orava Basin and the adjoining part of the fore-arc Central Carpathian Palaeogene Basin were studied. Field observations of mesoscopic structures, analyses of digital elevation models and geological maps, supplemented with electrical resistivity tomography surveys were performed. Particular attention was paid to joint network analysis. The NE-SW-trending Krowiarki and Hruštinka-Biela Orava sinistral fault zones were recognized as key tectonic features that influenced the Orava Basin development. They constitute the north-eastern part of a larger Mur-Mürz-Žilina fault system that separates the Western Carpathians from the Eastern Alps. The interaction of these sinistral fault zones with the older tectonic structures of the collision zone caused the initiation and further development of the Orava Basin as a strike-slip-related basin. The Krowiarki Fault Zone subdivides areas with a different deformation pattern within the sediments of the Central Carpathian Palaeogene Basin and was active at least from the time of cessation of its sedimentation in the early Miocene. Comparison of structural data with the recent tectonic stress field, earthquake focal mechanisms and GPS measurements allows us to conclude that the Krowiarki Fault Zone shows a stable general pattern of tectonic activity for more than the last 20 myr and is presently still active.

Late Eocene to Quaternary deformation and stress field evolution of the Orava region (Western Carpathians)

Peskova I., Vojtko R., Starek D., Sliva L.

Acta Geologica Polonica

2009

Vol. 59, no. 1

73-91

The northern part of theWestern Carpathians suffered polyphase deformation at the boundary between their Central and Outer parts. Palaeostress analysis in the Orava region revealed the existence of five different stress fields in the period from the Late Eocene to the Quaternary. The evolution of the stress fields was determined by detailed structural analysis of the fault slip and fold orientation data. The orientation of the stress fields shows an apparent clockwise rotation from the Late Eocene to the Quaternary. During the Late Eocene to Oligocene, E-W compression and perpendicular tension affected this area. This was the time when the Central Carpathian Palaeogene Basin formed. After this compression, the palaeostress field rotated approximatly 40-50[degrees], and NW-SE compression and NE-SW tension took place in the Early Miocene. The Middle Miocene to Pliocene was characterised by progressive rotation of the palaeostress field from NW-SE to the NE-SW direction of the maximum principal compressional stress axis ([sigma][1]). This clockwise rotation of the Oligocene to Quaternary palaeostress fields here is explained by the effect of the counterclockwise rotation of the ALCAPA microplate, and by the regional stress field changes in this region. The Quaternary stress field was reconstructed on the basis of structural measurements in the Pliocene sedimentary formations of the Orava-Nowy Targ Basin. The results of the palaeostress analysis show that the Quaternary stress field is characterised by E-W-oriented S[h] (minimum horizontal compression) and N-S-oriented S[H] (maximum horizontal compression).