Magnetic mineralogy and paleomagnetism of serpentinized ultramafic rocks from the Braszowice–Brzeźnica fragment of Sudetic paleozoic ophiolite

• Autorzy: Kądziałko-Hofmokl M. , Jeleńska M. , Delura K. , Bylina P.
• Języki publikacji: EN

Abstrakty

EN

Complex paleomagnetic, rock-magnetic and mineralogical studies were performed on serpentinized utramafic rocks from Braszowice– Brzeźnica massif (BB) situated at the southern extremity of the Niemcza Shear Zone, close to the Sudetic Marginal Fault. Studies of magnetic minerals revealed presence of several varieties of magnetite grains, and partly altered Cr-spinels. Paleomagnetic studies revealed stable component HS of natural remanence carried by magnetite formed probably during the initial serpentinization. The directions of HS have good grouping within each locality, but differ between localities. Studies of anisotropy of magnetic susceptibility (AMS) have shown that directions of anisotropy axes are steep instead of horizontal as is common within the Niemcza Shear Zone. Taking advantage of the directions of AMS we rotated the directions of HS and brought them to the reference direction for the Sudetes for 372 Ma. We suggest that after acquiring AMS and HS during the Upper Devonian, the BB became divided into multiple units due to tectonic activity in the region.

Słowa kluczowe

EN

Sudetes; Paleozoic; ophiolite; tectonic rotations

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2010
• Tom: Vol. 58, no. 2
• Strony: 269--299
• Opis fizyczny: Bibliogr. 27 poz.

Twórcy

autor

Kądziałko-Hofmokl M.

autor

Jeleńska M.

autor

Delura K.

autor

Bylina P.

• 1Institute of Geophysics, Polish Academy of Sciences, Warsaw, Poland,

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