Porównanie sekwencji deformacji fałdowych w północnej i południowej okrywie granitoidów Karkonoszy

Abstract

Comparison of fold deformation sequences in the northern and southern metamorphic cover of the Karkonosze granitoids.A b s t r a c t. We applied the detailed structural analysis to 394 outcrops in the southern and northern metamorphic cover of the Karkonosze Intrusion. We recognised five generations of fold structures: F1 – poorly preserved tight intrafoliation folds; F2 – the most common generation, with the whole variety of fold geometries, W–E and WSW–ENE-oriented fold axes in the northern contact zone, and W–E and WNW–ESE-oriented fold axes in the southern contact zone; F3 – chevron folds; F4 – kink folds observed only in the Stara Kamienica schist belt; and F5–wide open folds, locally transformed into monoclinal kink folds, probably formed during the Variscan intrusion of the Karkonosze pluton. Similarity observed in the structural style in the northern and southern contact zones prove that these lithostratigraphic units had formed a single unit – the Izera-Kowary Unit – and had undergone the same deformational stages before the Karkonosze granitoid intrusion took place.