The first data on contents of trace and rare earth elements in leptitic rocks from the Złoty Stok-Skrzynka tectonic zone is given. They indicate that felsic volcaniclastic rocks such as tuffs or/and tuffites were the primary source materials for leptites. High contents of silica, potassium and sodium additionally confirm their derivation from rhyolitic protoliths possibly generated in a within plate palaeoenvironment.
Trace and REE element geochemistry of blastomylonites (known as the "Haniak gneisses") from north-western part of the Złoty Stok-Skrzynka Tectonic Zone (Eastern Sudetes) is reported for the first time. The obtained results indicate that source of primary material for blastomylonites might be the Gierałtów gneisses, the Śnieżnik gneisses or/and greywackes of the Stronie Unit. The enclaves of amphibolites included in blastomylonites display multielement profiles comparable with MORB-tholeiites or within-plate basalts, similarly as metabasites from the Śnieżnik-Orlica Dome. We suggest that the "Haniak gneisses" protolith represents a primary subcrustal granitic material which underwent progressive melting on different depth levels. We conclude that these processes were accompanied by enclosing of rock fragments derived from an earlier oceanic domain, probably along a suture zone.
This paper presents results of preliminary geochemical studies of ultrabasic rocks occurring in the eastern part of the metamorphic envelope of the Karkonosze granite intrusion. They fom two small, stock-shaped bodies within: 1) amphibolites (locality: popiel Hill, nearby Janowice Wielkie) and (2) amongst greenschists (locality: Niedamirów). obtained results indicate that theymay represent subduction-related cumulates formed in early stages of the fractional crystallisation of the ultrabasic melt. The lack of any deformational features in analysed rocks suggests their emplacement just after the main phase of regional metamorphism, which affected their host rocks. A Lower Carboniferous age of these intrusions and their closely relationship to an early volcanic activity recorded in sedimentary series of the Intrasudetic Basin also is postulated.
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