Premium
A Late Paleoproterozoic (1.80 Ga) subduction‐related mafic igneous suite from Lomza, NE Poland
Author(s) -
Krzemińska Ewa,
Williams Ian,
Wiszniewska Janina
Publication year - 2005
Publication title -
terra nova
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.353
H-Index - 89
eISSN - 1365-3121
pISSN - 0954-4879
DOI - 10.1111/j.1365-3121.2005.00631.x
Subject(s) - mafic , geology , geochemistry , subduction , magmatism , zircon , basement , continental arc , petrology , paleontology , tectonics , archaeology , history
The Lomza orthoamphibolites in the crystalline basement of NE Poland, dated at 1802 ± 9 Ma by SHRIMP zircon U–Pb, are characterized by high incompatible and REE element contents. These features, the low Nb, and the position of the rock compositions on La–Y–Nb, Zr–Nb/Zr and Zr–Nb–Y tectonomagmatic discrimination diagrams, suggest that the metavolcanics formed in a subduction setting, possibly within a continental margin island arc. The likely extension of the belt of Paleoproterozoic mafic magmatism from Latvia and Lithuania into NE Poland provides convincing evidence for the existence of an active plate margin in that region at that time.