Geochemistry and tectonic significance of late Paleoproterozoic A-type granites along the southern margin of the North China Craton.

ABSTRACT: The Longwangzhuang pluton is a typical example of Paleoproterozoic A-type granite intrusions at the southern margin of the North China Craton. This pluton is composed of arfvedsonite granite and minor aegirine-augite granites. Samples from both granite types display similar zircon U-Pb ages with ²⁰⁷U-²⁰⁶Pb ages of 1612 ± 19 Ma [mean square weighted deviation (MSWD) = 0.66] and 1609 ± 24 Ma (MSWD = 0.5), respectively. The granites exhibit similar high silica (SiO₂ = 71.1-73.4 wt.%), high alkaline (Na₂O + K₂O = 8.10-9.26 wt.%, K₂O/Na₂O > 1), and low Al₂O₃ (11.8-12.8 wt. %) contents and metaluminous to weakly peraluminous bulk chemistry. The chemical variations of the Longwangzhuang pluton sugge

SUBMITTER: Wang Y 

PROVIDER: S-EPMC6952446 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature