Rock associations and petrogenesis of Indosinian alkaline complex of the North Hebei province, north China

摘要

The Indosinian alkaline complexes in northern Hebei Province are distributed along the two deep faults striking in an approximately east-west direction. These alkaline complexes are divided into three rock associations : (1) pyroxene diorite-quartz alkaline-feldspar syenite-alkali-feldspar granite-syenite- aegirine-augite syenite-alkali-feldspar granite; (2) pyroxenite-biotite pyroxenite-magnetite apatitic rock -syeite; (3) nepheline syenite-urtite-aegirine-augite syenite-ijolite. The former one occurs along the north deep fault, and the latter two aling the south deep one.