Re-discussion on the origin of volcanic rocks of the Xinglonggou Formation, North China
再论兴隆沟组火山岩成因

Based on the composition and petrographic studies of the andesitic volcanic rocks of the Xinglonggou Formation in Beipiao region,western Liaoning Province,we found revisely-zoned and rhythmically-zoned orthopyroxenes as xenoerysts.The trace elemen abundances and patterns of the revisedly-zoned orthopyroxene xenocrysts indicate that the volcanic rocks of the Xinglonggou Formation wer the products of magma mixing rather than the lower-crust delamination.These orthopyroxenes perhaps came from the Early Mesozoi...