浙东南楠溪江中下游地区火山岩地质特征及演化规律

GEOLOGICAL FEATURES AND EVOLUTIONARY REGULARITIES OF THE VOLCANIC ROCKS IN THE MIDDLE-LOWER REACHES OF NANXI RIVER IN SOUTH-EAST OF ZHEJIANG PROVINCE

楠溪江中下游地区发育大面积中生代火山-沉积岩系。可分为晚株罗世和早白垩世两个时代的不同火山岩系，其岩石化学、地球化学、同位素等均具不同的演化规律和模式，岩浆来源也有区别。粗安质或粗面质火山岩的发育可能是浙东南沿海白垩纪火山岩的一个特色。

A large area of Mesozoic volcanic-sedimentary rock series were developed in the middleolwer reaches of Nanxi River. They could be divided into two different rock series, i. e. the Upper Jurassic and the Lower Cretaceous, which had different evolutionary regularities and models for their petrochemistry, geochemistry and isotope etc. as well as different sources of their magma. The development of trachyandensitic or trachytic volcanic rocks may be a characteristic of the Cretaceous volcanic rocks at the castal areas of south eastern Zhejiang.