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海底火山活动区成矿热液流体来源长期存在争议。尽管海水来源说更为流行,但本文提供的下列证据表明,来自长英质岩浆的流体对冲绳海槽现代活动热水成矿系统有较大贡献:①冲绳海槽JADE热水区出现异常高热流,其下方1～2km处存在浅位长英质岩浆房;②CO_2、烃类、H_2等气体在热水成矿体系中极度富集甚至形成独立气流,与热水流体共存。气体的碳、氦同位素资料表明其来自长英质岩浆体系;③JADE成矿热水系统存在异常高温(330～392℃)和高盐度(6.7％～7.5％)热流体端元;④热水蚀变岩具较高的δ~(18)O组成(12.3‰～14.7‰),据热液石英δ~(18)O和流体充填温度估算的初始流体δ~(18)O组成与岩浆水相当。
Submarine volcanic active metallogenic hydrothermal fluid sources have long been controversial. Although the source of seawater is said to be more prevalent, the following evidence provided in this paper shows that the fluid from the magma in the Lower Cretaceous contributes significantly to the modern activity of the hot-water mineralization system in the Okinawa Trough: ① unusually high JADE hot water area in the Okinawa Trough In the heat flow, there is a shallow feldslian magmatic chamber at 1 ~ 2 km below. ②CO_2, hydrocarbons, H_2 and other gases are extremely enriched and even form independent air currents in hot metallogenic system, coexisting with hot water fluid. The carbon and helium isotope data of gas indicate that they originate from the magmatic system of the Chang-Ying magmatism. (3) The JADE ore-forming hydrothermal system is characterized by abnormally high temperature (330-392 ℃) and high salinity (6.7-7.5% The δ 18 O composition (12.3 ‰ ~ 14.7 ‰) of the altered rocks is high, and the δ 18 O composition of the initial fluid estimated from the δ 18 O and the fluid filling temperature of hydrothermal quartz and magmatic water quite.