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本文根据冲绳海槽的地下结构、地温场特征、以及浮岩中斑晶矿物的结晶温度和榴辉岩的熔融相关系等，综合分析了冲绳海槽酸性浮岩岩浆的活动模式。提出：在冲绳海槽中部和东部地下１５ｋｍ以下的地幔物质部分熔融，产生橄榄拉斑玄武质岩浆，而在海槽中部地壳下结构层中（７—１５ｋｍ）物质部分熔融产生少量安山质岩浆。因此，在冲绳海槽地下存在有双层岩浆房结构，并且二者之间在中部有岩浆通道。来自地幔的拉斑玄武质岩浆在下部地壳中一方面受到地壳物质的混染，另一方面早期结晶的基性矿物会发生部分熔蚀。与此同时，还会有新的结晶作用。在岩浆中将同时存在有三种结晶相：一是自地幔中带入的地幔物质结晶相，其８７Ｓｒ／８６Ｓｒ比值低（０．７０４左右）；二是地壳物质熔融残余物或由地壳岩浆中结晶的矿物，其物源为地壳，８７Ｓｒ／８６Ｓｒ比值高（０．７０９左右）；还有一种矿物是地幔岩浆受地壳物质混染后的产物，其８７Ｓｒ／８６Ｓｒ比值中等。岩浆在一个较长时间稳定的环境中（应该对应于冲绳海槽的扩张间隙）发生充分的结晶分异作用而变成富含ＳｉＯ２的酸性岩浆（浮岩岩浆）。
Based on the characteristics of the underground structure and geotemperature field in the Okinawa Trough and the crystallization temperature of the plagioclase minerals in the Okinawa Trough and the melting facies of the eclogite, the activity patterns of the acidic pluton magmatism in the Okinawa Trough are analyzed. It is proposed that the mantle materials below 15km underground in the center and east of the Okinawa Trough partly melt and produce olive tholei basaltic magma, whereas some (7-15km) material in the crust beneath the trough subsides to produce a small amount of andesite magma . Therefore, there is a double-layered magma chamber structure beneath the Okinawa Trough, with magma passages in the middle between the two. Lectra from the mantle of basalt magma in the lower crust on the one hand by the crustal material contamination, on the other hand early crystallization of the basic minerals will be partial corrosion. At the same time, there will be new crystallization. There are three kinds of crystalline phases in the magma: one is the mantle material crystalline phase brought into the mantle, the 87Sr / 86Sr ratio is low (about 0.704); the second is the crustal material melting residue or crystallized from crustal magma Of the minerals, the source of the crust, 87Sr / 86Sr ratio (about 0.709); there is a mineral mantle magma by the crust mixed material products, the 87Sr / 86Sr ratio of medium. Magma is transformed into a SiO2-rich acidic magmatism (plutonic magma) by a sufficient crystallization fractionation in a relatively long-term stable environment (corresponding to the expansion gap in the Okinawa Trough).