马里亚纳海槽中央轴裂谷中的小扩张脊部位 ,广布火山喷发的玄武岩体 ,海底热液硫化物就是从这些岩体的裂隙中喷溢堆积起来的。利用我国“大洋一号”船拖网所获岩样进行了矿物学和岩石化学特征研究 ,认定为高铝低钾的大洋底玄武岩或拉斑玄武岩系列和钙 -碱玄武岩。为进一步弄清马里亚纳海槽区热液活动岩石学条件和探讨海槽区热液物质来源提供科学证据 The small dilapidated ridges in the central axis rifts of the Mariana Trough, the basalts erupted by the widespread volcanoes, and the seabed hydrothermal sulphides are piled up from the crevices of these rock masses. The mineralogy and petrochemical characteristics of rock samples from the “Dayang No.1” marine trawling network were studied and identified as high-low-kalium basaltic or tholeiite basalts and calcium-base basalts. To provide scientific evidence for further understanding the petrologic conditions of hydrothermal activities in the Mariana Trough area and discussing the source of hydrothermal materials in the trough area