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海水中的He和CH_4异常己被广泛用于确定和表征海洋中经常发生的地方(如洋中脊和海山)中现代热水活动区。本文描述了冲绳海槽中与明显的δ~3He异常相伴的极高的CH_4浓度,给出了陆内弧后盆地中一个受地幔影响的热水系统的第一手资料。 1988年夏季,德国调查船“太阳号”在SO55—56航次中对冲绳海槽中段进行了热水活动和伴生矿化的调查研究。通过测定海水样品中的CH_4和~3He,确定并描述了热水活动地点和类型。冲绳海槽是一个位于琉球沟—弧系统和中国东海大陆架之间的陆内弧后盆地。琉球岛弧由一条非火山外弧(构成主岛链)和一条位于北部的内弧(代表现代火山前沿)构成。冲绳海槽中的弧后扩张可由中央地堑
He and CH_4 anomalies in seawater have been widely used to identify and characterize modern hot water activity areas in places where oceans often occur (such as mid-ocean ridges and seamounts). This paper describes the extremely high concentrations of CH 4 in the Okinawa Trough associated with significant δ ~ 3He anomalies and provides first-hand information on a mantle-affected hot water system in intracontinental back-arc basins. In the summer of 1988, a survey of hot water activities and associated mineralization in the middle Okinawa Trough was conducted by the German survey vessel “Sun” in the SO55-56 voyage. The location and type of hot water activity were identified and described by measuring CH_4 and ~ 3He in seawater samples. The Okinawa Trough is an intracontinental back-arc basin located between the Ryukyu Gutter-Arc System and the East China Sea continental shelf. The Ryukyu Island arc consists of an outer arc that is not volcanic (forming the main island chain) and an inner arc (representing the front of the modern volcano) in the north. Post-arc dilatation in the Okinawa Trough may be dominated by the central graben