Deep Ocean Tracers and Hydrothermal Vents

克雷格博士在这个项目中的研究一直涉及沿大洋中脊扩展中心的热液喷口的colcolle和同位素化学，这些流体进入深海的通量，以及通过使用这些示踪剂（3He）结合天然放射性同位素研究深海环流。在过去的两年里，他将已知的热液喷口的出现范围扩展到了西南太平洋的弧后盆地（劳、北斐济和马努斯盆地），马里亚纳海槽的西太平洋，以及火山热点，如夏威夷热点上的洛伊吉海山，以及东部微板块上帕斯夸热点上的东太平洋隆起喷口。今年，在两个阿尔文潜水项目中，他在洛伊希火山口取样了30摄氏度的喷口，在我们在马里亚纳海槽发现的两个主要热液区取样了285摄氏度的喷口（“明显的烟囱”）。在1987年底之前，他将在北太平洋和南太平洋的两个太平洋纬向氦喷流上进行一次考察，开始详细绘制太平洋深部环流的这些主要特征。这里报告的新结果包括MOR、Hotspot和弧后喷口中的3He、CH4和Mn关系的细节，喷口流体中的放射性碳和稳定碳同位素。N2O中的ar、N、O同位素等。关于西南太平洋盆地研究（帕帕图亚考察）的一份详细的77页数据报告已经发布。在1987年以后的两年内，没有计划进行新的考察工作。相反，他打算完成1986-87年探险样品和ALVIN计划的所有分析工作，并集中精力进行MOR、热点、弧后和深海同位素和化学研究的解释和合成。

Dr. Craig's research in this program has been concerned with the colatile and isotopic chemistry of hydrothermal vents along the Mid-ocean Ridge spreading centers, the fluxes of these fluids into the deepsea, and the study of the deep circulation by use of these tracers (3He) combines with natural radioactive isotopes. During the past two years he has extended the known occurrences of hydrothermal vents to the Back-arc basins of the SW Pacific (Lau, North Fiji, and Manus Basins), to the western Pacific in the Mariana Trough, and to volcanic hotspots such as Loiji Seamount on the Hawaiian hotspot, and East Pacific Rise vents at the Pascua hotspot on the Eastern microplate. This year in two ALVIN diving programs he has sampled 30'C vents in Loihi caldera, and 285'C vents ("clear smokers") in two major hydrothermal areas we discovered in the Mariana Trough. Before the end of 1987 he will run an expedition transect across the two Pacific zonal helium jets in the North and South Pacific, to begin the detailed mapping of these major features of the deep Pacific circulation, New results reported here include details of the 3He, CH4, and Mn relationships in MOR, Hotspot, and Back-arc vents, radiocarbon and stable carbon isotopes in vent fluids, 39Ar and N and O isotopes in N2O, etc. A detailed 77-page Data Report on the SW Pacific Basin studies (Papatua Expedition) has been issued. No new expedition work is planned after 1987, for the next two years. Rather, he intends to complete all the analytical work on the expedition samples and ALVIN programs of 1986-87, and to concentrate on onterpretation and synthesis of the MOR, hotspot, Back-arc, and deep-ocean isotopic and chemical studies.