Collaborative Research on the Iceland Deep Drilling Project: An Investigation of a High-Temperature Mid-Ocean Ridge Hydrothermal System in a 5 km Deep Borehole

0507625老年人冰岛深钻项目（IDDP）将研究高温（~ 450 ℃）热液与冰岛西南端雷克雅内斯半岛洋壳的相互作用，大西洋中脊在那里露出海洋。 所要求的资金将是高度杠杆化的，因为钻一个5公里深的钻孔的大部分成本将由工业和冰岛政府承担，并由国际大陆科学钻探计划参与。 冰岛一家地热发电公司正在提供一口现有的约3公里深的井，以便将其加深到5公里深。该项目将在全世界首次提供机会，调查大洋中脊热液系统的深层高温反应区，这是大洋钻探方案的一个长期目标。 这个钻探地点非常适合进行广泛的科学研究，涉及玄武岩和海水在高温下的反应，达到超临界条件。 在控制黑烟流体成分的深层高温反应区中的这种活跃过程以前从未可用于全面的直接研究和取样。大洋钻探仅深入到5 Ma的洋壳2公里。温度约为180摄氏度。 相比之下，IDDP与冰岛工业界的合作将从3、4和5公里处的流动测试中产生流体样品，钻屑和现场岩心深至4.0公里，以及从4.0至5.0公里深的1.0公里连续岩心。这些样品将揭示400 ℃时玄武岩-海水相互作用的综合记录。对这些材料的研究将使我们对全球范围内重要的活跃热液过程的理解有一个巨大的飞跃，所提供的资金将用于：（1）为科学目的取芯;（2）支持井场的科学计划、流体取样、岩心处理和岩心的基本岩石学表征，并将子样本和数据分发给经批准的国际科学家名单;以及（3）支持一个由美国共同参与者组成的协调小组，调查热液水/岩石相互作用和地球化学建模。 将被取回的岩心和流体可能是一个主要热液系统的下边界的特征，从而提供关于控制热液系统温度上限的因素的重要证据。

0507625EldersThe Iceland Deep Drilling Project (IDDP) will study the interaction of high-temperature (~ 450oC) hydrothermal fluids with oceanic crust on the Reykjanes Peninsula, at the southwestern tip of Iceland, where the Mid-Atlantic Ridge emerges from the ocean. The requested funds would be highly leveraged because most of the cost of drilling a 5km deep borehole will be borne by industry and the Icelandic government, with participation from the International Continental Scientific Drilling Program. An Icelandic geothermal power company is providing an existing ~ 3 km deep well for deepening to 5 km depth. This project will provide the first opportunity worldwide to investigate the deep, high temperature reaction zone of a mid-ocean ridge hydrothermal system, which has been a long-standing goal of the Ocean Drilling Program. This drill site is ideally situated for a broad array of scientific studies involving reactions between basalt and seawater at high temperatures, reaching supercritical conditions. Such active processes in the deep, high temperature reaction zones that control fluid compositions of black smokers have never before been available for comprehensive direct study and sampling. Ocean drilling has penetrated only 2 km into 5 Ma old ocean crust. where temperatures were ~ 180 oC. In contrast, the IDDP collaboration with industry in Iceland will produce fluid samples from the flow tests at 3, 4, and 5 km, drill cuttings and spot cores down to 4.0 km depth, and 1.0 km of continuous drill core from 4.0 to 5.0 km depth. These samples will reveal the integrated record of basalt-seawater interactions at 400oC. The study of these materials will permit a quantum leap in our understanding of active hydrothermal processes that are important on a global scale, The funds provided will be used for: (1) coring for scientific purposes; (2) support for the scientific program at the well site, for fluid sampling, for core handling, and for basic petrologic characterization of the cores, and distribution of sub-samples and data to an approved list of international scientists; and (3) support for a coordinated group of US Co-PI's investigating hydrothermal water/rock interactions and geochemical modeling. The core and fluids that will be retrieved may characterize the lower boundary of a major hydrothermal system and thus provide important evidence about what controls the upper temperature limits of hydrothermal systems.