Geothermal systems related to rapid uplift on the Alpine Fault, New Zealand

与新西兰高山断层快速隆升相关的地热系统

• 批准号: NE/H012842/1
• 负责人: Damon Teagle
• 金额: $ 6.87万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FH012842%2F1
• 关键词: Geothermal; systems; related; rapid; uplift

Although the largest earthquakes (e.g., 2004 Sumatra) occur where tectonic plates collide, large earthquakes (Mag. 7-8+) also occur on strike-slip faults where plates are moving horizontally past each other. Strike-slip faults such as the San Andreas or the North Anatolian Fault (Turkey) occur in highly populated areas where earthquakes can have devastating human consequences. Although faults are seismic monitored, our knowledge of why earthquakes occur remains poor. This is because we have no samples of rocks that ruptured during a modern earthquake because failure typically occurs deep in the crust (>5-10 km). Nor do we have in situ measurements of the thermal and fluids conditions that determine how materials respond to the relative motion of the plates. Ancient fault rocks do occur but these rocks are commonly altered and have unknown tectonic context. The Alpine Fault is major strike-slip fault, that runs along the western range front of the Southern Alps, New Zealand. The fault is the boundary between the Australian and Pacific plates with the Australian crust moving to the northeast at ~27 mm/year. Because plate motions are not parallel to the Alpine Fault, collision is occurring at an oblique angle. This has resulted in the recent (~5 million years) rapid (>6-8 mm/yr) uplift of the Pacific plate over the Australian plate forming the >3000 m-high Southern Alps. Rocks, that until a few million years ago where more than 25 km deep in the crust, now crop out at the surface along the fault. Importantly, rocks that as recently as a few 10s of thousands of years ago, were fracturing and deforming within the Alpine Fault zone itself, now occur at the surface. This well known tectonic geometry and one-sided uplift along a major strike-slip fault is unique, and provides an excellent natural laboratory to understand earthquake processes. It is surprising that there have been no large earthquakes on the Alpine Fault in European times. However, paleo-seismic evidence indicates a major earthquake in ~1717, and that large earthquakes occurr every 200-400 years. These quakes were very large with up to 8 m horizontal movement in each event. The Alpine Fault is late in its seismic cycle and overdue for a large, devastating earthquake. This has lead an international group of scientists to propose drilling a series of shallow and deep (~4 km) bore holes into the Alpine Fault Zone to sample the fault rocks in situ, and to install instruments (seismicity, strain, temperature, fluid pressure) to monitor a major fault during the final build up to a large earthquake. Data from the Alpine fault can be used to understand other fault zones. Before we can decide where to drill a deep hole, we need to know how hot it is at the target depth. Our proposed work will make estimates of the temperature of rocks at depth by investigating geothermal warm springs (up to 60 deg C) that occur along the Alpine Fault. These warm springs occur because rapid uplift has brought deep hot rocks near to the surface. Geologists commonly use fluids from geysers or seafloor black-smoker vents, as windows into conditions deep within the crust. The chemistry of fluids and gases emitted can tell us where the fluids come from and how they have reacted. Unfortunately, there is very little known about the Alpine Fault geothermal systems because many of the springs are in very remote locations, and the scientists didn't have access to modern techniques. From investigating fluid-rock exchange in other hydrothermal environments, we have developed new methods to understand reactions between fluids and minerals. We will match warm spring fluids to minerals that formed within the Alpine Fault zone, during different stages of the uplift of these rocks to the surface. When matches can be made, we will be know that the reactions and conditions producing modern fluids must be occurring within the Alpine Fault today.

尽管最大的地震（例如，2004年苏门答腊）发生在构造板碰撞的情况下，但大地震（Mag。7-8+）也发生在板板彼此水平移动的走滑断层上。在人口稠密的地区，地震可能造成毁灭性的人类后果，诸如圣安德烈亚斯（San Andreas）或北安纳托利亚断层（Turkey）之类的走滑断层发生。尽管对断层进行了监测，但我们对为什么地震发生的知识仍然很差。这是因为我们没有在现代地震期间破裂的岩石样本，因为故障通常发生在地壳中（> 5-10 km）。我们也没有对热和流体条件的原位测量，这些条件决定了材料对板的相对运动的反应。确实发生了古老的断层岩石，但是这些岩石通常会改变，并且具有未知的构造背景。高山断层是主要的滑移断层，沿新西兰南部阿尔卑斯山的西部范围延伸。故障是澳大利亚和太平洋板块之间的边界，澳大利亚地壳以约27毫米/年移动到东北。因为板运动与高山断层不平行，所以碰撞以倾斜角度发生。这导致了最近（约500万年）的快速（> 6-8 mm/yr）的太平洋板块，超过了澳大利亚板块，形成了> 3000 m高的南方阿尔卑斯山。岩石，直到几百万年前，地壳深25公里，现在沿着断层散发出碎片。重要的是，现在几千年前几千年前的岩石在高山断层区本身内部破裂和变形，现在出现在表面。这种众所周知的构造几何形状和沿主要滑移断层的单侧隆起是独一无二的，它为了解地震过程提供了出色的自然实验室。令人惊讶的是，欧洲时代的高山断层没有大地震。然而，古理性证据表明1717年发生了重大地震，每200 - 400年就发生大地震。这些地震在每个事件中都非常大，最多8 m的水平运动。高山断层在其地震周期后期为较晚，并且对于大型毁灭性地震而逾期。这导致一组国际科学家提议钻探一系列浅和深（4公里）的孔孔到高山断层区，以在原位进行故障岩石进行采样，并安装仪器（地震性，应变，温度，温度，流体压力），以监测最终积聚到大型地震期间的主要断层。来自高山故障的数据可用于了解其他故障区域。在我们决定在哪里钻一个深孔之前，我们需要知道目标深度在目标深度处的热度。我们提出的工作将通过研究沿高山断层发生的地热温泉（高达60°C）来估计深度的岩石温度。这些温暖的弹簧之所以发生，是因为快速升高使深层热岩石靠近地面。地质学家通常使用地间歇泉或海底黑人烟雾的液体作为窗户进入地壳深处的条件。排放的流体和气体的化学性能告诉我们流体的来源以及它们的反应方式。不幸的是，关于高山故障地热系统鲜为人知，因为许多弹簧都在非常偏远的位置，科学家无法使用现代技术。从研究其他水热环境中的流体岩石交换，我们开发了新的方法来了解流体和矿物质之间的反应。我们将在这些岩石向表面的不同阶段的不同阶段，将温暖的弹簧液与在高山断层区域内形成的矿物匹配。当可以进行比赛时，我们将知道，当今高山断层内必须发生产生现代液体的反应和条件。

项目成果

Carbon dioxide generation and drawdown during active orogenesis of siliciclastic rocks in the Southern Alps, New Zealand

新西兰南阿尔卑斯山硅质碎屑岩活跃造山作用期间二氧化碳的产生和减少

• DOI: 10.1016/j.epsl.2017.10.010
• 发表时间: 2018
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Menzies C

Mobility of Au and related elements during the hydrothermal alteration of the oceanic crust: implications for the sources of metals in VMS deposits

• DOI: 10.1007/s00126-015-0598-8
• 发表时间: 2016-02
• 期刊: Mineralium Deposita
• 影响因子: 4.8
• 作者: C. Patten;I. Pitcairn;D. Teagle;M. Harris

The fluid budget of a continental plate boundary fault: Quantification from the Alpine Fault, New Zealand

• DOI: 10.1016/j.epsl.2016.03.046
• 发表时间: 2016-07
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: C. Menzies;D. Teagle;S. Niedermann;S. Cox;D. Craw;M. Zimmer;M. Cooper;J. Erzinger

Carbonate alteration of ophiolitic rocks in the Arabian-Nubian Shield of Egypt: sources and compositions of the carbonating fluid and implications for the formation of Au deposits

• DOI: 10.1080/00206814.2016.1227281
• 发表时间: 2017-03-01
• 期刊: INTERNATIONAL GEOLOGY REVIEW
• 影响因子: 2.6
• 作者: Boskabadi, Arman;Pitcairn, Iain K.;Majka, Jaroslaw
• 通讯作者: Majka, Jaroslaw

Incursion of meteoric waters into the ductile regime in an active orogen

• DOI: 10.1016/j.epsl.2014.04.046
• 发表时间: 2014-08-01
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Menzies, Catriona D.;Teagle, Damon A. H.;Roberts, Stephen
• 通讯作者: Roberts, Stephen