ESA is due to launch the three-satellite mission, SWARM, in 2010 as part of its Earth Explorer programme, which is strategic for the geomagnetic element of Earth Observation. The planned multi-spacecraft formation (in low earth, polar orbit), and payload of magnetic and electric field instruments, are specifically designed to study all contributions to the near-Earth magnetic field, including the internally generated and surface (Lithospheric) geomagnetic field, and the externally influenced ionospheric and magnetospheric fields; together with their associated electric current systems. The key difference in the mission design of SWARM over previous low orbit missions (e.g. Champ and Öersted), is its multi-spacecraft nature, which allows gradient and partial current estimates to be made directly, in-situ. These measurements are critical to capture and distinguish the time-variability of the geomagnetic field, which otherwise inherently limits the accuracy of field models developed from single spacecraft missions (despite the high precision measurements now available). A key mission aim of SWARM is therefore to map the ionospheric current system, linking into the magnetosphere, and monitor behaviour directly to better understand the responses of the Earth's environment. The essentially anisotropic conductivity, and field aligned linkage of currents, requires multi-point measurements of both the magnetic and electric field, and these observations also provide continuous monitoring of the impact of space weather; potentially completing a full solar cycle of previous magnetic measurements. The exploration intended by the SWARM mission, both to survey the geomagnetic field and to distinguish the various dynamic sources contributing to the mechanisms of energy transfer in the Earth's environment, is therefore of high interest, and has close relevance to NCEO aims. ESA plans to present no-cost AOs for guest investigators to validate SWARM data products, who will thereby gain access to the SWARM data set a year before public release. It is therefore desirable to position the UK community to respond to these AOs, which assume national funding will be sought. NCEO funding for this mission support activity, as applied for here, would achieve this. The calibration and analysis techniques will be developed from knowledge gained through the operation of the four-spacecraft Cluster (and other) spacecraft (which can provide determination of electric current density, for example), while verification of the electric field will exploit existing methods, using ionospheric data from the EISCAT radar and SuperDARN network (which can provide reference electric field values through the measured global convection flows). Cluster has provided vital lessons for access, validation and use of SWARM data; multi-point techniques will maximise the science return, while the radar network provides a global interpretation for the in situ observations. On this basis, extensive studies can be performed to qualify and exploit the SWARM dataset through and beyond the mission operations.

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.