Magnetotelluric instrumentation for geophysics and space physics

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This proposal requests support to purchase two magnetotelluric instruments for use in research and teaching in geophysics and space physics. These instruments measure naturally occurring electromagnetic (radio) waves that are generated in space and travel into the Earth.******In the geophysical studies the instruments will measure the signals at the surface of the Earth. From measurements at a grid of points, a 3-D image of the Earth can be derived, just as X-rays are used to look inside the human body. These measurements provide information about the electrical resistivity of the Earth, a property that is sensitive to the presence of water, molten rock and certain economically important minerals. The instruments will be used in geophysical research at the University of Alberta that includes :******(1) Studies of plate tectonics which are important for reducing the risks posed by major earthquakes in Canada and South America.******(2) Exploration for geothermal energy to find hot water that can be used for heating and electricity generation. This is an important for Canada's transition from fossil fuels to renewable energy.******(3) Investigations of active volcanoes in Canada and South America where they are used to locate molten rock to understand the risks of eruption.******(4) In developing exploration tools to search for the minerals needed for the Canadian economy.******In space physics the instruments will measure the radio waves at the surface of the Earth. The research will address how these waves can interfere with power grids in two ways.******(1) To understand how these signals are generated, and what conditions lead to strong, potentially damaging signals. The ground based measurements will complement satellite measurements by better defining the location of signal generation. ******(2) When these waves reach the Earth, they generate electric currents in both the ground and power grids. The amount of current depends on the Earth's magnetic field, the structure of the Earth and the layout of the power grid. Predictions of the strength of electric current is needed to reduce damage to power grids during magnetic storms. Computer models can predict the impact on the grid, but are limited by a lack of suitable observations. Measurements made with these instruments will improve the accuracy of predictions and thereby reduce the resulting damage to power grids caused by space weather. This research is economically important to Canadian power companies and anyone who relies on electric power supply. Power regulators in Canada are developing requirements for these risks to be addressed.******As well as making important research possible, the instruments will be used to train undergraduate and graduate students at the University of Alberta and Athabasca University. These students will be qualified to work in careers in (a) geophysics, both reducing hazards and exploring for resources and (b) in space physics to reduce hazards from space weather and other applications.