Formation and storage of diamond in Earth's mantle

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We want to understand both the origin and the survival of diamonds in the Earth's mantle. We aim to establish the composition not only of the hot, high-pressure fluids from which the diamonds originally grew but also of any fluids that destroy diamonds deep underground. Inclusions are tiny crystals and fluid droplets that became trapped in the growing diamonds billions of years ago. Thus, they are miniscule time capsules that can reveal the origin and evolution of diamond-bearing rocks in the Earth's mantle. Eons after most diamonds had formed, volcanoes then carried diamonds to the surface together with samples of the deep mantle rock that originally surrounded the diamonds. These samples (known as xenoliths) can provide information on the state of the diamond source rocks at the time of eruption. Combining data from diamond inclusions and xenoliths will allow us to reconstruct the complex evolution of ancient continents and their deep mantle roots through time. Understanding the origin and survival of diamonds is also essential for developing successful strategies to find new sources of diamonds. Over the past two decades, diamond exploration and mining has become the single most important economic force in Canada's remote Arctic regions. At the current pace of mining, new discoveries are urgently needed to sustain the enormous contributions of diamond exploration and mining to the economies of NWT and Nunavut into the next decade. Our research into diamonds and their source rocks will provide crucial new information for selecting target areas and improving geochemical exploration methods.