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The influence of normal fault geometry on igneous sill emplacement and morphology
Craig Magee et al., Dept. of Earth Science and Engineering, Imperial College, London SW7 2BP, UK. Posted online 20 Feb. 2013; http://dx.doi.org/10.1130/G33824.1.
On its route to the surface, magma will often try to take the easiest pathway. This pathway may be pre-existing cracks or faults in the Earth's crust that do not necessarily allow magma to be transported directly upwards. However, our understanding of how magma exploits these fractures is limited. This paper by Craig Magee and colleagues uses 3D seismic reflection data, similar to sonar image through the Earth's crust, to study the shape and distribution of areas where ancient magma (intruded approximately 140 million years ago) has flowed along preexisting faults. They focus on an area offshore the NW coast of Australia called the Exmouth Sub-basin. Their results show that the shape of the faults and the relative magma flow direction control which fractures are exploited. This is important because it means that ascending magma will be localized, potentially controlling the location of volcanic eruptions.
Soil mineral depletion drives early Holocene lake acidification
John Boyle et al., School of Environmental Science, University of Liverpool, Liverpool L69 7ZT, UK. Posted online 20 Feb. 2013; http://dx.doi.org/10.1130/G33907.1.
In recent decades, explanations for post-glacial lake acidification have focused on changing climate and biotic factors. John Boyle and colleagues challenge this
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