Geochemical Applications of Noble Gases

Noble gases are unique tracers, due to their rarity on Earth and their inertness. Several of their isotopes are produced by nuclear reactions, whereas others were trapped when the Earth formed. They have been widely used for understanding the evolution and structure of the Earth, dating geological events/processes, characterizing magma genesis and volcanism in different tectonic environments, tracing mantle-crust interaction even in non-volcanic areas, and for monitoring earthquake and volcanic activities. Some of these topics were presented at the 9th International Conferences on Gas Geochemistry that was held in 2007 in Taipei, Taiwan. This special volume includes twelve papers, which cover a wide range of applications of noble gases geochemistry such as tracing the thermal evolution of the early Earth, understanding the mantle source of continental basalts, establishing the spatial variations of gas compositions in hot springs and fumaroles from volcanic and forearc areas, as well as in key non-volcanic areas such as faults and seismic zones, and tracing the origin and evolution of ore-forming fluids of uranium deposits; reproducing the noble gas behavior during faulting, and, finally, using argon as a tracer of large-scale geologic processes.