Determining gypsum growth temperatures using monophase fluid inclusionsApplication to the giant gypsum crystals of Naica, Mexico
Yves Krger et al., Institute of Applied Physics, University of Bern, Bern, Switzerland; corresponding author: Juan Manuel Garca-Ruiz, Laboratorio de Estudios Cristalogrficos, IACT, CSIC, Universidad de Granada, Granada, Spain. Posted online 28 Nov. 2012; http://dx.doi.org/10.1130/G33581.1.
Determining the formation temperature of minerals using fluid inclusions is a crucial step in understanding rock-forming scenarios. Unfortunately, fluid inclusions in minerals formed at low temperature, such as gypsum, are commonly in a metastable monophase liquid state. To overcome this problem, ultra-short laser pulses can be used to induce vapor bubble nucleation, thus creating a stable two-phase fluid inclusion appropriate for subsequent measurements of the liquid-vapor homogenization temperature, Th. In this study, Kruger and colleagues evaluate the applicability of Th data to accurately determine gypsum formation temperatures. Their results support the earlier hypothesis that the population and the size of the Naica crystals were controlled by temperature. In addition, this experimental method opens a door to determining the growth temperature of minerals forming in low-temperature environments.
Provenance of North Atlantic ice-rafted debris during the last deglaciationA new application of U-Pb rutile and zircon geochronology
David Small et al., School of Geography and Geosciences, University of St Andrews, North Street, St Andrews, Fife KY16 9AL, Scotland, UK. Posted online 28 Nov. 2012; http://dx.doi.org/10.1130/G33594.1.
North Atlantic Ocean sedim
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