TY - JOUR
T1 - Chemical reaction diversity of geofluids revealed by hydrothermal experiments under sub- and supercritical states
AU - Tsuchiya, Noriyoshi
AU - Hirano, Nobuo
PY - 2007/3/1
Y1 - 2007/3/1
N2 - Hydrothermal experiments of dissolution of granite and quartz with pure water up to 600°C and 60MPa were carried out in order to evaluate chemical reaction under sub- and supercritical conditions. The supercritical region beyond the critical point for water has been inferred to be a homogeneous state, which does not correspond to either a true liquid phase, or a true vapor phase. Results of dissolution experiments of granite and quartz in a supercritical state (artificially defined as higher pressures and temperatures than the critical point), show this fluid can be subdivided into two apparent phases comprising a 'liquid-like' region and a 'vapor-like' region. Chemical phenomena with respect to dissolution reactions in the 'liquid-like' region are more similar to those of subcritical water, whilst those reactions in the 'vapor-like' region even in the supercritical state are considered to be weak. The critical point of various kinds of geofluids, composed of solutions in the H2O-CO2-NaCl system was experimentally determined using a visible type autoclave. Chemical reaction diversity, depending on location of the critical point for a given solution and apparent phase boundary in terms of chemical reaction within the supercritical state, was recognized by hydrothermal experiments.
AB - Hydrothermal experiments of dissolution of granite and quartz with pure water up to 600°C and 60MPa were carried out in order to evaluate chemical reaction under sub- and supercritical conditions. The supercritical region beyond the critical point for water has been inferred to be a homogeneous state, which does not correspond to either a true liquid phase, or a true vapor phase. Results of dissolution experiments of granite and quartz in a supercritical state (artificially defined as higher pressures and temperatures than the critical point), show this fluid can be subdivided into two apparent phases comprising a 'liquid-like' region and a 'vapor-like' region. Chemical phenomena with respect to dissolution reactions in the 'liquid-like' region are more similar to those of subcritical water, whilst those reactions in the 'vapor-like' region even in the supercritical state are considered to be weak. The critical point of various kinds of geofluids, composed of solutions in the H2O-CO2-NaCl system was experimentally determined using a visible type autoclave. Chemical reaction diversity, depending on location of the critical point for a given solution and apparent phase boundary in terms of chemical reaction within the supercritical state, was recognized by hydrothermal experiments.
KW - Chemical reaction
KW - Critical point
KW - Dissolution
KW - Geofluid
KW - Hydrothermal experiment
KW - Supercritical state
KW - Water-rock interaction
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U2 - 10.1111/j.1440-1738.2007.00554.x
DO - 10.1111/j.1440-1738.2007.00554.x
M3 - Article
AN - SCOPUS:33847071631
VL - 16
SP - 6
EP - 15
JO - Island Arc
JF - Island Arc
SN - 1038-4871
IS - 1
ER -