||自然科学 » 地球科学
||Abstract Recently, Yang et al. (Contrib Mineral Pet- rol 167:1013, 2014a) proposed that “cataclasites,” “brec- cias” and “pseudotachylytes” of eclogites at Yangkou in the Chinese Sulu UHP metamorphic belt are formed by “a compression stress wave of earthquake.” They suggested that the intergranular coesite resulted from a rapid cool- ing from about 700 °C to below 375–400 °C and a “sudden pressure release of seismic wave” from 3.3 to 1.2 GPa in some hours. However, the earthquake-induced UHP meta- morphism under fluid-deficient conditions, proposed by these authors, remains inconclusive and inconsistent with the available data from the UHP metamorphic belt. The coesite inclusions within garnet, zircon and omphacite, and intergranular coesite grains between these minerals can be preserved by the presence of the pressure vessel effect, the lack of fluid infiltration, and the presence of a low-temper- ature and nonhydrostatic deformation environment during rapid exhumation.
Keywords UHP metamorphism · Coesite · Eclogite · Earthquake
本帖最后由 嵇少丞 于 2015-7-1 08:20 编辑 |
|Discussion on “Coesite‐bearing eclogite breccia: implicationfor coseismic ultrahigh‐pressure metamorphism and the rateof the process” by Yang et al. (Contrib. Mineral. Petrol., 2014a,167: 1013)|
Contribution to Mineralogy and Petrology, 2015, 170, 1, 1-6, DOI 10.1007/s00410-015-1154-3