[S-IT17] TRANSPORT PROPERTIES AND PROCESSES IN THE EARTH

[SIT17-08] Effects of hydrous minerals’ thermal conductivity on Earth’s evolution dynamics

★Invited Papers

*Wen-Pin Hsieh¹ (1.Academia Sinica, Taiwan)

Keywords:thermal conductivity, hydrous minerals, geodynamics

Through slab subduction, hydrous minerals can be brought into the Earth’s deep interior, impacting its physical, chemical, rheological, and geodynamical properties. An important question is whether the hydrous minerals could cause thermal and geodynamical anomalies in Earth interior. To answer this, knowledge to the thermal conductivity of hydrous minerals under relevant pressure and temperature conditions is critically required. Recently we have studied the thermal conductivity of a series of hydrous phases under high pressure-temperature conditions. We found that the presence of water, acting as defects, in the mantle minerals can substantially reduce their thermal conductivity. Combined with numerical simulations, we further showed that the thermal conductivity anomaly could in turn induce a number of anomalies in local thermal state, stability zone of minerals, seismic structure, and subduction dynamics of a slab. Recent ongoing and future experiments on the melts will also be discussed in the talk.