Thermal diffusivity of water under high pressure and high temperature using pulse laser and diamond anvil cell

2014 Fiscal Year Final Research Report

• Project/Area Number: 24740356
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Petrology/Mineralogy/Science of ore deposit
• Research Institution: Ehime University
• Principal Investigator: KIMURA Tomoaki 愛媛大学, 地球深部ダイナミクス研究センター, 特定研究員 (50624540)
• Research Collaborator: KUWAYAMA Yasuhiro 愛媛大学, 地球深部ダイナミクス研究センター, 助教 (00554015) ; OHFUJI Hiroaki 愛媛大学, 地球深部ダイナミクス研究センター, 准教授 (80403864)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: ダイヤモンドアンビルセル / 氷惑星内部構造 / 融解 / 高温高圧実験 / 水 / アンモニア

Outline of Final Research Achievements

A both-sided CO2 laser heating system has been developed for melting and thermal diffusivity measurements of materials contained in the icy planets such as Neptune and Uranus. Melting temperatures of ice, ammonia, and magnesium oxide under high pressure have been determined by using this instrument and a diamond anvil cell. These results suggest that water should remain in the liquid state while ammonia exists as the solid state at the pressure and temperature conditions found deep within the icy planets. These facts imply that not the water predicted by the ab initio calculations but the solid ammonia is one of the dominant constituents of the non-convective layer in the icy mantle, which is responsible for producing the non-dipole magnetic field.

Free Research Field

地球惑星科学