Natural supersaturation conditions needed for nucleation of air-clathrate hydrates in deep ice sheets

• Uchida, Tsutomu

• Yasuda, Keita

• Ot, Yuya

• Shen, Renkai

• Ohmura, Ryo

抄録

We apply new phase-equilibrium data of air-clathrate hydrates to the distribution of air hydrates in deep ice sheets to better understand their nucleation conditions. By comparing the depths at which the hydrates first appear to the phase-equilibrium condition, we estimated the critical size of an air-hydrate nucleus in an ice sheet to be similar to 50 nm. The estimated energy barrier for nucleation, based on the temperature dependence of supersaturation, is much smaller than that estimated previously for the pure ice system. Thus, the bubble surface may either act as a type of heterogeneous nucleus, or contain heterogeneous nuclei, for hydrate formation. Competition between nucleation-promotion and nucleation-inhibition factors may increase variation in nucleation rates, resulting in variation of the depth range of the bubble hydrate transition zones.

収録刊行物

• Journal of glaciology

  Journal of glaciology 60 (224), 1111-1116, 2015-02-04

  International Glaciological Society

キーワード

• clathrate hydrates
• crystal growth
• ice core

詳細情報

• CRID: 1050845763948162176
• NII論文ID: 120005625289
• HANDLE: 2115/59590
• ISSN: 00221430
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles