第145回ジオダイナミクスセミナー
Geodynamics Seminar
"Physical Constraints on the Ultra-low Velocity Zone
at the Lowermost Mantle"
講師：出原 光暉（愛媛大学博士1年）
主催 ： 愛媛大学地球深部ダイナミクス研究センター
日時 ： ２００６年２月３日（金）17：00〜
場所 ： 愛媛大学理学部講義棟 ３０１教室
要 旨
In this seminar, we characterize the physical properties of the Ultra-low velocity zones (ULVZs) by using a large amount of core- reflected PcP and ScP phases data which densely samples the CMB region beneath western Pacific. Clear postcursors to ScP are detected from several contiguous events whose rays sampled beneath Philippine- Kalimantan and East of Australia, indicatingthe existence of the ULVZ in the regions.? All of our data with clear ScP postcursors are best explained with the anomaly ratio of shear-to-compressional velocity of ~2.5 and that of density-to-shear velocity of ~-0.33, and all are fitted with shear velocity change of up to -40%. The pattern of those anomaly ratios is quite consistent with the pattern which is expected by the change of the Fe content in perovskite and ferropericlace.
問い合わせ先：土屋 卓久 TEL （089）927-8198
E-mail takut@sci.ehime-u.ac.jp
