Detail Elastic Anisotropy of Earth's Inner Core   Oleh:  Belonoshko, Anatoly B. ; Skorodumova, Natalia V. ; Rosengren, Anders ; Johansson, Börje Jenis: Article from Bulletin/Magazine Dalam koleksi: SCIENCE (keterangan: ada di Proquest) vol. 319 no. 5864 (Feb. 2008), page 797-799. Topik: Elastic Anisotropy; Earth's Inner Core Ketersediaan Perpustakaan FK Nomor Panggil: S01.K.2008.02 Non-tandon: 1 (dapat dipinjam: 0) Tandon: tidak ada     Lihat Detail Induk Isi artikel Earth's solid-iron inner core is elastically anisotropic. Sound waves propagate faster along Earth's spin axis than in the equatorial plane. This anisotropy has previously been explained by a preferred orientation of the iron alloy hexagonal crystals. However, hexagonal iron becomes increasingly isotropic on increasing temperature at pressures of the inner core and is therefore unlikely to cause the anisotropy. An alternative explanation, supported by diamond anvil cell experiments, is that iron adopts a body-centered cubic form in the inner core. We show, by molecular dynamics simulations, that the body-centered cubic iron phase is extremely anisotropic to sound waves despite its high symmetry. Direct simulations of seismic wave propagation reveal an anisotropy of 12%, a value adequate to explain the anisotropy of the inner core. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Kembali

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