Internal Friction of Antarctic Mizuho Ice Cores at Low Frequency

• Main Authors: Nakamura, Tsutomu, Abe, Osamu
• Language: English
• Published: 1978
• Subjects: Antarctic; Mizuho; Mizuho Station; Antarc*; Memoirs of National Institute of Polar Research; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/record/921/files/KJ00000011469.pdf

P(論文) Internal friction and shear modulus of Antarctic ice cores drilled at Mizuho Station were measured with an inverted torsion pendulum in a frequency range of 4 to 9Hz and a temperature range of 96 to 272K. As a function of temperature, the measured internal friction of every core showed two peaks : One around 265K was considered due to the grain boundary and the other around 150K to the mechanical relaxation, because the internal friction of a single crystal has only one peak around 170K corresponding to the latter peak. The height of the former peak decreased with an increase in the density of the core. The shear modulus decreased very slowly with increase of temperature up to around 253K, where internal friction begins to increase sharply. The decrease of shear modulus was more rapid above that temperature. The shear modulus increased linearly with the density. departmental bulletin paper