Hostname: page-component-848d4c4894-m9kch Total loading time: 0 Render date: 2024-05-11T10:02:36.987Z Has data issue: false hasContentIssue false
  • English
  • Français

Features of the Chandlerian Nutation

Published online by Cambridge University Press:  25 April 2016

H. J. M. Abraham
H. J. M. Abraham*
Affiliation:
Formerly Mount Stromlo and Siding Spring Observatories, Research School of Physical Sciences, The Australian National University, Canberra, Australia
Get access Rights & Permissions [Opens in a new window]

Abstract

Reported data on the Chandlerian nutation show that there are irregular yet related changes in the rate of energy gain, the damping and the phase, changes which were remarkably great in the late 1920s. Dynamical interpretations need a model that has friction elements as well as springs and dashpots; it then offers further applications as well; e.g. to a correlation between reported values of the Love number k and tidal potentials. The model is used in discussing the increases in amplitude and the advances in phase; the short and long-term rates of energy gain and their interruptions and damping; the correlation between short Chandlerian periods and large amplitudes in the annual nutation; and the correlation between damping and the apparent frequency. Doubts are expressed about nutational values of Q. A geophysical interpretation of the model is obtained from seismic data. It was found that every large rise in the nutational energy was preceded by an earthquake in the Andes region; and that the secular rate of energy gain varied with the circum-Pacific seismicity. Decreases in these were accompanied by rises in the Earth’s rotational acceleration and were followed by deep earthquakes in a diminishing region east of the Andes. It appears that the nutational and seismic events are due to tectonic stress, and intermittently this is relieved by subduction.

Type
Contributions
Information
Publications of the Astronomical Society of Australia , Volume 6 , Issue 4 , 1986 , pp. 416 - 424
Copyright
Copyright © Astronomical Society of Australia 1985

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abraham, H. J. M., 1979, Proc. Astron. Soc. Aust., 3, 355.Google Scholar
Bland, D. R., 1960, The theory of linear viscoelasticity, Pergamon Press, Oxford.Google Scholar
Djurovic, D., 1976, Astron. Astrophys., 47, 325.Google Scholar
Djurovic, D. and Melchior, P., 1972, Bull. Classe Sci. Acad. Roy. Belg. 5, LVIII, 248.Google Scholar
Duda, S. J., 1965, Tectonophysics, 2, 409.Google Scholar
Explanatory Supplement to the Astronomical Ephemeris and to the American Ephemeris and Nautical Almanac, 1974, Her Majesty’s Stationery Office, London.Google Scholar
Guinot, B., 1970, Astron. Astrophys., 8, 26.Google Scholar
Guinot, B., 1972, Astron. Astrophys., 19, 207. (I thank Dr Guinot for further data.)Google Scholar
Guinot, B., 1974, Astron. Astrophys., 36, 1.Google Scholar
Jaeger, J. C., 1969, Elasticity, Fracture and Flow, Methuen & Co. Ltd., London.Google Scholar
Melchior, P., 1957, Latitude Variation, Physics and Chemistry of the Earth, 2. Pergamon Press.Google Scholar
Munk, W. H.and MacDonald, G. J. F., 1960, The rotation of the Earth, Cambridge University Press, Cambridge.Google Scholar
Naito, I., 1977, J. Phys. Earth, 25, 221.CrossRefGoogle Scholar
Nicolini, T., 1948, Atti dell Accademia Nazionale dei Lincei, Memorie ser. 7, 2, 1.Google Scholar
Pil’nik, G. P., 1975, Astron. Zhurn. Akad. Nauk SSSR, 52, 178.Google Scholar
Press, F. and Briggs, P., 1975, Nature, 256, 270.Google Scholar
Runcorn, S. K., 1970, ‘Possible cause of the correlation between earthquakes and polar motions, in Earthquake Displacement Fields and the Rotation of the Earth’, (edit, by Mansinka, L., Smylie, D. E.and Beck, A.), pp. 181–187, D. Reidel Publishing Company, Dordrecht.CrossRefGoogle Scholar
Sikiguchi, N., 1972, Pub!. Astron. Soc. Japan, 24, 99.Google Scholar
Stacey, F. D., 1970, ‘A re-examination of core-mantle coupling as the cause of the wobble, in Earthquake Displacement Fields and the Rotation of the Earth’, (edit, by Mansinka, L., Smylie, D. E.and Beck, A.), pp. 176–180, D. Reidel Publishing Company, Dordrecht, Unesco, 1966-1974, Annual summary of information on natural disasters, Paris.Google Scholar
Yumi, S. and Wako, Y., 1966, Pub. Int. Lat. Obs. Mizusawa, 5, 61.Google Scholar