LONG-TERM EVOLUTION OF THE SOLAR INSOLATION VARIATION OVER 4GA

Solar insolation variation due to the gravitational perturbation among the planetary bodies in the solar system, so called the Milankovitch cycle, is widely believed as a major cause of the climatic change such as the glacial-intel glacial cycles in Quaternary, and its typical fr equencies are supposed to be constant during Quaternary. However, the periods of these cycles must have been largely changed following to th e dynamical evolution of the earth-moon system. We have studied the re lation between the frequencies of the Milankovitch cycles and the rota tion rate of the earth on the basis of theoretical and computational a nalysis of the earth-moon system. Our conclusion is that this cyclicit y which can be recorded in the sediments are mutually related well as a function of the dynamical ellipticity and the absolute age. This fac t implies that we can establish the standard time scale for measuring the relative age, in other words, the lap time clock or the chronomete r for decoding the whole history of the earth, by comparing the stripe s in BIF and other sediments of Archean or Proterozoic with a set of t heoretical Milankovitch cycle and tidal cycle frequencies.