MING-QING DYNASTY COSMIC PERIOD
Xu Daoyi;Gao Jianguo;Li Shujing Institute of Geology, State Seismological Bureau Institute of Physics, Academmia Sinica Seismological Publishing House
In China, there are abundant historical records adout earthquakes, severe droughts, river floods, solar activity, meteorites, comets, volcanic eruptions, which indicate long-term variation in the past two thousand years. An obvious correlation between the variations of the phenomena mentioned above is found during 16--17 centuries. This period is characterized by remarkable increase of large earthquakes (M≥8), large quantity of falling meteorites、so called Little Iceage and minimum solar activity. The most striking consistence between the records of large earthquakes and the records of isotope C~(14) peak value of, tree rings, which reflected the result of influencs of cosmic rays on the atmosphere in that period, show just how important cosmic factor is.This consistence between the variations of natural and cosmic phenomena in that period,confirms that there was such a period under the strong influence of cosmic factors, which had a great influence on earthfs dynamic process and solar activity. This period is named the Ming-Qing cosmic period, which ranges from 1500 to 1700 A. D. according to C~(14) data. Analogous association of various natural hazards also occurred in the geological history and at the beginning of the 20th century.Although the cause of the association is not completely clarified yet, it seems that it is impor-tant and interesting to inquire such association to improve on the long-term prediction of great earthquakes and other natural phenomena.