GEOLOGY AND SLOW GROUND MOTION ON FUTURE

The power spectrum density and coherence function for slow ground motions are studied for the construction of the large future electron-positron linear collider. Dominant part of the ground motion in the low frequency range (f<0.1 Hz) is usually related to the ATL model using the integrated power spectrum density. Recently we have obtained new information on the ground motion. The coherency of the ground motion changes as a function of detailed geological condition even though the value of A is not so different between each other. We will present detailed discussion about this new information. 1 GROUND MOTION AND ATL Many measurements on the ground motion were made for several accelerator sites and their related sites, sinc