Information Extraction Technique Research Of The Crustal Movement's Micro-dynamic Behavior From Continuous GPS Observation At Fiducial Stations

Recently, the employing of GPS observing technique has gained rapid development in the area of studying the global and regional crustal movement and tectonic deformation, and in the exploring of the Geodynamic phenomena. Many GPS continuous observation networks were carried out by various organizations. In China, 25 continuous GPS fiducial sites, 1000 regular observation basic network and irregular observation regional network stations were established in 1998 by the main scientific project named "Crustal Movement Observation Network of China". The data collected by these networks become a foundation for geodynamics.The author has processed and analyzed the observation data obtained from the 25 fiducial stations in CMONC. This paper embodied the selection of regional reference frame for those stations' time series, the calculation of the variations of baseline between two fiducial sites and strain parameters of deformation units, the application of the wavelet analysis and empirical model decomposition to extract the micro-dynamic information of crustal movement, and the issue of the relationship between these behaviors and the stage of major earthquake. Main conclusion and content of this paper is as follows:1) In the analysis of displacement time series, the selection of a suitable regional reference frame is of a possibility to deduct the rigid movement of the research area and the existence of the mainly annual effects of seasonal disturbances. Thus the deducted time series make for easier to extract the micro-dynamic abnormity of the crustal movement.a) As the global reference frame may include holistic rigidity movement (not entirely stable linear movement), we can select a comparatively stable group sites among the 25 fiducial stations as datum of regional reference frame, thus deduct the rigidity movement. Through this way, we got clearer time series include micro-dynamic varieties that may be the reflection of regional deformation.b) Through the reference frame calculations, we found that in such a big research area...