الفهرس 
PrefaceOnly 14 pages are availabe for public view
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Abstract
The evaluation of the quality of observed seismic records is important to substantiate and confirm the integrity of the seismic data sets. Therefore, the current thesis is presented to deal with seismic data quality control for the Egyptian National Seismic Network (ENSN) which will support the engineering, safety assessment and scientific community with highly qualified data and information. For this purpose, data set recorded by (32) broad band stations were collected, preprocessed, and used to well define and characterize Ambient Earth Vibration (AEV), ware identified different types of noise such )Cultural noise, Wind, water and geological noise, Microseisms and System artifact in the PDF noise field like data gaps and sensor glitches. This is useful for quality management of the seismic network. Furthermore, the seismic activity was diurnally seasonally influenced. In order to better assessment, the seismic stations of the Egyptian national seismic network are spatially divided into four subnets of the broad band stations in a) Zone-1 (Cairo broad band stations), Zone-2 (Northern Coast), Zone-3 (Red Sea) and Zone-4 and (Aswan) region. The results of the present analyses each zone are presented in terms of the annual variation, the transfer functions and probability density function PDF for each station within the subnet. In general, the broadband seismic stations of Egyptian National Seismic Network provide good quality data .however, their sites must be upgraded to minimize the culture noise The output function due to reveal that, in some frequency ranges, some stations have very poor detectability and higher noise levels that impair the monitoring of seismic events. Although the other stations demonstrate outstanding results. A noise map is created demonstrating the noise characteristics of the Aswan sub-network of the ENSN for different times scales. The effect of high-dam turbines on seismic data at frequency of 2 Hz was also observed. The output of this analyses will be helpful in detecting the operational problems for Egyptian National Seismic Network stations will be important to the potential positioning of the ENSN stations will support the upgrading issue of ENSN. The main result is that the noise assessment test must be carried out prior to the final selection of seismic station at the construction sites. In addition, it is advised to apply the PQLX technique to ENSN as a standard method, which would be useful for seismic station status tests.