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Author-submitted data information


ID 404
Title Single- and two-station Lg amplitude data obtained from the China National Digital Seismic Network (CNDSN)
Creator Lin Shen
Subject Seismic Lg amplitude data
Publisher Xiukuan Zhao
Description To explore the source parameters including the scalar moment, corner frequency, high-frequency falloff rate, and stress drop, we collected the vertical component waveforms of 95 crustal earthquakes occurred in Changning, Sichuan Province, China during Jun 17 2019 and Sep 30 2019 with magnitudes between 2.8 and 6.0, which were recorded at 597 regional stations and obtained from the China National Digital Seismic Network (CNDSN). We performed source term based on the single- and two-station Lg amplitude data. The Lg-wave signals were sampled using a group velocity window between 3.6 and 3.0 km/s from the vertical component broadband regional waveform data. A time window of the same length was applied before the first P-wave arrival to sample the pre-event noise series. A signal-to-noise ratio (SNR) of 2.0 was used as a criterion for Lg data selection, and the amplitudes of the Lg data set were then obtained after deleting the noise. The two-station Lg amplitude ratios were calculated for the roughly aligned triples of event and station-pair. The resulting single-station amplitudes and two-station amplitude ratios were provided in this Data Repository.
Contributor Lian-Feng Zhao, Xiao-Bi Xie, Xi He, Wei-Min Wang, Zhen-Xing Yao
Date Jun. 17, 2019 to Sep. 30, 2019
Type The Lg amplitudes were sampled at 58 frequencies distributed log-evenly between 0.05 and 10.0 Hz, and therefore the spectral Lg amplitude data were provided in 58 separated files, with each file corresponding to one frequency indicated by the double-digit number in the name of the file.
Format All Lg amplitude data, including single-station amplitudes and two-station amplitude ratios, were stored in the ASCII Sott.*.b.dat files. The correspondence between the frequency and the double-digit number can be looked up in the file ‘parameters.txt’. The Sott.*.b.dat files consist of header lines and data lines. Natural number and zero value occupy the 4th and 5th columns, respectively, which indicates that the current line is the header line for single-station data, where natural number is the sequence number of the recorded event, with the first two columns being the longitude and latitude of the recorded event, 3rd column being the number of lines of the following station data. The header lines for single-station data are immediately followed by data lines, with the columns successively being the longitude and latitude of the recording station, Lg amplitude, geometric spreading term, sequence number of the recording station, and earthquake magnitude. In contrast, zero and natural number occupy the 4th and 5th columns, respectively, which indicates that the current line is the header line for two-station data, where natural number is the sequence number of the recording station, with the first two columns being the longitude and latitude of the station location, 3rd column being the number of lines of the following two-station data. The header lines for two-station data are immediately followed by data lines of two-station data, with the columns successively being the longitude and latitude of the in-between station, inter-station ratio of Lg amplitude, geometric spreading term, sequence number of the in-between station, and earthquake magnitude.
URL http://www.geophys.ac.cn/ArticleData/20220311LgObservations.zip
DOI 10.12197/2022GA005
Source
Language eng
Relation
Coverage
Rights Institute of Geology and Geophysics, Chinese Academy of Sciences; China National Digital Seismic Network