The Pan-Third Polar region has strong seismic activity, which is driven by the subduction and collision of the Indian plate, the Arab plate and the Eurasian plate. 18806 earthquakes with Magnitude 5 or larger have occurred in Pan-Third Polar region (north latitude 0-56 degrees and east longitude 43-139 degrees) since 1960. Among them, 4 earthquakes with Magnitude 8 or larger, 187 earthquakes with Magnitude 7.0-7.9, 1625 earthquakes with Magnitude 6.0-6.9 and 16990 earthquakes with Magnitude 5.0-5.9 have occurred. Earthquakes occurred mainly in the foothills of the India-Myanmar Mountains, the Himalaya Mountains, the Sulaiman Mountains, where the India Plate collided with the Eurasian plate, and the Zagros Mountains where the Arab plate collided with the Eurasian plate.
WANG Ji
We compiled the Seismic Zonation Map of Western Asia using the ArcGIS platform through data collecting and digitization. The Seismic Zonation map of Western Asia covers Iran and its surrounding countries and regions. Based on the “Major active faults of Iran” map, the map is replenished with massive published data and depicts the location and nature of the seisogenic faults or active faults and the epicenter of earthquakes with M ≥ 5 from 1960 to 2019. The zonation map shows the mean values of peak ground acceleration (PGA) with 10% probability of being exceeded in 50 years. The two maps can not only be used in the research of active faults and seismic risks in Western Asia, but also will be applied to the seismic safety evaluation for infrastructure construction.
LIU Zhicheng
This data comes from the result of teleseismic data, mainly including the velocity and radial anisotropic structures beneath western Tibet. In the process of processing, bandwidth filtering is adopted, and the filtering range is 0.05-2 Hz. Due to the use of teleseismic data, the cross-correlation method is used in the acquisition process to "align" the waveform. The data quality is good, because the extracted data are all from the earthquakes with magnitude greater than 5.0 located in the global seismic catalog, and each event has an obvious take-off point. The data can be used by other seismologists to reconstruct and analyze the underground structures in this area.
ZHANG Heng
The 2015 Gorkha, Nepal earthquake (Mw 7.8) ruptured the Main Himalayan Thrust (MHT) and allows direct measurements of the behavior of the continental collision zone. We study the MHT using seismic waveforms recorded by local stations that completely cover the aftershock zone (Event catalog 1.docx and Event catalog 2.docx). We obtained the velocity structure beneath the study zone (Velocity.dat). The MHT exhibits clear lateral variation along geologic strike, with the Lesser Himalayan ramp having moderate dip on the MHT beneath the mainshock area and a flatter and deeper MHT beneath the eastern end of the aftershock zone. East of the aftershock zone, seismic wave speed increases at MHT depths, perhaps due to subduction of an Indian basement ridge. A similar magnitude wave speed change occurs at the western end of the aftershock zone. These gross morphological structures of the MHT controlled the rupture length of the Gorkha earthquake.
We use waveform cross-correlation to analyze the recordings of eight earthquakes (2009-2018) beneath the Indian Ocean at stations from the Chinese Digital Seismic Network. We obtain 929 high quality residual traveltime differences between the phases ScS and S (Differential traveltimes.dat). We interpret variations of δt up to 10 seconds as due to horizontal shear-velocity variations in D” beneath northern India, Nepal, and southwestern China. The shear velocity can vary by as much as 7% over distances shorter than 300 km. Our observations provide additional observational evidence that compositional heterogeneity and possibly melt contribute to the seismic structure of the lower mantle characterized by long-term subduction and mantle downwelling.
LI Guohui, BAI Ling
This data set is used to analyze the global activity level of strong earthquakes (Mw 5) in the past 30 years, and to present it spatially. It can be used to obtain the distribution areas of strong earthquakes with high frequency and activity level in recent years. By comparing the distribution of strong earthquakes in 2018 with that in 1989-2018, the distribution characteristics of global strong earthquakes in 2018 are obtained. The original data of strong earthquakes are from USGS, and the local density is calculated as frequency information. The magnitudes of all earthquake cases are interpolated globally, and then the frequency and magnitude are multiplied as the activity level of strong earthquakes. The data set is in TIff format with a spatial resolution of about 80 km. The data set can provide a reference for the analysis of strong earthquake activity level on the global scale, and is helpful for the analysis of global earthquake risk and the construction of earthquake prevention and disaster reduction system.
Chen Jin, Tang Hong, WU Jianjun, ZHOU Hongmin
This data set is collected from the supplementary information part of the paper: Pei, S.P., Niu, F.L., Ben-Zion, Y., Sun, Q., Liu, Y.B., Xue, X.T., Su,J.R., & Shao, Z.G. (2019). Seismic velocity reduction and accelerated recovery due to earthquakes on the Longmenshan fault. Nature Geoscience. 12. 387-392. doi:10.1038/s41561-019-0347-1. This paper studies the structural evolution process of The Longmenshan fault zone located at a pronounced topographic boundary between the eastern margin of the Tibetan plateau and the western Sichuan basin. With the observations on coseismic velocity reductions and the healing phases, it is found that the healing phase of Wenchuan earthquake fracture zone accelerated significantly in response to the Lushan earthquake. This data set contains 3 tables, table names and content are as follows: Data list: The data name list of the rest tables; t1: Data of the four periods (befor Wenchuan earthquake, after Wenchuan earthquake, before Lushan earthquake, after Lushan earthquake); t2: The average velocities with error in Figure 2 in the paper for Wenchuan earthquake (WCEQ) and Lushan earthquake (LSEQ) area. See attachments for data details: Supplementary information.pdf, Seismic velocity reduction and accelerated recovery due to earthquakes on the Longmenshan fault.pdf.
PEI Shunping
The dataset partially used in the study of paper 2018GC007986 includes S receiver functions derived from 48 permanent stations and 11 stations of a temporary HY array deployed in the northeastern Tibetan Plateau. The dataset as a zipped file contains one folder, two files including NETibet_SRF.QBN and NETibet_SRF.QHD. A spiking deconvolution in the time domain is used to calculate the P and S receiver functions, all the S receiver functions have been visually inspected to remove the bad traces that obviously different from the majority. The dataset is applied to explore the lithospheric structure and understand the mechanism of northeastern expansion and growth of NE Tibetan Plateau.
XU Qiang
The Pan-Third Polar region has strong seismic activity, which is driven by the subduction and collision of the Indian plate, the Arab plate and the Eurasian plate. 3809 earthquakes with Magnitude 6 or larger have occurred in Pan-Third Polar region (north latitude 0-56 degrees and east longitude 43-139 degrees) since 1960. Among them, 59 earthquakes with Magnitude 8 or larger, 689 earthquakes with Magnitude 7.0-7.9 and 3061 earthquakes with Magnitude 6.0-6.9 have occurred. Earthquakes occurred mainly in the foothills of the India-Myanmar Mountains, the Himalaya Mountains, the Sulaiman Mountains, where the India Plate collided with the Eurasian plate, and the Zagros Mountains where the Arab plate collided with the Eurasian plate.
WANG Ji
The data includes earthquakes at various levels across the country from 2300 BC to 2005 AD. There are a total of more than 330,000 catalogs, each of which includes earthquake time, epicenter longitude, epicenter latitude, focal depth, positioning accuracy, and magnitude. This data was first released by the National Seismological Bureau. The China Earthquake Catalog contains a Mapinfo layer (Total_0510Time) and files with the extensions .TAB, .MAP, .DAT, .ID. Their functions are as follows: TAB: the main file, including the table data structure and entity data format fields; MAP: a geographic data file containing map objects; ID: the index file of the graphic object file (MAP); DAT: Form data file.
MA Jin
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