The Comprehensive Isoseismal Map of North China

Session: Near-Surface Effects: Advances in Site Response Estimation and Its Applications [Poster]
Type: Poster
Date: 4/28/2020
Time: 08:00 AM
Room: Ballroom
Description: 

The comprehensive isoseismal map shows the maximum intensities of the earthquakes in an area for the period, which provides important information for people to understand earthquake spatial distribution, earthquake strength, geological structure, seismic influence, etc.

In this study, we took the North China Active Block Area as the research area and produced a comprehensive isoseismal map of North China, which provides a basis for the assessment of seismic hazard in North China. We collected all data of earthquakes greater than M4¾, including whose epicenter located in the study area and those produced the affecting intensities greater than V for the area. We digitized isoseismal map of every historical earthquake if it had and built a database using ArcView software. Taking advantage of the function of data management and drawing, we obtained the comprehensive isoseismal map for North China.

The several conclusions can be obtained and listed as follows.

1. Since 1484, 80 percent of areas have experienced intensities greater than Ⅵ in North China.

2. Intensities greater than Ⅶ widely distributed with band, mainly along Huashan front fault, Fen-Wei fault depression zone, Tanlu fault zone and Zhangjiakou-Bohai fault zone, which is consistent with the active structure distribution.

3. Every greater-than-Ⅷ intensity area is only affected by a single strong earthquake. These areas are usually located in the vicinity of epicenter of earthquakes greater than Ms7 with closed elliptical shape.

4. The high intensity areas of strong earthquakes usually match the range of seismic source zone. It indicates that the seismic source zone of great earthquakes (Ms ≥8.0) can be delineated in terms of intensity Ⅸ zone and the delineation of seismic source zone for earthquakes (Ms7.0-7.9) can be done based on intensity Ⅷ zone.

Presenting Author: Yuejun Lyu

Authors