摘要
Based on relocating the Jiujiang-Ruichang earthquake sequence which occurred on November 26, 2005 in Jiangxi Province with the double-difference （DD） algorithm and master event technique, the paper discusses the focal mechanism of the main shock （MsS.7） and the probable seismo-tectonics. The precise relocation results indicate that the average horizontal error is 0.31kin in a EW direction and 0.40kin in a NS direction, and the average depth error is 0.48kin. The focal depths vary from 8kin to 14kin, with the predominant distribution at 10kin - 12kin. The epicenter of the main shock is relocated to be 29.69^oN, 115.74^oE and the focal depth is about 10.Skin. Combining the predominant distribution of the earthquake sequence, the focal mechanism of the main shock and the tectonic conditions of N-E- and NW-strike faults growth in the seismic region, we infer that the main shock of the earthquake sequence was caused by a NW striking buried fault in the Rnichang basin. The nature of seismic faults needs to be further explored.
Based on relocating the Jiujiang-Ruichang earthquake sequence which occurred on November 26,2005 in Jiangxi Province with the double-difference(DD)algorithm and master event technique,the paper discusses the focal mechanism of the main shock(M_S5.7)and the probable seismo-tectonics.The precise relocation results indicate that the average horizontal error is 0.31km in a EW direction and 0.40km in a NS direction,and the average depth error is 0.48km.The focal depths vary from 8km to 14km,with the predominant distribution at 10km～12km.The epicenter of the main shock is relocated to be 29.69°N,115.74°E and the focal depth is about 10.8km.Combining the predominant distribution of the earthquake sequence,the focal mechanism of the main shock and the tectonic conditions of NE-and NW-strike faults growth in the seismic region,we infer that the main shock of the earthquake sequence was caused by a NW striking buried fault in the Ruichang basin.The nature of seismic faults needs to be further explored.
基金
This research was supported by the Joint Earthquake Science Foundation (A07124)
the project of"Application of Digital Seismic Data to Short-impending Tracing"of China Earthquake Administration (120602-06-114)
