珠江三角洲地区未来地震危险性预测

SEISMIC HAZARD PREDICTION IN THE PEARL RIVER DELTA AREA

珠江三角洲地区的基岩地质、新构造运动、航磁和重力资料都反映ＮＥＥ向是最主要的构造方向，ＮＥＥ向的恩平－海丰一线把研究区分成南北两区。在地震相对活跃阶段，ＭＳ≥５级地震和地震相对平静阶段的ＭＬ≥２０级地震都具有南、北分区的特点。未来的地震活动仍然是南区活动较强北区活动较弱。推测认为，近５年内不论南区抑或北区，都将会发生ＭＬ≥４０级地震，但两区发生ＭＬ≥５级地震的可能性不大。

The NEE striking faults are the main active fults in the Pearl River Delta area.The study region may be divided into the south part and north part with a Haifeng-Enping line in the direction of NEE.In the north part of the study region, there was less seismicity in the basin and its vicinity.For the south part of the region,the seismicity was more active in the uplifted area rather than in the basin .In accordance with the seismicity,there are some M L≥4 0 earthquake events in the south and north part in next 5 years,but events with M S≥5 might not be occurred in the two parts.