CAJ | 학술논문

地震发生后，根据地震参数快速设计和显示出地震影响场，初步确定较为合理的地震烈度分布范围，对于政府及时了解灾情和损失分布非常重要。收集、整理甘肃地区实际地震等震线图，将其与现有地震烈度衰减关系生成的理论烈度图进行统计对比分析，并与研究区 DEM(数字高程模型)相结合，研究地形因子对烈度影响场分布的影响。结论表明：不同震级档之间，实际与理论地震烈度分布之间规律不同；分区研究发现，除极震区外，祁连山-河西走廊地区外圈等震线理论长短轴以及面积均大于实际，甘东南地区规律则与之相反。地形因子对烈度影响场的影响是明显的，海拔越高，烈度越高；山顶点处烈度高于周围地区；相对震中而言，坡度大的地方烈度衰减快，反之则烈度衰减慢。
지진발생후，근거지진삼수쾌속설계화현시출지진영향장，초보학정교위합리적지진열도분포범위，대우정부급시료해재정화손실분포비상중요。수집、정리감숙지구실제지진등진선도，장기여현유지진열도쇠감관계생성적이론열도도진행통계대비분석，병여연구구 DEM(수자고정모형)상결합，연구지형인자대열도영향장분포적영향。결론표명：불동진급당지간，실제여이론지진열도분포지간규률불동；분구연구발현，제겁진구외，기련산-하서주랑지구외권등진선이론장단축이급면적균대우실제，감동남지구규률칙여지상반。지형인자대열도영향장적영향시명현적，해발월고，열도월고；산정점처열도고우주위지구；상대진중이언，파도대적지방열도쇠감쾌，반지칙열도쇠감만。
The Gansu earthquake emergency command system was founded during the Tenth Five-year Plan by the Earthquake Administration of Gansu province.It was reviewed and accepted by the China Earthquake Administration and was enacted in 2007.With this system,we can first obtain the seismic intensity distribution and influence region according to the local intensity atten-uation relationship and then quickly estimate earthquake casualty loss according to the seismic in-tensity distribution.We can then propose emergency measures and rescue plans and assist in deci-sion-making for earthquake relief headquarters.Damage degrees of construction and lifeline engi-neering,including water supply,power supply,heat supply,air supply,transportation,and com-munication systems,differ among affected areas.Moreover,secondary disaster influences also dif-fer,as well as casualties and financial loss.The seismic influence field examines the influence areas by different damage intensities.After an earthquake,designing and presentation of the influence field according to the earthquake parameters and formulating a relatively reasonable seismic inten-sity distribution range is very important for government investigation of the situation and damage distribution.The feasibility of the earthquake influence field will directly affect the rationality and accuracy of the assessment results.The calculation results of the existing evaluation system differ significantly from the actual results;therefore,the influence of the relief results also differs.The attenuation relationship model makes use of the large-scale nationwide western attenuation rela-tionship,the Gansu attenuation relationship of seismic intensity,and modified seismic intensity af-fecting the field model of the Gansu area in the Gansu earthquake emergency command technolo-gy system module to make fast judgment of the seismic influence field and heavy disaster area. However,differences occur in the actual attenuation relationship among areas and magnitudes due to different source characteristics,propagation media,and site conditions.In this paper,isoseismal line maps of actual earthquakes in the Gansu region were collected and compared with theoretical intensity generated by the attenuation relationship.In addition,the influence of terrain factors on the intensity influence field in study area was analyzed by using the digital elevation model (DEM).Conclusions show that the actual and theoretical seismic intensity distribution at each magnitude level differed.In general,the theoretical epicentral area is relatively small at the 5.0~5.2 level and shows subarea characteristics at the 5.3~5.9 level,whereas the theoretical intensity distribution is close to actual results at the 6.8~7.5 level.The subarea study shows that the outer major and minor axes and area of theoretical seismic influence field are greater than those of the actual values in the Qilian Mountains- Hexi Corridor region.However,except for the meizoseis-mal area,performance in the southeast region of Gansu is opposite.The impact of terrain factors on the intensity influence field is obvious.Higher altitude relates to higher intensity,and the inten-sity at the summit point is higher than that in the surrounding region.A greater slope to the epi-center relates to faster attenuation of the intensity and vice versa.There are obvious differences between actual and theoretical seismic influence fields,which should be considered in practical ap-plication.We should adjust the distribution of theoretical intensity by considering local terrain, landform,and site type to obtain a more reliable post-earthquake assessment outcome.Further-more,quantification of the site influence would better serve earthquake emergency response and rescue.