对多数地区，等震线略具狭长的形状，经验点椭圆模型可以减小点源模型和断层破裂模型的系统偏差。

For most of the regions, isoseismals are of somewhat elongated shape. The empirical point-ellipse model can reduce systematic deviation of point-source and fault-rupture models.

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上部墙体潜在破裂面形状与“0。”

The potential fracture plane at upper wall is similar to "0."

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