1. 
   isoseismal
   isoseismal, isoseismic 1. Connecting points on a map at which the intensity of an earthquake-shock is the same. 2. A line connecting points at which the intensity of an earthquake was felt equally or a line on a chart or map connecting points of equal earthquake intensity.
   Found op http://www.wordinfo.info/words/index/info/view_unit/2656/2
   
   
2. 
   isoseismal
   isoseismal. A contour or line on a map bounding points of equal intensity for a particular earthquake.
   Found op http://www.sciencemaster.com/physical/item/earthquake_glossary.php
   
   

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