Hence the Be prepared for earthquakes shirt, deformation or any kind of movements in the past 2 billion years or more. The geologists assign an area as hazardous or susceptible to earthquakes on the basis of the active fault lines in an area. Mainly the faulting is observed along the plate margins. But shield rocks are generally exposed on the flat plains in the central areas of plates. Shields are normally nucleus of continents surrounded by folded Precambrian rocks. Shields lack mountains because of non-involvement in the orogeny which involves faulting and uplifting. Hence the mountains formed during the last stages of tectonic activities at the shields are eroded away at the passage of time. The shield is not totally flat generally but shows a very gentle convex upward topography.
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