At least since Mallet (1858) seismicity maps have been a way of showing earthquake activity, but, because earthquake size varies greatly, it is difficult to provide an accurate representation of the spatial variation of total seismic energy or moment release. The most common approach, using for each earthquake a single geometric figure of varying size, creates substantial overlap between large symbols. To reduce overlap and provide a more distinctive gradation, I propose a family of symbols in which size and shape vary together, from polygonal to star shaped as their size increases. Two functions determine how symbol size and shape...

First Page Preview

First page PDF preview
You do not currently have access to this article.