**UoP maths seminar (2013-14)**

**Power law crossovers in the size distributions of catastrophic events.**

*Speaker*: James Burridge

*Venue*: Wednesday 16th October 2013, 2pm, LG2.04a (refreshments provided)

*Abstract*: There is considerable field evidence that the size distributions of a range of catastrophic events, including disease outbreaks, earthquakes, avalanches, landslides and forest fires all exhibit power-law scaling behaviour. In other words, the probability of observing an event of size *x* is proportional to *x*^{-b} for some positive *b*. Often a single power law is sufficient to describe the event size distribution which then appears as a straight line on log-log axes. However, sometimes a "kink" appears separating two power law regions. The fact that this kink is exhibited in multiple phenomena suggests that the underlying mechanism might have a single universal explanation. Over the past year I have been attempting to find one. In this talk I will present my results.