Chris Gittins sends along this post by Gavin Schmidt, who writes:
Some editors at Wikipedia have made an attempt to produce a complete record for the Phanerozoic:
But these collations are imperfect in many ways. On the last figure the time axis is a rather confusing mix of linear segments and logarithmic scaling, there is no calibration during overlap periods, and the scaling and baselining of the individual, differently sourced data is a little ad hoc. Wikipedia has figures for other time periods that have not been updated in years and treatment of uncertainties is haphazard (many originally from GlobalWarmingArt).
I think this could all be done better. However, creating good graphics takes time and some skill, especially when the sources of data are so disparate. So this might be usefully done using some crowd-sourcing . . .
In general, I’d give the advice that multiple graphs are a good idea, and that many graphics difficulties come from people trying to come up with some clever method for cramming too much information on to a single plot.
That said, when I think of the challenge of coming up with a single graph representing a time scale of many orders of magnitude, I think of this amazing poster, L’histoire de la Terre et de ses habitants, which cleverly uses nested helixes to display recent centuries on a single unified scale going back billions of years: