// cpt-city: wkp/strat/periods (cpt)
//
// colours from the Wikigeologic scales, dates (MYa)
// from wikipedia pages
//
// author: Sémhur
// copyright: Creative commons attribution share-alike 3.0 unported
// year: 2010
// url: https://phillips.shef.ac.uk/pub/cpt-city/wkp/strat
#declare periods =
color_map {
  [0.00000 color rgbf <0.9961,0.9961,0.8941,0.0000>]
  [0.00477 color rgbf <0.9961,0.9961,0.8941,0.0000>]
  [0.00477 color rgbf <0.7843,0.9216,1.0000,0.0000>]
  [0.04249 color rgbf <0.7843,0.9216,1.0000,0.0000>]
  [0.04249 color rgbf <0.9922,0.7529,0.3216,0.0000>]
  [0.12085 color rgbf <0.9922,0.7529,0.3216,0.0000>]
  [0.12085 color rgbf <0.7725,0.8980,0.2784,0.0000>]
  [0.26845 color rgbf <0.7725,0.8980,0.2784,0.0000>]
  [0.26845 color rgbf <0.8863,0.9569,0.8784,0.0000>]
  [0.36827 color rgbf <0.8863,0.9569,0.8784,0.0000>]
  [0.36827 color rgbf <0.4196,0.0039,0.4902,0.0000>]
  [0.46310 color rgbf <0.4196,0.0039,0.4902,0.0000>]
  [0.46310 color rgbf <0.9412,0.2510,0.1569,0.0000>]
  [0.55166 color rgbf <0.9412,0.2510,0.1569,0.0000>]
  [0.55166 color rgbf <0.4039,0.6706,0.6275,0.0000>]
  [0.66273 color rgbf <0.4039,0.6706,0.6275,0.0000>]
  [0.66273 color rgbf <0.7961,0.5490,0.2157,0.0000>]
  [0.76753 color rgbf <0.7961,0.5490,0.2157,0.0000>]
  [0.76753 color rgbf <0.7020,0.8863,0.8157,0.0000>]
  [0.81864 color rgbf <0.7020,0.8863,0.8157,0.0000>]
  [0.81864 color rgbf <0.0000,0.5725,0.4392,0.0000>]
  [0.90092 color rgbf <0.0000,0.5725,0.4392,0.0000>]
  [0.90092 color rgbf <0.2510,0.5216,0.1294,0.0000>]
  [1.00000 color rgbf <0.2510,0.5216,0.1294,0.0000>]
}