Starting from version 2012 = the version distributed August 2012 at 34th IGC Brisbane), this change log lists: Changes ICS chart v.2013/01 Changes ICS chart v.2013/Episodes Changes ICS chart v.2014/02 Changes ICS chart v.2014/10 Changes ICS chart v.2015/01 Changes ICS chart v.2016/04 = the version distributed at 35th IGC Cape Town Changes ICS chart v.2016/10 Changes ICS chart v.2016/12 Changes ICS chart v.2017/02 = actual version GSSP's added: 2016/10 - Paleogene: Chattian Stage: GSSP added as it was ratified by IUGS (1-10-2016) 2016/04 - Cretaceous: Albian stage: GSSP added as it was ratified by IUGS (8-4-2016) 2015/01 - Jurassic: Toarcian Stage: GSSP added as it was ratified. 2013 - Cretaceous: Santonian Stage: GSSP added as it was ratified. GSSA's changed/dropped: 2015/01 - base Cryogenian: changed to ~720 Ma (was 850 Ma, an Episodes paper by the subcommission in preparation). - In the outer right column, the graphic thickness of Cryogenian is reduced and that of the Tonian increased. 2016/04 - With the tuned age of the base Cryogenian being established, it is no-longer a ratified GSSA and the icon is dropped. Numeric Ages altered: 2017/02 - Paleogene: Base of Chattian: The numeric age is updated to that at the ratified GSSP (27.82 Ma; Nanno et al. exp. 2017; by request of Simonetti Monechi) 2016/12 - Permian-Triassic boundary: 251.902 +/- 0.024 Ma (Burgess et al., 2014, PNAS) - by request of SPS (Shen Shuzhong) and STS (Mark Hounslow) 2016/12 - Permian: Base of Lopingian (Wuchiapingian): 259.1 +/- 0.5 Ma (Zhong et al., 2014, Lithos) - by request SPS (Shen Shuzhong) 2016/12 - Permian: Base of Guadalupian (Roadian): 272.95 +/- 0.11 Ma (Wu et al.,2016, Palaeo-3) - by request of SPS (Shen Shuzhong) 2014/10 - Neogene: base Tortonian: 11.63 (cf. GTS2012; incorrectly was 11.62 in previous ICS versions) 2014/10 - Paleogene: base Priabonian: 37.8 (cf. GTS2012 incorrectly was 38.0 in previous ICS versions) 2014/10 - Paleogene: base Bartonian: 41.2 (cf. GTS2012; incorrectly was 41.3 in previous ICS versions) 2014/10 - Silurian: base Rhuddanian: 443.8 (cf. GTS2012; incorrectly was 443.4 in previous ICS versions) 2014/02 - Pleistocene: base Calabrian: 1.80 (removed 3rd decimal) - Argumentation to deviate from GTS2012: Gibbard & Head, 2009 2014/02 - Pleistocene: base Gelasian: 2.58 (removed 3rd decimal) - Argumentation to deviate from GTS2012: Gibbard & Head, 2009 2013 - Triassic: base Norian: ~227 2013 - Triassic: base Carnian: ~237 2013 - Base Triassic: base: 252.17 +/- 0.06 2013 - Permian: base Changhsingian: 254.14 +/- 0.07 2013 - Permian: base Wuchiapingian: 259.8 +/- 0.4 2013 - Permian: base Capitanian: 265.1 +/- 0.4 2013 - Permian: base Wordian: 268.8 +/- 0.5 2013 - Permian: base Roadian: 272.3 +/- 0.5 2013 - Permian: base Kungurian: 283.5 +/- 0.6 2013 - Permian: base Artinskian: 290.1 +/- 0.26 2013 - Permian: base Sakmarian: 295.0 +/- 0.18 2013 - Permian: base Asselian: 298.9 +/- 0.15 --------- Based on SPS Permian chart and communication with Triassic subcommission (S. Finney) 2013 - BASE OF CRETACEOUS, BASE OF CARBONIFERIUOUS, BASE OF CAMBRIAN, the ages for these three also appear as top of Jurassic, Devonian, Ediacaran in the chart layout. the ages reported for the top are _exactly_ the same as for the base (e.g. ~ 145.0 for Base Cretaceous, not +-0.1) Typesetting changes: 2016/04 Upper and Middle Pleistocene: placeholder subseries name in Stages column set in italics rather than regular font ======================== Text: - Authorship of version of chart changed: DAT Harper has taken over role of SC Finney in ICS executive board (as per 35th IGC Capetown ICS business-meeting and IUGS assembly) - TWO TIMES: IN THE FIRST LINE AND IN THE THIRD LINE 2016/10 - reordered ammended the ages/subcommissions to be chronological (LP, C, T, P, PreC) 2013 - Permian ages 2014/02 - Lower Pleistocene ages 2017/02 - Upper Paleogene ages added to Triassic and Cretaceous ones as deviating from 'A Geological Time Scale 2012' communicated status 2014/02 - To cite: Cohen et al. (2013) Episodes reference added. Graphic: - 'Systems' cells of first column slimmed down to match the width in the second and third column - Vertical and horizontal centering of names in their cells checked and fixed Adobe-illustrator file: - Background layer (not displayed as visible) contained 'made invisible' logos from 2012 congres and sponsor. These are deleted now. - Added the deep URL in the lowerright corner of the chart. - Added a line 'The URL to this chart is found below.' to the first paragraph of the text. - line spacing of the blank lines set to 7 pt, wheras the main text is in 9 pt font.