1. THORS ontology updated to align with OWL-Time (instead of ISO 19108). 2. GTS ontology updated to use sam-lite (instead of OWL implementation of ISO 19156)
with a lightweight SOSA alignment 3. atialSP data uses GeoARQLSP (instead of OWL implementation of ISO 19107)
2017-02-22 Added additional collections for eras of each rank; classified rank-based collections using XKOS; cleaned out legacy Base* instances that did not have links; renamed [GS]SP* individuals to *SP; removed all boundaries as TopConcepts, leaving on PreCambrian and Phanerozoic as TopConcepts
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)
Added informal definition of chronometric temporal reference system - Millions of
years, counting backwards from 1950
See <http://stratigraphy.org/ICSchart/ChangeLog2012-2013-2014-2015-2016-2017.txt>
for changes from prior versions
