Humans have walked the Earth for 190,000 years, a mere blip in Earth's 4.5- billion-year history. A lot has happened in that time. Earth formed and oxygen levels ...
Earth Earth's Geologic
Chart. Click here (PDF or JPG) to download the latest version (v2016/04) of the International Chronostratigraphic Chart. The explanatory article was published in ...
Note that the compilers are still accepting comments on the overall content of