/newsroom/taxonomy/term/427/all en /newsroom/channels/news/billion-year-old-lake-deposit-yields-clues-earths-ancient-biosphere-288081 <p>A sample of ancient oxygen, teased out of a 1.4 billion-year-old evaporative lake deposit in Ontario, provides fresh evidence of what the Earth’s atmosphere and biosphere were like during the interval leading up to the emergence of animal life. </p> Tue, 17 Jul 2018 18:05:54 +0000 justin.dupuis@mcgill.ca 58963 at /newsroom /newsroom/channels/news/mining-ancient-ores-clues-early-life-219461 <p>An analysis of sulfide ore deposits from one of the world’s richest base-metal mines confirms that oxygen levels were extremely low on Earth 2.7 billion years ago, but also shows that microbes were actively feeding on sulfate in the ocean and influencing seawater chemistry during that geological time period.</p> Mon, 10 Dec 2012 17:48:22 +0000 christopher.chipello@mcgill.ca 12313 at /newsroom