The Earth's Early Atmosphere
Chemistry: AQA GCSE Higher, topic 9.1.2
The Earth's Early Atmosphere
The Earth was formed roughly 4.6 billion years ago. We don't have much evidence from that long ago, but the common view (consensus view) among scientists is:
Age of the volcanoes
- Highly active volcanoes were littered across the Earth's surface for the first billion years of its existence.
- The frequent eruptions of these volcanoes resulted in the release of lots of carbon dioxide (as well as smaller amounts of gases such as water vapour, methane, ammonia and nitrogen).
- Scientists think carbon dioxide dominated the early atmosphere in a similar way to modern-day Mars.
Reduction of carbon dioxide levels
- Levels of atmospheric nitrogen accumulated steadily.
- The oceans were formed as a result of the water vapour condensing.
- The formation of the oceans caused a significant reduction in carbon dioxide levels in the atmosphere.
- Carbonate precipitates were produced by reactions between the dissolved carbon dioxide and seawater. These precipitates were deposited as sediment.
Test yourself on The Earth's Early Atmosphere
Approximately how many years ago did the Earth form?
According to scientists, which gas dominated the Earth's early atmosphere, much like Mars's atmosphere today?
What gases were released by intense volcanic activity into the Earth's early atmosphere?
The Earth's Early Atmosphere
The formation of oceans resulted in the removal of large amounts of what substance from the atmosphere?