Scientists have discovered 2.7 billion-year-old gas bubbles in volcanic rock formations in Western Australia and this matters because it provides deep insights into the atmospheric conditions of ancient Earth.
How are these gas bubbles formed?
When a volcano erupts, it spews out molten rock from the core of Earth, called lava. The lava either erupts in violent blasts, or cascades down the volcano like a sludgy waterfall, in case of a non-explosive eruption. The latter is known as lava flow. When lava flow solidifies over the years, it forms igneous rock formations, often trapping gas bubbles. These bubbles can be preserved for billions of years, trapped in the rocks.
The bubbles, discovered along the Beasly River in Western Australia were formed due to Mafic or Basaltic lava flows at sea level, solidified through billions of years.
So what do these gas bubbles reveal?
Analyzing their size using differential measurement techniques revealed that ancient Earth's atmosphere was much thinner, rich in auxiliary greenhouse gases and that the air pressure was half of what it is today.
The Earth was formed 4.5 billion years ago, and 2.7 billion years ago, it was still in its formative stages, with single celled organisms and no atmospheric oxygen. A lot has changed since then.
Sanjay Som, the CEO of Settle-based non profit organisation 'Blue Marble Space', and the leader of the research team said that the studies contradict long-standing notions of the Earth's ancient atmosphere, which was believed to be thicker to make up for a faint sun. (The Young-Faint Sun Paradox)
According to Som, the findings are important because they demonstrate that planetary environment completely different than modern Earth can sustain life on its surface.
"Life doesn't need conditions like modern Earth to survive and thrive. This is important in our quest for habitable environments in extra-solar planets," said Som.
The findings, published in Nature Geoscience, provide an important clue to scientist about ancient Earth's history, and also create newer avenues for the quest of life on other planets with a similar atmosphere. The magnitude of the implications is massive.
“People will need to rewrite the textbooks.” Som added.