Ancient lava bubbles reveal conditions on primordial Earth

May 12, 2016 at 3:44 pm

WASHINGTON: Tiny bubbles that formed inside volcanic rock 2.7 billion years ago are providing big insights into the conditions on primordial Earth.

Scientists said an analysis of gas bubbles trapped in ancient basalt rock that formed from ancient lava flows in western Australia showed the planet back then possessed a much thinner atmosphere, with air pressure half of what it is today.

That finding contradicts a long-held notion that Earth then had a thicker atmosphere to compensate for a fainter sun, with sunlight about 15 percent dimmer. The sun is slowly brightening over time, part of a star’s natural evolution.

Earth formed about 4.5 billion years ago. The planet 2.7 billion years ago was still much different than it is today.

In addition to the fainter sun, the air lacked oxygen, the moon was closer so tides were stronger, Earth spun more quickly so days were shorter, and the only life forms were single-cell microbes, said study leader Sanjoy Som, CEO of Seattle-based Blue Marble Space, a nonprofit organization focusing on space science research, education and public outreach.

The findings demonstrate that “a planetary environment completely different than modern Earth can sustain life on its surface,” said Som, who worked on the study while at the University of Washington​ and is now based at NASA’s Ames Research Center in California.

“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,” Som added.

The scientists used sophisticated scanning technology to analyze the size and distribution of bubbles within the ancient lava rock found along the shores of Australia’s Beasley River that solidified at sea level.

Lava flows cool rapidly from top and bottom, with bubbles trapped at the bottom being smaller than those at the top. The size difference in these bubbles provided a record of the atmospheric pressure pushing down on the molten rock as it cooled, the researchers said.

The findings suggest Earth’s atmosphere was rich in greenhouse gases.

“This study doesn’t yield direct knowledge about the air composition,” Som said. “Nonetheless, because most of the air pressure is nitrogen, and you needed greenhouse gases to compensate for a faint sun, methane – a powerful greenhouse gas – was a likely important constituent, as well as water vapor – another powerful greenhouse gas.”

The research was published in the journal Nature Geoscience.

Leave a Reply

Your email address will not be published. Required fields are marked *

Recent News

No need to lecture us on relig
ISLAMABAD – Foreign Office on Wednesday summoned senior US officials and lodged a strong after Washington added Pakistan to its blacklist of countries violating religious freedom. According to di...
December 13, 2018 Read More
PM forms committee for inquiry
ISLAMABAD: Prime Minister Imran Khan on Wednesday ordered constitution of a fact-finding committee for an inquiry against managing directors (MDs) of Sui Northern Gas Pipelines Limited (SNGPL) and Sui...
December 13, 2018 Read More
if NAB is being used to pressu
Addressing a National Assembly session, Abbasi said, “Opposition Leader was arrested and till date a case could not be formed against him. Accountability institutions are being used to exert pressu...
December 13, 2018 Read More
Army chief Bajwa witnesses ong
Chief of Army Staff (COAS) General Qamar Javed Bajwa witnessed the ongoing Pak-China International Air Exercise Shaheen-VII at an operational air base of Pakistan Air Force (PAF) in Karachi on Wednesd...
December 13, 2018 Read More
IHC orders removal of Zulfi Bu
ISLAMABAD: The Islamabad High Court on Wednesday ordered removal of name of Zulfi Bukhari, Prime Minister's Adviser on Overseas Pakistanis, from the Exit Control List (ECL). A division bench of the...
December 13, 2018 Read More
Pakistan celebrates 71 years o
ISLAMABAD: The nation celebrated 71st Independence Day today (Tuesday) with traditional fervour and enthusiasm. All major public and private buildings, roads and avenues were decorated with illumin...
August 14, 2018 Read More
President, caretaker PM felici
ISLAMABAD: President Mamnoon Hussain and caretaker Prime Minister Justice (retd) Nasir-ul-Mulk extended heartiest felicitations to all Pakistanis on the occasion of Independence Day. President Mamn...
August 14, 2018 Read More
Imran Khan felicitates Nation
Islamabad : Chairman Pakistan Tehreek-e-Insaf (PTI) Imran Khan on Tuesday felicitated the nation on Independence Day as he vowed to realise Quaid-e-Azam Muhammad Ali Jinnah and Allama Iqbal’s visio
August 14, 2018 Read More
epaper fold