Research : ‘Asteroid impact stored proof of life in glasses on earth’

Scientists have found that asteroid impacts not only result in formation of rocks and soil, but also form molten glass on cooling. Pete Schultz, Brown University geologist along with his colleagues have discovered fragments of leaves and other organic compounds lodged inside glass created by ancient impacts in Argentina. They said that analysis of biodata encapsulated in molten glass from millions of years will help provide information about the climate and life forms of the ancient Earth.

“One of those impacts, dated to around three million years ago, coincides with the disappearance of 35 animal species as reported earlier,” said Pete Schultz, a geologist from Brown University in Rhode Island who led the study.

The discovery also suggests that impact glasses could be a good place to look for signs of ancient life on Mars. “We know these were major impacts because of how far the glass is distributed and how big the chunks are. These glasses are present in different layers of sediment throughout an area about the size of Texas,” Schultz noted. “These impact glasses preserve plant morphology from macro features all the way down to the micron scale. It is really remarkable,” Schultz added.

The glass samples contain centimetre-size leaf fragments, including intact structures like papillae, tiny bumps that line leaf surfaces.

Chemical analysis of the samples also revealed the presence of organic hydrocarbons, the chemical signatures of living matter.

To understand how these structures and compounds could have been preserved, the lab experiments showed that plant material was preserved when the samples were quickly heated to above 1,500 degrees celsius – at the time of the asteroid or comet impact.

The soil conditions in Argentina that contributed to the preservation of samples in this study are not unlike soils found on Mars.

Agencies/Canadajournal