Researchers have made an amazing discovery after analyzing ancient grains of crystal in Australia. While scientists believed that Earth was entirely covered with water four billion years ago, researchers found that this might not have been the case, according to a CNN report.
An analysis of chemicals found in the crystal revealed that the molten rock in which they were formed had come into contact with fresh water. The study found that the existence of freshwater indicates that at least part of the Earth was covered in dry land, according to CNN.
“By examining the age and oxygen isotopes in tiny crystals of the mineral zircon, we found unusually light isotopic signatures as far back as four billion years ago,” Hamed Gamaleldien, the lead study author, said in a press release, according to CNN. “Such light oxygen isotopes are typically the result of hot, fresh water altering rocks several kilometres below Earth’s surface.”
The lead author explained that the existence of fresh water in ancient times could only be explained by the presence of dry land. “We have two important things here. We have discovered the earliest evidence of fresh water and representative evidence for dry land above the sea,” Gamaleldien said. (RELATED: Study: Science May Have Been Wrong About The Origins Of Life On Earth)
This revelation not only indicates the existence of dry land but also that life could have originated less than 600 million years after the planet was formed, the report noted.
“This discovery not only sheds light on Earth’s early history but also suggests … landmasses and freshwater set the stage for life to flourish within a relatively short time frame — less than 600 million years after the planet formed,” study coauthor Hugo Olierook said.
Gamaleldien explained that it was not possible to ascertain whether large landmasses existed during this time period. However, it does indicate that there was at least some dry land above sea level, according to CNN. Moreover, fresh water would have likely originated as rainfall, which would have provided the conditions for the origin of life on Earth.
“The main novelty of the new paper is concluding that rainwater means the rocks were (on land) … rather than submarine,” John Valley, a professor of geoscience at the University of Wisconsin-Madison, said in the press release.
