Ancient crystals reveal the earliest evidence of fresh water, scientists say

A new analysis of ancient grains of crystal from the Australian outback suggests Earth had dry land and fresh water around 4 billion years ago. Chemical clues contained in the crystals revealed that the rocks in which they originated came into contact with fresh water during their formation. This finding indicates that the Earth’s water cycle was operating at that point in time. The presence of fresh water and dry land could explain the origins of life on Earth within a relatively short time frame. The study used zircon crystals to explore Earth’s early history.