New Study Reveals Earth Formed from Dry Materials, Water Arrived Late in the Planet’s Formation
A recent study conducted by scientists at Caltech has shed light on the formation of the early Earth. The research suggests that the planet was formed from hot and dry materials, indicating that water arrived on Earth late in its formation process. This finding challenges previous theories about how terrestrial planets are formed.
The study focused on analyzing magmas from different layers of the Earth’s interior, which provided valuable insights into the planet’s formation. These magmas contain chemical signatures that reveal the timing and nature of the materials that came together to create Earth.
According to the team of researchers, the early Earth accreted from hot and dry materials, suggesting that water, which is essential for the evolution of life, arrived late in the planet’s history. This finding has significant implications for our understanding of how Earth’s formation impacted the development of life on the planet.
The study, which involved an international team of scientists, was led by Francois Tissot, assistant professor of geochemistry at Caltech, and Yigang Zhang of the University of Chinese Academy of Sciences. The research findings were published in the journal Science Advances, with Caltech graduate student Weiyi Liu as the paper’s first author.
To study the Earth’s formation, scientists analyzed rocks from deep within the Earth’s interior. These rocks can naturally make their way to the surface in the form of lavas, providing valuable information about the planet’s composition.
By examining magmas originating from different depths within the Earth, researchers were able to understand the different layers of the planet and their chemical compositions. The study found that the early Earth was primarily composed of dry, rocky materials, lacking volatiles like water.
In contrast, samples from the upper mantle revealed a higher proportion of volatiles, suggesting that significant additions of life-essential volatiles, including water, only occurred during the final stages of Earth’s formation. This late arrival of water challenges previous theories about the planet’s formation and has important implications for our understanding of terrestrial planet formation.
The findings of this study contribute to the ongoing debates and shifts in our understanding of planet formation. It also provides valuable insights into the building blocks of other terrestrial planets, such as Mercury and Venus.
Tissot emphasizes the importance of studying the inner solar system, including Venus and Mercury, to better understand the formation of terrestrial planets. He highlights the need for future missions to these planets in order to expand our knowledge of planet formation and the potential for extraterrestrial life.
The study was funded by the Chinese Academy of Sciences, the National Science Foundation, a Packard Fellowship for Science and Engineering, the Heritage Medical Research Institute, and Caltech.
As scientists continue to uncover new insights into the formation of our planet, these findings open up new avenues for exploration and understanding of Earth’s geological history.