The new model provides a high-resolution understanding of how today’s geophysical landscapes were created and how millions of tons of sediment have flowed to the oceans.
How has sediment transfer and accumulation from lands to oceans affected Earth’s geomorphology? Salles et al. present results from a high-resolution model of surface physiography, validated by independent observations from the geological record, which simulates landscape evolution caused by erosion and deposition over the past 100 million years. Image credit: Salles et al., doi: 10.1126/science.add2541.
“To predict the future, we must understand the past. But our geological models have only provided a fragmented understanding of how our planet’s recent physical features formed,” said Dr. Tristan Salles, a researcher at the University of Sydney.
“If you look for a continuous model of the interplay between river basins, global-scale erosion and sediment deposition at high resolution for the past 100 million years, it just doesn’t exist.”
“So, this is a big advance. It’s not only a tool to help us investigate the past but will help scientists understand and predict the future, as well.”
Using a framework incorporating geodynamics, tectonic and climatic forces with surface processes, Dr. Salles and colleagues created a new dynamic model of the past 100 million years at high resolution (down to 10 km), broken into frames of a million years.
“This unprecedented high-resolution model of Earth’s recent past will equip geoscientists with a more complete and dynamic understanding of the Earth’s surface,” said Dr. Laurent Husson, a researcher at the Institut des Sciences de la Terre.
“Critically, it captures the dynamics of sediment transfer from the land to oceans in a way we have not previously been able to.”
“Understanding the flow of terrestrial sediment to marine environments is vital to comprehend present-day ocean chemistry,” Dr. Salles said.
“Given that ocean chemistry is changing rapidly due to human-induced climate change, having a more complete picture can assist our understanding of marine environments.”
The model will allow scientists to test different theories as to how the Earth’s surface will respond to changing climate and tectonic forces.
Further, the research provides an improved model to understand how the transportation of Earth sediment regulates the planet’s carbon cycle over millions of years.
“Our findings will provide a dynamic and detailed background for scientists in other fields to prepare and test hypotheses, such as in biochemical cycles or in biological evolution,” Dr. Salles said.
The team’s work was published in the journal Science.
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Tristan Salles et al. 2023. Hundred million years of landscape dynamics from catchment to global scale. Science 379 (6635): 918-923; doi: 10.1126/science.add2541
Source : Breaking Science News