New tectonic plate model with boundary regions in darker shading. credit: Dr. Derrick Hesterok, University of Adelaide
New models that show how continents were assembled are providing new insights into Earth’s history and will help provide a better understanding of natural hazards such as earthquakes and volcanoes.
“We looked at current knowledge of the configuration of plate boundary regions and the past formation of continental crust,” said Dr. said Derrick Hesterok, lecturer, Department of Earth Sciences, University of Adelaide, who led the team that produced the new model.
“The continents were assembled a few pieces at a time, like a jigsaw, but each time the puzzle was finished it was cut out and reorganized to form a new picture. Our study helped illuminate the different components.” so that geologists can link the previous images together.
“We found that the plate boundary area is about 16 percent of the Earth’s crust and an even greater proportion, 27 percent, of the continents.”
“Our new model for tectonic plates better explains the spatial distribution of 90 percent of earthquakes and 80 percent of volcanoes over the past two million years, while existing models capture only 65 percent of earthquakes.”
, Dr. Derrick Hesterok, Lecturer, Department of Earth Sciences, University of Adelaide
New models showing Earth’s architecture. credit: Dr. Derrick Hesterok, University of Adelaide
The team produced three new geological models: a plate model, a province model, and an orogeny model.
“There are 26 orogenies – the process of mountain formation – that have left an imprint on the current architecture of the crust. Many, but not all, of these are related to the formation of the supercontinent,” said Dr. Hesterok.
“Our work allows us to update maps of tectonic plates and the formation of continents found in classroom textbooks. These plate models that have been gathered from topographic models and global seismology have not been updated since 2003. “
The new plate model includes several new microplates including the Macquarie Microplate which lies south of Tasmania and the Makar Microplate which separates the Indian and Australian plates.
“To further enrich the model, we added more precise information about the boundaries of the deformation fields: previous models showed these as discrete regions rather than detailed regions,” said Dr. Hesterok said.
“The greatest changes to the plate model have occurred in western North America, with the boundary often along the drawn Pacific Plate such as the San Andreas and Queen Charlotte Faults. But the newly delineated boundary is roughly 1500 compared to the previously drawn narrow area. km is wider.
“The other big change is in Central Asia. The new model now includes all deformation zones north of India as the plate makes its way into Eurasia.
A story told by continents. credit: Dr. Derrick Hesterok, University of Adelaide
published in the journal Earth Science reviewThe team’s work provides a more accurate representation of Earth’s architecture and has other important applications.
“Our new model for tectonic plates better explains the spatial distribution of 90 percent of earthquakes and 80 percent of volcanoes over the past two million years, while existing models capture only 65 percent of earthquakes,” said Dr. Hesterok said.
“The plate model can be used to improve models of risk from geohazards; the orogeny model helps to understand geodynamic systems and better model the evolution of the Earth and the province model can be used to improve prospecting for minerals.” can be done for.
References: Derrick Hesterok, Jacqueline A. Halpin, Alan S. Collins, Martin Hand, Korn Kramer, Matthew G. “New Maps of Global Geological Provinces and Tectonic Plates”, by Gard and Stijn Glory, 31 May 2022, Earth Science review,
DOI: 10.1016/j.earscirev.2022.104069
The work involved researchers from the universities of Adelaide, Tasmania, Nevada-Reno and Geosciences Australia.
