Aleksey Smirnov (GMES) is a co-author on the paper “Paleomagnetic evidence for modern-like plate motion velocities at 3.2 Ga” published in Science Advances on April 22, 2020. This collaborative study (with Harvard University and Yale University) demonstrates that the drifting of tectonic plates (plate tectonics) may have started at least 3.2 billion years ago, earlier than previously thought.
When plate tectonics began
This process may have been underway over 3.2 billion years ago.
Plate tectonics has been the dominant surface geodynamical regime throughout Earth’s recent geological history. One defining feature of modern plate tectonics is the differential horizontal motion of rigid lithospheric plates
The mode and rates of tectonic processes and lithospheric growth during the Archean [4.0 to 2.5 billion years (Ga) ago] are subjects of considerable debate. Paleomagnetism may contribute to the discussion by quantifying past plate velocities.
While plate tectonics have characterized Earth’s geodynamics in recent geologic time, it is unknown whether long-range horizontal motion of lithospheric plates occurred before ~2.7 Ga. Resolving this uncertainty would fundamentally contribute to understanding the formation settings of Earth’s earliest crust and nascent biosphere and the evolution of geodynamics in terrestrial planets in general.
Paleomagnetic evidence for modern-like plate motion velocities at 3.2 Ga
BY ALEC R. BRENNER, ROGER R. FU, DAVID A.D. EVANS, ALEKSEY V. SMIRNOV, RAISA TRUBKO, IAN R. ROSE
Science Advances 22 Apr 2020:
Vol. 6, no. 17, eaaz8670
Archean basalts from the Pilbara Craton, Western Australia record the oldest long-range lithospheric motion identified to date.