Hadean geodynamics and early Earth environment
Thursday, March 11, 2021 - 11:00
Jun Korenaga, Yale
Jun Korenaga, Yale, will present "Hadean Earth" as part of Andrew Steel's "What is Life and Where Can We Find It" thematic seminar series.
Postdocs are invited to stick around for a Q&A session with Dr. Korenaga after the presentation.
Reconstructing Earth history during the Hadean defies the traditional rock-based approach in geology. Given the extremely limited locality of Hadean zircons, some indirect approach needs to be employed to gain a global perspective on the Hadean Earth. In my talk, two promising approaches are discussed jointly. One is to better constrain the evolution of continental crust, which helps to define the global tectonic environment because generating a massive amount of felsic continental crust is difficult without plate tectonics. The other is to better understand the solidification of a putative magma ocean and its consequences, as the end of magma ocean solidification marks the beginning of subsolidus mantle convection. On the basis of recent developments in these two subjects, along with geodynamical consideration, a new perspective for early Earth evolution is presented, which starts with rapid plate tectonics made possible by a chemically heterogeneous mantle and gradually shifts to more modern-style plate tectonics with a homogeneous mantle. One unique feature of the new hypothesis is its potential to explain the evolution of nearly all components in the Earth system, including the atmosphere, the oceans, the crust, the mantle, and the core, in a geodynamically sensible manner.
This event will be held via Zoom. For access to this lecture, email our events coordinator Alycia Alexander (firstname.lastname@example.org.) If you are employed by the Earth and Planets Laboratory you will receive the Zoom link automatically.