GMPV1.1/GD2.6Origin, evolution of Earth's crust and the formation of a habitable planet (co-sponsored by the European Association of Geochemistry (EAG)) (co-organized)
|Co-Conveners: B. Dhuime , J. van Hunen , J. Tarduno|
Although the Earth’s crust represents the most accessible silicate reservoir for study, geological samples from the first 500 millions years of Earth’s history are exceedingly rare. As a result, there are still many outstanding questions regarding the composition of Earth’s earliest crust, the dynamics of its formation, and how long it persisted after Earth's accretion. The present-day continental crust and the depleted upper mantle are often considered as complementary reservoirs, and it has been widely believed that that the continental crust has grown from the depleted mantle. Questions of when and how continental crust was generated and how much volume of this crust existed through time, however, remain a matter of great debate, in part because different rocks and mineral types preserve different records. New perspectives are rising from the development of new geochemical tracers, the improvement of analytical techniques, and the inclusion of extensive databases.
The evolution of Earth during the Hadean and Archean, and its relationship to the development of life, remains a frontier research area where the most advanced field and analytical techniques must be harnessed to glean details from the ancient geologic record. The period also provides our best model for understanding the potential development of habitable conditions on exoplanets.
This session will explore how direct observations from the rock record, insights from theoretical models, and experimental results can be used to provide constraints on the origin and evolution of the Earth’s continental crust. We welcome contributions that may address the following issues: geodynamic conditions of crust formation, composition of the crust through time, the implications of a non-chondritic Earth on crustal growth models, rates of crust generation and destruction through time, mechanisms of crust formation and stabilization, sources of water for the early Earth, constraints on greenhouse gases in the early atmosphere, tectonic processes in the crust and mantle, heat loss and style of mantle convection, early development of the core and geodynamo, the relationship between melt production and ocean/atmospheric development, evidence for early life, and constraints on the nature of near surface environments.