Chondritic mercury isotopic composition of Earth and evidence for evaporative equilibrium degassing during the formation of eucrites

Mercury isotopes were measured in a suite of terrestrial lavas, including basaltic, trachytic, and granitic igneous lavas. Hg isotopes are also presented on a suite of chondritic meteorites and eucrite meteorites. The Hg isotopes in terrestrial samples are used to estimate the Hg isotope composition of the silicate Earth. The eucrites exhibit negative MIF (mass independently fractionated) for the odd-numbered Hg isotopes (199Hg and 201Hg). For the same odd-numbered isotopes, carbonaceous chondrites have positive MIF, ordinary chondrites have no MIF, and enstatite chondrites have positive MIF. Critically, the terrestrial igneous rocks have MIF and mass dependently fractionated isotopes that fall in the range defined by chondrites.