Dynamic evolution of major element chemistry in protoplanetary disks and its implications for Earth-enstatite chondrite connection

Chondrites are the likely building blocks of Earth, and identifying group chondrite that best represents Earth is a key to resolving state early Earth. The origin chondrites, however, remains controversial partly because their puzzling major element compositions, some exhibiting depletion in Al, Ca, Mg. Based on new thermochemical evolution model protoplanetary disks, we show planetesimals with patterns similar ordinary enstatite chondrites can originate at 1-2 AU just outside where evaporates. Around "evaporation front" enstatite, large inward flow refractory minerals, including forsterite, takes place high pebble concentration, loss those minerals result When evaporated solid grains re-condense onto pebbles, concentration pebbles further enhanced, potentially triggering streaming instability. Planetesimals composition thus be naturally created terrestrial region. preferential forsterite also creates an enhancement Mg/Si heavy Si isotopes inside potential source region for chondrites. which shows both features, may were born.