Iron-rich microstructure records of high temperature multi-component silicate melt behavior in nuclear fallout

Above-ground nuclear explosions that interact with the surface of earth entrain materials from surrounding environment, influencing resulting physical and chemical evolution fireball, which can affect final phase mobility hazardous radionuclides are dispersed in environment as fallout particles. The interaction iron a explosion is specific interest due to potential for act redox buffer because likelihood significant masses metals be present urban environments. We investigated historic interacting conducted on steel tower report discovery widespread diverse iron-rich micro-structures preserved within samples, including crystalline dendrites micron-scale spheres liquid immiscibility textures. assert these reflect local conditions cooling rates inform interpretation high temperature events, enabling new insights into fireball condensation physics chemistry when (i.e. structural steel) vaporized or entrained. These observations also significantly expand availability silicate datasets applicable rapidly quenched systems such meteorite impact melt glass.