Ejecta structure for the 1B-M20 model. The solid black line shows the enclosed ejecta mass (for a given velocity). The dashed colored lines show which velocities make the largest contribution to the mass of a given element; namely, the quantity 4πr³ρ_i, where ρ_i is the mass density of the i-th element, color-coded as in the legend. The solid colored lines show the mass density of the i-th element relative to the mass density of oxygen, normalized by the solar value.