Abstract :
Looking at the supply side of mesospheric metals using compositions of surviving meteoroids, the average element abundances are not uniformly chondritic with Fe, S, Na and K depletions. The calculated mesospheric C/Si ratio is due to micrometeorites. The volatile element, e.g., C and Na, supplies show intra-annual variations. Yet, it may not affect their annual average abundances or correlate with observed seasonable variations in the mesospheric alkali element abundances. Condensed meteoric dust is scarce, except perhaps for nanometer size Fe-oxides or Fe-oxyhydroxide.
