Multi-element analysis of single dust grains in the μg-mass range

For the investigation of potentially extraterrestrial dust particles from polar ice and deep sea sediments LAMMA, EDAX, and INAA were applied to individual grains with the aim of a rapid chemical classification. By hand-picking under an optical microscope approximately 550 spherical objects in the range of 10-300 μm in diameter were extracted from the water-insoluble residue of ∝4 tons of shelf ice recovered at Atka Bay, Antarctica, near the German Georg-von-Neumayer Station. The deep sea spherules (DSS) originated from ∝400 kg of Pacific clay. Such microspheres are known to be candidates of having cosmic origin. (orig.)