MICROSPHERULES IN SNOW AND ICE-FOG CRYSTALS

• Main Author: Kumai, Motoi
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
• Format: Text
• Language: English
• Published: 1969
• Subjects: Meteorology; Snow; Ice and Permafrost; *ICE FOG; *SNOW; CLAY MINERALS; COAL; ELECTRON DIFFRACTION; ELECTRON MICROSCOPY; METEORITES; MICROSTRUCTURE; NUCLEATION; PARTICLES; SAMPLING; WASTE GASES; Fairbanks; Greenland; Ice; permafrost; Alaska
• Online Access: http://www.dtic.mil/docs/citations/AD0691326; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0691326

Spherules found in snow crystals, ice-fog crystals, fallout particles, and fly ash were studied with an electron microscope using the electron diffraction method. The central part of the residues of 1004 specimens of natural snow crystals from Greenland, the United States, and Japan were examined; 14 sperules 0.1 to 1.5 micrometers in radius were found among them. The residues of 658 artificial ice-fog crystals formed from water vapor in flue gases of coal-burning electric power plants at Fairbanks, Alaska, were also examined; nine spherules were found. Spherules similar to those found in ice- fog residues were found in furnace-produced fly ash fallout at Fairbanks, Alaska. The electron microscope study indicated that less than 0.7% of the 1004 snow crystals contained spherules of possible extraterrestrial origin, and that snow crystals are formed mainly on clay mineral particles by heterogeneous nucleation.