Physical and chemical characteristics of Mt. St. Helens airborne debris

Conference · Tue Jan 01 04:00:00 EST 1980

OSTI ID:7048196

Sedlacek, W A; Heiken, G H; Mroz, E J; Gladney, E S; Perrin, D R; Leifer, R; Fisenne, I; Hinchliffe, L; Chuan, R L

Tephra and aerosols from the May 18, 1980 eruption of Mt. St. Helens, Washington were sampled in the lower stratosphere with a WB-57F aircraft. The main body of the plume was intercepted over western Kansas on May 20, 48 hours after the eruption, at an altitude of 15.2 km. Concentrations on filter samples were 26 ng of SO/sub 4//g of air and 579 ng of ash/g of air. Angular glass pyroclasts ranged in size from 0.5 to 10 ..mu..m, with a mean grain size of 2 ..mu..m. Samples collected at altitudes of 16.7 and 12.5 km had only traces of SO/sub 4/ and ash. A second flight was flown, 72 hours after the eruption, on May 21. From north Texas to central Wyoming, at an altitude of 15.2 km, < 0.5 to 38 ng of ash/g of air and 1.0 to 2.2 ng of SO/sub 4//g of air were sampled. At an altitude of 18.3 km, from central Wyoming to NW New Mexico, the plume density and character were variable. Glassy pyroclasts similar to those sampled on the first flight range in size from 0.5 to 4 ..mu..m dia. Trace element analysis revealed some volatile element enrichment, but far less than previously observed in the plume from St. Augustine Volcano, 1976. Values of /sup 210/Po//sup 210/Pb were 0.7 to 1.32 comparable to the secular equilibrium value of 1.0 and far less than ratios previously reported by Lambert.

• Research Organization: Los Alamos Scientific Lab., NM (USA); Department of Energy, New York (USA). Environmental Measurements Lab.
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7048196
• Report Number(s): LA-UR-81-110; CONF-801160-2
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOL MONITORING
AEROSOLS
ALPHA DECAY RADIOISOTOPES
ASHES
ATMOSPHERIC CHEMISTRY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHEMISTRY
COLLOIDS
DATA
DAYS LIVING RADIOISOTOPES
DISPERSIONS
DISTRIBUTION
EARTH ATMOSPHERE
ECOLOGICAL CONCENTRATION
ELEMENTS
ERUPTION
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
HEAVY NUCLEI
INFORMATION
ISOTOPE RATIO
ISOTOPES
LEAD 210
LEAD ISOTOPES
MONITORING
NORTH AMERICA
NUCLEI
NUMERICAL DATA
OXYGEN COMPOUNDS
PACIFIC NORTHWEST REGION
PLUMES
POLONIUM 210
POLONIUM ISOTOPES
RADIOISOTOPES
RESIDUES
SOLS
SPATIAL DISTRIBUTION
STRATOSPHERE
SULFATES
SULFUR COMPOUNDS
TRACE AMOUNTS
USA
VOLCANOES
WASHINGTON
YEARS LIVING RADIOISOTOPES