Analytical method: UNKNOWN
| Technique | UNKNOWN |
|---|---|
| Material | WHOLE ROCK |
| Mineral | none |
| Institution | Unknown, Unknown, USA |
| Reference | McGee, J J; Tilling, R I; Duffield, W A (1987) Petrologic characteristics of the 1982 and pre-1982 eruptive products of El Chichon Volcano, Chiapas, Mexico. Geofisica Internacional. 26; 1, Pages 85-108. 1987. |