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An atlas of volcanic ash
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Heiken, G. |
| Copyright Year | 1974 |
| Description | Volcanic ash samples collected from a variety of recent eruptions were studied, using petrography, chemical analyses, and scanning electron microscopy to characterize each ash type and to relate ash morphology to magma composition and eruption type. The ashes are best placed into two broad genetic categories: magnetic and hydrovolcanic (phreatomagmatic). Ashes from magmatic eruptions are formed when expanding gases in the magma form a froth that loses its coherence as it approaches the ground surface. During hydrovolcanic eruptions, the magma is chilled on contact with ground or surface waters, resulting in violent steam eruptions. Within these two genetic categories, ashes from different magma types can be characterized. The pigeon hole classification used here is for convenience; there are eruptions which are driven by both phreatic and magmatic gases. |
| File Size | 14914597 |
| Page Count | 108 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19740017769 |
| Archival Resource Key | ark:/13960/t09w56z6c |
| Language | English |
| Publisher Date | 1974-01-01 |
| Access Restriction | Open |
| Subject Keyword | Geophysics Scanning Electron Microscopy Petrography Lava Morphology Surface Water Electron Microscopes Volcanoes Catalogs Publications Magma Ashes Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
