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Tectonics of some amazonian greenstone belts
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Gibbs, A. K. |
| Copyright Year | 1986 |
| Description | Greenstone belts exposed amid gneisses, granitoid rocks, and less abundant granulites along the northern and eastern margins of the Amazonian Craton yield Trans-Amazonican metamorphic ages of 2.0-2.1 Ga. Early proterozoic belts in the northern region probably originated as ensimatic island arc complexes. The Archean Carajas belt in the southeastern craton probably formed in an extensional basin on older continental basement. That basement contains older Archean belts with pillow basalts and komatiites. Belts of ultramafic rocks warrant investigatijon as possible ophiolites. A discussion follows. |
| File Size | 277186 |
| Page Count | 3 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19860013633 |
| Archival Resource Key | ark:/13960/t88h3h94z |
| Language | English |
| Publisher Date | 1986-01-01 |
| Access Restriction | Open |
| Subject Keyword | Geophysics Amazon Region South America Geochronology Structural Properties Geology Island Arcs Cratons Lithosphere Iron Magnesium Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
