The early Cretaceous anorogenic Erongo Granite of Namibia is known to host abundant boron mineralization in rounded, quartz-tourmaline clusters and in NYF-type miarolitic, pegmatitic cavities. Rock and mineral samples were taken from the bulk granite, tourmaline nests, and miarolitic cavities and analyzed using a variety of modern analytical techniques. Geochemical and mineralogical data suggest substantial input from the metasedimentary rocks of the Damara orogen was important in the genesis of the Erongo Granite magma. The geochemical signature of the Damara orogen is most evident in the tourmaline clusters and miarolitic cavities, where fractional crystallization accumulated volatile and incompatible elements enough to exsolve a second fluid phase and induce drastic textural and mineralogical changes. As a result, the geochemical character of the pegmatitic cavities is far removed from that of classic NYF-type systems, where boron mineralization is usually not observed.
| Identifer | oai:union.ndltd.org:uno.edu/oai:scholarworks.uno.edu:td-2864 |
| Date | 16 May 2014 |
| Creators | Boudreaux, Andrew P |
| Publisher | ScholarWorks@UNO |
| Source Sets | University of New Orleans |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | University of New Orleans Theses and Dissertations |
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