MICROSTRUCTURE OF EXPERIMENTALLY OXIDIZED OLIVINE FROM A MANTLE NODULE. I. MODES OF FE3+ AND OH- OCCURRENCE
- DSpace Home
- →
- Геология России
- →
- ELibrary
- →
- View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.
dc.contributor.author | Khisina N.R. | |
dc.contributor.author | Wirth R. | |
dc.contributor.author | Langer K. | |
dc.contributor.author | Andnit M. | |
dc.contributor.author | Ukhanov A.V. | |
dc.date.accessioned | 2021-04-10T07:00:45Z | |
dc.date.available | 2021-04-10T07:00:45Z | |
dc.date.issued | 2001 | |
dc.identifier | https://www.elibrary.ru/item.asp?id=36230543 | |
dc.identifier.citation | Geohimiya, 2001, 39, 4, 372-381 | |
dc.identifier.issn | 0016-7525 | |
dc.identifier.uri | https://repository.geologyscience.ru/handle/123456789/27615 | |
dc.description.abstract | Olivine (Fa 8.2%) from a mantle nodule in kimberlite (Udachnaya pipe, Yakutia) was heated in air at 700°C for 9 h and then examined by optical spectroscopy (IR and UV spectroscopy), electron microprobe analysis (EMPA), and transmission electron microscopy (TEM) using the method of electron energy-loss spectroscopy (EELS). Ultraviolet spectra recorded along the [001] plane showed the inward decrease of Fe3+. Three zones can be distinguished: (1) an oxidized rim containing Fe3+ as Fe3+-bearing phases and point defects within the olivine matrix; (2) a zone containing on by point Fe3+-bearing defects; and (3) an unoxidized core. Hydroxyl OH-absorption bands in the IR spectrum are typical of mantle olivine and are normally assigned to point OH-defects. However, the TEM-EELS study of the oxidized rim (with an electron beam diameter of 4 nm) established that OH- does not occur as point defects, but interacts with Fe3+ to form iron hydroxides (feroxyhyte, FeOOH, and bernalite, Fe(OH)3), which compose polyphase inclusions several hundred nanometers in size. Our investigations showed that IR spectroscopy combined with a TEM study is required to determine the modes of OH- occurrence in olivines and to correct the interpretation of OH- absorption bands in the IR spectra. Our data also indicate that hydroxyl-bearing olivine is principally oxidized differently to anhydrous olivine. In this case, instead of the typical oxidation products (laihunite, magnetite, hematite), Fe3+ and OH- defects interact to form iron hydroxides. | |
dc.title | MICROSTRUCTURE OF EXPERIMENTALLY OXIDIZED OLIVINE FROM A MANTLE NODULE. I. MODES OF FE3+ AND OH- OCCURRENCE | |
dc.type | Статья |
Files in this item
Files | Size | Format | View |
---|---|---|---|
There are no files associated with this item. |
This item appears in the following Collection(s)
-
ELibrary
Метаданные публикаций с сайта https://www.elibrary.ru