MINERALOGY OF MANTLE XENOLITHS FROM THE PLIOCENE BASANITES OF THE DZHILINDA RIVER (VITIM VOLCANIC FIELD)
- 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 | Litasov K.D. | |
dc.contributor.author | Litasov Yu.D. | |
dc.contributor.author | Mekhonoshin A.S. | |
dc.contributor.author | Malkovets V.G. | |
dc.date.accessioned | 2021-02-01T11:15:26Z | |
dc.date.available | 2021-02-01T11:15:26Z | |
dc.date.issued | 2000 | |
dc.identifier | https://elibrary.ru/item.asp?id=29270228 | |
dc.identifier.citation | Russian Geology and Geophysics, 2000, 41, 11, 1534-1556 | |
dc.identifier.issn | 1068-7971 | |
dc.identifier.uri | https://repository.geologyscience.ru/handle/123456789/24315 | |
dc.description.abstract | Abundant mantle xenoliths found in Pliocene basanites from the Dzhilinda River are divided into three groups. These are: (1) coarse-grained protogranular spinel and garnet spinel Iherzolites (two-pyroxene temperature T = 1100-1250 degreesC; orthopyroxene-garnet pressure P = 18-23 kbar); (2) spinel Iherzolites and harzburgites of protogranular (2a) to tabular equigranular (2b) microstructures (T = 800-900 degreesC; P = 10-15 kbar); (3) mosaic equigranular Iherzolites (T = 710-750 degreesC). Peridotites of groups 1 and 2a are primitive or slightly depleted mantle substrata of two depth levels corresponding to garnet-spinel transitional layer and spinel stability field. The 2b peridotites and related low-Al websterites result from low-temperature depleted mantle-basaltic melt interaction under oxidizing conditions (close to QFM buffer). Peridotites of group 3 are enriched in modal pyroxene and spinel. They characterize a unigue type of mantle-melt interaction resulting from percolation of Ti-Zn-bearing melt through extremely depleted peridotites. Minerals of these peridotites have a specific chemical composition. Clinopyroxenes contain 2-2.2% TiO(2), olivines 0.7% NiO, and spinel 0.6-0.7% NiO and 0.9-1.0% ZnO. Cr-diopside pyroxenites and peridotites from the Dzhilinda are subdivided into two groups: high-temperature (T = 1000-1230 degreesC) and low-temperature (T = 860-1000 degreesC). They are considered the products of interaction between basaltic melts and primitive peridotites at two depth levels - 60-80 and about 50 km. Al-augite pyroxenites are represented by spinel websterite and are compositionally similar to low-temperature Cr-diopside pyroxenites. The Al-augite pyroxenites make up the uppermost mantle or lower crust at a depth of 35-50 km. Clinopyroxene megacrysts are rich in Mg and are similar to Mg-rich garnet pyroxenites from Miocene picrite-basalts, Pressure estimates suggest that they form at a depth of 60-80 km. The skarn-like clinopyroxenites, most likely, form from volatile-rich low-Al melts in the middle-lower crust. The estimations based on fluid inclusions show that pressures were no lower than 5-6 kbar. | |
dc.subject | Pliocene | en |
dc.title | MINERALOGY OF MANTLE XENOLITHS FROM THE PLIOCENE BASANITES OF THE DZHILINDA RIVER (VITIM VOLCANIC FIELD) | |
dc.type | Статья | |
dc.subject.age | Cenozoic::Neogene::Pliocene | en |
dc.subject.age | Кайнозой::Неоген::Плиоцен | ru |
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