geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Metamorphic formation of Sr-apatite and Sr-bearing monazite in a high-pressure rock from the Bohemian Massif


, : Metamorphic formation of Sr-apatite and Sr-bearing monazite in a high-pressure rock from the Bohemian Massif. American Mineralogist 89(8-9): 1323-1329

Accessory, 10-300 mu m grains of Sr-apatites with SrO contents up to 33 wt% were found in a high pressure (26+ or -3 kbar, 830+ or -30 degrees C), garnet-rich rock from the Bohemian Massif, Czech Republic. Furthermore, this rock contains unusual, Sr-bearing, accessory monazite (SrO up to 2 wt%). It is argued that the Sr-apatite and the Sr-bearing monazite formed as a result of plagioclase breakdown during HP metamorphism. During a subsequent phase of near-isothermal decompression and partial retrogression of the HP paragenesis at 8+ or -2 kbar and 800-900 degrees C, many apatites have lost their Sr through diffusion to newly formed plagioclase, some of which accommodated SrO contents of ca. 7 wt%. At apatite/plagioclase contacts, a distribution coefficient C (super pl) (sub Sr) /C (super Ap) (sub Sr) of ca. 4 was measured, implying that in plagioclase-bearing rocks (i.e., most crustal rocks), Sr-apatites have little chance to form. In the investigated rock, only apatities enclosed and shielded in unretrogressed garnet were able to preserve high Sr. Despite strong compositional differences from grain to grain, individual apatites are homogenous with respect to contents of Sr, as well as REE and Y, showing that at ca. 800 degrees C, rapid diffusion must have taken place. In contrast to the apatites, monazite grains inside and outside of garnet were both equally Sr-bearing, lacking any signs of a secondary, diffusion-related Sr depletion, even in the most marginal zones. This observation, in conjunction with an occasionally preserved growth zoning, illustrates the status of monazite as a slow-diffusion mineral. Therefore, Sr-bearing monazite potentially may be an important long-term indicator of a HP history of rock units or terranes.

US$19.90

DOI: 10.2138/am-2004-8-921


Other references

Jackson, J.D.; Yan, Y.; Brunda, M.J.; Kelsey, L.S.; Talmadge, J.E., 1995: Interleukin-12 enhances peripheral hematopoiesis in vivo. Interleukin 12 (IL-12) is a cytokine that supports the proliferation and activation of cytotoxic T lymphocytes and natural killer (NK) cells. Recent evidence has suggested that IL-12 also has hematopoietic activities in vitro. We report studies th...

Ralph, W.M.; Liu, K.; Auborn, K.J., 2005: CCAAT/enhancer-binding protein beta represses human papillomavirus 11 upstream regulatory region expression through a promoter-proximal YY1-binding site. CCAAT/enhancer-binding protein beta (C/EBPbeta) can function as a repressor or as an activator of human papillomavirus (HPV) gene expression, depending on which cell type the experiments are conducted. In this report, it was shown that within prim...

Prekoppova, J.; Slottova, A., 1982: Determination of the number of yeasts and moulds in the ewes' milk cheese. Of 5 media tested, oxytetracycline-yeast extract-glucose agar gave highest counts of yeast and moulds after 4 days at 25 deg C. Wort agar and Sabouraud agar (pH 5) gave similar counts of Geotrichum spp.

Bendire, C., 1877: Notes on some of the Birds found in South-eastern Oregon, particularly in the vicinity of Cape Harney from November, 1874, to January, 1877. Proceedings of the Boston Society, XIX 109-149

Cazier, N.; Checoury, X.; Haret, L-Daniel.; Boucaud, P., 2013: High-frequency self-induced oscillations in a silicon nanocavity. We show that self-induced oscillations at frequencies above GHz and with a high spectral purity can be obtained in a silicon photonic crystal nanocavity under optical pumping. This self-pulsing results from the interplay between the nonlinear resp...

Asano Kiyosi, 1939: Limestones of the South Sea islands under Japanese mandate. Subdivides Tertiary limestones of the South Sea islands under Japanese mandate into six groups on the basis of included Foraminifera.

Häring, M.; Winter, W.; von Benken, H., 1984: Distal radius fractures at a municipal clinic. Causes, treatment and results. Unfallheilkunde 87(8): 351-353

Moreno-Otero, R.; Murakawa, Y.; Kanof, M., E.; Civeira, M., P.; Jones, E.A.thony; James, S., P., 1994: Defective proliferation and regulatory function of CD+ T cells bearing Leu-8 homing receptor in primary biliary cirrhosis: Phorbol myristate acetate enhances T-cell function. The majority of circulating CD4+ T cells express the Leu-8 peripheral lymph node homing receptor, and these cells have previously been shown to have suppressor-inducer and suppressor function. In the present study, it was found that CD4+, Leu-8+ T...

Elias, D.; Lasser, P., 1985: Surgical technics for implantation of hepatic intra-arterial catheters for local chemotherapy. Experience with 42 cases. Based on the experience of 42 cases of surgical implantation of hepatic intra-arterial catheters (HIAC) for local chemotherapy, the techniques used are analyzed principally as a function of anatomical variations of the hepatic artery. A convention...

Pirson S.J., 1976: Track record in ME exploration. Oil and Gas Journal 74(38): 241-244, 246, 249