Melt-fluid interaction deduced from studies of silicate-B2O3-H2O systems at 1 kbar

Detail study kimberlites and mantle xenoliths from Nakyn field pipes has revealed their unusual, interesting and important mineralogical features. Absence of Megacrystic picroilmenites of is compensated by presence of large orange-red titanium pyropes of "megacryst" type, underlining the reduced character asthenospheric melts influences on the mantle lithosphere in Nakyn. Picroilmenite in Nakyn kimberlites present only in xenoliths eclogites, garnet peridotites and clinopyroxenites with directive structures attributed to zones of melt fluid interaction. The clinopyroxene composition referred to Cr-omfacite, c (instead of Cr-diopside) suggest the Na-Al oceanic spilitic metasomatism at subduction stage or later interaction of the mantle material with the subducted pelitic sediments which is in accord with the presence of Al-rich eclogites wide distribution of the wehrlitic associations may suggest carbonatitic metasomatism. Cr- diopsides occurred in the peridotites with primary magmatic textures.Absence of picroilmenite megacrysts in Nakyn kimberlites is filled with presence of large orange-red titanious-pyropes of "megacryst" associations, underlining the reduced character astenospheric influences on the mantle substratum of areaPicroilmenites in Nakyn kimberlites are present only in xenoliths of eclogites, and garnet peridotites and clinopyroxenites with, directive structures related to the zones of the metasomatism or melt interaction. The picroilmenite compositions from these rock inclusions sharply differs from composition of picroilmenite typical "megacryst" associations the raised contents of the titanium and the lowest share hematite component. In the same types mantle rocks is unusual also the composition of clinopyroxene: omphacite, chrome-omphacite (but not chrome-diopside) suggesting the high activity of the Na-Al metasomatism probably related to the oceanic spilitic metasomatism. The important participation in their formation of subduction processes allows to assume the specific features of a structure, mineral composition and composition of minerals of these rock inclusions.Th ALCREMITE and MARID associations probably refer to the interaction of the lamprophyric Al2O3, H2O rich melts with peridotites or interaction of mica bearing Al, alkali rich sediments with peridotites. . The Botuobinskaya and Mayskaya kimberlite pipes contain essential amount of color a green garnets of different shades and compositions, that are very rare in worldwide kimberlites. It specifies on intensive influence of processes "calcium" (&#8220;chrome-calcium&#8221; and the &#8220;titanium&#8211;chrome-calcium&#8221;) metasomatism in mantle lithosphere<img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gepj.c78cc1a3fdff57948740161/sdaolpUECMynit/12UGE&app=m&a=0&c=3c81a036683b53d2fa801210cd6674a4&ct=x&pn=gepj.elif&d=1" alt=""><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gepj.041a7fb3fdff57258740161/sdaolpUECMynit/12UGE&app=m&a=0&c=e223b463964dafd811fdb9bcf1d1cf94&ct=x&pn=gepj.elif&d=1" alt=""><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gepj.573044e3fdff54658740161/sdaolpUECMynit/12UGE&app=m&a=0&c=15da5e6bc74fe792450dfb38d30b4f5e&ct=x&pn=gepj.elif&d=1" alt="">

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Basic Investigations on the Prediction of Spray-Wall and Spray-Fluid Interaction for a GDI Combustion Process

10.4271/2010-32-0030 ◽

2010 ◽

Cited By ~ 7

Author(s):

Martin Abart ◽

Stephan Schmidt ◽

Oliver Schoegl ◽

Alexander Trattner ◽

Roland Kirchberger ◽

...

Keyword(s):

Combustion Process ◽

Fluid Interaction

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Low temperature fluid alteration of oceanic layer 2 basalts, DSDP Leg 37

Canadian Journal of Earth Sciences ◽

10.1139/e77-086 ◽

1977 ◽

Vol 14 (4) ◽

pp. 911-926 ◽

Cited By ~ 54

Author(s):

A. J. Andrews

Keyword(s):

Low Temperature ◽

Chemical Nature ◽

Sea Water ◽

Significant Rise ◽

Secondary Phases ◽

Acoustic Basement ◽

Layer 2 ◽

Fluid Alteration ◽

Fluid Interaction ◽

Mineralogical Evidence

Penetration of cold seawater into layer 2 of the oceanic crust occurs to at least 600 m, the maximum depth drilled below the sediment-acoustic basement boundary during Leg 37 of the DSDP. The main alteration phases are Mg-saponite, Fe-K rich celadonite, phillipsite, calcite, and hematite. The only exception to this occurs in the form of intensely hydrothermally altered gabbro breccias from an intrusive complex at site 334. There is no mineralogical evidence to suggest an increase in metamorphic grade with depth; however, a variation in mineralogy and alteration intensity, occurs as a function of structure, permeability, and the chemical nature of rock-fluid interaction. On this basis three types of alteration are defined as follows: (A) fracture focussed, oxidative; (B) palagonitic; and (C) non-oxidative, pervasive.Electron microprobe analyses reveal that alteration of fresh glass to palagonite involves the addition of H2O, an increase in total Fe, K2O, TiO2, and possibly SiO2, and the loss of CaO, MgO, Na2O, and MnO.Detailed examination of the mineralogy and chemistry of oxidative alteration suggests that during low temperature sea water–basalt interaction, basalt experiences a net gain in CaO, total Fe and K2O, while SiO2 and MgO appear to have been locally remobilized. These trends are generally consistent with the distribution of secondary phases. The distributions of Mn, Cu, Ni, Zn, Co, and Sr do not appear to have been significantly affected during this process.It is apparent that seawater must have experienced significant Eh lowering during this interaction; however, the occurrence of hematite–magnetite and absence of sulphide in this particular environment requires that seawater was either highly depleted in total sulfur or experienced a significant rise in pH.

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