Results 121 to 130 of about 824 (171)
Some of the next articles are maybe not open access.
Geochimica et Cosmochimica Acta, 1988
C3 xenoliths in a C2 host (Murchison) are unique among known meteoritic xenolith-host occurrences. They offer an opportunity to determine possible effects on the xenoliths by the hydrated host. Eleven xenoliths were found ranging from 2 to 13 mm. Four of these Murchison Xenoliths (MX1, MX2, MX3 and MX4) have been studied in detail.
Olsen, Edward J. +5 more
openaire +2 more sources
C3 xenoliths in a C2 host (Murchison) are unique among known meteoritic xenolith-host occurrences. They offer an opportunity to determine possible effects on the xenoliths by the hydrated host. Eleven xenoliths were found ranging from 2 to 13 mm. Four of these Murchison Xenoliths (MX1, MX2, MX3 and MX4) have been studied in detail.
Olsen, Edward J. +5 more
openaire +2 more sources
The transport of xenoliths in magmas
Earth and Planetary Science Letters, 1977Abstract Field measurements of the rheology of Hawaiian and Etnean lavas have shown that, on eruption, they behave as Bingham liquids with yield strengths in the range 70–450 N/m 2 . Ultramafic nodules entrained in a Bingham liquid cannot settle unless the stress they impose on the liquid exceeds approximately 5–7 times its yield strength ...
R.S.J. Sparks +2 more
openaire +1 more source
The dynamics of xenolith assimilation
Contributions to Mineralogy and Petrology, 1998Xenolith assimilation has been simulated with experiments involving melting wax spheres into hot water and aqueous solutions and characterised by a theoretical analysis. Both the cases of neutrally buoyant stationary spheres and spheres sinking through the hot host fluid are examined. Melt generated on a sphere's surface flows (compositional convection)
Mcleod, P, Sparks, RSJ
openaire +1 more source
MANTLE XENOLITHS IN THE MATSOKU KIMBERLITE PIPE
Physics and Chemistry of the Earth, 1975Abstract The chemical compositions of selected xenoliths from the Matsoku pipe and many constituent minerals are discussed. It is concluded that the xenoliths form a closely related suite of rocks of differing mineralogy and chemistry which could have been produced during a single igneous event in the mantle. It is likely that at solidus temperatures
J.J. Gurney, B. Harte, K.G. Cox
openaire +1 more source
1980
Within kimberlite intrusions there are included fragments of a wide variety of rock types. Minerals derived from their fragmentation are incorporated into the host kimberlite, thereby giving it an extremely complex and hybrid mineralogy.
openaire +1 more source
Within kimberlite intrusions there are included fragments of a wide variety of rock types. Minerals derived from their fragmentation are incorporated into the host kimberlite, thereby giving it an extremely complex and hybrid mineralogy.
openaire +1 more source
Potassium and rubidium in ultramafic xenoliths
Geochimica et Cosmochimica Acta, 1970Abstract K and Rb contents of 13 ultramafic xenoliths and 6 specimens of associated basalt are presented. K Rb ratios of the xenoliths vary from about 60 to 600, while those of the hostbasalts lie in the narrower range of 200–340. Variation in the xenoliths may reflect mantle heterogeneity.
D.K. Paul, R. Hutchison
openaire +1 more source
Fluid inclusions in mantle xenoliths
Lithos, 2001Abstract Fluid inclusions in olivine and pyroxene in mantle-derived ultramafic xenoliths in volcanic rocks contain abundant CO2-rich fluid inclusions, as well as inclusions of silicate glass, solidified metal sulphide melt and carbonates. Such inclusions represent accidentally trapped samples of fluid- and melt phases present in the upper mantle, and
Tom Andersen, Else-Ragnhild Neumann
openaire +1 more source
Southern African Kimberlites and their Xenoliths
1991South African diamonds were found in primary kimberlite source rock in the late 1860’s and early 1870’s when Jagersfontein, Bultfontein, DeBeers, Dutoitspan, and other pipes near Kimberley (Fig. 1) were discovered in rapid succession (Wilson 1982; Janse 1984). Prior to this, stream gravels were the only diamond source worldwide.
J. J. Gurney +5 more
openaire +1 more source
XENOLITHS AT THRELKELD, CUMBERLAND
Proceedings of the Yorkshire Geological Society, 1940In the years 1925–6 I did a good deal of field-work on the so-called microgranite of Threlkeld and St. John’s Vale, with the intention of making a complete petrographic investigation of these rock masses. Material was collected and a number of microscope slices were cut.
openaire +1 more source
Diamondiferous eclogite xenoliths in kimberlite
Lithos, 1970Abstract The physical properties of garnet in diamond-kyanite-eclogite and diamond-corundum-eclogite are presented for the first time, and are compared with garnet in six newly available diamond eclogites. Garnets from diamond-bearing eclogites do not constitute a separate subdivision, but plot in the compositional fields appropriate to their ...
P.C Rickwood, Morna Mathias
openaire +1 more source