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Hinyang province (3)
Hinyang province (2)
Hinyang province (1)
5
6
10 000.0
10 0 0 0 .0
4
1
3
10 0 0 0 .0
1
1000 .0
1000 .0
10 0 0 .0
4
2
100 .0
2
100 .0
1
100 .0
3
3
10.0
Vitim province (2)
Vitim province (1)
10 .0
Vitim province (3)
10.0
2
1.0
C1
1.0
C1
1.0
C1
1 - Vt-16.1.1
(2 77 Ma)
1 - Vt-19.2.1
(1694 M a)
1 - Vt-19.3.1
(178 Ma )
0.1
0 .1
2 - Vt-16.9.1
(2 77 Ma)
0.1
2 - Vt-16.11. 1
(1506 M a)
2 - Vt-19.2.2
(174 Ma )
3 - Vt-16.3.1
(2 75 Ma)
3 - Vt-16.3.1
(1088 M a)
3 - Vt-16.1.1
(167 Ma )
4 - Vt-16.5.1
(2 64 Ma)
0.0
0
.0
0.0
La
Ce
Pr
Nd
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
La
Ce
Pr
Nd
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
La
Ce
Pr
Nd
Sm
Gd
Dy
Ho
Er
Tm
Yb
Lu
Eu
Tb
7
100 00 .0
Vitim province (4)
1000 .0
3
100 .0
10 .0
1
1.0
C1
1 - Vt-16.7.1
(165 Ma )
0.1
2 - Vt-19.4.1
(141 Ma )
2
3 - Vt-16.2.2
(139 Ma )
0.0
La
Sm
Gd
Dy
Ce
Pr
Nd
Ho
Er
Tm
Yb
Lu
Eu
Tb
Figure 4.5
1-3 - chondrite-normalized REE patterns and multielemental patterns for zircons from
peridotites in xenoliths from Hinyang alkaline basalt province (North China): 1 - zircons in
which LREE concentrations were not changed by epigenetic processes; 2 - zircons in which
LREE concentrations were changed by epigenetic processes; 3 - multielemental patterns
for zircons. 4-7 - chondrite-normalized REE patterns for zircons from peridotite in xeno-
liths from Vitim alkaline basalt province (Transbaykalia, Russia) with different isotopic age:
4 - 1088-1694 Ma; 5 - 264-277 Ma; 6 - 167-178 Ma; 7 - 139-165 Ma (data Table 4.4).
in some zircons, as well as the appearance of a brownish color, which indicates their
relative enrichment with LREE.
Gabbros, diorites, pyroxenites.
The REE composition of zircons from these rocks
is studied by the example of samples of pegmatite gabbros forming Khayalygsky mas-
sif (South-Western Tuva, Russia) [Oydup
et al
., 2006; Lesnov
et al
., 2007]. These zir-
cons are represented by idiomorphic short-columnar crystals of 0.2-1 mm in size and
of a color from pink to colorless. According to the results of U-Pb isotopic dating the
age of these zircons is 447.4
1.3 million years (Late Ordovician). Using the micro-
probe technique it was determined that the content of ZrO
2
in them is 66.4-66.9
wt%, HfO
2
- 0.85-0.99 wt%. The value of ZrO
2
/HfO
2
vary in the range of 67-78.
The total REE content varies in the range of 128-156 ppm, the values of (La/Yb)
n
in the range of 0.004-0.012 (Table 4.5). On the REE patterns of the studied zircons
there are relatively weak in intensity positive Ce anomalies and negative Eu anoma-
lies. At the same time, their multielemental patterns show intense positive anomalies
±
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