Investor Presentaiton
a
Features of chromitites
10
6
в
Chromite in the mantle peridotites of the massif. a) thin-banded, b) massive veins, c) schlieren.
100
Fe/Fe (Crsp)
II
10
Cr# (Crsp)
1.0
Chromites Ulan-Sardag massive
Grl Grll Grill
Literature data from different
★
geodynamic setting
0,8
* 4 * 5 *
6
* 7
8
*
9
10
A 11 A 12
* 13
A 14 A 15
0.6
*
0.4
0.2
Boninites
Alaskan
type
10
TiO2 ms% (Crsp)
LIP
***
OIB
IAT
Bon
0.1
ARC
*
*
MORB
Features of MPG mineralization in chromitites
☆
a
C
Os-Ir
Os
Lr
Ru-Ir-Os
b
Chr
10 μm
Cct
Mlr
RuAsS
Lr
(Ru,Os)S
10 μm
d
Lr
Er
Mg# (Crsp)
0.0
0.01
Al,O, ms% (Crsp).
1,0
0.8
0,6
0.4
0.2
0.0
0,1
0
5
10
15
20
25
30
35
40
45
50
MORB ES; Al# (21-60), Cr# (36-74), Mg# (59-84)
Boninite ES; Al# (14-23), Cr# (74-81), Mg# (46-63)
Literature data
10
20
Al2O3 ms% (Crsp)
30
40
50
Discriminatory diagrams showing the Al2O3 - Fe²+/ Fe³+, TiO2 - Al2O3
ratios and Cr-Mg# in the chromites of their chromites according to
literature data and data Ulan-Sar'dag massive.
Chemical parameters of chrom-spinelides and parental melt
Alyskyn type ES; Al#13-20), Cr# (67-81), Mg# (42-50) composition in equilibrium with podiform chromitites are
located in three fields: MORB, suprasubduction zones,
boninites, Alaskan type.
MORB from Mid oceanic ridge basalt; Cr#<0,7
Back-arc basalt; Cr#<0,7
Oceanic-island basalt; Cr<0,7
Island arc, high K and calc-alcalain basalt; Cr#>0,7
Iisland arc boninite and tholeite basalt; Cr>0,7
Large igneous province: Flood Basalt; Cr#>0,7
Spinel in abissal peridotites
Chromite in ophiolitic mantle high Al#
Chromite in ophiolitic mantle high Cr#
Chromitite in subcontinental mantle
Chromitite in continental layered intrusion
Chromitite in Alaskan-type complexes
20 μm
10 μm
Minerals of the platinum group in chromites (BSE): a) grain of iridosmin
in chrom- spinelide; b) concretion of millerite and zonal grain of laurite
(in the center of the phase with erlichmanite minal and inclusions of
osmium; c) concretion of laurite and laurit-erlichmanite with multiple
inclusions (Os-Ir-Ru); d) interpenetrating concretion of laurite and
erlichmanite with nanosized inclusions Os.
Distribution and PGE mineralization are typical for podiform chromitites of world ophiolite complexes. Platinum group
mineralization consist of Os-Ir solid solution, two generation of sulfides PGE (magmatic Lr-Er and hydrothermal newly-formed
Lr). Native osmium, ruthenium, RhNiAs are in close assotiation with chlorite, serpentine, sulfides of nikel. Metamorphism from
green shale to amphibolite facies leads to a change in magmatic platinum group minerals, dissolution, remobilization PGE. The
rise in temperature leads to the enlargement and agglomeration of nanoparticles of PGE from nano- to micro-level.View entire presentation