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Geochemistry of metabasites and gabbroic rocks from the Tepla-Domazlice zone.

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Abstract and Figures

Various amphibolites, metagabbros and eclogitic relics of the Mariimske Lazne complex, and amphibolites from the Cerna Hora Massif exhibit an uniform geochemical character which compares well with modern mid-ocean ridge basalts. Geochemically these metabasites are similar to the amphibolites of the My to area and to schistose. partly striped amphibolites of the neighbouring Tirschenreuth-Mahring Zone and the Erbendorf-Vohenstrauss Zone (Bavaria). Greenschists and amphibolites from the Domailice metamorphic complex show an alkaline-basaltic tendency conforming to modern within-plate basalts or basalts from anomalous midocean ridge segments. In their chemical character, these metabasites compare well with the flaseramphibolites of the Erbendorf-Vohenstrauss Zone. Fine-grained amphibolites in the Warzenrieth area and gabbroic amphiboltes in the Blatterberg-Hoher Bogen area show normal MORB character. The metamorphosed gabbroic rocks in the southern part of the Neukirchen-Kdyne (meta-) igneous complex are subalkaline-tholeiitic and exhibit a magmatic differentiation trend. They differ from the neighbouring amphibolites by generally lower contents of incompatible elements.
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GEOCHEMISTRY
OF
MET ABASITES
AND GABBROIC ROCKS
FROM THE
TEPlA-
DOMAZlICE
ZONE
U_
Schiissler',
Z.
Vejnar',
M.
Okrusch"
S.
Rose'
and
E.
Seidel'
1 Mineralogisches Institut.
Universitat
Wurzburg,
Am
Hubland, 0-8700 Wurzburg,
F_
R.
G.
, Geological Survey, Prague, Czechoslovakia
,
Institut
fur
Angewandte
Mineralogie,
Universitat
Regensburg,
Kumpfmuhlerstrasse
2,
0-8400
Regensburg,
F.
R.
G.
4 Mineralogisch-Petrographisches Institu!,
Universitat
Kdln,
Zulpicher
Strasse 49,
0-5000
Kdln,
F.
R.
G.
Abstract
Various amphibcl:tes,
metagabbros
and eclogitic relics
of
the
Mariimske
Lazne
complex,
and
amphibolites
from
the
Cerna
Hora
Massif
exhibit
an
uniform
geochemical
character
which
compares
well
with
modern
mid-ocean
ridge basalts. Geo-
chemically
these metabasites are
similar
to
the
amphibolites
of
the
My
to
area and to schistose. partly
striped
amphibolites
of
the
neighbouring
Tirschenreuth-Mahring
Zone and
the
Erben-
dorf-Vohenstrauss
Zone (Bavaria).
Greenschists and
amphibolites
from
the
Domailice
metamor-
phic
complex
show
an alkaline-basaltic
tendency
conforming
to
modern
within-plate
basa!ts
or
basalts
from
anomalous
mid-
ocean ridge segments.
[n
their
chemical
character, these meta-
basites
compare
well
with
the
flaseramphibolites
of
the Erben-
dorf-Vohenstrauss
Zone. Fine-grained
amphibolites
in the
Warzenrieth area and (gabbro-i amphiboUtes in the Blatter-
berg-Hoher
Bogen area
show
normal
MORB character. The
metamorphosed
gabbroic
rocks in the
southern
part
of
the
Neukirchen-Kdyne
(meta-)
igneous
complex
are subalkaline
-
tholeiitic
and
exhibit
a
magmatic
differentiation
trend.
They
differ
from
the
neighbouring
amphibolites
by
generally
lower
contents
of
incompatible
elements.
Introduction
The pre-site studies
of
the
German
Continental Deep Drilling
Project KTB led
to
a
new
paleotectonic
concept
for
the
western
part
of
the
Bohemian Massif,
strongly
influenced
by
plate tec-
tonic
models.
The essential
point
of
the
new
concept
is a colli-
sion and
thrusting
of
the
Moldanubian
onto
parts
of
the
Saxo~
thuringian.
Subsequent
to
the collision
both
units
were
partly
overthrusted
by
a nap pe
complex,
relics
of
which
are
the
Mun·
chberg
nappe
pile,
the
Erbendorf-Vohenstrauss
Zone
with
the
Erbendorf
Greenschist Zone at its base and, possibly, the
Tepla-Domazlice
Zone (Weber and
Vollbrecht
1986).
Moldanu-
bian and Saxothuringian
were
welded
by
a last
low-pressure
metamorphism
330
to
320
Ma
ago. In
contrast,
the last
meta·
morphic
event
in the crystalline nappes
of
the
Munchberg
pile
and the
western
part
of
the
Erbendorf-Vohenstrauss
Zone is
of
medium-pressure
type and
took
place in
the
Early Devonian
around
380 Ma ago (e.g.
Blumel
1983, ScnDssler
et
aL
1986,
Teufe11988, Kreuzer
et
aL
1989). The
Erbendorf-Vohenstrauss
Zone and the
Erbendorf
Greenschist
Zone
partly
suffered
a ther-
mal
influence
by
the
late Hercynian
granite
intrusions
324 and
310 Ma ago (e.g. Kohler and
Muller-Sohnius
1976,
Wendt
et
aL
1986). The
most
conspicuous
metamorphic
event
in
the
Tepla-Domazlice
Zone
was
also
of
medium-pressure
type
(Vejnar 1972, 1977, Slumel 1983) and,
judging
from
extensive
K-Ar
dating,
took
place in Devonian times.
However,
a later
thermal
influence
around
320 Ma is
obvious
(Kreuzer
et
al. this
volume).
In all three units metabasites
form
important
constituents
which
provoke
a geochemical
comparison.
Our
joint
Czecho-
slovakian-German
working
group
started
new
geochemical
in-
vestigations
on
metabasites
and
gabbroic
rocks
of
the
Tepla-Domailice
Zone in
order
to enabie a
comparison
with
recent
geochemical data on the metabasites
from
the
other
two
allochthonous
units
(Schussler 1987,
Sch"ssler
et
aL
1989,
Okruscr.
et
al. in press}.
Furthermore,
the
geochetricai
charac-
teristics
of
the
various
amphibolite
complexes
in the T
epla-
Domailice
Zone and the
relationship
between
the
amphibolites
and the
gabbroic
rocks in the
Neukirchen-Kdyne
(meta-)
igneous
complex
will
be evaluated.
Geologv
and
sample
characteristics
Metabasites
of
the Marianske LilZne complex
Witnin
the
Bohemian
MaSSif the Mari,3nske Lazne
complex
represents one
of
the
largest
metabasite
accumulations
(Kastl
and Tonika 1984). It is
bordered
by
kyanite/sillimanite
bearing
paragneisses
of
the
Tepla
anticlinorium
in the
southeast
and
by
Variscan granite
intrusions
in
the
northwest.
The
dominating
metabasites are intercalated
by
serpentinites, paragneisses,
marbles, calcsilicate rocks and orthogneisses.
According
to
Kastl and Tonika (1984).
the
various
types
of
metabasites
exhibit
a zonal
distribution:
The
outer
flanks
of
the
complex
are
formed
by
garnet-free
amph~bolites
and
by
sphene~bearing
garnet
amphibolites,
whereas
rutiie-bearing
garnet
amphibolites,
eclogite
amphibolites
and eclogites are
concentrated
in the center. Kastl and Tonika (1984)
interpreted
this
arrangement
by
an increase
of
P-T
conditions
from
the
margins
to
the
core
of
the
complex
during
the (single-stage?)
metamorphism.
However,
judging
from
the
situation
In
the
Munchberg
complex
and
from
other
ec/agite
occurences
in
dif~
ferent
parts
of
the Variscides a
two-stage
metamorphism
should
be
considered:
Mineral
assemblages
c;>f
the
earlier high-
pressure
event
were
overprinted
by
a
medium-pressure,
am-
phibolite-facies
metamorphism.
This
view
is
corroborated
by
textural
evidence
observed
in
thin
sections
of
our
samples (see
below), The Marianske Lazne
complex
furthermore
contains
lenses
of
gabbros
and
gabbronorites
which,
according
to
Kastl
and Tonika
(19841.
were
"apparently
formed
at
the end
of
the
metamorphic
cycle".
Samples
ofthe
following
metabasite
types
were
investigated:
Schistose
amphibolites
(samples 69, 70) are
medium
to fine
grained. They contain greyiSh-green
hornblendes
of
an
older
generation
which
are
surrounded
by
younger
aggregates
of
smaller, lath-shaped
hornb[endes
of
the
same colour. Plagio-
clase is
partly
altered to serlcite
or
saussurite. Opaques are
overgrown
by
sphene. Samples 66 and
67
are
transitional
to
garnet·bearing
hornblende-gneisses
with
high
amounts
of
quartz and plagioclase.
Some
of
the schistose
amphibolites
(sample
58)
may
contain
intercalations rich in
biotite
which
is
partly
replaced
by
chlorite.
Garnet- and
rutile-bearing
flaserampnibolites
(sampies
59,
60,
61, 65, 68)
strongly
resemble the
flaseramphibolites
of
the
Erbendorf-Vohenstrauss
Zone in
their
textural appearance
and
mineralogy
(but
not
in
their
trace
element
chemistry,
see
belowl).
The
medium
grained rocks
consist
of
xenoblastic
piagioc)ase and greyish-green,
hypidioolastic
hornblende.
Gar-
247
net is
widely
replaced by finegrained aggregates of hornblende,
piagioclase and epidote. Rutile is the
predominant titanium
mi-
neral; other accessories are sphene, apatite and opaques. Later
alteration processes led
to
the
formation
of
sericite and
saussurite in piagioclase
as
well
as
to partial replacement
of
hornblende
by
chlorite and epidote and
of
ilmenite by leu-
coxene.
The eclogitic rocks
in
investigated (samples 62, 63,
64)
exhibit
relics of the high-pressure assemblage
garnet-omphacite-
rutile,
but
display
textural
evidence
for
strong
post-eclogitic
overprint. Part
of
the
garnet
and
most
of
the
omphacite
are
replaced
by
extremely
fine-grained,
symplectitic
aggregates
(plagioclase + ?pyroxene/hornblende). Their
formation
may
be
correlated
to
a
decompression
after
the
eciogite-facies
meta-
morphism.
A renewed
metamorphic
overprint
under
medium-
pressure, amphibolite-facies conditions is
documented
by
the
formation
of
coarser
olive-green
to
brown
hornblende
and
plagioclase
which
may
be
intimately
intergrown.
Sample
62
was
furtheron
affected
by a
latestage
retrogressive
alteration
with
formation
of
epidote, chlorite and sericite,
Metagabbros
(sample
57)
are characterized
by
relics
of
cli-
nopyroxene
which
are
overgrown
by
porphyroblasts
of
yellow
hornblende,
intensively
dusted
by
opaques. In
their
vicinity
flakes
of
reddish-brown biotite and larger opaque graines occur
Retrograde
influences
led
to
the
formation
of
pale-green
to
co-
lourless
?actinolitic
amphibole
and
to
sericitization
of
the
coarse-grained
plagioclase.
Amphibolites
in
Moldanubian
gneisses
near
My
to
west
of
Tachov
In
the
My
to
area several
small
bodies
of
amphibolite
are inter-
calated
within
the
Moldanubian
sillimanite
gneisses
west
of
the
Bohemian
Quartz Lode.
They
may
represent
a
continuation
of
the
amphibolites
in
the
Tirschenreuth-Miihring
Zone (Bavaria)
which
forms
a
transition
between
the
Moldanubian
and
the
Saxothuringian
realms. In
order
to
corroborate
this
assumption
by
geochemical constraints, samples
41
and
43
were
analyzed
from
the
occurrence
near
My
to. The
medium-
to
fine-grained
amphibolites
consist
of
pale olive-green to greyish-green
(Y,
Z)
hornblende (partly altered
to
chlorite),
of
plagioclase, subor-
dinate
biotite
and
accessory
sphene,
apatite
and
opaques. A
characteristic
of
the
My
to
amphibolites
is
the
high
amount
of
calcsilicate intercalations.
They
consist
of
clinopyroxene
and
sericitized plagioclase; some layers contain additional garnet
and
carbonate.
This
feature
is
at
variance
to
the
amphibolites
of
the
Tephi-Domailice
Zone,
but
also the
Tirschenreuth-Miihr-
ing Zone. In gneisses
associated
with
the
amphibolites
in the
M00
outcrop,
the
assemblage
biotite-microcline-sillimanite
-corundum-plagioclase
is recognized. This
assemblage
con-
forms
to
the temperatures
of
about
7500 C (at pressures
of
3 to
4.5 kbar) estimated by
Wagener-Lohse
and Blumel (1986) for
the
highest
grade
of
low-pressure
type
metamorphism
in the
Tirschenreuth-Mahring
Zone.
Amphibolites
of
the
Cerna
Hara
massif
near
Hostoun
The amphibolite bodies are intercalated
with
micaschists and
paragneisses
of
the
Tepla-Domazlice
Zone.
The
complex
is
intruded
by
later
Hercynian
granites
and,
at
its
western
border,
delineated
by
the Bohemian Quartz Lode.
Judging
from
the
isograd
pattern mapped by Veinar (1972) the grade
of
medium-
pressure
metamorphism
increases
from
east
to
west.
The
Cerna
Hora
metabasites
are
associated
with
metapelites
of
the
staurolite
and the kyanite zone.
The investigated
amphibolite
samples
(38,
46
to
55)
are
very
fine-
to
(rarely) medium-grained. Some
of
them
exhibit
a
well
developed
schistosity. A fine
banding,
caused
by
a
variation
in
24R
1 [[IT]
20
3~
4~
50
60
7[?;1
.
J,7
S
TANKOV
B
:;
10km
__
-------1-
_____
-.-l
1.
Geological
situation
in
the
southern
part
of
the
Tepla-Domai.lice
zone,
based
on
the
geological
maps
of Bavaria
1:
500 000
(8ayerisches
Geologisches
landesamt,
Munchen),
CSFR
1 : 25 000
(Geological
survey
Prague)
and
on
the
compilation
of
Troll
and
Weiss
(1988),
with
sample
localities.
1 -
metapelitic
rocks
of
the
Tepla-Domai.lice
zone;
2 -
metabasic
rocks; 3
-
gabbroic
and
dioritic
rocks
of
the
Neukirchen-Kdyne
(meta-
l
igneous
complex;
4 -
granites;
5 -
faults;
6 - FRG/CSFR
frontier;
7 -
sample
sites:
filled
squares
-
(gabbro-)
am-
phibolites
of
the
BUitterberg-Hoher
Bogen
area.
Open
squares
-
amphibolites
of
the
Warzenrieth
area.
Rhombs
-
greenschists
and
amphibolites
from
the
southeastern
part
of
the
Domazlice
metamorphic
complex.
Crosses
-
gabbroic
rocks
of
the
Neukirchen-Kdyne
(meta-j
igneous
complex.
Triangles
-
metapelitic
rocks
discussed
by
Kreuzer
et
al.,
this
volume.
MO
-
Moldanubien.
ZTT
-
Tepla-Domazlice
zone.
B -
Barrandian.
the
hornblende/plagioclase
ratio
or
by
intercalation
of
c1inopy-
roxene-rich
layers is
observed
in
some
of
the
samples.
Usually
the hornblendes are pale-green
to
pale-bluishgreen
(Z).
Poikil-
oblastic
garnet
may
be
present
as
additional
phase.
Retrograde
alteration
is
indicated
by
saussuritization
of
plagioclase and
by
infiltration
of
monomineralic
carbonate
veins.
Metabasites
of
the
Domazlice
metamorphic
complex
and
gabbroic
rocks
of
the
Neukirchen-Kdyne
(meta-)
igneous
complex
The
southern
part
of
the T
epla-Domai:ilce
Zone is
formed
by
a
metamorphic
complex
consisting
of
SW-NE
trending
meta-
basite bodies intercalated with metapelites. The grade
of
re-
gional
metamorphism
increases
from
NE
to
SW, as
indicated
by
a
succession
of
isograds
in the
metapelites:
biotite,
garnet,
staurolite and kyanite (Vejnar 1972). The transition from green-
schist
to
amphibolite
facies
occurs
between
the
biotite
and the
garnet
isograd.
,,~1
1
LLLJ
2C]
3t~
4GJ
5 [Z,j
10krT'
2.
Geological
situation
in
the
northern-
and
central
parts
of
the
T
epla-Domazlice
zone
based
on
the
geological
maps
of CSFR
1 : 200 000
and
1:
25 000
(Geological
Survey
Prague),
with
sample
localities.
Symbols
as
in fig. 1.
Sample
sites:
Filled
circles
-
metabasites
of
the
Marianske
lazne
complex
and
Cerna
Hora massif.
Open
circles
-
amphibolites
of
the
MYto
area.
Triangle -
diorite
of
the
Mutenin
stock.
The
Domazlice
metamorphic
complex
contains
several
large
intrusions
of
varying
composition,
the
Neukirchen-Kdyne
(meta·) igneous complex. It is
interpreted
by Vejnar (1986)
as
a
Skaergaard-type layered
intrusion
of
Late Cadomian ICambrian)
age
which
can be
subdivided
into
three
strati
form
units.
The
lower,
gabbroic
zone
forms
a
sequence
of
olivine
gabbros,
olivine
gabbronorites,
anorthosites
and
olivine
ferrodiorites.
In
the
middle
zone
two-pyroxene
diorites
predominate,
whereas
the
upper
zone
consists
of
quartz
diorites.
A
younger
intrusive
phase is
represented
by
tonalites,
trondhjemites
and
grano-
diorites.
Around
the
igneous
intrusions
the
crystalline
schists
of
the
Domazlice
metamorphic
complex
suffered
a
strong
thermal
overprint,
leading
to
a
contact
aureole
up
to
4 km
wide.
Moreover,
contact-metamorphosed
xenolites
of
the
country
rocks are
frequently
observed
in the
intrusives.
In
the northern part
of
the
Neukirchen-Kdyne
(meta-)
igneous complex, Veinar (1986) describes local
metamorphic
recrystallization,
mostly
accompanied
by
the
formation
of
secondary
amphiboles.
This
metamorphic
overprint
was
much
more
intensive
in the
southern
part
of
the
complex
where
all
transitions
between
gabbroic
relics and
fine-grained
am-
phibolites
can be
observed
(Fisc
her
1930
and
own
observations,
see beloW). The increase
of
metamorphic
recrystallization in the
gabbroic
rocks
from
NE
to
SW
fits
well
into
the
isograd
pattern
mapped
by Veinar (1972) in the
Domailice
metamorphic
com-
plex,
attributed
to the
medium-pressure
event
about
380 Ma
ago (Kreuzer et
al.
1989 and this volume). This could lead
to
the
assumption
that
the
metamorphic
overprint
of
the
gabbroic
rocks
took
place
during
this event. However, the thermal in-
fluence
of
the
igneous
intrusions
on the Domazlice
metamor-
phics
as
observed by Veinar (1986) contradicts this interpreta-
tion.
Further
detailed
investigations
are
necessary
to
solve
this
enigma.
Samples
of
the
following
rock
types
were
investigated:
The
greenschists
of
the
Domazlice
metamorphic
complex
Isample 17,
28)
are
very
fine-grained, often schistose and
sometimes
folded.
They
consists
of
pale-green
chlorite
(clino-
chlore), bluish-green
(Z)
amphibole, epidote, albite and sub-
ordinary
quartz.
Leucoxene
and
opaques
may
be
present
in
considerable
amounts.
Carbonate
is
either
dispersed
in the
rock
or
concentrated
in
layers
or
veins.
The
amphibolites
of
the
Domailice
metamorphic
complex
(20,29
to
34)
are
medium-
to fine-grained. They consist predo-
minantly
of
hornblende
and plagioclase and contain
frequently
biotite (partly chloritized),
sometimes
also thin layers rich in
epidote.
Accessory
minerals
are
opaques
and sphene. The
com-
plex
history
of
the rocks is
documented
in a
multiple
zonation
of
the amphiboles (for details see Veinar 1977).
In
some
of
the
investigated
samples,
a
retrograde
overprint
is
shown
by
a
de-
composition
of
hornblende
into
chlorite
and
epidote
and
by
a
sericitization
of
plagioclase.
Gabbroic relics
in
the southern part
of
the
Neukirchen-
Kdyne (meta-) igneous
complex
Isamples 8, 9; 324, 325, 329,
330,332,413-415,420-422)
are characterized by a
medium-
to
coarse-~rained,
granular
texture
formed
by
disorientated
tabular
plagioclases
and
xenomorphic
pyroxenes.
In
some
of
the
samples
large flakes
of
primary
biotite
can be
observed.
Accessories
are
large
grains
of
opaques
and
long
prisms
of
apatite.
In
all
gabbroic
rocks
investigated
a
metamorphic
over-
print
is
clearly
documented,
leading
to
different
degrees
of
am-
phibolilization. The pyroxenes are
partly
or
totally replaced
by
different
types
of
amphibole
which
OCcur
either
as
large
xenoblasts
dusted
by
opaques
or
as
fine-grained,
granoblastic
to
fibroblastic aggregates.
Judging
from
their
different
colours
the
amphiboles
must
be
highly
variable
in
composition.
In
one
of
the samples porphyroblasts of
yellow
hornblende are partly
replaced
by
tartan-like
aggregates
of
biotite.
During
the
meta-
morphic
overprint,
the
igneous
plagioclases
were
gradually
re-
crystallized
to
finer-grained,
granoblastic
aggregates.
Amphibolites
of
the Warzenrieth area are
medium-
to fine-
grained
and
exhibit
a
more
or
less
developed
schistosity.
Main
constituents
are
yellow,
rarely
olive·green
(Z)
hornblende,
plagioclase, and
sometimes
clinopyroxene;
sphene,
opaques,
zircon and
apatite
are
present
in
subordinate
amounts.
Epidote
occurs
as
an
alteration
product.
Judging
from
textural
evidence
at
least
some
of
the
fine-grained
amphibolites
can be
derived
from
gabbroic
rocks
of
the
Neukirchen-Kdyne
(meta-)
igneous
complex.
However,
some
of
the
amphibolites
bodies
in
the
Eschlkam-Warzenrieth
area
may
form
extensions
of
the
Domazlice
metamorphic
complex.
The (gabbro-)
amphibolites
of
the
Blatterberg-Hoher
Bogen
area
form
a
distinct
petrographic
group
which
is characterized
by a flaser texture
with
poorly
developed schistosity. The horn-
blende/plagioclase ratio is
extremely
variable ranging
from
hornblendites
to
leuco-amphibolites, The grayish- to bluish-
geen,
rarely
yellow
hornblendes
are
intensively
dusted
by
opa-
ques.
They
form
large
xenoblasts
which
underwent
post-crys-
talline
deformation.
Plagioclase
mostly
forms
fine-grained,
granoblastic
aggregates
together
with
minor
quartz
and
horn-
blende
(mortar
structure).
Relics
of
igneous
pyroxenes
are
miss-
ing.
Accessories
are sphene,
apatite
and opaques. The rocks are
penetrated
by
alteration zones consisting
of
strongly sericitized
plagioclase and
pale-green
hornblende.
249
Table
1
Metabasites
of
the
Marianske
Lalne
complex
Table
3
Greenschists
and
amphibolites
from
the
southeastern
part
of
the
Domazlice
metamorphic
complex
Probe
57
59
60
61
62
63
64 65 66 67 68
69 70 Probe
17
20
28
29
30
31
32 33 34
SiO, 48.2 48.4
48.5
47.2
49.6
49.8 50.9 53.2 59.1 64.3 47.4 48.3 47.8
TiO, 0.91 1.91 0.82 0.98 1.06 1.84 1.54 1.87 0.72 0.64 1.50 1.30 1.33
SiO~
44.9 46,2 48.3 46.6 48.5
48.3
46.2 48.4 46.9
AI203 18.7 15.3 16.6 17.6 16.1 13.5 14.0 15.8 14.7 15.0 13.8 14.7 lS.1 TiO] 2.47 1.71 3.53 2.41 3.30 2.85 1.79 2.15 2.49
FezO} 0.99 1.27 1.94 2.27 2.53 2.49 1.84 1.87 2.27 1 32
3.67
1.57 0.95
AI"OJ
15.7 17.0 14.3 14.3
14.1
14.1 16.8 16.5 15.6
FeO 6.91 9.38 5.76 6.24 7.16 10.7 9.72 7.44 5.09 5.07 10.2 8.60 9.17 Fez03 2.88 2.17 2.26 0.87 2.08 2.19 1.88 1.67 2.31
MnO 0.13 0.17 0.12 0.13 0.17 0.24 0.19 0.16 0.16 0.14 0.25 0.18 0.17 FeO 8.47 6.77 9.99 11.4 10.7 10.5
8.12
7.12 10.6
MgO 9.57 7.45 8.93 8.66 7.31 7.37 7.36 4.59 5.00 2.26 6.88 7.26 6.98 MnO 0.13 0.13 0.18 0.16 0.24 0.20 0.14 0.13 0.31
CaO 10.1 9.67 12.1 11.7 9.78 10.2 9.07 5.73 6.03 5.72 11.2 12.3 12.7 MgO 6.63 7.08 4.97
8.22
4.22 4.06 9.09 5.89 5.09
Na20 2.71 2.86 2.75 2.97 3.55 2.96 3.39 4.13 2.84 2.97 1.74 2.86 2.92 CaO
8.25 8.58
8.83 8.17 7.53 7.80 9.26 10.7 10.2
K,Q 0.30 0.70 0.18 0.23 0.41 0.02 0.02 1.11 0.98 0.62 0.52 0.25 0.28
Na.>O
3.73
4.21 3.55 2.61 4.10 3.38 3.02 3.87
3.25
P20S
0.12 0.20 0.08 0.09 0.11 0.13 0.08 0.18 0.09 0.19 0.15 0.26 0.24
K"O
0.58
047
0.66 1.02 1.55 2.07 0.79
070
0.92
CO, 0.21 0.05 0.05 0.05 0.37 0.06 0.06 0.68 0.33 0.05 0.10 0.15 0.15 P,O; 0.41 0.27
040
0.42 1.49 1.41 0.32 0.34 0.28
S 0.16 0.05 0.02 0.02 0.02 0.04 0.09 0.12 0.08 0.13 0.02 0.02 0.03 CO, 1.56 1.83 0.31 0.05 0.11 0.59 0.09 0.18 0.11
H,Q 0.7
2.1
1.60 1.6 1.8 0.3 2.6 2.6
2.1
1.0 2 1.7 1.6 S 0.06 0.02 0.02 0.05 0.05 0.05 0.07 0.05 0.05
Summe
99,71 99.46
99.38
99.72
9995
99.63 100.84 99.48
99.49
99.31 99.41 99.45 99.47
HP
4.3 3.7
2.1
3.2 1.7 2.0 2.6 1.6 1.5
Summe
100.07
100.14
99.38 99.43 99.67 99.50 100.17 99.30 99.61
V 125 264
171
194 226 394 359 237
129
111
392 299 293
Cr 280 326 671 273 288 108 178
78
201
<20
134
241
259 V 284
184
514 265 269 204 200 269 337
Ni 183 37 116
145
151
39
61
<20
77
<20
55
106 108
Cr
67 212 53 210
<20 <20
166 199 206
Ab
7 18 3
<2
11
<2 <2
30
31
15
11
9 7
Ni
44 162 18 157
<20
<20
165
26
26
Sr
321 203 256 253
211
71
63 159 176 506
142
294 267
Rb
4 10 8 12 17
21
12 10 10
Y 18 32 22 25 25 52
41
31
29 24
32
41
37
Sr
566 837 356 355 332 706
497
507
136
lr
88
111
39
49 62 100 97 135 72 66 73 89 76 Y
38
27 40 30 58 67 29
31
37
Nb 9 13 5
<3
5 5 6 14 7 8 8 6 8
lr
223 160 219 216
351 371
188 186 173
Ba 137 315 79
61
135 96 47 332
448
369 168 75 73 Nb 25 18 25
21
33
36
17 18 24
Ce
<10
18
<10
<10 <10 <10
25
<10
25
<10
<10
34 20 Ba 273 218 304 347 451
501
233 255 431
Co
49
30
34
48
76 90 38 33 47
Table
2
Amphibolites
of
the
Cerna
Hora
massif
and
the
MYto
area
(M)
Table
4
Gabbroic
rocks
of
the
Neukirchen-Kdyne
(meta-ligneous
complex
Probe
38
46
47
48
49
50
51
52
54
55
41
43
IM) IM)
Probe
324
325 329 330
332
402 413 414 415 420
421
422
Si0
2 49.1 48.7 47.8 46.8 49.5 49.9 47.3 47.1 42.8 47.1 48.1 46.7
Si0
2 49.8 47.7
49.9
48.6
50A
45.7 50.5 48.8 49.4 51.3 47.7 45.6
TiC]
2.24 1.46 1.62 1.14 1.58 1.78 1.46 1.41 1.29 1.28 1.67 1.19
TI0
2 0.34
118
1.14 1.03 0.36 7.82 1.92 1,81 1.70 0.93 0.29 1.03
AI]O]
12.9 14.5 15.1 14.0 14.1 14.8 16.4 16.0
132
13.9 16.1 16.4 AI703 18.0 17.3 17.8 15.2 20.9 13.8 15.7 17.4
179 169
18.2
168
Fe
20J 0.98 1.45 1.21 1.52 2.04 2.25 1.28 1.41 1.6 1.30 2.09 1.21 FeO
tot
6.69
8.46
11.5 10.8 5.31 13.0 11.9 10.9
10.5
6.70 5.42 12.2
FeO 12.2
8.86
9.73
8.45
8.97 8.36 8.04
8.30
8.73
9.14
8.6B 8.98 MnO 0.12 0.15 0.20 0.20 0.10 0.18 0.22 0.17 O.lH
013
0.10 0.10
MnO 0.24 0.17 0.19 0.17 0.18 0.17 0.17 0.18 0.18 0.18 0.16 0.17 MgO 10.3 9.86 6.99 9.12 7.15 6.89 6.76 8.12
7.35
7.06 11.3 10.8
MgO 6.75
8.15
8.39 11.9 8.91 6.69 5.37 5.76 5.45 9.48 6.65 6.71 CaO
8.59 8.79
8A8
10.1 10.3 9.64
8.79
10.1 9.68 12.8 14.2 10.3
CaO 11.1 11.5 12.3 11.9 11.7 10.6 14.0 14.2 17.9 12.8 9.50 12.1 No2O 2.45 2.75 3.50 2.71 3.36 2.26 3.30 3.00 3.20 2.63 1 24 1.52
NazO 1.94 2.65 2.25 1.16 1.61 3.01 2.59 2.29 2.58 1.58 3.89 3.13 K,Q 0.40 0.26 0.14
019
0.21 0.22 0.16 0.14 0.17 0.14 0.11 0.10
K,O 0.09 0.29 0.14 0.28 0.18 0.23 0.07 0.11 0.09 0.09 0.40 0.38
p]OS
0.06
005
0.03 0.03 0.04 0.03 0.22 0.12 0.12 0.10 0.02 0.02
P20S
0.21 0.15 0.20 0.12 0.19 0.25 0.16 0.17 0.41 0.14 0.18 0.09
Summe
9675
96.50
99.68
97.98 98.13 99.54 99.47 100.56
10020
9869
98.58
98.37
CO, 0.11 0.06 0.08 0.14 0.05 0.05 0.71 0.54 4.29 0.20 0.38 0.80 V 49 120
135
224 74
610
245 216 193
368
155
319
S 0.18 0.04 0.02 0.02 0.02 0.02 0.34 0.40 0.32 0.17 0.16 0.11
Cr
135 129 70 204 113
89
123
86
100 442 302 752
H,O 1.5 1.6 1.6 2.3 1.7 1.3 1.6 1.4
1.1
2.1
1.3 1.8 Ni 180 146 45 23
46
<20
23
27
26 < 20 36
177
Sum
me
99.52 99.58 100.61 99.88 100.73
99.34
99.49 99.27 99.94
99.46
99.26 99.77 Cu
21
31
15 16 26 9 18 24 19 20 29 76
V 450 290 298 239 298 296 278 275 235 265 294 227
In
61
71
97 75 42 97 103
80
81
48 42
82
Cr 114 508 463 708 525 349 382 353 253 301 319 370
Rb
13 7
<2
5 6 5 3 3 4 4 5 . 2
Ni 32 188 147 333 206 121 102
114
93 171 12 141
Sr
175 189 258 199 280 183 254 239 253 222 178 108
Ab
<2
5
<2
10
<2
3
~2
<2
<2
3 10 15 Y 12 16 10 14 9 18 24
21
20 17 8 13
Sr
123 139 130 66
89
202 185 157 105 186 152 278
lr
46
45
49
42
14
51
68
66
50
35
16 20
Y 46 38 39
31
41
37
27 35
37
26
27
18 Nb 4 5 5 4 12 8 5 5 5 ·_3 4
lr
137
91
107 73 109 125 103 103 94
84
120 92
Ba
97 80
175
140
72
301
177 126 144 118
51
79
Nb
6 9 9 8 10
11
7 10 9 6 9 'I
Co
,10
< 10
<10
< 10
<10
<10
,,10
,10
<_
1 0 .
'0
.10
. 10
Ba 318 122
125
60 154 152 138
154
43
69
94 42
Ce
<10
<10 <10 <10
14
<10 <10
<10
<10
<10
15 . 10
Amphibolites
of
the
My
to
area
(Table
2)
enriched
in
incompatible
elements,
a
feature
typical
of
modern
within-plate
basalts
or
of
basalts
from
anomalous
mid-ocean
Metabasites
of
the
Marianske
Lazne
The
two
analyzed
amphibolite
samples
from
the
Moldanublan
ridge
segmen1s
IE-MORB).
In
contrast,
sample
37
from
the
Geochemistry
and
the
Cema
Hora
complexes
(Table
1,
2)
of
the My-to area
conform
to
a subalkaline
ocean-floor
tholeiitic
occurence Zadnr Skala near Filipova Hora conforms to a normal
IMORB)
composition
IFig.
3-8).
MORB
character.
Nearly
all anaiyzed
metabasites
of
the
two
complexes
reveal
Analytical
methods
a
chemical
composition
which
compares
well
with
subalkaline
Greenschists
and
amphibolites
in
the
southeastern
ocean-floor
tholeiites. The subalkaline
charakter
is
well
esta-
part
Gabbroic
rocks
of
the
Neukirchen-Kdyne
(meta-)
The
major
elements
Si, Ti, AI,
Fet(Jt,
Mn,
Ca,
K,
P and the trace
blished
by
the
variation
diagrams
Nap,
Kp
vs.
SiO,
IFig. 3)
of
the
Domazlice
metamorphic
complex
(Table
3)
igneous
complex
elements
V,
Cr,
Ni,
Cu,
Zn,
Rb,
Sr,
Y,
lr,
Nb,
Ba,
Ce
were
analyzed
and
Zr/TiO,
vs.
Nb/Y
IFig. 4).
The
TiO,
vs.
FeOw'/MgO
diagram
The
metabasites
of
this
area
exhibit
a
composition
tran-
by
standard
XRF
analysis
using
lithium
tetraborate
fusion
disks
IFig. 5)
and
the
Jensen
cation
plot
IFig. 6)
corroborate
a
tholeiitic
In
their
geochemical
character
the
gabbroic
rocks are sub-
and
powder
pellets
respectively.
Mg
and
Na
were
determined
and
exclude
a calcalkaline
composition
for
the
metabasites.
The
sitional
between
tholeiites
and alkaline basalts. In the
relevant
alkaline
IFig. 3, 4)
and
conform
to
a
tholeiitic
trend
IFig. 5). A
by
standard
AAS
methods
after
decomposing
the
sample
in
only
notable
exception,
sample
67,
is
a
leucocratic
hornblende
discrimination
diagrams
the data
points
plot
either
into
the certain
degree
of
magmatic
differentiation
is
indicated
by
the
HF-HCIO,.
Felll)
was
determined
by
the
vanadate
method
gneiss
of
questionable
origin.
In the
diagram
Ti vs. Zr (Fig.
7)
alkaline
field
(Fig, 3)
or
scatter
around
the
border
line
between
relatively
wide
range
of
FeOtGt/MgO
ratios
and a
conformable
IPeters
1968),
S
by
IR
spectroscopy,
CO,
volumetrically,
and
H,O
nearly
all
analyzed
samples
plot
within
the
field
of
mid-ocean
alkaline and subalkaline
compositions
(Fig. 4). A calcalkaline
variation
in
some
of
the trace
elements
(Fig.
5,
7).
The
Mg-rich
by
the Penfield
method.
Calibration
was
performed
against in-
ridge
basalts.
The
flat
trace-element
patterns
IFig.
8)
are
also
character
can
be
excluded
IFig. 5, 6).
Conformably
these
meta-
gabbroic
rocks are
distinctly
depleted
in
the
incompatible
trace
ternational
reference
samples.
consistent
with
a
MORB-composition.
basites are
similar
to
modern
withinplate
basalts in
their
ch
em
i-
elements
P,
lr,
Ti
and
Y IFig. 8)
and
are
higher
in
Cr.
cal
composition
IFig. 7).
The
trace-element
patterns
IFig. 8)
are
250
251
Table 5
Amphibolites
of
the
Warzenrieth
area
Probe
V
Cr
Ni
Cu
In
Rb
Sr
y
lr
Nb
Ba
Ce
49.6 49.5
0.32 0.31
17.3 20.4
0.46 0.81
4.83
5.10
0.10 0.11
10.1
8.00
12.5 10.2
2.34 3.08
0.06 0.11
0.03 0.03
0.07 0.11
0.12 0.30
1.8
2.2
99.60
100.26
147
963
140
,2
21
16
25
4
~20
<10
96
315
77
<2
433
11
31
4
69
<10
45.6
1.24
16.J
0.32
8.95
0.19
9.03
14.0
1.24
0.17
0.03
0.10
0.32
1.8
99.50
37
47.3
1.39
17.5
1.17
6.04
0.12
7.57
12.6
2.45
0.12
0.13
0.70
0.06
2.2
99.