GeolCarp_Vol65_No3_177

www.geologicacarpathica.com

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

, JUNE 2014, 65, 3, 177—194 doi: 10.2478/geoca-2014-0012

Introduction

The Periadriatic-Balaton Lineament (PABL) is a major dextral
shear zone in the Alpine-Carpathian orogeny that is dividing
the Eastern and the Southern Alps in the west, as well as the
ALCAPA  (Alp-Carpathian-Pannonian)  and  Zagorje-Mid-
Transdanubian  Units  along  its  eastern  section  (Fig. 1).  The
structurally deformed zone of the PABL was a principal chan-
nel of magma and fluid flow in various geotectonic situations,
from  the  Mesozoic  onwards.  The  formation  of  Cretaceous
lamprophyric magmatism (Eisenkappel, Velence Mts), Paleo-
gene  and  Neogene  intermediate  magmatism  (Recsk,  Velence
Mts), diorite intrusions and stratovolcanoes (Zala Basin volca-
nics  in  the  Pannonian  Basin;  Adamello,  Berger  plutons;
Pohorje intrusions in the Alps; Fig. 1) as well as various types
of  mineralization  (Cu-porphyry,  epithermal,  lead-zinc  epige-

Triassic fluid mobilization and epigenetic lead-zinc sulphide

mineralization in the Transdanubian Shear Zone

(Pannonian Basin, Hungary)

ZSOLT BENKÓ

, FERENC MOLNÁR

, MARC LESPINASSE

, KJELL BILLSTRÖM

ZOLTÁN PÉCSKAY

and TIBOR NÉMETH

1,5

Department of Mineralogy, Eötvös Loránd University, Budapest, Hungary; zsoltbenkoo@gmail.com; ferenc.molnar@gtk.fi

University of Lorraine, UMR GeoRessources 7359, CNRS-CREGU BP 239, Bd des Aiguillettes, 54506 Vandoeuvre les Nancy Cedex,

France; marc.lespinasse@univ-lorraine.fr

Laboratory of Isotope Geology, Swedish Natural History Museum, Stockholm, Sweden; kjell.billstrom@nrm.se

Institute of Nuclear Research, Hungarian Academy of Sciences, Debrecen, Hungary; zoltan.pecskay@gmail.com

Institute for Geochemical Research, Hungarian Academy of Sciences, Budapest, Hungary; ntibi@geochem.hu

(Manuscript received November 28, 2013; accepted in revised form March 11, 2014)

Abstract: A combined fluid inclusion, fluid inclusion plane, lead isotope and K/Ar radiometric age dating work has been
carried out on two lead-zinc mineralizations situated along the Periadriatic-Balaton Lineament in the central part of the
Pannonian Basin, in order to reveal their age and genetics as well as temporal-spatial relationships to other lead-zinc-
fluorite mineralization in the Alp-Carpathian region. According to fluid inclusion studies, the formation of the quartz-
fluorite-galena-sphalerite veins in the Velence Mts is the result of mixing of low (0—12 NaCl equiv. wt. %) and high
salinity (10—26 CaCl

equiv. wt. %) brines. Well-crystallized (R3-type) illite associated with the mineralized hydrother-

mal veins indicates that the maximum temperature of the hydrothermal fluids could have been around 250 °C. K/Ar
radiometric ages of illite, separated from the hydrothermal veins provided ages of 209—232 Ma, supporting the Mid- to
Late-Triassic age of the hydrothermal fluid flow. Fluid inclusion plane studies have revealed that hydrothermal circulation
was regional in the granite, but more intensive around the mineralized zones. Lead isotope signatures of hydrothermal
veins in the Velence Mts (

206

Pb/

204

Pb = 18.278—18.363,

207

Pb/

204

Pb = 15.622—15.690 and

208

Pb/

204

Pb = 38.439—38.587)

and in Szabadbattyán (

206

Pb/

204

Pb = 18.286—18.348,

207

Pb/

204

Pb = 15.667—15.736 and

208

Pb/

204

Pb = 38.552—38.781) form

a tight cluster indicating similar, upper crustal source of the lead in the two mineralizations. The nature of mineralizing
fluids, age of the fluid flow, as well as lead isotopic signatures of ore minerals point towards a genetic link between
epigenetic carbonate-hosted stratiform-stratabound Alpine-type lead-zinc-fluorite deposits in the Southern and Eastern
Alps and the studied deposits in the Velence Mts and at Szabadbattyán. In spite of the differences in host rocks and the
depth of the ore precipitation, it is suggested that the studied deposits along the Periadriatic-Balaton Lineament in the
Pannonian Basin and in the Alps belong to the same regional scale fluid flow system, which developed during the advanced
stage of the opening of the Neo-Tethys Ocean. The common origin and ore formation process is more evident considering
results of large-scale palinspastic reconstructions. These suggest, that the studied deposits in the central part of the Pannonian
Basin were located in a zone between the Eastern and Southern Alps until the Early Paleogene and were emplaced to their
current location due to northeastward escape of large crustal blocks from the Alpine collision zone.

Key words: Triassic, Velence Mts, Szabadbattyán, Periadriatic-Balaton Lineament System, lead isotopes, fluid inclu-
sions, Alpine-type epigenetic lead-zinc mineralization.

netic at Recsk and in the Velence Mts) is clearly or apparently
controlled by the repeated reactivation of this fault system.

Along the eastern segment of the PABL, in the central part

of  the  Pannonian  Basin  two  Paleozoic,  allochthonous  com-
plexes,  the  Szabadbattyán  Block  and  the  Velence  Mts  crop
out. The western part of the Velence Mts is built up of early
Permian  monzogranite,  which  is  the  host  of  vein-type  fluo-
rite-galena-sphalerite-calcite mineralization (hereinafter base-
metal-fluorite  veins).  The  near-by  (30 km)  Szabadbattyán
Block  is  composed  of  structurally  deformed  Paleozoic
metasedimentary rocks and Triassic andesitic intrusions. The
Devonian  limestone  at  Szabadbattyán  is  host  of  vein-,  and
metasomatic-type Pb mineralization.

The age and origin of both mineralizations have been con-

troversial for a long time (Velence Mts: Jantsky 1957; Kas-
zanitzky 1958; Horvát Ódor 1984; Molnár 1996, 2004,

178

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Fig. 1. Geological overview map of the Alp-Carpathian region compiled after Kovács et al. (2007) and Köppel (1983). Abbreviations: Faults:
PABL – Periadriatic Balaton Lineament System. Epigenetic lead-zinc deposits along the PABL: Sal – Salafossa, Blei – Bleiberg. Paleo-
gene plutons and volcanites: A – Adamello Pluton, B – Bergell Pluton, ZB – Zala Basin, R – Recsk. Carboniferous to Permian granite
intrusions along the PAL: a – Bressanone Pluton, b – Eisenkappel Pluton, c – Buzsák, d – Ságvár, Ka – Karawanken Mts. Tectonic
units: ZMTU – Zagorje—Mid Transdanubian Unit.

Table 1: Summary of magmatic and hydrothermal processes and their characteristics in the Velence Mts and Szabadbattyán Block.

179

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

Szabadbattyán: Kiss 1951; Földvári 1952; Kiss 2003), due to
their allochthonous, exotic positions along the PABL.

In order to shed further light on the timing, nature of ore-

forming  processes  and  paleogeographical  relations  of  the
mineralizations in the two Paleozoic units we have adopted a
multi-method  approach.  Fluid  inclusion  microthermometry
as well as a new method, called Fluid Inclusion Plane (FIP)
technique have been performed to extend the existing know-
ledge about the nature of ore-forming fluids and enable a dis-
cussion  on  the  depth  of  ore  formation.  Lead  isotope  data
were collected in order to elucidate the timing and the origin
of the Pb components in the ore. Furthermore, we have car-
ried out K/Ar radiometric age determinations on hydrother-
mal  clay  mineral  assemblages  and  a  rock  forming  mineral
surrounding the veins for a better determination of age con-
straints of ore formation.

Regional geology and hydrothermal processes

The Velence Mts are located along the southern part of the

Alcapa Megaunit and the northern side of the PABL (Fig. 1).
The  Alcapa  Megaunit  is  composed  of  the  metamorphosed
Proterozoic to Mesozoic blocks of the Eastern Alps, the Paleo-
zoic low-grade metamorphic and Mesozoic carbonaceous se-
quences  of  the  Transdanubian  Mountain  Range  (TMR),  the
Bükk Mts, as well as the crystalline blocks of the Inner West-
ern  Carpathians  (Fig. 1).  By  the  Oligocene—Early  Miocene,
the Alcapa Megaunit escaped northeastward from the Alpine
collision zone (Kázmér & Kovács 1985; Csontos et al. 1992;
Fodor  et  al.  1998;  Haas  et  al.  2000).  The  total  350—400 km
present day offset can be attributed to the Paleogene to Mid-
Late Miocene extension, lateral extrusion and counter-clock-
wise rotation of the Alcapa Megaunit (Tari 1996; Csontos &

Fig. 2. Geology of the Velence Mts, modified after Dudko (1999) with sample localities of the current study.

180

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Vörös 2004). Along the PABL, Paleozoic and Paleogene
units can be regarded as allochthonous blocks in a tectonic
mega-mélange between the Alcapa and Zagorje-Mid-Trans-
danubian Unit (Fig. 1).

The Velence Mts consist of two major units: the western unit

is a Permian monzogranite intrusion; the eastern unit is an Early
Oligocene intrusive-volcanic complex of intermediate composi-
tion (Fig. 2). The granite intrusion can be further divided into
two blocks. The boundary between the eastern and the western
part of the granite intrusion is the Pákozd Line which is a post-
Triassic normal fault (Benkó 2008). The complete sequence of
magmatic and hydrothermal events and p-T conditions of the
different processes are summarized in Table 1.

The Permian granite is an A-type, peraluminous biotitic

monzogranite  (Uher  &  Broska  1994,  1996;  Broska  &  Uher
2000; Finger et al. 2003), which intruded into an early Paleo-
zoic  anchimetamorphic  slate  at  274—290 Ma  (Balogh  et  al.
1983; Buda 1985; Buda et al. 2004). The results of mineral-
ogical and fluid inclusion studies by Molnár (1997) suggested
that  the  superimposing  quartz-molybdenite-pyrite-grey  ore
stockwork  mineralization  along  the  contact  of  the  granite
and the shale was linked to the post-magmatic hydrothermal
system of the granite.

The N—S and NE—SW striking base-metal-fluorite veins

occur in the western part of the granite body of the Velence
Mts  (Fig. 2).  These  veins  are  surrounded  by  argillic  alter-
ation  (illite,  kaolinite,  smectite)  envelopes  (Nemecz  1973;
Benkó  2008).  Galena  and  sphalerite  are  co-genetic  phases,
whereas  fluorite  is  partially  co-genetic,  and  partly  younger
than  other  ore  minerals.  Characteristic  ore  textures  are  co-
cade  and  brecciated  (Jantsky  1957).  According  to  sulphur
isotope  studies  (Benkó  2008)  the  maximum  temperature  of
ore formation was around 230—250 °C.

By the time of the Late Cretaceous, the granite was intruded

by monchiquite-spessartite dykes (Horváth & Ódor 1984).
These dykes were K/Ar dated at 77.6 ± 30 Ma (Balogh et al.
1983). The dykes are not altered and they did not generate
hydrothermal alteration in the granite host.

In the eastern part of the Velence Mts, a hydrothermally

altered  and  eroded  andesitic  stratovolcanic  structure  (dated
by the K/Ar method at 28—30 Ma; Bajnóczi 2003) crops out
and  this  unit  is  underlain  by  diorite  intrusions  (Fig. 2).  The
Paleogene  calc-alkaline  igneous  rocks  are  characterized  by
medium- to high-K content and they are regarded as results
of  syn-  to  post-syncollisional  magmatism,  which  occurred
by the collision of the Apulian Microplate (of African origin)
and the European Plate (Darida-Tichy 1987; von Blancken-
burg 1995; Benedek 2002; Benedek et al. 2004).

In the Paleogene Volcanic Unit of the Velence Mts, Cu-por-

phyry and minor skarn mineralization is spatially linked to
the diorite intrusion whereas alteration zones typical for
high-sulphidation type epithermal systems are known in the
outcrops of the stratovolcano (Molnár 1996, 2004; Bajnóczi
et al. 2002; Bajnóczi 2003).

The hydrothermal system of the Paleogene age has also in-

teracted with the Permian granite intrusion in the eastern part
of the Velence Mts, east of the Pákozd Line (Molnár 2004;
Benkó & Molnár 2004; Benkó et al. 2012). Secondary fluid
inclusions  that  are  attributed  to  the  Paleogene  fluid  circula-
tion in the old granite can easily be recognized in rock form-
ing quartz, because the Paleogene fluid circulation took place
under  low  pressure  (max.  150—200 bar)  boiling  conditions
resulting  in  common  occurrences  of  vapour  phase-rich  and
liquid phase-rich (sometimes halite bearing) fluid inclusions.

The Szabadbattyán Block is a thrusted unit composed of

metamorphosed slate, phyllite, and carbonate nappes (Fig. 3).
Igneous activity is marked by the presence of Carboniferous
granite  porphyry  dykes,  whereas  andesite  dykes  of  Triassic
age  (K/Ar  data  from  Balogh  et  al.  1983  and  Bagdaszarjan
1989)  intrude  the  Polgárdi  Limestone  Formation  (Table 1).
The epigenetic base-metal mineralization occurs in fractures
and  as  roughly  bedding—parallel  metasomatic-replacement
bodies in the Polgárdi Limestone Formation. The major ore
mineral is galena. Bournonite, sphalerite, chalcopyrite, tetra-
hedrite and native silver are the most common minerals asso-
ciated with galena (Szakáll & Molnár 2003).

Fig. 3. Section of the Szabadbattyán area (Fülöp 1990).

181

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

Sampling and analytical methods

There are no outcrops of the discussed mineralizations

therefore no detailed field work has been carried out on these
formations. Mineralized samples were collected from the
historical Mineralogical Collection of the Eötvös Loránd
University, Budapest. Sample localities of rock samples are
summarized in Fig. 2.

Fluid inclusion studies have been carried out on quartz,

fluorite  and  sphalerite  from  the  base-metal-fluorite  veins  in
the Velence Mts. For comparison, we also analysed second-
ary  fluid  inclusions  in  rock  forming  quartz  from  unaltered
granite  and  from  the  alteration  halo  of  the  hydrothermal
veins.  To  establish  the  relationships  between  argillic  alter-
ation  zones  and  fluid  inclusion  assemblages  responsible  for
their formation, the FIP method was applied. In order to de-
termine the extension of the hydrothermal fluid flow, and the
rock  volume  affected  by  the  hydrothermal  system,  fluid  in-
clusion  thermometry  and  FIP  studies  have  been  carried  out
on the inclusions of the rock forming quartz crystals. Details
of  the  FIP  method  have  been  published  in  Lespinasse  &
Pecher (1986), Lespinasse & Cathelineau (1990), Lespinasse
et al. (2005). Briefly, FIP are Type III extensional microfrac-
tures that form always perpendicular on the minimum stress
axes of the stress field in rock forming quartz crystals of gra-
nitic rocks. If the age of the fluid circulation and hence the
age  of  the  FIPs  is  known  one  can  determine  the  minimum
stress axes of the stress field during fluid flow and mineral-
ization. Another advantage of the method is that FIP density
(number  of  FIP  per  unit  surface,  expressed  in  1/mm

—2

and

cumulative length per unit surface expressed in mm/mm

) in

the  rock  forming  quartz  crystals  displays  a  systematic  in-
creasing  trend  towards  the  alteration  zones  (e.g.  argillic  al-
teration zones, vein swarms; Benkó et al. 2008). Using this
approach,  secondary  fluid  inclusions  in  magmatic  quartz
crystals of granite can be directly related to certain alteration
zones (e.g. argillic alteration) that do not contain hydrother-
mal  minerals  with  primary  fluid  inclusions.  Fluid  inclusion
assemblages and FIP density were analysed by the computer
code AnIma (Lespinasse et al. 2005), developed at the Uni-
versity of Lorraine, Nancy, France.

Fluid inclusion microthermometric studies were carried

out on a Chaixmeca heating—freezing stage. The studies have
yielded  reproducible  temperatures  within  ± 0.1 °C  (below
0 °C) and  ± 1 °C (above 0 °C), respectively. The equipment
was  standardized  with  synthetic  fluid  inclusions  (H

O—CO

and pure water) of known microthermometric properties (i.e.
triple point temperature for pure CO

at —56.6 °C, melting

temperature of ice at 0 °C).  Thin sections  used for fluid in-
clusion petrography and microthermometry were double pol-
ished  100—150 µm  thick.  Characteristic  isochors  were
calculated  using  the  equations  of  Zhang  &  Frantz  (1987).
The salinities of the aqueous fluid inclusions were calculated
using  the  experimental  equation  of  states  of  Oakes  et  al.
(1990) and Bodnar (1993).

K/Ar radiometric age determinations were carried out at

the Institute of Nuclear Research of the Hungarian Academy
of Sciences. Details of the analytical methods can be found
in Balogh (1985). Clay mineral phases were collected from

alteration  selvages  of  base-metal-fluorite  veins  cutting  the
granite and from NE—SW trending clay mineral filled veins.
Purity  and  composition  of  the  mineral  fractions  were  con-
trolled  by  X-ray  powder  diffraction  (XRPD).  After  careful
separation and mild crushing, the samples were suspended in
water glass columns for 200 minutes. Following Stoke’s law
we  then  extracted  the  portion  of  the  suspension  which  con-
tained  the  < 2 µm  size  clay  mineral  fraction.  This  fraction
has  the  greatest  surface  area/volume  ratio  and  hence  is  the
most susceptible to diffusion of radiogenic Ar. Nevertheless,
several  authors  presented  meaningful  K/Ar  age  data  also
from  < 0.2 µm  and  < 0.1 µm  size  fractions  (e.g.  Zhao  et  al.
1997; Zwingmann et al. 2010), especially from sedimentary-
diagenetic environments and from shallow fault gauges.

The mineral composition of the clay fraction was deter-

mined  on  the  separated,  randomly  oriented  powder  samples
by  semi-quantitative  phase  analysis.  Three  aliquots  of  each
sample were separated for diagnostic treatments. Clay miner-
als were identified by XRD diagrams obtained from parallel-
oriented specimens. Diagnostic treatments were carried out for
the  identification  and  characterization  of  the  clay  minerals.
Samples  were  treated  by  ethylene-glycol  at  60 °C  overnight
for  the  detection  of  swelling  clay  minerals  and  mixed  layer
clay  minerals.  Magnesium  saturation  followed  by  glycerol
solvation at 95 °C overnight was used to distinguish smectite
and vermiculite. Layer charge of swelling clay minerals was
estimated  by  potassium  saturation.  Chlorite-kaolinite  dis-
tinction is based on heating of the samples at 350 and 550 °C
for  2  hours.  The  tetrahedral  or  octahedral  origin  of  layer
charge  was  determined  by  the  Greene-Kelly  test  (Greene-
Kelly  1953).  XRPD  measurements  were  carried  out  using  a
Philips PW 1710 diffractometer with CuK

α radiation at 45 kV

and 35 mA in the lab of the Institute for Geological and Geo-
chemical Research of the Hungarian Academy of Sciences.

Lead isotope measurements were performed on pure galena,

calcite  and  fluorite  crystals  collected  from  the  base-metal-
fluorite veins. Minerals were separated by hand picking under
stereomicroscope. The analytical part followed routines adapted
at  the  Swedish  Museum  of  Natural  History,  Stockholm
(DeIgnacio et al. 2006). After dissolution in acids and subse-
quent ion exchange routines, clean lead separates were yielded.
The  isotopic  analyses  were  carried  out  using  a  Micromass
Isoprobe ICP-mass spectrometer in the Swedish Museum of
Natural History, Stockholm. Mass bias corrections were ac-
counted  for  by  using  an  internal  Tl  normalization,  and  NBS
981  were  run  repeatedly  to  secure  data  accuracy.  Typically,
the precision (2

σ error) of Pb runs is ±0.10 % or better.

Results

Fluid inclusion petrography and microthermometry

Relatively large (10—20 µm) two phase, liquid—vapour fluid

inclusions ratios were detected along the growth zones and
in isolated clouds in hydrothermal quartz, in fluorite and in
sphalerite crystals in the base-metal-fluorite veins (Fig. 4a,b).
The phase ratio between vapour and liquid phases is around
0.1 in the samples from west of the Pákozd Line and around

182

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOLOGICA CARPATHICA

GEOLOGICA CARPATHICA, 2014, 65, 3, 177—194

0.2  in  the  samples  from  east  of  the  Pákozd  Line  in  the
hydrothermal  quartz.  Fluid  inclusion  data  are  listed  in  the
Appendix  (as  a  Supplement  in  the  electronical  version;
www.geologicacarpathica.com).

Two phase liquid-vapour primary fluid inclusions in fluorite

from  the  base-metal-fluorite  veins  homogenized  into  liquid
phase at temperatures of 90—130 °C in the western block of
the granite (e.g. west of the Pákozd Line, Fig. 5a). Consider-
ing the eutectic melting temperatures of ice at around  —21 °C,
their  compositions  can  be  modelled  in  the  NaCl—H

O sys-

tem. Melting temperatures of ice are distributed between
—5.1 °C and —9.8 °C corresponding to 8—13 NaCl equiv.
wt. % salinities.

Fig. 4.  a  –  Base-metal-fluorite
vein with cocade texture from the
Velence  Mts.  The  brecciated  and
altered  (illite-kaolinite-smectite)
granite  is  cemented  by  quartz
(white  with  concentric  zonation)
and sphalerite (brown). The white
circle  indicates  the  place  of  fluid
inclusion  studies;  b  –  Primary
two  phase  (L + V;  liquid-vapor)
fluid  inclusions  along  growth
zones in sphalerite;  c – Second-
ary,  two-phase  (liquid-vapour)
fluid inclusions in rock forming
quartz  crystals  of  the  granite.
The  vapour/liquid  ratio  is  0.2.
Fluid inclusions are aligned along
fluid  inclusion  planes;  d  –  Sec-
ondary,  two—phase  (liquid—va-
pour)  fluid  inclusions  in  rock
forming  quartz  crystals  of  the
granite.  The  vapour/liquid  ratio
is  0.1;  e  –  NE—SW  trending
argillic  alteration  zone  in  the
western block of the granite. The
central part of the alteration zone
is  greenish  due  to  the  smectite
whereas  the  rim  is  rather  white
because  of  the  higher  relative
amount of illite; f – FIP in rock
forming quartz in unaltered gran-
ite. FIP are short and the number
of  FIP  in  a  certain  area  is  low;
g – FIP in quartz crystals in al-
tered  granite.  FIP  are  long  and
the number of FIP is high.

Two phase liquid—vapour primary fluid inclusions in

sphalerite homogenized at 80—160 °C in the western unit of
the granite (Fig. 5d). Due to their very low eutectic and ice
melting temperatures, partly below —60 °C and below
—21 °C, respectively, their compositions cannot be modelled
in the NaCl—H

O system. Because of difficulties with the re-

producible observations of hydrohalite melting, the fluid
composition has been modelled in the CaCl

—H

O system.

Melting of ice took place from —14.8 to —24.5 °C, and the cal-
culated salinities are between 18 and 23 CaCl

equiv. wt. %.

Primary, two-phase fluid inclusions in the hydrothermal

quartz homogenize at 80—130 °C west of the Pákozd Line
and 170—220 °C east of the Pákozd line (Fig. 5d). Eutectic

183

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

melting in these inclusions started below —50 °C. Therefore
salinities of these inclusions were calculated in CaCl

equiv.

wt. %. Final melting temperatures in the inclusions west and
east of the Pákozd Line varied from —6.2 °C to —26.4 °C and
from —4.3 °C to —21.7 °C, respectively. These final melting
temperatures correspond to salinities from 10—25 CaCl

wt. %

and 7—21 CaCl

wt. %.

Fig. 5. Homogenization temperature distribution diagram of the measured fluid inclusions in fluorite, sphalerite, hydrothermal quartz, as
well as in the rock forming quartz crystals of the granite from the Velence Mts. a—b—c – fluid composition is modelled in the NaCl—H

system; d—e—f – fluid composition is modelled by CaCl

—H

O system. c. – concentration.

Secondary fluid inclusions with similar phase ratios also

occur in the rock forming quartz of the granite. Independently
of the distance from the alteration zones, these inclusions are
regionally present in the granite. However, density of FIP is
high in the close vicinity of the veins (53.2—125.1 1/mm

and

11.3—26.0 mm/mm

; Fig. 4e,f) and decreases to the less

altered granite (23.9—51.9 1/mm

and 4.5—6.9 mm/mm

;

184

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Table 2; Fig. 4, e.g). The orientation of the fluid inclusion
planes is always parallel to the strike of the base-metal-fluo-
rite veins (NE—SW; Benkó 2008).

One group of secondary fluid inclusions in rock-forming

quartz of fresh and argillic altered granite is characterized by
eutectic  melting  temperatures  at  around  —21 °C.  The  salini-
ties calculated from the melting temperatures of the ice (—0.2
to  —8.6 °C)  are  in  the  range  of  0.3—12 NaCl  equiv.  wt. %.
Homogenization  of  these  inclusions  took  place  into  liquid
phase at 70—230 °C and 170—260 °C in the western and east-

ern blocks of the granite, respectively. The median of the ho-
mogenization temperatures is around 130 °C in inclusions
west of the Pákozd Line and around 210 °C east of the
Pákozd Line (Fig. 5b,c).

Another group of secondary fluid inclusions in rock—form-

ing quartz of fresh and argillic altered granite displayed eu-
tectic melting temperatures from —49 to —56 °C with melting
temperatures of the ice between —32.3 °C and —13.6 °C.
These fluid inclusions were also modelled in the CaCl

—H

system thus calculated salinities are between 9.9 and
25.8 CaCl

equiv. wt. %. Homogenization temperatures are

50—180 °C and 160 °C —260 °C east and west of the Pákozd
Line, respectively. The median of the homogenization tem-
peratures varies similarly to the low salinity secondary fluid
inclusions. In the western and eastern block the median is
around 135 °C and around 220 °C, respectively (Fig. 5e,f).

Lead isotope data

Lead isotope analyses have been carried out on galena

(n = 4), fluorite (n = 4) and calcite (n = 2) from the base-metal-
fluorite veins of the Velence Mts and from vein filling galena
(n = 4) from the Polgárdi Limestone Formation of the Sza-
badbattyán Block (Figs. 2 and 3). In the Velence Mts, the

Table 3: Lead isotope data of the lead-zinc mineralization in the Velence Mts and at Szabadbattyán. S—K – Stacey & Kramers (1975)
model age; C—R – Cummings & Richards (1975) model age.

Sample number

Analysed
mineral

Area

206

Pb/

204

207

Pb/

204

208

Pb/

204

Pb µ

value

S-K model

age (Ma)

C-R model

age (Ma)

BE50301

galena Velence

Mountains

18.288 15.679 38.587 10.06 412

310

BE50806

galena Velence

Mountains

18.278 15.653 38.506

9.95 369

310

BE303030

galena Velence

Mountains

18.305 15.622 38.439

9.80 286

300

BE51339

galena Velence

Mountains

18.268 15.645 38.481

9.91 360

330

BE51041

galena Velence

Mountains

18.363 15.690 38.599

BE51659

galena Velence

Mountains

18.318 15.660 38.466

BE50691

galena Velence

Mountains

18.313 15.654 38.443

51045

fluorite

Velence

Mountains

18.438 15.657 38.703

50691

fluorite

Velence

Mountains

18.511 15.697 38.547

50301

fluorite

Velence

Mountains

18.325 15.660 38.499

51041

fluorite

Velence

Mountains

18.457 15.665 38.770

M06

calcite Velence

Mountains

18.366 16.658 38.545

M30

calcite Velence

Mountains

18.351 15.663 38.494

BE50269

galena Szabadbattyán

18.286 15.667 38.552 10.01 390

310

BE51654

galena Szabadbattyán

18.339 15.710 38.694 10.19 435

290

BE51664

galena Szabadbattyán

18.348 15.736 38.781 10.30 477

280

BE50300

galena Szabadbattyán

18.293 15.679 38.588 10.06 408

310

accuracy: ± 0.10 %

Locality

Rock type and type of
hydrothermal alteration

Selected mineral
fraction

K-content (%)

Ar rad/g(cm

/g)

Ar rad

(%)

K/Ar age

(million year)

Pákozd, Big quarry

granite, argillic alteration

illite, kaolinite,
smectite

5.010 4.5827x10

–5

90.20 221.2±6.7

Pákozd, “Pegmatite quarry” granite, argillic alteration

illite, kaolinite,
smectite

4.214 3.6442x10

–5

89.30 209.8±3.7

Székesfehérvár, Kisfalud
quarry, next to the aplite
vein

granite, argillic alteration

illite, kaolinite,
smectite

3.185 2.8262x10

–5

75.00 214.6±6.7

Székesfehérvár, Kisfalud
quarry

granite, argillic alteration

illite, kaolinite,
smectite

3.260 3.038x10

–5

97.30 232.3±5.1

Sukoró, Rigó-hill

granite, no alteration

orthoclase

9.747

8.9088x10

–5

89.60 220.9±6.7

Table 4: K-Ar radiometric ages of hydrothermal and rock forming minerals from the Velence Mts and Szabadbattyán.

FIP density

Locality

Number of

FIP/unit area

Summa lenght

of FIP/unit area

77.2

11.8

125.1

73.9

13.7

Center of illite-
kaolinite-smectite
alteration zones

53.2

11.3

38.9

6.13

23.9

4.5

31.2

6.9

Out of alteration
zones

51.9

6.26

Table 2: Fluid inclusion plane density data, measured in the rock
forming quartz crystals of the Velence Mts granite.

185

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

lead isotope data obtained for galena are as follows:

206

Pb/

204

Pb = 18.278—18.363,

207

Pb/

204

Pb = 15.622—15.690

and

208

Pb/

204

Pb=38.439—38.587 (Table 3). Lead isotope ratios

for galena from the Szabadbattyán Block are slightly higher:

206

Pb/

204

Pb = 18.286—18.348,

207

Pb/

204

Pb = 15.667—15.736 and

208

Pb/

204

Pb = 38.552—38.781. However, these data are margin-

ally different to those from the Velence Mts only, taking the
analytical uncertainties into consideration. The results for cal-
cite and fluorite from the base-metal-fluorite veins of the Ve-
lence Mts are close to, but typically slightly more evolved
than those for galena of the same veins (Table 3).

Thus, the isotope data from the two areas form a tight clus-

ter and, besides, one can note a tendency towards a linear ar-
ray (Table 3).

When treated together, the galena data from the two areas

yield µ values of 9.8—10.3 (Table 3), following the S-K model
(Stacey & Kramers 1975). This is higher than the average
crustal value (µ

= 9.74), and a dominant upper crustal

source for ore lead is also indicated by the plumbotectonic
model of Zartman & Doe (1981). Model ages, based on the

206

Pb/

204

Pb and

207

Pb/

204

Pb data for the combined galena

data set are quite consistent at around 300 Ma when the
Cumming & Richards (1975) model is applied, whereas S-K
model ages vary considerably (286—477 Ma).

XRPD results and clay mineralogy

Fig. 6. Radiometric age dates measured on different mineral fractions in the Velence Mts and at the
Szabadbattyán Block.

XRPD analyses were carried

out  on  the  clay  mineral  assem-
blage  of  the  argillic  alteration
halo of the granite-hosted hydro-
thermal base-metal-fluorite veins
in the Velence Mts. Argillic alter-
ation  zones  without  base  metal
mineralization  along  NE—SW
trending faults were also studied.
The  colour  of  alteration  zones
changes  from  the  fresh  granite
towards  the  central  part  of  the
alteration  zones:  the  central
parts  are  more  greenish,  while
the lateral parts of the alteration
are  dominated  by  white  clay
minerals (Fig. 4a). According to
the  XRPD  studies  the  green  co-
loured  clay  is  dioctahedral
smectite  with  calcium  and/or
magnesium  in  the  interlayer
space.  The  basal  reflection  is
shifted  from  15 Å  to  12.6 Å  af-
ter  potassium  saturation,  indicat-
ing  the  low-layer  charge  of  the
smectite.  The  Greene-Kelly  test
indicates  that  this  charge  arises
from  isomorphic  substitution  in
the  octahedral  sheet  (Greene-
Kelly  1953).  These  results  show
that the smectite is a low charged
montmorillonite.  Besides  mont-

morillonite, illite/montmorillonite, white coloured mixed layer
clay mineral containing 15—20 % illite, pure illite and kaolin-
ite are also present. Illite crystallinity has been checked by
combined XRPD and IR spectroscopic analyses (Benkó 2008)
and both methods have indicated a well—crystallized R3-type
illite based on the classification scheme of Środoń (1984).

K—Ar radiometric ages

K/Ar ages for illite (n = 4) are between 209.8 and

232.3 Ma, with individual errors in the order of ± 10 Ma, or
less. One K-feldspar from the relatively fresh granite (sam-
ple 6620) yielded an age of 220.9 Ma, which is comparable
to the ages of the illite (Table 4, Fig. 6).

Discussion

Our studies suggest that petrographic, fluid inclusion and

isotope data do not support old genetic models stressing that
base-metal-fluorite mineralization in the Velence Mts can be
related to the formation of the granite.

Nature of the ore-forming fluids

The petrography of fluid inclusions in the Velence Mts

suggest trapping from a homogeneous parental fluid, there-

186

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

fore the measured homogenization temperatures are only
minimum estimates of the trapping conditions. True trapping
temperatures and pressures can be obtained only by pressure
correction using an independent thermometer.

Field evidence combined by the XRPD results indicates that

illite (white) was the first phase to form due to fluid/rock in-
teraction,  followed  by  kaolinite  (white)  and  smectite  (green)
as  gradual  opening  of  the  faults  proceeds.  In  hydrothermal
systems  clay  mineral  assemblages  are  useful  for  temperature
estimation (Reyes 1990; Hedenquist & Lowenstern 1994; Parry
&  Jasumback  2002).  Pure  illite  forms  above  220—250 °C,
while kaolinite and smectite form below 180 (200) °C. Conse-
quently,  it  may  be  suggested  that  mineralization  in  the  Ve-
lence  Mts  started  at  temperatures  above  250 °C,  resulting  in

illite alteration, and with gradual cooling of the fluids below
200 °C there was a formation of kaolinite and smectite. Sul-
phur isotope analyses on syngenetic galena-sphalerite mineral
pairs also provided temperatures around 230—250 °C (Benkó
2008), which support the view that the maximum temperature
of the hydrothermal system could be around 250 °C.

Fluid inclusions with NaCl—H

O and CaCl

—H

O model

compositions are simultaneously present as primary objects in
the hydrothermal quartz and fluorite in the Velence Mts and as
secondary inclusions in the rock-forming quartz of the granite.
In spite of the compositional differences, their homogeniza-
tion temperature distributions in all outcrops are the same and
the number of their FIP increases towards the alteration
zones. If we assume that these inclusions relate to the cool-

Fig. 7. Temperature—pressure conditions of fluid inclusion entrapment in the Triassic and Alpine hydrothermal systems of the Velence Mts.
Isochors were calculated on the basis of equations of Zhang & Frantz (1987). c. – concentration.

187

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

ing  of  the  granite  which  crystallized  at  2 kbar  (Buda  1993;
Fig. 7), the isochores for the low homogenization temperature
(Th ~ 90—120 °C)  inclusions  should  have  crossed  the  2 kbar
isobar  at  150—220 °C.  This  low  temperature  at  6—8 km,  ac-
cording to the 2 kbar pressure, assumes a very low geothermal
gradient  (20 °C/km).  In  the  case  of  a  cooling  granite  body,
a higher temperature than the average (35 °C/km) geothermal
gradient  is  expected.  Therefore  the  observed  fluid  inclusion
features is difficult to relate to the postmagmatic-hydrothermal
system of the granite as it was suggested by Jantsky (1957).

The estimated geothermal gradient during the Triassic was

45 °C/km  (Schuster  et  al.  1999).  Intersecting  the  Triassic
(45 °C/km) geotherm calculated for hydrostatic and lithostatic
conditions  with  the  isochors  of  the  fluid  inclusions  from  the
eastern  block  of  the  granite,  the  obtained  pressures  are  be-
tween  400  and  1200  bars.  Intersecting  the  isochors  of  the
higher  homogenization  temperature  group  (eastern  block;
210—220 °C) with the 250 °C isotherm (which is the assumed
maximum  temperature  for  illite  crystallization;  Reyes  1990;
Hedenquist  &  Lowenstern  1994;  Parry  &  Jasumback  2002),
results  in  pressures  around  400  bar  (Fig. 7).  This  pressure  is
lower than the estimated pressure at the time of the formation
of the granite, higher than the pressure range for the Paleogene
hydrothermal  system  (30—280 bar,  Molnár  1996;  Fig. 7)  and
equivalent to the pressure calculated by the interception of the
isochors  and  the  Triassic  (hydrostatic)  geotherms  (Fig. 7).
Therefore it is assumed that the pressure conditions during the
fluid circulation could be near-hydrostatic. Differences in ho-
mogenization temperatures between the eastern and the west-
ern block of the granite can be explained by post-hydrothermal
tectonic activity of the Pákozd Line (Benkó 2008).

In petrography the fluid inclusion assemblages associated

with the Paleogene intrusive-volcanic activity in the eastern
part of the Velence Mts are significantly different from the fluid
inclusion assemblages in the western part of the granite (e.g.
boiling of low-, and high-salinity fluids with temperatures be-
tween 250 °C and 450 °C; Molnár 2004; Fig. 7), therefore we
proceed to explore the possibility that all of the studied fluid
inclusion populations are linked to a third fluid flow event in-
dependent from those in the Paleogene and Permian.

Fluid inclusion data for Alpine-type epigenetic lead-zinc

ore  deposits  hosted  by  Triassic  carbonate  rocks  along  the
PABL  in  the  Drau  Range  (Mežica,  Bleiberg)  are  similar  to
our results for the mineralization of the Velence Mts (Fig. 8).
The Alpine-type epigenetic Pb-Zn ore deposit is a subtype of
the carbonate hosted stratabound Pb-Zn mineralizations. The
mineralization  is  epigenetic,  hosted  by  Ladinian—Carnian
limestones in the Eastern and Southern Alps. The ores have
simple mineralogy, containing galena, sphalerite, pyrite and
marcasite. Zeeh et al. (1998) reported that the temperature of
the hydrothermal fluids of the first ore phase ranged between
122 °C and 159 °C (Phase I; Fig. 9). In their study, the salin-
ity  of  the  early  ore  forming  fluids  was  8—12 NaCl  equiv.
wt. %  in  sphalerite  and  15—19 NaCl  equiv.  wt. %  in  saddle
dolomite.  The  salinity  of  the  late  hydrothermal  phase  was
higher  as  indicated  by  the  data  from  fluorite  (18—21 NaCl
equiv.  wt. %).  A  similar  mixing  of  low-  and  high  salinity
fluids  during  ore  formation  in  the  Velence  Mts  was  first
suggested by Molnár (1996). Maintaining the concept of a
mixing  model  including  two  types  of  fluids  we  postulate
that fluid mixing may have played a significant role in ore
formation.

Fig. 8. Comparison of fluid inclusion data for
two Alpine-type epigenetic lead-zinc deposits in
the Drau Range (Bleiberg, Mežica; Kuhlemann et
al. 2001) and the Pb-Zn mineralization of the Ve-
lence Mts.

188

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Sources of Pb in the veins

The lead isotope ratios in the base-metal-fluorite

veins  of  the  Velence  Mts  and  the  Szabadbattyán
Block essentially overlap (Fig. 9a,b) with the data for
galena  from  Alpine-type  epigenetic  Pb-Zn  mineral-
izations along the PABL (Bleiberg, Mežica, Salafossa,
Raibl,  Gorno  (Figs. 1  and  11).  Köppel  &  Schroll
(1988)  proved  the  importance  of  early  Paleozoic
high-grade  metamorphic  crystalline  basement  rocks
(gneiss, amphibolite, micaschist) as sources of metals
in  the  Alpine-type  lead-zinc  deposits.  High-grade
metamorphic  rocks  are  not  known  in  the  currently
studied  areas,  but  pebbles  of  such  rocks  were  docu-
mented  in  a  late  Variscan  molass  formation,  located
close  to  the  reconstructed  pre-tectonic  site  (cf.  the
Carboniferous conglomerate in Fig. 10c).

It is therefore possible that the metals in the investi-

gated  deposits  of  the  Pannonian  Basin  were  also  de-
rived  from  a  range  of  rocks,  including  spatially
associated magmatic rocks (the host rock granite in the
Velence Mts and the andesite dykes at Szabadbattyán),
the underlying sedimentary rocks and the deeply situ-
ated metamorphic basement. Interestingly, despite the
difference in host rock character (Permian granite and
Devonian limestone, respectively), the ore lead signa-
tures  at  the  Velence  Mts  and  at  the  Szabadbattyán
Block are more or less identical (Fig. 9a,b). This sug-
gests  that  the  host  limestone  in  the  Szabadbattyán
Block did not act as a major source of lead, and it is
more likely that a range of deep-seated rocks provided
the metals.

Radiometric age constraints and age correlations
with adjoining areas

The age of the host granite in the Velence Mts is

280—290 Ma (Buda 1985) as is indicated by the K/Ar,
Rb—Sr data for rock-forming biotite. The K/Ar block-
ing temperature of pure illite is around 250 °C (Clauer
&  Chaudhuri  1995).  Hence,  it  seems  plausible  that
the measured K/Ar age data from pure illite from the
argillic  alteration  zones  around  the  base-metal-fluo-
rite veins of the Velence Mts represent the true age of
the  hydrothermal  circulation.  As  the  obtained  K/Ar

160 °C in Triassic times. Evidently, the inferred Triassic hy-
drothermal alteration was not related in age to the Carbonif-
erous,  magmatism  (host  granite),  Cretaceous  lamprophyre
dykes or to the Paleogene magmatic activity in the eastern-
most part of the Velence Mts. Therefore, we can rule out any
hypothesis  (Jantsky  1957;  Kaszanitky  1958;  Horváth  &
Ódor  1984)  assuming  that  either  of  these  magmatic  events
acted as the heat source for the mineralizing fluids.

Triassic magmatic activity in the Velence Mts is not known,

but age data for andesite dikes from the Szabadbattyán Block
(Balogh et al. 1983; Bagdaszarjan 1989; Dunkl 1991) are
equivalent to the obtained K/Ar ages for illite in the Velence
Mts. This is exemplified by a 210 ± 4 Ma K/Ar age of whole
rock samples of one andesite dyke from Szabadbattyán

Fig. 9. Lead isotope evolution diagrams (a –

207

Pb/

204

Pb—

206

Pb—

204

Pb,

b –

208

Pb/

204

Pb—

206

Pb/

204

Pb) with growth curves according to Zartman &

Doe (1981) (Z—D) and Stacey & Kramers (1975). The shaded boxes repre-
sent whole rock Pb isotope data of the three main tectonic units of the Alps
(Köppel & Schroll 1988). The field bordered by dashed line represents lead
isotope data from galena of Alpine-type Pb-Zn deposits along the PABL
(Köppel 1983). Data points represent lead isotope data from the Velence
Mts and the Szabadbattyán Block measured in galena and fluorite.

ages  of  210—230 Ma  almost  overlap  within  analytical  error,
it  is  possible  to  establish  a  Mid-Late  Triassic  ore-forming
event (Fig. 6). K/Ar data for the orthoclase from the western
part of the granite body at Velence Mts also provide support
for  a  Mid-Late  Triassic  thermal  event.  This  is  based  on  the
fact  that  the  blocking  temperature  of  K-feldspar  is  around
160 °C (Harrison et al. 1979), and therefore the K/Ar ages of
feldspars either represent the time of cooling of the rock be-
low  160 °C  (Faure  1977;  Richards  &  Noble  1998)  or  the
post-emplacement  history  involving  other  events  when  the
temperature of the rock passed the 160 °C isograd for the last
time.  Following  this,  we  anticipate  that  the  221 Ma  age  of
the  rock  forming  fresh  orthoclase  represents  a  re-set  age
which is due to a regional heating of the granite body above

189

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

(Bagdaszarjan 1989), whereas Balogh et al. (1983), obtained
213 ± 13 Ma  for  another  dyke.  Dunkl  (1991)  established  a
214 ± 5 Ma  age  for  titanite  from  those  andesite  dykes  by  the
fission track method (Fig. 6). This age agreement between the
two mineralized study areas suggests that a presently not iden-
tified  Triassic  magmatic  event  might  have  been  the  driving
force  for  hydrothermal  alteration  in  the  Velence  Mts.  This
view  is  consistent  with  an  active  Triassic  magmatism  along
the eastern segment of the PABL (Ferrara & Innocenti 1974).
There is evidence that it also extended into the Southern Alps.
The eastern part of the Neo-Tethys region is characterized by
slightly older magmatism (Haas 2004). Pamić (1984) reported
Ladinian  magmatic  ages  in  the  216—250 Ma  range  in  the
Karawanken,  by  using  a  range  of  isotopic  methods  (U—Pb,
Rb—Sr and K/Ar data), which may be related to the rift phase
of the Dinaric part of the Neo-Tethys Ocean. Castellarin et al.
(1988)  documented  Ladinian  bimodal  magmatites  from  the
Southern  Alps.  However,  on  the  basis  of  geochemical  data,
they emphasized an orogenic origin of the magmas.

It is not the aim of this paper to discuss whether the Ladin-

ian magmatic rocks in both the Alpine region and along the
PABL  have  a  rift  or  an  orogenic  origin.  Still,  as  a  general
theory (cf. Haas 2004), we prefer the rift origin and we con-
nect  the  Ladinian  hydrothermal  circulation  in  the  Velence
Mts  and  the  Szabadbattyán  region  to  the  contemporaneous
rift events in the Neo-Tethys Ocean.

Model of formation of lead-zinc deposits in the Pannonian
Basin and their possible genetic link to the Alpine-type epi-
genetic mineralizations

Comparison of the studied deposit and the Alpine deposits

is summarized in Table 5.

There are striking similarities between the granite-hosted

deposit  in  the  Velence  Mts  and  certain  deposits  (Meziča,
Bleiberg, Salafossa, Gorno, etc.) in the Alps along the PABL
(Fig. 10a,b,  Table 5),  especially  regarding  fluid  inclusion
and  lead  isotope  signatures.  However,  the  host  rock  of  the

Table 5: Comparison of geochemical, fluid inclusion and mineralogical characteristics of the studied (Szabadbattyán and Velence Mts) and
other base-metal and fluorite mineralizations along the PABL (Bolzao granodiorite, Alpine-type epigenetic lead-zinc mineralizations).

190

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Fig. 10.

–

Regional

geology

the

part

the

Alcapa

Megaunit

and

the

eastern

part

the

Eastern

and

Southern

Alps

after

Kázmér

Kovács

(1985).

The

Alcapa

Megaunit

escaped

during

the

Late

Paleogene—Early

Neogene

from

the

collision

zone

the

Eastern

Alps

and

Southern

Alps

along

the

dextral

PABL;

–

Pb-Zn

deposits

along

the

PABL

the

eastern

segment

the

Eastern

Alps

(Bauer

1985);

–

Pb—Zn

deposits

along

the

PABL

the

Pannonian

basin

(Sza

badbattyán

Block

and

Velence

Mts

after

Dudko

1999).

The

similar

geology

the

broader

vicinity

the

Pb—Zn

deposits

suggests

that

these

deposits

could

spa

tially

contact

prior

the

escape

the

Alcapa

Megaunit

the

Alpine

collision

zone.

191

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

Alpine-type  epigenetic  lead-zinc  deposits  in  the  Alps  is
mainly Triassic limestone (e.g. Raibl beds) and the ores oc-
cur as stratabound bodies, whereas mineralization in the Ve-
lence  Mts  is  characteristically  vein-type,  hosted  by  granite.
Mineralization in the Alpine deposits often occurs as matrix
of tectonic breccias, but also forms fissure filling, karst fill-
ing or fault-related epigenetic ore bodies (Brigo et al. 1977).
This  suggests  that  the  diagenetic  process  and  the  carbonate
host  rock  are  not  truly  decisive  factors  for  governing  ore
deposition,  and  mineralization  can  occur  in  very  different
forms and in different type of rocks.

Also, the timing aspect is important when a potential ge-

netic link is tested between different ores. Observations pre-
sented in this paper argue for an epigenetic, Mid-,
Late-Triassic ore-forming event in the Velence Mts and the
Szabadbattyán Block (209—232 Ma). Epigenetic lead-zinc
deposits north of the PABL occur in the Late—Triassic (Car-
nian – 228—216 Ma; Brigo et al. 1977).

Another candidate for comparison along the PABL is the

Brixen (Bolzano) granodiorite (Fig. 1), which is the host of
vein  type  quartz-fluorite  mineralization.  Age,  geochemical,
and genetic similarities of the two host crystalline formations
have  been  established  by  Buda  et  al.  (2004).  Age,  texture
and  fluid  inclusion  properties  of  the  two  mineralizations  in
the Velence Mts and in the Szabadbattyán Block also show
several  striking  similarities  (Table 5).  On  the  basis  of  the
characteristics  of  the  Bolzano  mineralization,  Hein  et  al.
(1990)  connected  the  formation  of  the  quartz-fluorite  veins
to a large-scale fluid flow system and excluded the possible
role  of  magmatism  as  a  driving  force  of  fluid  flow.  In  his
model,  fluorine  originated  from  the  sedimentary  basement

rocks.  Based  on  the  fluorine  anomalies  in  the  carbonate-
hosted lead-zinc deposits along the PABL, he proposed a ge-
netic  link  between  the  granite  hosted  quartz-fluorite  veins
and the lead-zinc deposits. Regarding the large distance be-
tween  Bolzano  granite  and  the  studied  deposits  ( ~ 600 km
along the PABL) it is not necessarily stated that the two crys-
talline  formations  formed  an  identical  unit.  However,  if  the
Velence  Mts  are  interpreted  as  a  tectonic  megamelange
along  the  PABL  the  former  spatial  relationship  of  the  two
rock units cannot be excluded.

In our model a rift related regional fluid flow was initiated

by the time of the Mid Triassic. The heat source of the fluid
convection  could  be  the  attenuated  and  heated  continental
crust  but  locally  magma  intrusions  may  also  have  played  a
significant role. Ca-rich, high-salinity formational fluids mi-
grating in the basement metamorphic and sedimentary rocks
leached  base  metals.  Mixing  with  low-salinity  fluids  and
cooling  decreased  their  transfer  capacity  and  base  metals
precipitated in some tectonic zones (Fig. 11). Consequently,
base-metal veins in the Velence Mts represent the relatively
deep channels of the fluid flow, whereas epigenetic deposits
in the Alps are the uppermost, discharge part of a similar hy-
drothermal system.

The spatial relationship between the different levels of the

hydrothermal convection system is not obvious at first sight.
However  several  authors  (Géczy  1984;  Dulai  1990;  Vörös
1993;  Csontos  1995;  Haas  et  al.  1995;  Ebner  et  al.  1998;
Márton  &  Fodor  2003)  proved  that  the  Transdanubian
Mountain Range escaped 450—500 km east from the Alpine
collision zone during the Late Paleogene—Early Neogene. Ac-
cordingly, in the Triassic, in its original position the Velence

Fig. 11. Proposed genetic model of lead-zinc mineralization in the Velence Mts and its possible connection to the Alpine-type epigenetic
lead-zinc mineralization, without scale. Base-metal-fluorite mineralization in the Velence Mts represents a deep conduit part of the hydro-
thermal system. During ascent and cooling of hydrothermal fluids, fissure filling and brecciated lead-zinc ore formed in Triassic limestones
along the PABL. Carbonate hosted Alpine-type epigenetic lead-zinc deposits formed at the discharge site of the convection system. Due to
the different tectonic histories during the Alpine orogeny epoch, shallow levels of the system are preserved in the Alps, whereas the deeper
part of the system is exposed in the central part of the Pannonian Basin.

192

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Mts  formed  the  basement  of  the  carbonaceous  sedimentary
formations  that  are  now  the  host  of  the  stratiform-stra-
tabound  epigenetic  deposits.  Due  to  the  intense  orogenic
processes during the Alpine orogeny in the Creatceous some
parts of the system were lifted up more intensively and eroded
(Velence  Mts,  Szabadbattyán  on  the  southern  flank  of  the
syncline of the Transdanubian Mountain Range) while other
parts were not exhumed and eroded (Alpine-type epigenetic
lead-zinc deposits).

Later, as a result of the eastward extrusion of the Alcapa

Megaunit from the Alpine collision zone, the two levels of
the former hydrothermal system were farther displaced.

Carbonaceous rocks similar to the host of the Alpine depos-

its far north from the PABL are widely known in the Trans-
danubian Mountain Range. Except for a few indications, no
mineralization has been found yet in these rocks. This implies
that the PABL as a major fluid flow channel had a particular
role in the formation of the various lead-zinc deposits.

Summary and conclusions

Clay mineralogy, K/Ar radiometric ages, lead isotope and

fluid inclusion studies have been carried out on the vein type
and metasomatic base-metal-fluorite mineralization of the
Paleozoic basement units of the Pannonian Basin in the Ve-
lence Mts and the Szabadbattyán Block in order to establish
a model for their origin.

The maximum temperature of the hydrothermal fluid

flow was around 250 °C according to the clay mineral stud-
ies. The fluids then gradually cooled during the hydrother-
mal fluid flow to below 200 °C. Formation of the
base-metal-fluorite mineralization is the result of the mixing
of low salinity (0—12 NaCl equiv. wt. %) and high salinity
(10—26 CaCl

equiv. wt. %) formational brines. Our studies

on  fluid  inclusions  and  clay  gangue  minerals  indicate  that
the  temperature  (130—240 °C)  and  pressure  conditions
(400—500 bar) during ore formation were different from the
magmatic—postmagmatic  system  for  the  Permian  granite
intrusion  (550—690 °C;  2 kbar)  and  the  Paleogene  fluid
flow (240—480 °C; 30—280 bars).

Lead isotope data (Velence Mts:

206

Pb/

204

Pb=18.278—18.363,

207

Pb/

204

Pb=15.622—15.690 and

208

Pb/

204

Pb = 38.439—38.587

and Szabadbattyán:

206

Pb/

204

Pb = 18.286—18.348,

207

Pb/

204

Pb = 15.667—15.736

and

208

Pb/

204

Pb=38.552—38.781)

demonstrate  a  common  isotope  pattern  for  the  two  studied
mineralizations  and  the  obtained  results  are  also  in  concor-
dance with data for Alpine-type epigenetic lead-zinc depos-
its.  Magmatic  rocks  and  basement  metamorphic  rocks,
carrying an upper crustal signature, probably supplied a ma-
jor part of the lead contained in the ores.

K/Ar radiometric age dating (208—232 Ma) suggests a

Mid- to Late-Triassic age of the mineralization and related
regional heating of the granite. Thus our results give no sup-
port to earlier hypotheses, including ore formation related to
Carboniferous, Cretaceous and Paleogene magmatism.

Several lines of presented evidence suggest a genetic rela-

tionship between the two studied mineralization of the Pan-
nonian Basin and other, Alpine-type epigenetic lead-zinc

deposits along the PABL, in the Southern and Eastern Alps.
A tectonic reconstruction suggests a direct spatial relationship
to  the  deposits  along  the  PABL  in  the  Southern  and  Eastern
Alps.  We  propose  that  the  two  described  mineralizations  in
the  Pannonian  basin  are  deep  feeder  channels  of  a  regional
fluid  flow  system  that  occasionally  discharged  to  form  shal-
low  epigenetic  Pb—Zn  mineralizations.  The  latter  are  now
eroded away, if they were ever present in the study areas.

Acknowledgments:  The  measurements  were  supported  by
the  Synthesys  (SE-TAF-3772)  program  of  the  EU.  The  au-
thors  are  particularly  grateful  to  the  editor  Pavel  Uher  and
the reviewers, Peter Koděra and Sándor Szakáll for their de-
tailed review of the manuscript. Their suggestions and con-
structive criticism of the earlier manuscript resulted in major
improvements to the final article.

References

Bagdaszarjan G.P. 1989: Radiometric age dates of samples from the

Velence Mts – Manuscript. Geol. Inst. Hung., Budapest.

Bajnóczi B. 2003: Palaeogene hydrothermal processes in the Ve-

lence Mountains, Hungary. Unpublished PhD Thesis, ELTE
University, Budapest, 1—116.

Bajnóczi B., Molnár F., Maeda K., Nagy G. & Vennemann T. 2002:

Mineralogy and genesis of primary alunites from epithermal
systems of Hungary. Acta Geol. Hung. 45, 1, 101—118.

Balogh K. 1985: Principles, application of the K-Ar age dating

method, and data interpretation. Mineral. Geochem. Rev.,
Budapest, 1—49.

Balogh K., Árva-Sós E. & Buda Gy. 1983: Chronology of granitoid

and metamorphic rocks of Transdanubia (Hungary). Ann. Inst.
Geol. Geofiz. 61, 259—364.

Bauer F.K. 1985: Geological Map of the Karawanken 1 : 25,000,

Westteil. Geol. Bundesanst., Wien.

Benedek K. 2002: Palaeogene igneous activity along the eastern-

most segment of the Periadriatic—Balaton Lineament. Acta.
Geol. Hung. 45, 4, 359—371.

Benedek K., Pécskay Z., Szabó Cs., Jósfai J. & Németh T. 2004:

Palaeogene igneous rocks in the Zala basin (Western Hungary):
Link to the Palaeogene magmatic activity along the Periadriatic
lineament. Geol. Carpathica 55, 1, 43—50.

Benkó Zs. 2008: Reconstruction of multi-phase fluid flow history

and tectonic evolution in a Variscan granite intrusion (Velence
Mts., Hungary). Unpublished PhD Thesis, ELTE University,
Budapest, 1—162.

Benkó Zs. & Molnár F. 2004: Application of studies on fluid inclu-

sion planes for evaluation of structural control on Variscan and
Alpine fluid mobilization processes in the monzogranite intru-
sion of the Velence Mts., (W-Hungary). Acta Mineral. Petrogr.,
Szeged 45, 1, 123—131.

Benkó Zs., Molnár F. & Lespinasse M. 2008: Application of studies

on fluid inclusion planes and fracture systems in reconstruc-
tion of fracturing history of granitoid rocks I.: introduction to
methods and implication for fluid-mobilization events in the
Velence Mts. Bull. Hung. Geol. Soc. 138, 3, 229—246.

Benkó Zs., Molnár F., Pécskay Z., Németh T. & Lespinasse M.

2012: The interplay of the Palaeogene magmatic-hydrohermal
fluid flow on a Variscan granite intrusion. age and formation
of the barite vein at Sukoró, Velence Mts, W-Hungary. Bull.
Hung. Geol. Soc. 142, 1, 45—58.

Bodnar R.J. 1993: Revised equation and table for determining the

193

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

TRIASSIC FLUID MOBILIZATION AND EPIGENETIC SULPHIDE MINERALIZATION (HUNGARY)

freezing point depression of H

O—NaCl solutions. Geochim.

Cosmochim. Acta 57, 683—684.

Brigo L., Kostelka L., Omenetto P., Schneider H.J., Schroll E.,

Schulz O. & Štrucl I. 1977: Comparative reflections on four
Alpine lead—zinc deposits. In: Klemm D.D. & Schneider H.J.
(Eds.): Time- and strata-bound ore deposits. Springer, Berlin,
273—294.

Broska I. & Uher P. 2000: Whole-rock chemistry and genetic ty-

pology of the West-Carpathian Variscan granites. Geol. Car-
pathica 52, 79—90.

Buda Gy. 1985: Origin of collision-type Variscan granitoids in

Hungary, West Carpathian and Central Bohemian Pluton. Un-
published PhD. Thesis, Budapest, 1—148.

Buda Gy. 1993: Enclaves and fayalite bearing pegmatitic “nests” in

the upper part of the granite intrusion of the Velence Mts,
W-Hungary. Geol. Carpathica 44, 3, 143—153.

Buda Gy., Koller F. & Ulrych J. 2004: Petrochemistry of Variscan

granitoids of Central Europe: Correlation of Variscan grani-
toids of the Tisia and Pelsonia terranes with granitoids of the
Moldanubicum, Western Carpathians and Southern Alps. A re-
view: part I. Acta Geol. Hung. 47, 2—3, 117—138.

Castellarin A., Lucchini F., Rossi P.L., Selli L. & Simboli G. 1988:

The Middle Triassic magmatic—tectonic arc development in the
Southern Alps. Tectonophysics 146, 79—89.

Clauer N. & Chaudhuri S. 1995: Clays in crustal environments.

Springer Verlag, Berlin, 1—369.

Cumming G.L. & Richards J.R. 1975: Ore lead isotope ratios in a con-

tinuously changing Earth. Earth Planet. Sci. Lett. 28, 155—171.

Csontos L. 1995: Tertiary tectonic evolution of the Intra-Carpathian

area: a review. Acta Vulcanol. 7, 1—13.

Csontos L. & Vörös A. 2004: Mesozoic plate tectonic reconstruc-

tion of the Carpathian region. Palaeogeogr. Palaeoclimatol.
Palaeoecol. 210, 1—56.

Csontos L., Nagymarosy A., Horváth F. & Kováč M. 1992: Ceno-

zoic evolution of the Intra-Carpathian area: a model. Tectono-
physics 208, 221—241.

Darida-Tichy M. 1987: Paleogene andesite volcanism and associated

rock alteration (Velence Mountains, Hungary). Geol. Carpathica
38, 1, 19—34.

DeIgnacio S.J., Munoz M., Sagredo J., Fernandes-Santin S. & Jo-

hansson Å. 2006: Isotope geochemistry and FOZO mantle com-
ponent of the alkaline—carbonatitic association of Fuerteventura,
Canary Islands, Spain. Chem. Geol. 232, 99—113.

Dudko A. 1999: Geological map of pre-Sarmatian surface of the

Balatonfő-Velence Area. In: Gyalog L. & Horváth I. 2004
(Eds.): Geology of the Velence Hills and the Balatonfő. Hung.
Geol. Inst. Budapest.

Dulai A. 1990: The Lower Sinemurian (Jurassic) brachiopod fauna

of the Lókút Hill (Bakony Mts., Hungary). Preliminary results.
Ann. Hist.—Natur. Mus. Nat. Hung. 82, 25—37.

Dunkl I. 1991: Fission track dating of tuffaceous Eocene Forma-

tions of the north Bakony Mountains (Transdanubia, Hungary).
Acta Geol. Hung. 33, 1—4, 13—30.

Dunkl I., Horváth I. & Józsa S. 2003: Andesite dykes and skarn for-

mations of the Szár Hill, Polgárdi, Hungary. Top. Miner.
Hung. 8, 55—86.

Ebner F., Kovács S. & Schönlaub H. 1998: Stratigraphic and facial

correlation of the Szendrő—Uppony Paleozoic (NE Hungary)
with the Carnic Alps-South Karawanken Mts. and Graz Palaeo-
zoic (Southern Alps and Central Eastern Alps), some paleogeo-
graphic implications. Acta Geol. Hung. 41, 4, 355—388.

Faure G. 1977: Principles of isotope geology. John Wiley & Sons,

New York, 1—458.

Ferrara G. & Innocenti F. 1974: Radiometric age evidences of a Tri-

assic thermal event in the Southern Alps. Geol. Rdsch. 63,
572—581.

Finger F., Broska I., Haunschmid B., Hraško ., Kohút M., Krenn

E., Petrík I., Riegler G. & Uher P. 2003: Electron-microprobe
dating of monazites from Western Carpathian basement grani-
toids: plutonic evidence for an important Permian rifting event
subsequent to Variscan crustal anatexis. Int. J. Earth Sci. 92,
86—98.

Fodor L., Jelen B., Márton E., Skaberne D., Car J. & Vrabec M.

1998: Miocene—Pliocene tectonic evolution of the Slovenian
Periadriatic fault: implications for Alpine-Carpathian extru-
sion models. Tectonics 17, 690—709.

Földvári A. 1952: Lead mineralization and fossiliferous limestone

outcrop at Szabadbattyán. MTA Tud. Oszt. Közl. 5, 1—2,
25—53.

Fülöp J. 1990: Geology of Hungary, Paleozoic. Hung. Geol. Inst.,

Budapest, 187—202.

Géczy B. 1984: Provincialism of Jurassic ammonites: examples

from Hungarian faunas. Acta Geol. Hung. 27, 3—4, 379—389.

Greene-Kelly R. 1953: The identification of montmorillonoids in

clays. J. Soil Sci. 4, 233—237.

Haas J. 2004: Geology of Hungary, Triassic. ELTE Eötvös Press,

Budapest, 35—74.

Haas J., Kovács S., Krystyn L. & Lein R. 1995: Significance of

Late—Permian Triassic zones in terrane reconstructions in the
Alpine—North Pannonian domain. Tectonophysics 242, 19—40.

Haas J., Mioc P., Pamić J., Tomljenović B., Árkai P., Bérczi-Makk

A., Koroknai B., Kovács S. & Felgenhauer E.R. 2000: Com-
plex structural pattern of the Alpine-Dinaridic-Pannonian tri-
ple junction. Int. J. Earth Sci. 89, 377—389.

Harrison T.M., Armstrong R.L., Naeser C.W. & Harakal J.E. 1979:

Geochronology and thermal history of the Coast Plutonic
Complex, near Prince Rupert, British Columbia. Canad. J.
Earth Sci. 16, 400—410.

Hedenquist J.W. & Lowenstern J.B. 1994: The role of magmas in the

formation of hydrothermal ore deposits. Nature 370, 519—527.

Hein U.F., Lüders P. & Dulski P. 1990: The fluorite mineralization

of the Southern Alps: combined application of fluid inclusions
and rare earth element (REE) distribution. Mineral. Mag. 54,
325—333.

Horváth I. & Ódor L. 1984: Alkaline ultrabasic rocks and associated

silicocarbonatites in the NE part of the Transdanubian Mts.,
Hungary. Miner. Slovaca 16, 115—119.

Jantsky B. 1957: Geology of the Velence Mts. Geol. Hung., Ser.

Geol. 10, 166.

Kaszanitzky F. 1958: Genetic relations of the Pátka—Kőrakás—hegy

ore occurrence, Velence Area, North Central Hungary. Ann.
Hist.—Natur. Mus. Nat. Hung. 50, 9, 19—30.

Kázmér M. & Kovács S. 1985: Permian—Palaeogene paleogeography

along the eastern part of the Insubric-Periadriatic Lineament
system: evidence for continental escape of the Bakony—Drauzug
Unit. Acta Geol. Hung. 28, 1—2, 617—648.

Kiss J. 1951: Hydrothermal mineralization on the northern part of

the Velence Mts. Bull. Hung. Geol. Inst. 1953, 111—127.

Kiss J. 2003: Geology and ore mineralization of the Szár Hill,

Polgárdi, Hungary. Top. Miner. Hung. 8, 29—54.

Kovács I., Szabó Cs., Bali E., Falus Gy., Benedek K. & Zajacz Z.

2007: Palaeogene—Early Miocene igneous rocks and geody-
namics of the Alpine—Carpathian Dinaric region: An integrated
approach. Geol. Soc. Amer., Spec. Pap. 418, 93—112.

Köppel V. 1983: Summary of lead isotope data from ore deposits of

the Eastern and Southern Alps: Some metallogenic and geotec-
tonic implications. In: Schneider H.J. (Ed.): Mineral deposits
of the Alpine Epoch in Europe. Springer, Berlin—Heidelberg,
162—269.

Köppel V. & Schroll E. 1988: Pb-isotope evidence for the origin of

lead in stratabound lead—zinc deposits in Triassic carbonates of
the Eastern and Southern Alps. Mineralium Depos. 23, 96—103.

Műsz.

194

BENKÓ, MOLNÁR, LESPINASSE, BILLSTRÖM, PÉCSKAY and NÉMETH

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2014, 65, 3, 177—194

Kuhlemann J., Vennemann T., Herlec U., Zeeh S. & Bechstädt T.

2001: Variations of sulfur isotopes, trace element composi-
tions, and cathodoluminesence of Mississippi Valley type
lead—zinc ores from the Drau—Range, Eastern Alps (Slovenia—
Austria): Implications for ore deposition on a regional versus
micro scale. Econ. Geol. 96, 1931—1941.

Lespinasse M. & Cathelineau M. 1990: Fluid percolation in a fault

zone: a study of fluid inclusion planes in the St. Sylvestre
granite, northwest Massiff Central, France. Tectonophysics
184, 173—187.

Lespinasse M. & Pecher A. 1986: Microfracturing and regional

stress field: a study of preferred orientations of fluid inclusion
planes in granite from the Massif Central, France. Struct. Geol.
8, 2, 169—180.

Lespinasse M., Désindes L., Fratczak P. & Petrov V. 2005: Mi-

crofissural mapping of natural cracks in rocks: Implications for
fluid transfers quantification in the crust. Chem. Geol. 223,
170—178.

Márton E. & Fodor L. 2003: Tertiary paleomagnetic results and

structural analysis from the Transdanubian Range (Hungary):
Rotational disintegration of the Alcapa Megaunit. Tectono-
physics 363, 201—224.

Molnár F. 1996: Fluid inclusion characteristics of Variscan and Al-

pine metallogeny of the Velence Mts., W-Hungary. In: Plate
tectonic aspects of the Alpine metallogeny in the Carpatho-
Balkan Region. Proceedings of the Annual Meeting Sofia 1996
2, 29—44.

Molnár F. 1997: Contribution to the genesis of molybdenite in the

Velence Mts.: mineralogical and fluid inclusion studies on the
mineralization of the Retezi audit. Bull. Hung. Geol. Soc. 127,
1—2, 1—17.

Molnár F. 2004: Characteristics of Variscan and Palaeogene fluid

mobilization and ore forming processes in the Velence Mts.,
Hungary: A comparative fluid inclusion study. Acta Mineral.
Petrogr. 45, 1, 55—63.

Molnár F., Török K. & Jones P. 1995: Crystallization conditions

of pegmatites from the Velence Mts., Western Hungary, on
the basis of thermobarometric studies. Acta Geol. Hung. 38,
1, 57—80.

Nemecz E. 1973: Clay minerals. Academic Press, Budapest, 1—507.
Oakes C.S., Bodnar R.J. & Simonson J.M. 1990: The system

NaCl—CaCl

—H

O: I. The ice liquidus at 1atm total pressure.

Geochim. Cosmochim. Acta 54, 603—610.

Pamić J.J. 1984: Triassic magmatism of the Dinarides in Yugoslavia.

Tectonophysics 109, 273—307.

Parry W.T. & Jasumback M. 2002: Clay mineralogy of phyllic and

intermediate argillic alteration at Bingham, Utah. Econ. Geol.
97, 221—239.

Reyes A.G. 1990: Petrology of Philippine geothermal systems and

the application of alteration mineralogy to their assessment.
J. Volcanol. Geotherm. Res. 43, 279—309.

Richards J.P. & Noble S.R. 1998: Application of radiogenic isotope

systems to the timing and origin of hydrothermal processes.
Rev. Econ. Geol. 9—10, 199—233.

Scroll E. & Pak E. 1983: Sulfur isotope investigations of ore mineral-

izations of the Eastern Alps. In: Schneider J.H. (Ed.): Mineral
deposits of the Alps and of the Alpine Epoch in Europe.
Springer, Berlin, Heidelberg, 169—175.

Schuster R., Scharbert S. & Abart R. 1999: Permo-Triassic crustal

extension during opening of the Neotethyan-ocean in the Aus-
troalpine—South Alpine realm. Tüb. Geowiss. Arb. 52, 5—6.

Stacey J.S. & Kramers J.D. 1975: Approximation of terrestrial lead

isotope evolution by a two-stage model. Earth. Planet. Sci. Lett.
26, 207—221.

Szakáll S. & Molnár F. 2003: Primary and secondary minerals of

the Szabadbattyán ore deposit (W-Hungary). In: Szakáll S. &
Fehér B. (Eds.): Minerals of the Szár Hill Polgárdi, Hungary.
Herman Ottó Museum, Miskolc, 145—175.

Środoń J. 1984: X-ray powder diffraction identification of illitic

materials. Clays and Clay Miner. 32, 5, 337—349.

Tari G. 1996: Neoalpine tectonics of the Danube Basin (NW Pan-

nonian Basin, Hungary). In: Ziegler P.A. & Horváth F. (Eds.):
Peri-Thetys Memoir 2: Structure and prospects of Alpine ba-
sins and forelands. Mem. Mus. Nat. Hist. Natur. 170, 439—454.

Uher P. & Broska I. 1994: The Velence Mts. granitic rocks:

geochemistry, mineralogy and comparison to Variscan West-
ern Carpathian granitoids. Acta Geol. Hung. 37, 45—66.

Uher P. & Broska I. 1996: Post-orogenic Permian granitic rocks in

the Western Carpathian-Pannonian area: Geochemistry, miner-
alogy and evolution. Geol. Carpathica 47, 311—321.

von Blanckenburg F. & Davies J.H. 1995: Slab breakoff: a model

for syncollisional magmatism and tectonics in the Alps. Tec-
tonics 14, 1, 120—131.

Vörös A. 1993: Jurassic microplate movements and brachiopod mi-

grations in the western part of the Tethys. Palaeogeogr. Palaeo-
climatol. Palaeoecol. 100, 125—145.

Zartman R.E. & Doe B.R. 1981: Plumbotectonics – The model.

Tectonophysics 75, 135—162.

Zeeh S., Kuhlemann J. & Bechstädt T. 1998: The classical lead—

zinc deposits of the eastern Alps (Austria/Slovenia) revisited:
MVT deposits resulting from gravity driven fluid flow in the
Alpine realm. Geologija 41, 257—273.

Zhang Y.G. & Frantz J.D. 1987: Determination of the homogeni-

zation temperatures and supercritical fluids in the system
NaCl—KCl—CaCl

—H

O using synthetic fluid inclusions. Chem.

Geol. 64, 335—350.

Zhao M.W., Ahrendt H. & Wemmer K. 1997: K-Ar systematics of

illite/smectite in argilliceous rocks from the Ordos basin, China.
Chem. Geol. 136, 153—169.

Zwingmann H., Mancktelow N., Antognini M. & Lucchini R. 2010:

Dating of shallow faults: New constraints from the AlpTransit
tunnel site (Switzerland). Geology 38, 487—490.

ELECTRONIC SUPPLEMENT — BENKÓ et al.: TRIASSIC FLUID MOBILIZATION AND EPIGENETIC LEAD-ZINC SULPHIDE
MINERALIZATION IN THE TRANSDANUBIAN SHEAR ZONE (PANNONIAN BASIN, HUNGARY)

Appendix A

Fluid inclusion data. A — Low salinity fluid inclusions modelled in the NaCl+H

O binary system.

Block

Locality

Host

mineral

Host rock
alteration

Fluid inclusion

classifiacation

Th (°C)

Te (°C)

Tm (°C)

Salinity

(CaCl

equiv. wt. %)

Secondary

192

–48

–15.8

18.3

Secondary

199

–47

–16.0

18.4

Secondary

243

Secondary

246

–47

–16.0

18.4

Secondary

214

–48

–16.0

18.4

Secondary

226

–16.8

18.9

Secondary

213

–15.6

18.2

Secondary

239

–15.6

18.2

Secondary

228

–8.8

13.2

Secondary

229

Secondary

226

Secondary

218

–13.0

16.5

Secondary

212

–48

–14.0

17.2

Secondary

235

Secondary

185

–10.4

14.5

Secondary

229

–15.0

17.8

Secondary

204

Secondary

142

–50.2

–11.4

15.3

Secondary

–48

–16.0

18.4

Secondary

200

–17.0

19.0

Secondary

151

–41

–12.8

16.4

Secondary

120

–45

–20.3

20.8

Secondary

151

–51

–19.8

20.6

Secondary

170

–51

–11.1

15.1

Secondary

144

–15.6

18.2

Secondary

138

–50

–25.0

23.1

Secondary

–45

–31.0

25.5

Secondary

157

–57

–33.0

26.2

Secondary

160

–60

–28.0

24.3

Secondary

205

–15.1

17.9

Secondary

128

–56.6

–17.4

19.3

Secondary

167

–56

–20.0

20.7

Secondary

167

–56.6

–23.3

22.3

Secondary

191

–53

–18.0

19.6

Secondary

184

–55

–21.4

21.4

Secondary

214

–57.2

–22.2

21.8

Secondary

164

–51

–19.0

20.2

Secondary

197

–57

–17.5

19.3

Secondary

217

–53.7

–18.1

19.7

Secondary

203

–18.3

19.8

Secondary

211

–52

–17.6

19.4

Secondary

137

–64.5

–28.4

24.5

Secondary

200

–64

–28.1

24.4

Secondary

155

–66

–20.6

21.0

Secondary

158

–17.8

19.5

Secondary

–66

–17.4

19.3

Secondary

157

–57

–17.0

19.0

Secondary

–58.8

–16.9

19.0

Secondary

133

–27

–16.6

18.8

Secondary

159

–60

–15.2

18.0

Secondary

103

–65

–14.9

17.8

Secondary

162

–65

–14.0

17.2

Secondary

146

–57

–13.3

16.7

Secondary

140

Secondary

157

Secondary

152

Secondary

172

ér

-k

Secondary

196

ELECTRONIC SUPPLEMENT — BENKÓ et al.: TRIASSIC FLUID MOBILIZATION AND EPIGENETIC LEAD-ZINC SULPHIDE
MINERALIZATION IN THE TRANSDANUBIAN SHEAR ZONE (PANNONIAN BASIN, HUNGARY)

Appendix B

Fluid inclusion data. B — High salinity fluid inclusions modeled in the CaCl

O binary system.

Block

Locality

Host

mineral

Host rock
alteration

Fluid inclusion

classifiacation

Th (°C)

Te (°C)

Tm (°C)

Salinity

(CaCl

equiv. wt. %)

Secondary

113

Secondary

139

–51.2

–22.7

22.0

Secondary

163

–21.7

21.5

Secondary

166

–29.0

24.7

Secondary

134

–28.7

24.6

Secondary

112

Secondary

113

Secondary

116

Secondary

108

Secondary

139

Secondary

134

Secondary

103

–20.9

21.1

Secondary

113

–16.9

19.0

Secondary

–23.0

22.2

Secondary

118

–20.2

20.8

Secondary

–14.9

17.8

Secondary

114

Secondary

135

–9.4

13.7

Secondary

118

–8.7

13.1

Secondary

150

–21.9

21.6

Secondary

119

–16.0

18.4

Secondary

134

0.0

Secondary

132

–16.0

18.4

Secondary

–15.0

17.8

Secondary

101

–14.0

17.2

Secondary

–33

–25.0

23.1

Secondary

115

–10.4

14.5

Secondary

119

–23.7

22.5

Secondary

123

–50

–26.5

23.7

Secondary

119

–48

–27.0

23.9

Secondary

–48

Secondary

–15.0

17.8

Secondary

–47.6

–10.5

14.6

Secondary

–57

–30.5

25.3

Secondary

–56.1

–25.0

23.1

Secondary

133

–14.0

17.2

Secondary

137

Secondary

118

–13.0

16.5

Secondary

–24.5

22.9

zé

ér

Secondary

–20.2

20.8

Secondary

289

–16.0

18.4

Secondary

296

–5.8

10.0

Secondary

282

–16.5

18.7

Secondary

–13.9

17.12

Secondary

113

Secondary

116

–47

–13.0

16.5

Secondary

–14.7

17.64

Primary

105

–53.6

–17.0

19.03

Primary

105

–53.1

–16.9

18.97

Primary

112

Primary

109

–53

–16.7

18.86

Primary

106

–50.7

–17.3

19.2

Primary

109

–50.4

–15.8

18.32

Primary

–50.2

–16.8

18.92

Primary

–56.6

–20.9

21.14

Primary

–48.6

–19.0

20.15

Primary

–48.7

–22.1

21.73

Primary

–49.5

–20.8

21.09

Primary

–51.7

–18.8

20.04

Primary

–57.5

–17.0

19.03

Primary

–55.1

–23.0

22.16

Primary

–54

–16.4

18.68

Secondary

138

–70

–24.7

22.94

Secondary

159

–67

–25.4

23.23

Secondary

204

–67

–26.0

23.51

Primary

–20

–19.0

20.15

Primary

–25.0

23.08

Primary

–19.8

20.57

Secondary

121

–23.2

22.26

Secondary

175

–69

–26.7

23.81

Secondary

166

–72

–24.6

22.9

Primary

183

–78.5

–24.6

22.9

Primary

–50.6

–16.1

18.5

Primary

–56

–14.9

17.76

Primary

–61.8

–15.7

18.26

Primary

139

Primary

126

Primary

–51

Primary

–14.0

17.18

Primary

–17.0

19.03

-k

Primary

–13.7

16.98