Occurrence of Apatite Associated With Magnetite in an Ophiolite Complex (Othrys), Greece

7/30/2019 Occurrence of Apatite Associated With Magnetite in an Ophiolite Complex (Othrys), Greece

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American Mineralogist, Volume 86, pages 11431150, 2001

0003-004X/01/00101143$05.00 1143

INTRODUCTION

Segregations of apatite in association with Fe-Ti oxides

occur in a variety of geological settings. Nelsonites are rare

igneous rocks composed largely of apatite and Fe-Ti oxides

(magnetite, ilmenite, or rutile) that occur in association with

anorthosite suite rocks (Philpotts 1967, 1981; Watson and Green

1981; Kolker 1982; Herz and Force, 1987; Force 1991; Ashwal

1993; Owens and Dymek 1992; Darling and Florence 1995;

Duchesne 1999). Nelsonite is thought by some to originate as

an immiscible liquid separated from parent magmas of

ferrodioritic composition (Philpotts 1967, 1981; Kolker 1982).

Another kind of association of magnetite and apatite, withoutsignificant ilmenite or rutile, is found in alkaline or calc-alka-

line igneous rocks (McKeown and Klemic 1956; Philpotts 1967;

Darling and Florence 1995). The origin of apatite-magnetite

associations in these types of igneous rocks is not clear. Both a

magmatic (Park 1961; Henriquez and Martin 1978; Naslund et

al. 1998) and hydrothermal origin (Barton and Johnson 1996;

Murray and Oreskes 1997; Barton 1998) have been proposed

for the El Laco deposit, Chile. The characteristics of the Kiruna

deposit, in Northern Sweden, are not definitive regarding its

origin. On the basis of field, textural, mineralogical, and

geochemical data, an exhalative-sedimentary origin has been

proposed by Park (1975) for the Kiruna deposits. Recently, the

Kiruna deposit has been compared to the El Laco deposit in

the Chilean Andes (Nystrom and Henriquez 1994).

Low-Ti, Fe-oxide (Cu-U-Au-Ag REE) deposits, like the

giant Olympic Dam (Australia), Bayan Obo (China), and most

of the New York-New Jersey deposits, are characterized by

magnetite and/or hematite and most contain apatite with sig-

nificant amounts of REE. These deposits exhibit features con-

sistent with a hydrothermal origin (Hitzman et al. 1992; Foose

and McLelland 1995; Barton and Johnson 1996; Oreskes and

Hitzman 1997).Occurrences of apatite in ultramafic rocks are very rare

(Mitchell et al. 1943; Southwick 1968; Honnorez and Kirst

1975; Nickel et al. 1979; Hopkinson and Roberts 1995; Gjata

et al. 1995; Dick and Natland 1999). Recently, small concen-

trations of apatite associated with magnetite or silicates were

discovered along a shear zone in the Othrys (Ano Agoriani area)

ophiolite complex, Greece, at the tectonic contact between a

gabbroic rock and serpentinized lherzolite. This paper is prob-

ably the first report of an apatite-Fe oxide association in an

ophiolite complex, and we provide a description of the apatite-

magnetite occurrence, an account of its mineral chemistry, and

a discussion of its genesis.* E-mail: [email protected]

Occurrence of apatite associated with magnetite in an ophiolite complex (Othrys), Greece

IOANNIS MITSISAND MARIA ECONOMOU-ELIOPOULOS*

University of Athens, Department of Geology, Panepistimiopolis, Athens 15784

ABSTRACT

Small irregular to lens-like occurrences (maximum 0.5 1 m) of apatite associated with magne-

tite and silicates are present in the Agoriani area of the Othrys ophiolite complex, central Greece.

The Ano Agoriani area is dominated by peridotite (plagioclase lherzolite) of the mantle sequence,

intruded by irregular bodies, dikes, and veins of gabbro, as well as by dikes of pyroxenite and peg-

matitic gabbro.

Apatite occurs as large (up to 3 cm long) well-formed crystals associated with magnetite. The

aggregates consist predominantly of apatite, or massive magnetite with subordinate amounts of apa-

tite. Apatite may also be accompanied by silicate minerals, mainly chlorite and lesser amounts of

serpentine, tremolite, and Ni-silicates (nepouite, pimelite), and by Ni-sulfides (pentlandite, violarite,

heazlewoodite).

The apatite-magnetite association from the Agoriani area differs from nelsonite hosted by an-

orthosite suites with respect to: (1) the host rock type (ophiolites); (2) the highly variable proportion

between apatite-magnetite; (3) the large size (up to 3 cm) of the apatite crystals; (4) the lack of

fluorine (


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MITSIS AND ECONOMOU-ELIOPOULOS: APATITE-MAGNETITE ROCK1144

CHARACTERISTICFEATURESOFTHEOTHRYSCOMPLEX

The Mesozoic Othrys ophiolite complex consists of a stack

of thrust sheets in which overlapping stratigraphic successions,

consisting mainly of harzburgites, lherzolites, gabbros, mafic

dikes, and pillow lavas, have been recognized (Hynes 1972;

Nisbet 1974; Menzies 1974; Konstantopoulou and Rassios

1993). The presence of both lherzolite and harzburgite in the

mantle sequence of the complex, and the variable geochemical

affinities of the lavas, provide evidence for development of the

complex during more than one oceanic stage, involving MORB

and supra-subduction zone (SSZ) features that may be inter-

preted as related to a back-arc basin (Hynes 1972; Nisbet 1974;

Smith et al. 1975; Sovatsoglou-Skounakis 1982; Paraskevo-

poulos and Economou 1986; Economou-Eliopoulos and

Paraskevopulos 1997).

Two tectonically separate chromite deposits, Eretria and

Domokos, have been exploited for refractory-grade chromite

resources (about 3 million tons). Small bodies of sulfide min-

erals (pyrrhotite, chalcopyrite, and minor pentlandite), are also

found at the Eretria mine, whereas magnetite occurs at the pe-riphery of a few podiform bodies (Economou and Naldrett

1984). Both high-temperature deformation (characterized by

mylonite zones and mineral foliations) and low-temperature

brittle deformation have been superimposed onto primary

mantle fabrics, and onto magmatic textures of rocks and ores

(Konstantopoulou and Rassios 1993).

DESCRIPTIONOFTHEAPATITE-MAGNETITEOCCURRENCE

The Ano Agoriani area (8 km west of Domokos), in the

western part of the Othrys complex, is dominated by plagio-

clase lherzolite (Fig. 1) consisting of forsterite, enstatite, diop-

side, and plagioclase, with minor spinel. Irregularly shapedbodies of gabbro and gabbroic dikes or veins intrude the pla-

gioclase lherzolite of the mantle sequence. Pyroxenite and gab-

bro pegmatitic dikes containing 220 cm pyroxene crystals also

cut lherzolite (Nisbet 1974; Menzies 1974). Apart from the

gabbro units of the magmatic sequence, numerous small gab-

broic bodies are found within the serpentinized lherzolite. An

abundance of gabbroic pods and dikes within plagioclase

lherzolite is considered to be characteristic of sections near the

petrological Moho (Menzies 1973, 1974; Nicolas 1989). These

gabbroic bodies are composed mainly of randonly oriented

skeletal plagioclase in a matrix of clinopyroxene (diopside-

augite). Small amounts of chlorite and spinel are also present.

These gabbroic bodies appear undeformed in contrast to the

ductile-brittle deformation along thrust surfaces at the tectonic

contact between gabbroic rocks and serpentinized lherzolite.

Variable proportions of apatite in association with magne-

tite were discovered in the Ano Agoriani area along a shear

zone, at the contact between lherzolite and a relatively large

(50 250 m), fine-grained body of gabbro (Fig. 1).

METHODSOFINVESTIGATION

The apatite-magnetite association from the Ano Agoriani

area was investigated as follows. X-ray powder diffraction pat-

terns (XRD) of apatite were obtained with a Siemens D5005

X-ray diffractometer at the University of Athens. Major- and

trace-element compositions, including rare earth elements

(REE) were determined on bulk mineral separates by a combi-

nation of instrumental neutron activation analysis (INAA), and

colorimetric methods at the XRAL Laboratories, Ontario,

Canada. Thin sections were investigated by optical microscopy

and scanning electron microscopy. Mineral compositions were

determined by electron microprobe analysis at the University

of Athens, Department of Geology, using a CambridgeMicroscan-5 instrument and a JEOL JSM 5600 scanning elec-

tron microscope, both equipped with automated energy disper-

sive analysis system, LINK 2000 and ISIS 300 OXFORD,

respectively. The H2O content of apatite was determined by

the Penfield method (Mitchell et al. 1943). Thermogravimetric

(TG) analysis of apatite was performed with a Perkin Elmer

TGS-2 thermal analyzer using a 5.0 deg/m in heating and ni-

trogen atmosphere, in the temperature range 80950 C.

MINERALOGY

Small, irregular to lens-shaped (maximum 0.5 m 1 m)

apatite-magnetite occurrences are composed of large euhedral

apatite crystals, ranging from a few millimeters to 3 cm in

length, in a magnetite matrix (Fig. 2). The color of apatite is

whitish, and it occurs mainly within massive magnetite or,

where associated with silicates (magnetite), it occurs either

as undeformed or fragmented to rounded crystals. Proportions

of apatite to magnetite are highly variable (Fig. 2). Inclusions

of magnetite within apatite, and Ni-sulfides (mainly pentland-

ite) dispersed throughout both apatite and magnetite are com-

mon, suggesting that all these minerals crystallized at the same

time.

In some cases, apatite is accompanied only by silicate min-

erals, mainly chlorite that may be Ni-bearing, and lesser

amounts of serpentine, tremolite, Ni-silicates (nepouite,pimelite), and Ni-sulfides (pentlandite, violarite,

heazlewoodite). Moreover, chlorite is a common mineral along

cracks and around the periphery of most apatite crystals, either

associated with magnetite or silicates. Goethite is a common

alteration product of magnetite.

Most apatite grains contain abundant fluid inclusions. They

appear to be primary on a textural basis (Roedder 1984), and

consist of very small, two-phase inclusions, containing aque-

ous liquid (L > 50%) and a vapor phase (Fig. 3).

The investigation of apatite with the scanning electron mi-

croscope and the microprobe revealed no zoning, very low REE

contents (below the detection limit of the method), and inclu-

sions of monazite crystals (Fig. 4).

MINERALCOMPOSITIONS

The large size of the apatite and magnetite crystals allowed

for both bulk and electron microprobe analysis. The H2O con-

tent in apatite ranges from 1.1 to 1.9 wt% and Cl from 6300 to

7500 ppm, whereas F is less than 20 ppm (Table 1). The pres-

ence of many small fluid inclusions, containing aqueous fluids

as the main phase, indicates that bulk H2O contents do not re-

flect only the (OH) anions in the apatite. Nevertheless, the pre-

dominant anions are (OH) and Cl, corresponding to

chlor-hydroxyl-apatite, consistent with the XRD pattern.

The minor and trace element contents of apatite (Table 1)


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MITSIS AND ECONOMOU-ELIOPOULOS: APATITE-MAGNETITE ROCK 1145

are consistent with the presence of chlorite and Ni-silicates

along cracks in the apatite, and with the presence of magnetite

and Ni-sulfides (mainly pentlandite) inclusions. The rare-earth

element (REE) content in the Agoriani apatite is relatively high

(up to 1350 ppm REE). In addition, the apatite displays steeply

fractionated chondrite-normalized patterns (Fig. 5) with veryhigh La/Lu ratios (average 1570).

Magnetite is pure, with very little Al, Mg, Ni, and Ti. Bulk

samples, however, have high Ni because of the presence of Ni-

sulfide inclusions (Table 1). The REE content of the Ano

Agoriani magnetite is below the detection limit of the INAA

method (for example


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Alkaline or calc-alkaline rocks

The origin of apatite-magnetite associations in alkaline orcalc-alkaline igneous rocks is not clear. For example, the El

Laco deposit, Chile, situated on the flanks of an andesite-

rhyodacite volcano, consists of five massive magnetite-hema-

tite bodies surrounded by numerous dikes and veins of

intergrown magmatic pyroxene and apatite. Some researchers

favor a magmatic origin (Park 1961; Henriquez and Martin

1978; Hitzman et al. 1992; Naslund et al. 1998) and others a

hydrothermal origin (Barton and Johnson 1996; Barton, 1998).

The Kiruna deposit, Northern Sweden, constitutes the great-

est concentration of apatite-iron ore in the world. As with the

El Laco deposit, it is considered to be magmatic in origin by

some investigators (Frietsch 1978) but hydrothermal by others

FIGURE 2. Large and well-formed apatite crystals (white) in magnetite (black). In the right specimen, the lower area (gray) is chlorite and

serpentine. (Scale bar = 9 cm.)

FIGURE 3. Small two-phase liquid-rich inclusions in apatite. Transmitted light.

(Barton and Johnson 1996; Barton 1998). On the basis of field,

textural, and mineralogical data, Parak (1975) proposed thatthe Kiruna deposits were exhalative-sedimentary in origin. It

is remarkable that within banded ores, small monazite needles

occur as inclusions in individual apatite crystals (Parak 1975).

Recently, the features of Kiruna have been compared with

those of El Laco and it has been suggested that such magmatic

ores, occurring in rocks ranging from Proterozoic to Cenozoic,

are not unique (Nystrom and Henriquez 1994). For example,

the deposits of the Cerro de Mercado, Durango, Mexico, are

considered to have formed as a result of a variety of subaerial

volcanic processes. During the later stages of the cooling pro-

cess, a quartz latite dike intruded the deposit, while a volatile-

rich, iron-oxide-rich phase is suggested to have evolved from


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tite-actinolite veins, breccias, and wall-rock replacement, and

an outer zone of disseminated sulfides. It was concluded that

high temperature, low initial water content, and shallow-level

emplacement by intermediate plutons are necessary for the

development of Kiruna-type deposits (Hildebrand 1986).

Mafic-ultramafic rocks

Layered mafic intrusions. Apatite-enriched layers have

been reported in the Upper Zone of the Bushveld complex.

Textural and compositional relations suggest that the periodic

development of an immiscible Fe-Ti-Ca-P liquid in the top-most 1000 m of the Upper Zone (Von Gruenwaldt 1994). The

development of the mineralized zones at the base of distinct

geochemical cycles suggests the formation of the immiscible

Fe-Ti oxide and apatite by magma mixing processes (Von

Gruenewaldt 1994).Also, in the Bushveld complex, with the

exception of its abundant fluorite, the Vergenoeg deposit is re-

lated to granites containing fayalite, fluorite, apatite, ilmenite,

and magnetite, and is similar to massive iron deposits as Kiruna

and Cerro Mercado (Borrok at al. 1998). Furthemore, based on

isotope and fluid inclusion data on fluorite from the Vergenoeg

deposit which contain abundant aqueous inclusions, Borrok et

al. (1998) concluded that this mineralization formed from hy-

drothermal fluids of magmatic origin.Ultramafic chlorite rocks. Well-documented occurrences

of fluor-hydroxyl-apatite have been found in Georgia and Mary-

land of the U.S.A., associated with chlorite-talc schists located

in the peripheral parts of small ultramafic bodies (Mitchell et

al. 1943; Southwick 1968; Herz and Valentine 1970). More

specifically, a small body of ultramafic chlorite rock contain-

ing unusually large quantities of rutile, magnetite, apatite, and

ilmenite is present in Harford County, Maryland. The central

part of the ultramafic body is mostly massive to schistose soap-

stone and serpentinite, whereas its southwest margin contains

lenses of strongly deformed uralitized gabbro and pyroxenite.

Mitchell et al. (1943) and Southwick (1968) concluded that

FIGURE 4. Small crystals of monazite included within apatite.

Backscattered and secondary electron micrograph. (Scale bar = 5 m.)

FIGURE 5. Chondrite-normalized REE-patterns for apatites. Datafrom Table 1, chondritic values after Taylor and McLennan (1985).

the parent magma (Lyons 1988).

In NW Canada, magnetite-apatite-actinolite rocks are asso-

ciated with plutons that intrude andesites of an early Protero-

zoic continental magmatic arc. These plutons exhibit wide

alteration halos comprising an inner zone of nearly complete

wall-rock albitization, an intermediate zone of magnetite-apa-

TABLE 1. Average (n = 3) chemical composition of apatite and mag-

netite from the Agoriani area, Othrysapati te associated with: magnet ite associated

Mineral silicates & silicates magnetite with apatitesamples magneti te

AP-PEG 6-MG2 7-A 7-5Mt 7-Mt(593)

wt%CaO 53 50 54.2 0.32 0.98P2O5 39.2 38.5 43.1


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the hydroxyl-apatite in these rocks was initially normal fluor-

apatite, and that exchange of (OH) for F-anions took place dur-

ing low-grade metamorphism and associated black-wall

metasomatism in the presence of excess water.

Within serpentinized peridotite near Nullagine, Western

Australia, Ni mineralization associated with lesser amounts of

magnetite, apatite, and chlorite occurs along shear zones, and

has been attributed to hydrothermal and/or metasomatic activ-ity (Nickel et al. 1979).

Ophiolite complexes. Apatite has been reported in Fe-Ti

oxide-rich gabbro localized along shear zones in the Lizard

complex, U.K. (Hopkinson and Roberts 1995), and in core

samples from hole 735b at the Atlantis II Fracture zone, South-

west Indian Ridge (Dick and Natland 1999). In layer 3, Fe-Ti

oxide-rich gabbro of the Lizard ophiolite, ilmenite and magne-

tite (in a ratio of 12:1) poikilitically enclose zircon and apatite.

The origin of this association is attributed to the migration and

impregnation of evolved Fe, Ti-rich melts in deformed areas

(including shear zones) of gabbro (Hopkinson and Roberts

1995). Subordinate quantities of apatite are found in veins com-

posed mainly of zoisite, actinolite, and euhedral chlorite, which

are related to hydrothermal brecciation in and adjacent to shear

zone.

In rocks collected from the Atlantis II Fracture zone, South-

west Indian Ridge, Dick and Natland (1999) described large

euhedral crystals of apatite contained in ilmenite-magnetite

patches. These Fe-Ti oxides (which locally include Fe-Cu-Ni

sulfides) are abundant in the most-deformed (sheared and brec-

ciated) gabbro and least-abundant in the least-deformed rocks.

In most cases, the oxides occur as an undeformed coarse ma-

trix in shear zones, postdating the major phase of deformation.

However, in a few cases, the oxides predate the deformation.

Small patches of late felsic material contain mainly amphib-ole, ilmenite, and magnetite, with minor amounts of sulfides,

quartz, apatite, and zircon, suggesting that the Fe-Ti oxides

precipitated from highly evolved melts and/or late-magmatic

hydrous fluids.

In the Puka ophiolite massif, Albania, occurrences of dis-

seminated apatite in Fe-Ti oxide rich gabbro also have been

reported but no interpretation was offered (Gjata et al. 1995).

Low-Ti oxide-apatite

A distinct class of mineral deposit has been recognized re-

cently that are characterized by low-Ti Fe ores containing vari-

able amounts of Cu, U, Au, and REE, like the deposits of

Missouri and Kiruna of Sweden, the giant Olympic Dam ofAustralia, the giant Bayan Obo of China, the Humboldt of Ne-

vada, the New York and New Jersey (Oreskes and Einaudi 1990;

Hitzman et al. 1992; Foose and McLelland 1995). All these

deposits are characterized by magnetite and/or hematite ores

with low Ti content (


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tite crystals within pillow lavas, which have been strongly af-

fected by hydrothermal alteration (Economou-Eliopoulos,

unpub. data), may indicate that the apatite was initially F-rich

and that a gradual exchange of (OH) for F has occurred. How-

ever, the large size (up to 3 cm) of the apatite crystals and their

spatial association with shear zonesseems to be consistent with

its deposition into preexisting lithologies rather than being the

product of a replacement process. The dominance of (OH) ions

in the studied apatite, and the presence of abundant primary,

liquid-rich, two-phase fluid inclusions (Fig. 3) suggests that

apatite formed in the presence of an aqueous fluid phase.

Deposition of apatite and the associated minerals are re-

lated to the circulation of an oceanic hydrothermal system, prob-ably a Cl-rich brine, as is exemplified by the presence of

Cl-apatite. The presence of inclusions of magnetite within apa-

tite and the association of sulfides with both apatite and mag-

netite suggest that these minerals share a common origin. As

far as the origin of the association of massive magnetite with

sulfides of both Cyprus and Fe-Cu-Ni-Co type in ophiolite com-

plexes elsewhere, it has been suggested that they too have pre-

cipitated from circulating hydrothermal systems. Interaction

of the hydrothermal system with the host rocks produces a re-

duced, slightly acidic, saline solution, which can be assumed

to rise preferentially along a zone of high permeability. Physi-

cochemical changes (temperature, redox, pH conditions) within

the hydrothermal system at near-surface or at lower stratigraphiclevels like that of the gabbros, cause precipitation of sulfide-

oxide mineralization (Economou and Naldrett 1984; Foose et

al. 1985; Scott et al. 1990; Eliopoulos et al. 1998).

Recently, on the basis of fluid inclusion data, replacement

textures, extensive zones of wall-rock Fe metasomatism,

geochemical data (isotopic, major- and trace- element compo-

sitions) and the presence of Cl-apatite, the hydrothermal origin

has been suggested for another class of low-Ti iron-oxide de-

posits (Cu-U-Au-REE), like those deposits in Missouri, Kiruna

in Sweden, Olympic Dam in Australia, the Bayan Obo in China,

and Humboldt in Nevada (Oreskes and Einaudi 1990; Hitzman

et al. 1992; Foose and McLelland 1995; Barton and Johnson

1996; Barton 1998). With respect to the source of the P for

these low Ti iron-oxide deposits, Barton and Johnson (1996)

proposed an evaporitic-source model.

The Agoriani apatite mineralization is similar to the latter

class of deposits in terms of the association of apatite with low-

Ti Fe-oxides (magnetite), the presence of REE-bearing miner-

als (monazite) that are considered to be of hydrothermal origin,

and abundant aqueous fluid inclusions within apatite. Although

the above distinct class of deposits and the Agoriani apatite-

magnetite association both appear to be hydrothermal in ori-

gin, the source for the P is different in each. Apart from apatite

that is a common accessory phase in all mafic ophiolitic rocks,

high whole-rock concentrations of P2O5 and abundant apatitehave been reported in some mafic ophiolitic rocks (Hynes 1972;

Gjata et al. 1995; Tables 1 and 2). In addition, amphibolite dikes

cross-cutting the Zidani, Greece, serpentinized peridotite, are

characterized by high contents of Ti (2.9 wt% TiO2) and P (up

to 0.71 wt% P2O5,) and contain ilmenite and apatite. A salient

feature of the latter dikes is the highest P content in the less-

altered samples (2 wt% H2O), whereas strongly deformed, al-

tered, vermiculite-bearing samples (11.7 wt% H2O) exhibit low

(0.1 wt%) P2O5 contents (Karkanas et al. 1996). Such a de-

crease in P content in the deformed, highly altered dikes from

the Zidani area, combined with the presence of small crystals

of apatite with replacement features, within strongly altered

pillow lavas (Economou-Eliopoulos, unpub. data) suggests thatP might be mobile and enriched in hydrothermal systems re-

lated to ophiolites.

Therefore, the composition of the apatite (chlor-hydroxyl-

apatite) and the presence of abundant, primary, two-phase, aque-

ous fluid inclusions (Fig. 4), coupled with the composition of

the associated magnetite and sulfides, may indicate formation

of apatite under hydrothermal conditions.

ACKNOWLEDGMENTS

We thank K. Barlas and E. Michaelides, University of Athens, Departmentof Geology, who performed the electron microprobe analyses. Anna Ewing-Rassios, IGME Kozani (Greece) is also thanked for reading this manuscript.Many thanks are expressed to the Editor Robert F. Dymek and Associate Editor

TABLE 2. Chacteristics of the apatite-magnetite mineralization in the Agoriani area (Othrys) and other Fe-Ti-oxide-apatite occurrences

Apatite FluidHost rock Apatite occurrence Fe-Ti oxides composition REE in apatite inclusions Origin

in apatite

anorthosites Ti-bearing high content,Nelsonite (il-ap rock) il, ru, Ti-mt F-apatite flat to positive slope rare cumulates and/or

of the REE-patterns immiscible liquidrich in Ti, P +/ Zr

monazite inclusionsalkaline/ negative to positive rare tocalc-alkaline low-Ti F,Cl-apatite slope of the abundant

mt (il, ru) REE-patterns

mafic/ peripheral parts and/or hydrothermal and/orultramafic along shear zones il, ru,mt F-(OH)-apatite n.d. n.d. metasomatic activity

ophiolites highly evolved meltsFe-Ti oxide-rich gabbro and/or il, mt n.d. n.d. n.d. and/or late-magmatic

along shear zones hydrous fluids

Agoriani, shear zones along margins pure mt Cl-(OH)-apatite inclusions of abundantOthrys of gabroic bodies with lherzolite monazite two-phase hydrothermal

liquid-rich

Notes: il = ilmenite, ru = rutile, mt = magnetite, n.d. = no available data.


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Brent E. Owens, and reviewers Robert S. Darling, SUNY College at Cortland,Allan Kolker and Eric Force, U.S Geological Survey, Reston, Howard Naslund,SUNY at Binghamton, for their suggestions and constructive criticism of ear-lier drafts of the manuscript.

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Occurrence of Apatite Associated With Magnetite in an Ophiolite Complex (Othrys), Greece

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