microstructures associated with deep crustal subduction
TRANSCRIPT
Microstructures associated with deep crustal subduction deformation in theCycladic Blueschist belt, Syros, Greece
Gabriel J. Nelson
Senior Integrative ExerciseMarch 10, 2004
Submitted in partial fulfillment of the requirements for a Bachelor of Arts degree fromCarleton College, Northfield, Minnesota
Table of Contents
Abstract -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 1Introduction -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 2Tectonic Setting -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 4Geology of Syros -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 5Microstructures and Mineralogy of Blueschists -- -- -- -- -- -- -- 8
Bimodal size distribution of glaucophane -- -- -- -- -- - 11Mineral inclusions in garnet -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -11Garnet pressure shadows -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --15
Discussion and Conclusions -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 18Acknowledgements -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -22References Cites -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - 23Appendix 1 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - 25Appendix 2 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - 29
Microstructures associated with deep crustal subduction deformation inthe Cycladic Blueschist belt, Syros, Greece
Gabriel J. Nelson
Senior Integrative Exercise
March 2004
Cameron Davidson, advisor
AbstractPressure shadows and inclusion trails in garnet from Blueschist facies rocks on
the Island of Syros, Greece reflect deformation events at blueschist facies conditionsduring Eurasia-Africa collision and subduction. Approximately 25% of all pressure
shadows are asymmetric, and 44% of all thin sections contain garnet inclusions at high
and low angles to foliation. To produce these microfabrics the deformation had aprogressively changing (non-coaxial) maximum direction of compression during
metamorphism.
Keywords: Syros, blueschist, deformation, garnet, pressure shadows, inclusions
2
Introduction
The island of Syros is in the Cycladic Blueschist belt of the Eastern
Mediterranean (Figure 1). It is likely that the rocks of the Cycladic Blueschist have been
the object of geologic study since early Phoenician influence in the region (Schumacher
and Helffrich, 2001). These metamorphic rocks formed during subduction at deep crustal
depths of 50 to 60 km and temperatures of 450-500° Celsius (Gealey, 1988; Lister et al.,
1984; Rosenbaum et al., 2002), and the exhumation of these rocks has been attributed to
syn-orogenic and post-orogenic collapse processes (Jolivet and Faccenna, 2000; Lister
and Raouzaios, 1996). Exhumation models typically employ low angle detachment faults
producing non-coaxial shearing (Avigad et al., 1997; Lister and Raouzaios, 1996). These
models typically use observations gathered from fabrics formed during deformation at
shallow crustal levels (Rosenbaum et al., 2002). Deformation at deep crustal levels has on
the other hand been interpreted as coaxial (Rosenbaum et al., 2002). Studies of deep
crustal deformation have been done in part by the observation of high-pressure and low-
temperature fabrics preserved in blueschist facies rocks. These rocks typically have the
assemblage garnet + omphacite + glaucophane + quartz (Rosenbaum et al., 2002).
Rosenbuam et al. (2001) concluded that the blueschist facies rocks of Syros record
multiple deformation events based on mineral inclusion trails in garnet and the geometry
of pressure shadows.
Over the past four years the Keck consortium has sent three teams of
undergraduates to addresses geologic problems on the island of Syros. This paper is the
result of the 2003 Keck project to Syros lead by Jack Cheney and Tekla Harms (Amherst
College), John Brady (Smith College), and John Schumacher (Bristol University). This
20°
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40° 40°
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H H H H H H H H H H H H H
H H
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OMC - M.Weinelt H H H H H H H
Greece
AlbaniaItaly
Bulgaria
Turkey
Syros
Hellenic Trench Pliny/S
trabo
Trench0 100km
inferred extension:
GMT Jan 11 16:32OMC - M.Weinelt
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Syros
SifnosSerifos Paros Naxos
Kea
Kithnos
Milos IosAmorgos
Ikaria
Mykonos
Tinos
AndrosEuboia
Cycladic blueschist belt Blueschist-facies carbonatesGranitic rocksUltramafic rocks
C yc lades
AfricanPlate
Motion
after Blake et al. (1984)
Figure 1. Geographic and Geologic of the Cyclades and Syros, from J.C. Schumacher (1999)
3
4
study is one project from the 2003 geology project to Syros with the support of the
KECK consortium. This paper takes a fresh look at the fabrics recorded by the blueschist
facies rocks of Syros. Microfabrics of glaucophane crystals suggest deformation occurred
in isolated bands on the scale of a thin section. Garnet inclusion trails and pressure
shadows around garnets suggest that deep crustal deformation was non-coaxial. The
finding of non-coaxial deformation agrees with conclusions of shallow crustal
deformation during the same exhumation event (Jolivet and Faccenna, 2000; Lister and
Raouzaios, 1996), but contradict the conclusions of Rosenbaum et al. (2002) about deep
crustal deformation in these rocks.
Tectonic Setting
The tectonic story of the lithologic package of the Cycladic Blueschist belt begins
in the Triassic and Jurassic. The tensional forces responsible for the fragmenting Pangaea
created rifting between what are today the African and Eurasian plates (Gealey, 1988).
The rifting formed the Hellenides Platform and the Pindos-Cyclades ocean basin between
the two plates (Papanikolaou, 1987). The sedimentary protoliths of the marbles, pelitic
schists, and metabasites that compose the Cycladic Blueschist belt formed in the Pindos-
Cycladic ocean basins. The extensional forces became compressional in the Late
Cretaceous when the relative motions of the Africa and Eurasia plates changed (Jolivet
and Faccenna, 2000). The ocean basin closed, ophiolites obducted, and subduction began
northward along the Pindos Zone (Gealey, 1988). The collision and subduction date of
this tectonic model fit with zircon ages of 78Ma, interpreted as the time of subduction
metamorphism (Brocker and Enders, 2001). The magnitude of the plate collision slowed
5
the absolute motion of the African plate (Jolivet and Faccenna, 2000). The slowing of the
African plate caused trench-rollback to the Hellenic Trench, changing plate boundaries
between the African and Cycladic microplate (Gealey, 1988).
The rollback lead to the back arch extension in the Aegean around 25-11Ma
(Lister et al., 1984). Normal and some listeric faults were active in the region since at
least the late Miocene (Papanikolaou, 1987) due to the positioning in the back arc of two
trench systems (Avigad et al., 1997) (Figure 1). The extensional processes allowed for the
exposure of the high-pressure metamorphic rocks formed during subduction before trench
rollback. This sequence of events formed, subducted, and later exposed the Cycladic
Blueschist belt rocks (Gealey, 1988; Jolivet and Faccenna, 2000).
Geology of Syros
The name “Syros” is derived from two Phoenician words meaning “happy” and
“rock” (Schumacher and Helffrich, 2001). After Phoenician naming practices the island
of Syros does not appear in significant geologic context until the late nineteenth century.
In 1845 Hausmann first described glaucophane from the island of Syros. After Hausmann
there was another break in the geologic consideration of this Aegean isle. Extensive
studies of the geology of Syros did not appear in English language geologic papers until
John Ridely’s work in the late 1960.
Syros is composed of alternating packages of shallow northeasterly dipping pelitic
schists, marbles, and metabasites (Figure 2). Deformational features notable on a map
scale include tectonic duplication represented by the alternating packages of rock types
(Dixon, 1987), isoclinal folding on the kilometer scale (Papanikolaou, 1987), and several
Marbles
Schists
Metabasites
Serpentinite
Vari Gneiss
0 3km
N
Figure 2. Syros and its basic lithology, modified from Dixon and Ridley (1987).
0 3km
N
Figure 3. Names, locations, and thin sectionsfrom field sites on Syros.
San MichaelKastri
Paradice
Windmill Hill
North Ermopoli
Kini Airport
Charrasonis
Perdiki
Katerghaki
Sample Locations with location names
Total Samples
0-4
5-10
14
6
7
fault zones cutting across the island (Figure 2). Faults are identified by zones of
serpetintization and brecciation.
The metamorphic rocks of Syros contain greenschist, eclogite, and blueschist. The
eclogites, and blueschist facies rocks developed during high-pressure subduction
metamorphism at 40 – 80 Ma (Brocker and Enders, 2001; Lister and Raouzaios, 1996;
Ridley and Dixon, 1984). The temperatures and pressures were approximately 14kbar
and 450°-500°C (Dixon, 1976). During this metamorphism the blueschist developed
foliation and lineation (Rosenbaum et al., 2002). These structures are represented by the
preferential orientation of micas into the near horizontal foliation and preferred alignment
of glaucophane into the lineation. The greenschist is a retrograding overprint of
eclogite/blueschist and is more pervasive in the south of the island. It is identifiable by
the chlorite overgrowth of garnet and glaucophane crystals. Greenschist metamorphism
occurred at similar temperatures to the blueschist/eclogite metamorphism but at much
shallower depths (Schiestedt and Matthews, 1987). The overprinting happened 20-25 Ma
(Lister et al., 1984; Schiestedt and Matthews, 1987). The preservation of some blueschist
during exhumation required maintaining high subduction type pressures while lifting the
blueschists to surface conditions without passing the low pressure phase of greenschist
overprinting (Wijbrans et al., 1993). Wijbrans et al. (1993) proposed thrust faulting as a
result of repeated delamination of lighter supercrustal rocks of the subducting plate. The
story of metamorphism and subsequent exhumation is not a complete one. Continued
work in this area is identifying further constraints on pressures, temperatures, timing,
deformation, and chemical processes in the framework of subduction and exhumation
processes.
8
Microstructures and Mineralogy of Blueschists
Blueschist facies rocks on Syros have the mineral assemblage garnet +
glaucophane + omphacite + epidote + white mica + quartz + sphene (Rosenbaum et al.,
2002). Samples of blueschist were collected from around the island (Figure 3).
Approximately eighty geochemical spot analyses were done on four thin sections of
blueschist with a Scanning Electron Microscope (SEM) that has an Energy Dispersive X-
ray Spectrometry (EDS) (Appendix 1). Results shows that garnet composition is 60%-
65% almandine and 16%-18% grossular with lesser components of pyrope and
spessertine (Figure 4). Transects across garnet crystals show a reduction in magnesium
corresponding to an increase in manganese from rim to core (Figure 5). These results are
consistent with findings of Ridley and Dixon (1984). All glaucophane crystals have the
chemical composition of true glaucophanes (Figure 6), and show a reduction in ferrous
iron from rim to core (Figure 7). Variation in iron content from rim to core of
glaucophane crystals has been noted by Ridley and Dixon (1984) and Schiestedt et al.
(1987).
The blueschists of Syros have a near horizontal foliation defined by the preferred
orientation of mica crystals and a lineation within the plane of this foliation defined
predominately by glaucophane crystals (Dixon, 1987). Garnet crystals have trails of
mineral inclusions composed of white mica, quartz, and glaucophane. Pressure shadows
around garnet crystals are composed of quartz, white mica, glaucophane, and chlorite.
100% Almandine (FeO)
50% Pyrope (MgO)
50% Grossular + Spessartine (CaO+MnO)
Figure 4. Garnet chemical composition plot. Note that the Grossular + Spessartine and the Pyrope verticies are at 50% composition.
Figure 5. Transects from rim to core of three garnets. Garnets show reduction in Mg and an increase in Mn toward the core. Average transect is 0.9 mm.
0
0.04
0.08
0.12
0.16
0.20
XMg XMnRim Core
9
0
0.5
1
0 0.5 1
Fe2/Fe2+Mg
Ferro-Glaucophane Riebeckite
Magnesio-RiebeckiteGlaucophane
Figure 6. Sodic amphibole composition plot. All glaucophane crystals analyzed plot as true glaucophane.
Fe+3/(Fe+3+AL)
Fe+
2 /(F
e+2 +
Mg)
0.7
0.9
1.1
1.3
1.5
Rim Core
Ferrous Iron
Figure 7. Transects from rim to core of seven gaucophane crystals. Glaucophane shows a reduction in ferrous iron toward the core.
Fer
rous
Iron
10
11
Bimodal Size Distribution of Glaucophane
The size of glaucophane crystals in thin section remains within approximately
30% of an average glaucophane crystal size. There is the exception of a small population
of thin sections (13 of 48) that show glaucophanes where crystal size is not uniform, but
instead has a bimodal size distribution. In thin sections with bimodal size distribution,
larger glaucophane crystals form bands parallel with foliation corresponding to areas of
the highest concentration of garnet (Figure 8). Ten thin sections with bimodal size
distribution of glaucophane are from one field location (Figure 9). Geochemical analyses
from larger and smaller glaucophanes in thin sections with bimodal size distribution show
no conclusive chemical difference between sizes of crystals (Figure 10).
Mineral Inclusions in Garnet
Roughly 97% of garnets observed in the thin sections contain mineral inclusions.
The inclusions mainly consist of quartz, white mica, and glaucophane crystals. During
garnet growth minerals are enveloped, which preserves crystal orientation (Davis and
Reynolds, 1996). Consequently, textures present in the rock before or during garnet
growth can be overgrown and preserved in the garnet.
In the thin sections, garnet inclusions trails are straight (Figure 11) or curved
(Figure 12, 13). Additionally, the trails are at high or low angles to the shallowly dipping
foliation. Within individual thin sections, garnet inclusion trails exist that fit the four
combinations of curved/straight and high/low angle types of trails. Trails that are at an
angle of greater than 45° to foliation are considered at a high-angle to foliation (Figure
11), trails less than 45° to foliation are at a low-angle to foliation. Geographically, nine
10
12
0
4
8
12
NorthErmopoli
Airport Charrasonis
Figure 8. Pictomicrograph photo of bimodal size distribution of glaucophane in association with garnets. Sample number 26121.
Figure 9. Total thin-sections with bimodal size distribution of glaucophanes from locations across Syros. Locations are arranged from north to south on the island. Locations with no observed bimodal distribution were omitted.
area
of l
arge
r gl
auco
phan
esar
ea o
f sm
alle
r gl
auco
phan
esGarnet
Garnet
Garnet
Garnet
Garnet
1 mm
12
0
0.5
0 0.1 0.2 0.3 0.4 0.5Fe+3 / (Fe+3 + Al)
Small GlaucophanesLarge Glaucophanes
Figure 10. Composition plot of large and small glaucophane crystals on the glaucophane quadrant of a sodic amphibole plot. Variation in crystal size shows no correlation with respect to chemical composition.
Fe2+
/(F
e2+ +
Mg)
Figure 11. Pictomicrograph photo of straight garnet inclusions at high angle to foliation. Inclusion trend is marked with white arrow. Foliation is horizontal, sample number 16123
0.4
0.1
0.3
0.2
13
15
out of ten field locations have inclusion trails at high and low angles to foliation, and all
field locations have curved and straight inclusion trails. Forty-four percent of thin
sections contain garnet inclusions at both high and low angles to foliation. High angle
garnet inclusion trails are present in 6% more thin sections than low angle inclusion
trails. (Figure 14).
Garnet Pressure Shadows
Sampling on Syros was restricted to blueschist with garnets likely to exhibit
pressure shadows. Samples came from outcrops with deformation textures such as
elongate boudens or garnet pressure shadows observable by hand-lens. Each set of garnet
pressure shadows from oriented thin section was recorded (Appendix 2) as a sigma, delta,
symmetric, or undetermined (Davis and Reynolds, 1996). The symmetry determination is
made by imagining a line parallel to foliation through the center of the porphyroblast,
which in this study is the center of garnet, and evaluating the position of the pressure
shadows in relationship to the line (Figure 15) (Passchier and Simpson, 1986). Symmetric
pressure shadows are centered on a line through the center of the porphyroblastic system
(Figure 16). Sigma and delta porphyroblasts are both asymmetric (Figure 15, 16). Garnet
pressure shadows with undetermined pressure shadows are of two types. One type lacks
noticeable pressure shadows and the other has highly distorted pressure shadows. Highly
distorted pressure shadows generally occur in close proximity to other garnets. Pressure
shadows bend and distort around the large crystals, so that the tips do not represent
deformation around one porphyroblast, but instead indicate significantly more
complicated deformation associated with interaction of several porphyroblasts.
0
5
10
15
20
25
30
SanMichael
KastriParadiceWindmill
HillNorth
Ermopoli
Kini
Airport
Charrasonis
Perdiki
Inclusions at low angle to Foliation
Inclusions at High Angle to Foliation
Figure 14. Total thin-sections, by location, with garnets containing inclusion trails at a high or low angle to the foliation. Locations are arranged from north to south on the island.
San
M
icha
el
Kas
tri
Par
adic
e
Win
dmill
Hill
Nor
th
Erm
opol
i
Kin
i
Airp
ort
Cha
rras
onis
Per
diki
Kat
ergh
aki
16
18
Of the approximately 1200 garnet pressure shadows observed, 25% are
asymmetrical and 40% are symmetrical (Figure 17). The asymmetric pressure shadows
are less abundant than symmetric ones but constitute a significant proportion of total
garnet pressure shadows. Asymmetric pressure shadows are also a substantial population
of the pressure shadows observed from each field location (Figure 18).
Discussion and Conclusions
Lister and Raouzaios (1996) suggest that metamorphic mineral growth in the
Cycladic Blueschist belt precedes tectonically driven deformational events. It would be
possible, but unlikely, that bimodal size distribution is the result of one size of
glaucophane crystals growing during an early metamorphic growth and the other size
crystals forming in a later metamorphic growth. Preliminary tests show that the crystals
of larger and smaller glaucophanes do not have a distinct chemistry (Figure 10). Ridley
and Dixon (1984) concluded that chemical equilibrium changed progressively during the
formation of high-pressure minerals. Additionally, The chemical zoning noted in
transects across of crystals (Figure 5 and 7) within these blueschist facies rocks has been
interpreted as prograde metamorphic mineral growth (Schiestedt et al., 1987), and a
record of fluid-enhanced chemical exchange (Dixon, 1987). The progressive change in
chemical equlibrium, and chemical zoning as a result of different crystal growth events
would indicate that crystals forming at different times would have different chemistries
reflecting the progressive change in chemical equilibrium of the rock. This is seemingly
not true for the different sizes of glaucophanes in thin sections with bimodal size
290
470417
0
100
200
300
400
500
Asymmetrical Symmetrical Undetermined
0 3km
N
San Michael
North Ermopoli
Airport
Katerghaki
Charrasonis
Kini
AsymmetricalSymmetrical UndeterminedSample Locations
Figure 18. Syros with thin section analysis by sample location. Each graph shows relative proportions of garnet porphyroblastic systems. Only locations with more than one hundred porphyroblastic systems recorded are shown.
Figure 17. Total of each type of porphyroblastic system observed in thin section
19
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distribution, so the size variation is likely due to something other than glaucophanes from
two blueschist metamorphic growth events.
The variation in crystal size may instead be the result of the restrictive presence of
fluids. If fluids favorable to the growth of glaucophane were concentrated in zones
defined by garnet populations, the result would be larger glaucophanes in these zones.
Fluids could also be concentrated as a result of movement to shielded areas and away
from deformational shear bands. The pressure shadows around garnet porphyroblasts are
a result of mineral recrystalization of reaction-softened material from the matrix in areas
shielded from deformation, (for example quartz and white mica) (Passchier and Simpson,
1986). These shielded locations may also concentrate fluids favorable to glaucophane
growth. The shield locations could also simply preserve larger glaucophane crystals.
Ridley and Dixon (1984) found that larger glaucophanes from one growth event in one
field location are broken into smaller polygonal crystals in other field locations. This
breaking of glaucophane into smaller crystals may also be evident in bimodal
glaucophane bands on the scale of a single thin section.
Rosenbaum et al. (2002) concluded that there are three deformational events at
blueschist facies conditions that are preserved in blueschist fabrics. The fabric from the
earliest deformational event is preserved as inclusion trails in garnet porphyroblasts
(Rosenbaum et al., 2002). The next deformation event is evidenced by the shallowly
dipping foliation and symmetric features such as pressure shadows (Rosenbaum et al.,
2002). Rosenbaum et al. (2002) found that garnet inclusions from the earlier
deformational event are typically orthogonal to the near horizontal foliation that resulted
in the later deformational event. They concluded that the porphyroblast inclusions are a
21
result of coaxial compression that was perpendicular to the later coaxial compression
producing foliation and symmetric pressure shadows. Therefore the first deformation was
during the African Eurasian continental collision resulting in deep crustal thickening. The
later deformation was separate from the earlier one and signifies that deep crustal
thinning in the horizontal direction was occurring during orogenic collapse (Rosenbaum
et al., 2002). The third fabric and deformational event produced isolated non-coaxial
shear bands (Rosenbaum et al., 2002).
Shear bands, as noted by Rosenbaum et al. (2002), were not observed in this
study. Sampling methods could have excluded blueschist with deformational fabrics
obscuring clear pressure shadows from an earlier deformation, and thus representative
shear bands of late blueschist deformation. It is also possible that the isolated shear bands
noted by Rosenbaum et al. (2002) produced the bands of larger and smaller glaucophanes
crystals (Figure 14).
Microstructures described by Rosenbaum et al. (2002) as indicators of the two
earliest blueschist metamorphic events were observed for this study, but the results and
interpretations of this study differ from those of Rosenbaum et al. (2002). The inclusion
trails in garnets were seen at high angle (greater than 45°) (Figure 11) to foliation,
including trails orthogonal to foliation. Inclusion trails were also often seen at low angles
(less than 45°) to foliation (Figure 12). The variation in inclusion angle is likely to be the
cause of garnet rotation after overgrowth of the earlier blueschist fabric. In addition, the
inclusion trails preserved in garnets are curved, (Figure 13) probably due to rotation of
the garnet crystal during growth. Asymmetric pressure shadows are 10%-40% of the
pressure shadows from each field location around the island (Figure 18). The asymmetric
22
pressure shadows (Figure 16) are likely the result of a non-coaxial deformation (Passchier
and Simpson, 1986). The microfabrics of garnet inclusion trails and porphyroblastic
systems indicated that blueschist deformational events were non-coaxial, similar to other
studies on the Aegean island of Sifnos (Lister and Raouzaios, 1996). The implication is
that maximum compressional directions change progressively during high-pressure
subduction deformation, and that orogenic collapse was occurring during continental
collision.
Acknowledgments
Thanks to all of the other undergraduate students on the 2003 Keck research trip to Syros
. There are no others with whom I would rather toss back a Mythos and discuss beautiful
blue rocks. I would like to thank John Brady, John Schumacher, Tekla Harms, and Jack
Cheney for dedicating themselves to provide me and other students the amazing
experience of Syros’ geology. Additional thanks to Jack Cheney for his never ending
passion for discussion about rocks, to Tekla Harms for provide direction to my field
work, and John Brady for the assistance and use of the Smith College SEM with EDS as
well as feeding and housing me for my stay at Smith College. I would be remised to not
thank Cameron Davidson for his help in the field, at the microscope, with drafts, papers,
and ideas. This project would not have been possible without these people or the funding
of the Keck consortium, the Charles W. Potts Endowment fund, and Thomas P. Cook
Educational Trust. Without these sources of financial support I would not have been able
to go to Greece, go to Amherst and Smith Colleges, ship rock samples home, have thin
sections made, or complete any part of this project.
23
References CitedAvigad, D., Garfunkel, Z., Jolivet, L., and Azañón, J. M., 1997, Back arc extension and
denudation of Mediterranean Eclogites: Tectonics, v. 16, no. 6, p. 924-941.
Brocker, M., and Enders, M., 2001, Unusual bulk-rock composition in eclogite-faciesrocks from Syros and Tinos (Cyclades, Greece): implications for U-Pb zircongeochronology: Chemical Geology, v. 175, p. 581-603.
Davis, G. H., and Reynolds, S. J., 1996, Structural Geology: New York, John Wiley &Sons, Inc.
Dixon, J. E., 1976, Glaucophane schists of Syros, Greece (abstract): Geologic SocietyBulletin of France, v. 7, p. 280.
Dixon, J. E. a. R., J., 1987, Syros (field trip excursion), in Helgeson, H. C., ed., Chemicaltransport in metasomatic processes: Nato Advanced Study Institutes: Dordrecht,D. Reidel Publishing Company, p. pp. 489-500.
Gealey, W. K., 1988, Plate tectonic evolution of the Mediterranean-Middle East region:Tectonophysics, v. 155, p. 285-306.
Jolivet, L., and Faccenna, C., 2000, Mediterranean extension and the Africa-EurasiaCollision: Tectonics, v. 19, no. 6, p. 1095-1106.
Lister, G. S., Banga, G., and Feenstra, A., 1984, Metamorphic core complexes ofCordilleran type in the Cyclades, Aegean Sea, Greece: Geology, v. 12, p. 221-225.
Lister, G. S., and Raouzaios, A., 1996, The tectonic significance of a porphyroblasticblueschist facies overprint during Alpine orogenesis: Sifnos, Aegean Sea, Greece:Journal of Structural Geology, v. 18, no. 12, p. 1417-1435.
Papanikolaou, D. J., 1987, Tectonic Evolution of the Cycladic Blueschist Belt (AegeanSea, Greece), in Helgeson, H. C., ed., Chemical Transport in MetasomaticProcesses, D. Reidel Publishing Company, p. 429-450.
Passchier, C. W., and Simpson, C., 1986, Porphyroclast systems as kinematic indicators:Journal of Structural Geology, v. 8, no. 8, p. 831-843.
Ridley, J., and Dixon, J. E., 1984, Reaction pathways during the progressive deformationof a blueschist metabasite: the role of chemical disequilibrium and restrictedrange equilibrium: Journal of Metamorphic Geology, v. 2, p. 115-128.
24
Rosenbaum, G., Avigad, D., and Mario, S.-G., 2002, Coaxial flattening at deep levels oforogenic belts: evidence from blueschist and eclogites on Syros and Sifnos(Cyclades, Greece): Journal of Structural Geology, v. 24, no. 9, p. 1451-1462.
Schiestedt, M., Altherr, R., and Matthews, A., 1987, Evolution of the CycladicCrystalline Complex: Petrology, Isotope Geochemistry and Geochronolgy, inHelgeson, H. C., ed., Chemical Transport in Metasomatic Processes, D. ReidelPublishing Company, p. 389-428.
Schiestedt, M., and Matthews, A., 1987, Transformation of blueschist to greenschistfacies rocks as a consequence of fluid infiltration, Sifnos (Cycladed), Greece:Contributions to Mineralogy and Petrology, v. 97, p. 237-250.
Schumacher, J. C., and Helffrich, G., 2001, Bristol Mapping Course: Syros and theCyclades.
Wijbrans, J. R., Wees, J., Stephenson, R., and Cloetingh, S. A. P. L., 1993, Pressure-temperature-time evolution of the high-pressure metamorphic complex of Sifnos,Greece: Geology, v. 21, p. 443-446.
Appendix 1. Table 1 SEM analyses of garnet crystals
Garnet DataSample # 16103 16103 16103 16103 16103 16103 16103 26125 26125 26125 26125 26125 26125analysis # 5 6 7 8a 8b 8c 8d 1a 1b 1c 1d 2a 2b
RIM CORE RIM CORE RIMWt% oxideMgO 2.578 2.156 2.041 2.206 1.166 0.966 0.758 4.326 4.115 3.807 3.763 4.405 4.401Al2O3 21.566 21.641 21.337 21.685 21.261 20.833 21.351 21.467 21.239 21.190 21.314 21.127 21.774SiO2 37.063 37.336 36.990 36.857 36.441 36.900 36.655 37.479 37.314 37.116 37.498 37.848 37.320CaO 9.220 8.741 8.925 8.303 8.233 8.189 8.225 6.250 6.005 6.140 6.258 6.366 5.727MnO 0.259 0.235 0.387 0.184 0.934 1.156 2.210 1.972 2.329 2.403 2.410 1.876 2.186FeO 28.291 29.236 29.010 29.831 30.820 30.100 29.792 27.833 27.172 27.536 27.378 27.155 27.255total 98.979 99.345 98.690 99.066 98.855 98.143 98.992 99.327 98.174 98.193 98.622 98.777 98.663
Stoichiometry [Cations based on 12 O]Mg 0.308 0.257 0.245 0.264 0.141 0.118 0.092 0.512 0.493 0.457 0.449 0.523 0.523Al 2.035 2.038 2.027 2.054 2.037 2.004 2.043 2.011 2.010 2.011 2.011 1.982 2.046Si 2.968 2.984 2.981 2.962 2.963 3.012 2.976 2.978 2.996 2.989 3.001 3.013 2.976Ca 0.791 0.748 0.771 0.715 0.717 0.716 0.716 0.532 0.517 0.530 0.537 0.543 0.489Mn 0.018 0.016 0.026 0.013 0.064 0.080 0.152 0.133 0.158 0.164 0.163 0.127 0.148Fe 1.895 1.954 1.955 2.005 2.096 2.055 2.023 1.850 1.825 1.854 1.833 1.808 1.818
Pyrope 0.102 0.086 0.082 0.088 0.047 0.040 0.031 0.169 0.165 0.152 0.151 0.174 0.176Almandine 0.629 0.657 0.652 0.669 0.694 0.692 0.678 0.611 0.610 0.617 0.615 0.603 0.610Spessartine 0.006 0.005 0.009 0.004 0.021 0.027 0.051 0.044 0.053 0.055 0.055 0.042 0.050Grossular 0.263 0.252 0.257 0.239 0.238 0.241 0.240 0.176 0.173 0.176 0.180 0.181 0.164Mg/Fe 0.162 0.131 0.125 0.132 0.067 0.057 0.045 0.277 0.270 0.246 0.245 0.289 0.288
Garnet DataSample # 26125 26125 26125 26125 56141 56141 56141 56141 56141 56141 56141 56141 56141analysis # 2c 2d 2e 2f 5 13 14a 14b 14c 14d 15 16a 16b
COREWt% oxideMgO 3.781 3.704 3.623 3.213 3.507 2.817 3.306 3.168 3.162 3.078 3.348 3.926 2.883Al2O3 21.664 21.316 21.192 21.274 21.612 21.986 22.056 22.267 22.009 22.244 22.171 21.912 22.023SiO2 37.708 37.608 37.547 37.439 37.825 38.310 37.900 38.089 37.837 38.450 38.562 38.555 38.211CaO 6.065 6.564 5.636 6.078 8.642 8.969 8.883 8.995 8.125 9.129 9.165 8.287 9.070MnO 2.583 2.907 3.617 4.483 0.621 1.753 0.728 0.752 0.755 0.887 0.702 1.043 0.829FeO 27.018 26.592 26.841 25.598 27.849 26.061 27.615 27.894 27.970 27.009 27.420 27.553 26.935total 98.818 98.692 98.455 98.084 100.056 99.896 100.489 101.166 99.857 100.797 101.367 101.275 99.951
Stoichiometry [Cations based on 12 O]Mg 0.449 0.441 0.433 0.386 0.412 0.330 0.387 0.368 0.372 0.358 0.387 0.454 0.337Al 2.034 2.008 2.005 2.019 2.009 2.038 2.039 2.047 2.047 2.044 2.027 2.006 2.037Si 3.004 3.006 3.014 3.015 2.983 3.013 2.974 2.971 2.987 2.997 2.992 2.994 2.998Ca 0.518 0.562 0.485 0.525 0.730 0.756 0.747 0.752 0.687 0.762 0.762 0.690 0.762Mn 0.174 0.197 0.246 0.306 0.041 0.117 0.048 0.050 0.050 0.059 0.046 0.069 0.055Fe 1.800 1.777 1.802 1.724 1.837 1.714 1.812 1.819 1.846 1.761 1.779 1.790 1.767
Pyrope 0.153 0.148 0.146 0.131 0.136 0.113 0.129 0.123 0.126 0.122 0.130 0.151 0.115Almandine 0.612 0.597 0.608 0.586 0.608 0.588 0.605 0.609 0.625 0.599 0.598 0.596 0.605Spessartine 0.059 0.066 0.083 0.104 0.014 0.040 0.016 0.017 0.017 0.020 0.016 0.023 0.019Grossular 0.176 0.189 0.163 0.178 0.242 0.259 0.249 0.251 0.232 0.259 0.256 0.230 0.261Mg/Fe 0.249 0.248 0.241 0.224 0.224 0.193 0.213 0.202 0.201 0.203 0.218 0.254 0.191
Note: Arrows from rim to core indicates mineral analyses along indivigual crystals transects 25
Appendix 1. Table 2 SEM analyses of glaucophane crystals Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 8.011 7.797 7.955 7.797 7.956 7.776 8.008 7.800 8.061 7.857 7.921 7.754 7.998 7.823 7.979 7.803Al 1.780 1.733 1.841 1.804 1.836 1.794 1.814 1.767 1.730 1.686 1.821 1.782 1.846 1.806 1.837 1.797Fe+3 0.000 1.226 0.000 0.913 0.000 1.040 0.000 1.191 0.000 1.164 0.000 0.969 0.000 1.006 0.000 1.017Fe+2 1.260 0.000 0.932 0.000 1.064 0.000 1.222 0.000 1.194 0.000 0.989 0.000 1.028 0.000 1.040 0.000Mg 2.005 1.952 2.324 2.278 2.190 2.140 2.025 1.972 2.073 2.021 2.326 2.277 2.134 2.087 2.158 2.111Ca 0.036 0.035 0.089 0.087 0.058 0.057 0.032 0.031 0.040 0.039 0.085 0.083 0.052 0.051 0.039 0.038Na 2.013 1.960 1.967 1.928 2.042 1.996 1.969 1.918 1.951 1.902 2.054 2.011 2.041 1.996 2.097 2.050
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+AlFe2/Fe2+Mg
Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 8.012 7.782 7.977 7.713 7.979 7.725 7.902 7.648 7.989 7.735 7.992 7.706 7.957 7.669 7.916 7.699Al 1.812 1.760 1.760 1.702 1.789 1.732 1.917 1.856 1.828 1.769 1.683 1.623 1.729 1.666 1.922 1.869Fe+3 0.000 1.320 0.000 1.524 0.000 1.466 0.000 1.478 0.000 1.466 0.000 1.644 0.000 1.670 0.000 1.260Fe+2 1.359 0.000 1.577 0.000 1.515 0.000 1.527 0.000 1.515 0.000 1.704 0.000 1.733 0.000 1.296 0.000Mg 1.834 1.782 1.731 1.673 1.765 1.708 1.677 1.623 1.672 1.618 1.672 1.612 1.651 1.591 1.886 1.834Ca 0.040 0.038 0.037 0.036 0.042 0.041 0.091 0.088 0.065 0.063 0.042 0.040 0.061 0.059 0.093 0.090Na 2.051 1.992 2.121 2.050 2.074 2.008 2.052 1.986 2.058 1.992 2.147 2.070 2.095 2.019 2.021 1.966
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+AlFe2/Fe2+Mg 0.474 0.477 0.474 0.3940.414 0.450 0.433 0.463
0.006 0.097 0.124 0.0350.033 0.083 0.085 0.041
2.057 2.138 2.084 2.0182.048 2.113 2.066 2.0480.065 0.042 0.061 0.0930.039 0.037 0.042 0.0911.671 1.665 1.642 1.8831.832 1.725 1.758 1.6741.504 1.517 1.479 1.2241.296 1.413 1.343 1.4430.010 0.181 0.244 0.0700.061 0.159 0.166 0.0811.827 1.677 1.719 1.9191.810 1.754 1.782 1.9147.987 7.960 7.915 7.9048.001 7.950 7.950 7.888
95.244 96.294 94.670 94.87095.632 96.542 95.819 95.7477.436 7.768 7.446 7.3307.493 7.738 7.536 7.4380.426 0.273 0.393 0.6090.261 0.245 0.278 0.5967.857 7.868 7.630 8.8998.719 8.214 8.341 7.90812.689 14.298 14.274 10.89611.510 13.339 12.758 12.83610.864 10.021 10.105 11.46710.893 10.566 10.692 11.43355.973 56.065 54.823 55.669
3c 3d 3e 41 2 3a 3b16103 16103 16103 1610316103 16103 16103 16103
0.322 0.253 0.320 0.3140.346 0.243 0.291 0.3680.107 0.100 0.012 0.0280.101 0.091 0.082 0.023
56.757 56.439 56.214 55.536
RIM
1.942 2.045 2.040 2.0942.005 1.959 2.035 1.9680.040 0.084 0.052 0.0390.036 0.089 0.058 0.0322.064 2.316 2.133 2.1561.997 2.315 2.182 2.0230.982 0.783 1.005 0.9861.056 0.744 0.898 1.1780.206 0.202 0.023 0.0530.198 0.184 0.163 0.0431.722 1.813 1.845 1.8351.772 1.834 1.829 1.8138.025 7.886 7.994 7.9707.977 7.923 7.928 8.000
99.000 95.948 95.749 97.62197.206 97.558 96.886 95.4587.439 7.615 7.562 7.9107.508 7.447 7.637 7.2290.274 0.569 0.348 0.2640.243 0.610 0.395 0.21110.284 11.219 10.287 10.5929.727 11.449 10.652 9.66810.554 8.504 8.833 9.09410.891 8.180 9.225 10.40310.853 11.105 11.254 11.40110.919 11.468 11.293 10.95659.595 56.936 57.465 58.36157.918 58.405 57.684 56.991
RIM CORE CORE RIM5 6 7 81 2 3 4
26123 26123 26123 2612326123 26123 26123 26123
RIM CORE CORE
Note: Arrows from rim to core indicates mineral analyses along indivigual crystals transects 26
Appendix 1. Table 3 SEM analyses of glaucophane crystals Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 8.075 7.832 8.003 7.778 8.010 7.812 8.038 7.818 8.105 7.846 8.030 7.833 7.994 7.793 8.028 7.831Al 1.623 1.574 1.678 1.631 1.690 1.648 1.709 1.662 1.594 1.543 1.622 1.582 1.719 1.676 1.680 1.639Fe+3 0.000 1.387 0.000 1.294 0.000 1.133 0.000 1.256 0.000 1.471 0.000 1.131 0.000 1.156 0.000 1.132Fe+2 1.430 0.000 1.332 0.000 1.162 0.000 1.291 0.000 1.520 0.000 1.160 0.000 1.186 0.000 1.160 0.000Mg 1.928 1.869 2.066 2.008 2.204 2.150 1.961 1.907 1.841 1.782 2.235 2.180 2.151 2.097 2.148 2.095Ca 0.029 0.029 0.063 0.061 0.052 0.051 0.043 0.042 0.019 0.018 0.090 0.088 0.043 0.042 0.070 0.068Na 2.054 1.992 2.033 1.976 2.055 2.005 2.131 2.073 2.038 1.973 2.044 1.994 2.106 2.053 2.091 2.040
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+AlFe2/Fe2+Mg
Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 8.011 7.798 7.948 7.735 8.000 7.732 8.065 7.781 8.038 7.780 7.929 7.782 7.908 7.762 8.041 7.763Al 1.726 1.680 1.689 1.643 1.561 1.509 1.389 1.340 1.554 1.504 1.863 1.828 1.892 1.857 1.710 1.651Fe+3 0.000 1.221 0.000 1.232 0.000 1.539 0.000 1.616 0.000 1.475 0.000 0.855 0.000 0.853 0.000 1.587Fe+2 1.254 0.000 1.266 0.000 1.592 0.000 1.675 0.000 1.524 0.000 0.871 0.000 0.869 0.000 1.644 0.000Mg 2.053 1.999 2.188 2.129 1.923 1.858 1.999 1.929 1.954 1.891 2.337 2.293 2.372 2.328 1.658 1.601Ca 0.061 0.059 0.061 0.060 0.101 0.098 0.128 0.124 0.090 0.087 0.141 0.138 0.116 0.114 0.029 0.028Na 2.044 1.990 2.113 2.056 2.085 2.016 1.969 1.900 2.050 1.984 1.998 1.961 1.976 1.939 2.045 1.974
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+Al0.395 0.271 0.233 0.4680.349 0.302 0.408 0.3790.137 0.000 0.072 0.0990.082 0.159 0.147 0.246
2.039 1.998 1.970 2.0362.037 2.099 2.073 1.9500.090 0.141 0.116 0.0290.061 0.061 0.100 0.1271.943 2.337 2.365 1.6512.047 2.173 1.911 1.9801.270 0.871 0.720 1.4501.095 0.941 1.316 1.2100.246 0.000 0.146 0.1870.154 0.317 0.267 0.4491.546 1.863 1.886 1.7031.720 1.677 1.552 1.3757.995 7.930 7.883 8.0087.984 7.893 7.954 7.986
96.602 91.822 93.035 92.47796.351 96.806 95.099 95.6307.493 7.125 7.144 7.1437.545 7.810 7.473 7.0780.596 0.909 0.761 0.1820.406 0.409 0.655 0.8339.290 10.839 11.157 7.5369.859 10.518 8.961 9.34812.912 7.199 7.282 13.31710.731 10.846 13.229 13.9609.346 10.928 11.254 9.82810.479 10.267 9.201 8.21156.965 54.823 55.437 54.47157.331 56.955 55.580 56.201
10f 1 2 310b 10c 10d 10e26125 56141 56141 5614126125 26125 26125 26125
0.415 0.308 0.319 0.3390.390 0.337 0.297 0.3970.118 0.092 0.094 0.0330.110 0.143 0.120 0.000
2.028 2.037 2.098 2.0892.045 2.021 2.045 2.1310.018 0.090 0.043 0.0700.029 0.062 0.052 0.0431.832 2.227 2.143 2.1451.919 2.054 2.193 1.9611.301 0.992 1.004 1.1011.225 1.046 0.926 1.2910.212 0.163 0.178 0.0580.200 0.278 0.229 0.0001.587 1.616 1.712 1.6781.616 1.668 1.681 1.7098.068 8.002 7.963 8.0188.040 7.955 7.970 8.039
95.269 96.867 96.933 96.09495.922 96.724 95.734 95.8867.374 7.605 7.834 7.7207.502 7.505 7.562 7.8140.122 0.608 0.290 0.4660.195 0.418 0.349 0.2888.665 10.813 10.410 10.3139.159 9.922 10.547 9.35312.751 10.001 10.228 9.93112.115 11.398 9.909 10.9779.489 9.923 10.520 10.2049.756 10.194 10.228 10.30856.869 57.918 57.651 57.46157.195 57.287 57.138 57.147
RIM CORE7 8 9 10a3 4 5 6
26125 26125 26125 2612526125 26125 26125 26125
Fe2/Fe2+Mg
Note: Arrows from rim to core indicates mineral analyses along indivigual crystals transects 27
Appendix 1. Table 4 SEM analyses of glaucophane crystals Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 7.978 7.836 7.932 7.788 7.986 7.806 7.972 7.814 7.923 7.788 7.982 7.819 8.007 7.817 7.985 7.791Al 1.872 1.838 1.875 1.841 1.895 1.852 1.895 1.857 1.904 1.871 1.900 1.861 1.869 1.824 1.837 1.793Fe+3 0.000 0.820 0.000 0.836 0.000 1.034 0.000 0.912 0.000 0.781 0.000 0.944 0.000 1.091 0.000 1.118Fe+2 0.835 0.000 0.851 0.000 1.058 0.000 0.931 0.000 0.795 0.000 0.963 0.000 1.118 0.000 1.146 0.000Mg 2.318 2.277 2.399 2.356 2.089 2.042 2.256 2.212 2.399 2.358 2.192 2.147 2.021 1.973 2.063 2.013Ca 0.128 0.126 0.108 0.106 0.041 0.040 0.040 0.040 0.110 0.108 0.034 0.034 0.051 0.049 0.074 0.072Na 1.909 1.875 1.930 1.895 1.998 1.954 1.971 1.932 1.991 1.957 1.989 1.948 1.986 1.939 1.981 1.933
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+AlFe2/Fe2+Mg
Glaucophane DataSample #analysis #
Wt% oxideSiO2Al2O3FeOMgOCaONa2OTotal
Stoichiometry [Cations Bases on 23 Oxygens]All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric All Ferrous All Ferric
Si 8.050 7.835 7.968 7.831 7.953 7.813 8.031 7.809 8.019 7.823 7.758 7.497Al 1.805 1.757 1.846 1.814 1.896 1.862 1.790 1.741 1.742 1.699 0.559 0.540Fe+3 0.000 1.227 0.000 0.790 0.000 0.811 0.000 1.270 0.000 1.126 0.000 1.550Fe+2 1.260 0.000 0.804 0.000 0.825 0.000 1.306 0.000 1.155 0.000 1.604 0.000Mg 1.890 1.840 2.388 2.347 2.356 2.314 1.849 1.798 2.031 1.982 3.122 3.017Ca 0.044 0.043 0.115 0.113 0.078 0.077 0.030 0.029 0.180 0.175 1.691 1.634Na 1.996 1.943 1.974 1.940 1.980 1.945 2.137 2.078 1.968 1.919 0.456 0.440
Stoichiometry [Cations based Si + Al + Fe(total) + Mg = 13]SiAlFe+3Fe+2MgCaNa
Fe3/Fe3+AlFe2/Fe2+Mg
1.976 0.454
0.010 0.012 0.054 0.000 0.000 0.214
1.995 1.973 1.976 2.141
0.000 0.152
1.889 2.387 2.350 1.853 2.040 3.112
0.019 0.023 0.107 0.000
7.364 1.630
8.046 7.964 7.935 8.045 8.052 7.733
7.500 7.606 7.620 8.115
10.723 3.286
9.238 11.968 11.792 9.135 9.889 14.523
11.158 11.702 12.002 11.185
12c 12d10d 11 12a 12b
0.345 0.3340.262 0.213 0.315 0.246 0.232 0.2740.036 0.067 0.028 0.0570.007 0.097 0.048 0.092
1.988 1.983 1.984 1.9761.908 1.922 1.994 1.9630.110 0.034 0.051 0.0740.128 0.108 0.041 0.0402.395 2.186 2.019 2.0582.318 2.389 2.085 2.2470.722 0.825 1.064 1.0330.822 0.646 0.960 0.7350.071 0.135 0.053 0.1100.013 0.201 0.096 0.1921.901 1.895 1.867 1.8331.871 1.867 1.891 1.8877.910 7.959 7.998 7.9667.976 7.897 7.969 7.939
98.521 98.812 99.256 98.47792.443 98.592 98.724 98.1537.650 7.636 7.613 7.5156.889 7.410 7.635 7.5240.763 0.239 0.352 0.5090.835 0.752 0.281 0.27911.989 10.946 10.077 10.17810.885 11.980 10.381 11.2057.079 8.575 9.934 10.0776.889 7.574 9.367 8.23812.031 12.001 11.783 11.46611.114 11.841 11.910 11.90159.009 59.414 59.499 58.73155.832 59.035 59.150 59.007
CORERIM9c 10a 10b 10c4 8 9a 9b
56141 56141 56141 5614156141 56141 56141 56141
56141 5614156141 56141 56141 56141
CORE RIM
58.642 59.527 59.339 59.128 58.188 53.789
10.979 7.183 7.363 11.497 10.018 13.293
1.804 1.845 1.891 1.794 1.749 0.557
1.241 0.781 0.716 1.308 1.159 1.446
0.044 0.115 0.078 0.030 0.180 1.686
0.301 0.802 0.545 0.204 1.217 10.944
97.817 98.788 98.661 99.264 97.399 97.465
0.396 0.247 0.234 0.414 0.362 0.317
Note: Arrows from rim to core indicates mineral analyses along indivigual crystals transects
28
Appendix 2. Prophyroblastic Systems
Date Collected Location Thin Section Sigma Delta symetrical undetermined6/9/03 26 Katergaki 1691 15 0 16 206/9/03 26 Katergaki 1692 6 0 10 11
6/10/03 31 Katergaki 16101 7 1 2 16/10/03 32 Katergaki 16103 * 11 0 2 26/12/03 38 North Ermopoli 16121 6 13 37 206/12/03 39 North Ermopoli 16122 11 0 22 36/23/03 63 North Ermopoli 36231 8 0 34 36/12/03 39 North Ermopoli 26122a 9 1 13 116/12/03 39 North Ermopoli 16123.1* 17 2 20 56/12/03 39 North Ermopoli 16123.2 7 2 7 146/12/03 39 North Ermopoli 26125 * 2 0 2 66/23/03 63 North Ermopoli 26231 5 0 3 16/13/03 42 Airport 36131 4 1 1 396/13/03 41 Airport 16131 0 0 12 46/13/03 44 Airport 56131 5 3 23 66/13/03 43 Airport 46131 3 0 3 106/14/03 48 Charrasonis Hill 56141 * 0 0 12 126/14/03 45 Charrasonis Hill 16141 0 0 35 206/14/03 47 Charrasonis Hill 36141 8 0 7 76/14/03 47 Charrasonis Hill 36142 0 0 11 46/14/03 48 Charrasonis Hill 46141 1 1 2 66/14/03 48 Charrasonis Hill 56142 3 1 10 36/17/03 50 Perdiki 26171 7 0 2 136/17/03 51 Perdiki 36171 10 2 23 66/19/03 52 Paradice 26191 3 0 14 56/19/03 53 Paradice 36191 0 0 6 126/19/03 52 Paradice 16191 0 2 2 06/20/03 55 San Michael 16203 14 0 5 676/20/03 55 San Michael 16201 16 2 19 156/20/03 55 San Michael 16202 8 0 9 226/21/03 57 Kini 26211 8 0 2 76/21/03 57 Kini 26212 0 0 3 86/21/03 56 Kini 16212 1 8 14 136/21/03 56 Kini 16211 2 8 53 226/22/03 58 Kastri 16221 18 2 13 96/22/03 59 Kastri 26221 1 1 8 76/22/03 59 Kastri 36221 0 5 6 26/23/03 62 Windmill Hill 16231 3 0 3 16/23/03 62 Windmill Hill 16232 0 0 4 0
totals 219 55 470 417Note: * Thin sections analyzed on Smith College's SEM with EDS
Page in Field Notes
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