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J. Zöldföldi, B. Székely:
"Carbon, oxygen and strontium isotopic systematics of Mediterranean white marbles used in the Antiquity";
Poster: EGU 2009, Vienna; 2009-04-19 - 2009-04-24; in: "Geophysical Research Abstracts", 11 (2009), Paper ID EGU2009-1081-1, 1 pages.

Many geological and petrographic systems have been utilized to determine the provenance of classical marble
artefacts. Normally the first steps in sourcing a lithic artefact should be the macroscopic and thin section study with
the petrographic microscope. Unfortunately, often to take sample, which is large enough to make thin section is not
allowed from precious artefacts. A common procedure to analyse powder sample in various ways: The most widely
used system today is that of stable 13C and 18O isotopic signatures. Previous studies showed that, unfortunately,
many quarry fields overlap in values. Because of great advantage of isotopic ratio analysis, principally the need of
only small samples and homogeneity over large areas, we decided to include the 87Sr/86Sr isotopic ratios. Therefore
we tested the 13C, 18O and 87Sr/86Sr isotopic system, based on the data set entry in MissMarble measurement
and information system of marble (Zöldföldi et al. 2008), how fare the system characterises the provenance.
The reason to include Sr is that the Sr contained in carbonate should reflect the composition of seawater at the time
of deposition. Thus the 87Sr/86Sr values found in carbonate rocks will depend largely on the seawater composition
at the original time of deposition. Isotope geochemical studies show that Sr isotopes do not fractionate during
metamorphism.
Thus after initial formation, the principal determinant for oxygen ratios is varying temperatures during metamorphism
and atmospheric weathering; 13C values are depending on the initial organic vs. inorganic material
composition; and strontium by the time of origin and a marine vs. terrestrial source of material. Since each isotopic
variable is determined by different physical factors and each has a different response to later geological history of
the marble, therefore this tree variable make an ideal system for provenancing marble.
13C, 18O and87Sr/86Sr ratios are presented for white marbles collected from some of the most famous classical
quarry areas of the Mediterranean: Hymettos, Paros, Paros-Lychnites, Naxos, Thasos, Pentelikon (Greece), Carrara
(Italy), Afyon, Aphrodisias, Marmara (Turkey), Viana do Alentejo, Vilavicosa (Portugal) and Las Cabreras, Los
Covachos and Macael (Spain).
1017 data pair of 13C and 18O isotopic system and 322 data of 87Sr/86Sr ratios of the above mentioned marble
quarries (Brilli et al. 2005, Attanasio et al. 2006, Morbidelli et al. 2007), including our own measurements, have
been considered in this study. Concerning the Western Mediterranean localities our study is the first to compare
them to Greek, Anatolian and Carrara marbles.
The ranges of the different quarry areas are notably overlapped; this prevents a common adoption of this parameter
in distinguishing the quarry locations for the classification of marbles used for classical architectural and sculptural
artefacts. However some quarry areas show peculiar distributions of their isotopic values, which could help to
assign the provenance to an unknown marble artefact.
Because of the limited number of published Sr isotopic compositions measured on white marbles, it restricts
standalone application, but permits the creation of a widespread database of 15 classical quarries. Unlike the
samples of the Eastern Mediterranean (Anatolia and Greece) the Iberian marbles show different isotopic patterns.
Furthermore the number of samples in this database allows studying the distribution as well. Some sample distributions
show asymmetry that may turn to be important in later studies.
The study confirms that the strontium isotope ratio could be used in marble provenance determination, together
with other methods, as an ancillary technique.

http://publik.tuwien.ac.at/files/PubDat_175600.pdf