Weathering processes on the rock
surface in natural outcrops:
the case of an ancient marble
quarry (Belevi, Turkey)
M. Garcia-Valle
`
s Æ C. Urzı
`
Æ M. Vendrell-Saz
Abstract Weathering and mineralogical processes
observed in a marble quarry in Turkey are com-
pared with similar processes occurring on
monument surfaces. Patina formations (microstro-
matolitic, microlaminated, monolayered) as well as
destructive processes (mainly biopitting and bioe-
rosion) are associated with microbial colonisation of
the rock surfaces and one influenced by microcli-
matic conditions. Patina stratification is indepen-
dent of substrate rock, but is affected by the position
and orientation of rock surfaces. The different layers
formed by mineralisation processes may reflect the
seasonality of climatic events and the consequent
colonisation. Bio-deteriorative processes take place
mainly when the climatic conditions cause the
organisms to live below the surface.
Keywords Bioactivity Æ Marble weathering Æ New
minerals Æ Outcrops Æ Patina
Introduction
Rock surfaces modify their aspect in natural outcrops,
depending on the interaction processes between atmo-
sphere and rock. Weathering processes lead to changes in
rock surfaces from the very beginning of their exposition
in the open air whether they are natural outcrops or
buildings. In nature, changes in the rock are the result of
different chemical, physical and biological factors, which
lead to the production of (bio)-minerals (deposition) and/
or to erosive processes that are constructive or destructive
phenomena, respectively. The rate at which the processes
takes place is a function of several factors, including the
intrinsic properties of the rock.
Some authors have related these interactive processes be-
tween rock and environmental factors with global climatic
dynamics. A climatic shift of the so-called ‘Little Ice Age’
was documented in the Mediterranean area between 1830
and 1870, which provoked intense rainfall, cold winters and
humid air (Barriendos-Vallve and Martin-Vide 1988).
Other climatic events have also been documented by geo-
logical studies (James 1972; Semeniuk and Searle 1985;
De Villiers 1990; Howell et al. 1990; Stewart et al. 1990;
Vandenberghe 1992; Baker et al. 1993, 1999; Dorn 1994; Russ
et al. 1996; Garcia-Valle
`
s et al. 1998). In fact, the record of
growth of carbonate deposits is a potential indirect mea-
sure of climatic change of continents (Baker et al. 1993).
Thus, crusts that have formed on the rock surfaces contain
interesting palaeo-environmental information (Krumbein
1968; Krumbein and Jens 1981), which allows the identi-
fication of local or global climatic shifts of different
intensity and duration at the microscale level.
Events comparable with those observed in natural outcrops
are also evident in man-made surfaces such as buildings
and quarries. In fact, in natural outcrops, but especially in
quarries, we can observe geometrical features (namely
vertical walls and more or less sheltered areas), environ-
mental conditions (rainfalls, sun exposure) and biological
processes similar to those found in monuments. Patina
development is quite similar to that found on monuments
(Bernardi et al. 1985; Jones 1989; Garcia-Valle
`
s et al. 1996a,
1996b; Bla
´
zquez et al. 1997; Urzı
`
et al. 1999). Therefore, it is
expected that studies carried out on patinas/crusts on
natural outcrops could be extrapolated to provide a better
understanding of deterioration of monuments.
The present research had three main aims:
1. To analyse patinas developed under different micro-
environmental conditions;
2. To correlate them with the biological factors involved in
patina formation;
3. To explain the formation of ancient patina correlated
with the processes induced by recent bioactivity.
Received: 8 March 2001 / Accepted: 2 November 2001
Published online: 22 January 2002
ª Springer-Verlag 2002
M. Garcia-Valle
`
s(&) Æ M. Vendrell-Saz
Department of Crystallography,
Mineralogy and Mineral Deposits,
University of Barcelona, c/ Martı
´
i Franque
`
s,
s/n, 08028 Barcelona, Spain
E-mail: mtgarcia@natura.geo.ub.es
Tel.: +34-93-4021348
Fax: +34-93-4021340
C. Urzı
`
Department of Microbiological,
Genetic and Molecular Sciences,
University of Messina,
Italy. Salita Sperone, 31, 98166 Messina, Spain
Original article
DOI 10.1007/s00254-001-0466-y Environmental Geology (2002) 41:889–897
889