ISSN 1754-1026
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No 1 - Jun 2007
Newsletter on stone decay
Contents:
Foreword:
Pg 2
Article:
Malta's prehistoric temples: conservation issues
J. Cassar
Pg 3
Young researchers:
Study and characterization of protective patinas from the architectural
heritage
C. Vazquez-Calvo
Pg 8
Provenance determination of marbles from the Czech Republic
A. Šastná
Pg 10
Characterization of mortars from archaeological sites
E. Galea
Pg 11
Mortars and plasters used in building conservation - A study of the
local scenario
G. Drago
Pg 13
Replacement or plastic repair: A discussion on current local
restoration philosophy
D. Zahra
Pg 15
Recording weathering and decay
Pg 18
Ongoing and newly funded projects
Pg 20
News:
Pg 22
Edited by::
Weathering Research Group
School of Geography, Archaeology and Palaeoecology
Queen’s University of Belfast
Contact and Submissions :
M. Gomez-Heras
m.gomez@qub.ac.uk
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Foreword:
This newsletter is a response to the wish expressed at several scientific meetings during recent
years for a flexible means of communication between those who work in the field of stone
weathering.
This newsletter does not, however, intend to be another journal among the overwhelming multitude
of scientific journals that nowadays publish papers on stone weathering. Instead, it aims to create
an informal vehicle of expression that will go further than just the reporting of scientific results.
We present this first issue in the SWAPNET meeting held in Malta, 2007. This is because it is hoped
that the newsletter will share the spirit that has characterized the SWAPNET meeting throughout
the years, and will focus especially on “work in progress” without the necessity of having to report
only “definitive results”.
It is also hoped that, in providing updated information on ongoing research projects by groups, it will
help prevent duplication of research and promote synergies. Especially because of the need for
these at a time when research into stone weathering faces new challenges in response to changing
climates that will modify also the weathering environment.
This newsletter will not, however, accomplish its mission if it exists merely as a passive notice
board. We would like it to contain opinion articles, interviews, information on ongoing projects,
collaboration opportunities and everything that will serve to strengthen the links between research
groups.
In particular, a crucial part of this newsletter will be the contribution of PhD students and the
opportunity it will provide to publicize how progress on their research is going, and to provide a
finger on the pulse of the research being carried out in their laboratories.
The layout of this first issue is provisional and inevitably it will evolve and change, as more of you
contribute, send material and provide new ideas.
We hope that through this newsletter, the flow of communication between research groups will
increase and that this will be useful in strengthening the outcomes of our endeavours.
MGH & BJS
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Malta's prehistoric temples: conservation issues
J. Cassar
Abstract
Malta's prehistoric megalithic temples, which are World Heritage sites, are currently suffering from problems
associated with the deterioration of materials as well as structural problems. These problems have been studied for
many years. A Scientific Committee set up by the Government of Malta in 2000, identified those elements in the
surrounding environment causing deterioration of the site. It was recommended that the sites should be protected by
temporary shelters, which would provide additional time for research into the long-term preservation of these sites.
The sheltering project should kick off late in 2007. In preparation, Heritage Malta has been since 2005, and is still
currently, intensively studying the temples as well as conditions in and around the site. Much of this information has
already been fed into the final detailing of the shelters. The data obtained from the environmental monitoring in
particular will also constitute important baseline information which will then be used to compare with the altered
conditions under the shelters.
Introduction
Malta's prehistoric megalithic temples, dating to the
period ca 3600 2400 BC are World Heritage sites.
The temples include those of Mnajdra and Hagar
Qim (Figure 1), Tarxien, Skorba and Ta' Hagrat on the
island of Malta, and Ggantija, on the island of Gozo.
Since 2003, Malta's prehistoric temples have
been managed by Heritage Malta, a Government
Agency whose principal mission, as defined in the
Cultural Heritage Act 2002, is to ensure that those
elements of Malta’s cultural heritage entrusted to it
are protected and made accessible to the public.
These sites were formerly under the care of the
Museums Department. Both of the two locally
available limestones, the Globigerina Limestone and
Figure 1: Temple complex of Hagar Qim (Heritage Malta).
the Coralline Limestone, were used in the
construction of the megalithic temples. Hagar Qim
and Tarxien are built entirely of Globigerina
Limestone. At Ggantija, on the other hand, very little
use was made of Globigerina Limestone, and
practically the entire complex is built of Coralline
Limestone outcropping nearby. In the case of
Mnajdra, Coralline Limestone was used for the
construction of some of the external walls
whereas Globigerina Limestone was used for the
internal walls. Decorative elements occur in most of
these sites and include altars, animal reliefs and spiral
motifs; these are also carved out of the soft
Globigerina Limestone. All of these temples are
currently suffering, to a greater or lesser extent, from
a number of problems, including those associated
with the deterioration of materials as well as
structural problems, including a number of serious
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collapses which occurred in recent years. Studies
have been ongoing for many years to understand the
state of conservation of these temples, and the nature
and extent of deterioration, as well as to identify the
causes of these problems.
Past studies
Within the framework of a multi-disciplinary joint
project between the (then) Museums Department,
Malta, and the University of Florence, Italy, the
megalithic monuments of Ggantija, Hagar Qim and
Tarxien were studied over a period of 7 years (1985 to
1991). Studies of the materials were carried out on
approximately 100 samples, judiciously obtained
from the stone surfaces and a few by core drilling.
The majority of the samples were Globigerina
Limestone, but some Coralline Limestone megaliths
were also studied. Analyses included mineralogy
(identification of main minerals, insoluble residues
4
and clay fractions), petrography (preparation and
examination of thin sections), chemical composition
(including soluble salts), physical properties
(evaluation of total porosity, pore size distribution
and water absorption) and micro-structural studies.
Structural problems affecting these ancient structures
were documented and assessed by means of
planimetric and structural surveys, both direct and by
photogrammetry. Also included were detailed
mapping of the façade of the temple of Ggantija, as
well as plans and elevations of all the temples under
study, i.e. Ggantija, Hagar Qim and Tarxien.
Action
The first concrete steps taken towards the
preservation of these temples included the setting up
of a Scientific Committee by the Government of
Malta in 2000. This followed from the
recommendations of an International Experts Group
Figure 2: The two temple sites of Hagar Qim and Mnajdra (Heritage Malta).
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meeting in Malta on the Conservation of Malta's
Megalithic Temples, held in May 1999. The remit of
this Scientific Committee was to study and give
advice on possible conservation solutions for the
preservation of the temples.
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would moreover provide additional time for a deeper
understanding of the effects the combination of these
factors has on the temples, and will gain time to allow
for research into the long-term preservation of these
sites.
Following a Cabinet decision in August 2000, an
international competition for the design of shelters
for the sites Hagar Qim and Mnajdra (Figures 2 and
3), considered to be amongst the most fragile of the
temple sites, was launched, under the auspices of the
International Union of Architects (IUA) in 2003. 3.5
million Euros of funding was secured through the
European Regional Development Fund, and the
endorsement of the UNESCO World Heritage
Committee was gained. The sheltering project should
kick off late in 2007 and aims at protecting these sites
for a period of between 25 -30 years. These shelters
are intended as an interim measure while research
continues in order to identify less visually intrusive
alternatives.
In preparation for the building of these shelters,
Heritage Malta has been since 2005, and is still
currently, intensively studying the temples as well as
conditions in and around the site. These studies
include environmental monitoring, thermographic
measurements, further stone sampling and analysis,
measurements of water runoff, sampling and
analyses of biological aerosol and atmospheric
Figure 3: Model of the shelter to be constructed over
the Hagar Qim temple (Walter Hunziker / Michael
Kiefer).
The remit of this Scientific Committee was to study
and give advice on possible conservation solutions
for the preservation of the temples. The Committee
identified elements in the surrounding environment
as the main causes of deterioration of the site. These
were acknowledged as being rain, wind (speed and
direction), air temperature and relative humidity,
solar radiation, and pollution, including also sea salt
aerosol, Sahara dust, SO2, NOx and volcanic
emissions, as well as biological organisms.
It was then recommended that the sites should be
protected as far as possible from the effects of these
adverse conditions. Shelters were proposed as being
the most suitable, reversible but temporary means of
protecting these ancient and fragile sites from these
harsh external influences. These temporary shelters
Figure 4: Hagar Qim temple autumn-winter wind
chart, 2005 (Heritage Malta).
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aerosol, and 3-D scanning of both sites and the
surrounding terrain. much of this information has
already been fed into the final detailing of the
shelters. The data obtained from the environmental
monitoring in particular will also constitute
important baseline information which will then be
used to compare with the altered conditions under the
shelters. This continuous monitoring is to be shortly
intensified, with additional information to be
collected from inside the temples, and will continue
even after the shelters have been installed. Postsheltering data will then be comparable with data
gathered before, the interpretation of which should
give a deeper understanding of the complex
deterioration mechanisms brought about by a
combination of the factors as already mentioned
above.
Environmental monitoring is being carried out by
Heritage Malta staff, in collaboration with the Istituto
di Scienza dell'Atmosfera e del Clima CNR ISAC
Bologna Italy, and is being funded by the 2003 EU
Pre-Accession funding programme. This monitoring
is being achieved by means of a meteorological
automatic station operating at Hagar Qim, recording
air temperature, relative humidity, solar radiation,
wind direction (Figure 4) and speed and rainfall.
Thermal image
29th June 2005 at 11.30 am
Micrometeorological measurements are also being
collected by means of two automatic stations also
installed at Hagar Qim and Mnajdra. Surface
monitoring includes air and surface temperatures,
relative and specific humidity and time of wetness as
well as dew point of the air.
Thermal Infrared measurements (Figure 5) have also
been performed on the surfaces of the megaliths,
using a thermal camera to monitor the heating of the
stone surface. Thermographic measurements also
allow for the evaluation of whether the surface
conditions are subject to water condensation or
evaporation.
Sampling of the stone surface has also been carried
out to confirm and supplement previous studies on
damage evaluation and the identification of natural
and anthropogenic causes of deterioration. This is
being done once again by analyses of soluble salts.
Other parameters are also being measured. These
include water runoff, to measure liquid and solid
runoff in specific vulnerable areas; an evaluation of
surfaces exposed to erosion or deposition of soil; and
water level measurements, since in some areas of the
temples flooding occurs after heavy or continuous
precipitation. These studies are being supplemented
Thermal image
29th June 2005 at 3.30 pm
Figure 5: Thermal images of part of the Hagar Qim external wall (Heritage Malta).
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by short environmental campaigns which include the
sampling and analyses of biological and atmospheric
aerosols; morphological investigations of aerosol
particles are also being made.
3-D scanning and modeling of both sites has been
carried out by A.B.C. Appalti Bonifiche Costruzioni
of Firenze Italy. The principal objective has been to
carry out high-definition 3-D documentation of the
sites, and the end product was a 3-D digital model of
each of the two temple complexes and the
surrounding terrain. This has now created a highquality base-line record of the present state of the
megalithic structures.
Conclusion
The decision to shelter these unique but fragile World
Heritage sites is a bold step which, however, was not
taken lightly. It is bases on previous studies, deep
background knowledge and also grave concern
following a perceived acceleration in the
deterioration of these sites. In full knowledge of
Malta's international responsibilities, prolonged
studies and continuous monitoring of the sites and
their environment is being carried out in
collaboration with respected international experts in
the field. These should ensure that the shelters fulfil
their aims of protecting these ancient structures
whilst at the same time buying time to carry out the
necessary research for the long term preservation of
these unique sites.
Acknowledgements
References
1993. Pieri Nerli P., and Zetti I. “I templi preistorici megalitici
maltesi. Studi e proposte di intervento conservativo per i
complessi di Ggantija e Hagar Qim. Tesi di Laurea in
Architettura” (unpublished). Facolta' di Architettura,
Dipartimento di Storia dell'Architettura e Restauro delle
Strutture Architettoniche, Universita' degli Studi di Firenze,
Italy.
1994. Tampone G., Vannucci S., Ferri W., Cassar J., Fiorito S.,
Pieri-Nerli P., Sausa P., and Zetti I. "I templi megalitici
preistorici delleisole maltesi: la rilevazione architettonica". In:
Proceedings of the 3 rd International Symposium, The
Conservation of Monuments in the Mediterranean Basin,
Venice, Italy, 443 453.
1994. Vannucci S., Alessandrini G., Cassar J., Tampone G., and
Vannucci M.L. "I templi megalitici preistorici delle isole
maltesi: cause e processi di degradazione del Globigerina
Limestone". In: Proceedings of the 3 rd International
Symposium, The Conservation of Monuments in the
Mediterranean Basin, Venice, Italy, 555 565.
1996. Vannucci M.L. “Studio mineralogico-petrografico delle
“pietre” dei templi preistorici dell'arcipelago maltese e relativi
prblemi conservativi. Tesi di Laurea” (unpublished), Facolta' di
Scienze Matematiche, Fisiche e Naturali, Universita' degli Studi
di Firenze, Italy. Corso di Laurea in Scienze Geologiche.
2001. Cassar J., and Vannucci S. “Petrographical and chemical
research on the stone of the megalithic temples.” In: Malta
Archaeological Review, Issue 5, 40- 45.
2003. Stroud K. "The Conservation of the Temples of Hagar
Qim and Mnajdra", unpublished M.A. dissertation, University
of Malta.
2003. Hunziker W. “Hagar Qim und Mnajdra Heritage Park,
Malta”.
Specifier,
Issue no. 59.
2004. Hunziker W. “Hagar Qim und Mnajdra Heritage Park,
Malta”. The Architect, Issue no. 29.
A.B.C. Appalti Bonifiche Costruzioni Firenze Italy
European Regional Development Fund and EU Pre-Accession
funding programme
Heritage Malta
International Union of Architects (IUA)
2005 2006. CNR-ISAC. Environmental Monitoring at Hagar
Qim and Mnajdra Temples. Four Quarterly Reports and Interim
Report. Unpublished reports.
2006. CNR-ISAC. Environmental Monitoring at Hagar Qim
and Mnajdra Temples. Results and Recommendations on the
microenvironmental impact of the shelters for the Temples.
Unpublished report.
ICCROM, Rome and Zaki Azlan
Istituto di Scienza dell'Atmosfera e del Clima CNR ISAC
Bologna Italy
UNESCO World Heritage Committee
University of Florence, Dipartimento di Storia dell'Architettura
and Dipartimento di Mineralogia, Petrografia e Geochemica,
Florence, Italy
Walter Hunziker / Michael Kiefer.
2007. Dietsche D. “Formfindung fûr eine membrane”. Tec-21,
Nr 1-2.
J. Cassar: joann.cassar@um.edu.mt
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Study and characterization of protective patinas from the architectural heritage
C. Vazquez-Calvo
(Supervised by Dr R. Fort & Dr M. Alvarez de Buergo)
Instituto de Geologia Economica (CSIC-UCM), Madrid, Spain.
This PhD project is being carried out at the Instituto
de Geología Económica in Madrid, a research
institute funded jointly by the Spanish Council for
Scientific Research and the Complutense University
of Madrid supervised together by Rafael Fort
González and Mónica Álvarez de Buergo. This
thesis is part of one of the main research lines of the
Heritage Conservation Group, as well as the national
funded project, just ended, entitled 'Design of
protective patinas in stony materials from Building
Heritage'. The thesis aims to characterize the patinas
of different monuments from the Spanish central area
and to establish their composition for their further
reproduction.
Several studies have been developed on 'patinas'
since Liebig characterised for the first time the
mineral that he named as 'thierschite', and that later
on was nominated whewhellite (calcium oxalate)
discovered in the Parthenon. These studies have been
carried out mainly in Italy and Greece and many of
them are published in Italian. The first objective of
the research was to compile all this information in
order to get an overview of the theories and studies
developed until the moment. From the beginning, she
realised that there were two main hypotheses, one of
them defended the biological origin of the patina and
the other the artificial genesis due to ancient
protective treatments, although the last studies claim
favourably for the artificial origin without neglecting
a possible biological activity. Plus this fact, there was
also different terminology to refer to the same kind of
material like patina, layer, oxalate film, etc.
However, all of them have common characteristics as
they present different colouration than the substrate
(brown, orange, pink) and in most of the cases a
common mineralogy (calcium oxalates, calcium
phosphates, clay minerals, etc). With this
background, she began to characterise patinas from
buildings from the central area of Spanish in order to
establish their composition and preservation state
and trying to proof their artificial origin by means of
different techniques. Buildings from 15th to 17th
century located in different provinces of the area
were chosen. This variability, in time and space,
made her possible to take into account possible
variations of the patinas due to geographic or
historical facts.
Figure 1: Photography of 'Palacio del Infantado'
(Guadalajara, Spain) with a detail of the patina (brown
sample) and its thin section view under polarized light
microscopy.
At the same time, a collection of ancient recipes was
made. With the results obtained up to now and the
information got from the recipes, 32 different
mixtures were prepared using lime, casein, egg, milk,
blood, among other ingredients, and applied on
limestones. After keeping these samples outwards in
an urban area, the studies reveal at the present stage
that the petrographic properties of some of the
artificial patinas obtained are quite similar to those of
the ancient ones.
The knowledge of this building technology could
create a social awareness about the preservation of
the patinas during future restoration works.
Other important point of the research was the
assessment of the use of non-destructive techniques.
When working with Heritage, sampling must be
limited in number and samples dimension. For this
reason and in collaboration with Centro Nacional de
Aceleradores (CSIC) and under the supervision of
Dr. Blanca Gómez Tubio a study of the use of Energy
Dispersive X-Ray Fluorescence Spectrometer was
carried out. Since laser based techniques are also very
suitable a study of the application of Laser Induced
Breakdown Spectroscopy (LIBS) was also made
through the scientific collaboration with Dr.
Demetrios Anglos from 'Institute of Electronic
Structure and Laser' IESL-FORTH (Crete, Greece)
and financed by a Marie Curie Fellowship.
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Both non-destructive and portable equipments will
provide the possibility of partially characterising the
patina at the monument in the future.
Among the works that have resulted from the
research, the following ones could stand out:
Vazquez-Calvo C., Alvarez De Buergo, M., Fort, R. (2006).
Patinas in the Architectural Heritage of Lerma, Burgos (Spain).
In: Heritage, Weathering and Conservation (ed. R. Fort, M.
Álvarez de Buergo, M. Gómez-Heras, C. Vázquez-Calvo).
Taylor & Francis/Balkema, London, 2, 969-974.
Vazquez-Calvo, C., Alvarez De Buergo, M., Fort, R., (2007)
Overview of recent knowledge of patinas on stone monuments:
the spanish experience, In: Building Stone Decay: From
9
Diagnosis to Conservation (ed. R. Prikryl y B.J. Smith).
Geological Society, London, Special Publications, 271, 295307.
Vazquez-Calvo, C., Giakoumaki, A., Anglos, D., Álvarez De
Buergo, M., Fort, R. (In press) Classification of patinas found on
surfaces of historical buildings by means of Laser Induced
Breakdown Spectroscopy. In: Laser in the Conservation of
Artworks LACONA VI Proceedings (ed. J. Nimmrichter, W.
Kautek, M. Schreiner). Springer Proceedings in Physics,
Dordrecht (The Netherlands) Vol. 116.
Vazquez-Calvo, C., Alvarez De Buergo, M.,Fort, R., Varas, M.J.
(In press) Characterization of patinas by means of microscopic
techniques. Materials Characterization.
C. Vazquez-Calvo: carmenvazquez@geo.ucm.es
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10
Provenance determination of marbles from the Czech Republic
A. Šastná
(Supervised by Dr R. Pøikryl)
Inst. of Geochemistry, Mineralogy and Mineral Resources, Fac. of Science, Charles University in Prague, Czech Republic
Current PhD project is focused on the provenance
determination of marbles from Czech quarries. The
main purpose of this pilot study is to compile
petrographic, geochemical and physical data for
distinction between different types of marbles. It is
also aimed to explore suitability and limits of
experimental techniques for provenance studies. The
results have implications for a future possible
comparison of samples with historical artefacts and
will be part of the Czech database of dimension
stones.
Determination of the source locality of marbles
represents difficult task due to variable composition
(mineralogical, chemical) of the rocks coming from
one locality and similarity between samples from
different areas. In particular, there is no universal
method suitable for recognition of marbles. Most of
the studies therefore rely on the combination of
several analytical techniques (compare e.g. Craig and
Craig 1972; Herz 1985; Barbin et al. 1992). The most
widely used procedure for the identifications of
marbles combines petrographic examination, C-O
stable isotope analyses and/or cathodoluminescence
study (Lapuente et al. 1998, 2000; Gorgoni et al.
1998). Most of the previous analytical studies on
marble provenance have been conducted on pure
calcitic marbles from Mediterranean. Czech
Republic is rich in “impure” calcitic or
calcite/dolomitic marbles containing common noncarbonate minerals (mostly silicates) or organic
matter that was transformed to the carbonaceous
matter during metamorphosis. This specific
composition lead to the introduction of some
techniques that have not been used for marble
provenance studies before (e.g. Raman
microspectrometry or physical properties like
magnetic susceptibility).
The plan of the PhD thesis includes several
successive steps. First of all, the complete
background research about Czech quarries was done.
Furthermore, samples were collected in terms of the
Atlas of dimension stones project (Pøikryl et al.
2001). Analytical techniques were chosen on the
basis of white marbles studies from the
Mediterranean area but some less conventional
methods were applied as well due to different
chemical and physical characteristics of Czech
marbles. In this study, mineralogical-petrographic
and geochemical methods have been tested i.e.:
optical microscopy of the whole rock, petrographic
image analysis of carbonate grains, X-ray diffraction
of the insoluble residuals, Raman microspectrometry
of the carbonaceous matter of “graphitic” marbles,
stable isotope ratio analysis of carbonates in
groundmass and secondary veins,
cathodoluminescence of microfacies and magnetic
susceptibility of the whole rock. In conclusion, data
obtained from the analysis of marbles from quarries
can be used of the sourcing of materials used at the
monuments and artifacts. Development of specific
methodology of the study of “impure” marbles
represents another important output of this PhD
project.
References
Barbin V., Ramseyer K., Decrouez D., Burns S. J., Chamay J.,
Maier J. L. (1992): Cathodoluminescence of White Marbles: an
Overview. Archaeometry, 34(2): 175-183.
Craig H., Craig V. (1972): Greek Marbles: Determination of
Provenance by Isotopic Analysis. Science, 176: 401-403.
Gorgoni C., Lazzarini L., Pallante P., Turi B. (1998): An updated
and detailed mineropetrographic and C-O stable isotopic
reference database for the main Mediterranean marbles used in
antiquity. In: Hermann J. J., Jr., Herz N., Newman R. (ed.)
Interdisciplinary studies on ancient stone. Asmosia 5, Museum
of Fine Arts, Boston, 115-131.
Herz N. (1985): Isotopic Analysis of Marble. In: Rapp G., Jr. and
Gifford J. A. (ed.) Archeological Geology. Yale University
Press, New Haven and London, 331-351.
Lapuente M. P., Martinez M. P., Turi B., Blanc P. (1998):
Characterization of dolomitic marbles from the Malaga
Province (Spain). In: Hermann J. J., Jr., Herz N., Newman R.
(ed.) Interdisciplinary studies on ancient stone. Asmosia 5,
Museum of Fine Arts, Boston, pp. 152-162.
Lapuente M. P., Turi B., Blanc P. (2000): Marbles from Roman
Hispania: stable isotope and cathodoluminescence
characterization. Applied Geochemistry, 15: 1469-1493.
Pøikryl R., Svobodová J., Siegl P. (2001): Search for historical
resources of dimension stone in the Czech Republic. In:
Sandrone R. (ed.) Proceedings of the International workshop
“Dimension stones of the European mountains”, June 10-12,
2001, Luserna san Giovanni Torre Pellice (Italy), pp. 307-309.
A. Šastná: astastna@gmail.com
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Elizabeth Galea, Glynn Drago and David Zahra are carrying out their MSc research project at the Institute for
Masonry and Construction Research, University of Malta. The Institute runs a postgraduate course on Conservation
Technology for Masonry Buildings. Its research areas include the study of archaeological and historical mortars,
within which areas of study two of these research projects fall. These are the first two studies on mortars carried out
within the Institute; other areas of research include the characterisation of durability of Globigerina Limestone,
Coralline Limestone in Maltese buildings and restoration philosophies. It is within the latter field of research that
the third study falls.
Characterization of mortars from archaeological sites
E. Galea
(Supervised by Dr J. Cassar)
Institute for Masonry and Construction Research, University of Malta
'Ancient mortars are valuable evidence on old
masonry techniques'. (Jedrzjewska, 1981)
To date, most research work locally has been carried
out on historical mortars and little information is
available on mortars and plasters present in
archaeological sites. Malta's archaeological heritage
extends from its first colonized caves (the oldest,
Ghar Dalam, dating to 5000 B.C.) to its prehistoric
temples (3500 B.C.) to its Roman remains and ruins
(dated around 500 B.C. to 400 A.D.) (Trump, 2004)
to medieval architecture and artefacts (800 A.D. and
later) (Bonanno, 2005). The scientific study of the
materials present in these sites will serve as a detailed
documentation of the archaeological heritage of the
Islands, while providing valuable information for the
eventual conservation of each site.
Intermediary Painted
Plaster Indicating Two
Distinct Periods of Time
Figure 1: Intermediary Painted Plaster at Ghajn Tuffieha
Roman Baths 50-150A.D.
Figure 2: Wall Lining at Zejtun Roman Villa possibly
300A.D.
Scientists and archaeologists are interested in this
archaeological evidence for different reasons: the
former to understand manufacturing techniques and
other technical information relating to previous eras,
whilst the latter can use the information to contribute
towards the chronological classification of samples
without a context (Jedrzjewska, 1981). This
dissertation will investigate a number of samples
from several sites quantitatively and qualitatively in
order to start building a database which could help
scientists and archaeologists alike in the historical
interpretation of the site, or other local sites, by
facilitating dating and authentication of the area
under study. Samples will be examined for their
visual, mechanical, physical, chemical and
mineralogical properties using analytical techniques
such as microscopy, SEM/EDS, XRD, chemical
testing, thermal and infra-red imaging as well as
other available techniques which may become
necessary as the research develops.
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At present, the study is in its preliminary stages,
focusing primarily on a broad literature review in
order to understand the research that has been carried
out in other countries. Results from Maltese sites will
then be discussed in view of the research carried out
elsewhere to determine how Malta fits in the general
picture. So far, similar studies have been carried out
in most Mediterranean and North Eastern European
countries as well as on archaeological sites in the
Middle East (e.g. Jordan). This research already
indicates the results which may be expected within
the local scenario. In addition, this review allows for
a detailed evaluation of the range of analytical
techniques and methodologies that have been
previously applied, information which falls directly
within the scope of this dissertation.
Since the local archaeological sites extend over such
a long period of time and samples for each era are
available, it has been decided to focus the study on
one particular period, to be decided in consultation
12
with local archaeologists. Through visual, physical
and chemical characterization, archaeological data
and comparison of samples, it is being anticipated
'that enough information will be available for the
construction of a database. This database will help
archaeologists to determine type and chronology of
mortar samples that are found within rubble mounds
with no archaeological context as is the case in many
excavations.
In conclusion, the work done will lay the ground for
future developments and research. This may include
further characterization of mortars and studies of
techniques from different periods and hence the
expansion of the suggested database, as well as the
examination of information retrieved from the
collected data with respect to historical information,
and the identification and eventually the design of
compatible mortars for the future conservation of
these sites.
Figure 4: Similar Plaster and Mosaic Floor Samples
without Context held by Malta Superintendence for
Cultural Heritage from Mdina Excavations.
Bonanno, A., 2005. Malta Phoenician, Punic, and Roman
Malta: Midesea Books Ltd.
Figure 3: Similar Mosaic Flooring and Mortar Bedding
from the multicultural Tas-Silg Sanctuary and the Domus
Romana 125-75B.C. - Marble Tesserae in a 'cocciopesto'
like Matrix.
Jedrzjewska, H., 1982. Ancient Mortars as Criterion Analyses
of Old Architecture In: Mortars, Cements and Grouts used in the
Conservation of Historic Buildings Symposium 3 6.11.1981.
Rome: ICCROM pp.311-329.
Trump, D.H., 2004. Malta Prehistory and Temples 2nd ed.
Malta: Midsea Books Ltd.
E. Galea: elizabeth.galea@gov.mt
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13
Mortars and plasters used in building conservation - a study of the local scenario
G. Drago
(Supervised by Dr J. Cassar)
Institute for Masonry and Construction Research, University of Malta
In the conservation of stone masonry buildings,
mortars and plasters are generally defined as
“sacrificial materials”. In other words, such
components should deteriorate in preference to the
actual building blocks within the masonry structure.
Furthermore these materials also contribute towards
the aesthetic value of a building, allow mobilisation
of moisture and soluble salts within them, protecting
the masonry blocks by producing a barrier to the
exterior, and allowing structural movements to occur
within them rather than damaging the blocks
themselves.
blends of either locally produced air-lime, or
imported hydraulic limes, which are mixed with
sands (Coralline Limestone sand, and Globigerina
Limestone dust).
The above descriptions seem to embody a universal
definition of how a good mortar or plaster should
perform. Nevertheless, a particular mortar or plaster
mix may be excellent for one particular situation, yet
disastrous for another.
Even though some local studies have been carried out
in the past, much work is still needed in this field. In
the absence of such research, Maltese conservation
professionals tend to use their acquired knowledge
from past experience and also foreign literature, to
produce what they believe are the best possible mixes
suited for local conservation purposes. Nonetheless,
although one would assume that there is a general
tendency to improve on experiences of the past, there
has not been any attempt to co-ordinate the results of
different individuals or entities and analyse what they
are specifying. This lacuna of information has
inspired the need for the research being hereby
described.
During the last decade in particular, many
developments have occurred in the local sphere of
conservation. As a result, various mortar and plaster
mixes are currently being used in both public and
private sector projects. This research has hence
commenced by investigating the variation of mix
binders aggregates and additives used in local
conservation mixes and the common mix proportions
on the basis of which these are applied. Furthermore,
the main additives which seem to be in use are
crushed pottery and marble dust. This information
was derived by discussion with local stakeholders
involved in building conservation projects. It is now
evident that most of these mixes are mainly based on
Figure 1: Munsell colour notation - sample colour
comparisons (moist state).
Moreover, a number of imported proprietary mixes
have also been identified in this exercise. Given the
limited local market, there seem to be only a handful
of such available products. Such mixes vary from
premixed aggregate/hydraulic lime mixes, to what
are defined as macro-porous plasters. What is of
concern is that these products were produced for a
foreign scenario, were never tested locally, and more
often than not their technical literature fails to
mention their exact ingredients due to industrial
secrecy.
Once the above information was complied, the author
short-listed these mixes into twelve test mixes which
would be used as representative mixes of the Maltese
conservation mixes. At this point, all materials
necessary for the replication of such mixes were
obtained, and a testing programme was set up to
evaluate the performance of the test mixes in relation
to the properties which make them a good
conservation mortar or plaster. Wherever possible,
testing procedures were undertaken according to
international testing standards such as UNI, EN and
NORMAL. The programme involved the following
tests:
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14
9
Eventually this programme should give the author
the capability to draw certain conclusions on the
validity of the currently locally used conservation
mortars and plasters, including compatibility of these
mixes with the local substrate. By comparing the
acquired data to that of local Globigerina Limestone,
and considering the local conditions, one may then
suggest possible improvements (if necessary), to
such mixes or else shed light on the way forward
towards further future research.
Figure 2: Determination of Total Porosity (Left)
Quantachrome helium gas pycnometer apparatus. (Right)
Cylindrical mix samples prepared for testing.
1. Testing in the “Fresh” State: Consistency and Bulk
Density.
2. Mechanical Strength Tests: Flexural Strength,
Compressive Strength.
3. Aesthetic Properties: Colour Consistency, Mortar
Staining of Stone.
4. Physical properties: Total Porosity, Water
Absorption, Water absorption by capillary action.
5. Salt Content Tests: Conductivity Tests and Ion
Chromatography.
6. Salt Resistance tests: Resistance to Sodium
Sulphate and Sodium Chloride.
Bibliography
Ashurst, J. & Ashurst, N. (2003). Practical Building
Conservation Mortars, Plasters & Renders, Volume 3, Ashgate
Publishing Ltd, England.
Bosiljkov V.(2001), The use of industrial and traditional limes
for lime mortars, University of Ljubljana, Faculty of Civil and
Geodetic Engineering, Slovenia, In: Historical Constructions Possibilities of numerical and experimental techniques. Proc.
3rd Int. Seminar on Historical Constructions (Eds. P.B.
Lourenco and P. Roca), University of Minho, Guimaraes,
Portugal, 2001, pp.343-352.
Cachia, D. (1995), Lime-Based Mortars for the Repair of
Ancient Monuments, University of Malta, B.E.&A. (Hons.),
Dissertation (unpublished).
Farray M., There is more to lime mortar than …, Context, Issue
52, 1996, page 26.
ICCROM (1981) Mortars, Cements and Grouts used in the
Conservation of Historic Buildings - Symposium 3-6.11.1981,
Rome.
Torraca, G. (1982) Porous Building Materials Material Science
for Architectural Conservation, ICCROM, Rome.
US/ICOMOS (2001) Historic Mortars & Acidic Deposition on
Stone, US/ICOMOS Scientific Journal Volume 3, Number 1
2001.
Van Hees R. (2004) Compatibility of plasters and renders with
salt loaded substrates in historical buildings, 5th EC Conference
May 16-18 2004, Institute of Catalysts and Surface Chemistry,
Polish Academy of Sciences.
G. Drago: glynndrago@yahoo.co.uk
Figure 3: Tests for Resistance to Sodium Sulphate
Deterioration (Left) Mix Samples being soaked in a 14%
Sodium Sulphate solution prior to Drying. (Right) Sample
Mix 1.01 (Air-Lime and sand 1:3), prior to testing (Cycle
0), and on failure (Cycle 2).
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15
Replacement or plastic repair: A discussion on current local restoration philosophy
D. Zahra
(Supervised by Arch K. Buhagiar)
Institute for Masonry and Construction Research, University of Malta
'Historic' - 'Aesthetic'
Abstract
There is no recipe book or methodology or charter or
philosophy that spells out when and how to intervene
on the historic fabric, one reason being that each
building can and should be treated as an individual
case. Furthermore, international guidelines and
charters do not necessarily address the particular
issues and problems characteristic of the local built
heritage, in the Maltese context the (lime) stone
fabric.
By analysing the current local restoration industry,
from a philosophical, ethical, practical and economic
point of view, contrasted with charters and current
(contemporary) thinking, this research is aimed at
understanding the (local) 'scenario' within which
restoration projects are carried out. Through
administering a questionnaire (designed by the
researcher) distributed amongst the players in the
field, classified under four broad categories,
including Conservation Architects, Architects ('Perit'
the local Architect and Civil Engineer),
Administration staff and Contractors, it was possible
to take a snap shot of the local industry and its current
understanding of restoration. The aim was to arrive at
a set of conclusions identifying restoration principles
guiding (local) interventions with particular
reference to the replacement and/or the plastic repair
of the stone - the main types of intervention
methodologies usually adopted on local building
typology.
“Prima di essere una tecnica, il restuaro deve essere
una filosofia” (Carbonara 1997: p. 388) Restoration
must be a philosophy before being a technique).
Hence, the 'local' classification of the 'aims of
restoration', from the research, is as follows:
1. Improvement of the legibility of form and content
2. Retention of all original material
3. Interpretation/presentation
4. Aesthetic unity
5. Preservation in 'present' state
6. Expression of spiritual value of the building
7. Expression of artist's intent
8. Stylistic unity
9. Regaining 'original splendour'
10. Depiction of a particular period of time in history
11. Returning a place to a known earlier state
12. Returning a place to original form/configuration
Hence, it is implied that the main considerations
motivating the decision to intervene locally, are
classified as follows:
1. Structural - concern about safety, collapse or
serious failure
2. Authenticity - minimum 'necessary' intervention
3. Aesthetic architectural completeness vs. revealing
the marks of time
4. Functional understanding the artist's intent for
each individual stone element
5. Resources expertise, time, budget
6. Client's vision
Main Issues
The major concern is nonetheless arriving at the
decision to actually intervene and to what extent.
This short paper introduces some philosophical
aspects of the study, mainly confronting 'historic' and
the 'aesthetic' cases for restoration, in the light of the
local classification of the 'aims of restoration' and the
'main considerations' motivating the decision to
intervene. Furthermore, the issue of arriving at
deciding between replacement and plastic repair, and
the advantages of each method over the other, are also
highlighted.
The structural motivation is an undisputed factor.
Nonetheless, when looking at both the above
classifications, the aim of 'minimum intervention'
immediately followed by the 'aesthetic' motivations,
highlight the struggle to achieve the balance between
Brandi's 'istanze' - the 'historic' and the 'aesthetic'
(Brandi, 2000).
An approach focusing exclusively on the retention of
the fabric itself is somewhat arrogant towards all
future generations, we deciding to be the last
generation to see the historic buildings in the form in
which they were designed, leaving them with barely
recognisable features (Hill, 1995). A difference has to
be made between a ruin and an objet d’art which still
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has 'potential unity' (Brandi, 2000). attitudes of 'no
intervention', whatever the circumstance, will result
in buildings left to 'ruin'.
Hence, the infallible commandment to 'Know your
building' (Earl, 2003) - understanding the building to
express the message, or messages, that the artist
'originally intended' to convey through the material
fabric (and surface finish) of his work (Chung, 2005),
reinstating 'potential unity' (Brandi, 2000). This
implies distinguishing between 'accumulations of
dirt' and 'intended weathering marks' (Mostafavi &
Leatherbarrow, 1993). Furthermore, the conservatorrestorer must understand the 'functional' role of the
particular stone in the context (function).
The conservation architect must “educate him/her
self to understand the art-historical and
archaeological importance and character of the
particular structure, and develop a sensitivity
towards the preoccupations of the different groups
and disciplines interested in its continued
preservation” (Ashurst & Dimes, 2001: p. 8), striving
to achieve a balance between the different values and
intent(s) (Price et al., 1996), i.e., “restraining the
process of decay without damaging the character of
building” (Earl, 2003: p.73). This has to be done by
respecting the 'historical evidence' of the fabric, so as
not to destroy the building's authenticity (Brandi,
2000), whilst understanding and reinstating the
'surface effects' intended by the artist. Hence, it is
none other than arriving at establishing the
'intervention's intent' (Price et al., 1996).
The intervention
When the decision is taken to intervene, the choice of
the methodology is influenced by a number of factors
including: the building materials, size of the loss, its
location (e.g. decorative element or plain ashlar),
type and causes of deterioration, the availability of
resources in terms of time, money, and expertise, and
also context (Griswold & Uricheck, 1998).
As a general rule, no defective masonry that can be
secured in situ should be taken down (CADW, 2003);
if anything, this is repaired (TPS, 2006). It should be
remembered that it is replacement, not retention of
original fabric that has to be justified! (Ashurst &
Dimes, 2001) Sometimes, it might also be wise to
'buy time' in the hope that some better technique will
be evolved, especially if present methodologies
might prejudice future works of conservation.
Nonetheless, what must be avoided is allowing stone
elements to decay beyond the point of recovering the
original form, with the design lost forever (Hill,
1995). This further stresses the importance of
16
9
accurately replicating the replaced stone element,
over a 'simplified' version which is sometimes
suggested in the name of 'authenticity'.
On the other hand, careful attention must be paid to
the specification of finishes on both face and joints so
that the 'character' of the old masonry is matched and
the new blends happily and unobtrusively with the
old even before weathering has commenced (Ashurst
& Dimes, 2001). The local classification of the
motivations influencing the decision to replace
stonework, over plastic repair, is:
1. Structural - ensure stability
2. Longer life span
3. Requires less specialised skill
4. Cheaper
5. Guaranteed performance
6. Preserves better the surrounding stone
7. Minimal possibility of introducing salts
An alternative to replacing stonework is the use of
plastic repairs, or 'Architectural dentistry' (CADW,
2003). The greatest danger is the tendency for every
blemish, however tiny, in wall to be 'repaired'!
(Ashurst & Dimes, 2001) Nonetheless, when
properly prepared and applied, plastic repair is not
cheap and is generally more expensive than stone
replacement due to the amount of labour involved.
Furthermore, locally, plastic repair is preferred as it
is:
1. 'Reversible'
2. Ensures the retention of more of the original fabric
3. Acts as a 'sacrificial' zone
4. It is less visually intrusive as it blends-in more with
the surrounding stonework
Furthermore, the intervention programme is to be
built on a sound philosophical basis, which must be
clearly understood by all those involved in the
project, from the conservation architect to the actual
operative on site. This will provide consistency of
intervention when addressing the individual stone
elements, as well as ensure that the final result is in
accordance with the 'intervention's intent'.
Bibliography
Ashurst, J., & Dimes, F. G. (2001), Conservation of building and
decorative stone, Butterworth Heinemann, UK.
Brandi, C. (2000) Theory of Restoration, G. Basile, ed. Istituto
Centrale per il Restauro, Italy.
Carbonara, G. (1997), Avvicinamneto al restauro teoria, storia,
monumenti, Liguori Editori, Italia.
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CADW ( 2003) Technical Conservation Note 1. The repair and
preservation of historic masonry. Wales, UK, 2003,
http://www.cadw.wales.gov.uk/upload/resourcepool/masonry
%20notes%20english7511.pdf viewed 20 May 2006.
Chung, S. (2005), 'East Asian Values in Historic Conservation',
Journal of Architectural Conservation, vol. 11, no. 1, pp. 55-70.
Earl, J. (2003), Building conservation philosophy, 3rd edn,
Donhead, UK.
Griswold, J. & Uricheck, S. (1998), 'Loss compensation
methods for stone', Journal of the American Institute for
C o n s e r v a t i o n , v o l . 2 7 ,
n o . 1 ,
http://aic.stanford.edu/jaic/articles viewed 7 June 2006.
Hill, P. (1995), 'Conservation and the Stonemason', Journal of
Architectural Conservation, vol. 1, no. 2, pp. 7-20.
17
9
Mostafavi, M. & Leatherbarrow, D. (1993), On weathering the
life of buildings in time, The Mitt Press, Cambridge.
Price, N.S., Talley Jr., M.K. & Melucco Vaccaro, A. eds (1996)
'Introduction to Part II. The Original Intent of the Artist' in:
Readings in Conservation Historical and Philosophic al Issues
in the Conservation of Cultural Heritage, The Getty
Conservation Institute, Los Angeles, 1996, pp. 165-166.
Technical Preservation Services (TPS) of the Natonal Park
Service, US (2006) The Secretary of the Interior's Standards for
Rehabilitation. Introduction to the Standards, Technical
p r e s e r v a t i o n S e r v i c e s , h t t p : / / w w w. c r. n p s . g o v /
hps/TPS/tax/rhb/stand.htm viewed 22 May 2006.
D.Zahra: david.zahra@aom.com.mt
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18
Recording wathering and decay:
Differential performance of
red sandstones with mason
marks with dates from 1270
to 1320 in the external
facades of the Freiburg
Cathedral (Germany).
S uperimposed, a modern
graffiti closes a long history
of “anthropic” decay.
Stains in marble produced by
the oxidation of inclusions in
a marble at the “Basilica
Julia” in the Roman Forum,
Rome, Italy.
(Picture: M. Gomez-Heras)
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19
The dissolution of limestone
in the lapiaz near the
Monastery of Lluc, Mallorca,
Spain.
(Picture: M. Gomez-Heras)
Differential weathering in sandstones due to the presence
of hardened iron-rich Liesegang rings. Yehliu, Taiwan.
(Picture: B. Smith)
10 cm
How will these forms evolve due to climate evolution?
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ONGOING PROJECTS:
Rapid, catastrophic decay of building limestones:
Implications for masonry selection and lifetime
behaviour.
Project Maternas. Durability of materials in
infrastructures and buildings; Conservation of
Heritage.
PROJECT
maternas
Heritage Conservation
maternas is a 4-year (January 2006 - December
2009) programme of activities between research
groups funded by the Regional Government of
Madrid ( 521,000 €) .
The Instituto de Geología Económica (a joint
institute belonging to the Spanish Research Council
and the Complutense University of Madrid, CSICUCM) is the coordinator of this programme, which
includes public research institutions (24 researchers
in 6 centres) in adition to other 14 associated centres,
enterprises and associations. The philosophy of this
project aims to complementarily carry out training
activities and popularization of science in addition to
the research.
The determination of the durability differences of the
materials between rural and urban environments, the
identification of new indicators of the state of decay
through non-destructive techniques and the research
of traditional conservation techniques and its
recovery, are among the main scientific-technologic
objectives of this project.
Project Coordinator:
Dr. Rafael Fort (rafort@geo.ucm.es)
Further information:
http://www.maternas.es
The initiative is being undertaken by a team
combining state-of-the-art expertise in
Geomorphology, Physics and Civil Engineering
from Queen's University Belfast, City University in
London and Oxford University. Funded by the
Engineering and Physical Sciences Research
Council (EPSRC), this 3-year (2006-2009) research
project is receiving total funding of just over
£546,000.
Limestone is the main construction material used in
many of the UK's most historic buildings, including
St Paul's, Lincoln and Wells Cathedrals and many
Oxbridge colleges. Although basic knowledge exists
about the general causes of limestone decay, it is not
known why decay takes place in unpredictable fits
and starts or why it accelerates in some parts of a
building but not in others.
Understanding what lies behind these processes is
vital not only to enable action to be taken before
decay spirals out of control, but also to ensure that
conservation decisions do not lead to premature and
unnecessary replacement of limestone blocks and
avoidable expense.
In the new project, optical sensors will be developed
that can monitor how limestone blocks are affected
by traffic pollution, road salt, temperature, humidity
and wetness, detecting subtle changes in the blocks
due to changing moisture levels and salt movement,
for instance. The sensors will be installed in a
boundary wall at Worcester College, Oxford, and
other limestone structures. Information will be fed
from the sensors, via fibre-optic cable, to a data
logger and analysed to assess how decay correlates
with the limestone's precise physical, chemical and
mineralogical characteristics and with different
environmental factors.
Senior Project Partner:
Prof. B.J. Smith (b.smith@qub.ac.uk)
Further information:
http://www.limestonedecay.com
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NEWLY FUNDED PROJECTS:
The application of geostatistical analysis to the
prediction and modelling of the decay dynamics of
masonry materials.
Accurate prediction of the behaviour of masonry
materials is crucial for building stone conservation
and future stone cladding building strategies. A long
established body of research has provided increased
understanding of the factors that trigger stone decay
and an awareness of the unpredictability of decay
dynamics. It is precisely this unpredictability of
stone decay processes that can present significant
problems when planning conservation and future
stone building strategies. Previous research by the
Weathering Research Group (WRG) at Queen's
University Belfast has centered on surface
modification of building stones and feedback
mechanisms in the decay of sandstones. This has
provided a conceptual model of building stone decay.
This research aims to quantitatively test the
conceptual model through geostatistical analysis.
Recorded data from weathering trials will be used to
quantify relationships between variables at a series of
stages through weathering simulations to monitor the
underlying processes and ultimately predict and
model the dynamics of stone decay. The aims of the
research are:
21
This project is innovative for several reasons. These
comprise the detailed 3D measurement and sampling
scheme employed to monitor stone decay and the
application of 2D spatial analysis and 3D
geostatistical simulation to model the dynamics of
stone decay. The project also has the potential with
regard to the assessment of other masonry materials
such as concrete and reconstituted stone.
Project Coordinator:
Dr. Jennifer McKinley
School of Geography, Archaeology and
Palaeoecology (GAP),
Queen's University Belfast,
Belfast BT7 1NN.
N.Ireland
j.mckinley@qub.ac.uk
· To compliment and extend the understanding of
decay dynamics of masonry materials and complex
sandstone weathering decay.
· To provide a quantitative basis and predictive
potency for the conceptual model of rapid sandstone
decay.
This will be achieved through two specific strands of
investigation:
· Examination and quantification of rates and patterns
of stone decay through salt weathering cycles.
· Identification and analysis of decay processes and
pathways and investigation of positive feedback
mechanisms through geostatistical techniques
comprising spatial prediction, simulation and
modelling.
Three dimensional representation of permeability
characteristics sandstone blocks (adapted from McKinley et al.,
2006. Geostatistical analysis in weathering studies: case study
of Stanton Moor building sandstone. Earth Surface Processes
and Landforms, 31, 950-969.)
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22
NEWS
Proposals for ESF Research Networking
Programmes
Funding oportunities:
ESF EUROCORES (European Collaborative
Research)
The EUROCORES Scheme offers a flexible
framework for researchers from Europe to address
questions which are best addressed in larger scale
collaborative research programmes. It allows
working “at the bench” in collaborative research
projects by excellent researchers from different
countries and when appropriate including colleagues
from, for example, the US.
Proposals for themes: Following the EUROCORES
theme call around five new themes for collaborative
research in and across all scientific fields will be
selected through international peer review.
Deadline for submitting proposals: 1st June 2007
Further information:
http://www.esf.org/eurocores
Proposals for ESF Research Conferences 2009
The ESF Research Conferences Scheme is a highlevel conference programme in partnership with
national and international organisations, including
universities. The Scheme provides the opportunity
for leading scientists and young researchers to meet
in an informal setting for discussions at the highest
level on the most recent developments in their field of
research. It also acts as a catalyst for creating new
synergistic contacts throughout Europe and with the
rest of the world.
Conferences are interdisciplinary when appropriate
and last between four and five days. Up to 150 invited
speakers and participants may attend.
Deadline for submission of proposals: 1st October
2007
Further information:
http://www.esf.org/conferences
These long-term research networking programmes
are the platform for nationally funded research
groups to address major scientific and research
infrastructure issues with the goal to advance the
frontiers of science.
Deadline for submitting proposals: 1st October
2007
Further information:
Http://www.esf.org/programmes
Job oportunities:
Post-Doctoral Research Assistant
Climate change, moisture regimes and decay of
stone monoliths in southern England.
A three-year PDRA position is available from 1
October 2007 to work on a joint project between the
Oxford University Centre for the Environment
(OUCE) and the Institute for Materials and
Processes, University of Edinburgh. The project is
funded by a grant from the Leverhulme Trust and
directed by Dr Heather Viles.
The project is to investigate the decay of stone
structures in southern England, and to assess the
impact of climate change on damage processes. The
study combines field observations with laboratory
and mathematical modelling. The project is to be run
in collaboration with Professor Chris Hall,
University of Edinburgh who will supervise a
postgraduate studentship which will also be funded
by the project.
The PDRA will be responsible for the field and
laboratory experiment component of the project.
He/she will work closely with the postgraduate
student in Edinburgh (who will be responsible for
carrying out modelling of water transport through
stone) and Professor Hall and Dr Viles. A strong
interest and demonstrated aptitude for field
monitoring and laboratory experimentation is
required. The candidate should possess a PhD in a
relevant subject area. A clean driving licence would
be an advantage as the project will involve some
travel within the South of England.
Further information:
http://www.ouce.ox.ac.uk/news/jobs/070510.php
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23
Forthcoming events:
International Geological Congress
LACONA VII
Since 1878, the International
Geological Congress - IGC
has every four years been the
meeting place for people
interested in Earth Science.
In 2008 the Nordic countries
will arrange the 33rd
International Geological
Congress in Oslo (6-14
August, 2008).
The Spanish National
Research Council (CSIC) in
collaboration with the CSIC
Thematic Network on
Cultural Heritage are pleased
to announce the upcoming
International Conference on
Lasers in the Conservation of
Artworks, "LACONA VII",
which will be held at the
main auditorium of CSIC in
Madrid on September 17-21,
2007.
LACONA VII continues the tradition of previous
LACONA conferences held in 1995 (Heraklion,
Greece), 1997 (Liverpool, UK), 1999 (Florence,
Italy), 2001 (Paris, France), 2003 (Osnabruek,
Germany) and 2005 (Vienna, Austria) with an
increased number of participants and contributions in
every event of the series.
The field of LACONA has gained enormously in
importance in the last decades with a number of
monuments of high historical and artistic value (e.g.
St. Stephens Cathedral in Vienna, Notre Dame of
Paris, Santa Maria dei Fiori, Florence, etc) been
cleaned or measured by laser. In the Spanish arena the
list of monuments that have been restored using
lasers include Cathedral of Seville, Burgos Museum,
several Mudejar style churches in Aragón (World
Heritage listed), Cathedral of Jaca, Cathedral of
Santiago de Compostela, etc. As a consequence of the
research carried out and the practical demonstration
of the advantages of laser tools, the use of lasers has
been increasingly implemented worldwide in the
activities related with artwork conservation and
management
This unique event will gather scientists, conservatorrestorers, companies, architects, decision-makers
and other experts involved in conservation projects or
in research of new laser equipment from around the
world. Furthermore, we are planning to have a vendor
session during the program.
Deadlines:
30 November 2007: Geohost application
1 February 2008: Abstract submission and field trip
registration
31 March 2008: Registration fee deadline for
inclusion of accepted abstract in programme.
15 April 2008: End of early registration and payment
Further information:
http://www.33igc.org/
International Congress on Deterioration and
Conservation of Stone
Nicolaus Copernicus University organizes the 11th
International Congress on Deterioration and
Conservation of Stone to be held in Torun from the
15th to the 20th September 2008.
Further information:
http://www.lacona7.es
Further information:
http://www.stone2008.pl