Practical use of multispectral satellite images in ...

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7. RS and GIS for Cultural Heritage Management and Documentation 8. REFERENCE

Bhattacharya, Asis. 2007. Remote Sensing for Archaeology. Proc Vol on seminar 'Remote Sensing Archaeology', Kolkata Sabins Jr, Floyd F. 1978. Remote Sensing Principles and Interpretation. Freeman and Co

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9. ACKNOWLEDGEMENT

I thank Dr. K Vinod Kumar of NRSA, India who worked with me in this project.

O.GRØN, F.A.STYLEGAR. S.PAL~ et al. - Use of satellite images in Norwegian Cultural Heritage Management

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Practical use of multispectral satellite images in general Norwegian Cultural Heritage Management and focused Viking Age research. Experiences from South-Western Norway. O.Grøn', F.A.Stylega?, S.Palmft3, S.Aase4. P.Orlandos, K.Esbensen6, S. Kucheryavski7 1 Langlands Museum, Rudkøbing, 5900, Denmark, [email protected] 2 Vest Agder Fylkeskommune, Tordenskjoldsgate 65, 4614 Kristiansand, Norway, fransarne.stylegar@valno 3 Langelands Museum, Rudkøbing, 5900 Denmark, [email protected] 4 Bifrost & Draupne as, Haraldsgata 110, Postboks 420, 5501 Haugesund, Norway, [email protected] 5 University of Palermo, Dipartimento di Rappresentazione, Via delle Scienze (Parco d'Orleans), 90128 Palermo, halg, [email protected] 6 Aalborg University, ACABS Research Group (Applied Chemometrics, Analytical Chemistry, Sampling). Niels Bohrsvej 8, 6700 Esbjerg, Denmark, [email protected] 7 Aalborg University, ACABS Research Group (Applied Chernometrics, Analytical Chemistry, Sampling). Niels Bohrsvej 8, 6700 Esbjerg, Denmark, [email protected] Keywords: Remote Sensing, Archaeology, Norway, Cultural Heritage

Figures 1-2. ( I, left) Palaeochannel (P) in South 24 Parganas of West Bengai, India are the good archaeological sites. (2, right) Kondapur, Andhra Pradesh, India.

ABSTRACT The use of high-resolution multispectral satellite images has through 2007 been applied to practical Cultural Heritage management as well as a focussed Viking Age research project in 5 study areas in South-Western Norway with 1386 registered archaeological sites. The project has so far revealed an additional 1509 anomalies interpreted as the chemical signatures of archaeological mounds, houses, roads, inhumation graves, cooking pits etc. A beginning groundverification carried out by the county-based Cultural Heritage management system and the project itself indicates a high fraction of hits in this population of anomalies. The presentation will discuss possible methodological improvements. 1 INTRODUCTION This paper connects two related themes: the development of multi- and hyperspectral, hence forth refeffed to as `spectral' archaeological survey methodology as well as its practical application to the management of cultural heritage from the Viking Age and the younger Iron Age. Spectral recordings appear, according to our present experience, to facilitate a non-destructive and cost effective way of locating cultural heritage. From an archaeological point of view more efficient methods for mapping and monitoring of cultural heritage is needed. Traditional field survey unaccompanied with other methods only reveals a fraction of sites that must be taken into consideration in modem cultural heritage management. The spectral survey techniques seem to facilitate an approach where qualified prognosis about the location of archaeological sites can be incorporated into the planning phase of larger projects, thus minimising the conflict between construction and cultural heritage interests and increasing time efficiency and reducing costs involved in cultural heritage management (Grøn et al., 2004b; 2005). The SW Norwegian satellite project commenced in the beginning of 2007 and is a collaboration between Vest Agder County, Norway, Trygge Barnhager as, Norway, Langelands Museum, Denmark, University of Palermo, Italy, and Ålborg University, Denmark. The project operates in 5 study areas in SW Norway in Vest Agder and Rogaland counties, in a number of the areas with a close collaboration with the local cultural heritage authorities, in order for the remote sensing data to be directly applied to cultural heritage management strategies and verified through targeted archaeological land survey. Additionally geo-chemical verification is to be carried out in 2008. The 1386 of registered archaeological sites in the study areas have through the project period been increased with an additional 1509 possible sites. In the following set of examples different aspects of our work will be presented. 2 METHODOLOGY Spectral survey techniques are not only of importance for archaeological cultural heritage management. It also strengthens archaeological research potential, providing information about the old road systems that connected settlements and cemeteries thus facilitating a better understanding of the relation between the archaeological and historical sites in the landscape. Parallel with the experimental use of spectral survey techniques based on visual inspection, experiments with different types of semi-automatised pattem recognition have been carried out. Algorithm-based approaches seem unable to provide a reliable distinction between non-archaeological anomalies and archaeological sites apart from those that are highly visible due to the strong and uniform spatial configurations such as mounds

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13.GRØN, F.A.STYLEGAR. S.PAL~ et al. - Use of satellite images in Norwegian Cultural Heritage Management

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surrounded by circular ditches (Grøn et al:, 2005). Significantly better results have been obtained in preliminary experiments with multivariate techniques. However it will take years before such a methodology can be applied to practical cultural management, because of the problems with geological background noise as well as other factors. ft is obvious that the application of a fully automatised pattem recognition not involving a trained observer for quality control will not becorne a reality in the currently visual future. 3 EXAMPLES 3.1 Iran Age cooking pits In 2007 large clusters of geometrically irregular dark patches measuring 1-3 meters interpreted as cooking pits where observed within 4 of the 5 study areas. In Norway such cooking pits normally date to the Iron Age. The same year one of the newly observed clusters in Spangereid caused the archaeological authorities to demand a trial excavation due to the planved expansion of a plant nursery. Approximately thirty cooking pits where uncovered from the trenches. One was C14 dated to 1590 +/-50 BP (Beta-241096). The identification and subsequent verification of the cooking pits in Spangereid has demonstrated that not only large archaeological features can be identified but also small scale archaeological features can readily be distinguished through visual inspection. Furthermore it has also proved the value of utilising satellite images as an integrated element in cultural heritage management.

Figure 3 Lefl - Feature at Engeløy interpreted as a Viking Age nobility house with bending sides. Right - Feature interpreted as a military camp through excavation which is located 620 m NE of the nobility house. The raised peat watts are visible (QuickBird-copyright: Digital Globe). Zn P

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Figure I Lefl QuickBird panchromatic satellite image of cooking pits from Mitdbø, Spangereid. Right QuickBird panchromatic satellite image of possible cooking pits Eide, Karmøy. (QuickBird-copyright: Digital Globe): 3.2 The Huseby Chapel The Norwegian cultural heritage database contains numerous 'løst' historical cultural heritage sites with their approximate positions as they are given in historical sources. One case is the royal chapel in Huseby. The chapel is one of fourteen stone built royal chapels constructed in Norway during the Medieval Period. One of the papal letters from 1308 refers to the chapel as `Ecclesia Sancti Laurentis de Lista,' (Stylegar, 1992) the foundations still being visible in the 19th century, (fig. 2 — sketch) The use of the QuickBird satellite imagery made it possible to pinpoint the chapel's exact location as a feature that did not fit inlo the pattem of old field boundaries. An anomaly measuring approximately 7 * 14 meters was observed in the panchromatic satellite image with a possible cupols measuring 5 meters in width and 3 meters in depth. Sounding with a probe proved subsequently that the observed feature conjoined with a stone foundation.

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Figure 4 The feature interpreted as a Viking Age nobility house in relation to the concentration in the plough soil of — phosphates (P) and — Right — zinc (Zn). 3.3 The Engeløy house Engeløy near Lofoten a feature interpreted as a Viking Age nobility house was observed 620 m SW of a socalled `courtyard sile' construed as a military camp and dated to the Viking Age (Grøn et al., 2004a; Storli, 2001). Information from the present owner has established that earlier the site was covered by peat which was removed manually earlier this century. Relatively late formation of peat covering Viking Age features is not unusual in Norway. A geo-chemical analysis of the house with samples taken in a 2 m firid for phosphates (P), zinc (Zn), iron (Fe), copper (Cu) and manganese (Mn) displayed in the plough soil features with some correspondence with the observed anomaly interpreted as two overlapping nobility houses (fig. 4). The other samples taken from the plough soil and from the sub layer display straight, linear features parallel to the house, which may reflect the distribution of the metals in the shallow sand/gravel ridge the house was located on which appears to belong to an old beach system. Altematively is can reflect mechanical agricultural dispersal of these metals to the poor soil. Analyses of backup samples indicate that the values measured are genuine. Permission for a test excavation on the site has been applied for to the local cultural heritage authorities. 4 FROM MULTISPECTRAL TO HYPERSPECTRAL-DISCUSSION AND CONCLUSION

Figure 2 Right - QuickBird panchromatic satellite image of royal chapel in Huseby, Lista. 14 sketch of the foundations from 1920s when they were dug free. Afierwards the information about the position was last. Broken lines represent old field boundaries (QuickBird-copyright: Digital Globe).

Mounds due to their high visibility in the landscape are the predominant type of sites registered within the Norwegian national database of cultural heritage sites Askeladden'. This dominance, however, is not representative for the total population of archaeological sites that exist in the landscape. The project has in

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the five study areas identified hundreds of hitherto un-registered `invisible' mounds (ligure 5). In addition, however, it has revealed large numbers of houses, roads and small scale features such as post holes, cooking pits and small oblong features interpreted as inhumation graves. Sites have also been located due to approximate locations given in historical sources. Many of these historical sites are registered within the Norwegian cultural heritage database with imprecise locations covering several fields. With the spectral survey techniques such sites can be situated quicker and more cost effectively than by traditional field survey techniques.

E. S. MALINVERNI. G. FANGI -

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Comparative cluster analysis to localize emergencies in archaeology E. S. Malinverni, G. Fangi DARDUS, Engineering Faculty, Universitå Politecnica delle Marche. Ancona, 60131, halg, e.s.malinverni/[email protected]

Keywords: Remote Sensing, Quickbird, K-means, Fuzzy classification, Open source, Archaeology

Figure 5 Left aerial photograph from Karmøg depicting same area as possible mounds seen in QuickBird image right. (www.fonnnakart.no: 1/6/08 & QuickBird-copyright.• Digital Globe).

The development of recording techniques with better spectral resolution (hundreds of bands instead of the four bands available in today's high-resolution multispectral recordings) in addition to better spatial resolution appears to facilitate a promising technological platform for the development of better cultural heritage monitoring and management systems as well as archaeological research. The increasing commercial demand for smoother geo-correction methods and improved ways of handling the enormous amounts of data collected supports such a development. The first experiences with hyperspectral images recorded with an airborne HySpex scanner support such an optimism (Grøn et al., 2006).

ABSTRACT: In the Northwestern Peru, near the city of Trujillo, an Italian Archaeological Mission (MIPE), in tight collaboration with the INC, National Institute of Culture of Peru, works on the site of Chan-Chan, the widest archaeological complex of the world for the constructions in raw earth. The mission carried out a multidisciplinary survey with the intentions to study a methodology for the site maintenance and the creation of a local center of documentation. Inside this project we want to illustrate a step of the research based on the analysis of a QUICKBIRD high resolution image. By means of some image classification techniques it has been possible to investigate the whole archaeological site, with the aim of a better definition of its general features and of a contribution to the exploitation of the surroundings. This analysis was carried out in open source environment performing two different algorithms and comparing the results. Not having an available set of reliable ground truth of the study area it has been inevitable to follow an unsupervised approach. The off-line clustering techniques applied have been: K-means clustering and Fuzzy K-means clustering. Both techniques rely on minimizing a cost function of dissimilarity (distance) measure, but in the fuzzy approach each data points belongs to a cluster with a fuzzy membership degree, overcoming the problem of data group overlapping. The resulted classification clearly separates the central archaeological site from the areas intensively cultivated and besides puts in evidence the coastal band, characterized by a reduced parceling and by the presence of damp zones. Another purpose of the present research has been also to individualize the principal components of the particular territorial system of Chan Chan and, possibly, to put in evidence some archaeological emergencies discovering new marks, signs. We performed every phase by the software ILWIS 3.4 (Integrated Land and Water Information System) developed by the ITC of Enschede and Open Source from July 2007.

REFERENCE

1 INTRODUCTION

Grøn, 0., Aurdal, L., Christensen, F., Loska, A. 2004a. Mapping and verifying invisible archaeological sites in agricultural fields by means of multi-spectral satellite images and soil chemistry. Proc.of Intern. Conference on Remote Sensing Archaeology Oct. 18-21, 2004, Beijing, China. 83-90. Grøn, 0., Aurdal, L., Christensen, E, Tømmervik, H., Loska, A. 2004b. Locating invisible cultural heritage sites in agricultural fields. Evaluation of inethods for satellite monitoring of cultural heritage sites — results 2003. The Norwegian Directorate for Cultural Heritage. Oslo. Grøn, 0., Aurdal, L., Christensen, F., Solberg, R., MacPhail, R., Lous, J., Loska, A., 2005. Locating invisible cultural heritage sites in agricultural fields. Development of methods for satellite monitoring of cultural heritage sires report 2004. Research report from the Norwegian Directorate for Cultural Heritage. Oslo. Grøn, 0., Christensen. F.. Orlando, P., Baarstad, I., MacPhail, R. 2006. Hyperspectral and multispectral perspectives on the prehistoric cultural landscape; the ground-truthed chemical character of prehistoric settlement and infrastructure as identified from space. From Space to Place: 2nd International Conference an Remote Sensing in Archaeology. (eds.) S. Campana and M. Forte. Proceedings of the 2nd International Workshop, Rome, Italy, December 4-7, 2006, 143-147 Storli, I. 2001. Tunanleggenes rolle i nordnorsk jernalder. VIKING 2001. 87-111 Stylegar, F.-A. 1996: Sancti Laurentis de Lista — et kongelig kapel! på Huseby. Årsskrift Agder historielag nr. 72, 1996, pp. 30-36.

In the Northwestern Peru, near the city of Trujillo the archaeological complex of the city of Chan Chan, capital of the Kingdom Chimii, covers an area of about 14 ktn 2. This site, of exceptional historical-cultural value, because it is the widest archaeological complex of the world for the constructions in raw earth, is in the list of the monuments at rink of the UNESCO World Heritage. In fact it is in continuous deterioration, due to the atmospheric agents, to the uncontrolled agricultural activities, to the expansion of the area of Truijllo city and finally to the disfigurements of the so-called "tomberos". Since 2000 an Italian Archaeological Mission (MIPE), in tight collaboration with Italian CNR, Universitå Politecnica delle Marche (DARDUS) and the Institute National de Culture Peruvian (Inc), has carried out a multidisciplinary survey with the intentions to study a methodology for the maintenance of the site and the creation of a local center of documentation that can autonomously continue the activities of research and the formation of local technicians (Fangi et al., 2005). In the past we pointed out a step of research based on the remote sensing high resolution image classification performed by Envi software (Galli et al., 2005). Now in this occasion we present different unsupervised classification techniques implemented in an Open Source environment (ILWIS 3.4 ) underlying the potentiality of these solutions. We worked on a subset of the original QuickBird multi-resolution image acquired on 1005-2003 as Standard level with a ground resolution of 2,51 m and fumished by EurimageTm (corrections of the system, radiometric corrections, geometric corrections, organization in a specific cartographic system of reference: Datum WGS84, UTM projection, 17 Fuse, South Hemisphere are given) (kure 1).

Proceedings of the lst International EARSeL Workshop CNR, Rome, September 30 — October 4, 2008

Advances on Remote Sensing for Archaeology and Cultural Heritage Management Edited by

Rosa Lasaponara Nicola Masini CD-Rom included

• •.Y ARACNE

VII

Table af cantents Preface Rosa Lasaponara, Nicola Masini

Published for : EARSeL - European Association of Remote Sensing Laboratories CNR IMAA (Istituto di Metodologie di Analisi Ambientale) CNR - IBAM (Istituto per i Beni Archeologici e Monumentali)

Presentation Francesco D'Andria Vincenzo Cuomo

Acknowledgements

1. Satellite imagery for archaeology: data processing methods and study cases 1.1

Following O.G.S. Crawford: satellite images and field archaeology in Sudan M. Drzewiecki, W. Raczkowski

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The applicability of image processing techniques for archaeological exploration using space imagery: Talakadu - a case study M.B. Rajani, S.K. Patra

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Satellite-based archaeological research in the ancient territory of Hierapolis (Turkey) R. Lasaponara, N. Masini, G. Scardozzi

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Detection of burial mounds in high-resolution satellite images of agricultural land Ø. Due Trier, A. Loska, S. Øyen Larsen, R. Solberg

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A view on Greater Angkor: a multi-scatar approach for investigating the Khmer forests A. Traviglia

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Satellite remote sensing geoarchaeology of the ancient silver mine ofJabali, Yemen J.-P. Deroin, F. Tc;revgeol, I. N.AI-Ganad,P. Benoit, J. Heckes

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Published and distributed by Aracne Editrice s.r.l. via Raffaele Garofalo, 133 A-B, 00173 Rome, Italy. T. +39 (0)693781065, www.catalogoaracneeditrice.eu

Data fusion techniques for supporting and improving satellite-based archaeological research B. Aiazzi, S. Baronti, L. Alparone, R. Lasaponara, N. Masini

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Vicus Costanziaci between land and sea: Remote Sensing applications for the detection of the lost islands in the Venetian Lagoon A. Traviglia, D. Cottica, L. Fozzati

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Copyright Ci MMVIII ARACNE editrice S.r.l_

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Stereoscopic view, extracting DEM and cartography for archaeological purposes from Ikonos stereo pair: a case from Hierapolis of Phrygia territory (Turkey) G. Di Giacomo, I. Ditaranto, G. Scardozzi

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Cover design: Nicola Afflitto (IMAA-CNR)

Disclaimer: the Editors and the Publisher Aracne Editrice S.r.l. accept no responsibility for errors or omissions in the papers and shall not be liable for any damage to property or persons arising from the use of information contained herein.

ISBN

978-88-548-2030-2

No part of this book may be reproduced in any form, by print, photopnnt, microfilrn. microfiche. or any other means, without written permission from the publisher.

2. Aerial archaeology: from the historical photographs to multispectral and hyperspectral imagery 2.1

The future of aerial archaeology (or are algorithms the answer?) W.S. Hanson

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Aerial Archaeology in Italy. Recent research and future developments G. Ceraudo

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Giacomo Boni: a pioneer of the archaeological aerial photography L. Castrianni

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2.4

Images of Conflict: an archival research of Great War air photos and overview of the main applications B. Stichelbaut, J. Bourgeois

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2.5

Aerial survey and ancient landscapes in Salento (southern Apulia). Combining advanced

1' edition: September 2008

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