1

REMOTE SENSING IN

ARCHAEOLOGY

Presented by,

M.Anurupa

2

Contents• Introduction• Literature review• Case studies• Summary• Reference

3

INTRODUCTION Archaeology• The study of human history and

prehistory through the excavation of sites and the analysis of artifacts and other physical remains.

• These can range from small artifacts, such as arrowheads, to large buildings, such as pyramids.

• Often, these objects are buried and have to be carefully uncovered or excavated before they can be studied.

4

• Archaeologists must take notes, take photographs, and make maps so that can recreate how objects are associated or in relation to one another

• The visual mappings relating to the archaeological area will provide easy-comprehensible additional information to the decision makes, so it will ensure to keep on the archaeological studies in a systematic manner

• Traditional survey tools used in finding and recording sites are taken from land survey

• Archaeological surveyors use compasses, tape measures, stadium rods, and various other survey tools. Today, most archaeologists also employ electronic devices, such as Total Stations and Global Positioning System (GPS) units, to map an area or site.

5

Conventional vs Remote sensing

Conventional method

• Using conventional method small area can be mapped

• Cannot be used in all weather conditions

• Permissions are required in order to dig that particular site

• Artifacts can be destroyed • Destructive method

Remote sensing method

• Large area can be mapped• Can be used in all weather

conditions• No permissions are required

• Cannot be destroyed

• Non-destructive method

6

Remote sensing in Archaeology

• Remote Sensing refers to a wide variety of high-tech methods for collecting data pertaining to the physical or chemical properties of an archaeological site.

• Generally, these methods are split into two categories.

1. Aerial collection of data. • Data is collected from sensors installed on airplanes, helicopters, or

satellites. • As the sensors are flown over the ground surface they record the

way in which electromagnetic radiation interacts with targets on the ground.

• In the case of archaeology, the target of interest is the archaeological site

7

2. All near-ground surface technologies.

There are a wide variety of these techniques that are used in archaeology. These techniques are employed through the use of hand-held instruments that measure the magnetic or electrical properties of the soil at an archaeological site.

• Remote Sensing techniques have proven to be very useful for archaeologists by providing a means for collecting unique information that can inform the archaeologist on the locations and types of archaeological features present at a site.

8

Satellites and Sensors used:

• IRS-P6, also known as ResourceSat-1, is an Earth observation mission within the IRS (Indian Remote-Sensing Satellite) series of ISRO (Indian Space Research Organization). IRS-P6 is the continuation of the IRS-1C/1D missions with considerably enhanced capabilities.

Name Sensors Type Spectral range(µm)

Resolution (m)

Swath(km)

Revisit(days)

IRS P6 AWifs

LISS III LISS IV

MS

MS

MS

0.52-1.7µm

0.52-1.7 µm

0.52-0.86µm

56

23.5

5.8

740

141

23MS

5

24

5

9

Airborne Thematic Mapper (ATM)

• The eleven spectral channels of these instruments cover the visible(1-6) and near-infrared , shortwave infrared and thermal infrared

ATM Band Spectral range (µm)

1 0.42-0.45

2 0.45-0.52

3 0.52-0.60

4 0.605-0.625

5 0.63-0.69

6 0.695-0.75

10

Literature review

• Sandy Winterbottom & Tom Dawson (2003) used Airborne Remote Sensing to

detect buried archaeology. From NDVI images and Principal Component Analysis

they got fruitful results.

• Rejas. J et.al (2005) used remote sensing data for cultural heritage and human

habitats protection. Satellite images (Landsat ETM+, ASTER, ALI and Hyperion)

have been used to make a preliminary sites cartography, to extract current land

cover/use and to test models for detecting and/or confirming possible buried

archaeological structures.

• Farjas, M et.al (2008) have used Landsat ETM+, ASTER, ALI and Hyperion to

make a preliminary sites cartography, to extract land cover/use and to test models

for detecting and/or confirming possible buried archaeological structures

11

• Sarah Parcak(2009) presented avarieties of techniques for the detection of

archaeological features in Egypt, in order to understand greater anthropological

issues, including population densities, ancient settlement locations, and modeling

past human-environment interactions. Used Quickbird high resolution satellite

imagery in the detection of subsurface architectural features, and advanced

interpolation techniques.

• M.B.Rajani and S.Settar et.al (2010) studied that the sub-surface composition of

ruined ancient sites over time effect surface cover and traces of this phenomenon

can be identified on remote sensing images. Used Multispectral remote sensing

data to detect moats of archaeological sites.

12

Case study 1 (M.B.Rajani and S.Settar ,2010)

• Objective of the study: Detection of enclosure walls of ancient settlements in South India using multispectral remote sensing imagery.

• Study area : Three archaeological sites Beluru, Halebidu and Somanathapura in Karnataka, South India

• Satellite : IRS P6 LISS 4

13

• Mainly focused on detection of enclosure walls• Olden days-Defensive walls or fortification ,many times surrounded by

moats• Later got destroyed due to natural disasters, expansion of urban,

agricultural activities• Subsurface composition of ruined ancient site over time effects surface

cover. To identify those they used remote sensing images.• They have used Multispectral imagery in identifying dried and buried

moats and also fortifications• 3 sites in south india

1.Beluru

2.Halebidu

3.somanathapura

14

• Beluru: Temples within enclosure walls• RS image shows a circular signature of positive vegetation

marks Surrounding the temple• Indicating existence of moats surrounding enclosure walls• Buried structures affects the surface vegetation by causing

variations in their growth• Techniques like rationing, intensity hue saturation and

principal component analysis are used to enhance the image in order to improve the vegetation signatures

• Moats can be easily identified

15

16

• Halebidu: came to know multispectral imagery is better than PAN imagery• Once moats are detected using multi spectral imagery, PAN ( spectral

range0.5-0.85 microns, spatial resolution 2.5 m)image is used to know the boundaries

• With this exact shape of moats can be identified

17

• Somanathapura: Remotely sensed image taken from space reveals the temple and its alignments with the surrounding land cover features displaying a pattern that befits a bounding wall.

• Images shows an overall perspective of the landscape including the main temple, the river course, canal, roads and the subtle signature of the buried defensive wall.

• The features that are almost black are water bodies, with river Kaveri on the left and a lake on the right.

18

Case study 2 (Sandy Winterbottom & Tom Dawson , 2003)

• Objective of the study: Detecting buried Archaeology using Airborne Remote Sensing

• Study area : Islands of Coll and Tiree in Scotland

• Sensor: Airborne Thematic Mapper( ATM)

19

• The uncovering of archaeological sites as a result of coastal erosion is very common.

• Once revealed however, these important sites are then under serious threat from damage by further coastal erosion.

• A method is required which can be used to target unstable coastlines and determine the nature of the archaeological remains underneath.

• So the use of airborne multi-spectral remote sensing for detecting buried archaeological sites. The study was carried out on the islands of Coll and Tiree in Scotland.

• In the past those islands were visited by Beveridge and published a report

in which detailed information of archeological sites are given• Number of chapel sites and associated burial grounds

20

• These sites were subsequently revisited by the Ordnance Survey and by the Royal Commission on the Ancient and Historic Monuments of Scotland

• The visits revealed that many sites, particularly those in the dune fields, were no longer visible

21

• Techniques:

Visible, infra-red and thermal infra-red images were acquired by the NERC( Natural Environment Research Council  is a British research council) aircraft using the onboard Airborne Thematic Mapper(ATM) sensor .

• The images were processed and enhanced for visual interpretation

• Processing methods included creating false colour composites, NDVI images and Principal Component Analysis.

22

• Results of the case study: Daytime thermal images revealed small-scale topographic variations, which were useful for picking out abandoned enclosures and ruined buildings

• Thermal image revealing abandoned enclosures and ruined buildings.

23

• Subtle differences in agricultural soils were revealed from multi-spectral imagery, and in particular infra-red images.

• These differences in the images resulted from older cultivation patterns

• Infra-red image revealing older cultivation patterns.

24

• Daytime thermal images have revealed a possible chapel site

25

Summary:

• Satellite data in combination of cultural information and associated geometrical patterns can be used for detecting archaeological and historical sites.

• Various features such as buried walls, enclosures, abandoned farmsteads, buried structures (possibly chapels) and boundaries of structures can be detected.

• Infrared and NDVI images were good for detecting a wide range of features.

• Thermal images were good for picking up small scale topographic variations.

• Hence, remote sensing in archaeology is economical

26

References• Rajani.M.B andSettar.S (2010), Application of multispectral remote sensing

imagery in detection of enclosure walls of ancient settlements in South India, BAR International Series 2118, 3rd International Conference on Remote Sensing in Archaeology, Aug 17-19,2010.

• Sandy Winterbottom& Tom Dawson, (2003).Detecting buried Archaeology using Airborne Remote Sensing, e-journal, IEEE.

• Sarah Parcak(2009) .Pushing the envelope for satellite archaeology in Egypt: Quickbird feature detection, predictive site modeling, and thermal site signatures.3rd International Conference on Remote Sensing in Archaeology

• Farjas, M (2008). Archaeological remote sensing approach in Honduras. A project for cultural heritage and human habitats protection.3rd International Conference on Remote Sensing in Archaeology

• Rejas. J (2005). Used satellite data for cultural heritage and human habitats protection. 3rd International Conference on Remote Sensing in Archaeology

27

THANKYOU