Applications of satellite remote sensing for research and heritage management in Indian prehistory

Multidisciplinary spatial studies are relatively limited in Indian archaeology, despite their potential for research and heritage management. This paper discusses applications of satellite remote sensing, field studies and GIS, in the context of Palaeolithic archaeology. The study region covers an area of around 8000 km², in the state of Tamil Nadu, South India, and is characterized by a rich and diverse Palaeolithic record. Satellite images of varied spatial resolutions were interpreted to address both regional and site-specific research questions. Thematic maps were generated from satellite data and refined with intensive field investigations. These were used for demarcating sources of raw material, and in investigating variability in the distribution of sites through time in relation to a range of geological and geomorphological features. Satellite data and field studies also aided in mapping impacts on sites resulting from modern landuse patterns. The paper also discusses the development and testing of a model to detect potential areas where new sites may be rapidly located.     

Monitoring Islamic Archaeological Landscapes in Ethiopia Using Open Source Satellite Imagery

The African landscape is set to change dramatically in the coming years, and will have a detrimental impact on the inherent archaeological and cultural heritage elements if not monitored adequately. This paper explores how satellite imagery, in particular open source imagery (Google Earth, multispectral satellite imagery from Landsat and Sentinel-2), can be utilized to monitor and protect sites that are already known with particular reference to Islamic archaeological sites in Ethiopia. The four sites used are in different geographic and geomorphological areas: three on the Somali Plateau (Harlaa, Harar, and Sheikh Hussein), and one on the edge of the Afar Depression (Nora), and have varied histories. The results indicate that open source satellite imagery offers a mechanism for evaluating site status and conservation over time at a large scale, and can be used on data from other areas of Africa by heritage professionals in the African continent at no cost.     

Differential Doppler measurements of the ionosphere during a solar eclipse

The effects of the solar eclipse of 26 February 1979 on the ionosphere were measured using differential Doppler techniques. Nayy navigation satellite passes were monitored at 12 sites located across the North American continent. These data yield a measurement of the vertical columnar electron content along a north-south line. Different sites monitoring the same pass provide simultaneous observations of ionospheric variations along different longitude lines. Two satellite passes occurred during or just after the eclipse. These data show a shoulderjust northward of the umbra region and a trough just behind the umbra containing large horizontal gradients. This sharp trough recovered quickly with a half-life of about 10 min.     

Satellite Remote Sensing Methods for Monitoring Archaeological Tells in the Middle East

Abstract

Using a variety of types of satellite imagery (SPOT, Corona, Landsat, and Quickbird) and concentrating on archaeological sites in the Egyptian floodplain, this paper proposes methods for monitoring the rate of archaeological site destruction in the Middle East. This image analysis shows how tells can be documented and monitored from computers anywhere in the world, emphasizing the multispectral capabilities and applications of satellites. The effects of population growth, looting, urban expansion, and war on archaeological sites in Egypt are reviewed, and a system is proposed to record sites by focusing on their individual spectral profiles. The analysis demonstrates how satellite imagery analysis can be applied to similar flood plain environments in Israel, Jordan, Syria, Turkey, Iran, Afghanistan, and Iraq.     

Satellite Remote Sensing of Archaeological Vegetation Signatures in Coastal West Africa

This article discusses how archaeological sites in Sierra Leone, and by extension much of West Africa, can be identified through vegetation patterns (vegetation signatures) detectable in very high-resolution (VHR) multispectral satellite imagery. Settlement sites typically have a differing pattern of vegetation from the surrounding landscape, including concentrations of very large trees with sociocultural and historical significance: cotton (Ceiba pentandra) and baobab (Adansonia digitata). These features are conspicuous elements of the landscape both from the ground and in aerial imagery. Two complementary methods of using VHR multispectral satellite imagery are discussed in this paper: visual interpretation and semi-automated subpixel classification. These techniques are aiding ongoing archaeological survey of the Sierra Leone River Estuary. The impact of recently renewed industrial activity at a site of probable archaeological significance is also assessed through visually interpreted VHR satellite imagery.     

Editorial Introduction

Abstract

International response to the problem of looting of archaeological sites has been hampered by the difficulty of quantifying the damage done. The scarcity of reliable information negatively impacts professional and public policy making, rendering consensus about the scale of the problem and the effectiveness of policy responses difficult to achieve. We report here on the use of publicly-available satellite imagery for quantifying the damage caused by looting of archaeological sites in Jordan. The ease of use and affordability of imagery such as that provided by Google Earth make the identification, quantification, and monitoring of archaeological site looting possible at a level previously unimagined. Our findings about looting at archaeological sites in Jordan shed light on the potential for a broader application of the method.     

The application of quicklook NOAA AVHRR satellite imagery in Northern Scandinavia for synoptic weather analyses

The suitability of imagery from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA series of satellites for the synoptic classification of circulation trends in the European Arctic is assessed with reference to data from three climate stations. Simplified synoptic cyclonic classifications are derived from the satellite imagery and tested against climate data. Five classes of frontal system are derived from the tracking of systems over the UK‐Scandinavia‐Baltic region using 1460 satellite images over two years. An index based on the qualitative interpretation of satellite imagery was related to the reference data. The tracking of the systems in the imagery also facilitates a comparison of travel times across the region and the frequency of occurrence. Frontal systems that remain largely stationary over the Baltic were found to correlate best with precipitation at the reference sites. The paper thus investigates the use of AVHRR imagery for the categorisation of weather patterns towards deriving quantitative relationships between circulation classes and weather elements (such as temperature and precipitation) where, for example, climate data are sparse or where skills required for the interpretation of Height Potential Fields are lacking.     

Remote Sensing and Archaeological Prospection in Apulia,Italy

Abstract

When deployed in combination with ground control, archaeological surface survey, and environmental research, remote sensing based upon high-resolution multispectral satellite imagery allows large areas to be evaluated efficiently by a small team of researchers and contributes to a better understanding of an archaeological landscape. In 2007 and 2008, we analyzed ca. 100 sq km of imagery centered on L'Amastuola, Italy. Combining the evaluation of high-resolution multispectral imagery with concurrent ground control led to the discovery of 29 sites and significant off-site scatters during about four weeks of fieldwork. Our analysis indicates that most of the detected features reflect geological conditions amenable to past human habitation rather than subsurface archaeological remains. Earlier fieldwork by the Murge Tableland Survey (MTS) provided independent definitions for various types of sites and a large sample of sites and off-site scatters in the study area. Comparison of our remote-sensing guided efforts with the results of that survey suggests that our success rate is too high to be explained by random association and also illuminates the strengths and weaknesses of the respective methods, underscoring the need to integrate satellite image analysis with ground control and surface survey.     

Multitemporal analysis for preservation of obsidian sources from Melka Kunture (Ethiopia): integration of fieldwork activities,digital aerial photogrammetry and multispectral stereo-IKONOS II analysis

An integrated analysis of recent satellite imageries and dated aerial photos demonstrated to be a good investigation tool (Gallo et al., 2009) for the identification of new sites and for the assessment of landscape changes of wide archaeological areas in Ethiopia.     

Potential of satellite based sensors for studying distribution of archaeological sites along palaeo channels: Harappan sites a case study

A large number of remote sensing based studies have shown evidence of a prominent river system, which has become buried under sand cover of Thar Desert sometime during late Holocene. This major river has been identified as Sarasvati, a legendary river mentioned in ancient Indian texts. This region is rich with archaeological sites of Harappan civilization (2500–500 BC). The present study has utilised digital image processing and enhancements techniques on multisensor satellite data followed by field investigations to reconfirm known traces and detect hitherto unknown traces of palaeochannels of Sarasvati river through parts of Indus alluvial plain in Thar desert. Potentials of IRS-P4 OCM (Primarily an Ocean Color Sensor, with eight narrow spectral channels, high radiometric resolution of 12 bits and large swath of 1420 m) could be exploited for the first time to detect hitherto unknown traces of palaeochannels of Sarasvati river through sand dune topography of Thar desert in parts of Western Rajasthan in India and adjoining parts of Pakistan by applying Principal Component Analysis technique. Pattern of palaochannels indicate westward migration of the Sarasvati river in parts of Indus alluvial plain. Database of more than 1000 archaeological sites compiled from various published sources, prepared in GIS environment could be utilised to understand their relationship with identified courses of the Sarasvati palaeochannels. Through this study it was found that there is a large spread of Mature Harappan (2200–1700 BC) sites along the palaeochannel of the Sarasvati and its tributaries in north-west India, but late Harappan (1700–1500 BC) sites are limited to further west in adjoining regions of Pakistan indicating that the shift of cluster of settlements have followed the pattern of river migration towards west. Digital terrain modelling by superimposing archaeological sites on SRTM DEM along with draped satellite data (Resourcesat-1 AWiFS and IRS-1D LISS-III) has helped in identifying geomorphological guides for archaeological investigations such as presence of relict natural levees seen as raised mounds and coincidence of known archaeological sites over them. It is suggested that other relict natural levees or raised mounds adjoining the identified palaochannel courses may be taken up for further archaeological exploration.     

Observatory validation of Neolithic tells (“Magoules”) in the Thessalian plain,central Greece,using hyperspectral spectroradiometric data

This paper presents the results obtained from field spectroradiometric campaigns over Neolithic tells (“magoules”) located at the Thessalian region in Greece. In each one of the four archaeological sites selected, three sections were carried out using the GER 1500 handheld spectroradiometer. Spectral profiles of the sections and several vegetation indices such as Normalized Difference Vegetation Indices (NDVI) and Simple Ratio (SR) have been examined in this study. This is one of the first times that ground hyperspectral data are evaluated in such context of archaeological research for the spectral characterization of archaeological features. As it was found, ground spectroradiometric measurements can be efficiently used in order to support and validate satellite imagery results for the detection of archaeological sites.     

NDVI Variability in North East India

Abstract

The variability of the Normalized Difference Vegetation Index (NDVI) in north east India in response to rainfall and temperature was analysed using twice-monthly NOAA/AVHRR satellite imagery acquired during 1982–2002 from the GIMMS (Global Inventory Modeling and Mapping Studies) data-set. Corresponding rainfall and temperature estimates were extracted from the Climate Research Unit's CR TS 2.1 data-set for 34 study sites, chosen using the GLC 2000 land use categories. The selected sites represent nine land use categories under differing institutional frameworks. Results showed a weak linear relationship between the growing season rainfall and NDVI range when plotted in a scatter diagram. The negative correlation between NDVI and rainfall and temperature and NDVI in the study area was accentuated during the growing season and a one- and two-month lag for rainfall and temperature respectively was operating. A gain coefficient image to determine the temporal change in NDVI during the 21-year period indicated a consistent decline for much of the study area. Among the study sites those under state protection fared better than sites under other institutional frameworks. Along with rainfall and temperature, land use and institutional frameworks emerged as causative factors in the dynamics of vegetation greenness in north east India.     

Methods for assessing stormwater management at archaeological sites: Copan Ruins case study

Archaeological sites may be discovered by fortuitous soil erosion, but their protection requires deliberative stormwater management plans and estimates of runoff volumes. This paper uses the Maya site of Copan, Honduras to demonstrate widely applicable methods to estimate runoff, including use of satellite rainfall data processed by single parameter models. Our analysis compares present day estimates of runoff and erosion with those of two historic periods, 900 A.D during peak Maya occupation of the Great Plaza, and 1800 A.D. prior to excavation when the site was mostly forest covered. For each period, the watershed area, soil, land cover, and rainfall data were used with a single parameter Curve Number model to estimate the runoff volume for annual to decadal storms. The maximum runoff depth and erosive potential in conveyance channels was then computed with the HEC-RAS model. The models did not predict runoff would occur for the forested period of 1800 A.D., but predicted that runoff for 900 and post-1800 A.D was large enough to cause the erosion observed in the drainage channel today. Our results provide runoff magnitudes that demonstrate the need for Copan Maya designed stormwater removal infrastructure described in earlier archaeological analysis. The need for stormwater removal was also designed into the wet Maya site of Palenque, while stormwater capture and storage was designed into the Maya sites of Tikal, a drier site due to local drainage characteristics and water availability. Methods used in stormwater runoff analysis can empower communities and managers to develop scientifically and culturally appropriate non-structural management methods to conserve archaeological sites.     

On the Margins: Enduring Pre-Modern Water Management Strategies In and Around the Registan Desert,Afghanistan

The Registan Desert in southern Afghanistan has, like most deserts, traditionally been regarded as a barren, hostile space, devoid of human occupation other than occasional nomad campsites and an isolated 11th-century a.d. fortress. Detailed analysis of a strip of high resolution satellite imagery available through Google Earth and stretching into the Registan has revealed the presence of over 800 hitherto unrecorded archaeological sites. Many of these sites relate to water management, and predate the modern era. The water installations form networks of sites which facilitated the opportunistic exploitation of grazing following periodic rains, desert farming, travel, trade and exchange over hundreds of years, if not longer. Extrapolating from this detailed analysis, we argue that thousands of other sites have yet to be discovered in the Registan. These water management networks warrant further study in the field and protection from neglect, construction, recreational four-wheel driving, and looting.     

Optimum temporal and spectral window for monitoring crop marks over archaeological remains in the Mediterranean region

This paper aims to explore the formation of crops marks over archaeological features using remote sensing data. Crop marks are very important to archaeological research since they can reveal in an indirect way buried archaeological remains. Several researches have been able to locate subsurface relics via interpretation of multispectral and hyperspectral satellite images. However the best phenophase (time-window) where these crop marks are enhanced and which spectral bands are the most capable for this enhancement are still an open question for the scientific community. This study aims to address these fundamental aspects of Remote Sensing Archaeology. For this reason an extensive dataset was used: two control archaeological sites were constructed in two different areas of Cyprus (Alampra and Acheleia). In these areas both barley and wheat, were cultivated. In situ spectroradiometric measurements were taken over a whole phenological cycle (2001–2012) for both areas. More than 30 in situ campaigns were performed and more than 2600 ground measurements were collected. The phenological analysis of these measurements have shown that a period of only 15 days is best suitable for monitoring crop marks which is connected with one phenological stage; during the beginning of the boot stage of the crops. This period can be used in areas having similar climatic condition as Cyprus (Mediterranean region). Also as it was found, this phenological stage of crops might be also influenced by the climatic conditions of the area. The evaluation of a proposed Archaeological Index was performed at the Thessalian plain (central Greece), where several Neolithic settlements are established. The evaluation was made using both Hyperion and Landsat images. The results have shown that the proposed Archaeological Index is suitable for the enhancement of crop marks in satellite imagery.     

Critical Masses: Augmented Virtual Experiences and the Xenoplastic at Australia’s Cold War and Nuclear Heritage Sites

Critical Masses is a multidisciplinary pilot project that aims to graphically represent and mediate the histories, spaces and narratives concerning former nuclear installations within central Australia. These include the abandoned British atomic test sites at Emu Field and Maralinga, the Intercontinental Ballistic Missile (ICBM)/Intermediate Range Ballistic Missile (IRBM) rocket launchers at Woomera, and the decommissioned US National Security Agency early warning satellite base at Nurrungar. Significantly, each of these Cold War sites are situated in either hazardous, remote, secure and/or culturally sensitive areas and require sophisticated analysis and negotiation in order to best render their complexity for both online access and on-site tourism. In association with the Maralinga-Pilling Trust and traditional indigenous landowners a multi-tiered approach (re)creating these locations is being modelled across platforms for diverse audiences. Digital materials are being authored and designed for stand-alone DVD, online interactive sites and archives, an immersive/simulated space for interpretation centres, and augmented/enhanced reality interfaces via GPS and mobile/handheld devices used in situ at key sites.     

基于SBAS-InSAR技术的庆阳北石窟寺区域稳定性监测与分析

区域稳定性监测是石窟寺长期保护的一项重要措施。本研究以庆阳北石窟寺所在区域为对象,基于2019年的15景Sentinel-1A卫星雷达影像,采用小基线集合成孔径雷达干涉测量(SBAS-InSAR)技术对研究区稳定性进行监测,获取了研究区雷达视线向形变速率及时序形变,分析了研究区形变的空间、时间分布规律及其原因。监测结果表明:北石窟寺所赋存的覆钟山山体整体稳定,存在微小形变,不存在潜在滑坡变形特征;研究区主要形变区沿河分布,蒲、茹两河交汇处形变最为明显;研究区时序形变呈现随季节变化的规律性,造成其规律性的原因为随季节变化的土壤侵蚀和董志塬固沟保塬项目的实施。该研究证明了InSAR技术在文物遗址区域稳定性监测的可行性,以及其在具有长期性、可靠性的优势,为石窟寺遗址长期预防性保护提供了新的思路和方法。     

Quarries and transportation routes of Angkor monument sandstone blocks

Sandstone blocks are the main construction materials used in the Angkor monuments in Cambodia. However, a thorough study of the quarries has not yet been carried out. We conducted a field investigation of sandstone quarries from the Angkor period at the southeastern foot of Mt. Kulen, which is approximately 35 km northeast of the Angkor monuments. As a result, we discovered more than 50 sandstone quarries. On the basis of the measurements of magnetic susceptibilities and thicknesses (step heights), we found that they were quarried at different times. These four quarrying areas were identified as the quarries D to G inferred by Uchida et al. (2007). In addition we investigated a canal that was identified on satellite images, connecting quarry sites at the foot of Mt. Kulen to the Angkor monuments. The field investigation suggests a high probability that the canal was used for the transportation of sandstone blocks from Mt. Kulen.     

Radial route systems and agro-pastoral strategies in the Fertile Crescent: New discoveries from western Syria and southwestern Iran

Radial systems of spoke-like pathways, often termed “hollow ways,” are frequently found surrounding mounded tell sites in northern Mesopotamia and have been explained as the product of a particular set of land use practices involving dry-farming agriculture and intensive ovicaprid pastoralism. Yet while similar subsistence strategies were very common across the Near East throughout much of the Holocene, classic hollow ways have only been previously documented in a small region and articulate almost exclusively with sites of the third millennium BC. This paper presents newly discovered hollow ways in western Syria and southwestern Iran, made possible through analysis of an online database of declassified, Cold War-era CORONA satellite imagery. The association of these previously undocumented ancient roads with archaeological sites dating to the Iron Age, Roman/late Roman and early medieval periods, suggests that the land use practices which produced radial route systems may have been quite widespread. Taking into account the wide geographic and temporal distribution of hollow ways, analysis explores various aspects of the agro-pastoral systems that disparate communities may have shared. Results confirm some aspects existing models of hollow way formation, while offering some refinements in terms of the roles that settlement organization, agricultural land use and pastoral strategies play.     

Chalcolithic Hamlet Excavations near Shiqmim,Negev Desert,Israel

Abstract

We explore the nature of three small villages or “hamlets” situated in close proximity to Shiqmim—one of the largest Chalcolithic (ca. 4500–3600 CAL B.C.) settlements in the southern Levant. Located in the northern Negev Desert of Israel, Shiqmim and other large sites in the Beersheva valley have yielded data suggesting the emergence of a regional chief dom-level social organization in this period. Identifying chiefdoms in the Near Eastern archaeological record is difficult because there is little material evidence of displays of rank and power such as are found in Mesoamerican chiefdoms. A two-tier settlement hierarchy with large settlement centers that coordinate religious, political, and economic activities for a constellation of smaller satellite villages or hamlets is one of the most important cross-cultural attributes of chiefdoms documented by anthropologists. The results from archaeological soundings, material culture analyses, and radiocarbon dating of small-scale sites in the vicinity of a large settlement center in the Beersheva valley are consistent with the presence of a dynamic regional chiefdom-level society during the Chalcolithic period.