Laser scanning for the documentation and management of heritage sites within the Emirate of Fujairah,United Arab Emirates

The Emirate of Fujairah in the UAE has many important cultural and archaeological sites. These include the Fujairah and Al‐Bithnah forts and the Al‐Bidyah Mosque. With increasing tourism patronage and development of major infrastructure projects in and around Fujairah, these sites are increasingly under threat. Their present condition requires careful mapping for proper management and future preservation efforts. This paper presents a research project that is developing a method for surveying and recording important archaeological sites. Using terrestrial laser scanning (TLS), a number of surveys were undertaken in and around the emirate. These surveys enabled a documentation of their present condition and will form an ongoing baseline study to monitor the impact of increased tourist patronage and climate change at these sites. We also investigate and make basic comparisons between our approach and the Structure from Motion (SfM) technique.     

Three-dimensional recording by laser scanning of the petroglyphs at Rombald's Moor,West Yorkshire

Abstract

A variety of methods have been used to depict and document petroglyphs, from hand sketching to close-range photogrammetry. Most methods, however, record only a two-dimensional image, whereas petroglyphs are by their nature three-dimensional. Additionally, most methods suffer from inaccuracies resulting from the skill and subjectivity of the recorder or distortions imposed by the equipment and conditions under which the panel was viewed. Conventional three-dimensional recording techniques such as the use of traditional moulding and casting materials, may damage the petroglyph itself. An assessment of the various shortcomings of established rock art recording methods resulted in the field-testing of laser scanning with the objective of obtaining a quantitative, three-dimensional record of petroglyph panels and the creation of non-contact replicas. This paper presents the principles behind laser scanning and an account of field trial results of laser scanning rock art in situ at Rombald's Moor, West Yorkshire, England. The work presented was undertaken as part of the Rock Art Pilot Project commissioned by English Heritage in July 1999.     

三维激光扫描在文物考古中应用述评

对文物和遗址遗存进行精确描述和测绘一直是文物保护和考古发掘工作中的一个重要内容。相较于传统测绘方法,三维激光扫描具有快速、准确、无需接触文物表面等优势,已被广泛采用于文物保护和考古发掘工作中。本文对三维激光扫描的原理和工作流程进行简要介绍,并对其近期在文物保护和考古工作中的应用情况做出综述和评论。     

Identification of fossil hairs in Parahyaena brunnea coprolites from Middle Pleistocene deposits at Gladysvale cave,South Africa

This research focuses on scale pattern and cross sectional morphology of hair to identify an expanded sample of fossil hairs from Parahyaena brunnea coprolites from Gladysvale cave in the Sterkfontein Valley, South Africa. The coprolites are part of a brown hyaena latrine preserved in calcified cave sediment dated to the Middle Pleistocene (257–195 ka). Forty-eight fossil hairs were extracted from 12 coprolites using fine tweezers and a binocular microscope, and examined using a scanning electron microscope. Hair identification was based on consultation of standard guides to hair identification and comparison with our own collection of samples of guard hairs from 15 previously undocumented taxa of indigenous southern African mammals. Samples were taken from the back of pelts curated at the Johannesburg Zoo and Ditsong National Museum of Natural History (formerly Transvaal Museum, Pretoria). Based on the fossil hairs identified here, this research has established that brown hyaenas shared the Sterkfontein Valley with hominins, warthog, impala, zebra and kudu. Apart from humans, these animals are associated with savanna grasslands, much like the Highveld environment of today. These findings support the previous tentative identification of fossil human hair in the coprolites, provide a new source of information on the local Middle Pleistocene fossil mammal community, and insight into the environment in which archaic and emerging modern humans in the interior of the African subcontinent lived.     

激光清洗架上绘画研究综述

本工作从应用的激光类型、激光对主要画材的影响以及清洗表面沉积物、处理老化光油、去除复绘和清洗画背等主要应用场景等层面,系统呈现了激光清洗架上绘画的研究现状,为实际应用中激光类型等工艺参数的选择提供了全面的参考,给出了典型的工作逻辑与流程,同时也指出了现有研究中的空白和不足。     

三维激光扫描技术在岩土文物保护中的应用

三维激光扫描是近年来飞跃发展的一项高新测绘与信息技术,在文物保护中发挥了重要作用介绍了三维激光扫描技术的主要特点,从岩土文物保护需求出发,结合实际文物保护工程,重点介绍了三维激光扫描技术在文物信息留存、虚拟修复、监测等方面的应用,最后指出三维扫描技术在岩土文物保护中的心用与发展须与保护需求紧密结合,而硬软件的改进完善及相关技术的集成心用亦是重要研究方向。     

Three-dimensional laser scanning: potential uses for museum conservation and scientific research

Recent technological advancements have made a tremendous impact in the fields of biological anthropology and archaeology. Although advancements in DNA analysis have overshadowed other areas of progress in the subfields of biological anthropology, bioarchaeologists are now utilizing many other new forms of technology in their work. In particular, three-dimensional (3D) laser scanning offers a sophisticated method of documenting and studying prehistoric human skeletons. In recent years, portable laser scanning devices capable of creating high resolution images have become available, enabling researchers to scan and archive skeletal collections from archaeological sites and museum collections around the world. 3D laser scanners are inexpensive, simple to operate, and completely non-destructive to human skeletal material. A major benefit is that they offer a cost-effective method of creating a digital record of skeletal collections for museum archives. Since published research using 3D methods typically focuses on sophisticated analyses used to analyze 3D data that are difficult for the novice user to follow, in this paper we provide a simple and straightforward overview of 3D scanning methods aimed at non-specialists. We discuss how these methods can be used to preserve and document osteological material in museums, develop research ideas in the subfields of biological anthropology, and increase the potential for scholarly collaboration.     

The spiral that vanished: the application of non-contact recording techniques to an elusive rock art motif at Castlerigg stone circle in Cumbria

This article describes the recording of stone 11 of the Castlerigg stone circle in Cumbria through two different non-contact techniques: laser scanning and ground-based remote sensing. Despite the unproblematic recording of modern graffiti, neither technique was able to document the spiral photographed and rubbed in 1995. It is concluded that the spiral was most probably painted and has since faded away due to natural events. The discovery and loss of the spiral motif in Castlerigg is seen as a cautionary tale. In particular, it seems to suggest that it is time to take advantage of the novel technologies based on the digitisation of 3D surfaces with millimetre and submillimetre accuracy such as laser scanning and ground-based remote sensing. They offer many advantages to the recording of prehistoric carvings. In addition to avoiding direct contact with the rock surface eliminating the preservation concerns raised by other techniques, both produce high quality images (laser scanning offering a greater potential for this, but at higher cost) having a much higher level of objectivity, and precision and accuracy far beyond those of traditional recording methods such as wax rubbings and scale drawings.     

关于青铜文物深层有害锈形成与转化的分析研究

为了长久保存馆藏青铜文物,有效转化深层有害锈氯化亚铜,以仿古青铜试样为对象,应用循环伏安法、恒电位极化法等电化学实验来研究青铜在模拟中性土壤介质溶液中的电化学行为,应用X-射线衍射(XRD)、共聚焦激光Raman显微分析检测其腐蚀产物的主要物相。结果表明,氧化过程是生成有害锈氯化亚铜的反应,还原过程是氯化亚铜还原成铜的反应。运用扫描电子显微镜和能谱仪(SEM-EDS)进行形貌观察和微区腐蚀产物成分分析。对氯化亚铜在不同湿度环境下的变化进行了跟踪观察。由此,为除去青铜文物深层有害锈氯化亚铜所做的一系列探讨将在博物馆藏品保护方面具有一定应用价值。     

From Boatyard to Museum: 3D laser scanning and digital modelling of the Qatar Museums watercraft collection,Doha, Qatar

This article presents the results of a project to 3D laser scan and digitally model 14 watercraft from the Qatar Museums collection, comprising a range of regional vessels: most had not been surveyed previously. The project used the resulting point clouds generated 2D naval lines and orthographic records of the vessels in their current condition, and photorealistic 3D digital models for gallery display. This case study provides illustrative examples of the intermediate stages and final outputs. It assesses the pros and cons of 3D laser scanning as a survey technology for nautical scholars in terms of the time, cost, and skillset, as well as logistical considerations. It also compares the accuracy of traditional hand survey methods.     

New tools for rock art modelling: automated sensor integration in Pindal Cave

This paper presents the integration of automated sensors based on a terrestrial laser scanner and an amateur digital camera with the aim of generating a photorealistic three-dimensional (3D) model of the Principal Panel in Pindal Cave (Spain). The approach developed for 3D modelling overcomes many of the problems related to the independent implementation of photogrammetry and laser scanning. Particularly, a sequential and hierarchical approach was developed based on the processing and matching of images from the camera (camera image) and the laser scanner (range image). The results obtained demonstrate that the workflow for this model is automatic, effective, and accurate. The presented approach was found to create hyper-realistic models, even improving upon human visual capabilities.     

Laser scanning confocal microscopy: a potential technique for the study of lithic microwear

The key problem restricting lithic microwear analysis is the lack of quantitative analysis to support qualitative assessments of different wear traces. This paper presents the reflective laser scanning confocal microscope (LSCM) as a new technique for the study of lithic microwear that has the potential to resolve this problem. Firstly, an example is presented that shows how the LSCM compares with conventional reflected light microscopy and scanning electron microscopy. This shows that images, rivalling that of the SEM, can be produced in similar timescales to conventional photomicrography and with no need for casting or sample preparation. The LSCM is also used to measure surface roughness of use-wear produced from working hide (dry, fresh and greasy), woodworking and antler working. This analysis demonstrates clear differences between the different wear polishes and the potential of the LSCM as a quantitative approach in lithic microwear research.     

A new approach to recording and monitoring wet-preserved archaeological wood using three-dimensional laser scanning

The analysis and preservation of organic materials preserved within wetland environments represents one of the most costly parts of any post-excavation strategy. This paper outlines the application of high-resolution terrestrial laser scanning to one class of preserved material, worked archaeological wood. Scanning allowed the recording of the artefacts in three dimensions and the identification of features such as toolmarks. Features can be measured and volumetrically modelled within the digital environment, which may not always be possible for these often fragile materials using conventional techniques. Repeat scanning of the artefacts provided an opportunity to use comparative analysis software to investigate changes in the morphology of artefacts under contrasting conditions of short-term storage. The results suggest that immersion in water results in the least deterioration, whereas both freezing and air-drying caused distortion and degradation. This paper demonstrates that laser scanning provides a viable alternative post-excavation method for the recording, analysis and long-term ‘virtual archiving’ of organic archaeological materials, which may be more cost-effective in some instances than other methods of preservation.     

Early Human Decapitation, 11,700–10,700 cal bp,within the Pre‐Pottery Neolithic Village of Tell Qaramel,North Syria

The process and timing of skull removal remains poorly understood by researchers. New archaeological and skeletal analysis from two skeletons from the early Pre‐Pottery Neolithic site of Tell Qaramel, northern Syria, highlights that Neolithic villagers used stone tools to physically decapitate the dead. Drawing upon cutmarks on the axis and the mandible from primary and secondary burials, we employed a scanning electron microscope to document how Neolithic people cut the ligament and its surrounding connecting tissues that bind the cranium with the bones of the axis and the mandible. The position of the cutmarks, especially at the top of the odontoid process of the axis, illustrates the complexities of intentional skull removal. From these and associated burial data, we illustrate that Levantine Neolithic people had specific practical codes for the sequence of skull removal, but given variation in the decomposition of the human body, at times, villagers had to use flint tools for skull removal. This study provides evidence of some of the world's earliest examples of intentional decapitation within human communities. Copyright © 2013 John Wiley & Sons, Ltd.     

Probable human hair found in a fossil hyaena coprolite from Gladysvale cave,South Africa

Until now, the oldest known human hair was from a 9000-year-old South American mummy. Here we report fossil hairs of probable human origin that exceed that age by about 200,000 years. The hairs have been discovered in a brown hyaena (Parahyaena brunnea) coprolite from Gladysvale cave in South Africa. The coprolite is part of a hyaena latrine preserved in calcified cave sediment dated between 195,000 and 257,000 years ago. This find supports the hypothesis that hyaenas accumulated some of the early hominin remains found in cave sites, and provides a new source of information on Pleistocene mammals in the Sterkfontein Valley.     

A HYBRID APPROACH TO CREATE AN ARCHAEOLOGICAL VISUALIZATION SYSTEM FOR A PALAEOLITHIC CAVE

This paper presents a visualization system based on metric data to manage and disseminate archaeological information on the Internet. We describe the integration of two different types of sensors: laser scanning and close‐range photogrammetry. How we created an automatic and hierarchical approach based on processing and matching the images coming from a digital camera and a terrestrial laser scanner is also shown. This development has created a visualization system combining spherical photographs and georeferences for graphical and numerical data acquired by the sensors. The case study where we have applied this method is the Palaeolithic rock art of the Llonín Cave (Asturias, Spain), which has been declared a World Heritage Site by UNESCO and has restricted public access. Our results demonstrate that this tool integrates data, metadata, services and information, which simplifies the location, identification, selection and management of archaeological information.     

多时相三维激光扫描技术在考古发掘过程中的应用——以江苏孔塘遗址为例

三维激光扫描技术凭借快速、准确、无需接触文物表面等优势,已被越来越多地应用于文物保护和考古发掘工作中。江苏句容孔塘遗址在发掘过程中运用三维激光扫描技术不断跟进扫描,全面真实记录发掘过程中的各类遗迹的空间数据。在顾及遗存特征的前提下,对多时相墓葬点云数据进行了空间匹配、分割和缺失数据拟合等后期处理,重建遗址三维场景,直观展示多期遗存的时空关系,为后期考古研究推理提供了数据支持。     

三维激光扫描技术在土遗址保护中的应用——以隋唐洛阳城定鼎门遗址唐代道路遗址保护为例

在隋唐洛阳城定鼎门遗址唐代道路遗址保护中,运用三维激光扫描技术完整地收集了遗址表面的形貌信息,并建立了相关数据库。以此为例,说明三维激光扫描技术在土遗址保护中的作用和意义。     

NEW EVIDENCE FOR THE NATURE OF THE ATTIC BLACK GLOSS

New evidence is reported here using transmission electron microscopy, scanning electron microscopy, and laser reflectance for the nature of the black glossy decoration layer present on the Attic black or red figure vases of the sixth to fourth century BC. The black layer, of total thickness about 20 μm, consists mainly of poly crystalline magnetite (Fe₃O₄) particles of dimensions from 0.2 μm down to extremely fine sizes embodied in an amorphous vitreous matrix. On the outer surface of the black paint we discovered for the first time a thin clear glassy film of approximate thickness 0.1 μm which is rich in Al and Fe and poor in Si. This film must be responsible for the characteristic sheen of the surface. This is verified with the reflection of laser light mostly in specular direction, a unique property compared with black paints of other areas and other periods.     

试论数据采集与虚拟修复在大足石刻修复中的应用

文物作为一种不可再生的宝贵资源,其本体上的保护修复工作均需慎之又慎,需遵循国际上规定的“最小干预”及“可逆性”基本原则.为此,虚拟修复成为对文物动手修复时的重要辅助手段.然而,多数文物具有复杂立体结构和色彩,传统的虚拟修复技术难以实现逼真效果.三维激光扫描是近年来飞跃发展的一项高新测绘与信息技术,具有无损、空间精度高、速度快等突出优势,在文物数字留存及相关保护应用中发挥了重要作用.三维激光扫描技术与高清摄影技术相结合,为文物的虚拟修复带来新的契机.本文结合文物虚拟修复基本需求分析,提出了基于三维激光扫描技术的文物虚拟修复关键技术与工作流程,并以国家一号石质文物保护工程——大足石刻宝顶山千手观音造像的保护修复为例,进行了应用实践,综合历史资料和现有数据的分析,实现了三维形态及色彩的虚拟修复.结果表明,基于三维扫描的虚拟修复能够提供更为逼真的三维虚拟修复模型,供修复专家研究参考.