Extraction of underwater fragile artifacts: research status and prospect

There are still many difficulties in the recovery and long-term preservation of underwater archaeological artifacts, in situ preservation should be the first choice before further procedures are considered. However, the materials, preservation status, and preservation environment of underwater artifacts are diverse, resulting in many fragile artifacts facing difficult situations. In order to prevent serious damage, it is a safe protective strategy to preserve them in a controlled environment for a long time after excavation. Extraction and transfer of fragile cultural relics are vital parts of this strategy. Due to the complexity of the underwater environment and the vulnerability of fragile artifacts, safety in extraction and transfer still faces enormous challenges. Researchers have developed new materials and technologies to tackle this problem. This paper focuses on introducing and developing prospects to different preservation techniques for fragile artifacts from underwater sites.

Underwater Cultural Heritage in Asia Pacific and the UNESCO Convention on the Protection of the Underwater Cultural Heritage

Underwater cultural heritage (UCH) is a precious part of humanity’s shared history and heritage as it provides vital evidence and information about the interaction of humans with oceans, lakes and rivers. The Convention on the Protection of the Underwater Cultural Heritage was adopted by the General Conference of UNESCO (United Nations Educational, Scientific and Cultural Organization) in 2001 to protect this heritage which has become significantly vulnerable to threats such as pillaging, commercial exploitation and the development of the seabed with the evolution of marine technology in the latter half of the 20th century. The Convention celebrates its 20th anniversary in 2021 and has been ratified by 68 countries. Its annex, which provides rules about the activities directed at UCH, has become a major reference and is recognised as the established scientific standard for underwater archaeology and research today. Despite the growing recognition and application by the international community, the Convention has been ratified only by four countries in the Asia-Pacific region. Many underwater sites and shipwrecks have been commercially salvaged, particularly in Southeast Asia, and numerous artefacts recovered from the sites were often put up for auction, leading to irrevocable damage and loss of this valuable cultural heritage to future generations. This article as one of the themed articles dedicated to the UCH in Asia Pacific argues the roles of the Convention and the challenges and opportunities for the protection of UCH particularly in Southeast Asia. UCH contributes to the achievement of the Sustainable Development Goals and can play an important role in sustainable community and economic development. Its values and importance deserve to be widely recognised and advocated. Efforts for safeguarding cultural heritage in Asia Pacific needs to be pursued and enhanced through joining the 2001 Convention and with international support and cooperation.

Underwater Excavation Records Using Underwater Acoustic Survey: A Case Study in South Korea

The most effective method for surveying underwater archeological sites is visually identifying areas with relics or remains through diving surveys. However, during underwater excavations, it is difficult to obtain images in turbid water. Furthermore, on-site diving is costly and time-consuming. Marine acoustic geophysical survey equipment is not significantly affected by underwater turbidity, and underwater excavations often rely on geophysical equipment for surface inspections. This study aimed to improve existing underwater excavation imaging through the application of acoustic survey methods. Underwater surveys were conducted via acoustic marine geophysical survey devices at three historically significant underwater sites in South Korea: Dangampo, Nakwoldo Island, and the Battle of Myeongnyang. At the Dangampo site, surveys were conducted using three different sonar devices—side scan sonar, multibeam echo sounder, and scanning sonar—and the results were compared; scanning sonar was the most effective. The methodology was further refined during excavations at the Nakwoldo and Myeongnyang sites. Results show that the scanning sonar can produce images that are more accurate than on-site drawings produced during underwater excavations, even in turbid underwater environments. Moreover, applied in conjunction with high-frequency geophysical exploration techniques, scanning sonar can significantly increase the reliability of investigations of buried underwater remains and relics.

Making the Invisible Visible: Underwater Malta—A Virtual Museum for Submerged Cultural Heritage

The seabed can be considered as the world’s largest museum, and underwater sites explored and studied so far provide priceless information on human interaction with the sea. In recognition of the importance of this cultural resource, UNESCO, in its 2001 Convention on the Protection of the Underwater Cultural Heritage, determined that objects/sites should be preserved in situ, whilst also advocating for public access and sharing. The implementation of these principles is not without difficulties. Some states have opened up underwater sites to the public—mainly through diving, yet the vast majority of the world’s population does not dive. In Malta, 7000 years of human occupation is reflected in and on the landscape, and recent offshore surveys show that the islands’ long and complex history has also left an indelible mark on the seabed. Besides difficulties related to their protection and management, these sites also present a challenge with regard to sharing and communicating. Recent advances in underwater imaging and processing software have accelerated the development of 3D photogrammetry of submerged sites and the idea for a virtual museum was born. The virtual museum, UnderwaterMalta, was created out of a need to share the plethora of underwater sites located on the seabed of the Maltese Islands. A multitude of digital tools are used to share and communicate these sites, offering visitors a dry dive into submerged sites that would otherwise remain invisible to the vast majority of the public. This paper discusses the basic principle of the sharing of underwater cultural heritage and the difficulties that beset the implementation of such a principle. A detailed explanation and evaluation of the methods used to gather the raw data needed is set in the context of the particular and unique working conditions related to deep water sites. The workings of this paper are based on first-hand experiences garnered through the recording of numerous wrecks over the years and the creation and launch of The Virtual Museum-Underwater Malta—a comprehensive virtual museum specifically built for “displaying” underwater archaeological sites that are otherwise invisible to the general public.

Digital Technologies for the Sustainable Development of the Accessible Underwater Cultural Heritage Sites

In recent years, the development in digital technologies such as Augmented Reality (AR) and Virtual Reality (VR) has evolved rapidly. These technologies are currently in the process of creating driving change in the Cultural and Creative Industries (CCIs), representing innovative means to share information, facilitating access and increasing the value and public awareness on Cultural and Natural Heritage. This is particularly relevant for underwater environments, where the most interesting cultural and naturalistic sites are accessible only to scuba divers, or not accessible at all, due to depth and/or environmental constraints. In addition, in underwater sites, guided diving tours are carried out by professionals that usually describe the area to be visited during the predive briefings; such step is needed due to the impossibility of underwater verbal communication without dedicated equipment, a practice very rarely adopted for recreational diving. So, these difficulties make it almost impossible to replicate under the sea, the guided tour approach that is usually offered in on-land museums. Considering such limitations, several technological applications are emerging to increase the accessibility underwater and enrich users’ experience both for divers and nondivers. This work aims to identify the potential of underwater sites (either cultural or natural) to support the development of sustainable tourism (economic, environmental, cultural and social) in the Mediterranean. Moreover, it focuses on supplying local/regional authorities and stakeholders with a multidisciplinary plan for managing Underwater Museums and Knowledge Centres, by promoting innovation in the diving industry and improving users’/tourists’ experience through value-added services and cutting-edge technologies.

Reconstructing a Submerged Villa Maritima: The Case of the Villa dei Pisoni in Baiae

Among the activities planned for the MUSAS Project, the digital reconstruction of the underwater sites constitutes a particular challenge, requiring strong cooperation between archaeologists and technicians. The case of the Villa dei Pisoni in Baiae, one of the richest in the Phlaegrean territory, is particularly interesting: the architectural remains, already documented in the 1980s and now inserted in one of the diving spots of the Underwater Park of Baiae, are disseminated on a huge surface, including quays, thermal complexes, a fishpond, and a large, luxurious viridarium. The effort required for the digital reconstruction of the ancient villa improved the previous knowledge and the lack of documentation even in a well-known site. In this paper, we will retrace the long path from the 3D reconstruction of the archaeological remains to the virtual architectural model of the villa, the numerous challenges, doubts, and uncertainties in the creation of the original spaces, and the support offered by the ancient sources, both literary and iconographic, in solving archaeological problems.

Challenges for the Protection of Underwater Cultural Heritage (UCH), from Waterlogged and Weathered Stone Materials to Conservation Strategies: An Overview

Despite the growing attention to Underwater Cultural Heritage (UCH) in Europe and worldwide, the efforts in wholly enjoying underwater archaeological assets and sites are still remarkable; hence, the need for innovative research and solutions that are suitable for raising knowledge on the subject. In this way, this paper wants to be a review for highlighting all of the developments, potentials, and results achieved in the last decade to reach a good protection of UCHs related to the study of stone materials, degradation processes, and the new methods for protection/consolidation directly in situ. The present work is focused on the analysis of the main results obtained from several studies conducted to date, providing additional guidelines for operators in the UCH sector (i.e., restorers, archaeologists, conservation scientists, geologists, etc.). Such guidelines will be a very useful key factor in enhancing knowledge, management, protection, and promotion of underwater sites. In particular, the purpose of this paper is to provide an analysis of the state of the art on both consolidated techniques for studying materials coming from seawater and innovations in the field of protection and consolidation of UCH against biofouling, the main cause of damage in underwater environments.

VirtualArch: Making Archaeological Heritage Visible

Rapid technological development in recent years means that virtual reconstructions have evolved from an illustrative complement of archaeological presentation to becoming a standard part of the interpretative process of archaeological data. VirtualArch has been employed to develop the use of virtual reconstructions as an innovative visualisation tool. Ten partners from eight countries have come together in an EU-funded project (Interreg Central Europe), running from 2017 to 2020. The partnership comprises regional and national archaeological institutes and heritage offices, two universities/research institutions and also two local communities. Eight pilot sites have been selected across Central Europe with three main types; urban areas, mines and underwater sites. All have one thing in common; none are publicly accessible or visible. The aim of the project has been to make all of these sites accessible and comprehensible through the use of virtual and augmented reality. This article summarises the project and its outcomes.

PENELITIAN DAN PENGEMBANGAN SITUS ARKEOLOGI BAWAH AIR DI KALIMANTAN (RESEARCH AND DEVELOPMENT OF UNDERWATER ARCHAEOLOGICAL SITES IN KALIMANTAN)

Kondisi lingkungan fisik Kalimantan yang terdiri atas dataran rendah berawa dan hutan lebat menyulitkan akses jalan darat. Puluhan sungai besar dan ribuan sungai kecil membelah daratan Kalimantan, sehingga sungai merupakan alat transportasi utama di Kalimantan sejak zaman prasejarah hingga pertengahan abad ke-20 Masehi. Migrasi, ekspedisi militer, penjelajahan, penelitian, kegiatan misionaris, dan perdagangan, dilakukan dengan menggunakan kapal atau perahu menyusuri sungai besar hingga anak-anak sungai ke arah pedalaman. Dalam perjalanannya, banyak kapal/perahu yang mengalami masalah di perjalanan hingga akhirnya tenggelam dan kini menjadi benda yang mengandung nilai penting bagi sejarah dan pengetahuan. Artikel ini bertujuan untuk mengetahui apa saja situs tinggalan bawah air di Kalimantan yang sudah diteliti serta bagaimana upaya pelestarian dan pengembangannya. Artikel ini menggunakan metode penelitian deskriptif interpretatif dengan penalaran induktif. Data yang digunakan merupakan hasil penelitian Balai Arkeologi Kalimantan Selatan pada tahun 1997, 2006, dan 2012 yang dilakukan dengan metode survei dan ekskavasi. Ada tiga objek bangkai kapal tenggelam yang pernah di teliti oleh Balai Arkeologi Kalimantan Selatan, yaitu kapal dagang Belanda di Sungai Martapura Banjarmasin, kapal Onrust di hulu Sungai Barito, dan bangkai kapal di Sungai Kapuas Kalimantan Tengah. Penelitian arkeologi bawah air terkesan berhenti, sedangkan pelestarian dan pengembangan ketiga objek kapal tenggelam itu hingga kini masih sebatas wacana. Tidak optimalnya penelitian dan pengembangan hasil penelitian karena keterbatasan sumber daya manusia yang fokus ke arkeologi bawah air, serta kurangnya koordinasi antara Pemda dan stake holder untuk pelestarian dan pengembangannya. Wacana pengangkatan kapal tenggelam penting segera ditindaklanjuti, terutama yang bernilai sejarah untuk dimanfaatakan sebagai objek wisata dan bukti perjuangan nenek moyang. Kalimantan's physical environmental conditions are consisting of lowland marshy and dense forests,it make difficult to be accessed by roads. Dozens of great rivers and thousands of small rivers divide the mainland of Borneo, so the river is the main means of transportation in Borneo since prehistory times until the mid-20th century. The migrations, military expeditions, exploration, research, missionary activities, and trades were carried out by boat/ships down the great river to the small rivers to inland. In its journey, many boats or ships are having trouble on the way until it finally sank and now become objects that contain important values for history and knowledge. This article aims to find out what Borneo underwater sites have been studied and how to conserve and develop them. This article uses descriptive interpretive research method with inductive reasoning. The datas used are the archaeological reaserches of Balai Arkeologi Kalimantan Selatan in 1997, 2006, and 2012 conducted by survey and excavation method. There are three shipwrecks have been researched, that are in the Martapura River Banjarmasin, Onrust ships in the upstream Barito River, and shipwrecks in the Kapuas River Central Kalimantan. The research of underwater archaeology seems as if stoped, while the preservation and development of these three objects of shipwrecks are still the discourse. The research is not optimal due to the limited human resources whose focus on underwater archeology, and the lack of coordination between the local government and the stakeholders for its preservation and development. The discourse on the appointment of shipwrecks must be followed up immediately, especially those which have historical values to be used as tourist objects and monuments of ancestral struggle.