Archaeologists in the north-west of Western Australia are conducting a survey with a difference at the bottom of the ocean.
The pioneering project is searching for underwater evidence of ancient Indigenous culture in the Dampier Archipelago.
This morning’s ABC News featured the DHSC project team’s recent fieldwork and diving survey campaign in WA. Keep an eye out for more content to appear on ABC news outlets, including radio, online media and ABC iView.
Part 1: Submerged sites
I joined the Deep History of Sea Country (DHSC) project on fieldwork at the island of Hjarnø, Denmark, in June 2018 as a representative of the Queensland Museum Network and James Cook University, both part of the UNESCO UNITWIN Network for Underwater Archaeology. This project was my first opportunity to engage with the fast-growing field of submerged ‘prehistory’. Since entering the maritime archaeology discipline, there have been no previous opportunities to take part in the study of submerged landscape archaeology in Australia. So, I was very excited to have this opportunity to contribute my scientific diving skills to the project, while also learning a great deal about the Mesolithic archaeology of Denmark.
Besides brushing up on my lithic identification skills, I gained experience in excavating a submerged landscape. The excavation in a shallow intertidal environment was very different to the nineteenth-century shipwrecks I have excavated before in Australia, given the diverse site and artefact types. Yet, excavation methods—that is the methods and techniques of underwater archaeology—are the same. Submerged landscape archaeologists add other methods to their toolkits, such as geophysics and coring. Using many sources is like the varied sources adopted by historical archaeologists, such as archival documents and oral histories. Both interdisciplinary approaches allow a more complete picture of the landscape and the way people interacted with it in the past.
As a theorist, I couldn’t help asking the question: are they both maritime archaeology? A lack of exposure to submerged landscape archaeology throughout my education and training and within Australian maritime archaeology (owing to the drivers that led to its development) have led me to associate maritime archaeology with (Western) seafaring. Of course, maritime archaeology is, at its heart, the study of people, culture and their interactions and relationship with the sea through the material and physical remains left behind, preserved through time as archaeological evidence. The definition of maritime archaeology should encompass the entire range of people’s relationships to the seaboard and other aquatic bodies, and their physical and cultural environments.
The location of the submerged landscape we were excavating at Hjarnø was part of an ancient (palaeo- or perhaps meso-maritime) shore at the time of its creation by people archaeologists call the Ertebølle culture. Yet Ertebølle peoples’ intensive exploitation of marine resources must have led to a thorough knowledge of the underwater landscape at that time, such as the location of oyster and cockle beds. Thus, the submerged landscape in the past, though concealed from the peoples of the past, was an integral part of their cognition. Despite the site’s formation on land—and the lack of archaeological evidence of seafaring or nautical technology—the people were still connected to the maritime sphere. The now inundated sites are landscapes of maritime culture and maritime archaeologists must situate it within their remit.
While Australian archaeologists haven’t discovered submerged sites on the continental shelf, the increasing interest and resources in this field, such as the DHSC, will soon provide opportunities for Australian-based students, and early career researchers like me, to learn these skills at home. While I had the advantage of learning these skills firsthand in Denmark—an ideal global training-ground for submerged ‘prehistory’—I cannot call myself a submerged landscape archaeologist. Well, not yet anyway. What I can do is consider myself to be a better, more well-versed maritime archaeologist!
Part 2: Submerged surveys
Fast-forward a year and I have re-joined the DHSC team in Murujuga (Dampier Archipelago), Western Australia, this time as a volunteer. I also have a my new role as a Senior Research Fellow with the University of Southampton, though I maintain an ongoing affiliation with Flinders University as an Adjunct Associate Lecturer. Unlike the Danish fieldwork, the research in Western Australia is searching for prospective areas of submerged archaeology, rather than excavating known sites.
The DHSC team has already spent some time surveying in Murujuga, integrating several aerial and marine survey datasets to refine the diver-based survey strategy. Remote sensing marine geophysical survey included bathymetric lidar and sidescan sonar investigation, in addition to drone-based aerial imagery. Combined with coastal and intertidal surveys, analysis of this data led to the identification of priority areas for diver survey this September.
Using a survey grid with a 20-metre line-spacing has helped to define the survey in a systematic way and will establish whether or not the areas of interest are productive. Using a 100-metre leaded line, buoyed on both ends, diver buddy pairs surveyed the lines and tracked their location with a GPS attached to a dive flag buoy on the reel. With the cameras and GPS mirroring the time, underwater photographs of potential features of interest could later be positioned with accuracy. This survey approach presents an effective and accurate method for searching for submerged landscapes in Australia’s nearshore continental shelf environments, inundated by past sea-level rise.
Being involved in this intensive search for evidence of submerged landscapes in Australia has reinforced the promise of this study area to not only contribute to our understanding of Aboriginal peoples’ adaptation to changing environments in the past, but also to shifting the biases of Australian maritime archaeology. The next generation of archaeology students will be the first to fully embrace these opportunities, and, as an early career researcher, I may now be well on the way toward a fuller, better appreciation for submerged landscape archaeology as a global discipline and indeed, a progressing discipline in Australian archaeology.
Last year our survey team took to the sea aboard the small work boat DAN K (operated by Aust Marine out of Dampier, WA). The team consisted of DHSC staff and research students, based in Adelaide, Perth and overseas. The purpose of the surveys were to complement the data we gathered through bathymetric lidar with sidescan sonar data and identify priority areas for diver survey. The team continued to update the local community Members via the Murujuga Aboriginal Corporation (MAC), who have been involved and updated of our on-going project since the onset.
Sidescan sonar survey allows us to record significant areas of the seabed and view the submarine environment through high-resolution acoustic images. This is important to locate areas of the Dampier Archipelago where submerged cultural material is likely to have preserved so we could characterise the seabed and see what the bottom is made of and what is sitting on the seabed. This will help our divers to select locations to survey later in the project.
Working at sea
Sidescan data collection can be slow going, and is not without its complexities. We need good sea conditions, good weather and the right wind, and good operators. All of the data has to be logged, organised and eventually processed. We had a few false starts early in the year, with technical issues, power problems, and of course bad weather. It took three tries to get it right. But then it all came together.
Our third attempt was the winner. We had 9 consecutive days of calm, beautiful weather last September/October. In that amount of time we could map as many places as we could possibly get to, working 12 hour days at sea, running survey lines back and forth in neat polygons. Hats off to the full time professional marine surveyors who do this for their living year round. They have a seriously challenging job!
We were lucky to have a couple of project team members with such experience and capacity. Francis Stankiewicz, who has previously posted about the Danish component of the project, and Dr Paul Baggaley (Adjunct Lecturer in Maritime Archaeology at Flinders University, and CTO of Wessex Archaeology in the UK). Thanks to a real combined team effort, a bit of luck with the weather, and our hard working crew, we got the data we needed at the survey sites we wanted.
We have now processed the geophysical data and selected target areas for further investigation. The integration of several remote sensing datasets helps to refine our survey strategy, and better understand the submerged environment of the Dampier Archipelago.
DHSC Student Participants: Emma Beckett and Patrick Morrison
Emma Beckett is a PhD student from the Centre for Rock Art Research and Management (CRAR+M) at the University of Western Australia. Her dissertation has been part of the Murujuga: Dynamics of the Dreaming Project directed DHSC CI, Professor Jo McDonald at the University of Western Australia. Emma has also been a student participant in the DHSC project, conducting coastal surveys and flying several drone missions.
In her own words: My research focuses on providing a better understanding of the nature and placement of stone arrangements across the Archipelago. These arrangements come in a wide range of forms adding to an already impressive archaeological landscape and include: standing stones, elongated stones placed upright like spines across the boulder slopes; depressions formed in the rocky hills with stones placed around a central pit and stacks of stones in piles, circles and lines. These stacks are found in a range of environmental contexts across level platforms, hillslopes and within the intertidal zone. These structures represent a range of human activities including the construction of shelter for domestic use and hunting hides, to more easily catch game, establishment of markers likely used for signalling between and within groups as well as the creation of stone arrangements as part of spiritual or religious activities or rituals.
I was delighted to be involved on the most recent Deep History of Sea Country (DHSC) fieldwork in May 2019. I was involved with the recording of coastal terrestrial archaeology so that the team might be better able to understand how this can be identified underwater.
As a GIS specialist, I was heavily involved in the collection and management of the spatial data for this part of the project. I collected aerial imagery from a number of sites using my drone. This processed imagery can be used for the creation of high resolution ortho-imagery and 3D landscape reconstruction.
Drone Image of Enderby Island with DHSC Boat
Being involved in the DHSC fieldwork was really helpful for my own research. I was able to visit and record a number of structures within intertidal areas that I had not been able to access previously. And working with the DHSC team help me gain more experience in understanding coastal landscapes as the various CI’s generously provided expertise, support and resources. Having spent much of the last ten years working in inland arid landscapes, the knowledge shared during the course of this project was invaluable to me.
Submerged stone structure within intertidal zone
This has also been important for helping me further explore the ways in which structures might have played a role for humans as the landscape changed from an inland to a coastal environment. Echoes of the inundation which changed the environment over thousands of years can be imagined even while watching the sometimes dramatic tidal range exhibited in these areas today. Watching the tide swallow up a gently sloping muddy beach in the course of a few hours one can’t help but imagine how people would have reacted as their hunting and foraging range slowly contracted, never to re-emerge.
Thanks to everyone involved in the fieldwork for such a great trip! I am looking forward to further collaboration with the DHSC team in the near future.
Patrick Morrison is midway through his honours project at UWA. He is writing on a stone artefact scatter, found in the intertidal zone of Dolphin Island in Murujuga (the Dampier Archipelago). This site possibly represents evidence for a submerged landscape, inundated by sea-level rise in the Early Holocene and we suspect that this is one of many similar sites in the Archipelago.
Patrick and Emma recording stone tools in the intertidal zone
In his own words: I started formal archaeological training in 2016, after an interesting broadening unit added an Archaeology major to my Neuroscience degree. In that unit, we were introduced to the idea that a third of the Australian continent was inundated by rising seas since the Last Glacial Maximum (around 22 thousand years ago). The implication is profound as some of the most significant archaeological landscapes in Australia remain almost completely unexplored. This includes everything from the first landing sites, the coasts where people lived for the first 40,000 years of occupation, and the Country that remains an important part of many Aboriginal cultures today. When my supervisor Jo McDonald offered me the opportunity to study a potential submerged site, I was delighted.
My involvement with underwater archaeology began briefly before my first archaeology unit. Weekends of scuba diving and an interest in digital technologies came together, and lead to me to join the Maritime Archaeological Association of Western Australia (MAAWA), who were wrapping up an ambitious project using of 3D photogrammetry to record shipwrecks around Perth. I am now the Secretary of MAAWA, where we are running a project on the maritime cultural landscapes in the Swan and Canning Rivers, including everything from shipwrecks, to jetties, and even dumped cars.
Patrick diving on a shipwreck off Fremantle
I was lucky enough to start working on Murjuga in 2017 when I took part in a UWA RTIO rock art field school. More than a million Aboriginal rock engravings reveal a story of human adaptation to sea level rise over many millennia. It is one of the densest rock art provinces in the world, so once we had our eyes in after a few days of recording, we could all see art almost everywhere we looked. Over this last summer, I worked with Jo and the Pawsey Supercomputing Centre as an intern, visualising cultural features on Rosemary Island, one of the larger outer islands of the Archipelago. This gave me a chance to develop my skills in using airbourne LiDAR and drone datasets for archaeology.
The DHSC Team is back in Denmark this month to undertake post-excavation work following the 2018 season of underwater excavation. Preliminary results from our team’s analysis is looking promising!
This follows on the recent #OpenAccess publication in the JICA which was published last month and which describes and discusses the 2017 DHSC Work. That article is freely available via: https://www.tandfonline.com/doi/full/10.1080/15564894.2019.1584135
Keep an eye on the DHSC project blog and our twitter feed for more updates!