Wednesday, March 20, 2013

Plans and Profiles: Kieran Westley Researching Submerged Landscapes North of Ireland

Kieran Westley with a rather nice flint
blade found about 2m underwater
(photo taken by Wes Forysthe)
Kieran Westley is an archaeologist with the Environmental Sciences Research Institute at the University of Ulster who specializes in Maritime Archaeology, especially reconstructing and surveying submerged landscapes.  He completed a Post-Doc at Memorial University following the completion of his PhD at the University of Southampton.  No matter where you are in the world, the sea level has changed over time.  This change happens as the earth's crust moves up or down and water is added or removed to the world's oceans through melting or freezing of water in polar ice caps or continental ice sheets which causes coastlines to erode or be built up.  In Ireland, the earliest coastal sites have been inundated by rising relative sea level.  These are the sites that Kieran is looking for...

Plans and Profiles #14. Kieran Westley, Submerged Coastlines and Archaeological Sites north of Ireland


1) Tell me a little bit about your project.


Rough palaeo-geographic reconstruction showing the 
north of Ireland assuming a sea-level fall of -30m 
which could have taken place as early as 13,500 cal BP. 
The project involves attempting to identify, map, reconstruct and sample submerged archaeological landscapes in the north of Ireland. We're looking at submerged landscapes because sea-levels around Ireland were lower during its earliest known colonization - the early Mesolithic (dated to around 10-9500 cal BP). We know that these early colonists needed at least some sort of maritime adaptation to get to Ireland because the available sea-level evidence suggests that it was separated from mainland Britain at this time despite the lowered sea-level. In addition, worked flints have also been found on at least one outlying island which were also not connected to Ireland and hence would have needed watercraft to get there. However, probably due to sea-level rise, we have very little evidence of these coastal/maritime adaptations onshore, and therefore have to look for it offshore. An additional reason for researching these submerged landscapes relates to cultural resource management. We're seeing increasing development of the continental shelf; for example, cables, pipelines, offshore wind turbines etc. All of these activities have the potential to damage or destroy the undersea archaeological record. Therefore, in order to manage and protect these archaeologically important submerged landscapes, we need much more information on where they are located and preserved. In other parts of NW Europe, submerged landscapes are much better studied, for example in the Baltic and the North Sea; however, Ireland really remains a blank slate as far as this type of research goes.

Intertidal peat layer exposed on the beach at Portrush West Bay
The actual methodology involves two strands. Firstly, large-scale mapping and reconstruction of submerged landscapes using marine geophysical data. These include high resolution multibeam sonar systems which map seabed topography and substrate, and sub-bottom profiling systems which give acoustic cross-sections through the seabed allowing us to map buried layers. Secondly, a program of diver survey to ground-truth potential submerged landscape features, and identify archaeological remains.

So far, we’ve used the data to create rough approximations of palaeo-geography, and identify high potential areas where the palaeo-landscape has been preserved. These have formed the basis of our program of diver survey. Three main sites with palaeo-landscape evidence have been investigated so far. Firstly, a probable wave-cut rocky shoreline west of Ballycastle in c. 12 to 15m water depth. While features like this provide a nice indication that sea-levels were lower, they unfortunately can’t be dated directly. Secondly, a buried and submerged peat layer in the West Bay Portrush, in at least 3m water depth which extends off a thick layer of intertidal peat which is occasionally exposed when storms strip away the beach sand. We’ve traced this peat offshore with sub-bottom profile data and sampled it to get a date of c. 8900-9200 cal BP. Finally, another submerged peat (which has been dated 8700-9400 cal BP) and a small concentration of worked flints (which include distinctive early Irish Mesolithic forms) in c. 2-3m water depth are also under investigation. These come from two small adjacent bays (the flints in one and the peat in another) in Eleven Ballyboes townland, County Donegal. The bay with the flints has a collection of around 1500 water-rolled intertidal lithics amassed by a local collector, but the underwater finds we’ve made in the last year include much fresher examples and could therefore represent the remnants of an in situ source deposits More work confirming this and also investigating the submerged peat for palaeo-environmental and archaeological evidence will hopefully happen this coming summer.

Possible wave cut rocky shoreline at -13 to -15m depth west of Ballycastle (bathymetric data collected by the JIBS project, terrestrial aerial photo and DEM courtesy of LPS)


2) How did you become interested in this particular problem?

I've been interested in submerged landscapes since my undergrad days. What first piqued my interest was the colonization of the Americas involving the now submerged Beringian landbridge and the possible coastal route down the western coast of the US and Canada. Consequently, I went to Southampton University to do a masters and then PhD focusing on maritime archaeology and submerged landscapes. Most of my research since has therefore had some sort of a submerged landscapes component. The reason for looking at the north of Ireland is a little more pragmatic. Firstly, I got a job there (at the Centre for Maritime Archaeology, University of Ulster) and secondly, a very large quantity of seabed mapping data for the Irish coast was made available, giving archaeologists a chance to actually visualize the seabed in unprecedented detail.


3) Has your project changed since you originally began working on it? How?

Some of the intertidal lithics collected from Eleven Ballyboes
There have definitely been changes. When we started, it was intended that we would follow a nice 7 stage methodology devised by Trevor Bell at the MUN Geography Department. This essentially aimed to collect data on the seabed and sub-seabed, use this to create a detailed palaeo-landscape reconstruction and then apply predictive modelling of archaeological site locations to target ground-truth surveys. However, once we got going, we found that while the individual stages were great, sticking to a rigid structure was actually quite difficult, since some stages relied on data which was not available at the time, while we could make a head start on other stages where data was available. A good example of this is our work on the Eleven Ballyboes site – we targeted the site because it had lithics which appeared to be washing ashore and were therefore able to skip the predictive modelling stage.

This type of research is also massively interdisciplinary and really dependent on help from colleagues (most notably Ruth Plets, Rory Quinn and Peter Woodman, but also with help from individuals too numerous to mention). Dive surveys also require a team (thanks to Rory McNeary, Wes Forsythe, Colin Breen and the NERC Facility for Scientific Diving) and often boat support. It’s often the nature of research projects that people move on, get involved with other research projects or take on new jobs. For example, I personally had to put aspects of it on hold while I undertook research on the impact of coastal erosion on behalf of the Northern Ireland government heritage agency. Between this and my colleagues’ other commitments, the project has moved from a full time exercise to something a little more ad hoc, which is a shame, but is sometimes the reality of research.


4) If you had a time machine and could present your research to the people who lived at your site(s) – what would you hope their response would be?


Intertidal test pitting at Eleven Ballyboes  (or how many 
archaeologists does it take to dig a 1 x1…) 
(photo taken by Rory McNeary)
I’d hope that they’d be interested in how much the landscape was changing because of sea-level rise. It’d be really interesting to know the extent to which they actually perceived the change in sea-level and whether they thought it was a good or bad thing. Also, I would hope that they would then tell me where they’ve left all their coolest stuff.


5) Has your research taught you anything about yourself? What? 

That persistence pays off, and that you never know as much as you think - there’s always something more to learn.


Diver sampling the Portrush peat layer (buried under 
the sand) with a small hand core
6) I can’t imagine doing this research without...

Dive gear obviously and lots of lovely geophysical data.


7) How do you unwind when you need to get away from your research?

Beer, televised sport and Call of Duty on the Nintendo Wii (though not necessarily in that order).


8) Do you have any advice for students just starting out in Archaeology?

Archaeology is a tough field to stay in – take every opportunity you get to build up different skills and experience. You never know which might come in handy.



Sample of fresh lithics from underwater
versus water-rolled ones from the
intertidal beach. The fresh ones tend
to be grey or blue-grey, while the
rolled ones are patinated yellow, red,
orange or light grey.
9) What books or websites would you recommend if people want to learn more about your area of interest in general? Or your project in particular?

Our project has its own (infrequently updated) blog: Submergedlandscapes. This has lots more information on the project and the sites I mentioned earlier. More widely, SPLASH-COS (Submerged Prehistoric Landscapes and Archaeology of the Continental Shelf) is a Europe-wide networking project. There’s a webpage (http://www.splashcos.org/ ) and a Facebook Page . These have links to other projects including ongoing research and meetings. For the books – go for the recent volume Submerged Prehistory by Jonathan Benjamin et al. (2011). This is an edited volume with research papers from across the world. It’s a really nice introduction which showcases the breadth of current research in the field.

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Do you have research that you'd like to share with other arcaheologists or do you know a student or colleague whose work should be highlighted?  Send me an e-mail: elfshot.tim@gmail.com

Photo Credits: 
Kieran Westley, unless otherwise noted in the captions.
Plans and Profiles Banner, Tim Rast based on a linocut by Lori White

1 comment:

  1. I think the work that Kieran and his colleagues is doing is really interesting and important. I think readers of this blog would also be interested in an article that Kieran co-authored back in 2008 that takes a critical look at the North Atlantic environment during the hypothesized movement of people from Europe to North America. Its very enlightening.

    Westley, Kieran and Dix, Justin (2008) The Solutrean Atlantic Hypothesis: A view from the ocean. Journal of the North Atlantic, 1 (1). pp. 85-98.

    http://www.bioone.org/doi/abs/10.3721/J080527

    ReplyDelete

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