Cardigan Bay Mesolithic Landscapes Re-visited
Combining work with fun is a common theme on many of these pages and so my latest travels are once again in that vein. A few years ago we undertook a small seismic sub-bottom survey in Cardigan Bay to see what the potential was for mapping buried and submerged land surfaces. In a similar situation to Doggerland, the west coast of the UK also hides secrets of past landscapes that our early ancestors used. Mapping these however has been at a slower pace than in the North Sea mainly due to the lack of hydrocarbon exploration data and more recently the slower uptake of offshore wind. Research undertaken by Aberystwyth University (Rob Wittington et al) and the BGS does give us some clues to the situation through sub-bottom records and some deep boreholes.
Our data from 2018 With the Irish Marine Institute and the Celtic
Explorer identified a complex landscape from which I was able to speculate
on a series of possible geographical models for the time periods from early
Mesolithic to today (in press, Europe’s Lost Frontiers: Vol II).
 |
Coastal geographies and positions of major river and associated
archaeological sites. A: Early Mesolithic, 10,000 cal yrs BP. Sites 0:
Aberdaron; 1: Pencilan Head; 2: Y Bryn; 3: Afon Wen; 4: Aberystwyth; 5: New Quay; 6:
Newport; 7: Pencaer. |
These models were based on the limited seismic data that we had
acquired, the old seismic data and some limited boreholes. Using the boreholes
I created a function to adjust the present day bathymetry with the seismic
mapped river/estuaries and a different function for the land that fell between
them. Sarah Boyd provided palaeo-sealevels
from PhD research and tidal regimes were derived from the work of James Scourse. Armed with these we now needed to test
against new seismic and ground truth data.
Teaming together with Dei Huws from Bangor Uni we used a sub-bottom profiler to acquire new data during a particularly calm period in late May. We used the 13m ketch Ivilia for the survey and she proved a stable platform for 24hr ops.
New survey lines were acquired north of Aberdovey down to NewQuay. The fidelity of the sub-bottom data was far
higher than the earlier information from the Celtic Explorer but the major
horizons match nicely. The major palaeo-channels that parallel the coast
offshore were confirmed and showed more complexity than we had originally been
able to see. As always, the more you
look, the more complex the history becomes. Tying these to the onshore story is
going to be quite a challenge.
Bully (Prof Martin Bates) has been working the onshore side of
this paleo-reconstruction game on the West coast of Wales for many years with a
particular focus on the forest site at Borth. Here many finds, including some impressive
antlers record very different environments back through hundreds to thousands
of years.
The new data will allow us now to better target key locations with
the palaeo-geography and to acquire higher density seismic and ground truth
data. Out there somewhere will be sites with key evidence of what the people
were doing. Just got to keep looking for
them.
