Ice Age Island – the Saga Continues
So we have
returned for another season in Jersey as part of a three year project to explore the deep prehistoric past, from
exploration of the island caves, through the archaeological excavation of
hunter gather camps preserved in the island’s interior, to the iconic sites at
La Cotte de St Brelade. In all of these
locations we aim to discover why this remarkable landmass attracted Neanderthal
and modern humans at different time periods. Over the past 3 years we
have been acquiring geophysical data both onshore and offshore in order to
re-create the landscapes of the past. We
have also had a number of investigation sites such as the one at Les Varines
shown below.
Les Varines dig 2015 |
Earlier
in the spring we acquired 2D electrical resistivity tomography (ERT) data at
the site, which together with boreholes drilled through the sequences allowed
for the targeted expansion in the excavation.
At the
other side of the island we are trying to survey cliff sections that will give
us further insight to the history of climate change in Jersey over the last
200,000 years as recorded in the sediment sequences, and hence palaeogeography
of the La Cotte site. In Portelet Bay to
the south east of St Brelades there is a particularly well exposed Pleistocene deposits. The only problem is that its 15m high and
loose – a job for extreme geophysics! By
abseiling off the top of the cliff we were able to clean a sufficient amount to
achieve mapping, photography, sampling (for OSL dating, palaeo-climate and
palaeogeographic setting) and a geophysical profile. The geophysics consisted of both magnetic
susceptibility and DC resistivity. The
mag did not produce much differentiation however the DC resistivity mapped
distinct boundary changes within the various units. The preliminary results are
shown below and you can visit here for some live action!
Some preliminary results
See some of the previous work for the
site at an older blog:
For more information also see:
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