Sub-Aqua Adventure: Low Spring Tides at Seymour


One aspect of our research on Jersey is looking at how humans used the landscapes now submerged under the English Channel. Around Jersey much of this landscape is dominated by a hard granite geology full of gullies and widened joints which trap useful sediments but which isn’t masked by recent sand. This means these landscapes haven’t really changed substantially in the past few hundred thousands years, unlike the soft, chalky Cretaceous landscapes of the eastern part of the English Channel/La Manche Region which have changed considerably, and have potential for archaeology to be preserved.

In addition to this Jersey and the wider Gulf of St Malo have an incredible tidal range, one of the highest in the world, where the change in sea level between high and low tide can be as much as 12 m.


So when we were offered a tour of the exposed granite reef on Jersey’s south eastern coast by Dominic Jones we jumped at the chance.  Dominic has learned to understand this landscape through years of experience since childhood. It is a very dangerous landscape where it is easy to walk out almost 2 miles across exposed sea bed at the lowest tides, but easily get cut by rising water when the tide changes. In Dominic’s safe hands we were shown an incredible world,one which we have been wanting to explore since we first came to Jersey.


It’s real magic lay in being able to walk across several square miles of a landscape which was once where Ice Age animals, Neanderthal and modern human hunters moved to and from the island. The alien, rock landscape was one in which visibility changed all the time, a landscape of cut-off gullies and wide, shallow streams. A perfect location to track, ambush and kill prey.


We spent a few hours surveying this landscape for potential sediment traps, finding areas where Ice Age sediments remain perfectly preserved below a few centimeters of sand. Each location was logged by GPS, the points on our handhelds showing only blue sea.


But we know more than the digital maps tell us, as here, in the Channel Islands, you don’t need scuba gear or an ROV to touch and explore the submerged Ice Age landscape. You just need some planning, thought, a tide table and a guide.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: