Plant ID please

[chunkychambers]

This plant is spreading all over the rocky shoreline of the estuary down here, in some places its so thick it's like walking on a purple blanket.

Sorry about the shot, but it's definately purple with green "under-shoots". I don't know how it manages to survive on a rocky/ shale shore line, there can't be much sustinance for it, maybe thats the reason for its long roots.

Can someone put a name to it please

[Tiggrx]

Bit hard to tell from the picture - but could be Sea-blite (Suaeda maritima)

[Paul mabbott]

These couldn't be glassworts, could they? Marsh samphire as it's known in some places - Samphire - Salicornia europaea agg -
In France they turn red towards the end of summer. Maybe not!