Many marine fossil concentrations are considered the result of episodi
c sedimentological events, and in particular those due to storms. Most
storm or tempestite concentrations are identified as autochthonous or
parautochthonous assemblages created by a variety of winnowing proces
ses within shallow water environments. In contrast, samples described
here from both a 'shelf' and a 'basinal' setting within the Ludlow (Up
per Silurian) succession of the Welsh Basin reveal the presence of a b
iota transported by tempestite activity into a setting dominated by a
more offshore biota. Tempestite horizons from within an 'outer shelf'
mud dominated setting include shelly lenses with a transported fauna a
bounding in gastropods, tentaculitids and atrypid brachiopods, the bac
kground sediment being rich in graptolites, cephalopods and small stro
phomenid brachiopods. Within the 'basinal' area, distal tempestites ra
nge from minor siltstone layers to thicker bioclastic limestone lenses
. The siltstones are largely graptolitic (dominated by Bohemograptus),
with some small brachiopods, whilst Saetograptus colonus is the only
common graptolite in the limestones, which also contain a fauna of bro
ken brachiopods and bryozoa. The transport of assemblages distally int
o a variety of settings represents a potential source of error in pala
eoecological analysis. Transported assemblages may, however, provide e
vidence of the composition of both benthic and pelagic shallower water
faunas no longer known in situ.