BRITISH CHALK PLANTS
A variety of scrappy fossil plant remains are encountered in the British Chalk. These were sourced from nearby land, so are most abundant in the Grey Chalk, deposited when sea-levels were lower and hence more land was exposed. Land areas in the Late Cretaceous of NW Europe correspond roughly to the mountainous regions of today; the Pennines, Northumberland, and the Caledonian Highlands of Wales, Scotland and Scandinavia. Southern Britain was positioned approximately 35°N of the equator (around 15° / 2,000km south of its current position, equivalent to N Africa today) and the global climate was under greenhouse conditions, so the flora was more tropical than today.
The plant record in the Chalk is dominated by associations of plant fragments, often with a tubular form. These are evidently fragmented fronds, but the process which caused them to form tubular associations on the sea-floor is unclear. Possibly they represent dinosaur coprolites (dung) that have dried and floated out to sea, or perhaps a burrowing creature on the sea-floor drew in the plant remains to line its burrow, analogous to the fish-scale lined worm-burrows Terebella lewesiensis.