At the time of deposition, Britain was just south of the
equator (<5° S) and part of the
Euramerica continent. Study of the growth rings of fossil wood from other localities indicate that the British Isles had a
monsoonal climate during the
early Carboniferous, with tropical rainfall seasonality. The Eyam Limestone was deposited on an extensive, thick carbonate ramp and platform on the northeast margin of the
Widmerpool Gulf (an extensive basin which existed as an area of open water during the time of deposition).
Reefs and their associated fore-reef and
lagoonal environments are represented in the Eyam Limestone, with
crinoids dominating the reef and providing habitats for other animals. The presence of
photosymbiotic coral and micritic envelopes on some crinoid ossicles indicates the formation was deposited within the
photic zone in a
marine environment of normal salinity. The presence of the
xenacanth Bransonella has been suggested to imply freshwater influence as xenacanths live mainly in freshwater habitats, however its presence in other marine formations suggests that
Bransonella was a marine animal unlike its relatives.
Apatite crystals formed by the recrystallization of
phosphatic overgrowths are present on some
conodont elements from the formation. As phosphatogenesis only occurs in the anoxic-oxic boundary while apatite
precipitation occurs in the top few centimeters of the sediment column, this reveals that shallow sediment with low geothermal temperatures and dysoxic conditions were present in the Eyam Limestone. ==Fossil content==