Framework-forming cold-water corals (CWC's) such as Lophelia pertusa and Madrepora oculata generate positive
topographic features on the seabed called CWC mounds. In the North East Atlantic, CWC mounds have been
studied in detail and reveal heterogeneous spatial on-mound organisation of coral patches. Many of these studies
are limited by a paucity of remotely-sensed and video imagery at an appropriate resolution and coverage. This
study is the first attempt to video mosaic an entire CWC mound (the Piddington Mound of the Moira Mounds,
Porcupine Seabight, Irish margin). The mosaic is divided into 18,980 0.25 m2 cells with a manual classification
applied to each within a geographic information system (GIS). Geospatial analysis shows that cell distribution is
not random but clustered significantly across the mound surface. These clusters of cells make up a ring-like facies
pattern. A model for the processes that lead to this facies pattern is suggested based on contemporary environmental
controls. Parallels to shallow-water reef atolls are also drawn which subsequently has implications
for interpreting fossil coral outcrops.