- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
"Underground borings through the lower and Middle Coal Measures beneath the Firth of Forth have proved sequences of rhythmically bedded volcanic detritus and a thin basalt lava. The detritus is believed to have been derived from a contemporaneous cinder cone or cones previously located by an off-shore boring. The new evidence suggests that locally there was an eastward shift of focus of eruption during Coal Measure times. The relationship of volcanism to this type of rhythmic sedimentation is discussed."