Here an outlier of about 800 feet of Westphalian strata, two miles long from north to south, and up to half a mile wide, is bounded on the north-east by the Pennine fault system and the south-east by the Dent Fault system. There are, at least, twelve coals, none of them with a known name, but the highest of them has been correlated with Cumberland’s Main seam and Bensham in Durham. The lowest correlates with the Ganister Clay, near the base of the Durham coalfield. The dislocation of the strata has been so great that the seams are almost vertical. Productive measures outcrop only in Argill Beck, where coal has been mined from adits driven into the banks south of Gillbank House. One seam was three feet thick, and the highest in the series had 57 inches of poor quality coal. Mining was probably active in the late seventeenth century, but had finished by the mid-nineteenth.
Coal pits at Broxty and Borrowdale, respectively short distances to the south and north Argill Beck, worked the Little Limestone seam in strata of the Pendleian sub-stage of the Namurian.
- Ford, T.D. “The Upper Carboniferous Rocks of the Stainmore Coalfield” Geological Magazine, Vol.92 (1955), pp.218-230