Directly beneath Glossop lie areas of Carboniferous Millstone Grit, shales and sandstone. Glossop is on the edge of the Peak District Dome, at the southern edge of the Pennine anticline. The Variscan uplift has caused much faulting and Glossopdale was the product of glacial action in the last glaciation period that exploited the weakened rocks. The steep-sided valleys of the cloughs cause significant erosion and deposition. The layers of sandstone, mudstones and shale in the bedrock act as an aquifer to feed the springs. The valley bottoms have a thin deposit of boulder clay. The brooks are fed by the peaty soils of the moors thus are acid (pH5.5–7.0); this means the instream wildlife is dependent on food sources from outside the channel.
