Farrant, A R. 2008.A walkers’ guide to the geology and landscape of eastern Mendip. Book and map at 1:25 000 scale. (Keyworth, Nottingham: British Geological Survey.) This guide is available to purchase from the British Geological Survey https://shop.bgs.ac.uk/Shop/Product/BSP_BEMEND
The Whatley area
Limited parking is available in Mells.
Whatley is a small village approximately three kilometres west of Frome. It sits on a ridge between the deeply incised Fordbury and Nunney valleys. The ridge is capped by Jurassic Fuller’s Earth Formation and Inferior Oolite, which overlie the older Carboniferous and Devonian rocks. These older rocks are exposed in both Whatley Bottom and the Nunney Valley.
Whatley is perhaps better known for the large quarry to the north-west of the village [16]
The quarry was opened in 1937, when stone was transported by narrow-gauge railway to Hapsford Quarry, three kilometres away for processing. In 1974, the rail link was upgraded via a new route to the Radstock–Frome line, which necessitated building two tunnels and a bridge over the Mells River.
Quarrying on Mendip
The Carboniferous Limestone is an important natural resource, and is extensively quarried in east Mendip.This is because the Mendips are the closest source of hard rock to the large markets of south- east England. Nearly all the rock produced is used for aggregate and in the making of concrete products.
Many of the active quarries were granted huge concessions in 1947 before the era of stricter planning controls. Current planning policy is to concentrate quarrying into fewer quarries outside the Mendip Hills AONB in east Mendip, where the environmental constraints are fewer and good rail links exist.
In 2002, 76 million tonnes of limestone were quarried in Great Britain, of which Somerset contributed 11.5 million tonnes, the bulk from east Mendip. Approximately 670 million tonnes of permitted stone reserves remain in the Mendips.The total economic value generated was estimated in the mid 1990s at £150 million of which £40 million went directly into the local economy.
Today, the quarry is a highly mechanised operation, concentrated in a single large pit 1.6 km long, 0.6 km wide, and about 100 m deep. The quarry currently has permission to extend west to Finger Farm and east to Murder Combe, covering about 180 hectares. Up to five million tonnes of crushed stone may be produced annually, much of which is exported by a specially constructed rail link to markets in south-east England.
The quarry is located in the belt of steeply dipping Carboniferous Limestone on the northern limb of the Beacon Hill Pericline.The quarry extends across almost all of the Carboniferous Limestone formations, with the exception of the Oxwich Head Limestone, which outcrops just north of the quarry perimeter. Within the quarry, the limestone beds dip at around 65° to 80° to the north.
A thin cover of horizontally bedded, yellow, Jurassic Inferior Oolite up to three metres thick, rests, with a marked unconformity, on the Carboniferous strata at the eastern end of the quarry. As at Tedbury Camp Quarry, 1.5 km to the north-east [15]
The base of the quarry is currently below the natural water table. As the Carboniferous Limestone is a major aquifer, water in the rock leaks into the quarry. In order to keep quarrying below the water table, the water is pumped out to maintain a water level at approximately 50 m above OD. Groundwater leakage into the quarry is stored in a pond and used to clean the aggregate; it is recycled before being discharged locally into the Whatley Brook or pumped into the River Mells to help maintain river flow [9]
Just north of Whatley village, where the road passes through a cutting [17]
Some 1.5 km to the south-west is Chantry, which lies on a narrow belt of Devonian sandstone in the core of the Beacon Hill Pericline and flanked on either side by the Avon Group mudstone. Small, southerly dipping outcrops can be seen along the banks of the lanes south of Chantry Pond. North of the pericline, a small stream flows off the sandstone and sinks underground into the Avon Group at Chantry Slocker [18]
Near Chantry village are two of the six iron works operated by the Fussell family. James Fussell V, the grandson of the James Fussell III and the founder of the Mells iron works, lived in ‘The Chantry’. This large villa, built in 1825, is set in landscaped grounds just south of Chantry Church. Chantry Pond was a feature of these grounds, but also served as the mill pond for the Chantry Iron Works [19]