Geology, mining and landscape

Places and setting

Marske is located in Swaledale, the most northerly of the Yorkshire Dales, on the east side of the Pennines. The village of Marske is located near the confluence of Marske Beck and the River Swale, and is around 8 km west of Richmond.  Marske Beck rises along the watershed north of the Swale, between the Swale and the Greta (a tributary of the Tees).  The area of high moorland at the head of the beck, and on the watershed, is “New Forest“.

Historically Marske Parish was made up of four principal manors: Marske (on Marske Beck), Clints (to the east of Marske Beck), Skelton (to the west of Marske Beck) and Feldom (at the head of Clapgate Gill and north of Marske village). The Parish now also includes the area of New Forest. The photos below compare the scenery today with that of the early twentieth century.

Marske Geology

The Pennines were formed by a mountain building episode which created the north-south orientation to the backbone of England from Derbyshire to Northumberland.  The north Pennines are structurally divided into blocks by major faults that run east-west. North of Marske faults such as the Lunedale fault, and the Stainmore Trough (the trough is a syncline – a downwards u-shaped flexing in the earth’s rocks), divide the Askrigg Block, on which Marske, Swaledale and Wensleydale all sit, from the more northerly Alston Block¹.

Both the Askrigg Block, and the Alston Block are underlain by granites which were emplaced as molten rocks into the earth’s crust. The Wensleydale granite, which lies under the Askrigg Block (on which Marske sits), dates from around 400 million years ago². A borehole drilled near Semerwater in Wensleydale in the 1973³ found the granite to be only 500m below the surface¹. The granites are less dense than the surrounding rocks, and they have tended to lift the surrounding rocks, and hence have been responsible for the high elevation of much of the Northern Pennines.

The surface geology in the Pennines around Marske is dominated by rocks from the Carboniferous period, laid down near the equator between 360 and 300 million years ago.  (This will take you to the British Geological Survey “geology viewer”.) The valley of Marske Beck sits on strata made up of rocks dominated by bands of limestone and chert, intercalated with some sandstone and shale, dating from 337 to 328 million years ago^1,5.  The striking cliffs of Clints Scar, which make up the eastern edge of Marske Beck, are made up of the “Main Limestone”⁶. Above the Main Limestone lies the Richmond Chert. A small outcrop of more porous sandstone can be seen on the bridleway just south of Orgate Farm.

After the carboniferous limestone rocks had formed faults developed in them across the north of England. In the Richmond/Marske area the longer faults are predominantly on a west/east bearing (varying from WSW-ENE to WNW-ESE), although many smaller faults also have a more north/south bearing⁷. It is these faults that often became the sites for the lead-bearing veins that are described below.

The most prominent fault in the area is the “Marske Fault”, whose presence can be deduced by the level of the cliffs north of Downholme Bridge (see photo). The “throw” of this fault is around 30m⁸. A smaller local fault is the Orgate fault, which similarly has an impact on the appearance of the line of cliffs, along and north of, Clints Scar. Faults which make up today’s fabric of the Pennine rocks reflect earlier weaknesses in the older, and largely invisible, deep “basement” rocks, in the same way as cracks in plaster can reflect the underlying brickwork. These pre-existing structures shaped the later action of stresses in the overlying limestone. In the carboniferous era these stresses first of all led to north-south stretching of the earth’s crust which created rift-valley like basins¹. These earth movements had ended before the Permian era – and created the setting for the lead mineralisation.

The North Pennine Orefield and Marske

The mineralisation of the carboniferous rocks in both the Askrigg Block (within which Swaledale and Marske lie), and the more northerly Alston Block (including Weardale), makes up the “North Pennine Orefield”. A huge body of academic literature covers the Orefield, and even the most inconspicuous veins of minerals have had whole chapters devoted to them.

A source of heating in the earth shortly after the Carboniferous era led to the mobilisation of mineral rich ground-water in the rocks. Within the hard and impermeable limestones of Swaledale the mineral rich waters tended to form both well-defined vertical veins, and also “flats” of horizontally lying ore. Veins could be anything from a few centimetres thick to over a metre. They commonly included the valuable the lead ore galena (PbS), and sometimes traces of zinc and copper ores. However the bulk of the veins were dominated by less valuable minerals such as calcite, flourspar, barytes and witherite (barium sulphate and carbonate respectively). These so-called “gangue” minerals can often be found in waste tips near old workings^3,9.

Most of what follows here is about lead mining. However some copper ore was found on Feldom Moor³ to the east of Marske, and the bridge on the road to Ravensworth is called Copper Mill Bridge for this reason.

The vertical extent of the mineralised zone is not very great, the majority of the veins being in the Main Limestone and Chert Beds above it³. In the Marske area in these beds is not as extensive as in areas in Swaledale to the west (e.g. around Gunnerside), nevertheless the lead ores here were mined over hundreds of years³.  

Lead Mining and Smelting around Marske

Lead mining and smelting in the area has a very long history. Raistrick, who wrote prolifically about mining in Swaledale from 1927 until at least 1975², noted that in the nineteenth century a “pig” of smelted lead was found in the Hurst area, just north of Marske Beck, with Emperor Hadrian’s name inscribed on it (he reigned from 117 to 138AD). Alas that evidence has now been lost. Perhaps it was melted down at some point to make a roof or a gutter³. By the twelfth century lead was being used in prominent buildings nationwide for pipes, cisterns and roofing – including at Windsor Castle and Waltham Abbey. Raistrick suggests much of this lead may have come from Swaledale via traders in Richmond and York³.

Mining

Early methods of mining the lead ores included “bell pits”. These were small pits up to six metres deep dug vertically from the surface into an exposed vein. Poor ventilation and drainage often led to the pits being abandonned at a certain point – until the whole process was repeated further along the same vein – leading to a lines of pit workings pock-marking the hills. As mining developed “levels”, or “adits”, were dug vertically towards known veins to assist drainage³. An example of a level near Orgate is pictured below.

By the eighteenth century new technology in the form of steam power for pumping and waterwheels for winding engines began to appear to assist mining elsewhere in Swaledale. However around Marske the veins were not as remunerative – and there is no evidence of such heavy machinery as there is to the west in Gunnerside.

The nineteenth century saw the continuation of more traditional mining at Skelton, near Telfit, and in Marske “manor” (north of the Marrick Smelt Mills)⁶. The censuses however note only a very small numbers of miners living at Clints, Skelton and Hazelhaw (high on the Marske/Reeth road) until the 1870s. In contrast the numbers of miners at nearby Hurst to the west of Marske overwhelmed all other occupations there (see population). The story of a family from north of Marske, and near to Hurst, who emigrated to America is told in the pages on New Forest. More generally emigration from Swaledale to the Upper Mississippi Valley, driven by the prospect of lead and farming opportunities, was not unusual in the mid-nineteenth century (see also page on New Forest).

Smelting

A detailed description of the science around smelting is included here. The earliest methods for then extracting lead metal from the galena ores (lead sulphide) included creating fires of brushwood to smelt the lead ore (smelting oxidises the suphur from the galena leaving pure lead). Crudely crushed and washed ore (to remove lighter gangue minerals and stone) was mixed in with the wood and heated to form lead metal³. These hearths were called “bail hills”, and are often found on the edges of hills in Swaledale where the prevailing wind was strongest.

By the sixteenth century what we would today recognise as a furnace, with a chimney and some form of heating beneath a grate, were used to smelt the lead ores³. This in part was based on new technology imported from Derbyshire and [Germany]. According to Raistrick’s book on the lead industry in Swaledale³ the “earliest smelt mill we know in Yorkshire was the one at Clints, near Marske”³. The 1759 map¹⁰ of the Clints Estate (see illustration) includes the annotation “Here lead from Arkengarthdale is smelted.”

Whilst mining itself was not as profitable in the Marske area as around areas to the west such as Gunnerside or Grinton what the Marske area did offer was a very good site for smelting mills. Marske was favoured by plentiful supplies of water for dressing ores, and wood for charging furnaces. When coupled with restrictive land ownership in parts of Arkengarthdale this led to some miners haulin ore by packhorse from there to smelt mills in the Marske Beck between Clints and Telfit⁶ The attractive packhorse bridge just east of Telfit is prominent evidence of this. Lead workings, and buildings for dressing ores, and found west of Helwith (see below).

Whilst the impacts of lead mining in the Marske area have been less damaging than workings at Hurst or Arkengarthdale to the west it remains that case to this day that there are some areas of land where it remains unsuitable to graze lambs¹¹.

How Glaciation affected the Marske area

Following the deposition of the Carboniferous rocks in the Pennines scientific work suggests that the limestones and cherts seen around Marske were buried by around 1.5km of overlying deposits during the 300 million years that followed¹.  Sometime between then and now any newer deposits have been eroded away, and now presumably sit in the Vale of York or at the bottom of the North Sea!  The most recent period of erosion coincided with the last glaciation, which reached its peak around 18000 years ago. For the record this period is known as the Dimlington stadial of the Devensian glaciation.  At this time the climate was dry and arctic-like – mammoths, bison and woolly rhinos roamed Yorkshire¹, although no such animal remains have yet been found in this area! Ice covered the whole of Swaledale, including the surrounding hills. Notwithstanding this the story of how glaciation affected Marske and Swaledale is set out separately here. It tells a story that encompasses the landscape of the Richmond “gorge”, steep-sided Marske Beck, the 10km feature that is Feldom Rigg, and the vast area of landslips below Clints scar.

This nineteenth century painting of Swaledale from Marske Edge, and showing the gorge towards Richmond Castle, is of a landscape shaped by ice.

1. BGS (British Geological Survey). Fourth Edition, 2002.  The Pennines and adjacent areas.  Part of British Regional Geology series – very descriptive with some explanatory material.[↩][↩][↩][↩][↩][↩]
2. BGS (British Geological Survey). 1985.  Geology of the Northern Pennine Orefield: Volume 2:  Stainmore to Craven.  Highly detailed memoir.[↩][↩]
3. Raistrick, Arthur. 1975 (1991). The Lead Industry of Wensleydale and Swaledale. Vol 1. The Mines.[↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩]
4. British Geological Survey.  Fifth Edition, 2010.  Northern England.[↩]
5. BGS (British Geological Survey). Fifth Edition, 2010.  Northern England.  Part of British Regional Geology series – very descriptive with some explanatory material.[↩]
6. Northern Mines Reseach Society. (Author: Tyson, L.O.) 1994. Mining and Smelting in the Marske Area, Swaledale. British Mining Memoirs, Number 50.[↩][↩][↩]
7. BGS (British Geological Survey). 1997. Richmond. England and Wales Sheet 41 (1:50000 map).[↩]
8. BGS (British Geological Survey). 1878. County series 1:10560 map – Yorkshire Sheet 38. Available at BGS maps portal – accessed 2023.[↩]
9. www.geologynorth.uk.  Accessed 2022. Useful and well explained website on some features of geology of north – mainly Pennines and Northumberland.  Good descriptive section of Northern Pennine Orefields.[↩]
10. Richardson, R. 1759. A Plan of the Clints Estate. Coloured estate plan in North Yorkshire County Archives, Ref ZAZ(M)3.[↩][↩]
11. Local contributor 3:  Notes on Marske village and local farming.  2023.[↩]