West, Ian M. 2014. Burning Beach, Burning Cliffs and the Lyme Volcano: Oil-Shale Fires of Southern England; Geology of the Wessex Coast. Internet site: www.southampton.ac.uk/~imw/kimfire.htm. Version: 6th June 2014.
Burning Cliffs of Dorset - Oil-Shale Fires

Ian West, Romsey, Hampshire

and Visiting Scientist at:
Faculty of Natural and Environmental Sciences,
southampton University

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Burning blocks of Kimmeridge oil shale or blackstone, a potential source of shale gas by fracking, seen in a small artificially started fire at Kimmeridge, Dorset, 2013

Kimmeridge oil shale or Blackstone burning east of Cuddle, Kimmeridge, Dorset in July 2000

Oil-shale fire east of Cuddle, Kimmeridge, Dorset Oil-shale burning on beach, east of Kimmeridge, Dorset Oil-shale fire, Kimmeridge, close-up

More on Kimmeridge Oil Shale! - Go to:
Kimmeridge - The Blackstone or Oil Shale (at Clavell's Hard and Elsewhere)

Other Kimmeridge Field Guides

Kimmeridge, - Introduction
Kimmeridge - Fossils
Kimmeridge - Kimmeridge Bay
Kimmeridge - East - Hen Cliff, Yellow Ledge and Cuddle
Kimmeridge Bay - West to Gad Cliff
Kimmeridge - Blackstone, Oil Shale at Clavell's Hard
Kimmeridge - Rope Lake Head to Freshwater Steps
Kimmeridge - Freshwater Steps to Chapmans Poole
Kimmeridge - Bibliography - Start
Kimmeridge - Bibliography Continued

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Associated webpage:


(You can download this educational site to SurfOffline, WebCopier or similar software to keep a safe permanent offline copy, but note that at present there is periodic updating of the live version.)

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Safety; the Hazards of Kimmeridge Cliffs

Note that there is some significant danger with regard to the Kimmeridge cliffs. One danger, the main one, is risk of rock fall; the second hazard is that of being cut off by the tide. This applies particularly to the cliffs east of Kimmeridge, although it could also happen at Brandy Bay and elsewhere. In general, keep out as far from the cliffs as possible. Some debris falls every day and if you are close to the cliff you are at risk of being hit by a rock-fall.

Cliff collapse at the old No. 2 Level of 1890 Blackstone workings, just west of Clavell's Hard, Kimmeridge, Dorset

Because of the hazard of rock falls and it is a dangerous place to visit unless it is well-understood and proper precautions are undertaken. The cliffs are vertical and high and subject to erosion by the sea at the base. The shale and mudstone is full of joints and fissures and not stable. Small pieces will tumble off from time to time as you walk along.

More serious are substantial falls like the one shown above. These may occur without warning; suddenly there will be a loud crash and a plume of debris and dust. These happen particularly in certain weather conditions, such as when there is frost or rain and sometimes when the shale has dried in the hot sun. If you are out on the low-tide ledges falling debris would not usually reach you but there is no guarantee of safety. The risk is greatest where the cliffs are highest, where there is joint-separated shale above and where there is evidence of a recent fall in the form of shattered debris.

With regard to this particular webpage on Kimmeridge Clay oil shale fires, it is quite obvious that any fire in progress is hazardous. Apart from the danger of catching fire it should be noted that splinters of hot shale can burst out of oil shale fires. The fumes are nauseous, very objectionable, and should not be breathed. The ash could be harmful. Thus oil shale fires should not be approached closely and one should not remain downwind of such a fire.


Kimmeridge Safety Addendum:

Photographs shown on this website have been taken over a period of many years by the author and various other people. Some photographs are from organised field-trips, which may be those of the present author or of other geologists. Many, though are from informal, private coastal walks, or from private, research field-trips. The photographs are for geological purposes only and are there to show rocks, not people or techniques. They are not intended to show safety procedures and no activities shown are necessarily intended to be copied. This website is about geology for geologists. The cliff, sea, tide and weather conditions vary greatly so always make your own assessment of the cliffs and conditions on the day, and arrange your coastal procedures in accordance. Always consult tide tables before field work at or near Kimmeridge. No responsibility at all is taken for any activities of field parties or individuals going to the Kimmeridge coast for their own purposes or objectives. As at other geological sites a risk is present and the possibility of an accident, although a rare occurrence, cannot be eliminated.


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Burning blocks of Kimmeridge oil shale, ignited artificially, showing the gasy type of burning

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Burning Beach, Cuddle, Kimmeridge, July 2000

View from Yellow Ledge

A fire in fallen oil-shale was discovered east of Kimmeridge by David Meadows on the 31st July, 2000. It was still burning vigorously on the 18th August, 2000, although the main area of oil-shale debris seemed to be almost consumed. On the 17th September, 2000 there was no obvious fire visible but noxious fumes were still coming from the burnt area. It is now completely extinguished. Details of this fire and discussion of previous oil-shale fires on the coast of Dorset are given here. The beach fire was in fallen debris from the Blackstone, lying on the beach between Cuddle and Clavell's Hard. The cliff itself is not burning significantly, although a thinner oil-shale above the Grey Ledge Stone Band was in contact with a burning heap of finer debris. A fumerole was present and sulphur has been precipitated and oil has been naturally distilled. It is not known whether the fire has started naturally by oxidation of pyrite or whether oil-shale debris has been intentionally ignited.

Access to the fire is not easy and depends on favourable tide conditions. Because debris frequently falls from the cliffs here, there is risk of serious head injury unless safety helmets are worn and every effort is made to keep clear of the foot of the cliffs. At low tide there is access along the slippery shale ledges and foot of the beach. At higher tides the conditions are hazardous and efforts to approach the fire are not recommended. It can be seen, however, from vantage points on the cliff top. Please see the safety notes provided for the Dorset cliffs.

Kimmeridge oil shale or Blackstone burning east of Cuddle, Kimmeridge, Dorset in July 2000 Oil-shale burning on beach

The photographs above show burning oil shale, eastward from the Yellow Ledge dolomite stone band at Cuddle, east of Kimmeridge. In one of the pictures Clavell's Hard, where there has been an oil shale fire in the past, can be seen. David Meadows, present in the photographs first reported this oil-shale fire fire. In one of the photograph note that the heating and expansion of oil-shale causes some small explosions, throwing pieces of oil-shale into the air. The fire is slowly moving in a westward direction, away from the camera. The fumes given off by these fire are very sulphurous and unpleasant and probably resemble those that would be created by burning a mixture of paraffin and bad eggs. They can be detected at least a kilometre away.Sulphur (see below) is precipitated from a small fumerole.

The initial report of the fire was this email sent by David Meadows on the 1st August, 2000l:
You may be interested to know that I was walking the coastal path about one mile east of Kimmeridge on the 31/7/00, when I saw a lot of smoke rising from the beach. The smoke smelt of burning tar and from the point to the east of it I could see that a large patch of beach at the base of the cliff was burning. Flames were visible and a large area was blackened, the extent of which was difficult to estimate from where I was. I assume that oil shale had ignited spontaneously.

Following this, Mr and Mrs Meadows and myself went to the cliffs on the 18th August when there was a suitably low tide. The area is only accessible at low tide and it is not a recommended place to visit because there is danger of falling debris from the cliffs. This happens quite frequently. The best time to go is a very low tide because then there is safe access round the headland at Cuddle, and it is possible to walk on the ledges near low-water mark, which is relatively safer. The photographs shown here were taken on that day, during which, unfortunately, it was raining.

Ian West at the Grey Ledge fire

The fire, seen here on the 18th August with Ian West and a metre rule for scale, is only easily studied from upwind (the photograph was taken when there was a light wind from the southeast). The dense smoke has a very sulphurous and oily smell, as noted when it was used in the 18th century for local industry. Coker (1732) recorded " in burning it yields such an offensive savoure and extraordinary blacknesse, that the people labouring about these fires are more like furies then men". The sulphurous fumes of this relatively small fire can be detected at quite a distance, it seems as far as the car park at Kimmeridge, if the wind is blowing in the appropriate direction.

beach fire, close

Here is a close view of the fire with flames and heavy obnoxious gas and smoke coming off. Notice the worn beach pebbles of shale that are in the fire. Presumably wave action has thrown large pebbles on top of the oil-shale.

The dimensions of the area of the fire are 24 metres east-west along the cliff by 3m from the cliff edge in a seaward direction (area of 72 square metres). On the 18th August the fire was burning at the western end of a fallen strip of oil-shale, or Blackstone with a small fumerole under a pile of debris at the eastern end. Most of the stretch of 24m seems top have been on fire in the past and to have largely burnt out. The fire probably extended down for little more than half a metre to a metre at most. Flames, as can be seen come directly from blocks of Blackstone of about 20cm or so in length. Underneath the blocks the rocks are glowing red hot. Some flames are above the surface level and clearly come from gas distilled from the oil-shale. As can be seen in one of the photograph above, small explosions take place from time to time as blocks of shale burst in the heat.

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Burning Beach, Cuddle - Relation to the Cliff

Cliff sequence at Grey Ledge

Top: Part of the cliff sequence in the Kimmeridge Clay between Cuddle and Clavell's Hard. This is just west of the beach fire and starts with the Grey Ledge Dolomite Band. This stone band is an argillaceous dolomite and was once quarried at Cuddle promontory (Blake, 1875; Arkell, 1947). It was worked in adits in the cliff. An old map redrawn in Legg (1984) shows, just east of the Cuddle promontory "rail tracks emerging from the lower of two bands of calcareous marl apparently extracted for cement making". This would tie in with the Cattle Ledge Dolomite Band, which is lower. Perhaps both these similar bands were worked. The stone was sent to Newport, Isle of Wight for cement manufacture. Higher in the cliff are some thin oil shales in a calcareous shale sequence. The Blackstone, the main oil shale, is conspicous as a projecting, rather angularly jointed unit. It appears either black when the actual oil shale is visible, or white when calcite coating joints is seen. Higher in the cliff is the hard Rope Lake Head Dolomite Band. Apart from dolomite this contains coccoliths when studied under scanning electron microscopy and is notable in the field for containing large horizontal U-shaped burrows of Thalassinoides, a trace fossil. There is much fallen debris from this hard bed in the bay.

Sequence at fire

The beach fire is where a projecting ledge of Blackstone, the oil shale in the middle of the cliff has fallen. The oil-shale, including its partings, is about 0.9m in thickness (2ft 10 inches or 0.86m according to Arkell, 1947), east of Kimmeridge Bay.

Boudinage in oil shale

Two other thinner oil-shales near the foot of the cliff in the area of the beach fire. These show the peculiar feature of boudinage. This is presumably the result of overburden because the area has not been heavily tectonised. At the time of photography these shales had not caught fire and are probably unlikely to do so because they are not heavily fissured, which would favour oxygen supply and thus burning. The brown markings result from the oxidation of pyrite nodules. Pyrite nodules are common in association with oil-shales because they have been formed from accumulated organic matter on the sea floor and this results in very reducing conditions in the sediment and the flourishing of sulphate-reducing bacteria (they produce hydrogen sulphide which then reacts with any available iron to form pyrite).

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Burning Beach, Cuddle - Fumes, Fumerole, Sublimates etc.

The fire has heated the shale to red-hot condition as can be seen in some of the photographs. The shale becomes baked red as the reduced iron, present as pyrite, is oxidised to hematite. Much oil is deposited at the margins of the burnt material, and sulphur occurs in fumeroles. Some examples are now shown:

Fumerole in fallen debris The mound of fallen debris, mostly shale fragments of small size, acts as a fumerole. A small amount of smoke coming from the top is not clearly seen in the photograph. Against the upper part sulphur is precipitated and there is oil distilled from the kerogenous shale debris beneath. The pile is of both oil-shale and less bituminous shale.

Sulphur at fumerole

Sulphur precipitated at the top of this fumerole. It has been deposited on red-burnt pieces of shale. The curved objects are pieces of seaward blown or washed on top. Much sticky, tarry, oil has been deposited on the vertical surface of the cliff to the right.

Dead sand-hoppers

This photograph was taken closer to the main mass of burning debris on the beach. Sandhoppers (Beach Fleas) have been killed by fumes and heat. These beach crustaceans are very abundant on the Kimmeridge beaches with their masses of decaying seaweed.

Burnt shale

Shale is commonly burnt to the conditions of rather flaky, red tiles in the oil-shale fires. The shale was not seen in very vitreous condition or completely fused. Much sticky, tarry, oil has been deposited on the red-burnt shale.

Partially burnt shale

Here there is seen a gradation from red-burnt shale at the base to less altered shale above. Some oil has been deposited at the margins of this block of shale.

As mentioned above the fumes from the fires are both strongly sulphureous and strongly oily. X-ray diffraction studies of the residue of the fire show much anhydrite to be present. This anhydrous calcium sulphate is common as an evaporite mineral in arid environments and in boreholes and also present in 'black smokers' on mid-oceanic ridges. It does not normally occur on the Dorset coast because the damp climate hydrates any anhydrite to gypsum (calcium sulphate with water of crystallisation). Anhydrite has been reported by Cole (1975) in the debris of the Clavell's Hard Burning Cliff, referred to below. It seems probable that sulphurous fumes with sulphur dioxide from burning of pyritic oilshale have reacted with hot calcite (calcium carbonate) or hot burnt calcite (quicklime - calcium oxide) in calcareous shales to form the anydrite. The anhydrite in the samples will be investigated further.

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Clavell's Hard Fire - 1973-1974

(See in conjunction with this the Kimmeridge Oil Shale webpage.)

Newspaper report of oil shale fire at Clavell's Hard, Kimmeridge, Dorset, November 1974

Clavell's Hard mining ledge, east of Kimmeridge, Dorset, seen from the cliff edge to the NE, 18th July 2008

The Kimmeridge oil shale fire in the cliff above the Clavell's Hard mining ledge, east of Kimmeridge, Dorset, in 1973

Doug Cole visits site of oil shale fire, Clavell's Hard, Kimmeridge, Dorset in 1974

The site of the old oil shale fire at Clavell's Hard, Kimmeridge, Dorset, as seen in August 2000

The mining ledge at Clavell's Hard, east of Kimmeridge Bay, Dorset, as seen on 4 October 2005, with Halfdan

The mining ledge seen from the beach directly to the south is shown in the images above. The oil shale is at the level of the ledge, just above the top of the black shale in the sea-cliff.

About 1.6km east of Kimmeridge Bay is the small headland once known as Blackstone Point but usually referred to as Clavell's Hard (map ref. SY920777). The Kimmeridge oil-shale or Blackstone was worked here and just to the east it descends to the beach. Signs of the old workings are obvious from the cliff path above or from the beach. There is a mining ledge from which two adits entered the cliff. One of these, no. 4 is still open whereas no. 3 (the western) has collapsed. On the cliff top around here there are some old tramway lines remaining, and other workings can be seen east and west of the mining ledge. The name 'Clavell's Hard' referring to a hard or landing place of Sir William Clavell, the owner of Kimmeridge around about 1600, and an early exploiter of oil-shale. At Clavell's Hard the oil shale was probably worked on various occasions from the the 17th Century to the 19th Century. The Blackstone was used as either a fuel or a source of oil. The main workings on the ledge were from the 19th Century and there was some sort of pier extending seaward from this from which shale could be loaded onto boats.

Mansell (1967), and quoted in Legg (1984), summarised the history of the mining ledge:
"The most obvious remains of the ninteenth century enterprises are to be seen in the cliff at Clavell's Hard, a mile to the southeast of the bay. Here were tunnels running into the cliff about thirty feet [10m] above the shore level. One such tunnel [No. 4 level] still remains, though its mouth is gradually being closed by falling shale. They were connected by a ledge, presumably artificial, which still remains, though in an unsafe and dilapidated condition. Along the ledge once ran a railway from tunnel to tunnel. Below the ledge, at low tide, one can find circular cuttings in the flat rocks, usually covered with seaweed or full of stones. In these are the metal bases of the uprights of which the purpose was presumably to carry some sort of pier."

Maxwell (1927) also mentioned the tramway that once carried trucks from the tunnels to the quay or pier. For more information see Legg (1984).

Clavell's Hard from the east

Deserted coast - Clavell's Hard or Blackstone Point seen from the beach to the east, at low tide on a wet day (18 August, 2000). The flat boulders on the beach are fallen blocks from the Rope Lake Head dolomite band which descends with a gentle dip to the east at Rope Lake Head, a short distance east. Note that you can get cut off here by a rising tide and forced back to the cliffs from which debris regularly falls! The ascent to Clavell's Hard mining ledge is slippery and dangerous and there is no safe route to the top.

Clavell's Hard, 2000

A closer view of the mining ledge at Clavell's Hard from the southwest (18 August, 2000). You can see the red shale above the ledge.

Site of Burning Cliff, Clavell's Hard

Here is a closer view of the burnt shale. This was taken in the 1980s when the ledge was more accessible. The wild cabages, so common on these cliffs, are growing over the shale.

The eastern part of the Clavell's Hard mining ledge, with evidence of the cliff fire, east of Kimmeridge Bay, Dorset, 17th October 2008

Examining the burnt shale, towards the top of the Clavell's Hard Mining Ledge, east of Kimmeridge, Dorset, October 2008

Even in October 2008 some of the burnt bituminous shale can be seen near the top of the mining ledge. The lamination is preserved and ammonite impressions can still be seen in the burnt shale.

Site of the 1973-4 oil shale fire at the mining ledge of Clavell's Hard, east of  Kimmeridge Bay, Dorset

This, then, is the site of the 1973 oil-shale fire at the back of the Clavell's Hard mining ledge. At the present time the central fire area still shows as a conspicuously reddened cliff, with some additional reddening near the mining adit a short distance to the east on the ledge.

The fire was noticed on the 22 October, 1973 by walkers on the cliff-top path. They smelt burning and were surprised to see smoke coming from cracks along the cliff edge for about 2 metres (6 feet). Five weeks later someone descended to the mining ledge and saw smoke issuing from vertical cracks. I saw it smoking for a long period of time, with fumeroles depositing sulphur and oil residues. It caused reddening of the shale and precipitation of sulphates. The image shown on the left here is from the 1970s, not long after the fire went out. Initially, the fire was in the back cliff of the mining ledge just west of the remaining open adit (No. 4 level). At that date the mining ledge could be accessed quite easily but later sea erosion near no. 3 level at the western end of the ledge has now cut away the edge of the footpath and made that too dangerous (now, in the year 2000, collapsed no. 3 level is visible in the face of the sea-cliff). At a later stage in the history of the fire (2 February, 1974) there was an eastward extension towards the direction of the adit (No. 4 Level) Cole (1975). I saw smoke emerging from fissures in the entrance region of No. 4 level. There was not indication of any fire deep in the adit, however. I did not personally see flames at the surface at any stage, only smoke, but I did not visit it frequently and a significant area of shale in the cliff was reddened as shown in the photographs

The geological aspects of the cliff fire were described by Doug Cole, then a research student at southampton University. On one occasion the local television came with Doug and myself to the cliff to film the fire.

Here is a letter by Dr. Cole to the Times newspaper.

A Burning Cliff
From Mr D.I. Cole

In view of the present energy crisis and the recent letters concerning the distillation of oil from oil shales, your readers might find interest and coincidence in the fact that a possible energy source in the form of a 3ft thick seam of oil shale, is at present undergoing spontaneous combustion. This oil shale outcrops on the coast of the Isle of Purbeck, Dorset. It has also been found at various localities in the Weymouth area. It is apparently burning as a result of the oxidation of pyrite, contained within the oil shale, which generates heat, although further studies are being made. As a result of this natural process, a 30ft cliff section above the oil shale has been baked in areas, and several small fumeroles are to be seen emerging from the cracks in the cliff. Temperatures near the oil shale were found to exceed 500 degrees C. The value of this oil shale should not be under estimated, since a company named the Kimmeridge Oil and Carbon Company obtained an average of 66 gallons of oil per ton of shale by distillation, in the early nineteenth century. Only three similar instances of "burning cliffs" in Dorset have been cited, occurring in 1751, 1755 and 1826 [but note also the Lyme Volcano of 1908], which at the time were compared closely to volcanic activity. Could, therefore, this present "burning cliff" coinciding as it does with the present oil. crisis, be a natural warning that the time has come to cease squandering the earth's resources of irreplaceable fuels and concentrate upon sources of energy such as nuclear and solar?

Yours faithfully ,

D. Cole ,
Department of Geology,
The University,
southampton, November 29, 1973.

There are about 21m of shale of the huddlestoni and wheatleyensis Zones of the Kimmeridgian succession exposed in the cliff section here(Cox and Gallois, 1983). The sequence includes the Blackstone (0.9m) and, a short distance above it, the Rope Lake Head Dolomite Band. There is another thin stone band higher in the cliff. The dip is 6%° to the northeast Cole (1975). The area of cliff affected by combustion is between the cliff top and the mining ledge, which Cole (1975)estimated to be about 7m above the foot of the cliff. This area of cliff includes the Blackstone which lies just above the base level of the ledge. Clearly the Blackstone was at one time removed directly from the ledge but it is not now much exposed at the back of the ledge because of fallen shale debris. It is conspicuous in the cliffs on either side of the mining ledge.

Areas of shale in the cliff above the Blackstone were burnt to a reddish-orange colour. There were several small fumeroles present in joints and cracks located in the shales and in the stone bands. The effects of the fire did not extend inland for more than 3m., where fumeroles were located in fissures of landsliding origin. The fissures did not exceed 0.3m in width Cole (1975). The scree showed evidence of baking. Certain parts of the cliff and scree were found to have temperatures in excess of 500%° C, with red heat noted at approximately 0.5m below the scree surface Cole (1975).

The fumeroles seemed to emitting several gases, of which sulphur dioxide and water vapour were prominent. Associated with the gases were deposits of fine sulphur crystals and a black tarry oil and encrustations of black tarry oil, salammoniac (ammonium chloride), gypsum, hemi-hydrate or bassanite (plaster of Paris) and anhydrite, which were located around the fumeroles. Cole (1975) determined these minerals by X-ray diffraction. He found the Blackstone to consist of the clay minerals - illite and kaolinite with quartz and calcite and with some pyrite (and has 6 - 9%% sulphur). Red-baked shale consists of illite, quartz and calcite with some hematite (which produces the red colour). Kerogen forms the main component of the Blackstone with bitumen forming only a minor component (Teichmuller in Cosgrove, 1970). Experimental combustion by Cole (1975) showed a 60%% volatile content.

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Clavell's Hard Fire continued - The Cause of Combustion

As noted above, most of the combustion of the Blackstone was apparently taking place at the base of the terrace, where it was obscured by the scree of shale. It has been rumoured that the fire did not start naturally and was started by a bonfire of some schoolboys. However, it seems unlikely that the Blackstone in situ was directly accessible to ignition by a fire, particularly in the middle of the ledge where so much scree is present. Certainly, any intentional effort to set fire to the Blackstone would not have been here. It remains possible, however, that a fire on the ledge could have ignited some fallen bituminous shale debris and the fire subsequently spread back to the Blackstone.

Cole (1975) argued that this was a case of spontaneous combustion like oil-shale fires elsewhere. There is pyrite in the Blackstone which is fine-grained (2 - 10 microns in diameter) and disseminated Cole (1975), although quite large nodules of pyrite also occur in the bed. At Burning Cliff, Holworth House Buckland and De la Beche (1836) it was suggested that oxidation of pyrite provided the heat for initiating the combustion of the oil-shale. Cole (1975) used this theory to explain the combustion at Clavell's Hard. Pyrite oxidises to ferrous sulphate, with the formation of sulphuric acid; ferrous sulphate is then oxidised to ferric sulphate, which in turn further oxidises the pyrite. The oxidation rates can be increased by biological activity, principally the actions of a thiobacterium,Tiobacillus ferrooxidans, and those of an iron bacterium, notably Sphaerotilus ( Kuznetsov et al., 1963 ; Baas Becking et al., 1960). A study of spontaneous combustion in coal (Moore, 1947) showed that the possibility of oxidation was increased both by the coal being in the form of small fragments and the presence of moisture. Cole (1975) pointed out that this may be applied to the Blackstone fire at Clavell's Hard, since a small landslip broke it down into small fragments, as indicated by the shale fragments of less than 3 cm. diameter in the fissures associated with this landslip. He found the shale fragments to have a higher moisture content than the adjacent rock. As mentioned above, the site where combustion was occurring was restricted to an area obscured by scree deposits of shale. These scree deposits, with fragments of less than 20cm diameter, retained a high moisture content which could have facilitated the continuation of pyrite oxidation in the underlying Blackstone, thus accounting for its limited lateral extent according to Cole (1975). Other factors such as the retention of heat by the blanket of shale debris may have been involved.

Once started, there seems to have been a relationship to high rainfall Cole (1975). The extension eastward and increased fumerole activity seemed to be related to phases of considerable rainfall. The Charmouth fire of 1751(Woodward, 1911) was apparently related to "sudden rains" and the Holworth "Burning Cliff" had combustion increased by both rain and sea-water (Damon, 1884).

The exact date of combustion commencing is not known but post-dates 18 January, 1972 and probably started between Spring 1972 and Autumn 1972. Combustion had practically ceased by 7 August 1974 (Cole (1975).

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Kimmeridge Oil Shale Fire - Clavell's Hard

- New Investigations in 2008

A group from Delft university, researching on oil shale fires, hold a discussion on the cliff edge above Clavell's Hard, Kimmeridge, Dorset, 2008

Jaya points out the site of an old fumerole above the cliff fire at Clavell's Hard, Kimmeridge, Dorset, 2008

A group from Delft University of Geotechnology, the Netherlands, are ready to make an electrical resistance investigation of the Kimmeridge oil shale in a meadow, northwest of Clavell's Hard, Kimmeridge, Dorset, 17th July 2008

Jaya Kisoensingh and Steve Etches hammer in electrodes in preparation  for an electrical resistance survey in a meadow northwest of Clavell's Hard, Kimmeridge, Dorset, 17th July 2008

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Burning Cliff, Holworth, Ringstead Bay, Near Weymouth, 1826.

Ringstead Bay from White Nothe

Ringstead Bay, viewed westward from the Chalk plateau of White Nothe. The slumped cliff of vegetated Kimmeridge Clay at the head of the bay, on the right, is the site of Burning Cliff. Beyond it, in the distance is Ringstead with Ringstead Ledge quite prominant. The third west of the three headlands is Bran Point which marks the main Corallian cliff section of Osmington Mills (photograph by Gareth Lloyd in the 1980s).

Site of Burning Cliff, Ringstead

The opposite view from the beach in Ringstead Bay looking east to White Nothe (photograph 1981, by the late Dr Stan Cockett, then of Burmah Oil Exploration Co.). The vegetated slumped cliffs where the fire took place can be seen. The unconformity with Upper Cretaceous Gault over Jurassic strata is well-known.

Location map for the Burning Cliff at Holworth, Ringstead Bay, near Weymouth, Dorset, England

Burning Cliff (SY 762815) is on the Kimmeridge Clay outcrop at the back of Ringstead Bay east of Weymouth as shown on this old map of Damon (1884) . It is just west of the fault, just west of Holworth House and near White Nothe (White Nore on the map). Originally referred to as Holworth Cliff (Damon, 1884), it is now an area of landslide with scrubby vegetation and Kimmeridge Clay visible here and there. There is little sign of the cliff-fire for which it is famous. The Kimmeridge Clay here is on the upthrow side of a fault which places it in contact with the Purbeck Formation to the east (beneath Holworth House). There is a footpath down the cliff here and the place is easy to find because it is directly west of the Portland and Purbeck stone outcrops and the stone debris. (Please note that although the old map provides a reasonable general picture of the geology here it has, of course, been superseded by later mapping, and if you are interested in more accurate detail then see the latest edition of the Weymouth Sheet, 342 of the British Geological Survey ).

The fire broke out in 1826 in the Blackstone and associated bituminous shale and continued for several years (Arkell, 1947). The fire was supposed to have been started by heat generated by the decomposition of pyrite, a common constituent of the bituminous shales and especially the Blackstone (Damon, 1884). It gave off sulphurous fumes which in certain circumstances could be detected for several miles.

The cliff-fire was in progress when Buckland and De la Beche visited the district in 1829 for the preparation of their paper on the geology of Weymouth. Here are the comments of Reverend William Buckland (Reader in Geology at Oxford) and De La Beche:
"We have at this moment before our eyes the pseudovolcanic phenomena that are exhibiting themselves ... near the east extremity of Ringstead Bay ... This pseudovolcanic combutions began in September 1826, and during a period of many months emitted considerable volumes of flame, probably originating in the heat produced by the decomposition of the iron pyrites with which this shale occasionally abounds ... This pseudovolcano at Holworth commenced in the face of the cliff about twenty feet above the sea; its combustion was proceeding slowly when we saw it in September 1829, and it emitted no flame .... The extent of the surface of the clay which has been burnt does not exceed fifty feet square. Within this space are many small fumeroles that exhale bituminous and sulphureous vapours, and some of which are lined with a thin sublimation of sulphur; much of the shale near the central parts has undergone perfect fusion, and is converted to a cellular slag. In the parts adjacent to this ignited portion of the cliff ... the shale is simply baked and reduced to the condition of red tiles like on the shore near Portland Ferry."

Some of the features referred to here are like those seen in the beach-fire described above. There is sulphur deposited at fumeroles and there is cellular slag, although black and coke-like rather than like hard siliceous furnace slag. Buckland and De la Beche refer to the extent of the surface burnt not exceeding 50 feet square. I suspect this means 50 feet by 50 feet, rather than 50 square feet. If it is the former that is 232 square metres, but if the latter only about 5 square metres, which seems very small. The Clavell's Hard fire was of 75 square metres area (Cole, 1975) and the present beach fire is of 72 square metres. Of course there could have been a small surface appearance resulting from a larger underground fire but the note about several small fumeroles makes the larger figure more likely.

Another description, this time in 1884 by by Robert Damon, fossil collector and author of Weymouth, suggest that it was, indeed, a major fire. This author seems to have seen it in his early days and desribed it as follows:

" This phenomenon first made its appearance immediately after a spring-tide, which being attended with strong southerly gales, the waves broke over the cliff, and the water producing a decomposition of the iron pyrites in the shale was supposed to have been the cause of ignition. If we remember rightly, there had previously been a slip in the cliff, by means of which a fresh portion of it had become exposed. Whatever might have been the exciting cause, certain it is that when once ignited it received increased force from heavy rains or sea-water. The cliff continued in a burning state several years, during which period it formed an object of considerable interest. On acquiring fresh energy, it threw out volumes of dense and suffocating smoke, which from its specific gravity, seldom rose high into the air. This was followed by bluish flames, rising at times so far above the cliff as to be visible from Weymouth. Throught he cracks spread over the surface by the ascending heat the burning stratum beneath was seen. The fissures and other openings were covered with deposits of sulphur. Some people expressed alarm at residing near a supposed volcano, but we need scarcely say it was unattended with explosive noises, eruptions, and the other phenomena ordinarily accompanying volcanic activity. The combustion only ceased when the inflammable portion of the shale was consumed."

Presumably the cliff has now eroded back beyond the limits of the fire, or, perhaps, most has gone but the relics have been covered by further landslips and vegetation. By 1898 Strahan said that the "burnt fragments of shale which formerly abounded having almost all been washed away." Dr. W.J. Arkell writing for the 1947 memoir, which was in preparation in the 1930s before the Second World War, commented that all traces have now disappeared, excepting for an occasional clinker-like pebble on the beach. It is difficult to find anything here now.

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Burning Cliff - Holworth - 1827 Account in Full

Location of the Burning Cliff at Ringstead Bay, Dorset

To provide more detailed information, there follows a full account of the Burning Cliff from Anonymous (1827) in "The Mirror of Literature, Amusement and Instruction", Saturday, June 9, 1827. No. 257, Price 2d. This was reproduced by this journal from "The Topographer", No. XXII, and that article, in turn, comes from the "Gentleman's Magazine".



Public curiosity having been strongly excited by the extraordinary phenomenon of the appearance of a volcanic eruption on Holworth Cliff, we copy the following scientific observations and interesting particulars, in illustration of this singular operation of nature, from the Gentleman's Magazine of this month. Holworth Cliff forms the southern boundary of a farm called South Holworth, (anciently written Oleworth, Holeworth, and Holwerde,) the property of J. J. Lambert, Esq. of Dorchester; it is situate about two miles eastward of Osmington, and forms a very prominent object from Weymouth Bay.

This cliff is composed of a blue slaty lime-stone [Kimmeridge Clay], somewhat similar to the Charmouth Cliff, [Lower Lias Shales] but exhibiting a more advanced state of decomposition, yet bearing a much stronger and closer affinity to the Kimeridge coal [the Kimmeridge Blackstone , an oil-shale], and indeed may be fairly considered as the connecting link between them. This stone, which is used as an article of fuel by the neighbouring poor, is inflammable, and of a strong bituminous and sulphureous nature; it burns free, and produces a very brilliant light, but emits at first, and until the gaseous particles are all evaporated, a very offensive smell; it afterwards continues to burn for a long time pleasantly, and notwithstanding the disagreeable effluvia arising from its first, igniting, it does not appear that any injurious effect has ever attended by the use of it [actually the ash is carcinogenic]. It does not burn entirely to ashes, but leaves a substance like burnt slate [reddish], which is, after a time, reduced to powder, on being subjected to the action of the atmosphere. It is worthy of remark, that blocks of this stone which have been exposed to, and washed by, the salt water, burn better than what is recently taken from the cliff.

The soil contains Pyrites, Marcasite, Cornu Ammonis [ammonites], with remains of other shells and Belemnites. These substances are not found in regular strata, but are interspersed in masses, through the soil, which is impregnated, more or less, with bitumen, to an uncertain depth. There are occasionally found pieces of a darker substance of stone, resembling charcoal, but much harder [what is this - jet, lignite?].

About twelve years since [1815], that portion of the cliff which has lately attracted so much of public curiosity, was observed to change its appearance, and a quantity of ground, about an acre and half in extent, gradually sunk about thirty feet [about 10m.] below its former level, in a direction towards the sea, and remained there for a short period; on this detached piece of ground there was a cottage, inhabited by a fisherman (named Baggs) and his family,who prudently left it after perceiving the first symptoms of an alteration; however, the cottage remained, with the exception of a slight crack in one of the walls, perfectly entire. Sometime afterwards this piece of ground made a further gradual slide in the same direction, carrying the cottage with it, without any additional injury and during a period of nearly three years from its first removal, it occasionally continued its sinking progress,downwards, to the extent of nearly five hundred feet [about 150m. - this seems to be an overestimate of the height of the cliff, unless it was then much higher, but the great descent implies that Mr Baggs' cottage was originally almost at the top], when it made a stand, exhibiting the entire cottage, with its accompanying garden, well stocked with gooseberry and currant trees, and various vegetables, all in the most flourishing condition, and still retaining its position. The cottage has been lately [towards 1826 or 1827] taken down, the materials being removed, by its former occupier, to build him another habitation on a spot near, but presumed more secure and apparently less liable to a similar disaster. The fruit-trees and vegetables continued in an equally thriving condition, until the late eruption; but now the numerous trespassing visitors have nearly obliterated every vestige of so remarkable an occurrence.

As portions of the cliff along the whole extent of this coast are constantly falling down, particularly after heavy rains.and, breaking up of frost, this slide [of 1815-1816?], as it is called, did not at time excite any particular notice, although so extensive, but was looked on as merely an incident natural to the peculiarity of the soil; nor was there any thing for some time after this detached portion of cliff had become stationary which caused any remark, until about five years ago [1822], a vapour was observed to exhale from that side of it facing the sea, and the same appearance has occurred occasionally since, at irregular intervals, particularly after heavy rains, varying materially in extent and also as to locality. It has been noticed that the vapour has been more offensive, and has issued from the interstices in much larger quantities, at the spring tides than at other times; but that the greatest effusion of smoke has occurred about the vernal and autumnal equinoxes.

[In November 1824, the "Great Gale" struck. This was a hurricane with a storm surge temporarily raising the sea level 2 or 3 metres above high spring tide level. It would have covered the beach and introduced seawater into the lower part of the landslide.]

In the months of September and October, 1826, a very considerable portion of vapour was, for the first time, observed to rise from two or three apertures, on the summit of this cliff, and continued to issue therefrom for some time, until fissures were opened by its contending strength, in the side of it large enough to permit its escaping in that direction. The quantity exhaling from the summit was (to use the language of an eye-witness) as much as is usually caused, and passes out of a chimney, at the first lighting of a common fire. On a calm day it has been seen to rise in a majestic column to the height of twenty feet [6m.], and had a very curious and imposing effect in such a situation; since. the vapour has forced down a portion of the cliff, and found an uninterrupted passage through the fissures thus opened, it has, with scarce any intermission, continued to exhale, only varying as before-mentioned in the number of apertures, from four to ten, and in the space of ground over which they are extended.

On the l5th of March, 1827, Nicholas Baggs observed the vapour arising from the side of the cliff to be in larger quantities than usual at that spot and having occasion for fuel [i.e. Kimmeridge Blackstone or oil-shale], curiosity urged him to direct the persons he employed for the purpose, to dig at that part; after removing a small portion of the surface, they were very much surprised at seeing fire, and what at first sight seemed to them a small flame. The appearance of flame was momentary - it died away almost as soon as it became visible, and there has not been the least semblance of flame since, except on the application of some combustible material, to either of the fissures in the rock in which the fire was perceptible, which immediately ignited. Dry sticks, or any inflammable substance, would, on being thrust into any of the apertures from whence smoke issued, instantly kindle and produce flame, and remain burning as long as fed with such matter; but as soon as the substance so applied was consumed, the flame would invariably die away instantly. It is necessary to state, in consequence of the multiplicity of idle reports of a contrary tendency [see reports given above], that there never has been the least flame issuing spontaneously from any part of the cliff, since the first appearance of fire.

The apertures from whence the vapour or smoke issue, are about forty feet [12m.] above high water mark; the appearances within the interstices of the rock, at the depth of five or six feet [about 2m.], were very similar to that of the lower part of a lime kiln, in its most active progress of operation. The massy blocks of stone on fire, displayed at first sight a most vivid and somewhat awful appearance; throwing out a very intense heat, accompanied with a powerful sulphureous effluvia, highly oppressive, so much so, as to cause a visible effect on the respiration of those persons who remained any length of time within its influence [I can verify that fumes of cliff fires can cause a dizzy sensation].

This interesting appearance was visible five or six days, and would probably have remained so much longer, but the unadvised curiosity of the learned as well as the unlearned, eager to dive into the secret workings of nature, induced them to apply crow-bars, pick-axes, and other powerful implements, for removing the surface, as well as portions of the rock, any way offering an obstacle, in order to ascertain (as they imagined) the cause of this wonderful phenomenon; which, after all their efforts, proved fruitless; nature, in her operations, being too subtle and impenetrable for human ingenuity to developed her designs. The consequence is that, owing to the quantity of rock and soil removed from the principal apertures, a very large portion of the upper part of the cliff being partially undermined has fallen down, and buried the precise spot that first excited so large a share of curiosity; and, although the quantity of vapour now issues is not so profuse as originally, still the exhalation is considerable, and emits a very powerful exhuvia from three apertures which proves how vast a mass of fire exists, mouldering beneath this heap, feeding on the perishable mementos of a former world. The outward surface of the rock, at this part of the cliff, is very hot, as well the soil around the apertures, and small fragments of the stone retains very considerable degree of heat for a long time, after being detached from the larger blocks.

The ground shakes with a trifling and sudden pressure of the foot, and even by a blow with a stick, which evidently proves the internal recesses of this mass of earth to be hollow, and of course dangerous to a certain degree. It is very probable, that at some future period, perhaps not very distant, after the partial consumption of the materials feeding this immense body of fire, the present crust or surface may sink down, and exhibit all the incidental peculiarities of an extinct volcano; or possibly astonish us, with the more awful characteristics of an existing one, in active operation.

Previous to the disruption of this portion of cliff from its neighbouring soil, tbere was a spring of excellent water, constantly bubbling out a copious crystalline stream, but which this convulsion entirely suppressed. A little water now oozes out from another part of the adjoining cliff, and immediately hides itself amongst the soil, being as it were ashamed of its insignificance. About one hundred feet [about 30m.] from the summit of this disjointed cliff, where the exhalation issued last August, there is a hollow formed by its separation from its former site, a pond of stagnant water [the usual pond of a rotational landslide], abounding with the common water lizard [newt?]. There are not at this time any indications that will warrant the expectation of a violent eruption, nor are the peculiar local properties of the soil of such a description as to excite any alarming apprehension. After a time, it is very probable the vapour may partially subside, till another convulsive effort of nature may shew the wondering visiter the astonishing working of her hidden and inexplicable machinery. That there is an extensive body of subterraneous fire accumulated here, is too evident to be doubted; the least casual observer cannot justly draw any other conclusion from even a superficial view, and it is to be hoped that the mighty operations in constant progress underneath will never meet a resisting impediment to a ready vent, upwards, for the free discharge of its in increasing and superabundant effluvia.

The slide before alluded to which happened in the year 1816, was unquestionably caused by the operation of subterraneous fire [unlikely!], being the first visible effects of the impulse upward produced in consequence of its having met with an obstruction to a free conducting channel beneath, and which proportionally increases the force of that dreadful element [erosion of the foot of the clay cliff was the probable cause of the landslide, but now with a large beach there is little erosion and little landsliding here.]

It being ascertained that the cliff contains a mixture of pyrites, sulphur, and iron ore, the effect to be produced on such a combination of materials by the action of salt water, must be precisely that which has happened [probably true]. There are instances on record of similar occurrences from like causes, viz. in the month of August, 1751, at Charmouth in this country; and at the mouth of the river Shannon in Ireland, in the year 1753; and in the Philosophical Transactions mention is made of a like circumstances in Caernarvonshire.

There is no doubt of communication of salt water with the interior part of this cliff, perforating through the loose pebbles at its base, and which communication originally effected the separation and removal of this mass of earth from its former situation; as a proof of it, if proof were wanting, it has been observed that the spring tides, and more particularly the equinoctial tides owing to their increased fluxes coming more immediately in contact with these active internal agents) have invariably produced very visible effects on the discharge of vapour from this cavern; as at these periods a much larger quantity issues out, and a far stronger effluvia is emitted than at any other times.

The whole line of coast exhibits in the various strata, and numerous alluvial deposits contained in them, very remarkable features of violent convulsions; and although no record exists to inform us of the precise period of their occurrence, it is not less certain and demonstrable, that they have happened, leaving incontestable proofs of their amazing effects in the many varied contortions of the soil, intermixed with such a vast profusion of organic remains, with other strong concurring testimonies.

Footnote: In Holworth and the neighbouring cliffs, the Nautilus, Cornu Ammonis, Pecten, Pinna, Nomia, Trigonia with vertebrae, and other fragments of the Ichthyosaurus, etc. etc. are frequently found. This coast presents a wide and interesting field for the geologist and natural philosopher.

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Red mudstone from an oil shale fire at Portland, Dorset, and comparable Roman burnt mudstone used for Opus Sectile at Fishbourne

The Kimmeridge Coal or oil shale crops out beneath loose stone and rubble between tide marks off Castleton (Strahan, 1898) . The bed was recorded as 25cm (10 inches) thick and used to be dug for fuel at one time. It was dug "especially eastwardes of Her Majesties Castill" in 1594 (Arkell, 1947) . Later, in the 19th century, it was quarried for chemical treatment (Damon, 1884)

There seems to have been a major oil-shale fire in the past in this material, somewhere on the west side of Portland Harbour. Red-burnt shale, appearing like red tiles, can still be found in Portland Harbour Beach south of Small Mouth in the region near the Chesil Beach Centre. It was originally reported to be present at Small Mouth by Buckland and De la Beche in 1836. The source is presumably an outcrop seen by Damon (1884). He stated that: " A bed of the shale presenting the appearance of burnt tile is exposed at extreme low water on the shore at Portland, near the Castle and extending to the north side of the Chesil Beach from which the bituminous parts have been exhausted or burnt out. This altered character resembles the condition which was presented in the cliff at Ringstead, after the memorable combustion that occurred in the year 1826. As the shale could not have ignited without oxygen, no explanation appears more probable than that the bed in question must at one time have been above the level of the sea. The fossils found in this singular bed are similar to those of the paper-shales at Ringstead, compressed Ammonites, Discina, Cardium, Astarte, Lucina, Pecten etc., though not always distinguishable." If it extended from the Castle to the Chesil Beach, this was a much larger natural fire than at Burning Cliff, or Kimmeridge more recently. It was probably the largest oil shale fire on the Dorset coast of which there is any trace. It is a pity that the date of the fire is not known. Apart, of course, from being above sea-level, they are normally in a cliff with some landsliding or collapse. To have had a sufficiently low sea-level for this to have been the case, the fire could hardly have been much younger than Neolithic (round about 4000 years ago) and could even have been late Pleistocene (Devensian - before 10,000 years BP).

A comparison is shown above with red-burnt Kimmeridge mudstone much used by the Romans for Opus Sectile (a type of ornamental flooring tile in mosaics, and usually cut into triangles) at Fishbourne Roman Palace. The Roman material is remarkably similar and with similar fossil content. It does not so closely resemble the cliff-fire material which is visible at present at Clavell's Hard east of Kimmeridge Bay. It seems probable that the Romans used the burnt mudstone associated with the oil shale here at the Isle of Portland. More work on this has been undertaken by geoarchaeological Pari White.

For more information on Portland Harbour please see the Portland Harbour webpage.

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Lyme Volcano - Burning Cliff East of Lyme Regis, 1908

(See also the: Lyme Regis to Charmouth webpage;
the: Lyme Regis Bibliograph.)

The Lyme Volcano at the Spittles, Black Ven, Lyme Regis, Dorset, 1908

An old postcard showing the Burning Cliff at Lyme Regis, Dorset in 1908, courtesy of Jane Evans

A map, published by Jukes-Browne, showing the location of the 1908 'Lyme Volcano', an oil-shale fire at Lyme Regis, Dorset

Blue Lias top and Lyme Volcano

Geological map - The Spittles, east of Lyme Regis

A famous cliff-fire occurred in 1908, east of Lyme Regis (see below for old accounts of this). This "Lyme Volcano" or "Burning Cliff" was situated at the top of the lower cliff at a height of just over 30m about halfway between Black Ven and Church Cliffs, Lyme Regis, at the place shown in the photograph and the map above. The locality is at the western end of The Spittles and just east of the end of Spittle Lane. The fire was on a small small plateau or terrace above the steep, lower 30m sea cliff (there are lower-angle, landslipping cliffs above) seems to have been only 10 or 20 metres back from the top brink of the 30m sea-cliff. For more information on the geology of this area see the Lyme Regis to Charmouth webpage.

Jukes-Browne (1908) published a large-scale map which showed its position as small a burning mound, adjacent to and just northeast of a landslip. There is much debris on the beach slightly southwest and a major landslide was clearly in progress. Jukes-Brown said that the burning mound has no connection with the landslip except that the two are in close proximity. The burning mound, though, did consist of fallen debris of shales, iron pyrites and cementstones which have come from the beds exposed in the next, and smaller cliff above. Two photographs, which Jukes-Browne published, and taken from the west and southwest, show a plume of smoke rising from the mound. One of these photographs has been reproduced by Ensom (1998, p. 22).

As Ensom (1988) commented, cliff falls are often precursors of spontaneous combustion, when smoke and steam are seen rising volcanic-like from fissures in the cliff. Oxidation of pyrite (ferrous sulphide), which may be enhanced by bacterial activity is believed to trigger the spontaneous combustion of bituminous shales. It seems unlikely that this particular burning cliff would have been ignited by human activity considering its location within a substantial landslide area and general ignorance amongst the public at the time about the exact location of bituminous shales. However, as we shall see, below, it is possible that the fire was subject to "improvement" by human activity. With a narrow plume of white smoke it seems that it was quite like the Clavell's Hard fire and the beach fire described above.

As shown in Lang's (1913, published 1914) map, the fire took place on the Shales-With-Beef of the Sinemurian of the Lower Lias. The zone is the Caenisites turneri Zone (House, 1993). This is probably the most organic-rich part of the Lower Lias but it does not have true oil-shales like those in the Kimmeridge Clay. The "beef", fibrous calcite, is a common product of burial diagenesis of organic-rich shales that contained aragonite. The Lias is known to contain beds with up to 7.36 wt% TOC (Total Organic Carbon - note: less than total organic matter) and is an oil source rock for the Wessex Basin. In comparison the Kimmeridge Clay attains 20.48wt% TOC (Ebukanson and Kinghorn, 1990). However, as Jukes-Browne (1908) noted the debris has fallen from the next cliff above. It seems to have included the uppermost part of the Shales-With-Beef and the argillaceous limestone and dolomite nodules known as the Birchi Nodules or Firestone Nodules. For more on the Shales-With-Beef see Lang, Spath and Richardson (1923) and Bellamy (1980).

The slip and the consequent formation of the mound took place early in January, 1908, and the mound began to smoke about January 19th, soon after which date reports of a volcano at Lyme Regis began to circulate in the newspapers (Jukes-Browne, 1908 ). Conditions were very favourable for combustion. Pyrite was abundant and the mass was loose and saturated with the winter rains. This helped the exothermic oxidation of the pyrite and some of the shale when dried in an oven could be ignited.

Jukes-Browne (1908) recorded a change in June of the same year:

"When smoke began to issue from this mound, it must have presented some resemblance to a volcano, and the combustion continued more or less vigorously from January to June, without any other change taking place. Mr Cameron relates that on the morning of June 10th, he and the Vicar of Lyme Regis were on the ground close to the burning-mound, which was smoking as usual; but about half-past one on that day he was told that a landslip had taken place, and that the mound had been split in two by a fissure, so that its interior was exposed, looking like the inside of a brick-kiln, from the baked appearance of the shale and stone.

The landslip took place about 1.15 p.m. on June 10th. As above stated, Mr Cameron was on the cliffs about an hour before it happened, and he did not notice any signs of an impending change. No new fissures had appeared, and no movement was taking place, while the boats were busy as usual taking stone from the limestone beds at the foot of the cliff.

Eye witnesses stated that three minutes after the last stone-boat had left, a portion of the cliff suddenly gave way, and the large mass, weighing many thousand tons, fell forward onto the beach with loud rustling and rumbling noise, which was plainly heard in the town, while a cloud of sulphurous smoke issued from the burning mound..."

Quarrying of the Blue Lias ledges, as the quarrymen called them, by pick and bar was believed to be a contributing factor in increasing cliff erosion. The argillaceous limestone was taken away by boat to the cement works (would this be the cement factory at Charmouth?). It had been stopped at Church Cliffs but not just here. Another factor was water running off the Timber Hill area and disappearing into cracks and fissures on the Lias cliffs. There is also dry-weather contraction which gives progressive slow downslope movement. The fall referred to took place in dry conditions. The present author has seen major dry weather falls from the Lias clay cliffs east of Charmouth and it has been mentioned by others as occurring in this area. It is something of a potential hazard, because more people are likely to be on the beaches in such conditions.

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Lyme Volcano - Additional Old Records

Here are some further details of the cliff-fire from Woodward (1908).

"Towards the end of January last [1908] the inhabitants of Lyme Regis were somewhat alarmed by the announcement that a portion of the cliffs on the eastern side of the town, towards Black Ven, was "on fire"; a "Full Report of the Volcanic Eruption" was soon afterwards published in the Bridport News for January 24 [1908]. It was then stated that on Sunday, January 19, " dense vapour appeared at intervals to rise from a mound on the edge of the cliffs, about half-way between Lyme and Charmouth, " and that the burning portion "consisted of a large fallen mass of the cliff which had at some time since slipped away from the body of the cliff." Mr. A. C.G. Cameron, who was at the time resident at Lyme Regis, explained that the case was one of spontaneous combustion, due to the decomposition of iron pyrites and the consequent generation of heat sufficient to ignite the bituminous shales of the Lower Lias.

Iron pyrites and marcasite (rhombic iron pyrites) are found more especially in the Lias shales. They are most abundant in the shales of the Lower Lias. At Black Ven, near Lyme Regis, there is a 'Metal bed' and material derived from this and other layers was formerly collected during the winter months for the preparation of copperas (sulphate of iron), sulphuric acid and sulphur [Copperas or melanterite was also obtained from the cliffs of Bournemouth and Brownsea Island in Poole Harbour]. Examples of marcasite are sold to visitors as 'angels' wings.'

The burning cliff was also examined by Mr Charles Grover of the Rousdon Observatory, Lyme Regis in February, 1908. Copies of letters and transcriptions have been kindly provided by Mr Jerry Grover. The originals are at the Norman Lockyer Observatory. E.M. refers to English Mechanic Magazine, to which, according to Jerry Grover, Mr Charles Grover was a prolific contributor. Here are some extracts.

Letter from Mr Grover "8 February, 1908
Dear Mr Richards,

.......... I went to see the Burning Cliff on the 6th and have sent an account to the EM which I expect will come out next Friday - it is an immense body of Solid fire - no flame, and the heat is intense - if I can get a photo I will send you one, though there is not much to see only a little cloud of Steam outside - the fire is within and the Cliff too hot to stand on."

"12 February, 1908.
Dear Mr Richards,

This is not a reply to your kind letter that will follow later on, but I now send you a print of the Burning Cliff - as I said before there is not much to see, but a lot to feel - the hole with the crow bar was made where the jet of steam is coming out just below the arrow, and the Cliff is inside a mass of dull red fire - see the EM on Friday - the owner of the negative is Mr. W Down C/o R Southwood and Co Broad Street, Lyme Regis

Yours very truly,
C. Grover"

In February of the following year, 1909, Dr. W.D. Lang, the great specialist on the Lias, wrote to the Geological Magazine under the pseudonym "Passer Venensis". He seemed mildly irritated by the way the "Lyme Volcano" was being used as a tourist attraction!

The Burning Cliff Near Lyme Regis

Sir, - Now that the spontaneous combustion at the Lyme Regis end of Black Ven has been mentioned in your pages, I beg to be allowed to point out a possible source of misconception to visitant geologists as to the extent of the burning. But first let me make it clear that my statement is only hearsay, and may be mere gossip; for being otherwise busied at the time, I was unable to investigate the matter. Its bearing, however, on the magnitude of the phenomenon is obvious and for that reason considerable.

The cliff took fire early in 1908. Notices, descriptions, and explanation s appeared in various papers, local and otherwise, and enterprising shopkeepers in Lyme took photos and exhibited them as picture postcards, which they sold as mementos of 'the volcano'. The advertisement attracted visitors to Lyme, and evidently the burning cliff was a source of profit to the Lyme folk. In Charmouth, during April, 1908, it was common talk that when the 'volcanic' activity appeared to be subsiding, disappointed Lyme people poured paraffin on the cliff and relighted it. It is probable that, saturated with enough paraffin, any clay cliff would burn when lighted, and the effect would be commensurate with amount of oil used. If the paraffin was poured on the burning part of Black Ven, it has made if impossibe to judge the extent of the natural combustion and of its effects. Last April a beautiful specimen of burnt red shale was in the Coach and Horses Hotel at Charmouth, but the interest it would naturally have evoked was spoiled by the suspicion that it was the result not of the heated behaviour of Black Ven, but of the commercial ardour of Lyme speculators. It would be interesting if a future Lyme visitor would investigate the report and establish the truth. In August last the Charmouth world said that the Lyme people had over-reached themselves, and had some much of the 'volcano' that intending visitors stayed away through fear. This so unlikely that one is inclined to doubt the truth of the paraffin statement.

With apologies for much gossip, even though it contains a warning,
Passer Venensis

This was not the end of the matter. In August 1909 there was a further contribution to the Geological Magazine, this time by Mr Cameron.

"Mr. A.C.G. Cameron, writing from Harcombe Bank, Uplyme, February 9, 1909 (in reference to the letter of "Passer Venensis" in our February Number) expresses his convictiion that paraffin was thrown at times on the 'volcano'. He never witnessed such volumes of smoke arising from the mound of burning shale as are depicted on some of the picture postcards, and he concludes that if they did not touch up their photographs some of the photographers must have brought paraffin with to enliven the smouldering masses. Mr. Cameron adds that he has taken from the mound beautiful specimens of burnt red shale with ammonites, "not cooked with paraffin"."

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Charmouth Cliff Fires, 18th Century

There are old records of cliff fires at Charmouth, the famous centre for fossil collecting, near Lyme Regis. At Charmouth the bituminous Shales-With-Beef (Lower Lias), the source rock for the Wytch Farm oilfield, are at beach level west of the mouth of the Char to about the middle of Black Ven. East of Charmouth, at Evan's Cliff they are at about sea-level under the Black Ven Marls. The most likely place for cliff fires to have occurred (and perhaps to occur in the future) is thus west of the Char. However, with the Shales-With-Beef at the beach level it is not impossible to have had cliff fires east of the Char. There is, in any case, some bituminous shale in the Shales with Beef, especially in the central part.

Landslide in the Black Ven Marls at Evan's Cliff, Charmouth, Dorset, 16 Jan 2006, with fossil hunters congregating at the base

Landlides, which seem initiate cliff fires are common in the eroding cliffs on both sides of the mouth of the Char (and are of course, well-known in Black Ven). The photograph above shows a recent landslide in Evan's Cliff but with no cliff fire, at least not yet!

Damon (1884) and Woodward (1908) referred to cliff fires in the bituminous shales of the Lower Lias at Charmouth, east of Lyme Regis. Bishop Watson in 'Chemical Essays', part of Maton's Observations on the Western Counties, reported a fire in 1751. This took place among fallen masses of the strata. "There is in the lias cliff at Charmouth a good deal of pyrites, which took fire after a heavy rain, and produced an appearance of flame at a distance." Another fire took place in 1755. For more information see Stephen (1762). In 1890 similar combustion took place further east, and in the Daily Graphic of February 19 there appeared a picture of the 'eruption' of Golden Cap (Woodward, 1908). Ensom (1998) reported "steaming" cliffs at Charmouth in late 1987 and early 1988, but no actual combustion.

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David Meadows first contacted me by email about the oil-shale fire on the beach east of Kimmeridge. I am very grateful to Mr and Mrs Meadows for reporting their discovery and assisting me in making records, taking photographs and collecting samples from the debris of the fire. I am grateful to the late Dr Stan Cockett and Mr Gareth Lloyd for photographs of Ringstead Bay.

The letter from Mr Grover of Lyme Regis in 1908 about the Lyme Volcano has been very kindly provided by Mr Jerry Grover, to whom I am most grateful. I thank Mr. Anthony Hutchinson for providing me with a copy of "The Mirror" article.

I am very grateful to Pari White for help with geoarchaeological matters. David Rudkin, Director of the Fishbourne Roman Palace, was very helpful and kindly provided access to Roman Opus Sectile and other material.

I very much appreciate the kindness of Jane Evans for allowing me to reproduce an image of her postcard of the Lyme Volcano of 1908. This website is kindly run from the server of Southampton University. I much appreciate the advice and help of my daughter, Tonya Loades of Bartley West, Chartered Surveyors.

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References and Select Bibliography

For general references on the Kimmeridge Clay go to the Kimmeridge Bibliography. For more on the Lias of Lyme Regis see the:
Lyme Regis to Charmouth webpage;
the: Lyme Regis Bibliograph.



Arkell , W.J. 1947 (reprinted 1953). The Geology of the Country around Weymouth, Swanage, Corfe and Lulworth. (Explanation of Sheets 341, 342, 343, with small portions of Sheets 327, 328, 329) With contributions by C.W. Wright and H.J. Osborne White. Memoir of the Geological Survey of Great Britain, Department of Scientific and Industrial Research, H.M.S.O., London, 386 pp.

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Baas Becking, L.G.M., Kaplan, I.R. and Moore, D. 1960. Limits of the natural environment in terms of pH and oxidation-reduction potentials. Journal of Geology, 68, 243-284.


Bellamy , J.R.W. 1980. Carbonates within bituminous shales of the British Jurassic - Their Petrography and Diagenesis. Unpublished Ph.D. Thesis. University of southampton. By Dr. Jon Bellamy.


Buckland , W.A. and De la Beche, H.T. 1836. On the geology of the neighbourhood of Weymouth and the adjacent parts of the coast of Dorsetshire. Transactions of the Geological Society of London, series 2, vol.4, pp. 1-46.

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Cameron, A.C.G. 1909. The burning cliff near Lyme Regis. Geological Magazine, New Series, Decade 5, Vol. 6, p. 336.[brief discussion]


Coker, J. 1732. A Survey of Dorsetshire. (p. 42) London.


Cole , D.I. 1975. Observations on a burning cliff. Proceedings of the Dorset Natural History and Archaeological Society, for 1974, 96, 16-19. [A cliff fire in the oil-shale or Blackstone of the Kimmeridge Clay at Clavell's Hard, east of Kimmeridge Bay. It burnt from 1972 to 1974 and reddened an area of the cliff. Minerals formed at fumeroles of the fire include salammoniac, sulphur, gypsum, hemi-hydrate and anhydrite.]


Cosgrove , M.E. 1970. Iodine in the bituminous Kimmeridge shales of the Dorset Coast, England. Geochimica et Cosmochimica Acta, 34, 830-836. Abstract: Trace element, carbon dioxide and organic carbon analyses of a range of Kimmeridgian Shales show high correlation of the elements iodine and bromine with organic carbon. It is suggested that marine plant material incorporated with the sediment at the time of deposition is responsible for this association of elements. [Average value of iodine - 17ppm. Maximum 72 ppm. These must be amongst the most iodine-rich sedimentary rocks yet recorded.]


Cox , B.M. and Gallois, R.W. 1981. Stratigraphy of the Kimmeridge Clay of the Dorset type area and its correlation with some other Kimmeridgian sequences. Report of the Institute of Geological Sciences, No. 80/4, 144.

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Damon , R.F. 1884. Geology of Weymouth, Portland and the Coast of Dorsetshire from Swanage to Bridport-on-the-Sea: with Natural History and Archaeological Notes. 2nd ed., R.F.Damon, Weymouth, 250pp.


Ebukanson , E.J. and Kinghorn, R.R.F. 1990. Jurassic mudrock formations of the southern England: lithology, sedimentation rates and organic carbon content. Journal of Petroleum Geology, 9, 3, 259-280.

Ensom , P. 1998. Discover Dorset: Geology. The Dovecote Press Ltd, Stanbridge, Wimborne, Dorset. 89pp. ISBN 1 874336520


Grover , C. 1908. Letters mentioning the Lyme Volcano. Copies provided by Mr Jerry Grover. Details are given above.

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House , M.R. 1993. Geology of the Dorset Coast. Second Edition. Geologists' Association Guide No. 22. The Geologists' Association, Burlington House, Piccadilly, London, 164 pages & plates. Paperback. ISBN 07073 0485 7.


Jukes-Browne, A.J. 1908. The burning cliff and the landslip at Lyme Regis. Proceedings of Dorset Natural History and Antiquarian Field Club 29, 153-160. [by A.J. Jukes-Browne, F.G.S., read July 22nd, 1908. With 4 plates, including two photographs of the Lyme Volcano and one illustration of the Burning Cliff at Ringstead. With a map showing the exact location of the cliff fire, the burning mound.]


Kuznetsov, S.I., Ivanov, M.V. and Lyalikova, N.N. 1963. Introduction to Geological Microbiology. New York, pp. 139-140.


Lang, W.D. (alias - "Passer Venensis") 1909. The burning cliff near Lyme Regis. Geological Magazine, p. 89.

Lang, W.D. 1914. The geology of Charmouth Cliffs, Beach and Foreshore. Proceedings of the Geologists's Association, 25, 293-360. [With a diagram showing the Lower Lias succession of the area including the Blue Lias and the Shales with Beef, and also an excellent and detailed geological map of the coast at Charmouth, Dorset. It indicates the position of the 1908 Burning Cliff or Lyme Volcano.]

Lang, W.D., Spath, L.F. and Richardson, W.A. 1923. Shales-With-'Beef', a sequence in the Lower Lias of the Dorset Coast. Quarterly Journal of the Geological Society, 79, 47-99.

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Mansell, J.C. 1967. Kimmeridge and Smedmore. [Booklet published by Major J.C. Mansell, owner of Smedmore Estate and Kimmeridge, with information on oil-shale industry at Kimmeridge.]


Maxwell, D. 1927. Unknown Dorset.[With reference to oil-shale workings.]


Moore, E.S. 1947. Coal. 2nd Ed., New York, pp. 326-327.

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Sokol , E.V., Novikov, I.S., Vapnik, Y and Sharygin, V.V. 2007 (presented 2006). Gas Fire from mud volcanoes as a trigger for the appearance of high-temperature pyrometramorphic rocks of the Hatrurim Formation (Dead Sea area). Doklady Earth Sciences, 2007, Vol. 413A, No. 3, pp. 474-480. Pleidades Publishing Ltd. English Text Version. Original Russian text in Doklady Akademii Nauk, 2007, Vol. 413, No. 6, pp. 803-809.


Stephens, J. 1762. An account of an uncommon phoenomenon in Dorsetshire: In a letter from John Stephens, M.A. to Emanuel Mendes da Costa, F.R.S. Philosophical Transactions of the Royal Society, London. vol. 53, p. 119. Reproduced in GCG Newsletter, 1 (9), 450-451. [Burning cliff near Charmouth].


Strahan , A. 1898. The Geology of the Isle of Purbeck and Weymouth. Memoirs of the Geological Survey. Her Majesty's Stationery Office, London. 278 pages with a map.
Vapnik, Y., Sokol, E., Murashko, M. and Sharygin, V. 200?. by Yevgeny Vapnik, Ella Sokol, Michail Murashko and Victor Sahrygin. [about 2006 or 2007, journal not known] Pp. 69-77. With colour photographs and an extensive list of minerals. [See also Sokol, E.V., Novikov, I.S., Vapnik, Y and Sharygin, V.V. 2007 (presented 2006). Gas fire from mud volcanoes as a trigger for the appearance of high-temperature pyrometamorphic rocks of the Hatrurim Formation (Dead Sea area). Doklady Earth Sciences, 2007, Vol. 413A, No. 3, pp. 474-480. Pleidades Publishing Ltd. English Text Version. Original Russian text in Doklady Akademii Nauk, 2007, Vol. 413, No. 6, pp. 803-809.]
[Example extract from the introduction]
"In Israel and Jordan there are more than ten areas totaling about 250 km2 with curious mineral and rock associations, known as the Hatrurim Formation (Fm). The genesis of these rocks is still problematic. Carbonate sedimentary rocks of late Cretaceous age (75-55 Ma) were subjected to local super-high temperature metamorphism (as high as 800- 1200C) beginning in the Miocene (especially in the range 16 Ma to 200,000 a). The thermal alteration is of the type referred to as combustion metamorphism. It is not likely an accident of nature that all these combustion complexes are located mainly in the vicinity of the Dead Sea Rift, the major structure of the region which has influenced the geological evolution of the region throughout the Cenozoic (Figs. 1 and 2). The Hatrurim Fm is best exposed in the Negev Desert, not far from the town of Arad. Hatrurim Basin, an area of about 50 km2, is located here (Fig. 2)......
And as a giant natural theatre the smoky Jordan shore ofthe Rift rises up a full 1 km (Fig. I). This is the Hatrurim Basin nestled it the Negev Desert. The striking appearance of these rocks and the rich range of tones - straw, terracotta, pink and olive - in the natural palette of the terrain are in fetching harmony with the relief of the Negev Desert. One should keep in mind that the Hatrurim Fm differs drastically from adjacent areas of unaltered sedimentary rocks by their monolithic appearance, rocky ledges, in some cases circular agglomeratic collars and surrounding them collars of the porous zeolitic rocks included in and located between brecciated and hydrothermally altered sedimentary rocks. So, it is not surprising that people living here in biblical times were imbued with awe by their natural surroundings. One senses that on a visit to the remarkable archeological complex of Hyrcania, the fortress of which was already known in 76-67 BC. A striking feature of the remnant walls of the monastery are blocks of metamorphic rocks. Similarly, brightly colored mosaic floors are composed of small bricks of the metamorphic rocks. The natural harmony of colors is still clear to see (Fig. 4). Up to the 1980's the rocks of Hatrurim Fm, or Arad stone, were excavated and used as decorative tiles..." [continues, and includes a surprisingly large mineral list].


Woodward , H.B. 1893. The Jurassic Rocks of Britain, vol. 3, The Lias of England and Wales (Yorkshire excepted). Memoirs of the Geological Survey of Great Britain.

Woodward, H.B. 1908. Burning cliffs. Geological Magazine, p. 561.

Woodward, H.B. 1911. The Geology of the Country around Sidmouth and Lyme Regis. Memoir of the Geological Survey of England and Wales. (see p. 86)

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Other Kimmeridge Field Guides

Kimmeridge, - Introduction
Kimmeridge - Fossils
Kimmeridge - Kimmeridge Bay
Kimmeridge - West of Kimmeridge Bay
Kimmeridge - East - Hen Cliff, Yellow Ledge and Cuddle
Kimmeridge - Blackstone, Oil Shale at Clavell's Hard
Kimmeridge - Burning Beach, Burning Cliffs
Kimmeridge - Rope Lake Head to Freshwater Steps
Kimmeridge - Freshwater Steps to Chapmans Poole
Kimmeridge - Bibliography - Start
Kimmeridge - Bibliography Continued

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Copyright © 2014 Ian West, Catherine West, Tonya Loades and Joanna Bentley. All rights reserved. This is a purely academic website and images and text may not be copied for publication or for use on other webpages or for any commercial activity. A reasonable number of images and some text may be used for non-commercial academic purposes, including field trip handouts, lectures, student projects, dissertations etc, providing source is acknowledged. No permission can be given for reproduction of any images of the Lulworth Cove area in books or in other websites, for special reasons.

Disclaimer: Geological fieldwork involves some level of risk, which can be reduced by knowledge, experience and appropriate safety precautions. Persons undertaking field work should assess the risk, as far as possible, in accordance with weather, conditions on the day and the type of persons involved. In providing field guides on the Internet no person is advised here to undertake geological field work in any way that might involve them in unreasonable risk from cliffs, ledges, rocks, sea or other causes. Not all places need be visited and the descriptions and photographs here can be used as an alternative to visiting. Individuals and leaders should take appropriate safety precautions, and in bad conditions be prepared to cancell part or all of the field trip if necessary. Permission should be sought for entry into private land and no damage should take place. Attention should be paid to weather warnings, local warnings and danger signs. No liability for death, injury, damage to, or loss of property in connection with a field trip is accepted by providing these websites of geological information. Discussion of geological and geomorphological features, coast erosion, coastal retreat, storm surges etc are given here for academic and educational purposes only. They are not intended for assessment of risk to property or to life. No liability is accepted if this website is used beyond its academic purposes in attempting to determine measures of risk to life or property.

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Dr Ian West, author of these webpages

Webpage - written and produced by:

Ian West, M.Sc. Ph.D. F.G.S.


at his private address, Romsey, Hampshire, kindly supported by southampton University,and web-hosted by courtesy of iSolutions of southampton University. The website does not necessarily represent the views of southampton University. The website is written privately from home in Romsey, unfunded and with no staff other than the author, but generously and freely published by southampton University. Field trips shown in photographs do not necessarily have any connection with southampton University and may have been private or have been run by various organisations.