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For as long as anyone can remember Mt Wingen has been burning, with an acrid smell of sulphur in the fumes issuing from cracks along its summit. Australia’s Aboriginal inhabitants had known about this burning mountain for many years before the European settlers reached the area, but soon after they came this spectacle attracted scientific attention. The earliest European visitors to describe the phenomenon, Reverend C.P.N. Wilton (between 1828 and 1832) and Sir Thomas Mitchell (in 1829 and 1831), correctly recognized its cause, although this burning mountain became widely known overseas at that time as a volcano or pseudo-volcano.1

Burning coal

Burning Mountain is located five kilometres (about 3 miles) north of the village of Wingen on a major highway between Brisbane and Sydney. Sydney is about 200 kilometres (125 miles) to the south. But Burning Mountain is not a volcano, Australia being fortunate in not having any volcanoes still active today. Instead, within Mt Wingen is a layer of coal that is burning, having been set alight by natural means.

The coal layer (or seam) and associated sandstone, shale and claystone layers at Mt Wingen are called the Koogah Formation, and assigned an Early Permian ‘age’ according to evolutionary terminology.2 Below the Koogah Formation are the thick lavas of the Werrie Basalt, which is also assigned an Early Permian evolutionary ‘age’. Overlying the Koogah Formation are alternating layers of conglomeratic mudstones and sandstones containing fossilized shellfish (brachiopods and pelecypods), together called the Bickham Formation. These geological relationships can be seen easily in the geological cross-section of Figure 1, which depicts these rock units as they are seen where a west-flowing creek transects the Mt Wingen ridge 1.5 kilometres (less than a mile) north of Burning Mountain.3

Subsidence and fused rocks

The ‘burnt-out’ zone extends north-easterly for at least 6.5 kilometres (4 miles) from the present zone of burning at Burning Mountain. The land surface above the ‘burnt-out’ zone is characterized by subsidence features such as fractures, closely-spaced parallel faulting, small grabens (fault-bounded gullies) and open gash-like fissures, which appear to have been controlled by the jointing system in the rocks of the Koogah Formation.4

Small, collapsed, chaotically broken areas containing highly altered and fused rocks may represent ‘chimneys’ through which high-temperature burning gases escaped (see Figure 1 again). Fused sandstones associated with these ‘chimneys’ contain rare high-temperature forms of the common mineral quartz and another high-temperature mineral in a rock glass of slaggy, vesicular (bubbly) appearance.

Elsewhere in the ‘burnt-out’ area the highly refractory (high-temperature) kaolinite-bearing claystones, which originally were underneath the unburnt coal layer, have been relatively little affected by the burning of the coal (see Figure 2). A thin zone of the claystone just below the burnt coal layer (see Figure 2 again) has been converted to the mineral mullite, a very common refractory form of aluminium silicate.5 However, the kaolinite-bearing claystone above the burnt coal layer, which was subject to the full effects of burning gases, has been more extensively altered to the high-temperature forms of quartz and aluminium silicate (including mullite).

A blast-furnace effect

Experimental work, including laboratory ‘firing’ and fusion tests on the ‘natural starting materials’ suggests that temperatures of up to 1700°C must have been attained in the burning zones in order to account for these and other alteration effects due to thermal metamorphism.6, 7

As a consequence of the burning of the coal layer a variety of thermal and chemical replacement effects and mineralogical phenomena occur, as has already been described above.

The area on Burning Mountain which is presently burning is a highly fissured zone heated to red-white heat over an area of less than 100 square metres.8, 9 Intake of air through the fissures appears to have resulted in a blast-furnace effect being added to the natural combustion of the coal and its gases 30 metres (almost 100 feet) below the surface. Fissures are continuing to open in as yet unburnt ground immediately south of the present area of thermal activity as underground collapse occurs.

Heated aqueous fumes emanating from the burning area deposit a sinter composed of hematite (an iron oxide) and high-temperature forms of quartz, encrusted with elemental sulphur which has come from the sulphide minerals, chiefly pyrite (iron sulphide), found in the coal. It is for this reason that the fumes have a pungent sulphur smell, while condensate from these fumes is highly acidic and strongly sulphatic.10

For many years these open fissures in the ‘vent’ area were used to extract water and gases for the production of a liquid and an ointment with supposed medicinal value.11 These products were sold until the 1960s. The visitor in those days would have been confronted with an array of various pipes and ducts over the fissures.

How did the fire start?

But how did this coal seam get ignited and for how long has it been burning? It has been estimated that the burning front has been moving southward at a rate of approximately one metre (more than 3 feet) every year and has moved about 6,000 metres (nearly 4 miles) to its present position.12 Thus, if the coal has burned in the past at the current rate, then the fire started probably at most about 6,000 years ago. Even allowing for variations in the rate, the evidence certainly indicates that it has been burning for a few thousand years, not millions.

Those prepared to hazard a guess have suggested that the coal seam may have been ignited naturally through a lightning strike, a forest fire, or more probably through spontaneous combustion, the latter phenomenon being known to occasionally occur in coal mines today.13

However, spontaneous combustion of coal seams today is not known to occur where a coal seam is weathering in outcrop at the surface. On the contrary, spontaneous combustion occurs where coal has been freshly exposed in mine workings, whether in an open pit or in underground tunnels, the heat which ignites the coal being generated by a rapid drying out and oxidation of the coal constituents because they have been rapidly exposed to the elements by the mining process.

figure 1
Figure 1

Cross section through Mt Wingen, 1.5km north of the present burning zone, showing the geological strata in the mountain particularly the burning coal layer (seam) (after Rattigan).

As for the other suggested mechanisms for igniting the coal, namely, a lightning strike or a forest fire, again simple reasoning exposes the improbability of these explanations. To begin with, any coal exposed at the land surface as outcrop would be highly weathered due to the way coal rapidly oxidizes and weathers when exposed to the elements at the earth’s surface. It is not that a lightning strike or a forest fire could not ignite an outcropping coal seam, but the weathered nature of the exposed coal would make ignition more difficult.

But that is not the only problem. Once ignited at the surface the fire has to burn along the coal seam under the ground, having first to pass through the water table. There the seam would be saturated with water, so the fire would almost certainly be extinguished.

Added to that, as any fire moved along a coal seam down under the ground the supply of oxygen necessary for the burning process would continually decrease. Admittedly, if the fire became established under the ground, the rocks above the burnt-out coal would tend to fracture and collapse, thus allowing air down into the burning zone, as appears to be the case on Burning Mountain. But to achieve that situation any fire ignited at the surface has to overcome the other hurdles of passing through the weathered zone and the water table with a diminishing air supply initially.

A volcanic intrusion?

figure 2
Figure 2

The burning area today on top of Mt Wingen. There is ‘smoke’ coming out of the ground and the surrounding white sinter.

So if these explanations for the igniting of this underground coal fire beneath Burning Mountain are either tenuous or virtually impossible, how are we to explain this phenomenon? There is one other explanation that has been hinted at subtly in one of the few scientific papers written about this site, but herein lies the challenge for uniformitarian/evolutionary geologists and their millions-of-years timescale.

One geologist, a staff member at the time at the University of Newcastle (New South Wales), observed where previously molten volcanic rock has cut through the coal seam at some time in the past and cooled (Figure 2).14, 15 Now it is well known that such molten rock can be intruded at temperatures around 1000°C causing thermal metamorphic effects in the rocks it intrudes, while the intense heat radiates outwards from the molten rock as it cools over subsequent weeks and months. In other places, such molten rock intrusions through coal seams have been known to have either severely metamorphosed the coal or ignited it.

This then is the most likely mechanism for the igniting of the burning coal under Mt Wingen. Furthermore, since this appears to have happened less than 6,000 years ago, this intrusion would have been sufficiently close to the surface for fractures to supply the necessary air to the ignited coal to keep it burning.

Evolutionary time challenged

So when was the last volcanic activity in this area according to the evolutionary timescale? This molten rock which cross-cuts the coal seam could hardly have come from the same volcano that poured out the basalts of the Werrie Basalt, because those basalts underlie the coal seam of the Koogah Formation and are thus much older than this intrusive volcanic rock (in evolutionary geologic terms). Besides, the Werrie Basalt is said to be of ‘Permian’ age, that is, supposedly over 260 million years old.16, 17

The closest volcanic activity to Mt Wingen that occurred after formation of the coal seam is that responsible for the Liverpool Range Basalts, less than 5 kilometres (3 miles) to the north and to the west18 The same basalts are found to the north-east of Mt Wingen also. But these basalts have been dated using the potassium-argon radioactive method as 38 million to 41 million years old.19 Today they cover an area of approximately 6000 square kilometres (almost 2,620 square miles) and are in places up to 800 metres (over 2,600 feet) thick, so they represent an enormous outpouring of molten lavas.20 Thus it seems likely that these small intrusions of similar composition in the nearby Mt Wingen area are related to the same volcano and volcanic event. Indeed, there are intrusive rocks of related composition and the same ‘age’ about 80 kilometres (49.5 miles) to the south,21 and other intrusives about 20 kilometres (12.5 miles)22 and 50 kilometres (31 miles)23, 24 to the south, so volcanic activity has been widespread through this region.

However, this would imply that if this intrusive rock at Burning Mountain is supposedly 38 million to 41 million years old, then it must have ignited the coal seam at that time. This is clearly impossible, for we have seen that observational evidence in the present is only consistent with the coal having been burning for less than 6000 years. Consequently, if this intrusive rock ignited the coal then it can’t be millions of years old.

Is it any wonder then that Burning Mountain is a challenge to the evolutionary timescale, a challenge which is ignored by geologists generally? Because of the bias generated by their evolutionary indoctrination, they cannot allow evidence like this to challenge their time framework. On the other hand, the evidence is totally consistent with residual volcanic activity sometime after the Flood having ignited this coal seam under Burning Mountain only thousands of years ago.

References

  1. Valiance, T.G., 1975. Presidential address: Origins of Australian geology. Proceedings of the Linnean Society of New South Wales, vol. 100(1) pp. 13–43.
  2. Percival, I.G., 1985. Site 31. Mt Wingen (Burning Mountain). In: The Geological Heritage of New South Wales, Volume 1, New South Wales National Parks and Wildlife Service, Sydney, pp. 94–95.
  3. Rattigan, J.H., 1967. Phenomena about Burning Mountain, Wingen, New South Wales. Australian Journal of Science, vol. 30(5), pp. 183–184.
  4. Percival, Ref. 2.
  5. Rattigan, Ref. 3.
  6. Rattigan, Ref. 3.
  7. Rattigan, J.H., 1967. Occurrence and genesis of halloysite, Upper Hunter Valley, New South Wales, Australia. American Mineralogist, vol. 52, pp. 1795–1805.
  8. Rattigan, Ref. 3.
  9. Percival, Ref. 2.
  10. Rattigan, Ref. 7.
  11. New South Wales National Parks and Wildlife Service, 1986. Burning Mountain Nature Reserve: Walking Track Guide.
  12. New South Wales National Parks and Wildlife Service, Ref. 11.
  13. New South Wales National Parks and Wildlife Service, Ref. 11.
  14. Rattigan, Ref. 7.
  15. Loughnan, F.C. and Craig, D.C., 1950. An occurrence of fully hydrated halloysite. American Mineralogist, vol. 45, pp. 783–790.
  16. Rattigan, Ref. 3.
  17. Rattigan, Ref. 7.
  18. Schön, R.W., 1985. Petrology of the Liverpool Range Volcanics, eastern New South Wales. In: Volcanism in Eastern Australia, F.L. Sutherland, B.J. Franklin and A.E. Waltho (Eds), Publications of the Geological Society of Australia, NSW Division, vol. 1, pp. 73–85.
  19. Wellman, P. and McDougall, I., 1974. Cainozoic igneous activity in eastern Australia. Tectonophysics, vol. 23, pp. 49–65.
  20. Schön, Ref. 18.
  21. Schön, Ref. 18.
  22. Martin, R.W., 1985. A small layered tholeiitic intrusion emplaced at shallow level, at Scone, New South Wales. In: Volcanism in Eastern Australia, F.L. Sutherland, B.J. Franklin and A.E. Waltho (Eds), Publications of the Geological Society of Australia, NSW Division, vol. 1, pp. 107–140.
  23. Rattigan, Ref. 7.
  24. Rattigan, Ref. 15.