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Creation 34(1):46–48, January 2012

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Caves and age

How radioactive dating confuses the situation


Caves layers

Caves are a common feature of karst landscapes—the rugged sort formed in rocks that dissolve easily such as limestone (mainly calcium carbonate), forming underground passages and drainages. Caves have always been considered the perfect archive, preserving the past, unlike most other environments. And they offer evolutionary scientists an array of items aching to be radiometrically dated.

These include the inspiring stone decorations called speleothems—such as stalactites (on the ceiling), stalagmites (on the floor) and flowstone. These formed when water enriched by dissolved carbon dioxide (CO2)—making it acidic—dissolved the alkaline calcium carbonate (CaCO3) in one place and released the mineral in another.1

Evolutionists claim speleothems formed over hundreds of thousands of years. But in my own evolutionary days, I had never considered an important consequence of such an age: the tiny water droplet, which built that stalagmite, had to keep arriving at precisely the same spot on the floor of the cave for 100,000 years!

Well, I knew—and all karstologists know—that the surface of limestone terrains above caves changes dramatically in short periods of time. And any change at the surface also changes the location of the water droplets inside the cave. However, the stalagmites do not indicate any changes. So the conclusion is simple: they cannot be that old. And that fact indicates the old-age belief is fallacious.

Radiometric dating

Speleothems are amenable to the uranium-thorium (234U/230Th) method of dating, and caves are assumed to be much less prone to variations of all sorts. Sometimes the ‘measured’ ages of speleothems can be tested by radiocarbon ages of artefacts and fossils found in caves. Speleothems are believed to preserve accurate records of ancient climates—or paleoclimates. This is because they preserve oxygen and carbon isotope ratios from the past, and that allows scientists to make paleoclimate reconstructions.

Radiometric dating however often disagrees with the observed growth rates of speleothems and their complex formation processes,2 and this confuses attempts to make sense of speleothem interpretations. As for paleoclimate reconstructions, one must understand well how any variation in climate could have affected the isotopic ratios and accurately relate these to the speleothem record.

Speleothems and ice cover

On the use of climate variations, karstological wisdom maintains that during the Ice Age the water infiltrating into caves either stopped or significantly diminished. At this time, ice covered much of the ground and even where it didn’t, beyond the ice sheets, permafrost was extensive. With less water it is expected that the growth of speleothems would be arrested or much diminished. This is a soundly-based understanding of how past environments would affect speleothem development.

Yet, this karstological wisdom is contradicted by most of the speleothems studied from areas that are known to have been affected by the ice cover! The reason is all to do with the dates that have been assigned by radioactive dating.

Because of the ‘dates’, evolutionists concluded that speleothems grew fast when they should not have grown, and did not grow when they should have! Rather than discard the dates, most evolutionary scientists prefer to discard all ‘unorthodox’ speleothems, and use only the few that match their grand scheme of things.

Vancouver Island karst

Some of the contradictory results have come from the karst on Vancouver Island, Canada, which has provided only a few datable speleothems. The reason for the paucity of specimens is that the island was covered by up to 2 km (6,500 ft) of ice during the Fraser Glaciation, the most intense episode of glaciation during the Ice Age. Understandably, the speleothems did not grow when ice covered the landscape, and after the ice melted, the caves are too young to have a large number of speleothems. In fact all North American karst terrains that have been covered by ice have similar characteristics.

Also, massive amounts of meltwater, running beneath the ice sheet, repeatedly flooded Vancouver Island caves. This is revealed by the frequent and large rounded boulders inside many caves, some transported by moving water from a considerable distance. This would have destroyed any speleothems and prevented new ones from forming. Thus, in North America, only caves south of the ice cover during the Ice Age are rich in speleothems.

The Vancouver Island speleothems have yielded radiometric ages of between 12 and 18 thousand years.3,4 That creates a problem and causes confusion. According to various geological evidences, the island was covered by ice, so the speleothems should not have grown at this time. But rather than question the radio-isotopic dates (and hence the methodology involved), some scientists have proposed that the 2-km—(6,500-ft—) thick ice cover melted and grew back in a few thousand years, even though there is no evidence for this melting and they cannot explain how it could have happened! Of course, a simpler explanation is that the radiometric dating is incorrect and that the speleothems grew only after the ice had melted.

Arch Cave

Another contradictory result was uncovered by scientists studying a speleothem from Arch Cave on Vancouver Island. They nonchalantly stated that the cave was “chosen for its proximity to the ocean so as to reflect a global climate history, and for its abundance of accessible cave deposits that were distant enough from the cave entrance and ground surface to mitigate any seasonal temperature effects.” In other words, they envisaged that speleothem growth on the ancient shore lines on the east coast of Vancouver Island would allow meaningful global correlation as the world’s sea level oscillated during the Ice Age—rising and falling as ice was locked on continents or melted.

Based on the measured oxygen and carbon isotopes (18O and 13C) they reconstructed the paleoclimate from the speleothem, which was radiometrically dated at 12,500 years. Yet, the geological evidence indicates the island was covered by ice at that time, so there should have been no speleothems growing at all. Not only the island, but the nearby Strait of Georgia was completely plugged by ice, with glacial scouring still visible on the bottom. In spite of this, maintaining their unshakable confidence in radiometric dating, the scientists conveniently ignored these geological facts and claimed the speleothems grew beneath the ice cover.

But if there really was this much ice cover at the time that the speleothems grew, the water infiltrating into the caves would not reflect the atmospheric composition at the time (as rainwater infiltrating into caves does today). Rather it would reflect an unreliable mixture of water from the melted ice layers. That would render any paleoclimate reconstruction from speleothems meaningless. Under such circumstances the ‘global climate history’ cannot be reconstructed and cannot be directly correlated with data from the caves.

In other words, by uncritically accepting the radioactive date without question, the researchers have ended up with a scheme that contradicts the geological evidence and undermines the basis for making paleoclimate reconstructions in the first place.

Clearing the confusion

On the other hand, when we apply some scientific skepticism to the spurious dates, we uncover a rather simple and consistent scenario that is in perfect accordance with the Genesis record. This allows us to understand the proper sequence of events, with the effects of Noah’s Flood being the key. The caves on Vancouver Island formed after the Flood and during the Ice Age.5 As creationist geologists have so simply documented, the Ice Age was a consequence of the warmer oceans and cooler land that existed on the earth immediately after the Flood.6 Only when the ice from the Ice Age had retreated did speleothems start growing inside those caves, and these have recorded the post-glacial climate variations over the last 4,000 years.

Posted on homepage: 29 July 2013

References and notes

  1. Lewis, D., Rapid stalactite growth in Siberia, Creation 32(1):40–42, 2009; creation.com/stalactite. Return to text.
  2. Silvestru, E., Caves for all seasons, Creation 25(3):44–49, 2003; creation.com/all-seasons. Return to text.
  3. Latham, A.G., Schwarcz, H.P. and Ford, D.C., Secular variation in the Earth’s magnetic field from 18.5 to 15.0 ka BP, as recorded in a Vancouver Island stalagmite, Canadian Journal of Earth Sciences 24:1235–1241, 1987. Return to text.
  4. Marshall, D., Bassam, G., Countess, R. and Gabities, J., Preliminary paleoclimate reconstruction based on a 12,500 year old speleothem from Vancouver Island, Canada: Stable isotopes and U–Th disequilibrium dating, Quaternary Science Reviews XXX:1–7, 2009. Return to text.
  5. Silvestru, E., Geology and Cave Formation: A Post-Flood Story, DVD. Return to text.
  6. Evolutionary ideas of the ice age involve cooling of the whole earth, but cold seas won’t evaporate much, hence fewer clouds, so less snow, so no source of the ice sheets. But the “fountains of the great deep” (Genesis 7:11) would have warmed the ocean, and cooled the land when volcanic ash blocked sunlight. See the Creation Answers Book, ch.16; creation.com/cab. For more technical detail, see Oard, M.J., An Ice Age Caused by the Genesis Flood, Institute for Creation Research, El Cajon, California, 1990. Return to text.