Speleothem dating sites
Speleothems are amenable to the uranium-thorium (Th) 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.
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.
C) they reconstructed the paleoclimate from the speleothem, which was radiometrically dated at 12,500 years.
Of course, a simpler explanation is that the radiometric dating is incorrect and that the speleothems grew only the ice had melted.
Another contradictory result was uncovered by scientists studying a speleothem from Arch Cave on Vancouver Island.
With less water it is expected that the growth of speleothems would be arrested or much diminished.
The reason is all to do with the dates that have been assigned by radioactive dating.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.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.