Dating of speleothems
A correlation between soda straw U-series ages and radiocarbon ages of charcoal from the site is shown.Multiple soda straw age determinations for a single stratigraphic unit are required in order to verify age concordance.
Thick glaciers, far larger than those that currently cap the mountain peaks, covered the Alps.In contrast to other speleothem formations, soda straw stalactites are fragile, have typically short life spans (usually only years but rarely up to a few hundred years) and are frequently incorporated into cave deposits.Results of thermal ionisation mass spectrometry (TIMS) U-series dating of soda straw stalactites from palaeontological excavations at Blanche Cave, South Australia, show that small, dense, clean straws tend to yield ages closest to the time of stratigraphic deposition.In conjunction with other dating methods, U-series dating of soda straw stalactites may help to significantly constrain the age of stratigraphic units and associated archaeological and palaeontological deposits in order to provide more robust chronologies.Here we advocate the collection of soda straw stalactites at future excavations of limestone cave sites.by Holli Riebeek · design by Robert Simmon · June 28, 2005 The first pieces of evidence for climate change came from the land itself, from the misplaced boulders scattered across much of the Northern Hemisphere, though there were other signs as well.
A homogeneous, fine yellow soil covered more than one million square miles of Europe, Asia, and North America.
Less well known, water deposits can also dry in a flat slab called a flowstone.
Geologists refer to the mineral formations in caves as “speleothems.” While the water flows, the speleothems grow in thin, shiny layers.
Uranium-series (U-series) dating of speleothems is frequently used for palaeoclimate studies but its archaeological and palaeontological applications are limited to stratigraphically significant speleothem formations, such as flowstones, to provide maximum and minimum temporal points.
This study targeted soda straw stalactites for U-series dating.
This is consistent with observations from several other caves and suggests that conditions generally were unfavorable for speleothem formation during glacial periods.