Publication Date:
2024-05-31
Description:
We present 22 U-series ages for a stalagmite from north-western Cuba based on multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and thermal ionisation mass spectrometry (TIMS). Our results reveal that the stalagmite continuously grew within the last ~1400a. Low uranium content of the sample and thus, extremely low 230Th concentrations limit the precision and accuracy of 230Th/U-dating by TIMS. Samples measured by MC-ICPMS show a high variability of 232Th content along the growth axis with some sections significantly affected by initial 230Th from a detrital phase. An a-priori bulk earth ratio for (238U/232Th) cannot be used to accurately account for this initial 230Th. Using an age model based on the 230Th/U ages determined on samples with low or negligible 232Th concentration, we find that the (238U/232Th) activity ratio of the detrital phase is an order of magnitude larger than the bulk earth value, indicating the importance of an accurately determined correction factor.
Keywords:
Age, comment; Age, dated; Age, dated standard deviation; CG; Cuba_Grande; DISTANCE; Integrierte Analyse zwischeneiszeitlicher Klimadynamik; INTERDYNAMIK; Multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS); Pinar del Rio (NW Cuba); Speleothem sample; SPS; Thorium-230/Thorium-232 activity ratio; Thorium-230/Thorium-232 activity ratio, standard deviation; Thorium-230/Uranium-238 activity ratio, standard deviation; Thorium-230/Uranium-238 ratio; Thorium-232; Thorium-232, standard deviation; Uranium-234, standard deviation; Uranium-234/Uranium-238 activity ratio; Uranium-238; Uranium-238, standard deviation
Type:
Dataset
Format:
text/tab-separated-values, 351 data points
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