Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Cold stage formation of calcrete nodules in the Chinese Loess Plateau: evidence from U-series dating and stable isotope analysis. .
AU - Rowe, P. J.
AU - Maher, B. A.
PY - 2000/3/15
Y1 - 2000/3/15
N2 - This pilot study shows that some calcrete nodules from the base of palaeosols in the Chinese loess sequences can be dated by U-series isochron methods. The ages obtained suggest that the nodules did not form during interglacial climate stages; rather, they formed either during interglacial/glacial transitions or glacial climate stages. Thus, the nodules appear not to have formed contemporaneously with the soils beneath which they immediately lie but significantly post-date them. Post-pedogenic injection of carbonate into stratigraphically lower horizons is therefore identified. This finding contradicts previous assumptions regarding the timing of nodule formation. Carbon and oxygen isotope analyses of the nodules identify isotopic compositions which independently suggest that climatic conditions cooler and possibly drier than at present prevailed at the time of nodule formation.
AB - This pilot study shows that some calcrete nodules from the base of palaeosols in the Chinese loess sequences can be dated by U-series isochron methods. The ages obtained suggest that the nodules did not form during interglacial climate stages; rather, they formed either during interglacial/glacial transitions or glacial climate stages. Thus, the nodules appear not to have formed contemporaneously with the soils beneath which they immediately lie but significantly post-date them. Post-pedogenic injection of carbonate into stratigraphically lower horizons is therefore identified. This finding contradicts previous assumptions regarding the timing of nodule formation. Carbon and oxygen isotope analyses of the nodules identify isotopic compositions which independently suggest that climatic conditions cooler and possibly drier than at present prevailed at the time of nodule formation.
KW - calcrete nodules
KW - Chinese loess
KW - palaeosol
KW - stable isotopes
KW - uranium series dating
U2 - 10.1016/S0031-0182(99)00157-1
DO - 10.1016/S0031-0182(99)00157-1
M3 - Journal article
VL - 157
SP - 109
EP - 125
JO - Palaeogeography, Palaeoclimatology, Palaeoecology
JF - Palaeogeography, Palaeoclimatology, Palaeoecology
SN - 0031-0182
IS - 1-2
ER -