Rb sr dating heart dating uk
Three of the analyzed samples (H6, KQ1 and TZ67) generated Rb-Sr isochron ages of 141 ± 61 Ma, 332 ± 32 Ma and 235 ± 8 Ma (errors quoted at 2σ), respectively.
These results are similar to the corresponding K-Ar ages (125 Ma, 389 Ma and 234 Ma).
The red dashed line is regressed without subsample B-4; (C) KQ1.
The red dashed line is regressed without subsample C-5; (D) Q1.
The isotopic ages are consistent with the timing of hydrocarbon charge which varies in different drillholes as constrained by basin modelling, indicating that a closed-system behavior is attained by the hydrocarbon charge that inhibits the illitization of I/S.
The Rb-Sr isotope analyses of the other two samples (YM35-1 and Q1) that did not yield isochron ages suggest the conditions for producing isochrons were not satisfied, which may be caused by disturbance of the isotope system by a post-charge hydrothermal event.
Therefore, an isochron may be established for a single clay sample through Rb-Sr analysis of multiple extractions from the same sample (i.e.“subsamples”) without additional experimental leaching steps. The aim of this study is to illustrate the feasibility of this dating method through cross-checking against K-Ar ages for the samples initially reported in ref..Silurian bituminous sandstone (SBS) is a significant hydrocarbon reservoir in the Tarim Basin, northwest (NW) China.The black line in each diagram is the isochron regressed from data of all subsamples.The red dash line is the isochron regressed through selected data. The red dashed line is regressed without subsample A-3; (B) H6.