摘要
ary name="EnDivSummary">Recently the successful application of laser heating 40Ar/39Ar dating to supergene alunite-group minerals demonstrates the applicability of the method to dating minerals existing in the oxidation zones of sulfur rich ore deposits. Laser-heating 40Ar/39Ar method not only reduces the amount of samples,but also the system background level; In addition,40Ar/39Ar step-heating dating method can test for the presence of hypogene contaminants,the excess/inherited Ar,and the multiple generations of supergene minerals. Although problems remain in isotopic dating of supergene alunite-group minerals,the systematic sampling and reasonable analysis process,combined with a variety of detection methods,can yield meaningful weathering ages,which will provide a new approach for the research on the timing of continental weathering,the formation of oxidization zones,and climatic desiccation of Northwest China.
