SMALL SAMPLE DATING IN CHINA

The Xi'an Laboratory of Loess and Quaternary Geology has developed a s mall sample C-14 dating facility consisting of a Wallac 1220 Quantulus (TM) liquid scintillation spectrometer, and a miniature benzene synthe sis line based on the synthesis procedures used at the Australian Nati onal University (ANU). This line can produce ca. 0.3-ml benzene sample s, which are then measured for C-14 activity using 0.3-ml Teflon vials developed by Wallac Oy. The counting performance of the Quantulus(TM) spectrometer using 0.3-ml vials has been evaluated, and a potential a ge limit of ca. 45,000 BP has been obtained for samples containing up to 250 mg carbon. This dating facility fills the gap between large sam ple (2.4-6 g carbon) and microsample (<1 mg carbon) handling to form a C-14 dating method sequence.