EXAMINATION OF BULK SOIL AND AMS RADIOCARBON AGE DETERMINATION OF MATERIAL FROM A PALEOSEISMIC TRENCH AT THE FILOLI SITE, SAN MATEO COUNTY, CALIFORNIA

Eleven bulk soil samples from a paleoseismic trench across the San Andreas Fault at the Filoli site in San Mateo County, California, were floated to recover organic fragments suitable for radiocarbon age determination. These samples were collected from the south and north walls of the trench and range in depth between 0.2–2.5 m below ground surface. Botanic components were identified and potentially radiocarbon datable material was separated. Ten AMS radiocarbon dates were obtained on charcoal and charred botanics from eight samples.

采自美国加利福尼亚州圣马特奥县菲洛利（Filoli）遗址处横穿圣安德烈亚斯断层（San Andreas Fault）的古地震探槽的11件散装土壤样品，经浮选法处理以回收适用于放射性碳年代测定的有机碎屑。该批样品采集自探槽的南、北两壁，埋藏深度介于地表以下0.2至2.5米之间。研究人员对样品中的植物组分完成鉴定，并分离出具备放射性碳测年潜力的物质。随后对其中8件样品中的木炭及炭化植物残体开展加速器质谱（AMS）放射性碳测年，共获取10组有效测年数据。