Site occupation spans at Middle Ceramic Antelope Creek phase sites in the Southern Plains of Texas

Twenty-one AMS radiocarbon and optical stimulated luminescence assays from Early Ceramic (Plains Woodland) and Middle Ceramic (Antelope Creek) periods are reported from sites on the Cross Bar Ranch in Potter County, Texas including the first direct date on Phaseolus sp. remains in the Southern Plains. Calibrated radiocarbon dates and a single luminescence assay are used to evaluate site occupation spans during the Middle Ceramic Antelope Creek phase (ca. AD 1150–1450). A method for determining occupation sequences between sites using combined probabilities is presented for Antelope Creek occupations on the Cross Bar Ranch and the entire period of occupation at the Cross Bar Ranch is compared to other direct dates on cultigens from the greater Antelope Creek phase in the Southern Plains of Texas.本文报道了采自美国得克萨斯州波特县克罗斯巴尔牧场遗址的21例AMS放射性碳（AMS radiocarbon）与光激发释光（optical stimulated luminescence）测年分析数据，样品年代覆盖早期陶期（平原林地文化期，Plains Woodland）与中期陶期（羚羊溪文化期，Antelope Creek），其中首次获得了南部大平原地区菜豆属（Phaseolus sp.）遗存的直接测年结果。研究采用校正放射性碳测年（Calibrated radiocarbon dates）结果与1例光释光测年数据，对中期陶期羚羊溪文化期（约公元1150–1450年）的遗址占据时段进行了评估。本文提出了一种基于联合概率（combined probabilities）法确定遗址间占据序列的方法，以克罗斯巴尔牧场的羚羊溪文化期遗存为研究案例，并将该牧场的完整占据时段与得克萨斯州南部大平原地区大羚羊溪文化期内的栽培作物直接测年数据进行了对比。