(Table 1) Age determination of sediment profile SO90-41KL/63KA

The 14C ages of planktonic foraminifers Globigerinoides sacculifer bracketing the Younger Dryas in a d18O record of Globigerinoides ruber from a laminated sediment core on the Pakistani continental margin suggest that surface reservoir ages in the Arabian Sea were in excess of 1000 years during the deglaciation. A least squares error fit of a detailed 14C chronology to the (atmospheric) tree ring record gave variable early Holocene reservoir ages between 780 and 1120 years, well above the prebomb value of 640 years. Mid-Holocene reservoir ages are less well constrained but were probably closer to the prebomb value. The method used to fit individual core sections to the tree ring record was designed to require only a rough a priori estimate of the time spans, which in the core presented here were taken from each section's range of 14C ages. A significant 220-year quasi-oscillation was present in the d18O record during the early Holocene but not thereafter. This frequency and amplitude pattern resembles an early Holocene 207- to 227-year oscillation previously observed in the atmospheric 14C record, which is generally interpreted as reflecting solar irradiance variability. An early Holocene climate event at 8150-8400 calendar years B.P. observed elsewhere within the Asian-East African monsoon system was again found in our record, suggesting a reduction in precipitation over NW India and Pakistan.

对取自巴基斯坦大陆边缘的纹层沉积岩芯中红拟抱球虫（Globigerinoides ruber）的δ¹⁸O记录里，夹在新仙女木事件（Younger Dryas）前后的泡抱球虫（Globigerinoides sacculifer）浮游有孔虫（planktonic foraminifers）的¹⁴C年龄结果显示：冰消期（deglaciation）阿拉伯海的表层海水储库年龄（reservoir ages）超过1000年。将高精度¹⁴C年代序列与大气树轮记录进行最小二乘误差拟合（least squares error fit）后，得到早全新世（Holocene）的储库年龄介于780至1120年之间，远高于640年的核爆前基准值（prebomb value）。中全新世的储库年龄约束精度较低，但推测其数值更接近核爆前基准值。本研究用于将单个岩芯段匹配至树轮记录的方法，仅需对时间跨度进行粗略的先验估计，本次研究岩芯的各段时间跨度取自其对应的¹⁴C年龄范围。早全新世的δ¹⁸O记录中存在显著的220年准振荡（quasi-oscillation），该特征在全新世晚期不复存在。该振荡的频率与振幅模式，与此前在大气¹⁴C记录中观测到的早全新世207至227年准振荡高度相似，这类振荡通常被解释为太阳辐照度变化（solar irradiance variability）的反映。本次记录中还重现了此前在亚洲-东非季风系统（Asian-East African monsoon system）其他区域观测到的、发生于8150至8400日历纪年距今年（calendar years B.P.）的早全新世气候事件，该事件指示印度西北部与巴基斯坦地区的降水有所减少。