Collaborative Research: Testing the Reliability of Paleo Ventilation Estimates

合作研究：测试古通风估计的可靠性

• 批准号: 1029936
• 负责人: Jerry McManus
• 金额: $ 22.7万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1029936&HistoricalAwards=false
• 关键词: Collaborative; Research; Testing; Reliability; Paleo

The PIs' preliminary data from sediment cores from deep equatorial Pacific show evidence of old radiocarbon ages and thus the presence of old, poorly ventilated bottom water brought to the surface as deglaciation began at the end of the last glacial, thereby potentially explaining the prolonged decrease in radiocarbon content and a concurrent increase pCO2 levels of the atmosphere. The PIs propose to evaluate this ventilation signal further and test its significance through a combination of 14C and 230Th measurements on selected additional cores in order to better understand the effects of benthic processes. In addition, Thorium profiling will be used to test the significance of maxima in foraminiferal abundance that are dated with 14-C. This method will be used to evaluate the accumulation rates of benthic foraminifera and the possible role of winnowing and sediment focusing in creating benthic abundance peaks. Thorium data will also help refine chronology of millennial-scale events in the eastern Equatorial Pacific over the last 25 K.Y.Broader Impacts: The scientific impact of the findings could be strong for other paleoclimate research. Outreach and educational efforts include training of teachers, students and a post-doctoral researcher.

来自深赤道太平洋沉积物核心的PIS的初步数据显示了旧的放射性碳年龄的证据，因此，随着脱胶的结束，在最后一次冰川结束时，旧的，通风不良的底部水带到了表面，从而可能解释了延长的延长降低。在放射性碳含量和同时增加大气的PCO2水平。 PI提议进一步评估该通风信号，并通过对选定的其他核心进行14C和第230个测量的结合来测试其显着性，以便更好地了解底栖过程的影响。 此外，thor谱分析将用于测试最大值在14-C的有孔虫丰度中的重要性。该方法将用于评估底栖有孔虫的累积速率，以及重点和沉积物在创建底栖丰度峰方面的可能作用。 Thor Data还将有助于在过去25个K.Y. BROADER的影响下，在东部赤道太平洋地区的千禧年级事件的年表：研究结果对其他古气候研究的科学影响可能很大。外展和教育工作包括对教师，学生和博士后研究人员的培训。