Radioanalytical techniques for quaternary dating

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The global long-term goals of this research program are: (1) to develop new radiochemical analytical techniques and (2) to apply improved radiometric techniques for dating environmental samples from the Quaternary. The determination of the age of environmental samples is not simple when events are older than recorded history; yet it is fundamental to many aspects of environmental science. Historical chronologies of many environmental processes can be developed by aging samples. For example, atmospheric and groundwater transport, as well as rock and sediment ages, interpreted using geochemical theories, can be used to reconstruct temporal trends, to determine rates of environmental change, and to test models of environmental processes. Radiometric dates can be obtained using either the radioactive decay of a nucleus or the rate of production of a given isotope by a nuclear reaction that occurs at a constant and known rate. The dating of many young Quaternary samples has proven difficult because high precision measurements on closed systems are not possible. In older systems, accurate dates often prove difficult because most 14C has already decayed or the initial activity is uncertain, and other techniques often violate the requirements of a closed system. This research will provide new ways to measure radionuclides and more robust dating techniques for Quaternary materials covering a wide range of ages. These techniques will be used to in environmental assessments, climate change studies, ecological impact statements and other applications where it is important to look at the longer term behaviour of a system and the impact of human and natural events on that system.