Characteristics of n-alkanes in tropical sediment – implications for palaeoenvironmental research

There are still significant knowledge gaps in our understanding of the Quaternary palaeo-history of tropical Australasia. Sedimentary archives, such as lake or cave sediments, and their associated proxies, have properties which can illuminate past climate and ecology, and provide insight into how people have interacted with their environment. Biomarkers such as n-alkanes are increasingly being used to study past vegetation assemblages as they have the potential to preserve well when compared to other widely used proxies such as pollen. In addition, as compound-specific isotopes can be measured on n-alkanes, there is great potential for investigating vegetation sources more directly than can be achieved when using isotopes measured on bulk organic material. n-Alkanes, which are hydrocarbons associated with plant leaf waxes, are the focus of the work presented in this thesis. While these biomarkers have been studied widely in the Northern Hemisphere, there is still a lack of palaeo-environmental research using n-alkanes and compound-specific isotopes in the Southern Hemisphere. Specifically, the work presented in this thesis will focus on n-alkanes in tropical Australasia, a region from which few palaeo-environmental records exist and which is a particularly challenging environment in which to preserve biomarkers and other bio-proxies. Thus, this PhD will provide additional and complementary environmental information to that provided by commonly used palaeo-environmental proxies such as pollen.