The palynological and sedimentological research in the arid and semi-arid zone is generally limited to large lakes, often several hundred or thousand square kilometres in extent. The small lakes do not seem to attract as much interest. Although they are likely to possess a better spatial and temporal resolution of record than the larger lakes, they remain unstudied.
Following a preliminary sampling and survey of lakes in the Paroo region (far north-western NSW) a small ephemeral lake, named Palaeolake, was selected for study of its potential for Quaternary studies and possible reconstruction of past environmental and climatic conditions. Considering its location, some gaps in the record were expected. To increase the interpretational potential of the lake sediment data, multi-disciplinary analysis have been undertaken. They involved palynological studies as well as geomorphological and sedimentological analysis. Surrounding dunes have been cored in search of signs of sediment deflation from the lake basin (to estimate the possible extent of the incompleteness of the sediment data). Both dune and lake sediments have been processed for particle size distribution, mineral magnetic susceptibility, percentage organic matter content, pH, salinity, gypsum, caesium-137 content, mineral composition (XRD) and zooplankton content. Complementary SEM and EDS was done on selected particles. Soil samples were analysed for modern pollen representations.
An AMS radiocarbon date for 14,400 ± 150 years BP has been obtained for a depth equivalent to 80-85 cm in the lake sediments, while a sample from 180-190 cm depth had insufficient carbon to be dated using AMS.
Based on the multiple results, four distinctive stages in the Palaeolake environmental history have been identified: a large/deep lake stage, a drying lake stage, a fluctuating lake water stage, and a recent ephemeral lake stage. These stages seem to agree generally with similar events recorded in other arid and semi-arid zone lakes, such as Lake Eyre, Lake Tyrell, and Willandra Lakes.