Late Quaternary ostracods from Lake George, New South Wales

Australia: The Land Where Time Began

Late Quaternary ostracods from Lake George, New South Wales see Lake George

Core LG4 from Lake George, the uppermost 3 m of which is believed to represent the last 60,000 years of sediment deposition in the lake contains fossil ostracods that are related to living ostracods (Singh et al., 1981b) as well as the history of the lake that was traced by current knowledge of ostracod ecology.

The author¹ has proposed the timing of a number of distinct phases at Lake George, though he warns against regarding them without caution, as there were not many ¹⁴C dates available.

Water fresh, lake full 20,700-19,100, 12,000-10,200 BP
Water fresh, ephemeral at times, 27,600-23,800, 23,500-23,700, 13,500-12,000, 10,200-8,500, 7,500, 7,000 BP, and at some stage between 60,000-27,000 BP.
Saline water, ephemeral, few short periods 27,600-23,800, 17,400-15,600, 4,000-3,200 BP
Definitely dry 19,100-17,400 BP

It has been found that the fluctuations of the level based on studies of ancient shore lines (Coventry, 1976) of the lake correlate reasonable well with and other studies based on analyses of facies and the plant microfossil record (Singh et al., 1981b).

In the core LG4 from Lake George, New South Wales, ostracods were extracted from the upper 3 m that represented faunas that lived in the last 60,000 years. The aim of the study was to determine the species distribution in the lake over time and use the known ecology of present day species, and by reference to them, reconstruct the history of the lake. They also searched for evidence that would indicate if ostracods were readily preserved in sediments of a large drainage basin that was known to dry up periodically and undergo pedogenic processes (Singh et al., 1981b). The authors¹ presented the comparison of data of the ostracods and the associated aquatic vegetation in an attempt to asses the type of information the study of the ostracods might be expected to provide, as the pollen and spore sequences from an adjacent core is known.

See Source 6 for systematic and ecology

Sources & Further reading