Study of the varve record from Erlongwan maar lake, NE China, over the last 13 ka BP

In a sediment sequence from Erlongwan maar lake that spans the last 13 ka BP, two main varve types can be recognized: biogenic varves (from the present to ~11.2 ka BP, 0―632 cm) and clastic varves (from ~11.2 to ~12.7 ka BP, 632―700 cm). Based on the dominant types of algae contained in the sediment, the biogenic varves can be classified into dinocyst-biogenic varves (0―63 cm) and mixed (dinocyst and diatom)-biogenic varves (214―632 cm). In this paper, the formation process and com- ponents of the varve are described, the possible reason for the types of varve changing throughout the record is discussed and a high-resolution varve chronology is established spanning the last 13 ka BP. Although further varve counting and error assessment are needed, the results presented here repre- sent a solid foundation for studying the palaeoclimate record of Erlongwan maar lake.

Study of the varve record from Erlongwan maar lake, NE China, over the last 13 ka BP