Pollen in seas near Nansha Islands mainly is from the local trilete spores.
Similar pollen characteristic is found when global warming occurs since 12 Ma.
Pollen on the coast of Kalimantan Island is from plants on the edge of the island.
Nansha Trough facilitates the entry and storage of pollen from outside area.
Pollen grains from below and above 200 m water depth are transported by rivers.