Oligocene palynoflora in the northern part of South China sea

Sun Xiang-Jun, Kong Zhao-Chen, Li Pun, Li Ming-Xing

Received:1900-01-01 Revised:1900-01-01 Online:1981-05-18 Published:1981-05-18
Contact: Sun Xiang-Jun

Abstract:

In the northern part of South China Sea, including Tonkin Gulf, Hainan Island,

Leizhou Peninsula and some basins of Guangdong Province, Oligocene deposits are com-

posed of motley, mainly grey, greyish green and dark red clay and sandstone, containing

very rich pollen and spores. Most of them are of the components which exsisted in

Tertiary, particularly in Oligocene deposits of Northern America and Eurasia, such as

Gothanipollis paichanensis Ke & Shi, Ulmus granopollenites Rouse, Symplocos scabro-

pollinia Traverse, Engelhardtia spackmaniana Traverse, etc. At the same time some

important Oligocene and Early Miocene pollen types of Borneo are found there, such

as Crassoretitriletes vanraadshooveni Germeraad & al., Florschuetzia semilobata Ger-

meraad & al., F. trilobata Germeraad & al., Magnastriatites howardi Germeraad & al.,

Jandufouria seamrogiformis Germeraad & al., Verrucatosporites usmansis (Hammen)

Germeraad & al., Margocolporites vanwijhci Germeraad & al., Psilatricolporites opercu-

latus Hammen & Wymstra, Monoporites annulatus Hammen and Zonocostites sp., etc.

On the other hand in Oligocene palynoflora of Borneo there appear pollen types

assigned to temperate plants or mountain plants of northern hemispherae (Pinus, Picea,

Tsuga, Ephedra and Alnus), which are found in abundence in Oligocene palynoflara of

the investigated area particularly in Late Oligocene.

All of this indicats that the palynoflora of the Northern part of South China

Sea was closely related with that of Borneo in Oligocene. This similarity of palyno-

floras in the two localities may be due to the geographycal proximity of Borneo to the

main land of Asia.

In paleoecological aspect, we have found there is plenty of pollen and spores of

land and fresh water plants, while those reflecting marine and coastal enviroments

(Rhizophora and Sonneratia) are rather scanty. This shows that in Oligocene period

the investigated area was a land. Tonkin Gulf along with Hainan Island and Leizhou

Peninsula formed an inland depression at that time.

Abundant pollen of mountain plants and temperate plants indicats, that there were

mountains in or around the area of interest.

Sun Xiang-Jun, Kong Zhao-Chen, Li Pun, Li Ming-Xing. Oligocene palynoflora in the northern part of South China sea[J]. .

Knowledge