Palynological Study of the Devonian - Carboniferous Boundary in the Vicinity of the International Auxiliary Stratotype Section, Guilin, China

摘要

Palynological data from Guping Section in the vicinity of the International Auxiliary Stratotype Section of the Devonian -Carboniferous Boundary, Guilin, China, have been obtained for the first time. Two miospore zones have been established: Pmr, Pml. These two assemblages, which contain latest Devonian palynomorphs, can be correlated very well with those in Byelorussia, Poland, and West Europe, as well as Central Hunan in China. Consequently, four miospore evolutionary stages in the above mentioned areas are proposed, i.e. (1) Retispora lepidophyta dominant stage; (2)R. lepidophyta and Vallatisporites pusillites coexisting stage; (3) V. pusillites dominant stage; (4) R. lepidophyta reoccurring stage. The Pmr and Pml zones in Guilin may be attributed to stage (3) and stage (4) respectively. The disadvantage of using the disappearance of R. lepidophyta and V. pusillites as the criterion for recognizing Devonian -Carboniferous boundary has also been discussed.