THE BIOSTRATIGRAPHIC SIGNIFICANCE OF THE CARBONIFEROUS FORAMINIFERA GLOBIVALVULINA MODERATA
The Global Boundary Stratotype of Section and Point(GSSP)of the Serpukhovian/Bashikirian boundary was placed at the Arrow Canyon section,Nevada,USA in 1996.It was defined by the first appearance of the conodont Declinognathodus noduliferus.However,there are still some problems in this stratotype section,such as the appearance of sedimentary hiatuses in the section and the disagreements over the evolutionary lineage of D.noduliferus,which demand for further study of auxiliary foraminiferal markers in shallow water.Can the foraminifera Globivalvulina moderata that occurred about 2.5 m above the FAD(first appearance datum)of D.noduliferus in the Arrow Canyon section be used as an auxiliary biomarker for the Serpukhovian/Bashikirian boundary?By studying specimens of Biseriella and Globivalvulina from the Fenghuangshan and Dianzishang sections in South China,taxonomic definitions of the foraminifera Biseriella parva,Globivalvulina moderata,and Globivalvulina bulloides were revised.Stratigraphic correlation indicate that G.moderata appeared first in the Late Mississippian throughout the Paleo-tethys and Arctic North America,and then can be found in other areas of North America from early Pennsylvanian,suggesting that the first appearance of G.moderata in the world was diachronous.
NETL
NSTL
万方数据
维普
