Compaction rates of sediments or volcaniclastic material are needed to reconstruct original thickness of a bed, which in turn is required to reconstruct subsidence rates, sea-level rise, or in the case of volcanielast...Compaction rates of sediments or volcaniclastic material are needed to reconstruct original thickness of a bed, which in turn is required to reconstruct subsidence rates, sea-level rise, or in the case of volcanielastic, the location or direction of the eruption site. The knowledge of compaction rates can also aid in the reconstruction of deformed fossils. The known shape of deformed fossils can allow the determination of the compaction they experienced. Here we report the compaction rate in an early Permian volcanic tuff from Wuda, Inner Mongolia, determined from the deformation of standing tree fern stems of known anatomy. The compaction rate has been found to be 0.56 in this case, indicating that 44% of original thickness remains.展开更多
Noeggerathiales are an extinct group of sporebearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe,Nort...Noeggerathiales are an extinct group of sporebearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe,North America,and East Asia.The order Noeggerathiales includes over 50 species of more than 20 fossil genera,but their paleoecology is not well understood yet.Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands.Noeggerathiales have never been recorded in coal ball floras.Thus,it is up to now uncertain whether this group has contributed to the formation of coal.Recent investigations of an Early Permian peat-forming flora of the Taiyuan Formation near Wuda,Inner Mongolia,which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peat-forming vegetation but could even be the dominant group in some areas of the coal swamp.The Noeggerathiales in this particular peat-forming forest include Tingia unita,Paratingia wudensis,and a new species of Paratingia.Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched(monocaulous)stem.展开更多
基金supported by the Chinese Academy of Science Project KZCX2-EW-120National basic Research Program of China (973 Program, 2012CB821901)+2 种基金the National Natural Science Foundation of China to J. W.a grant from the University Research FoundationOther funding from the University of Pennsylvania to H. W. P. during field research
文摘Compaction rates of sediments or volcaniclastic material are needed to reconstruct original thickness of a bed, which in turn is required to reconstruct subsidence rates, sea-level rise, or in the case of volcanielastic, the location or direction of the eruption site. The knowledge of compaction rates can also aid in the reconstruction of deformed fossils. The known shape of deformed fossils can allow the determination of the compaction they experienced. Here we report the compaction rate in an early Permian volcanic tuff from Wuda, Inner Mongolia, determined from the deformation of standing tree fern stems of known anatomy. The compaction rate has been found to be 0.56 in this case, indicating that 44% of original thickness remains.
基金supported by the Chinese Academy of Science Project (KZCX2-EW-120)the National Basic Research Program of China (2012CB821901)+1 种基金the National Natural Science Foundation of China (41072010,41172006,41372011)a grant from the University Research Foundation of the University of Pennsylvania
文摘Noeggerathiales are an extinct group of sporebearing plants of uncertain systematic position that are known from Carboniferous and Permian age Euramerican and Cathaysian floras that occurred in present-day Europe,North America,and East Asia.The order Noeggerathiales includes over 50 species of more than 20 fossil genera,but their paleoecology is not well understood yet.Previously this group had been found only in extrabasinal floras or those inhabiting clastic wetlands.Noeggerathiales have never been recorded in coal ball floras.Thus,it is up to now uncertain whether this group has contributed to the formation of coal.Recent investigations of an Early Permian peat-forming flora of the Taiyuan Formation near Wuda,Inner Mongolia,which was preserved in a volcanic ash fall has provided evidence that noeggerathialean plants not only existed in the peat-forming vegetation but could even be the dominant group in some areas of the coal swamp.The Noeggerathiales in this particular peat-forming forest include Tingia unita,Paratingia wudensis,and a new species of Paratingia.Exceptionally well-preserved specimens indicate that these noeggerathialean plants are small trees with a canopy of compound leaves and strobili near the top of an unbranched(monocaulous)stem.
