On the basis of researches over several years on biostratigraphy of Changhsingian at Meishan Section D in Changxing County, the abundant materials were accumulated. This paper studies the ecostratigraphy and establis...On the basis of researches over several years on biostratigraphy of Changhsingian at Meishan Section D in Changxing County, the abundant materials were accumulated. This paper studies the ecostratigraphy and establishes 7 community zones (CZ), in ascending order, Sinoplatysomus-Geinitzina-Clarkina subcarinata, Tapashanites-Nodosaria-Clarkina subcarinata, Crurithyris-Geinitzina-Clarkina subcarinata, Glomospira-Clarkina changxingensis, Colaniella-Clarkina changxingensis, Rotodiscoceras-Palaeofusulina-Hindeodus typicalis, Clarkina meishanensis-Hypophiceras .The habitat type (HT) is different from upper shallow sea to the lower part of the lower shallow sea.展开更多
The results of ecostratigraphy can directly serve sequence stratigraphy. The habitat type curve is useful not only in the analysis of sequences and parasequences, but also in demonstration of the process of regional s...The results of ecostratigraphy can directly serve sequence stratigraphy. The habitat type curve is useful not only in the analysis of sequences and parasequences, but also in demonstration of the process of regional sea level change. The various biological surfaces usually coincide with or relate to the boundaries of sequences or system tracts. The ecostratigraphic framework composed of coenozones, community sequences and ecotracts with good timing completely corresponds to the sequence stratigraphic framework of the sedimentary basin. Therefore, through establishment of the habitat type curve in individual section, recognition of the various biological surfaces, regional ecostratigraphic correlation and the formation of an ecostratigraphic framework of the sedimentary basin, ecostratigraphy plays an important role in the study of sequence stratigraphy and the reconstruction of regional and even global sea level changes.展开更多
Roof shale floras help understand the transition of vegetational landscapes from a peat–forming environment to a clastic one, but are seldom investigated in the Cathaysian province（typical present day China and East...Roof shale floras help understand the transition of vegetational landscapes from a peat–forming environment to a clastic one, but are seldom investigated in the Cathaysian province（typical present day China and East Asia）. Here the roof shale flora of Coal Seam 6 from the lower Permian Taiyuan Formation of the Wuda Coalfield, Inner Mongolia, is systematically described and its ecostratigraphic and phytogeographic implications are discussed. The flora is composed of seven plant groups, including Lepidodendrales, Medullosales, Gigantopteridales, Peltaspermales, Noeggerathiales, Cordaitales and Cycadales. Many of these taxa are also documented in Euramerica, and the floral composition indicates a more intimate relationship between Cathaysia and Euramerica during the Cisuralian than previously thought. However, there are few genera and species in common with those of the underlying peat–forming flora. Moreover, the flora is hardly comparable with the commonly known flora of the Taiyuan Formation. Such assemblage differences are very likely due to changes of taphonomic and environmental phases, rather than evolutionary floral succession. For a full and more precise understanding of the floral composition, succession and the floristic discrepancy in different depositional environments, an ecostratigraphic investigation on the Late Palaeozoic of Cathaysia is advocated.展开更多
Samples were collected continuously and systematically from Beds 2 to 30 of the Meishan D section, and nearly 4,000 foraminiferal specimens were recognized. In total, 72 species （partially including undetermined spec...Samples were collected continuously and systematically from Beds 2 to 30 of the Meishan D section, and nearly 4,000 foraminiferal specimens were recognized. In total, 72 species （partially including undetermined species and conformis species） in 34 genera of foraminifers were identified. Twelve foraminiferal community zones were established from Beds 2 to 27 based on the abundance, dominance, diversity, and equitability of the foraminiferal fauna and a functional morphological analysis of the dominant and characteristic species. The habitat type indicated by each community zone and the sedimentary features were used to determine the paleo-water depths and the relative changes in sea level. We generated curves of both the habitat type and the hydrodynamic conditions, which together indicate the relative changes in the paleo-water depth and the substrate features in the studied area during the Changhsingian. This study discusses the possible relationship between the foraminiferal community zones and the sea-level changes based on a statistical analysis of the foraminiferal community zones.展开更多
文摘On the basis of researches over several years on biostratigraphy of Changhsingian at Meishan Section D in Changxing County, the abundant materials were accumulated. This paper studies the ecostratigraphy and establishes 7 community zones (CZ), in ascending order, Sinoplatysomus-Geinitzina-Clarkina subcarinata, Tapashanites-Nodosaria-Clarkina subcarinata, Crurithyris-Geinitzina-Clarkina subcarinata, Glomospira-Clarkina changxingensis, Colaniella-Clarkina changxingensis, Rotodiscoceras-Palaeofusulina-Hindeodus typicalis, Clarkina meishanensis-Hypophiceras .The habitat type (HT) is different from upper shallow sea to the lower part of the lower shallow sea.
文摘The results of ecostratigraphy can directly serve sequence stratigraphy. The habitat type curve is useful not only in the analysis of sequences and parasequences, but also in demonstration of the process of regional sea level change. The various biological surfaces usually coincide with or relate to the boundaries of sequences or system tracts. The ecostratigraphic framework composed of coenozones, community sequences and ecotracts with good timing completely corresponds to the sequence stratigraphic framework of the sedimentary basin. Therefore, through establishment of the habitat type curve in individual section, recognition of the various biological surfaces, regional ecostratigraphic correlation and the formation of an ecostratigraphic framework of the sedimentary basin, ecostratigraphy plays an important role in the study of sequence stratigraphy and the reconstruction of regional and even global sea level changes.
基金supported jointly by the Strategic Priority Research Program (B) of of Chinese Academy of Sciences (XDB18000000)the National Natural Science Foundation of China (Grant Nos.41372011,41472005 and 41530101)
文摘Roof shale floras help understand the transition of vegetational landscapes from a peat–forming environment to a clastic one, but are seldom investigated in the Cathaysian province（typical present day China and East Asia）. Here the roof shale flora of Coal Seam 6 from the lower Permian Taiyuan Formation of the Wuda Coalfield, Inner Mongolia, is systematically described and its ecostratigraphic and phytogeographic implications are discussed. The flora is composed of seven plant groups, including Lepidodendrales, Medullosales, Gigantopteridales, Peltaspermales, Noeggerathiales, Cordaitales and Cycadales. Many of these taxa are also documented in Euramerica, and the floral composition indicates a more intimate relationship between Cathaysia and Euramerica during the Cisuralian than previously thought. However, there are few genera and species in common with those of the underlying peat–forming flora. Moreover, the flora is hardly comparable with the commonly known flora of the Taiyuan Formation. Such assemblage differences are very likely due to changes of taphonomic and environmental phases, rather than evolutionary floral succession. For a full and more precise understanding of the floral composition, succession and the floristic discrepancy in different depositional environments, an ecostratigraphic investigation on the Late Palaeozoic of Cathaysia is advocated.
基金supported by the Foundation of the Geological Survey of China [grant no. 121201004000150021]
文摘Samples were collected continuously and systematically from Beds 2 to 30 of the Meishan D section, and nearly 4,000 foraminiferal specimens were recognized. In total, 72 species （partially including undetermined species and conformis species） in 34 genera of foraminifers were identified. Twelve foraminiferal community zones were established from Beds 2 to 27 based on the abundance, dominance, diversity, and equitability of the foraminiferal fauna and a functional morphological analysis of the dominant and characteristic species. The habitat type indicated by each community zone and the sedimentary features were used to determine the paleo-water depths and the relative changes in sea level. We generated curves of both the habitat type and the hydrodynamic conditions, which together indicate the relative changes in the paleo-water depth and the substrate features in the studied area during the Changhsingian. This study discusses the possible relationship between the foraminiferal community zones and the sea-level changes based on a statistical analysis of the foraminiferal community zones.
