Based on detailed measurement in the field and a comprehensive analysis of carbonate microfacies,the Pennsylvanian reefal microfacies characteristic and sedimentary environment from Longjiangdong,Guangxi,China are ana...Based on detailed measurement in the field and a comprehensive analysis of carbonate microfacies,the Pennsylvanian reefal microfacies characteristic and sedimentary environment from Longjiangdong,Guangxi,China are analyzed. The twelve carbonate microfacies have been recognized including micritic / microsparitic limestone,peloidal / aggregate-grain grainstone,bioclastic wackestone / packstone,laminated mudstone,boundstone,bioclastic wackestone / packstone with single shell,coral framestone / bafflestone,bioclastic packstones /grainstones with abundant benthic foraminifera or crinoids,wackestone / mudstone with calcispheres,bioclastic packstone / grainstone,unname reef-building organism framestone and brachiopod grainstone. In addition,four facies have been identified including open platform facies,restricted platform facies,coral reefal facies and shoal facies. According to analysis of microfacies combination and facies evolution,three stages and three reef units during the reef formation process have been noted. The evolution of each stage indicates a repeating fluctuation of the sea-level,but the water energy is still relatively low overall,which represents frequent changes of paleoclimate in the early Late Carboniferous.展开更多
Phylloid algae arc important rcef-builders in the late Carboniferous. This paper focuses on the paleoecology of phylloid algae in the Late Carboniferous on well-exposed reefs in Ziyun County, Guizhou Province. Phylloi...Phylloid algae arc important rcef-builders in the late Carboniferous. This paper focuses on the paleoecology of phylloid algae in the Late Carboniferous on well-exposed reefs in Ziyun County, Guizhou Province. Phylloid algae growing closely packed arc attached via holdfast or similar structure to substrate. They were growing in environments such as shallow water, photic zone and below the wave base with medium energy currents. They have a variety of morphological forms, such as single cup-shaped, cabbage-shaped and clustering cup-shaped. The thalli arc of certain tenacity and intensity. In the areas dominated by phylloid algae, other marine orgam＇sms arc relatively scarce. Obviously, phylloid algae arc stronger competitors for living space than other co-occurring organisms.展开更多
We collected, processed, identified, and analyzed the spores and pollen samples from the Zhuanchengzi Bed of the Yixian Formation in the Yingwoshan area of western Liaoning. As a result, we confirm a palynomorph assem...We collected, processed, identified, and analyzed the spores and pollen samples from the Zhuanchengzi Bed of the Yixian Formation in the Yingwoshan area of western Liaoning. As a result, we confirm a palynomorph assemblage of Cicatricosisporites-Protoconiferus. The pollen was primarily from gymnosperms, dominated especially by conifer pollen. Pteridophyte spores were less common and some questionable angiosperm pollen occurred occasionally. The age of the palynomorph assemblage is dated as the late Valanginian or Hauterivian-Barremian stage, the Early Cretaceous. The study applies the concept of Palynological Vegetation based on palynological spectra and the paleoecological characteristics of palynological taxa for the first time. Palynological vegetation type, climatic zone type, and humidity type are divided quantitatively for the Zhuanchengzi Bed in the Yixian Formation of western Liaoning. We then obtained the evolutionary trends. The results showed that the overall climate was warm and humid during the deposition period of the Zhuanchengzi Bed in the Yixian Formation. Palynological vegetation types are various and include coniferous forest, deciduous broadleaf forest, evergreen broad-leaved forest, grass, and shrubs. The local temperature changed from warm to much warmer and from a semi-humid to humid climate. Palynological vegetation types are always dominated by coniferous forest. The coexistence of deciduous broad-leaved forest, evergreen broad-leaved forest, shrubs, grass, and some xerophytic plants indicates vertical zonation and seasonal climate change The vertical vegetation types and the warm humid climate may imply a large geomorphological contrast in the Yixian Formation of western Liaoning.展开更多
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20120042110027,20110042120043)the National Natural Science Foundation of China(No.41202018)
文摘Based on detailed measurement in the field and a comprehensive analysis of carbonate microfacies,the Pennsylvanian reefal microfacies characteristic and sedimentary environment from Longjiangdong,Guangxi,China are analyzed. The twelve carbonate microfacies have been recognized including micritic / microsparitic limestone,peloidal / aggregate-grain grainstone,bioclastic wackestone / packstone,laminated mudstone,boundstone,bioclastic wackestone / packstone with single shell,coral framestone / bafflestone,bioclastic packstones /grainstones with abundant benthic foraminifera or crinoids,wackestone / mudstone with calcispheres,bioclastic packstone / grainstone,unname reef-building organism framestone and brachiopod grainstone. In addition,four facies have been identified including open platform facies,restricted platform facies,coral reefal facies and shoal facies. According to analysis of microfacies combination and facies evolution,three stages and three reef units during the reef formation process have been noted. The evolution of each stage indicates a repeating fluctuation of the sea-level,but the water energy is still relatively low overall,which represents frequent changes of paleoclimate in the early Late Carboniferous.
基金This study is supported by a grant （No. 40572014） from National Science Foundation of China （NFSC）.
文摘Phylloid algae arc important rcef-builders in the late Carboniferous. This paper focuses on the paleoecology of phylloid algae in the Late Carboniferous on well-exposed reefs in Ziyun County, Guizhou Province. Phylloid algae growing closely packed arc attached via holdfast or similar structure to substrate. They were growing in environments such as shallow water, photic zone and below the wave base with medium energy currents. They have a variety of morphological forms, such as single cup-shaped, cabbage-shaped and clustering cup-shaped. The thalli arc of certain tenacity and intensity. In the areas dominated by phylloid algae, other marine orgam＇sms arc relatively scarce. Obviously, phylloid algae arc stronger competitors for living space than other co-occurring organisms.
基金supported by National Natural Science Foundation of China(Grant No.41172003)National Basic Research Program of China(Grant No.2012CB821905)Education Department Programs of Liaoning(Grant Nos.L2013105,L2013450)
文摘We collected, processed, identified, and analyzed the spores and pollen samples from the Zhuanchengzi Bed of the Yixian Formation in the Yingwoshan area of western Liaoning. As a result, we confirm a palynomorph assemblage of Cicatricosisporites-Protoconiferus. The pollen was primarily from gymnosperms, dominated especially by conifer pollen. Pteridophyte spores were less common and some questionable angiosperm pollen occurred occasionally. The age of the palynomorph assemblage is dated as the late Valanginian or Hauterivian-Barremian stage, the Early Cretaceous. The study applies the concept of Palynological Vegetation based on palynological spectra and the paleoecological characteristics of palynological taxa for the first time. Palynological vegetation type, climatic zone type, and humidity type are divided quantitatively for the Zhuanchengzi Bed in the Yixian Formation of western Liaoning. We then obtained the evolutionary trends. The results showed that the overall climate was warm and humid during the deposition period of the Zhuanchengzi Bed in the Yixian Formation. Palynological vegetation types are various and include coniferous forest, deciduous broadleaf forest, evergreen broad-leaved forest, grass, and shrubs. The local temperature changed from warm to much warmer and from a semi-humid to humid climate. Palynological vegetation types are always dominated by coniferous forest. The coexistence of deciduous broad-leaved forest, evergreen broad-leaved forest, shrubs, grass, and some xerophytic plants indicates vertical zonation and seasonal climate change The vertical vegetation types and the warm humid climate may imply a large geomorphological contrast in the Yixian Formation of western Liaoning.
