The qualities of petrology and paleobiology in Wuzhishan Section are studied. Several geo-chemical anomalies are recognized, such as: high rare earth element content, high pyrite content and Ni anomalies. It could be ...The qualities of petrology and paleobiology in Wuzhishan Section are studied. Several geo-chemical anomalies are recognized, such as: high rare earth element content, high pyrite content and Ni anomalies. It could be correlated with Nandong Section in Xiangzhou County and the F/F boundary could be determined according to Ni anomalies. The results of the study indicate that the geochemical anomaly plays an important role in stratigraphic correlation in non-fossil stratum.展开更多
Research on chemo-biostratigraphy reveals that the periodic fluctuation of Ce/La ratios in carbonate sequence may reflect Milankovitch 100 ka eccentricity cyclicity. The Ce/La curve of the upper Famennian of Huangmao ...Research on chemo-biostratigraphy reveals that the periodic fluctuation of Ce/La ratios in carbonate sequence may reflect Milankovitch 100 ka eccentricity cyclicity. The Ce/La curve of the upper Famennian of Huangmao (Guangxi) may be well correlated to that of Muhua (Guizhou) and of Mid-Tarim (Xinjiang). They correspond not only in curve-feature, but also in number of cycles. Huangmao and Mid-Tarim are now located 3 000 km apart, during the Devonian possibly they were located farther apart. This study proves that the simultaneous sedimentary record of Milankovitch eccentricity cycles with a recurrent interval of 100 ka may be traced at different long-range sites. These cycles simultaneously developed in different depositional settings among different facies suites as a result of regional to global climate forcing, thus supporting the Milankovitch Theory.展开更多
A suite of event deposits, isochronous and interrelated in origin, occurs widely near the Frasnian- Famennian boundary in Guangxi, South China. It is mainly distributed in the facies areas of the platform-margin slope...A suite of event deposits, isochronous and interrelated in origin, occurs widely near the Frasnian- Famennian boundary in Guangxi, South China. It is mainly distributed in the facies areas of the platform-margin slope and inter-platform rift-trough. The rudstone or calcirudite occur in the Liujing section of Hengxian and Luoxiu and Baqi sections of Xiangzhou in the facies area of platform-margin slope. The turbidites are observed in the sections of Yangdi and Baisha of Guilin, Du'an of Debao, Nandong and Sanli of Wuxuan, Xiangtian, Ma'anshan of Xiangzhou, Nayi of Chongzuo, Yunpan of Shanglin in the facies area of inter-platform rift-trough. The massive homogenites occur in sections of Mangchang, Luofu and Road from Nandan to Tian'e and Ma'anshan etc in the facies area of inter-platform rift-trough. Herein event deposits can be correlated in stratohorizon to the turbidite in the bottom of the Lower triangularis Zone in Hony railroad cut of Belgium, Devils Gate of Nevada, USA, Atrous of Morocco, South Urals and Fore-Kolyma of northeastern Siberia of Russia, and erosional discontinuities and brecciation in the Frasnian-Famennian boundary in South Polish-Moravian shelf. The event deposits could be caused by a violent tsunami related to bolide impacts into ocean.展开更多
On the basis of the faunas including conodonts Palmatolepis gracilis sigmoidalis, P.gracilis gracilis, Polygnathus germanus, which are found for the first time, and corals Cystophrentis kalaohoensis it is confirmed th...On the basis of the faunas including conodonts Palmatolepis gracilis sigmoidalis, P.gracilis gracilis, Polygnathus germanus, which are found for the first time, and corals Cystophrentis kalaohoensis it is confirmed that the Changjiang Formation refers to the Famennian, and may correlate with the Shaodong Formation and Menggongao Formation of central Hunan. This is the only Devonian deposits known in Hainan Island so far. It means that the outstanding problem of whether the Devonian rocks exist in that island is now settled. Meanwhile, the new evidences indicate that the lectostratotype section of Nanhao Formation of Baoting area refers to the Silurian,rather than the Lower Carboniferous as considered by most geologists formerly. Furthermore, the Member 3 of Nanhao Formation at Shilu-Jinbo district is proved to be the Upper Carboniferous,rather than Tournaisian or Middle-Upper Devonian as deemed to be before.展开更多
In the Tarim Basin (in the Xinjiang Uygur Autonomous Region, Northwest China), the Frasnian-Famennian (F-F) boundary and boundary events within the Upper Devonian are revealed by applying the chemo-biostratigraphic me...In the Tarim Basin (in the Xinjiang Uygur Autonomous Region, Northwest China), the Frasnian-Famennian (F-F) boundary and boundary events within the Upper Devonian are revealed by applying the chemo-biostratigraphic method. At Bachu County, Tarim Basin, the F-F boundary is placed near the base of the Middle Member of the Bachu Formation. This result indicates that the important oil-reservoir bed, Donghe Sandstone, has an age no later than the Frasnian. Nickel anomalies and gypsum beds in the F-F boundary beds might have an origin of rifting-hydrothermal process.展开更多
文摘The qualities of petrology and paleobiology in Wuzhishan Section are studied. Several geo-chemical anomalies are recognized, such as: high rare earth element content, high pyrite content and Ni anomalies. It could be correlated with Nandong Section in Xiangzhou County and the F/F boundary could be determined according to Ni anomalies. The results of the study indicate that the geochemical anomaly plays an important role in stratigraphic correlation in non-fossil stratum.
文摘Research on chemo-biostratigraphy reveals that the periodic fluctuation of Ce/La ratios in carbonate sequence may reflect Milankovitch 100 ka eccentricity cyclicity. The Ce/La curve of the upper Famennian of Huangmao (Guangxi) may be well correlated to that of Muhua (Guizhou) and of Mid-Tarim (Xinjiang). They correspond not only in curve-feature, but also in number of cycles. Huangmao and Mid-Tarim are now located 3 000 km apart, during the Devonian possibly they were located farther apart. This study proves that the simultaneous sedimentary record of Milankovitch eccentricity cycles with a recurrent interval of 100 ka may be traced at different long-range sites. These cycles simultaneously developed in different depositional settings among different facies suites as a result of regional to global climate forcing, thus supporting the Milankovitch Theory.
基金the National Natural Science Foundation of China (Grant No. 40621002)"111" Project (Grant No. B08030)MOE Innovative Research Team Program (Grant No. IRT0546)
文摘A suite of event deposits, isochronous and interrelated in origin, occurs widely near the Frasnian- Famennian boundary in Guangxi, South China. It is mainly distributed in the facies areas of the platform-margin slope and inter-platform rift-trough. The rudstone or calcirudite occur in the Liujing section of Hengxian and Luoxiu and Baqi sections of Xiangzhou in the facies area of platform-margin slope. The turbidites are observed in the sections of Yangdi and Baisha of Guilin, Du'an of Debao, Nandong and Sanli of Wuxuan, Xiangtian, Ma'anshan of Xiangzhou, Nayi of Chongzuo, Yunpan of Shanglin in the facies area of inter-platform rift-trough. The massive homogenites occur in sections of Mangchang, Luofu and Road from Nandan to Tian'e and Ma'anshan etc in the facies area of inter-platform rift-trough. Herein event deposits can be correlated in stratohorizon to the turbidite in the bottom of the Lower triangularis Zone in Hony railroad cut of Belgium, Devils Gate of Nevada, USA, Atrous of Morocco, South Urals and Fore-Kolyma of northeastern Siberia of Russia, and erosional discontinuities and brecciation in the Frasnian-Famennian boundary in South Polish-Moravian shelf. The event deposits could be caused by a violent tsunami related to bolide impacts into ocean.
基金the National NaturalScience Foundation of China (Grant No. 49972094), and Development Foundation of Geolgical Science and Technology (Grant No. Hy 979820).
文摘On the basis of the faunas including conodonts Palmatolepis gracilis sigmoidalis, P.gracilis gracilis, Polygnathus germanus, which are found for the first time, and corals Cystophrentis kalaohoensis it is confirmed that the Changjiang Formation refers to the Famennian, and may correlate with the Shaodong Formation and Menggongao Formation of central Hunan. This is the only Devonian deposits known in Hainan Island so far. It means that the outstanding problem of whether the Devonian rocks exist in that island is now settled. Meanwhile, the new evidences indicate that the lectostratotype section of Nanhao Formation of Baoting area refers to the Silurian,rather than the Lower Carboniferous as considered by most geologists formerly. Furthermore, the Member 3 of Nanhao Formation at Shilu-Jinbo district is proved to be the Upper Carboniferous,rather than Tournaisian or Middle-Upper Devonian as deemed to be before.
基金the National Natural Science Foundation of China(Grant No.49972015) the Research Fund for the Doctoral Program of Higher Education of the Education Ministry of China.
文摘In the Tarim Basin (in the Xinjiang Uygur Autonomous Region, Northwest China), the Frasnian-Famennian (F-F) boundary and boundary events within the Upper Devonian are revealed by applying the chemo-biostratigraphic method. At Bachu County, Tarim Basin, the F-F boundary is placed near the base of the Middle Member of the Bachu Formation. This result indicates that the important oil-reservoir bed, Donghe Sandstone, has an age no later than the Frasnian. Nickel anomalies and gypsum beds in the F-F boundary beds might have an origin of rifting-hydrothermal process.
