As the most influential strike-slip fault in East China,the Tancheng-Lujiang fault zone draws scholars attention for its strong seismic activity. Nevertheless,most research has been conducted along segments in Shandon...As the most influential strike-slip fault in East China,the Tancheng-Lujiang fault zone draws scholars attention for its strong seismic activity. Nevertheless,most research has been conducted along segments in Shandong Province and Bohai Bay where huge earthquakes occur frequently. Meanwhile,it is generally believed that segments lying to the south of Huaihe River have been inactive since the late Quaternary and thus it is incapable of generating moderate or strong earthquakes. However,these understandings about the Tancheng-Lujiang fault have been questioned by our recent work for part of the fault south to the Huaihe River. Based on interpretation of high-resolution satellite images,detailed field investigations near Wuhe county and Mingguang City in northern Anhui Province and elaborate microstructure analysis, we come to the conclusion that the Tancheng-Lujiang fault zone mainly consists of four branches and at least one should be active since the late Pleistocene for the Wuhe-Mingguang section. This segment is monopolized by dextral strike-slip motion in late Quaternary. Different from obvious faults in bed rocks or consolidated sediments,the latest activity trace in Quaternary loose sediment revealed by trench excavation is not obvious or even invisible to visual observation. According to our recent work and previous studies, we call for more attention to be paid to invisible faults in young sediment and also suggest that more research be conducted along this seemingly placid segment.展开更多
The Tancheng-Lujiang fault zone has great influence in eastern China. Studies have shown obvious signs of neotectonic activities on the Xinyi-Wuhe segment of the Tancheng-Lujiang fault zone. In this study,on the basis...The Tancheng-Lujiang fault zone has great influence in eastern China. Studies have shown obvious signs of neotectonic activities on the Xinyi-Wuhe segment of the Tancheng-Lujiang fault zone. In this study,on the basis of the previous work,many seismological surveys are made along the Tancheng-Lujiang fault zone and trenches are excavated in key sites.Combined with the analysis of the seismic activities along the fault,the fault movement features and future seismic risk are discussed. Much first-hand information obtained in the paper can provide an important reference value for the study of large earthquake recurrence rules and the mid and long-term earthquake prediction on the Xinyi-Wuhe segment of the Tancheng-Lujiang fault zone.展开更多
A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 ...A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 cm both in length and in width. The leaf veins are well preserved and clearly visible under a low power microscope. Leaf ar-chitectural analysis shows that such a leaf should belong to the first leaf rank of Hickey, i.e. the most primitive one. There are no early angiosperm leaves published completely similar to ours. A new species name of Dicotylophyllum minutissimum sp. nov. is established for the present leaf fos-sils.展开更多
基金funded by the program of Active Faults Detection and Seismic Hazard Assessment in Hefei City,Anhui Province
文摘As the most influential strike-slip fault in East China,the Tancheng-Lujiang fault zone draws scholars attention for its strong seismic activity. Nevertheless,most research has been conducted along segments in Shandong Province and Bohai Bay where huge earthquakes occur frequently. Meanwhile,it is generally believed that segments lying to the south of Huaihe River have been inactive since the late Quaternary and thus it is incapable of generating moderate or strong earthquakes. However,these understandings about the Tancheng-Lujiang fault have been questioned by our recent work for part of the fault south to the Huaihe River. Based on interpretation of high-resolution satellite images,detailed field investigations near Wuhe county and Mingguang City in northern Anhui Province and elaborate microstructure analysis, we come to the conclusion that the Tancheng-Lujiang fault zone mainly consists of four branches and at least one should be active since the late Pleistocene for the Wuhe-Mingguang section. This segment is monopolized by dextral strike-slip motion in late Quaternary. Different from obvious faults in bed rocks or consolidated sediments,the latest activity trace in Quaternary loose sediment revealed by trench excavation is not obvious or even invisible to visual observation. According to our recent work and previous studies, we call for more attention to be paid to invisible faults in young sediment and also suggest that more research be conducted along this seemingly placid segment.
基金jointly sponsored by the Special Fund for Earthquake-related Scientific Research of China Earthquake Administration(201308012)the Anhui Provincial Natural Science Foundation(10040606Q24),China
文摘The Tancheng-Lujiang fault zone has great influence in eastern China. Studies have shown obvious signs of neotectonic activities on the Xinyi-Wuhe segment of the Tancheng-Lujiang fault zone. In this study,on the basis of the previous work,many seismological surveys are made along the Tancheng-Lujiang fault zone and trenches are excavated in key sites.Combined with the analysis of the seismic activities along the fault,the fault movement features and future seismic risk are discussed. Much first-hand information obtained in the paper can provide an important reference value for the study of large earthquake recurrence rules and the mid and long-term earthquake prediction on the Xinyi-Wuhe segment of the Tancheng-Lujiang fault zone.
基金supported by the National Natural Science Foundation of China(Grant No.39930020)State Key Laboratory of Palaeobiology and Stratigrapby(Nanjing Institute of Geology and Palaeontology,CAS)(Grant No.013106).
文摘A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 cm both in length and in width. The leaf veins are well preserved and clearly visible under a low power microscope. Leaf ar-chitectural analysis shows that such a leaf should belong to the first leaf rank of Hickey, i.e. the most primitive one. There are no early angiosperm leaves published completely similar to ours. A new species name of Dicotylophyllum minutissimum sp. nov. is established for the present leaf fos-sils.
