The Cenozoic uplift of Qilian Mountains is critical to comprehend the uplift and extension of the Tibet Plateau as well as the formation of the first and second steps in China's topography. This study summarized d...The Cenozoic uplift of Qilian Mountains is critical to comprehend the uplift and extension of the Tibet Plateau as well as the formation of the first and second steps in China's topography. This study summarized dynamic stratigraphic realm comprehensively on the basis of stratigraphic correlation of different Cenozoic sedimentary basin regions of the Qilian Mountains and adjacent mountains. This facilitated the re-creation of the tectonic-sedimentary evolutionary process of the Qilian Mountains and their surrounding areas. The results indicate that during the Early Paleogene(Paleocene-Eocene), the Qilian Mountains were part of an uplift realm. During the Oligocene, Guide-Xining-Lanzhou-Linxia sag basin at the northern margin of the West Qinling Mountains came into being and was subjected to sedimentation. The Suli Basin located between the North and South Qilian paleo-uplifts began to form and undergo sedimentation. Intracontinental orogenic extrusion and basin detachment occurred at the Qilian Mountains during the Miocene, which caused successive uplifts of various mountains, including the Laji, South Qinghai,Jishi, Liupan, and South Shule Mountains. Until Pliocene, Qilian Mountains uplifted continuously and resulted in the shrink,extinction and being eroded of the basins, and aeolian red clay started to accumulate.展开更多
Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined throug...Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined through its lower boundary stratotype,i.e.the continental Cretaceous/Paleogene boundary stratotype.There is no section yet found which contains continuous terrestrial deposits and biostratigraphic records of the Cretaceous-Paleogene transition in Nanxiong,Guangdong and Jiayin,Heilongjiang,there is no evidence for establishing the continental stratotype of the Cretaceous/Paleogene boundary in either area.Therefore,both the"Shanghuan stage"and"Furaoan stage"are not good candidates for the lowermost stage of the Paleocene of China.From the viewpoint of charophytes,the outcrop section of the Dangyang,Hubei Province(Central China)contains the most continuous,abundant and diverse terrestrial biostratigraphic records of the Cretaceous-Paleogene transition,in particular the early Paleocene,known so far in the world.The biostratigraphic records of ostracods in the transition are also continuous,rich,and diverse.The Dangyang outcrop section is the only section known so far in China that is a possible candidate for a continental stratotype of the Cretaceous/Paleogene boundary in China and the section is the only potential section identified to date for establishing the regional lowermost stage of the Paleocene,Paleogene and Cenozoic in China or stratotype section for the stage.展开更多
基金supported by the China Geological Survey (Grant No. DD20160345-16)the National Natural Science Foundation of China (Grant Nos. 40382039, 41372020, 41372036, 41472035)
文摘The Cenozoic uplift of Qilian Mountains is critical to comprehend the uplift and extension of the Tibet Plateau as well as the formation of the first and second steps in China's topography. This study summarized dynamic stratigraphic realm comprehensively on the basis of stratigraphic correlation of different Cenozoic sedimentary basin regions of the Qilian Mountains and adjacent mountains. This facilitated the re-creation of the tectonic-sedimentary evolutionary process of the Qilian Mountains and their surrounding areas. The results indicate that during the Early Paleogene(Paleocene-Eocene), the Qilian Mountains were part of an uplift realm. During the Oligocene, Guide-Xining-Lanzhou-Linxia sag basin at the northern margin of the West Qinling Mountains came into being and was subjected to sedimentation. The Suli Basin located between the North and South Qilian paleo-uplifts began to form and undergo sedimentation. Intracontinental orogenic extrusion and basin detachment occurred at the Qilian Mountains during the Miocene, which caused successive uplifts of various mountains, including the Laji, South Qinghai,Jishi, Liupan, and South Shule Mountains. Until Pliocene, Qilian Mountains uplifted continuously and resulted in the shrink,extinction and being eroded of the basins, and aeolian red clay started to accumulate.
基金was financially supported by National Natural Science Foundation of China (Grant Nos. 41340029, 41040024 & 40072009)
文摘Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined through its lower boundary stratotype,i.e.the continental Cretaceous/Paleogene boundary stratotype.There is no section yet found which contains continuous terrestrial deposits and biostratigraphic records of the Cretaceous-Paleogene transition in Nanxiong,Guangdong and Jiayin,Heilongjiang,there is no evidence for establishing the continental stratotype of the Cretaceous/Paleogene boundary in either area.Therefore,both the"Shanghuan stage"and"Furaoan stage"are not good candidates for the lowermost stage of the Paleocene of China.From the viewpoint of charophytes,the outcrop section of the Dangyang,Hubei Province(Central China)contains the most continuous,abundant and diverse terrestrial biostratigraphic records of the Cretaceous-Paleogene transition,in particular the early Paleocene,known so far in the world.The biostratigraphic records of ostracods in the transition are also continuous,rich,and diverse.The Dangyang outcrop section is the only section known so far in China that is a possible candidate for a continental stratotype of the Cretaceous/Paleogene boundary in China and the section is the only potential section identified to date for establishing the regional lowermost stage of the Paleocene,Paleogene and Cenozoic in China or stratotype section for the stage.
