The Naij Tai Group-complex is a suite of tectonic-sedimentary méiange aggregation of the Eastern Kunlun orogenic belt, which is composed of two parts, i.e. the exotic blocks of various ages and the matrix strata....The Naij Tai Group-complex is a suite of tectonic-sedimentary méiange aggregation of the Eastern Kunlun orogenic belt, which is composed of two parts, i.e. the exotic blocks of various ages and the matrix strata. On the basis of coral, brachiopod and gastropod fossils found in the exotic blocks, the age of this group-complex was once defined to the Late Ordovician or the Paleozoic. This paper reports for the first time 44 genera and 31 species of Mid-Late Oiigocene sporopoilen in samples from the matrix strata in this group-complex and the Paleogene Quercoidites-Persicarioipollis assemblage is named. The paper aims to provide some detailed evidence for determining the age of the matrix strata in this group-complex based upon a study at the Caiyuanzigou section, which would be of great geological significance for further understanding this group-complex as a suite of tectonic-sedimentary méiange aggregation. The new finding will certainly benefit from now on the investigation of formation and evolution mechanism for the Eastern Kunlun orogenic belt.展开更多
Parametamorphic rocks from Arong County in southeastern Inner Mongolia- Daxinganling district are regarded as Proterozoic in age, belonging to the Wolegen Group and composed of volcanoclastic and sand- stone in origin...Parametamorphic rocks from Arong County in southeastern Inner Mongolia- Daxinganling district are regarded as Proterozoic in age, belonging to the Wolegen Group and composed of volcanoclastic and sand- stone in origin, and have been disputed in tectonic setting. Because of the stability in metamorphism, the rare earth elements indicate the features of their protoliths. The authors integrated the petrologic methods with the geochemical parameters which include ЕREE, ЕLREE/NHREE, δCe, δEu, La/Yb, Sm/Nd, Th/Sc and the standard values of chondrite. The results show that the protoliths of Wolengen Group may be a group of volcanoclastic and continental margin clastic rocks, and their tectonic setting is the continent island arc.展开更多
Wanbaogou Group-complex is a suit of melange aggregation of the EasternKunlun orogenic belt, which is divided into two parts, i.e. the exotic blocks and the matrix strata.Based on stromatolite fossils yielded in the e...Wanbaogou Group-complex is a suit of melange aggregation of the EasternKunlun orogenic belt, which is divided into two parts, i.e. the exotic blocks and the matrix strata.Based on stromatolite fossils yielded in the exotic blocks, the age of this group-complex was oncedefined to the Precambrian. Recently, two Paleogene palynological assemblages have been found insamples from the matrix strata of the Upper Part in this group-complex by the authors: in ascendingorder, the Al-nipollenites-Quercoidites assemblage of Late Eocene and theCaryapollenites-Pinuspollenites assemblage of Early Oligocene. Those results show that the matrixstrata of this melange were mainly formed in Paleogene, and the event causing mixture should be aHimalayan Movement Phase. This paper is designed to provide some detailed evidence for determiningthe age of the matrix strata in this group-complex based upon study at the Kunlunqiao Section, whichwould be of important geological significance for further understanding this group-complex as asuit of melange aggregation and establishing or improving the stratigraphic framework of the studiedregion. The new finding will certainly benefit from now on the investigation on geotectonic andsedimentary evolution of Eastern Kunlun.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.40272019)the China Geological Survey(Grant No.200313000054).
文摘The Naij Tai Group-complex is a suite of tectonic-sedimentary méiange aggregation of the Eastern Kunlun orogenic belt, which is composed of two parts, i.e. the exotic blocks of various ages and the matrix strata. On the basis of coral, brachiopod and gastropod fossils found in the exotic blocks, the age of this group-complex was once defined to the Late Ordovician or the Paleozoic. This paper reports for the first time 44 genera and 31 species of Mid-Late Oiigocene sporopoilen in samples from the matrix strata in this group-complex and the Paleogene Quercoidites-Persicarioipollis assemblage is named. The paper aims to provide some detailed evidence for determining the age of the matrix strata in this group-complex based upon a study at the Caiyuanzigou section, which would be of great geological significance for further understanding this group-complex as a suite of tectonic-sedimentary méiange aggregation. The new finding will certainly benefit from now on the investigation of formation and evolution mechanism for the Eastern Kunlun orogenic belt.
文摘Parametamorphic rocks from Arong County in southeastern Inner Mongolia- Daxinganling district are regarded as Proterozoic in age, belonging to the Wolegen Group and composed of volcanoclastic and sand- stone in origin, and have been disputed in tectonic setting. Because of the stability in metamorphism, the rare earth elements indicate the features of their protoliths. The authors integrated the petrologic methods with the geochemical parameters which include ЕREE, ЕLREE/NHREE, δCe, δEu, La/Yb, Sm/Nd, Th/Sc and the standard values of chondrite. The results show that the protoliths of Wolengen Group may be a group of volcanoclastic and continental margin clastic rocks, and their tectonic setting is the continent island arc.
基金supported by the National Natural Science Foundation of China(Grant No.40272019)the China Geological Survey(Grant No.200313000054).
文摘Wanbaogou Group-complex is a suit of melange aggregation of the EasternKunlun orogenic belt, which is divided into two parts, i.e. the exotic blocks and the matrix strata.Based on stromatolite fossils yielded in the exotic blocks, the age of this group-complex was oncedefined to the Precambrian. Recently, two Paleogene palynological assemblages have been found insamples from the matrix strata of the Upper Part in this group-complex by the authors: in ascendingorder, the Al-nipollenites-Quercoidites assemblage of Late Eocene and theCaryapollenites-Pinuspollenites assemblage of Early Oligocene. Those results show that the matrixstrata of this melange were mainly formed in Paleogene, and the event causing mixture should be aHimalayan Movement Phase. This paper is designed to provide some detailed evidence for determiningthe age of the matrix strata in this group-complex based upon study at the Kunlunqiao Section, whichwould be of important geological significance for further understanding this group-complex as asuit of melange aggregation and establishing or improving the stratigraphic framework of the studiedregion. The new finding will certainly benefit from now on the investigation on geotectonic andsedimentary evolution of Eastern Kunlun.