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| 1 | Zircon U-Pb geochronology of the volcanic rocks from Fanchang-Ningwu volcanic basins in the Lower Yangtze region and its geological implications显示文摘The latest eruptions in two important Mesozoic volcanic basins of Fanchang and Ningwu located in the middle-lower reaches of the Yangtze River formed the bimodal volcanic rocks of the Kedoushan Formation and ultrapotassic volcanic rocks of the Niangniangshan Formation, respectively. The repre-sentative volcanic rocks of the two Formations were selected for LA-ICPMS zircon U-Pb dating. The results indicate that there exist a large amount of magmatic zircons as indicated by high Th/U ratios in these volcanic rocks. The weighted mean age of 21 analyses is 130.7±1.1 Ma for the Kedoushan Formation, and that of 20 analyses is 130.6±1.1 Ma for the Niangniangshan Formation. These U-Pb ages are interpreted to represent the formation times of the volcanic rocks. In combination with other known geochronological data for Mesozoic volcanic rocks from the Lower Yangtze region, it is proposed that the latest volcanic activations in the Jinniu, Luzong, Fanchang and Ningwu volcanic basins probably came to end prior to ca. 128 Ma. There is no significant time interval between the early and later volcanic activities in the Luzong and Ningwu basins, suggesting a short duration of volcanic activities and thus implying the onset of an extensional tectonic setting at about 130 Ma in the Lower Yangtze region. Integrated studies reveal that the Early Cretaceous magmatic activities and their geochronological framework in the Lower Yangtze region are a response to progressively dynamic deep processes that started with the transformation of tectonic setting from compression to extension, followed by delaminating of the lower part of the thickened lithosphere, lithospheric thinning, asthenosphere upwelling, and crust-mantle interaction. | YAN Jun LIU HaiQuan SONG ChuanZhong XU XiSheng AN YaJun LIU Jia DAI LiQun | 2009 | Chinese Science Bulletin2009，54，16： | 20 |
| 2 | The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt显示文摘The Luonan-Luanchuan tectonic belt lies between the North China Block and Qinling Mountains, in- cluding the Luonan-Luanchuan fault zone and the strong deformation zone to the north of the fault. The ductile shear zone, imbricate brittle fault and duplex structure in the fault zone now are the expression of the same tectonic event in different depth. Such lineation structure exists in the tectonic belts as mineral lineation, elongation lineation, crenulation lineation, sheath folds and so on, indicating NE-directed plate motion. Fold axes and thrusts in the strong deformation zone are inclined to the Luonan-Luanchuan fault zone at small angles. The structures with different natures show a regular pattern, produced during oblique convergence of plates. The convergence factors are as follows:The direction of plate convergence is 22°, 31° and the angle between the plate convergence direction and plate boundary is 73°, 82° respectively in the west and east segment. The Luonan-Luanchuan tectonic belt was deformed strongly in 372 Ma, resulted from Erlangping back-arc ocean basin subduction sin- istrally and obliquely to North China Block during the collision of North China Block and South China Block. | SONG ChuanZhong ZHANG GuoWei WANG YongSheng LI JiaHao CHEN ZeChao CAI ZhiChuan | 2009 | Science China Earth Sciences2009，52，3： | 9 |
| 3 | A Uniform Orogen-parallel Extension System of the Shear Zones in the Tongbai-Dabie Orogenic Belt, Central China显示文摘Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in the Tongbai-Dabie complexes. However, it cannot explain the most deformations in the shear zones. The northwest-southeast shear zones are developed around or wrapped the Tongbai-Dabie complexes. They play an important role for the interpretation of the tectonic evolution of the Tongbai-Dabie orogenic belt. By a systematically observation and description of the geometry and kinematics of these shear zones, we found that the shear zones to the north dip NE and have a uniform sinistral shear sense, the shear zone to the south dips SW and has a uniform dextral shear sense, and the shear zones at the core are sub-horizontal and have a uniform top-to-NW sense of shear. Combining with the comparison of previous and our geochronological studies, we interpret these associations as indicating that these shear zones were originally a single, more flat-lying and subhorizontal shear zone with a uniform top-to-NW shear sense before the folding-doming of the TongbaiDabie complexes and suggest that the Tongbai-Dabie orogenic belt experienced a uniform top-to-NW orogen-parallel extension in the ductile lithosphere before the widespread magmatism in the Cretaceous. | LIU Huan LIN Shoufa SONG Chuanzhong | 2018 | Acta Geologica Sinica(English Edition)2018，92，2： | 3 |
| 4 | RELATIONSHIP BETWEEN P-T CONTITIONS OF TWO PHASES OF TAN-LU STRIKE-SLIP SHEAR ZONES AND DELAMINATION OF OROGENIC BELTS ON THE EASTERN MARGIN OF THE DABIE MOUNTAINS显示文摘The Tan-Lu fault zone joins the Dabie Mountains on its eastern margin, and offsets the Dabie and Sulu orogenic belts sinistrally for about 500 km. On the basis of calculation of temperature and pressure experienced by the two phases of the fault zone as well as the thermo-chronological information on mylonite from the earlier and later Tan-Lu fault zones on the eastern margin of the Dabie Mountains, this paper discusses the delamination history and uplifting magnitudes of the Dabie Mountains from earlier Jurassic to earlier Cretaceous. From mineral assemblages, mineral deformation and muscovite-chlorite geothermometry calculation, it is known that the temperature experienced by the two phases of Tan-Lu fault zones are between 400℃ and 450℃, and the confining pressures are between 0.25Gpa and 0.36GPa for the earlier shear zones and 0.24-0.39GPa for the late shear zones. According to the geobarometry of Si-in-phengite and by considering shear heating and tectonic over-pressure, it is concluded that the maximum formation depths for the two phases of the ductile shear zones are not more than 12 km. Differential formation depths for the two phases of shear zones are 1-2 km at most. At about 190 Ma and 128 Ma, the Tan-Lu fault zone experienced two phases of cooling events. During this period, the eastern margin of the Dabie Mountains experienced a tectonic calm period and no uplifting. According to information from the Tan-Lu fault zone, the uplifting magnitudes of the Dabie orogenic belts are not more than 12 km during the earlier Cretaceous. | WANG Yongsheng ZHU Guang WANG Daoxuan LIU Guosheng SONG Chuanzhong | 2005 | Geotectonica et Metallogenia2005，29，2： | 2 |
| 5 | The Grade-Tonnage Model for China's Molybdenum Deposits显示文摘The authors have studied the statistical characteristics of China's molybdenum deposits to establish the grade-tonnage model based on the data updated to the end of 2010. The results showed that each type of China's molybdenum deposits complied with Lasky's law approximately and the characteristics of grade-tonnage model obey the lognormal distribution. However, there are poor correlations between grade and tonnage respectively. Ultimately, we aimed to fit the grade-tonnage model through the known distribution function, draw the cumulative probability curves, and evaluated undiscovered mineral resources of China's molybdenum deposits by means of Monte Carlo simulation integrated in MRAS. | WANG Zhong XIAO Keyan SONG Chuanzhong | 2012 | Acta Geologica Sinica(English Edition)2012，86，3： | 2 |
| 6 | The Geological Significance of the Deformation and Geochronology of the Xiaotian–Mozitan Shear Zone in the Dabie Orogenic Belt(East-Central China)显示文摘The Xiaotian–Mozitan Shear Zone(XMSZ)is the boundary of the Dabie High-grade Metamorphic Complex(DHMC)and the North Huaiyang Tectonic Belt.It was deformed in ductile conditions with a top-to-NW/WNW movement.Geothermometers applied to mineral parageneses in mylonites of the shear zone give a temperature range of 623–691°C for the predeformation and 515–568°C for the syndeformation,respectively,which indicates a retrograde process of evolution.A few groups of zircon U-Pb ages were obtained from undeformed granitic veins and different types of deformed rocks in the zone.Zircons from the felsic ultramylonites are all magmatic,producing a weighted mean 206Pb/238U age of 754±8.1 Ma,which indicates the time of magmatic activities caused by rifting in the Neoproterozoic.Zircons from the granitic veins,cutting into the mylonites,are also of magmatic origin,producing a weighted mean 206 Pb/238 U age of 130±2.5 Ma,which represents the time of regional magmatic activity in the Cretaceous.Zircons from the mylonitic gneisses are of anatectic-metamorphic origins and are characterized by a core-mantle interior texture,which yielded several populations of ages including the Neoproterozoic ages with a weighted mean 206 Pb/238 U age of 762±18 Ma,similar to that of the felsic ultramylonites and the Early Cretaceous ages with a weighted mean 206Pb/238U age of 143±1.8 Ma,indicating the anatectic metamorphism in the Dabie Orogenic Belt(DOB).Based on integrated analysis of the structure,thermal conditions of ductile deformation and the contact relations of the dated rocks,the activation time of the Xiaotian–Mozitan Shear Zone is constrained between~143 Ma and 130 Ma,during which the DOB was undergoing a transition in tectonic regime from compression to extension.Therefore,the deformation and evolution of this shear zone plays an instrumental role in fully understanding this process.This research also inclines us to the interpretation of it as an extensional detachment,with regard to the tectonic properties of the shear zone.It may also be part of a continental scale extension in the background of the North China Block’s cratonic destruction,dominated by the subduction and roll-back of the Paleo-Pacific plate,but more detailed work is needed in order to unravel its complicated development. | HUANG Peng SONG Chuanzhong XIAO Wenjiao LI Jiahao ZHOU Kefa WANG Jinlin NIJIATI Abuduxun LI Zhenwei | 2021 | Acta Geologica Sinica(English Edition)2021，95，2： | 1 |
| 7 | New Zircon U-Pb Ages of the Shirenshan Gneiss, North Qinling and Their Geological Implications显示文摘The Qinling Orogenic Belt(QOB)is a composite continental orogenic belt that has experienced many tectonic events.The QOB is subdivided into the following three litho-tectonic units:the North Qinling terrane,the Middle Qinling microplate and the South Qinling terrane.The North Qinling Terrane(NQT)underwent destruction and lithospheric thinning during the late Mesozoic,accompanied by extensive magmatic activity and increased surface heat flux,led to large-scale tectonic extension(e.g.,Ren Shenglian et al.,2016).The Shirenshan gneiss is located along the contact between the NQT and the North China Block(Fig.1).Previous studies suggested that it was produced as a result of the northward subduction of the NQT beneath the North China Block(e.g.,Wang Jingya et al.,2017).Therefore,it is significant to study its structural geology,petrology,geochemistry and chronology in order to understand the tectonic settings and the interaction between the Middle Qinling microplate and the North China Block. | WANG Jingya REN Shenglian JIANG Dazhi DONG Shuwen LI Jiahao LI Longming GE Can SONG Chuanzhong HAN Xu LI Zhenqiang | 2019 | Acta Geologica Sinica(English Edition)2019，93，1： | 0 |
| 8 | Tectonic Characteristics, Evolution, and Significance of the Zhouwang Fault, Lower Yangtze Area, Eastern China显示文摘Fault geometry, kinematics, geophysics, the tectonic stress field and tectonic evolution of the Zhouwang fault in the southern Jiangnan tectonic transition zone of the Lower Yangtze region, eastern China are examined. Field observations show the fault is composed of a series of nearly E–W trending, N–S dipping faults, and four stages of tectonism(sinistral strike-slip, thrust nappe, normal fault, and dextral strike-slip) developed in turn. Geophysical data show that the fault trends almost linearly E–W along a flat, steep gravity gradient at shallow depth, with distinct gravity anomalies to the north and south and different in the north and south. Also, the deep part is characterized by northward dip and a gradual slowing down. Tectonic stress field analysis indicates that the fault experienced four tectonic movements: NNE–SSW compression, NNW–SSE compression, NEE–SWW extension, and E–W compression. Combined with regional tectonic background and previous research results, this indicates that:(1) the Zhouwang fault experienced sinistral strike-slip movement during the Indosinian Period(260–200 Ma);(2) thrust nappes developed during the early Yanshanian Period(163–145 Ma);(3) a normal fault occurred in the late Yanshanian Period(125–65 Ma);and(4) dextral strike-slip movement occurred in the Himalayan Period(ca. 50–37 Ma). The results reveal the tectonic evolution of the fault during Mesozoic deformation in the area, and also reveal the geological evolution and tectonic transformation of the Lower Yangtze region, which is key to our understanding of intracontinental deformation in eastern China. | ZHANG Gang CHEN Guangtao REN Shenglian GE Can LIN Shoufa SONG Chuanzhong LI Longming | 2022 | Acta Geologica Sinica(English Edition)2022，96，2： | 0 |
| 9 | Deformation of the Shirenshan Block in the North Qinling显示文摘Objective The Qinling orogenic belt is a typical complex continental orogenic belt which has experienced multiperiod tectonic evolution and where some important tectonic belts formed.The Luoluan fault is one of the most important belts,which is the boundary fault of the North China Plate and the Qinling orogenic belt.The Shirenshan block is located in the north section between Luanchuan and Fangcheng of the Luoluan fault.The north part | WANG Jingya REN Shenglian LI Jiahao LI Quanzhong SONG Chuanzhong LI Longmin LIN Shoufa HUANG Yonglong HAN Xu LI Zhenqiang | 2017 | Acta Geologica Sinica(English Edition)2017，91，1： | 0 |
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