Time filter

Source Type

Wang Y.,Chinese Academy of Geological Sciences | Dong S.,Nanjing University | Shi W.,Chinese Academy of Geological Sciences | Chen X.,Chinese Academy of Geological Sciences | Jia L.,Hebei Institute of Regional Geological and Mineral Resource Survey
International Geology Review | Year: 2017

The western Daqingshan area, located in the eastern Yinshan belt, is dominated by the southern Daqingshan fold-and-thrust system and the northern Shiguai basin. Based on detailed structural investigations, stratigraphic controls, and geochronology, a three-stage tectonic evolution is proposed for the western Daqingshan area during the Jurassic. The discovery of syndepositional normal faults in the Early–Middle Jurassic sequences suggests that an N–S extensional regime (ca. 200–170 Ma) characterized the first deformational stage, which controlled the initial formation of the Shiguai basin. Subsequently, the relatively expansive rift basin was dissected by the initial development of the Daqingshan fold-and-thrust system that was associated with a N–S compressional regime (ca. 170–160 Ma). This phase of deformation involved the Lower–Middle Jurassic synrift sediments into a series of E–W-trending compressional structures, and controlled the deposition of Late–Middle Jurassic Changhangou growth strata ahead of the deformation front. Finally, the progression of Daqingshan fold-and-thrust system was dominated by NW–SE compression (ca. 160–145 Ma), which converted the previous E–W-trending compressional structures into a stepped geometry marked by several NE-trending oblique footwall ramps, and resulted in the depocentre of the Late Jurassic Daqingshan synorogenic conglomerate migrating markedly northeastwards. The driving mechanisms for these three palaeostress fields are considered as asthenosphere upwelling following Permian–Triassic collisional orogenesis, closure of the Mongol–Okhotsk Ocean, and NW-directed subduction of the Palaeo-Pacific plate, respectively. © 2017 Informa UK Limited, trading as Taylor & Francis Group


Wang X.-J.,China University of Geosciences | Wang X.-J.,Gold Geological Institute of CAPF | Wang G.-H.,China University of Geosciences | Li G.-D.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 6 more authors.
Geology in China | Year: 2013

Located at the westernmost end of Yarlung Zangbo suture zone, the BangguoriBoku ophiolite belt is composed of NW-striking Bangguori ophiolite and Boku melange 128 km in length and 5-10 km in width. Bangguori ophiolite consists of harzburgite and lherzolite comprising olivine (Fo =85.2̃88.0, 86.6 on average), enstatite (Mg# =89.3̃94.3, 91.2 on average), and diopside (Mg#=89.3̃94.3, 93.1 on average), characterized by high Al2O3 (0.96%̃2.10%) and Ti (173̃261 ß μg/g), close to the trace element content of MOR mantle rock, and depletion of REE with 2 REE being 0.33̃0.71 times that of chondrite. Moreover, major and trace element characteristics indicate that Bangguori ophiolites are restites resulting from 6%̃12% partial melting of the primitive mantle. Boku melange consists of groundmass of slate and silty slate, and rock mass of peridotite, gabbro, siliceous rock, sandstone and limestone. Studies show that Baoguori -Boku ophiolite belt was formed during Late Cretaceous, as evidenced by isotope dating of Bangguori ophiolite and radiolarians fossils from the silicolite rock mass of Boku melange. The results obtained by the authors demonstrate that Bangguori Boku ophiolite belt resulted from Neotethys ocean subduction, and Bangguori ophiolite represents the residuum of Neotethys ocean lithosphere and belongs to the typical MORtype ophiolite.


Chen H.-Y.,China University of Geosciences | Chen H.-Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Li S.-R.,China University of Geosciences | Zhang X.-B.,China University of Geosciences | And 5 more authors.
Bulletin of Mineralogy Petrology and Geochemistry | Year: 2012

The study of wall rock alteration in the Jinqingding gold deposit shows that there are pyritization silicification-sericitization, silicification- sericitization and potash-alteration from proximal to distal. It is showed that, from shallow to deep strata, the alteration zone of potassic become wider and the beanpoded structure occurs in some places, and that silicification- sericitization is developed commonly in the shallow stratum but repeatedly disappears in deep strata, and that pyritization silicification-sericitization only occurs in the shallow stratum. The analytical results of Au related trace elements (Ag, As, Hg) indicated that their contents increase gradually from the unaltered granite to the slightly altered granite and to the strongly altered granite in the ore body. It is concluded that wall rock is not the main source of the ore-forming material, and that the main role of the wall rock is to cause chemical property changes of the hydrothermal fluid by cooling it down and to contribute to ore formation at certain special spaces.


Wang X.J.,China University of Geosciences | Wang G.H.,China University of Geosciences | Zhuan S.P.,Hebei Institute of Regional Geological and Mineral Resource Survey | Li G.D.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 2 more authors.
Acta Petrologica Sinica | Year: 2011

A series of metamorphosed and deformed granitoid roeks occurred in Baoertu area, middle Tianshan of Northwest China. After comprehensive study of petrology, mineralogy and geochemistry, such granitoid rocks are identified as typical calc - alkaline granitoids with following characters: high levels of Hf and Hi, lower content of Li , Nb and Ta, the medium REE total, medium negative abnormity of Eu, and V-type REE distribution pattern. All of them indicate that the rocks are Caledon-I type and syn-collision granitoids. Ages of zircon were determined by LA-ICP-MS. Geochronology of U-Pb shows three ages, including 1207 ± 87Ma, 455.6 ± 1.8Ma and 433 ± 19Ma. The first age of 1207 ± 87Ma represents that of clastic zircon, reveals old basement of Proterozoic existed in Baoertu area. The second age of 455. 6 ± 1.8Ma indicates Baoertu pluton was intruded in Late Ordovician, which represents an important collision events while northern Tianshan ocean subducted southward beneath the middle Tianshan land mass. In Early Silurian about 433 ± 19Ma, Baoertu pluton was re-built by the metamorphism which indicated a metamorphism had occurred in the area of middle Tianshan, Northwest China. Such results are significant to reveal the tectonic evolution in the area of middle Tianshan, Northwest China.


Wang X.-J.,China University of Geosciences | Wang G.-H.,China University of Geosciences | Pan L.-C.,Hebei Institute of Regional Geological and Mineral Resource Survey | Wang D.-Q.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 2 more authors.
Northwestern Geology | Year: 2011

The cherts of Qiergusitao Formation show the addition of more foreign substances with high content of SiO 2, and great transformable content of Al 2O 3, and TiO 2. Also the high ratios of Si/(A1 + Fe+Mn), Al/(Al+Fe+Mn), MnO/TiO 2, and Al 2O 3/(Al 2O 3+ Fe 3O 2) reflect that the cherts of Qiergusitao Formation are the biochemical cherts and formed in a continental margin. Moreover, the Fe 2O 3/TiO 2-Al 2O 3/(Al 2O 3+Fe 2O 3) diagram shows that Qiergusitao Formation formed in a continental margin as well. Meanwhile the cherts of Qiergusitao Formation have high content of REE, unobvious enrichment of HREE, low ratios of (La/Ce) shale, high values of δCeshale and typical NASC-normalized flat REE patterns without visible negative anomaly and visible leaning to the left. Furthermore the characteristics of the lanthanon element show that the cherts of Qiergusitao Formation are the biochemical cherts and formed in a continental margin. In addition, the (La/Ce) shale-Al 2O 3/(Al 2O 3+Fe 2O 3) diagram proves that Qiergusitao Formation formed in a continental margin. And the samples of Qiergusitao Formation have the high content of trance element Hf, low content of Li, Nb, Rb, Sr, Ta, Th, U, V and Zr; unobvious enrichment of Co and Ni, the high ratios of Co/Ni, and low ratios of U/Th. The characteristics of the trace element show that the cherts of Qiergusitao Formation is normal biochemical origin.


Zhang Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Chen H.,Hebei Institute of Regional Geological and Mineral Resource Survey | Wei W.,Hebei Institute of Regional Geological and Mineral Resource Survey | Shen Z.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 3 more authors.
Geological Bulletin of China | Year: 2016

The Ermaying Formation, previously assigned to Middle Triassic, is distributed in Xiabancheng-Pingquan area and mainly composed of fluvial red sandstone and mudstone rocks. During 1∶50000 regional survey, the authors discovered for the first time a layer of rhyo-tuffite in the upper part of the Ermaying Formation. Zircon LA-ICP-MS U-Pb dating of the tuff sample yielded an age of 234.2±2.6Ma (MSWD=3.2). In combination with fossils, intrusive rocks and lithology, the authors hold that a more appropriate sedimentary time of the Ermaying Formation in northern Hebei may be Middle to Late Triassic. Furthermore, the appearance of tuff interlayer, as the response to a volcanic events, might be related to the collision between the Siberia Block and the North China Block during Middle to Late Triassic. © 2016, Science Press. All right reserved.


Guo J.-C.,Hebei Institute of Regional Geological and Mineral Resource Survey | Xu X.-M.,Hebei Institute of Regional Geological and Mineral Resource Survey | Chen H.-Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Li X.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 2 more authors.
Northwestern Geology | Year: 2014

During 1 : 50000 scale regional survey, the author discovered that the ultramafic rocks from Altun ophiolite tectonic mixtite belt are mainly composed of plagioclase pyroxene amphibo- lite, pyroxene peridotite, and serpentinized peridotite. Geochemistry of the diabase shows that the geochemistry of the major is characterized by low contents of SiO2, CaO, K2O, Na2O and high contents of MgO and FeO. With a low DI value (0. 35-14. 45), the magmatic differentiation is not obvious; while the solidification degree, with a high SI value (47. 82-70. 05), is relatively high. The ultramafic rocks belong to calcium series and magnesian ultrabasic rock, with the Ritt- man index of 0. 97 and the M/F index from 1. 94 to 4. 39. Among the compositions, the TiO2 content in pyroxene peridotite is close to that of mid-ocean ridge mantle (0. 10%-0. 40%). Characteristics of rare earth element and trace element are similar to those of mantle peridotite. All these characteristics indicate that the ultramafic rock is a part of ophiolite suite derived from the primitive mantle. The plagioclase pyroxene amphibolite may be ultramafic diamictite. Mean- while, the authors firstly got the U-Pb age (510. 60±1. 40 Ma) of zircon from pyroxene peridotite and hold that its age is considered to be the Cambrian and it may represent early products of South Altun oceanic basin.


Xu X.-M.,Hebei Institute of Regional Geological and Mineral Resource Survey | Guo J.-C.,Hebei Institute of Regional Geological and Mineral Resource Survey | Chen H.-Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Duan X.-L.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 2 more authors.
Northwestern Geology | Year: 2014

The Ordovician gabbro was firstly discovered in Changshangou, Xinjiang province. The authors got for the first time the zircon U-Pb age [444. 9±3. 4 Ma (n= 9, MSWD=1. 83)] of gabbro, whose occurence may represent a magmatic event after the closure of south Altun o- cean basin. Geochemical analysis show that the differentiation index (DI) is 35. 26 to 44. 76 and the solidification index (SI) is 20. 24 to 31. 43, which reflects a lower differentiation degree of magmatic crystallization; the values of Rittmann index (3.26-9.49) and A/CNK (0.75-0.82) indicates that the gabbro is quasi-aluminous calc-alkaline to alkaline series; the content of REE is relatively high (XlREE =237. 39× 10-6-329. 26× 10-6), the fractionation of LREE and HREE is obvious ( (La/Yb)w = 6. 14-8. 55), the REE patterns show right oblique feature and unobvious negative Eu anomaly. Trace elements show enrichment of Ba, Hf, Rb, Th, U; the value of Rb/ Sr is from 0. 04 to 0. 47, clearly lower than the average of continental crust. Combined with regional geological background and R1-R2 diagram, the authors hold that the gabbro is mantle-derived intrusive rock resulted from the plate uplift stage from pre-collision to post-collision, controlled by deep and major faults on the south of Altun. It is considered that the gabbro was formed in an extensional tectonic environment, probably be a result of lately extensional event after the closure of south Altun ocean basin.


Dong H.-K.,Hebei Institute of Regional Geological and Mineral Resource Survey | Guo J.-C.,Hebei Institute of Regional Geological and Mineral Resource Survey | Chen H.-Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Ti Z.-H.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 4 more authors.
Northwestern Geology | Year: 2014

The intrusive rocks in the Changshagou area of Altun of Xinjiang province include py- roxenite, gabbro, diabase gabbro, quartz diorite and quartz monzodiorite. Both field geological characteristics and LA-ICP-MS zircon U-Pb dating show that the rocks formed in Ordovician. Basic-ultrabasic intrusive rock has the characteristics of mantle source type; intermediate-acidic intrusive rocks show dual characteristics of type I and type S, with its magma coming mainly from the upper mantle. Assimilation by blending in part of the crust-source material in the process of magma invasion endows the rock with the nature of crust-mantle mixed source magma. Formed in continental cracking tectonic environment, the basic-ultrabasic intrusive rocks are the product of plutonic magmatism related to deep fault and continental rift, while the intermediate-acid intrusive rocks are resulted in convergence tectonic environment.


Chen H.-Y.,Hebei Institute of Regional Geological and Mineral Resource Survey | Zhang Y.-Q.,Hebei Institute of Regional Geological and Mineral Resource Survey | Zhang J.-D.,Hebei Institute of Regional Geological and Mineral Resource Survey | Fan Y.-G.,Hebei Institute of Regional Geological and Mineral Resource Survey | And 4 more authors.
Geological Bulletin of China | Year: 2014

Controversy has long existed over the ages of Jurassic strata in Chengde basin, northern Hebei. The authors obtained for the first time the U-Pb age (163.4Ma±1.1Ma) of zircon from tuff of the Jiulongshan Formation. In combination with ages of other Jurassic strata, the authors hold that the age of the Jiulongshan Formation is most likely in the range of 159~165Ma, suggesting an epoch between late Middle Jurassic and early Late Jurassic. This result indicates that the Jiulongshan Formation should belong to Callovian-Oxfordian period. Petrochemical and geochemical analyses show that the tuff is of peraluminous, K-high, and calc-alkaline nature, with A/CNK being 6.31~16.22. The ΣREE values range from 190.96×10-6 to 340.68×10-6, and the REE patterns show right-oblique feature and obvious negative Eu, Sr anomalies. Trace elements show enrichment of LILE (large ion lithophile elements) such as Rb, Ba, Th and U and depletion of HFSE (high field strength elements) such as Nb, Ta and Zr. The REE distribution patterns and trace elements characteristics of tuff in Jiulongshan is similar to those of the upper crust which had been partially melted by greywacke.

Loading Hebei Institute of Regional Geological and Mineral Resource Survey collaborators
Loading Hebei Institute of Regional Geological and Mineral Resource Survey collaborators