Role of inherited structure on granite emplacement: An example from the Late Jurassic Shibei pluton in the Wuyishan area (South China) and its tectonic implications
Hongsheng LiuYan ChenBo WangMichel FaureSaskia ErdmannGuillaume MarteletBruno ScailletFangfang Huang
8
Citation
136
Reference
10
Related Paper
Citation Trend
Luzong Mesozoic volcanic basin is located in the Lower Yangtze River fault-depression zone, where is the north margin of the Yangtze block. The volcanic and intrusive plutons occur widely in Luzong basin, including four formations of volcanic rocks, such as, Longmenyuan Formation, Zhuanqiao Formation, Shuangmiao Formation and Fushan Formation and 34 intrusive plutons. Based on detailed field geological work and our former geochronology research on five plutons such as Bajiatan pluton, Chengshan pluton, Huashan pluton, Huangmeijian pluton and Zongyang pluton, we further carried out systematic geology and geochronology study of intrusive plutons in the Luzong Basin. LA-ICP-MS zircon U-Pb dating for 15 plutons has been carried out, which yield the ages of Huangtun pluton (134.4 ± 2.2 Ma), Yueshan pluton (132.7 ± 1.5 Ma), Bamaoshan pluton (132.7 ± 1.9 Ma), Jianshan pluton (132.0 ± 1.3 Ma), Xiewani pluton (131.6 ± 1.1 Ma), Longqiao pluton (131.1 ± 1.5 Ma), Jiaochong pluton (129.6 ± 1.3 Ma), Tudishan pluton (127.4 ± 2. 8 Ma), Fenghuangshan pluton (128.4 ±0.9 Ma), Luolin pluton (126.3 ± 2.O Ma), Longwangjian pluton (126.5 ± 1.5 Ma), Xiaolin pluton (126.2 ± 1.8 Ma), Dagangyao pluton (125.9 ± 1.3 Ma), Batan pluton (125.1 ± 1.1 Ma), Maowangmiao pluton (123.9 ± 1.9 Ma), respectively. The epoch of plutons in the Luzong basin is 134-123Ma. According to the epoch and geological characteristics, the intrusive rocks in the Luzong basin can be divided into two stages. The early stage monzonite-diorite plutons outcrop in the north part of the Luzong basin with epoch of 134-130Ma, are controlled by NNE orient structures and volcano-structure and have close relationship with Longmenyuan and Zhuanqiao cycle volcanic activity. The late stage intrusive plutons have two types. One type is syenite and outcrops in the south part of the Luzong basin, whose epoch is 129-123Ma. Those syenite plutons are mainly controlled by NNE orient structures or volcano-structure and share close relationship with Shuangmiao and Fushan cycle volcanic activity. The other type is A-type granites and outcrops in the southeast margin of the basin, whose epoch is 126-123 Ma. Those A-type granites are controlled by regional NNE deep faults and have no relationship with the basin volcano-structures. The iron, copper, gold, lead, zinc and uranium deposits in the study area related to magmatic activities can be classified into three metallogenic seiries. The monzonite-diorite plutons have close relationship with Luohe, Nihe and Longqiao iron deposits, Yueshan lead and zinc deposit and Jingbian and Bamaoshan copper deposits. The syenite plutons have close relationship with Makou and other iron deposits. The A-type granites have close relationship with No. 3440 and other gold uranium deposits. Regionally, there are three periods (145-136Ma, 135-127Ma, 126-123Ma) of magmatic and ore-forming activities in the Middle-Lower Yangtze River Valley metallogenic belt. The intrusive plutons in the Ning-Wu basin were the products of the second and third period magmatic activity and obviously later than the first period high-K calc-alkaline intrusions related to skarn-porphyry Cu-Au mineralizations in the uplift areas in the Middle-Lower Yangtze River Valley metallogenic belt. The intrusive plutons in Luzong volcanic basin were thought to be formed under regional lithospheric extension and thinning environment which has great significance for further research and exploration.
Cite
Citations (48)
The Dongjiangkou granitic pluton is exposed in the South Qinling terrain between the Shang-Dan and the Mian-Lue suture zones.This granitic pluton generally contains abundant mafic enclaves of different types.Results of zircon U-Pb dating for a granite and two mafic enclaves by using the LA-MC-ICPMS technique show that the Dongjiangkou granitic pluton crystallized in 223Ma and mafic enclaves formed simultaneously in 222Ma.This magmatism of early Mesozoic constrains the time of tectonic transformation from compression to extension in the Qinling orogenic belt.Hf isotopic composition of zircons obtained by the LA-MC-ICPMS technique suggests that the granitic pluton resulted from a mixing-mingling process between mantle-derived mafic magma and crustal-derived granitic magma.The mafic magma originated likely from depleted mantle,while basement rocks of the South Qinling(or Yangtze) terrain contributed major material source for the granitic pluton.This magmatic activity is attributed to lithospheric delamination during the post-orogenic stage of the Qinling orogenic belt.
Cite
Citations (23)
Geochronology
Cite
Citations (62)
The Journal of the Japanese Association of Mineralogists Petrologists and Economic Geologists (1984)
The Ibaragi granitic complex in Osaka Prefecture intruded into Paleozoic formation of the Tanba Belt and consists of two separate masses, named Nose pluton and Myoken pluton. Rock type of the Nose pluton spans from quartz diorite to adamellite. While, the Myoken pluton, intruding into the Nose pluton, consists entirely of adamellite. Eighty-two specimens were collected from the two masses and were analysed by X-ray flourescence spectrometric and y-ray spectrometric methods on chemical major elements and some trace elements. The relation of SiO2 to other chemical elements in whole rock of the Nose pluton is shown in a slightly curved trend. Similar tendency is found on trace elements. On the other hand, no specific trend is identified between SiO2 and other elements of the Myoken pluton, due to its narrow SiO2 spanning. From the trace elements, however, it is divided into two groups. It could be considered that the Nose pluton was produced through a single differentiation process of parental magma. On the contrary, the Myoken pluton seems to give a suggestion that mixing might have occurred in its parental magma, in spite of its apparent homogeneity observed in the-field.
Diorite
Cite
Citations (0)
Abstract Contacts within nested plutons are crucial for constraining the relative timing of pluton emplacement and the internal geometry of composite plutons. Exposures in orogenic belts are commonly discontinuous, however, disguising these contacts. In this paper, the Merrimac plutons in the northern Sierra Nevada of California are used as an example of how composition and foliation patterns can allow the definition of unexposed contacts and identify nested plutons. Image analysis techniques were used to determine modal compositions of a total of 52 samples from the Merrimac plutons. The integrated analysis of compositional data and foliations patterns reveals a critical contact within the plutons, and suggests that the Merrimac plutons indicate way‐up towards the north‐east at the time of emplacement 142 ± 3 Ma ago. This paper provides guidelines for recognizing nested plutons in poorly exposed areas and shows that consistent structural and compositional assymmetries within nested plutons can be used as regional top‐direction indicators.
Cite
Citations (3)
Dike
Cite
Citations (239)