Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of thi...Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.展开更多
Research on the characteristics of faults and their evolutionary history since the Cretaceous in the Suhongtu-Dagu depressions can provide a theoretical basis for geological evaluation of the coal seams in the Suhongt...Research on the characteristics of faults and their evolutionary history since the Cretaceous in the Suhongtu-Dagu depressions can provide a theoretical basis for geological evaluation of the coal seams in the Suhongtu Formation in the northern-central region of the Yin’e Basin.Using 3-D seismic-logging inversion techniques,seismic stratigraphic calibration,stratigraphic sequence delineation,and thickness calculations on the Suhongtu-Dagu depressions were carried out to clarify the planar and profile distributions of the faults,as well as the evolutionary history of these faults and the tectonic history of the depressions.The results of this study revealed that the distribution of the faults in the Suhongtu-Dagu depressions in the northern part of the Yin’e Basin varies with region,and the fault system was multi-period,orthotropic,north-east-trending,and north-north-east-trending,with a certain degree of inheritance in terms of the geological setting.Three types of faults were identified:Y-shaped fractures,reverse Y-shaped fractures,and parallel fractures,which can be classified as Paleozoic-Cenozoic continuous syncline faults and intra-depression faults from the top of the Permian to the Upper Cretaceous series and inter-stratigraphic adjustment faults within the Cretaceous System,respectively.The evolution of these faults can be divided into three phases:the controlling faults were the faults that existed before the Early Cretaceous and had been active since then;synclinal faults that formed during the Early Cretaceous;and modified faults that formed since the Early Cretaceous.The development and modification of the coal seams in the Cretaceous Suhongtu Formation in the Hari,Kuanzihu,and Babei sags were strongly controlled and influenced by a multi-phase complex fault system.展开更多
基金the Geological Science and technology foundation of Shandong Provincial Bureau of Geology and Mineral Resources (Grant No. 20080037)
文摘Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.
基金We thank LetPub for its linguistic assistance during the preparation of this manuscript.This work is granted by the National Natural Science Foundation of China(Grant No.42272152)the Major Projects from the Changqing Oilfield of PetroChina(No.ZDZX2021)+2 种基金the Fundamental Research Funds for the Central Universities,CHD(No.300102272205)the Fundamental Research Funds for platform of Liangshan Characteristic Agriculture(015/500827)the Innovation and Entrepreneurship Training Program for University Students,CHD(No.G202210710050).
文摘Research on the characteristics of faults and their evolutionary history since the Cretaceous in the Suhongtu-Dagu depressions can provide a theoretical basis for geological evaluation of the coal seams in the Suhongtu Formation in the northern-central region of the Yin’e Basin.Using 3-D seismic-logging inversion techniques,seismic stratigraphic calibration,stratigraphic sequence delineation,and thickness calculations on the Suhongtu-Dagu depressions were carried out to clarify the planar and profile distributions of the faults,as well as the evolutionary history of these faults and the tectonic history of the depressions.The results of this study revealed that the distribution of the faults in the Suhongtu-Dagu depressions in the northern part of the Yin’e Basin varies with region,and the fault system was multi-period,orthotropic,north-east-trending,and north-north-east-trending,with a certain degree of inheritance in terms of the geological setting.Three types of faults were identified:Y-shaped fractures,reverse Y-shaped fractures,and parallel fractures,which can be classified as Paleozoic-Cenozoic continuous syncline faults and intra-depression faults from the top of the Permian to the Upper Cretaceous series and inter-stratigraphic adjustment faults within the Cretaceous System,respectively.The evolution of these faults can be divided into three phases:the controlling faults were the faults that existed before the Early Cretaceous and had been active since then;synclinal faults that formed during the Early Cretaceous;and modified faults that formed since the Early Cretaceous.The development and modification of the coal seams in the Cretaceous Suhongtu Formation in the Hari,Kuanzihu,and Babei sags were strongly controlled and influenced by a multi-phase complex fault system.
