1.Objective The Lanqi Basin about 790 km2 in size is located in the Zhenglan Banner area,to the south of the Erlian Basin,and it is not only the tectonic transition region between the North China Craton and the Xingme...1.Objective The Lanqi Basin about 790 km2 in size is located in the Zhenglan Banner area,to the south of the Erlian Basin,and it is not only the tectonic transition region between the North China Craton and the Xingmeng orogenic belt,but also the area between the Great Khingan Mountains volcanic belt and the northern Hebei-western Liaoning volcanic belt.Its key tectonic location involves the Paleo-Asian Ocean,the Mongol-Okhotsk suture zone and the transition of the Paleo-Pacific tectonic domain,which should be paid more attention to.What's more,the Lanqi Basin is controlled by two groups of faults in the NE and NW directions,respectively.Among them,the NW faults are mainly small in scale,while the NE faults are basement faults those are the main controlling fault for volcanic eruption.展开更多
A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is...A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.展开更多
基金This study was financially supported by the China Geological Survey Project(DD20190099).
文摘1.Objective The Lanqi Basin about 790 km2 in size is located in the Zhenglan Banner area,to the south of the Erlian Basin,and it is not only the tectonic transition region between the North China Craton and the Xingmeng orogenic belt,but also the area between the Great Khingan Mountains volcanic belt and the northern Hebei-western Liaoning volcanic belt.Its key tectonic location involves the Paleo-Asian Ocean,the Mongol-Okhotsk suture zone and the transition of the Paleo-Pacific tectonic domain,which should be paid more attention to.What's more,the Lanqi Basin is controlled by two groups of faults in the NE and NW directions,respectively.Among them,the NW faults are mainly small in scale,while the NE faults are basement faults those are the main controlling fault for volcanic eruption.
基金This study was performed under the China Geological Survey(Grant no.DD20190172)the Sino Probe(Grant no.2017YFC0602806)。
文摘A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.