Geological Setting And Metallogenesis Of Lehua-Dexing Metallogenic Belt In Northeastern Jiangxi Province

Lehua-Dexing metallogenic belt locates in Wannian building unit and ophiolitic melange of the Northeast in Jiangxi, which they had formed for collision orogenic process in the middle of Huanan area. The updating focus of studing orogenic belt on its formation, the geodynamic background of UHP belt and its uplifting mechanism, no more attention relationship mineralization and orogeny in the orogenic belt. The major contents in this thesis are the common issues about the mineralization of the orogenic belt as below:(1)Based on the thorough research of the tectonic evolves in district, alteration stratum of front Sinian Period, the geochemistry of volcanic rocks and magma, author tally up the geology background of ore-forming.(2)Based on studing the characteristics of geology and geochemistry for representative deposits, the constitute and evolvement of structure-magma-fluid-diagenesis and metallogenesis system are summarized, at the same time, discussed the coupling relation of orogenic process with metallogenesis.(3)With appled harvests to the work of metallogenic prognosis, perspective area of ore-forming and prospecting target area are optimized.Mainly making new progress and understandings as below:(1)This paper deals with the tectonic evolution since the Jinningean Period , arriving finally at the following conclusions:This area has undergone multistage orogeny involving three major stages of the formation of folded basement, the ocean-continent transformation and the within continent evolution during four tectonic cycle from the Jinningean Period to Caledonian,then to indo-chinese epoch and Yanshanian.(2)On the basis of analysis for major elements,trace elements,isotope,fluid inclusion, we first make sure cause of formation for cherts which it was hydrothermal sedimentary operation, issue the relation hydrothermal sedimentary metallogenesis with ore formation.On this foundation, we sum up the whole process that the Jinshan golddeposit was formed: origin mineral resource layer→regional metamorphism→dynamicmetamorphism → hydrothermal sedimentary → reformed and superimposed.Therefore ,this dissertation establish five-stages mineralization model for it.(3)The diagenesis and metallogenesis system are analysis in which ore-forming are controlled by structure and magma and fluid.we think that the polycycle activities of magma are controlled by the deep seated...