| Dayingezhuang gold deposit, which is located at the southeast margin of the Northwest Jiaodong uplift, and bounded on the middle of Zhaoping fault and on the east of the Tanlu fault, is one of the super-large tectonic alteration gold deposits characterized by "large depth, huge reserve and low grade" This gold orebody occurs in the Zhaoping fault, which is the contact zone of the linglong granite and metamorphic rock of. Jiaodong GroupConsulting the literatures and earliest formal geological survey, and being guided by the polygenetic compound theory of Chen Guoda,, this paper conducts outfield and regional geological survey, ore field geological researches, structure analysis, petrography study, trace element analysis, fluid inclusion tracing, stable isotope analysis and so on, to construct multiphase diagenesis model and hydrothermal convection model for gold deposit in Dayinge county.Investigations on the outcropping rocks in the research area show that the origin of greenstone basement protolith is from mafic volcanic rock and sedimentary rock. And some mafic rocks, like amphibolite and gabbro, is originated from mantle tholeiitic magma erupted in the tensional marin facies, and the Linglong granite from the remelting of greenstone protolith. The linglong granite is bearing abundant Si, Al, Ba, Si and Na, but fewer Mg, Y, Yb, Ti and HREE, positive Eu anomaly, and high Mg#. This is the like C-type adakite, implied from its occurrence there was an eastern plateau in the Mesozoic. The Guojialing granite, the crust-mantle mixed type, was formed under the extensional structural movement. And diorite porphyry and lamprophyre, high potassium-potassic type intermedia-mafic dykes, suggest that Jiaodong area had undergonethe extensional tectonic movement in the late Me sozoic. Subject to the researches on the occurrence, scale, and grade of the orebody, the component of ore, structure, ore types, alteration types and alteration zoning, Dayingezhuang gold mineralization is divided into two periods and six stages. Analysis of fluid inclusions, including petrography, type, temperature, pressure, salinity, density and characteristics of compositions in the six stages, indicate that, from the early to late stage,(1) the inclusions evolve from the gas+vapor-liquid+CO2-bearing vapor-liquid-liquid inclusions to the liquid+vapor-liquid inclusions;(2) temperature, pressure and salinity keep to fall down;(3) the compositions of the inclusions vary from H2O-CO2-CH4-H2S to H2O-CO2-CH4-SO2; and (4) the mineralizing condition changes from reduction to oxidation.The results of hydrogen-oxygen isotope data show that (1) the genesis of ore-forming fluids in the Dayingezhuang gold deposit come from mantle and magmatic fluids at the early stage, then mostly the meteoric water;(2) the fluids in the Linglong granite involve metamorphic and mantle fluids. The test of carbon isotope also shows that the source of ore-forming fluids come from deep-depth, and then converge with other fluids. The results of sulfur isotopes show that the sulfur in the Jiaodong area is inheritable and the sulfur isotope range are the most similar to Guojialing granite, which suggests that the sulfur here apparently comes from Guojialing granite. Lead isotopes also show that the genesis of ancient lead had the identical inheritance as sulfur isotopes, and lead isotopic data plot in a straight line with a relatively steep slope, which indicates that the genesis of the lead might come from the crust and the mantle.This paper synthetically investigates the characteristics of structure-control, strata-control and rock-control, and goes through a deeply discussion on multi-source characteristics of ore-forming materials, fluids and dynamics, especially on the characteristics, transportation, precipitation and mechanisms of ore-forming fluids, and systematically discusses the typical characteristics of super-large plastic shear zone with polygenetic-compound theory.The mineralization of Diwa stage is subject to hydrothermal convectionsystem, which implies that this area may host other potential deposits, especially in its lower part.
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