East Qinling Orogenic Belt In Henan Section Of Gold Mineralization Law And Its Formation Mechanism

Conbined with the scientific research projects of Henan Non-ferrous Geological Exploration Bureau , guided by the cyustobody metallogeny, by means of traditional methods of geological research and continuum physics, characteristics of the erogenic zone,gold ore-forming laws and its controlling factors in the region are summarized, dynamical environments and mechanism of gold ore-formation are studied,mathematical models are set up,computer numerical simulations are perfomed and the direction and favorable area for gold exploration are pointed out in the dissertation.So it has important significance in the theory and practice.The research actuality and developing tendency of the fields of orogeny,geodynamics,ore-forming fluids,dynamics of ore-forming processes,Diwa theory metallogeny and so on are summarized in the dissertation. The research actuality in these fields and lack of gold metallogeny research in the region are pointed out.Based on the crustobody metallogeny,the space structure and time structure of Henan area in East Qinling orogenic zone are studied.And the region is divided into 2 I -class,3 II-class,6 III-class,45IV -class tectonic units and considered as the Diwa -type orogenic zone, which belongs to compressive -tensile type and control ore-formations of gold and non-ferrous metals seriously in the region.Oneness and variety of gold ore-formation in the region are studied. The former means that the distributions of space and time of gold deposits are controlled by "space transition ore-formation" and "time transition ore-formation". The latter embodies mainly industrial type,ore-existing stratum,ore-forming time,ore-existing structure and so on. Characteristics of gold polygenetic compound deposits in the region are demonstrated. The new viewpoint is put forward that the gold deposits in the region belong to "sediment- metamorphism-fluid superposition reconstruction" deposits which are formed by fluid superposition reconstruction in the Diwa stage' on the basis of preliminary enrichment in the fore-geosyncline,geosyncline stage.The classification of gold deposits in the region is performed on geodynamic environment first.The gold deposits in the region are divided into three types,seven sub-types.Relationship between abysmal structures and gold deposits in the region is discussed and new viewpoint is put forward that the steep slope belt in the mantle syncline and areomagnetic abnormals gradient belt jointly control the distribution of the deposits,with mechanism studied. Ore controlling of structure of region,ore field,deposit,and ore body is discussed .The contrast of gold deposits in the region and fine disseminated gold deposits home and overseas are studies and their characteristicses are summarized.The evolution of orogenic zone,gold ore-formation and its dynamic mechanism are studied and the new viewpoint is put forward that thermal stress is a main controlling factor in metamorphism,formation ,evolution of structure and ore-forming geodynamic environment. The critical condition of fluid convection in porous equal medium and the new conclusion is reached first that the thickness of structural layer and temperature gradient are main factors influencing fluid convection andtransport of ore-forming matters in additional to physical properties of rocks. According to the conclusion some mechanisms such as the transform from compressive type to tensile one of erogenic zone,transport and accumulation of ore-forming matters such as gold and so on and many ore-forming temperature values are interpreted qualitatively.The distribution equation of ore-formation fluid pressure field is deduced. Numerical simulation of ore-formation fluid pressure field in Xiongershan geodome are performed.