| The southern Qinling region is one important continental ore-forming belts in China. The survey and study of the Devonian base metal sulfide deposits in this region have made remarkable progress. The research on South Qinling metallogenic belts launching in multi-direction "high" type mainly involves such fields as petrology, stratigraphy, metallogeny, geochemistry, tectonic structural geology, which has produced remarkable achievement, but the research from the perspective of fluid is comparably less. What's more, it mainly focuses on typical deposit of Devonian ore-forming zone. The starting point of the study is from basin dynamic evolution, dividing basin sediments into one-basic aspect of aqueous sediment and the other hydrothermal one, carrying out systematic research on Paleozoic fluid activities' product-hydrothermal and sedimentary rock to identify time-space distribution of episodic-fluid activities in the basin evolution's process and discussing the relationship between the basic tectonic sedimentary evolution and diagenesis-mineralization of fluid by perspective of fluid activities, so as to deduct the connection of fluid process with deep-seated structure in reverse way and to reveal mineralization effect of basin fluid forming of rock and ores ,major progress has been made as follows :1. Through a comprehensive analysis of collection of regional geological data to the South Qinling, the mechanics setting and Paleozoic continental margin hydrothermal sedimentary environment in South Qinling is further clarified from several aspects such as basement features, sedimentary records, structural events and thermal process: In early Paleozoic, South Qinling is of north passive continental margin of Yangtze plate, and the setting of plume (hot spot) is obvious; in late Paleozoic, it converted to some divided rift-sag basin controlled by strenched fault within Qinling plate, Therefore, heating-extension-thining-fault-subsidence of the crustal can be know as an element geologic environment of formation of hydrothermal sedimentary rock by synthesizing three sides feature of tectonics background and sedimentary environment and terrestrial heat background.2. Systematic studies have been launched on lead-zinc deposit of Xunyang Paleozoic Silurian system discovered by recent exploration, which first distinguish hydrothermal sedimentary rocks such as albite rock, siliceous rock, ferruginous carbonate rock, barite rock, which close associated with lead-zinc deposit in ore-bearing series, and furthermore these studies first refer to their sequence, combination, petrology, mineralogy, geochemical characteristic, contributing a lot for geologist to learn structural evolution of South Qinling Silurian basin and hot-water sedimentary genic of lead-zinc deposit.Hydrothermal sedimentary albitite below the ore-bearing rock is conformity and gradational transition with the strata in space, and it has massive, banded, brecciated structure and fine equigranular and intraclastic texture, and inner clastic texture. It is chemically characterized by enrichment in SiO2,Al2O3 and Na2O. In the Fe-Mn-(Cu+Co+Ni)× 10 diagram, all samples fall in the hydrothermal sediment field. It's ∑REE,LREE,HREE are lower than the country rocks, but the chondrite REE patterns are similar. So, it's materials are extracted from Na-rich basement rocks and sedimentary collumn underlying the albitite .Laminated and banded siliceous rocks are widely distributed in the ore-bearing rock, this siliceous rocks are chemically very pure, and their SiO2 contents exceed 89 percent. The contents of the trace elements vary considerably, and most of them are lower then their Clarke values in the earth's crust. Neverthless, the siliceous rocks are remarkable enriched in the trace elements as Zn,Pb,As,Sb and Ag. In the Fe-Mn-(Cu+Ni+Co)×10 triangle diagrams, all samples fall in the hydrothermal sediment field. The siliceous rocks are characterized by low total REE contents(the average content being 4.09×10-6),...
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