| Southwestern Fujian province is situated on southeastern China tectonic-magmatic-metallogenic belt,bordering on the Pacific Ocean. And it is in the juncture of Nanling polymetal belt and eastern China continentalmargin metallogenic belt. During geological history, this area has experienced the Transformation from Tethyan-Himalayan tectonic domain into circum-Pacific tectonic domain. Since Mesozoic-Cenozoic era, Because offavorable metallogenic setting caused by the strong affection of the Pacific plate, this area has become a signaturetin metallogenic area among circum-Pacific polymetal belt. Owing to complicated tectonic evolution, thetransverse and longitudinal inhomogeneity of crustal structure and the close relationship between space-timedistribution of tin deposits and crustal structures, the locations, types, sources of ore-forming material and thermalfluid of tin deposits situated in different locations show obvious differences.Guided by the tectonic systematic and ore controlling structural theory, this paper considers tectonic systemevolution and tin mineralization and metallogenic law in southeastern Fujian province as the main studyingaspects. Based on geological investigation in the field accompanying with lots of analysis and test, modelingways and methods such as the measurement of paleo-teetonic stress by TEM, measurement of the magneticfabrics, X-ray rock fabrics, tectonic numerical modeling by finite element method, Re-Os isotopic dating,analysis of stable isotopes, the measurement of composition and temperature of fluid inclusion, and analysis ofREE and microelement, this paper studys the tectonic evolution and tin mineralization of this area in detail.According to the results gained by the means of the above ways and methods, this paper divides the tectonicunits in different phases. It describes the characteristics of tectonic deformation and paleo-tectonic systematicevolution and the compounding of tectonic system, discusses the regularity of tectonic-magmatic belt distribution.It also establishes the structural pattern of crustal and upper mental in this area. And this paper analysis thetectonic space-time evolution pattern, explores the transformation and compounding between Tethyan-Himalayantectonic domain and circum-Paeific tectonic domain in this area and the formation and evolution history ofdepression of southwestern Fujian province. Finally, it indicates that fault depression, depression and fault blockand deep structures producd by structural stress field of different tectonic phases are the main factors of tectonicevolution of this area, and at the same time, reveals the crust evolutionary trend.This paper determines tin mineralization geological conditions of the southwestern Fujian province.Comparing the several main tin belts of eircum-Pacific with each other, this paper indicates that thecharacteristics of the tin mineralization in southwestern Fujian province is similar with the one of the fareast areaof Russia having favorable tin mineralization prospection.The mineralization age of deposit is important feature of studying on metallogenisis,it is always obtained bymeans of indirect methods. Re-Os Isotope ages of molybdenum in zhongjia tin and polymetal deposit indicatethat the pattern age of zhongjia tin and polymetal deposit is from 193-196Ma, which is associated with earlyYenshanian orogenies. Through analysis of typical tin deposits of this area, this paper shows several types andmuti-phases deposits, the analysis of structures of ore-field indicates that tin mineralization and ore bodies aremainly controlled by faults and fractures of different types. This paper discusses the pattern of tin mineralizationand analysis the relationship between tectonic evolution and tin mineralization. And it studies that the zonation ofmetallogenic belts, ore fields and deposits in different scales,and according to the zoning theory, we found somePb, Zn, Cu, Ag ore shoots, mineralization form mineralization zonation. Studying on characteristic of deposit.This paper determines the norms and criteria for ore prospecting and prespecting area.
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