| Jinwozi gold deposit located in Hami city near the border with Gansu province, is a important gold productive area in eastern Xinjiang. It is situated in middle Beishan rift on the southern edge of the collision belt between Tarim-Sino Korean plate and Kazakhstan plate,belonged to Zhaobi shan-Pochengshan fourth-order precious metallogenic belt of Xingxingxia-Mingshui gold polymetallic belt. The type of Jinwozi deposit is a quartz vein complex, and it included more than 100 auriferous quartz veins,whice produced in the Jinwozi biotite granodiorite pluton. From west to east by a group of 3 pulse,10 pulse group,18 pulse group,31 pulse group, pulse 38 pulse group and the group composed of 49. Based on three vein group for example, fully on the basis of study of ore-forming geological background and ore deposit geology characteristics in the studied area, combining previous existing research results, and through field geological investigation and a large number of laboratory analysis research work, the author detailed describes the morphology and production and distribution and scale shape of auriferous quartz veins in detail, and made a deeply analyze of the faulting ore-controlling function and fine mineralization field space structure, and summarizes gold orebodies in space distribution and positioning rule, and finally discusses the further ore-prospecting in the study area. The main conclusions in this paper are as follows:1.3 vein of gold orebodies located nearly SN-trending zhang shear fault zone, whice consist of NW320°and NE10°two groups direction tracing shear fault in Jinwozi granite rock, and fracture ore-controlling effect is very obvious. Ore-controlling fracture to brittle broken mainly, and concurrently shear downward slide of high permeability and dilatancy sex for characteristics, and has the positive-left row (west dish downward toward the south) oblique sliding characteristics.It is the main channel and place for the ore-forming fluid migration and convergence, also leading and matching and integrating the ore, and restricts the gold orebodies' morphology and scale and space distribution, limits the orebody in Jinwozi rock internal development, and mainly occurs in the Lord fractures in shape by footwall dispersion-decreasing steep place. The Ore bodies are in conformity with the main fractures in attitude, and characterized by branching swollen contraction, composite and discontinuity along the trend and tendency.2. Orebodies by tracking zhang shear sex fracture structure control, have the characteristics of parallel isometric like distribution. Generally larger orebody in the interval between100～150m, while smaller orebody the interval between about 20～50m.3. Orebody has expand and contract changing characteristic along the trend and tendency in fault zone. Generally larger scale of orebodies swollen contraction variations of distance is larger, about 30 to 50m, smaller orebody expand and contract spacing is lesser, about 10～30 as well.4. Orebodies are controled by attitude of faults, mainly produce along the two groups of fracture direction, a group of nearly SN-trending, range change in 320～340°, the other group for NE10～25°. There are mainly west tilt local east, abrupt and gentle change of angle, steep parts angle can be amounted to about 80～90°, slower parts for 50～75°commonly. The characteristicsof profile is a "when an eight-lane" steep sloping lateral plunging to north-south ends, namely south to south volts and north to north, lateral plunging angle generally in 60～80°.5. Gold mineralization in space has piecewise enrichment characteristics. General central location mineralization is strong, to north-south ends are weak, and the northern is strong, southern is weak along the direction in quartz vein body. The mineralization shows strong and weak alternative changes in tendency, from one to four middle section, the behaved for middle mineralization is strong, upper and lower are weakening, mineralization may also appear enrichment below the four middle section.In addition, the mineralization are relatively strong in swollen thickening parts of quartz veins, and narrow parts are weakens. General quartz vein body swollen grows wider and mineralization relatively strong towards for 350～20°location, but there are narrow and weakly towards greater than 20°or less than 340°section.6. Gold mineralization has the characteristics of multistage superposition enrichment in space. There is considerable difference of gold enrichment strength in different mineralization stage. Mainly enrichment inⅡstage (quartz-pyrite stage) andⅢstage (gold-polymetallic sulfide stage), especially in parts ofⅡandⅢstage superposition, gold enrichment degree is the strongest, and is a strong gold mineralization symbol. But only appearⅠstage (pyrite-quartz stage) orⅣstage (quartz-carbonate stage), the gold enrichment degree and mineralization are weak, and generally does not form industrial orebody.7. The thermoelectricity coefficient of pyrite in study area reveals that each orebody pyrite thermoelectricity in cavitation model (P type) primarily, its emergence rate all in 85%. P type pyrite large distribution is orebody shallow symbol, therefore believe that the tunnel engineering control veins now are most located in the shallow in orebody hang up, deep still has good ore propects.8. The pyrite crystals of 4 orebody form top to down overall change trend for:{100} from multiple to less,{210} and{100+210} from less to more. In addition, the average thermoelectric coefficient(a) and thermoelectricity parameters (Xnp) of pyrite change grads smaller in the vertical, and erosion rate (y) is relatively low, show that 4 orebody mineralization is stable, orebody scale larger and denudation extent is relatively low, current revealed parts are in the shallow, orebody in deep has larger extension.9. The trace element vertical zoning characteristics of 4 orebody show that, orebody happened mineralization superposition in one to three middle section. Now one middle section has located in top orebody tail, and three middle section in the upper of lower orebody, whice has a certain outspread in deep. If it still happened superposed mineralization in three middle section, the extension of orebodies are greater.10. The gold grade isogram of 4 orebody reveals that, gold mineralization in space is piecewise enrichment regularity, and northern mineralization stronger than southern overall. In addition, mineralization has to south lateral prostration and could cause deep mineralization scope expanding southward.11. The study area has better ore propects through gold orebodies spatial orientation law research of 3 pulse group, whice has superior metallogenic geologic condition, more favorable known gold mineralization information and larger vertical distribution, especially developed large scale and grade high blind lode in deep, constitute a new inviting prospecting object. In addition, deep exploration engineering has also confirmed that gold mineralization still has larger outspread in the vertical. The next exploration work should be mainly concentrated in P-7-P-13 line between the deep 400 m and 800m scope of north and P-O～P-12 lines deep of middle and P-20 line south deep districts in pulse group. |
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