1、1Studying of Gold Mine Exploration and Metallogenic Regularities From Laozuo Mountain In HeilongjiangAbstract. Laozuo mountain，located on the junction of the city of Shuang Yashan and Qi Taihe,from which a large-scale vein gold deposits was discovered in the in the 1980 s. And gold mining point was
2、established on 1975 in the mountain of Laozuo that construct the development mining of the diggings on 1989.Since from now is more than 20 years,the Laozuo mountain is on the dangerous circumstance of the shortage of resources. According to the long-time survey about the project of Laozuo mountain s
3、o as to get a further studying work on prospecting and mineral deposit exploration for used mine. The research is mainly introduce the metallogenic environment and the regulation of the mineral. And based on the technology we have mastered, we can apply it into practical production. Key words: Laozu
4、o mountain Gold mine exploration Metallogenic Regularities. 1. Introduction of mineral deposit of Laozuo mountain The construction of Laozuo mountain is located on the 2center of the parcel of Jiamusi City but the submersible structural unit is established on the southeastern side. The mineral is co
5、nsist of three ore belts and hundreds of ore body. And the mineral appears of different centuries granite that mainly contains Hercynian mix granite batholith Stock Yanshan interim acid rock strain and dike. The emergence stratum mainly is Palaeozoic sediment rock series, drape, rift grow, magma act
6、ivity is delicacy which lithology mainly contains Dark clouds inclined long gneiss biotite monzonitic schist dark clouds become grain rock marble and various contact metamorphic rock. The structures development in district is across Xingkay ancient movement and Hercynian period and Yanshan period te
7、ctonic movement which appears numerous structural superposition and compound. Besides the fault zones general strike in NNWNWW, preferring SW, which is the basic of tectonic framework that will has a little work on limiting the development of late-tectogenesis. The mineralize in this area is mainly
8、with the activity of the hot lava during the Yanshan period. And the center of all of the three Ore zone mineralization occurrence have the production of the rock mass in Yanshan period.The source of ore into minerals is extracted in the process of post-magmatic 3hydrothermal activity which precipit
9、ated in the favorable host sites. By the age of K-Ar way to determined the diorite :123 146 Ma, plagioclasite :127 143 Ma. Feixiban rock is producted mainly by the character of rock wall, which is measured on the age of 98 Ma. The magmatic rocks on Yanshan period are mainly prolific on large fractur
10、e flanking, lots of small intrusions development is often on the area that a lot of the mineralization enrichment on,. The REE distribution curve is the type of LREE enrichment . LREE / HREE-3.93 of Eu values certain losses were in the middle “V“ shaped curve that reflects the characteristics of the
11、 crust-mantles transition type. The surrounding rocks alteration is appeared mostly by silicification, sericitization skarnization carbonatite. And the Silicide is often accompanied by sericitization, potassium and carbonate rocks which can be classified into two categories: one is hydrothermal quar
12、tz whose euhedral and wavy extinction is truly obvious. The aggregates were directed elongated, interspersed in the rock appears as a a small veinlets ; the other is the silicified quartz, mostly for small euhedral account feldspar which edges creep cristobalite. Sericitization mineralization is mai
13、nly distributed in the West ore zones and in mixed ore zone granite 4fracture that is often with silicide symbiotic located by way as veinlets along fractures distribution. Skarn and carbonate rocks mainly distributed in the middle ore zone and East ore zone assumes layered stratiform which is less
14、appears as lenticular. 2. The deposit characteristics: The gold deposit in Laozuo mountain is consist of the eastern, central, western belt,and there are more than 51 only in the ore zone. East ore zone is produced in Xingdong Group Malaysia River.,the formation of which is , NW, SE and eastern segm
15、ents ore block. The ore body is limited by the development in the ductile shear zone above the NWW-trending and NW-trending tensional faults and extended on both of the intersections of the most swollen ore body along strike. And the ore body surrounding rock in the Xingdong Group migmatite and skar
16、n times for marble which mixed with granite and mylonite mylonite lithified rock. The gold-bearing mineral is mainly with pyrrhotite. Central oar belt is produced in Proterozoic the mixed granite with mixed rock at the junction of the boundaries. The ore body is also affected by the superimposed abo
17、ve the ductile shear zone as the NWW and NW-trending faults control, such as along strike 5variation. The surrounding ore body is Proterozoic granite and migmatite skarn rock wall rock, times diorite porphyry and mylonite. The gold-bearing mineral includes pyrrhotite and arsenopyrite. West ore zones
18、 produced in the Proterozoic migmatitic granites within the ore bodies are controlled by NW to pressure shear fracture, the ore body to extend and the extended deep great but thickness .The gold-bearing mineral contains mainly about arsenopyrite mineralization and Yanshan small rock (vein) closely r
19、elated to the ore body. The wall rock Proterozoic is mostly contains mixed granite and Yanshan diorite porphyry, granite porphyry. 3. The gold-bearing mineral typomorphic features 3.1 Arsenopyrite Arsenopyrite in the oar area of Laozuo mountain is the most important gold-bearing mineral, which is wi
20、dely distributed. Their output is divided into early and late two for four generations (Ars T, A Danube , Ars III, A Ma ), respectively, corresponding to the early mineralization, mineralization stage and late mineralization , mineralization stages. A Lu n, Afs is coarse which is small amount of out
21、put. ArsI, Ars are n fine-grained subhedral a euhedral large number of outputs in the East Ore Zone and West 6ore zones that constitute the East Ore Zone and West Mineral bonanza. Arsenopyrite content and form of to showing regular changes in different parts of the ore body. Mine early arsenopyrite
22、Fe / (As + S) value substantially close to the theoretical value.Wherein the average value of the I Generation 0.502 ,generations II 0.497,late arsenopyrite Fe / (As + S) values significantly less than the theoretical value, , generations were 0.490,0.425,Fu S, As, characteristic losses Fe. From the
23、 value of As / s, early I, generations were 1.003,1.023. Late , generations were O. 933, O. 935, indicating early arsenopyrite rich As and late arsenopyrite-rich S. 3.2 Pyrite Pyrite generated in the early stages II and the late , stage, divided into PyI, Py II Py III and Py four generations. Less t
24、he volume of output of the mine early mineralization stage pyrite by late mineralization period of Py III Py IV chemical composition analyzed: the principal component S, Fe were lower than the theoretical value, especially sulfur deviate from greater average 3.92% lower. S / Fe values are less than
25、2, showing a loss s characteristics and with the loss S extent of the stronger, with higher Au contains. 73.3 Pyrrhotite Pyrrhotite, as we all know is also an important gold-bearing mineral, in Laozuo mountain ,distribution in the ore zone and East ore zone, the main outputs of the first mineralizat
26、ion stage, in the early mineralization period late only a small amount of output. Analyzed by the X-ray curve, early pyrrhotite divided into hexagonal pyrrhotite late monoclinic pyrrhotite. Higher the early output pyrrhotite Au content, are indicative the orebody typomorphic mineral, the average con
27、tent of major elements Fe atoms is significantly less. 3.4 Sphalerite, galena Minerals of galena and sphalerite mineralization stage for the late third, mainly located in the West ore zone with pyrite and arsenopyrite constitute the ore body, the central and eastern ore zone, only a very small amoun
28、t of scattered distribution. Euhedral sphalerite better, cube and octahedron poly shape, lumps or Star dot uneven distribution of quartz or arsenopyrite, particle size which is generally about 3 to 5 mm .Small clusters of large piece body. Under the microscope the galena mostly euhedral cubic shape,
29、 uneven distribution of 8output, together with sphalerite veins. 4. The mineralization The gold mine Laozuo mountain macro stratabound. The Lower Proterozoic Xingdong Group Malaysia River group accounts for about 10% of the area, while about 10% of the gold deposits (points) is given a set of strata
30、 or edge exists. The study suggests that the strata owns multilayer gold source layer. Xingdong group distribution in late Archean the metamorphic geological around the lithology is mainly the biotite plagioclase leptynite, plagioclase gneiss, marble, migmatite. Metamorphic protolith in mafic volcan
31、ic rocks, rich in carbon, magnesium limestone and argillaceous arkose deposition construction series, is a continental margin geosyncline product. This set owns higher gold content of rocks, dispersion. Refer to the information summary to know the source of the gold in mafic volcanic eruption. Sourc
32、e of ore gold enrichment are two ways, one is gold with in the mafic - felsic magma upwelling into the Trough the cold solidification of the magma is fixed in the rock; The other is volcanic hydrothermal or volcanic jet - the hot springs from deep ore-forming elements into the basin under reducing c
33、onditions, the case of cold sea water, due to the drastic changes in the physical and chemical 9conditions and the release of the gold. The higher strata carbonaceous, organic carbon can produce strong reducing environment. Into the basin in gold, in this environment can easily be restored to a natu
34、ral gold and settle down in a reducing environment, divalent iron ions in the sediment more, combined with hydrothermal sulfur to form sulfide (similar to the yellow iron ore) deposited layer of sulfide ore source close symbiotic relationship with Kim. Migmatization hydrothermal carbonate rocks mutu
35、al metasomatism form skarn and Cuiqu formation gold and be enriched. Skarn sporadic distribution in the granitic rocks, the direction of the spreading direction of regional metamorphic relicts are roughly the same and has some layers. The distribution of the different types of skarn stratigraphic re
36、asonable (gneiss gneissosity). Skarn mineral assemblages. With diopside, garnet marble, is actually a regional metamorphic rocks. Make it easier for these skarn or skarn formation process gold activation, transfer, enriched form of gold mineralization. The late Proterozoic then ductile shearing occu
37、rred gold further enrichment in the East ore belt and belt development. The Late Proterozoic Xingdong movement of late, accompanied by 10geosynclinal fold return and a wide range of regional metamorphism, the occurrence of strong migmatization and granite metamorphism of late with the development of
38、 anatexis formed in situ mixing granite associated with the granite and Lower Proterozoic Xingdong Group, was batholith output more with the surrounding rock into invasive lending, local granite formation and invasive thermal action, the gold has been further enriched formation gold mineralization b
39、ody. 5. The marks of gold ore prospecting The geochemical traits duality of: The siderophile of chalcophile and siderophile pro-sulfur of the basic conditions for its discussion of the relationship with the mineralization. T o think the siderophile resistance under high temperature and pressure cond
40、itions is gold relative enrichment and was decentralized mode of occurrence; Gold can be dissolved and to hydrothermal form of migration is due to the the gold pro sulfur ;Gold precipitation and enrichment the main reason is the changing nature of the ore-forming fluid system. At the same time, with particular emphasis on the role of carbon in a stable gold solubility and mineralization process. Therefore, gold siderophile mantle source concept based on gold chalcophile into the crust and as the basis of
