The Metallogenic Prediction Of The Tongshan Copper Deposit In Heihe City, Heilongjiang Province

The Tongshan copper deposit is located in the southeast of Duobaoshan about 4km, which is a large copper-polymetallic deposit. The main strata exposed in mining area are Tongshan group (O2t) and Duobaoshan Group (O2d) of the Paleozoic in the mid-Ordovician. The magmatic active strongly in the region.The volcanic rocks are represented by andesite and dacite in mid-Ordovician of Duobaoshan strata. The intrusive rocks are represented by Tongshan tonalite diorite, tonalite porphyry, Duobaoshan granodiorite and quartz diorite. The mining area is developed northwest, east-west and north-south trending tectonic. The NW structure is formed early in the mining district and belonged to the Variscan tectonic cycles , which is the basis of structure and mainly are Duobaoshan complex multi-level anticline , secondary syncline and NW ductile shear zone along the axes of NW structure. The EW and NS structure is postmineral structure and belonged to the Yanshan tectonic cycle, which include EW faults and NS faults.The No.Ⅰorebody of the Tongshan copper deposit was discovered in 1961 and maked detailed investigation in 1990-1993. The Tongshan copper deposit showing that the surface and deep (1303.8 meters of drilling hole does not penetrate the ore body) has a good exploration prospects by prospecting the orebody deep concealed the upper partⅡand the bottom ofⅢore body. The mainly identificated results of detailed survey : the number of the ore body, distribution area, occurrence, shape, thickness and its hosting rule. The deposit is composed of the four main ore bodies and and 76 subordinate ore bodies, and distribued in the 1040 -1112 lines, which is 2000 meters long, the average width of 403 meters , occurrence of elevation of +530 m and -862 m deep extension. The ore bodies showed striped-lenticular body, the overall trend 120°-128°, dip to southwest and angles70°-80°. The ore bodies both occured in the low-order joint density of chlorite sericite andesite, pyroclastic rocks, lava and quartz of sericite within tonalite rock band in the North West main structure . The metallic amount of Cu C + D class is ** million tons of metal and the average grade is 0.48%.Following the above work, the survey is mading great breakthroughs in prospecting ore , but the core area of the existing four main ore bodies has not been determined in the Tongshan mine. The manner of nappe about the No.Ⅱorebody and distribution of its bottom ore body have not yet ascertained. so far, the No.Ⅲorebody which is in footwall of the Tongshan fault is not done deep engineering work . The No.Ⅰ,Ⅱorebody are recognized as only the small part by analysis in current . It is always a thinking and controversial question about the knowledge of the Tongshan fault, the hosting location of the fault rupture and size of resources.Based on the exploration results in the previous article , the metallogenic model and prospecting theory of porphyry copper deposits at home and abroad , systematic collected geophysical and geochemical information mineralization in the study area, the ore body geology and ore-controlling factors of comprehensive analysis of field and indoor , full use of computer technology in the study area, the use of borehole data MICROMINE software to establish a database, three-dimensional model and ore grade ore body model to locate on the Tongshan copper deposit , bring up prediction proposed prospecting in the favorable areas, and on this basis, three-dimensional model under the ore body and ore grade model, lots of copper in predicting the amount of resources were estimated.The Tongshan No. I ore body is located in the north wall of stope ore body , which through the department for the Tongshan fault. There are many wall structure shaped marks. It is showed that most of the fault scratches on the walls from east to west, inclined to east, angle 10°- 20°by the field observations .It is developed multiple sets of cleavage break and NW trenching. There are also some scratches southward tilt. It is obtained that the hanging wall is mainly pushed east to west , and there are thrust from south to north by the research of these structures .The trenching of No.Ⅲore body in the footwall of fault is EW . The trenching of No.Ⅱore body in the footwall of fault is NNW . If the footwall of the ore bodyⅢsubject, in the west line 1072,ⅡⅢorebody ore body in the north, a distance of about 200 meters between the two, but in the 1112 line, the disk No.Ⅱore bodies in the footwall of the basic coverageⅢorebody above, that the fault level from east to west in addition to push, there is the 1112 line features rotation axis. 1112 lines from the west, farther away, cover the greater the distance covered. TheTongshan fault is so determined to press both north-south shear of near east-west shear fault.According to geological data the study area, three-dimensional geological spatial model, draw the following conclusions:a, The Tongshan thrust fault from east to west over a distance of 100-400m, from south to north nappe 400-600m, 400m from the bottom up about thrust.b, The No.ⅡandⅢorebody ore body has more than one identity and metallogenic model. The Tongshan Mining is composed of Tongshan group and Duobaoshan group in the mid-Ordovician, along the core of the anticline a tonalite intrusive rocks. The No.Ⅲorebody hosted in tonalite rock.The No.Ⅰ,Ⅱorebody hosted in andesite, andesitic tuff surrounding rock rock of contact ing zone in the southwest . According to the study area No.Ⅲorebody model and three-dimensional alteration, it is the main ore body in the Tongshan deposit.c,The occurrence of No. I orebody and exposed section of a sub-group of more than Dudobaoshan segment No.Ⅲorebody footwall south line of 1080 and the 1096-1112 exploration and ore body exposed a group of more than one sub-section of Baoshan formation relevant, both occurrence and scale consistent, contain andesite chlorite - sericite and copper ore body, initially speculated that the two are forming Copper Mountain thrust fault after the fault of the product . In the western end of the No.I ore body ore body (1060 prospecting line) and No.Ⅲore body on the western end of the identified ore body (1080 prospecting line) ore andesite stratigraphic correlation, the two things to the dislocation distance of 400m, that line of east-west distance of exploration 1060-1080 .d, No.Ⅱorebody footwall position of speculation.According to porphyry copper deposit model, the proposed study area 1080-1120 exploration line deep (800m below), the fault is about 200m south of the lower plate is the site of No.Ⅱore body, located in the deep mid-Variscan igneous rocks into favorable area of the edge of the mine, but also a multi Baoshan Group (synclinal transition end) favorable structural position, the study area is larger, better vision forecast area.According to the information known engineering controls, the use of No.Ⅰ,ⅡandⅢore bodies of three-dimensional copper ore body block model, quality models to estimate the amount of Cu metal (identified mineral resources) to ** t. Compared with the detailed investigation report estimation results, the three main ore body and ore metal content of the total relative error was 2.3% and 6.4%, indicating that the use of MICROMINE calculation, can objectively reflect the actual state of the ore body.According to quantitative prediction of three-dimensional positioning information, the No.Ⅲorebody is located in the footwall of the west Tongshan 1064 lines, east line until 1112, to what 1200 meters long, horizontal projection of an average width of about 150 meters, extending the depth> 1000 m, depth, width is not fully controlled, has been proven Cu metal of 60 million tons (an average delay of about 600 meters deep), the limited extrapolation, suggesting that the total metal content of Cu≥** million tons, the amount of metal added Cu≥40 million tons. No.I,Ⅱorebody ore body is located on the disk. West from the 1040 line, the east line until 1112, ore body length of 1800 meters, average width (in Tongshan the horizontal projection of the fault plane) for 220 meters, with an average grade of 0.52%, ore body weight 2.8t/m3, guess mine No.Ⅱbody of the extension in the footwall of 500 meters deep, suggesting that additional Cu metal content was 288 million tons. Predict the amount of Cu metal (potential mineral resources) of more than 300 million t. Copper Mountain Copper Mine will be the total amount of Cu metal is more than 400 million tons, will be bigger than Duobaoshan copper deposit.