Jiaodong is the biggest gold ore cluster in China.More than 4 500 t gold resources in total have been proved.By summarizing deep prospecting results,characteritics of typical gold deposits,and ore-controlling factors,this paper analyze the metallogenic characteristics and metallogenic regularity.Research results show that Sanshandao and Jiaojia gold deposit has developed into world-class giant gold deposit.470 t gold resources have been provided by the offshore of northern Sanshandao.In Jiaojia metallogenic belt,more than 100 t of gold resources have been provided by Qujia,Dongji-Nanlv,Nanlv-Xinmu,Zhuguolijia,Jiaojia deep and Xincheng deep ore block etc,respectively.Shaling ore block has provided 389 t of gold resources.Jiaojia and Sanshandao giant gold deposits are distributed correspondingly along Jiaojia fault and Sanshandao fault respectively,and opposite direction dip.In geological section,gold ore bodies occur in the area of flat slope of faults and inflections area where the dip angle of fault changes from steep to gentle,which shows “step-wise” distribution regularities.Now,2 metallogenic steps have be found in both Jiaojia and Sanshandao giant gold deposits.Horizontally,the turning place of fault striking and rhombic style of fault assemblage are ore-forming favored places.In Linglong gold ore field,more than 500 t gold resources of deep fracture zone altered rock type in total have been proved along Potouqing and Jiuqu fault.As a result,gold resource of altered rock type is obviously more than that of quartz vein type.From the tectonic point of view,the relation between different gold deposit type in Linglong gold ore field is the altered rocks above,the quartz veins below.In Qixia gold ore field,a large gold deposit of altered rock type is proved in Hushan village along Taiqian-Douya fault recently.This discovery opens up a new direction of prospecting in the deep of main fault zone.In Pengjiakuang gold ore field,the important achievement of deep prospecting is the discovery of Liaoshang deep gold ore deposit,which nearly 70 t gold resources have been found.The dip angles of ore-controlling fault and mineralized alteration zone in this deposit becomes gentler from shallow to deep,like shovellike,step-wise and slightly wavelike.The ore bodies host in the section of low-angle dip in depth of ore-controlling fault.Ore type of this deposit is carbonate vein type gold ore,which is different from other gold deposits in Jiaodong area.The achievements of deep prospecting in Jiaodong area indicate that deep prospecting in this area still has great potential.The key prospecting directions include:deep parts of three main metallogenic belts in Jiaoxibei area,deep parts of Qixia gold ore field and Pengjiakuang gold ore field,and the offshore of northern Sanshandao.Whereas the potential of prospecting in deep area of Linglong granite suit and Guojialing granite suit is smaller.According to the present condition of deep prospecting,it can be forecasted that there are no less than 6 000 t of gold resource above 3 000 m depth in Jiaodong area,and more than 10 000 t of gold resource above 5 000 m depth.
The breakthrough of deep prospecting of depth more than 1000 m in the Shaling mining area is the organic combination of scientific prediction and brave exploration.According to geophysical,“ladder-type” metallogenic theory,trend extrapolation and spatial distribution of ore body,three deep mineralization targets have been predicted in Shaling mining area.Then target verification and exploration work are completed in three stages following the principle of “overall deployment,phased implementation” and“studying and adjustment should be take in the process of project implementation”.There has a great breakthrough in deep exploration:77 industrial orebodies increased the amount of gold by 389 t and the single ore resources of No.Ⅰ-2 main ore body is more than 300 t,whose ore bearing elevation is -940~ -2 030 m,the maximum length of orebody trend is 1 680 m,the maximum inclination is 2 180 m,the maximum control vertical depth is 1 039 m,and thickness is 1.16~125.64 m.In conclusion,Shaling gold deposit occurs in the footwall of Jiaojia fault,the vertical distance of the continuous extension of the main orebody and its adjacent mining area is more than 2 km,much deeper than mineralization depth of the epithermal gold deposit,indicating the metallogenic environment of Jiaodong type gold deposit and epithermal deposit is obviously different,and the prospecting potential of Jiaodong type gold deposit is huge.Further analysis shows that Qianchen-Shangyangjia prediction area and Zhaoxian prediction area still have a good prospecting potential.
Moshan gold deposit which was discovered in the northeastern of Queshan rock mass and controlled by the small-sized faults and fractures,belongs to fracuture zone alteration rock pattern gold deposit.According to the comprehensive analysis of ore characteristics,main metallic mineral characteristics and gold mineral characteristics,the mineral assemblage of ore and their formation order were determined and the formation of Moshan gold deposit was dividen into three mineralization stages.This paper holds the viewpoint that mineral assemblage of Jiaodong gold deposits are distinctly different from those of orogenic gold deposits and epithermal gold deposits,and they are a unique deposit type.The research shows that gold minerals of ore are native gold,and particle size of gold mainly varies between middle and coarse,visible gold is occasionally found,in addition,the mineral composition and particle size of gold mineral in eastern Shandong have obvious differences those in northwestern Shandon,fracture development in the host rock and the long term-influence of the early Cretaceous magmatism in mining area are the main cause of forming coarse gold.
Shuiwangzhuang mining area is located in the peripheral area of the Linglong gold orefield,and the deep ore prospecting of the area is very difficult.Based on the in-depth analysis of deep metallogenic regularity of fault,this paper presents a new understanding named symmetric mineralization that the ore bearing depth and orebody scale of the three main faults in northwestern Jiaodong Peninsula are symmetrical,finds Shuiwangzhuang deep-seated super-large gold deposit where had been abandoned by foreign experts and is seized gold metal amounts to 170 t,so the depth of the exploration of the fault extends to the elevation of -2 173 m.Gold orebodies are hosted in Potouqing fault and Jiuqu fault,especially the No.2 main orebody in Jiuqu fault is the largest one,which gold metal amounts of single ore exceeds 120 t.The deep prospecting results reveal that Jiuqu fault is the main fault in the northern Zhaoping fault,the range of 1 800 m to 5 000 m along the strike of the fault (No.208) to the east of the north is high quality target area for deep ore prospection,so there is a great potential for prospecting in the deep part of Zhaoping fault.
As one of the most important gold metallogenic belts in Jiaodong region,the deep prospecting in Muping-Rushan metallogenic belt has got good results in recent years.Based on the characteristics of geology and spatial distribution of orebodies,the wall rock alterations in depth of Denggezhuang gold deposit,this study presents deep prospecting method and gives potential evaluation.Denggezhuang gold deposit is a large gold deposit,which hosts in Linglong type granites of Jurassic.The deep main orebody occurs in the elevation of -350 to -733 m,and it is controlled by the branch faults on the west of Jinniushan main fault.The mineralization favorable area should be the cross points of the NNE-striking and NE-striking faults,the turning point of the strike of faults and the location where the dip is slowed by steepness.The combination of effective methods for deep prospecting is step metallogenic model,CSAMT,borehole induced polarization measurement,EH4 system and comprehensive studies for the tectonics and geochemical halo.The combination of previous methods indicates that Muping-Rushan metallogenic belt has a good prospect of deep prospecting,as well as the regions of depth of Ⅱ-1 orebody 54 to 86 exploration lines and depth of Ⅲ-6 orebody 62 to 110 exploration lines are the favorable target area for the deep exploration.
New superlarge gold deposit is found in the northern sea of Sanshandao,Shandong Province.The hydrothermal alteration minerals of orebody mainly include muscovite,lepidolite,ilite,spodumene,epidote,kaolinite,hornblende,dolomite,calcite and smectite,as identified by short wave infrared measurement.The muscovite has close relationship with gold mineralization.Gold grade has the positive correlation with peak intensity,contrast of intensity,symmetry of peak in short wave infrared spectrum.Aluminum-poor muscovite have the indicate significance of heat center.Aluminum-poor muscovite distribute in the deep drill.With the increase of depth,there have still stable trend of aluminum-poor muscovite distribution.This shows that the depth of metallogenic heat source is deeper,indicating that the depth of gold deposit has great potential for prospecting.
The Liaoshang type,pyrite-bearing carbonate vein as the gold carrier,is a new type gold deposit summed up from deep exploration achievement.The deposit is the first large gold deposit in the northeastern margin of Jiaolai Basin.This article analyze the geological characteristics,ore controlling structure and mineralization regularity of the Liaoshang large gold deposit.The results show that the ore-bearing structure is detachment fault system developed between Jingshan group and Mesozoic granite,as well as metamorphosed basement and Mesozoic cover,and provided wide space for large scale metallogenisis.On this basis,the prospecting direction of the same type gold deposits in the northeastern margin of Jiaolai Basin is defined,which provides guidance for the further exploration in this area.
In order to predict the invalidation risk of backfilling pipeline more accurately,the evaluation model based on kernel principal component analysis and PSO-SVM is established.Eight quantitative indexes are selected as the evaluation index of failure risk of filling pipeline.And the sample data of fifteen mines were counted,which were processed by kernel principal component analysis,producing the main ingredients,as the input data of the optimized SVM model which ended up with a more accurate risk prediction on invalidation of backfilling pipeline.The results indicate that the average expected value relative errors of the five mines are below 5%.The invalidation risk assessment of backfill pipeline by the establishment of the kernel principal components analytic method and the optimized SVM model has the advantage of rapid analysis and high precision of prediction.A better evaluation is provided for the mine backfilling pipeline invalidation risk analysis.
In order to solve the problems of tailings storage and concentration device selection,a comprehensive evaluation standard system based on variable weight analysis method and TOPSIS is put forward to select a preferred solution of three schemes.Firstly,set up a comprehensive evaluation index system,taking cost,operating cost,site conditions,backfill materials properties,put-sand concentration,volume effective utilization rate,maintenance ease of cleaning and working efficiency into consideration.Because of the conventional methods such as analytic weights process may lead to the phenomenon of “imbalances” when evaluating the candidate solutions,through adjust the weight of each factor in the hope of the balance of various factors on the basis of variable weight theory.Secondly,sort of close to ideal solution method through TOPSIS method to obtain superiority degree from different candidates.Finally,a concentration equipment selection in an iron mine in Hebei Province was taking as an example,put forward three proposals which are horizontal sand bin,vertical sand bin and deep cone thickener respectively.Through calculation,the superiority degree of each scheme were 57.5%,72.1% and 88.5%,respectively,deep cone thickener is selected and the result is consistent with the engineering practice.It shows that the comprehensive evaluation index for the choice of backfilling concentration equipment has reference value,and it provides a scientific and reliable analysis method on the optimization problems in engineering practice.
Microseismic events arrival-pick is important for events location and other research analysis.Traditional method picked all collected signals and recognized the microseismic events manually,was not only heavy workload,but also low efficiency.This paper proposed an automatic method of recognizing the efficient microseismic signals,EEV(Energy Extreme Value).Calculated the ratio of the energy value between front and rear window through the specified moving time window,analyzed the different signals characteristics,put forward a method,through finding extreme value point,which the deviation between the right point is greater than the threshold diff,as the discrimination standard.Meanwhile,studied the main influence factors of this method, namely,the length of time window M,and the threshold diff,optimized and determined the optimal parameters. Using MATLAB Software to process the real datas of Dongguashan copper mine,the results show that the algorithm can accurately recognize nosie and seismic signal,the accuracy rate is up to 96%,compared with manual results,greatly shortens the time of data processing and improves the work efficiency,meanwhile, provide an important guidance for seismic signal process.
By using RMT-150C rock mechanics test system and PCI-2 type acoustic emission acquisition system,the acoustic emission characteristics of rock under different amplitude cyclic loading during complete damage failure process under uniaxial compression were studied to pure tailings backfill and ballast as filling aggregate.Experimental results show that acoustic emission signal of ballast cemented backfilling body is more abundant than pure tailing filling body under the cyclic loading damage failure process,and it is shown that the acoustic emission activity is most quiet in the stage of loading and unloading stress amplitude is 80%.At the same time,the experimental results show that the effective stress range of filling body Kaiser effect is lower than 70%,when the stress is higher than this,the Kaiser effect is invalid,and the Felicity effect is significant.
In order to accurately evaluate stability of mine goafs and analyze its main influential factors,according to the preliminary test data of goafs roof subsidence displacement,combination forecasting was applied to compose final predictive values of roof subsidence displacement by vary models,and then goafs stability was judged by resultant predictive values.Goafs stability was set as decision attribute,and its influential factors were set as condition attributes,variable precision rough fuzzy set was applied to probabilistically decision analyze assessment knowledge system of goafs stability,and 13 β- decision rules which β was 70% were got. It shows that goaf area,crustal stress size and temporary support way are decisive factors to goafs stability,and the classification quality of probabilistic decision rules is 62.96%,it is high,which can be references for stability judge and its law analysis.
Calculation of earthwork is one of the most important aspects of earth and rock engineering.In order to correctly use the methods to calculate earthwork and improve the accuracy of calculation,the basic principle of four different calculation methods in the DIMINE was studied.Combining with different engineering cases,the calculation results of the four methods were separately compared and analyzed by regarding the corresponding Boolean volume as the standard,and the error of each calculation method and the adaptability to data with different characteristics were discussed.The results show that there is different calculation accuracy for different method owing to the influence of the original data of landform characteristics,terrain change trend and slope variation.According to the basic principle of each calculation method and the error analysis of the experimental results,the corresponding suggestions were put forward aiming at the problems of application of the methods to calculate earthwork under the conditions of data with different characteristics,it provide reference to calculate earthwork with DIMINE correctly.
Aiming at the problems of low grinding production capacity,low efficiency of mill,low classigication efficiency of cyclone,high consumption of steel ball and energy,grinding research and industrial applications were carried out in Dayingezhuang gold mine,by using the technology of accurate ball loading and addition,and a good effect of increasing production and reducing consumption was achieved.The results show that the production capacity of the mill increased by 5.01%,electricity consumption decreased by 7.88% and the grinding media consumption decreased by 6.84%.Mill efficiency increased by 9.16% and 10.45%,respectively.Cyclone classification efficiency has been increased by 4.94% and 4.07%,the mass transfer efficiency of cyclone classifier increased by 3.51% and 3.90% respectively.The -0.074 mm product of cyclone classification increased by 0.52%,-0.010 mm content reduced by 3.5%.Concentrate grade and recovery has been improved.The results indicated that the increasing production of mill has a remarkable economic benefit,so it has the value of popularization and application.