Geological Features And Peripheral Perspective Prediction Of The Gaoyan Manganese Deposit, Chongqing

Gao Yan manganese deposit is located in the central of east CTB phosphorus manganese ore belt.It has the largest natural resources in this is ore belt in Chongqing. CTB phosphorus manganese ore belt spread northwest from Shaanxi Mian Ning and Lueyang to the east to Gaokouguan in Chongqing.There are QuJiashan, Ma Liu, Tianba, Gao Yan, Xiuqi and other deposits distributed in this ore belt. According to geographical conditions the belt can be divided into East and West belt and the Gao Yan manganese deposit is the most representative in the east belt.The tectonic location of Gao Yan manganese deposit in Chengkou thrust belt, the passive fold belts of Qin Qikun orogenic belt and Yangtze block. Investigation work zone belongs to IV Chengkou-Dongan manganese zinc phosphate ore belt (Ⅳ-2) and V level Gao Yan-Dongan manganese, lead, zinc, phosphorus ore belt (Ⅴ-2-1)CTB phosphorus ore belt are distributed all sedimentary rocks. They are Mingyue Group and Guanyinya Group of Pt3and Z, ε,strata.Gao Yan manganese deposit is located in a narrow Paleozoic massif between the Wulong-Pingba fault belt which belongs to the frontal imbricated fault fold belt of norther Daba Mountain nappe structure. The geology tectonic is extremely complex consist by a series of linear fold and thrust nappe fault form double fold.The work ledge of ore-bearing horizon is Z1d2which is a set of tidal-flat facies-stranded bay facies sedimentation and the lithology is mainly composed of interbedded sandstone, shale, black carbonaceous shale, ore layer. Ore bodies developed in the the top of Doushantuo Formation (Z1d) Which is shallow sea facies sedimentary dialogite deposits and the ore body in the stratified or stratoid, stable but often repeat or lost because of faults. Ore body from top to bottom can be divided into5layers, wherein the5-2layers is main ore and1layer is inferior ore. The thickness of main ore seam is0.1 -3.34m.The main component of primary ore is the rhodochrosite. The grade of Mn is18-23%for general and the highest grade is27.25%the20.53%for average. P/Mn is0.007-0.015%and the highest grade is0.0294, the lowest is0.0023.ore section average is0.0107. SiO2content is from30.55%to6.47%and is18-22%in general, the average is21.18%. Iron content is low, only from0.92%to3.34%. The structure of ore is spherules, fine-powder and the formation is massive, banded, stripped and stratiformstromato. Gao Yan Mn deposit belongs to the typical sedimentary manganese deposits.CTB manganese ore belt located in the eastern segment of the Qin Ba manganese deposition basin which is a north west-south east narrow asymmetric half-graben rift basin developed from passive continental margin rift system in Daba Mountain graben in Pt3. sedimentary center of the basin sedimentary center is in the west of Chengkou and manganese period appears in the Sinian sedimentary sequence most sea flood period (CS)--the top of Doushantuo Formation. The late Doushantuo, because the sea water intrusion, from Chengkou area to Zhenba is stagnant Bay which acceptance of a set of bay is manganese, phosphorus deposition. According to facies markers and other characteristics in spatial distribution, the city area is divided into the Gulf water rhodochrosite, phosphate rock, shale or dolomi.te phase (phase transition), the bay with stagnant carbonaceous shale rhodochrosite phase (Center) with three phases, in which manganese is mainly produced in the center phase transition phase, manganese ore was formed in weak reducing environment..(Z1d2)The Chengkou area manganese ore distribution has obvious stratabound features, without exception, are distributed in the lower Sinian Doushantuo Formation (Z1d2) formation. The ore body thickness changes in general is relatively stable, but the manganese formation (Z,d2) varying greatly in the thickness, and the ore body thickness variation correlation is not obvious. This shows that in the Doushantuo stage, retention basin topography in the ore deposition is a rugged. Types of sedimentary formation in the region is relatively stable, on the whole are for containing manganese and phosphorus rock formation, but its lithology combination and exists in2forms: black carbonaceous shale (bottom)+Mn ore siderite clip phosphorus strip, carbonaceous shale interbedded+dolomite (top) combination, or black carbon shale (bottom)+phosphate rock, rhodochrosite interbedded+dolomite (top), the former Gao Yan manganese deposit as the representative, the latter to the Dadu River manganese deposit as representative.Sichuan Provincial Institute of Geological Survey through the research area of water stream sediment anomaly characteristics outlined2geochemical assemblage anomaly. The district has found the manganese deposits are located in the geochemical assemblage anomaly band and the inner band.The authors evaluate the CTB P manganese ore zone outlined14minimum prediction unit on the comprehensive analysis of previous research results and data, summed up area of manganese ore prediction factor conditions, according to the analogy principle, using Mn-bearing sequence distribution range, the ore-bearing rock series construction characteristics, characteristics of ore deposit, geochemical assemblage anomaly, paleogeographic characteristics and other factors. The volume was obtained by the method of resource of72079900tons, which has proven reserves of36544200tons, is the potential resource of35535700tons.The paper combined with the ore-forming conditions, ore formation characteristics, deposit feature, social and economic benefits and other factors optimized and grading the14minimum prediction unit The Chengkou region of the manganese ore prospecting target area is divided into3grade predicted area and3grade Ⅱ forecast area, are Gao Yan-ShangshanPing predicting area (I1), Daduxi forecast area (I2), Xiuqi forecasting area (I3), Chen Bay-Gaoliangping forecast zone (Ⅱ1) Mingyue-Tianwan predicting area (Ⅱ2), Baojiashan prediction area (Ⅱ3), and has carried on the geological evaluation, points out the first5prediction in greater prospecting potential in which the Baojiashan prediction prospecting potential is smaller.