Application of geophysical and geochemical exploration results in. Prospecting prediction:taking Pangjiagou-xiajinbaogou Au-Ag

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1 Advanced Materials Research Online: ISSN: , Vols , pp doi: / Trans Tech Publications, Switzerland Application of geophysical and geochemical exploration results in Prospecting prediction:taking Pangjiagou-xiajinbaogou Au-Ag polymetallic ore in Hebei Chengde as an example Dong Wang 1, Yong Feng Yan 1 and Jiao Jiao Chen 1 1 Faculty of Land Resource Engineering,Kunming University of Science and Technology,Kunming,China First Author:Dong Wang, @qq.com Corresponding Author:Yong Feng Yan, yyf701018@vip.sina.com Key words: Metallogenic prediction; Prospecting targets ;Polarizability Abstract. Pangjiagou-xiajinbaogou Au-Ag polymetallic ore in Hebei Chengde magmatic activity is very strong, mainly Late Jurassic - Early Cretaceous of granite and Late Yanshanian alteration of acidic rocks, archean metamorphic rocks and Middle Proterozoic strata containing mainly gold seam. Studies show that the area is insignificant on main rock resistivity, and all kinds of mineral body, mineralized rocks Fs> 2.4%, gneiss containing high gold abundance, gold body, auriferous quartz veins are greater than 2.4% Fs,can be used as an indirect sign on geophysical prospecting. Sb, As, Pb, Ag, Au and other elements of the exception can be used as indirect signs on geochemical prospecting. After considering this area geophysical, geochemical characteristics analysis of, binding studies geological conditions, prospecting method using the analogy prediction target region, the success of the orebody found. Introduction Geologic conditions are relatively complicated and complex ore types, there have been 514 teams Chengde, Beijing Geological Survey and many other units in the area to work, but failed to find mine. Based on the field survey, and combination of geological conditions, the area geophysical and geochemical exploration work carried out analysis, thus performed better target prediction and engineering verification, and achieved breakthroughs in prospecting. Geological Background Area in the middle of the North China Craton silver-gold deposit concentration areas in northern Hebei, the north of Chifeng silver polymetallic deposit concentration areas. Membership on the area during tectonic North China Platform of Inner Mongolia Axis and Yanshan fold belt, belongs to North China Craton polymetallic metallogenic belt. Currently found in ore and mineralization nearly one hundred, large Cu-Mo deposit with one(xiaosigou Cu - Mo deposit), and more than 10 small and medium sized deposits. Mineralization type is more complex, mainly hydrothermal (fissure filling) type. Gold-bearing polymetallic ore, lead and zinc containing silver, lead and zinc, copper, gold-bearing quartz veins, hydrothermal metasomatic lead-zinc and porphyry copper-molybdenum mine, are mainly formed in the Archean, Mesozoic Jurassic Jurassic. Geological Characteristics The main study area outcropping strata Sinian Great Wall Group set paralic pebbly sandstone, quartz sandstone, shale. Were Gaoyu group of three sections (Z1g3), Gaoyu group Sec (Z1g2), Dahongta group (Z1d), Tuanshanzi group (Z1t), Banlinggou group (Z1ch), Changzhougou group All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-09/05/16,02:45:41)

2 Advanced Materials Research Vols (Z1c3), Dahongta group and Gaoyu group of which is the main group with seam. Gaoyu group mainly composed of dolomitic limestone, manganese dolomite, manganese shale, quartz sandstone; Dahongta Group mainly composed by quartzite, shale. Metallogenic obviously controlled by structure, NE-trending faults of F1 is pressed torsion fracture, F1 and NW-trending faults intersect in the south, the formation and development of F1 is not only control the gold-bearing porphyry magma activities, and controls the output of the orebody. Mining area development annular configuration control of the ore-related gold-bearing porphyry intrusion. F1 intersection with it, rocks are mainly granite porphyry, quartz monzonite porphyry, rhyolite porphyry, diorite and diorite. In the ore-controlling fault zone near ubiquitous pyrite and gold mineralization and to develop a set of gold-bearing quartz veinlets, miscellaneous porphyry and older formations (mainly Dahongyu group and Gaoyuzhuang group Formation of Changcheng System) contact with broken alteration zone, contact with broken Bandwidth meters range, the overall curved Spread, from north to south by the move towards north-south, west steeply dipping into the North East to move towards east-west, northward dipping. Contact with broken rock band includes rock alteration zone in vivo exposure and outer contact alteration zone, contact fracture zone exists in a group of ring-shaped fracture with radial fracture staggered, it is the main bonanza tectonic of Lead, gold multi-polymetallic mineralization. The region intrusive bodies of related to mineralization is granitic porphyry, gold mineralization is mainly produced in altered granitic porphyry in the upper, show disseminated - veinlets distribution; gold-iron mineralization and a small amount of lead-zinc-silver mineralization mainly in rock and thin limestone of Gaoyuzhuang outside the contact zone and interlayer fracture zone, NEE wavy curved toward soothing distribution. Geophysical and Geochemical Anomalies The Physical Characteristics of Rock (ore) Stone. The resistivity of the major rock is insignificant, a difference of less than a grade of. The amplitude frequency Fs of andesite, diorite, clay dolomites is 0.5 to 0.9 percent, is the normal low background value; secondary quartz trachyandesite porphyry, clay of intrusive breccia, intrusive breccia, quartz sandstone, mineralized quartz sandstone of amplitude frequency is between 1.6 to 1.8 percent, in the survey area as normal background values, where intrusive breccia, quartz sandstone if have Pyritization, there is a higher frequency of abnormal reflection amplitude; mixed breccia, quartz syenite porphyry, diorite, quartz porphyry, feldspar porphyry, granite porphyry, quartz monzonite porphyry, dolomite, amplitude frequency between 1.2 to 1.5 percent, in the normal course of the survey area; limonitization intrusive breccia, altered granite porphyry, limonite monzonite porphyry, limonite dolomite, pyrite and other minerals phyllic body and mineralized rocks (including symbiosis whis pyrite, chalcopyrite, limonite, hematite, galena, sphalerite), a higher degree of mineralization, amplitude frequency at 2.4%, is the basis for the region delineated exceptions; gneiss amplitude frequency of 2.7%, because hornblende mineral content is high in the rock, and uneven, especially gneiss containing Haven value high, close to the tectonic fissures, gold or gold-bearing ore body quartz veins (ore) Lot amplitude distribution showed a higher frequency of abnormalities, and varied greatly(is shown in Table.1).

3 2194 Environmental Protection and Resources Exploitation Table.1.Mine electrical parameter measurement statistical results table Rock name ρs (Ω.m) Fs (%) Range Mean Range Mean Quaternary 33~ ~ Gneiss 150~ ~ Mixed breccia 1499~ ~ Quartz syenite porphyry 600~ ~ Diorite 47~ ~ Diorite 146~ ~ Quartz porphyry 354~ ~ Intrusive breccia 110~ ~ Andesite 58~ ~ Granite porphyry 151~ ~ Altered granite porphyry 230~ ~ Dolomite 130~ ~ Clay dolomites 38~ ~ Quartz sandstone 74~ ~ Pyrite phyllic 47~ ~ Polarization Anomaly Analysis. IP-1 IP anomalies: Abnormalities are zonal, the overall trend in NW-trending, length 2000 m, width of 500 to 800 meters, abnormal located both inside and outside the contact zone of inferred magnetic circular structures (concealed rock), ie F1 fracture intersections with circular structure, anomalies in the plane is made up of multiple Fs is greater than 4.1% and resistivity anomaly of less than 600 ohms, abnormality accompanied AU soil geochemical anomalies and Pb, Zn, Ag, Cu, Mo composite anomaly H-1, more favorable metallogenic conditions(is shown in Fig.1). Fig.1.Intermediate gradient anomalies plan IP-2 IP anomalies: Abnormalities are zonal, nearly east-west, about 500 meters wide and 100 to 200 m, abnormal located the northwest corner both inside and outside the contact zone of inferred magnetic circular structures, abnormal strictly controlled by F1, abnormality accompanied AU soil geochemical anomalies and Pb, Zn, Ag, Cu, Mo composite anomaly H-1, more favorable metallogenic conditions.

4 Advanced Materials Research Vols IP-3 IP anomalies: Abnormalities are zonal, to the north west, the abnormal area is small but the strength is strong, Fs maxima MaxFs is 13.4%, abnormal in the intersections of F3 and F4, more favorable metallogenic conditions. In summary, in this region geophysical anomaly exhibition cloth is a near Pak the West direction, and east-west towards, abnormal were tested Ribbon, IP1, IP2 anomalies distribution porphyry inside and outside contact zone of rock mass both side, IP3 in F3 and F4 intersection area, Distribution of siltstone, shale. Geochemical Anomaly Characteristics. Migration and enrichment of elements can form regional or local anomalies, the abnormal characteristics and scale, is crucial to the evaluation of prospecting information. Analysis element anomaly characteristics, is significant to the study of metallogenic regularities and prospecting. Regional anomaly with Pb, zinc, Ag, Au, Sb, As, give priority to, by element anomaly map can be seen in the area is the largest range of Ag, followed by Pb, Au, zinc, Sb, a.s. Ag is in the north-south strip; Pb is northwest; Zinc, Au is planar and mixed cone ; Sb, As, more irregular ribbon;and both has a strong focus on the heart and tertiary anomaly concentration zoning characteristics. Most Pb, Zn abnormal morphology and concentration centers with Au are in good agreement,be looking for signs of gold, and is looking for gold in the deep foundation. By this measuring zone four comprehensive anomalies do Q-type cluster analysis, the four composite anomalies can be basically divided into two types. First class is H-5 comprehensive abnormalities, abnormal elements mainly Pb, Zn, Ag, Au, Sb is given priority to(is shown in Fig.3); The second category mainly for H-1, H-2,H-3 comprehensive anomaly and anomaly elements is given priority to with Mn, As, Sb, Ag(is shown in Fig.2). Fig.2.Mine comprehensive geochemical anomaly map measuring secondary halo (Mn As Sb Ag)

5 2196 Environmental Protection and Resources Exploitation Fig.3.Mine comprehensive geochemical anomaly map measuring secondary halo (Pb Zn Ag Au Mo) Conclusions Pb, Zn, Ag, As, Sb, Mo, Au, etc element has the feature of regional relative enrichment, uneven regional distribution, enrichment of state formation in a local location for late enrichment provides the source of ore-forming materials. Obvious physical differences between surrounding rock and orebody, Fs is greater than 2.4%. As an important geophysical prospecting indirect signs. Au, Pb, Zn composite anomalies in the study area can be used as an important geochemical indirect ore-prospecting criteria. Comprehensive research, sort out geological data, geophysical and geochemical prospecting information, determine the prospecting target area, for project validation, is an effective method of prospecting for success in this area. References [1] Yuanjiao Dong,Rongquan Wang,etal.Report on silver polymetallic ore exploration of Pangjiagou in Chengde Liangjiaxiang, Hebei Province[R]. North China Geological Exploration Bureau comprehensive survey brigade record room,1994.(in Chinese) [2] Rongquan Wang,Zhiliang Ge, etal. Geological characteristics of Pangjiagou silver poly metallic deposit anditsgenesis[j]. Mineral Resources and Geology, 2007,21(3): (In Chinese) [3] Yang Fu,JianXin Wang, etal. Application of geophysical and geochemical exploration results in predicting Prospecting target:taking Jinchanggou Cu-Mo-Au deposit in Jidong as an example[j].global Geology, 2010,29(2): (In Chinese) [4] Shaohui Lv,Sichun Zhou, etal. Research on Integrated Geophysical and Geochemical Prospecting Thought and Prediction of Prospecting For The KLM Gold Mine[R]. Metal Mines,2010. (In Chinese)

6 Environmental Protection and Resources Exploitation / Application of Geophysical and Geochemical Exploration Results in Prospecting Prediction: Taking Pangjiagou-Xiajinbaogou Au-Ag Polymetallic Ore in Hebei Chengde as an Example /