【作者】 吴丽荣；

【导师】 周四春；

【作者基本信息】 成都理工大学 ， 核技术及应用， 2011， 硕士

【摘要】 马脑壳金矿是川西北著名的大型国有金矿山,经过多年规模开采,资源已经面临枯竭,为此,近几年来一直在矿区及外围开展接替资源找矿工作。由于马脑壳金矿区位于川西北高原,属于高寒地带,野外可工作时间短,加上矿区地形陡峭,植被覆盖广泛,缺少直接找矿标志,为开展找矿工作增加了难度,对此迫切需要一种适用于该地区的科学有效的找矿模式。本论文以国家危机矿山办项目“四川省九寨沟马脑壳金矿接替资源勘查（项目编号:200651094）”子课题“马脑壳金矿青山梁地区找矿靶区快速评价”为依托,针对马脑壳及外围金矿快速找矿为目标,选择马脑壳外围青山梁地区为研究区,开展了基于多种核地球物理方法的金矿找矿模式研究及找矿应用。马脑壳金矿为卡林型金矿,位于松潘-甘孜褶皱系与秦岭褶皱系的结合部位的川、甘、陕金三角金成矿带内,属于我国两大巨型卡林型金矿带之一的陕、甘、川“西北金三角”金矿带。卡林型金矿又名微细浸染型金矿,产于沉积岩及浅变质沉积岩中,赋矿主岩主要为碎屑岩及碳酸盐岩;有一套中低温的矿物共生组合和围岩蚀变;金的粒度多为次显微—显微级;在成因上属浅成中低温热液（渗流热卤水）金矿床。这类金矿成矿物质主要来自围岩地层,岩浆流体参与了成矿作用,矿床为与岩浆活动有关的混合热液金矿床。这类矿床中金与砷、锑、汞等元素的组合关系是最常见的组合关系。根据卡林型金矿的地质特征与前期地质工作者对该区的实际找矿研究,总结出马脑壳地区的找矿标志主要包括:构造标志:主断裂旁侧的派生断裂和破碎带,特别是发生在软硬岩层间的走向断裂及破碎带是很好的找矿标志。这为开展壤中α测量提供了依据。围岩蚀变标志:褐铁矿化、绿泥石化、碳酸盐化、硅化、雄黄矿化、辉锑矿化发育的围岩及断裂带、破碎带是良好的找矿标志。这为开展γ能谱测量提供了依据。地化标志:与断裂及破碎带、热液脉有关的较好的地球化学异常,其规模大,强度高,浓集中心明显,浓度分带明显,金、砷、锑、汞组合好,是良好的找矿标志。这为开展X荧光测量提供了依据。考虑到马脑壳金矿床的矿物组合主要是微细浸染状硫化金属矿物,这类矿物在较高频率范围内具有良好的激发效率,这为开展偶极幅频激电工作提供了依据。再考虑到马脑壳及外围实际地形地貌条件恶劣,最终我们选择了壤中α测量、γ能谱测量、X荧光测量、偶极幅频激电测量4种物化探技术,构建成马脑壳地区金矿快速找矿技术。这些方法不但都满足测量实际要求,而且仪器轻便,所用各种仪器设备的整机重量都不超过8kg,方便于随身携带,这也保证了方法技术的可实施性。在青山梁4km2区域的现场测量中,根据马脑壳金矿受构造控制的特点,以控制工作区内北西-南东向控矿构造为目的,按大致垂直于构造,按200×20 m网格布设了15条测线,开展了同线共点的壤中α测量、γ能谱测量、X荧光测量。在捕获的异常区及其相邻区域,则将测网加密到100×10 m。在已知金矿上的可行性实验表明,金矿体上方As、Cu、Pb、Zn呈现异常,同时伴生有U、Th和土壤α异常。据此,在青山梁4km2区域对壤中α测量、γ能谱测量、X荧光测量资料进行整理,以As为主,圈定出有γ能谱与土壤α异常相伴的5个异常。异常编号分别记As₁～As₅。在捕获的X荧光异常区域,我们从东到西布设了Q9、Q11、Q15、Q19四条幅频激电剖面,其主要目的是解剖异常,获取地下100m深度范围内硫化金属矿物的分布信息,对异常的解释推断提供充足的资料。As₁号异常位于测区南部,起于19线之西,呈带状沿F3延伸,止于11号测线之西F8断层处,其他物化探方法与荧光测量元素在此处也均表现出异常,在加上前有地质队在青山梁通过山地工程揭露圈定的金矿体位于该异常的中段,且矿体与异常吻合良好,可以认定该异常为金矿异常无疑。As₂号异常位于测区南部,F8断层之东, 11～7号测线范围之间,通过布设横穿As₂号异常的幅频激电拟断面测量,发现该幅频激电异常的展布形态,与青山梁地区含矿层的倾伏方向一致,具有明显的As、Cu、Zn、Pb等元素的组合异常,在异常边缘有K的异常,采集了异常区土壤样品做金定量分析也均反映匹配,为此可以认定,As₂号异常区应该是青山梁地区第二个找矿靶位。对于As₃、As₄、As₅异常,其他物化探方法与荧光测量元素并没有表现出组合异常,加上与构造呈现的关联关系不明确,异常展布的形态也没有明显规律可循,因此判定为无实际找矿意义。综上所述,在马脑壳地区开展多参数核地球物理测量,即X荧光测量、γ能谱测量、壤中α测量并加以偶极幅频激电拟断面解剖,可以对矿区金矿靶区进行快速评价。而本论文捕获的As₁号异常区域和As₂异常区域应该是青山梁地区进一步找矿的有利靶区。更多还原

【Abstract】 MaNaoke mine is a famous gold skull large state-owned gold mine at northwest of Sichuan, after years of exploitation, resources have been exhausted quickly, so the work to finding replaced resources in the mining and external in recent years. As the MaNaoke is located in Sichuan Northestern areas, belonging to the alpine, only can working a short time in the field, steep terrain with mines, extensive vegetation, the lack of direct prospecting, so a scientific and effective prospecting model suitable for region’s is required imperious.The paper based on“The rapid evaluation of goldmine prospecting targets about MaNaoke（Project Number:200651094）”project, select MaNaoke region outside the study aera, for puepose that MaoNaoke region outside fast prospecting, Carried out geophysical methods based on multi-core model of the gold prospecting and exploration applications.MaNaoke mine belong to Carlin-type mine, located in Songpan - Ganzi fold system and the Qinling fold system of the binding site of the Sichuan, Gansu, Shaanxi and the Golden Triangle of gold mineralization belt, belonging to the two giant Carlin-type gold deposits in China with one of the Shaanxi, Gansu, Sichuan "Northwest Golden Triangle "Gold Belt. Carlin-type gold deposit, also known as micro-disseminated gold deposit, produced in the sedimentary rocks and metamorphosed sedimentary rocks, assigned miners are mainly clastic rocks and carbonate rocks; A low temperature mineral paragenesis and wall rock alteration; Gold mostly submicroscopic size–micro level; Is shallow on the causes of the low-temperature hydrothermal （hot brine flow） and gold deposit. Minerals such as gold mainly from the surrounding rock strata, magmatic fluids involved in mineralization, deposit is mixed with the magmatic activity hydrothermal gold deposit. Gold and arsenic, antimony, mercury and other elements of the combination of relations between the most common combination in Such deposits.According to the geological characteristics of Carlin-type gold deposits and former geologists prospecting in the area of practical research, summed up the prospecting area to lobby skull include:Construction signs: Derived fault and fracture zones flanking the main fault , especially in soft and hard rock to fracture and fragmentation between the belt is a good prospecting. That providing a basis forαmeasured in soil.Wall rock alteration signs: limonitization, chlorite, carbonate, silicide, realgar mineralization, stibnite mineralization and development of rock, fault and fracture zones are good prospectings. That providing a basis forγray spectrometry.Localization signs: faults and fracture zones are related to hydrothermal geochemical anomalies so better, and the large-scale, high strength, significant concentration center, with a clear concentration of points, gold, arsenic, antimony, mercury and a good combination is a good prospecting. That providing a basis for X ray fluorescence measuring.Taking into account the mineral composition is mainly disseminated fine metal sulfide minerals in MaNaoke region, such minerals have good excitation efficiency in the highter frequency range. That providing a basis for amplitude frequency induced dipole.Considering that the MaNaoke region under a bad condition such as topography, ultimately, we chose such four geophysical and geochemical techniques thatαmeasured in soil,γray spectrometry, X ray fluorescence measuring, amplitude frequency induced dipole. They are not only meeting the actual requirement, but also portable, the weight of all instruments and equipment are no more than 8kg, and easy to carrying, which also ensures the implementation of methods and techniques can be.Measurements at the scence, according to the work area controlled by structural feature of gold mine, in order to control the North West- South east of the ore-controlling structures, we laid out a total of 15 lateral line ofαmeasured in soil,γray spectrometry, X ray fluorescence measuring at roughly perpendicularto the structure, the measurement by 200×20 m grid in normal, encrypty grid to 100×10 m for the anormalies.Viability of the known experimental results show that gold and gold body above the As, Cu, Pb, Zn showed abnormalities, and associated with U, Th and soil anomalyα. Accordingly, in the Castle Peak area of the soil beam 4km2 measurement ofα,γray spectrometry, X ray fluorescence measuring finishing measurements to As-based, delineated with aγspectrum accompanied by soil anomaly 5αexception. Abnormal number denoted As₁ As₅.For X ray fluorescence measuring anomalous areas, We set up Q9, Q11, Q15, Q19 four banners frequency induced profile from the East to the West, that main purpose is explaining the abnormal, understanding the distribution of metal sulfide minerals under ground about 100m depth. Located in southern As₁ begins in the west of 19 line along the F3 extensions, ribbons confined to 11, to the west of measuring lines caused the F8, Other geophysical and geochemical prospecting method and fluorescence measuring element here also all represent abnormalities, and geological team veteran revealed gold orebodies tagged in this abnormal by mountain project in QingShanliang aera, orebody agreement with abnormal ore, we can maintain this abnormality for gold anomalies undoubtedly. As₂ is located in southern test area east of F8 faults,in the range of 11 7 measuring line, we found that the exhition situation of amplitude frequency stimulation electric abnormal consistent pour volts direction of ore-bearing layer in QingShanliang aera though laid profile of Amplitude frequency stimulation electric across As₂ aera, there As, Cu, Zn, Pb and other elements composite anomaly, we collected abnormality area soil samples do gold quantitative analysis also reflected abnormalities In exceptional margin K abnormalities, there we can maintain that As₂ area should be green agains t area the second ore-prospecting targets. For As₃, As₄, As₅ aera, Other geophysical and geochemical prospecting method and fluorescence measuring element and not show combination abnormalities and have notclear relationship with tectonic present, there were also no significant rules form abnormal exhibition, therefore we judge that there have no practical for As₃ ,As₄ ,As₅ aera.There we summary that the As₁ regional and As₂ regional have the actual prospecting significance throughαmeasured in soil,γray spectrometry, X ray fluorescence measuring and amplitude frequency induced dipole.更多还原