Geological Characteristics and Ore-controlling Factors of the Beiya Gold–Polymetallic Ore Deposit, Northwestern Yunnan Province

Based on comprehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the source（s） and evolution of magmas. Our results suggest that syenite porphyries（i.e. the Wandongshan, the Dashadi, and the Hongnitang porphyries）, which formed between the Eocene and the early Oligocene epochs, are the sources for the gold-polymetallic ores at the Beiya deposit. Carbonate rocks（T2 b） of the Triassic Beiya Formation in the ore district provide favorable host space for deposit formation. Fold and fault structures collectively play an important role in ore formation. The contact zone between the porphyries and carbonates, the structurally fractured zone of carbonate and clastic rocks, and the zone with well-developed fractures are the ideal locations for ore bodies. Four types of mineralization have been recognized： 1） porphyry-style stockwork gold–iron（copper） ore, 2） skarn-style gold-iron（copper and lead） ore in the near contact zone, 3） strata-bound, lense-type lead–silver–gold ore in the outer contact zone, and 4） distal vein-type gold–lead–silver ore. Supergene processes led to the formation of oxide ore, such as the weathered and accumulated gold–iron ore, the strata-bound fracture oxide ore, and the structure-controlled vein-type ore. Most of these ore deposits are distributed along the axis of the depressed basin, with the hypogene ore controlling the shape and characteristics of the oxide ore. This study provides critical geology understanding for mineral prospecting scenarios.

Quantitative analysis of geological ore-controlling factors and stereoscopic quantitative prediction of concealed ore bodies

To address the issues for assessing and prospecting the replaceable resource of crisis mines, a geological ore-controlling field model and a mineralization distribution field model were proposed from the viewpoint of field analysis. By dint of solving the field models through transferring the continuous models into the discrete ones, the relationship between the geological ore-controlling effect field and the mineralization distribution field was analyzed, and the quantitative and located parameters were extracted for describing the geological factors controlling mineralization enrichment. The method was applied to the 3-dimensional localization and quantitative prediction for concealed ore bodies in the depths and margins of the Daehang mine in Guangxi, China, and the 3-dimensional distribution models of mineralization indexes and ore-controlling factors such as magmatic rocks, strata, faults, lithology and folds were built. With the methods of statistical analysis and the non-linear programming, the quantitative index set of the geological ore-controlling factors was obtained. In addition, the stereoscopic located and quantitative prediction models were set up by exploring the relationship between the mineralization indexes and the geological ore-controlling factors. So far, some concealed ore bodies with the resource volume of a medium-sized mineral deposit are found in the deep parts of the Dachang Mine by means of the deep prospecting drills following the prediction results, from which the effectiveness of the predication models and results is proved.

The Characteristics of Ore-Controlling Structure in Baoshan Cu-Pb-Zn Polymetallic Deposit,Hunan Province

The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian.

Mineralization and Ore-controlling Implications of Low-angle Faults

Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and replace the tectonites in the fault zone. The rocks of the hanging side and the heading side differ in lithology, texture and structure, which results in changes or dissimilarities of the physical-chemical conditions. This destroys the balance of the hydrothermal solution system and causes the dissolved ore-forming elements to precipitate; as a result, a deposit is formed. Therefore, the meso-shallow ductile-brittle low-angle faults play the role of a geochemical interface in the process of mineralization. (3) Low-angle faults are often one of the important host structures.

Analysis of Ore-controlling Structure in the Qifengcha-Detiangou Gold Deposit,Huairou County,Beijing

The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshanian magmatic activity. Characterized by multiperiodic activity, the NE-trending Qifengcha fault is a regional ore-controlling structure in the area, and gold mineralization develops only in its southeastern part. Meanwhile, gold mineralization is controlled by the Yunmengshan metamorphic core complex. The nearly N-S- and E-W-trending low-angle detachment faults, reformed by the Qifengcha fault in the northwestern part of the core complex, are the main ore-bearing faults. All discovered gold deposits are located within an area 1.5–4.0 km away from the boundary of the upwelling centre. The N-S- (NNE-) and E-W-trending ore-bearing faults are ductile-brittle structural zones developing in shallow positions and subjected mainly to compressive deformation. The structural ore-controlling effects are as follows. (1) The attitude, shape, and distribution of gold orebodies are controlled by faults. (2) There is a negative correlation between the gold abundance and the magnetic anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is later than the structural deformation. (3) Quartz vein type mineralization is superimposed on altered mylonite type mineralization. (4) In mineralized mylonite, the stronger the ductile shear deformation, the easier the late-stage gold mineralization to occur and the higher the gold abundance. The richest gold mineralization occurs only around the centre of the fault subjected to the strongest deformation.

Geophysical Features of the Ore-Controlling Fault in the Chang'an Gold Deposit, Southern Yunnan Province

The Ailao Mountain is one of the most important metallogenic belts ofpolymetallic deposits in the Sanjiang region, southwestern China. Located in the southern segment of this metallogenic belt, the newly-discovered Chang＇an gold deposit is large in scale （Fig. 1A）, and has attracted much attention among geologists. The ore-hosted rocks in the district include the Late Ordovician Xiangyang Fm. sandstone and clastic rocks and the Early Silurian Kanglang Fm. dolomite. Affected by the multistage tectonic activities, stocks and dykes of lamprophyre, dolerite, syenite porphyry and orthoclasite are widely exposed, and the orebodies are in symbiosis with or crosscut the dyke rocks.

Analysis of Ore-Controlling Structures of the Xincheng-Hexi Gold Deposit,Shandong Province,China

Based on quantitative and semi-quantitative mathematical and mechanical analysis of the shape, motion, structural factors, stress field and deformation field of the ore-hosting faults in the Xincheng-Hexi gold deposit, the ore-controlling features of faults and mineralization mechanism are discussed. It is concluded that the mineralization is controlled by the main faults, subsidiary fractures, joint density, mechanical features and deformation of the faults. The ore bodies are mainly located in the lower part of the convex crest and upper part of the concave trough of the main undulating fault surface. Mineralization is positively correlated to the development of subsidiary fractures and joints, which correspond to zones of low internal stress and high body strain and shear strain. They are favourable positions for mineralization and alteration.

Ore-controlling Regularitiesof Structureinthe Lehong Lead-zinc Deposit, Northeastern Yunnan

1 Introduction The Lehonglead-zincdeposit is a large-sized Pb-Zn depositnewly found in recent years in the Sichuan-Yunnan-Guizhou Lead-zinc Poly-metallic Mineralization Area,which occurrenceis strictly

Ore-controlling Characteristics of Synchronous Faults of Dongshengmiao Polymetallic Sulfide Deposits in Inner Mongolia

1 Introduction The Dongshengmiao deposit is a super-large Zn-Pb polymetallic sulfide deposit which occurring in the Langshan-Zhaertaaishan metallogenic belt,and located in the western margin of the North China Platform.The ore-bodies of Dongshengmiao deposits are mainly hosted in the second Formation of Langshan Group.There are some studies on the geological characteristics(Peng et al.,2004),geological and

Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District

1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China.

GEOCHEMICAL REASERCH ON ORE-CONTROLLING STRUCTURE IN LIAODONG LUOQUANBEI-BAIYUN GOLD MINERAL BELT

In recent2 0 years,because of the finding ofmany large- superlargegold deposits,we re- new the theories for prospecting and gain many things and conceptions.The current geo- chemical and gold- forming theories underline the importance of the early submarine volcano- sedimentation,metamorphic differention,sedimentation of terrigenous clastics,thermal spring and it’s sedimentation,syngenesis process and other hypergene supplying the source for metallogenic materials.According to the study for source bed(rock) and depsitional for- mation of gold,we find that gold will be gradually enriched and mineralized in source bed (rock) ,because of variousgeologicprocesses,such as regional metamorphism ormigmatiza- tion,geothermal bittern,volcanism. The ore- control of deep and giant fault and ductile shear beltand tectono- flash space is emphasized,especially,we should notice the long- term, succession and multistage of the

海岛女性慢性宫颈炎患病率及其影响因素的调查研究

[目的]探讨海岛女性慢性宫颈炎患病率及其影响因素。[方法]采用统一调查表,对舟山市2854例女性进行流行病学问卷调查、妇科检查和实验室检查;并对数据进行统计学处理。[结果]研究对象慢性宫颈炎患病率达54.56%;其中,以宫颈糜烂位居第一位,患病率为36.37%;其次为宫颈肥大和纳氏囊肿,患病率分别为24.32%、21.06%;慢性宫颈炎的形成可能与年龄、文化程度、人流次数及引产次数等因素有关(P<0.05)。随着年龄的增长、人流次数与引产次数的增多,患慢性宫颈炎的危险性将增加;而文化程度愈高,患宫颈炎的可能性愈小。[结论]海岛女性慢性宫颈炎患病率较高。其中,宫颈糜烂、宫颈肥大患病率分别位居第一、第二位。宫颈炎的形成可能与年龄、文化程度、人流次数及引产次数等因素有关。

重症手足口病87例临床观察

目的总结小儿重症手足口病(HFMD)临床表现类型,探讨其早期高危因素。方法对87例小儿重症HFMD住院资料作回顾性总结。结果HFMD病重者87例合并神经系统损害者68例,占78.16%,合并神经系统损害为重症病人的主要表现,精神萎靡和肢体抖动、激惹往往是最初表现和最常见表现。合并循环系统损害者4例,占4.60%,合并持续高热15例(17.24%),重症肺炎3例(3.45%),急性肺水肿2例(2.30%),消化道出血4例(4.60%),明显腹胀3例(3.45%)。87例小儿平均月龄(19.43±3.61)个月,<3岁者69例,占79.31%,与对照组(36/103,34.95%)相比,差异有统计学意义(P<0.01);出现高血压者68例(78.16%);临床发现重症病例随机血糖增高,87例重症病儿平均血糖为(8.91±1.03)mmol/L,与对照组(5.12±1.14)mmol/L相比,差异有统计学意义(P<0.01);87例重症患儿平均周围血白细胞计数为(16.65±4.13)×109/L,与对照组(6.96±1.31)×109/L相比,差异有统计学意义(P<0.01);重症病例组共有79例(90.80%)血象升高,其中中性粒细胞比例同步升高者71例,与对照组22例(21.36%)白细胞升高相比差异有统计学意义(P<0.01)。87例小儿中具有典型疱疹者71例(81.61%),87例小儿经治疗后痊愈出院84例(96.55%),自动出院1例,死亡2例。本病的早期高危因素有:年龄、发病时间、发热、血压升高、血糖升高、血象升高等。结论重症HFMD合并神经系统损害较为常见,应高度关注早期高危因素,进行早期干预,提高救治效果。

功能性消化不良的精神心理因素分析

目的:研究讨论功能性消化不良(FD)和精神心理因素的关系。方法:选择符合标准的160例功能性消化不良患者和160例健康对照人员,使用汉密尔顿抑郁量表(HAMD)和汉密尔顿焦虑量表(HAMA)对其进行评估。结果:功能性消化不良组和健康对照组的HAMD评分、HAMA评分比较差异有统计学意义(P<0.05)。结论:功能性消化不良患者存在不同的精神和心理障碍。

PET固相缩聚反应的影响因素

PET的固相缩聚是将低分子量预聚体加热到熔点和玻璃化温度之间,切片内部缩聚反应持续进行,分子量不断提高,乙二醇、水等副产物借助真空或惰性气体带出反应器.固相缩聚中包括酯化反应、酯交换反应以及小分子的扩散过程.表现反应速率受预聚体颗粒形状大小、结晶度、惰性气体、反应温度、反应时间等因素的影响,其中反应温度、惰性气体中小分子副产物含量是两个主要影响因素,应合理选择并控制这些参数,以利于生产出高质量的PET.

动机视角下乡村旅游者主观幸福感的驱动机制研究——以皖南传统古村落为例

旅游者幸福感是促进旅游可持续发展的重要因素,因此对旅游者主观幸福感及其影响因素的研究,是值得关注的科学问题。文章以乡村旅游者为研究对象,将旅游动机的8个维度作为自变量,运用多变量交互作用的模糊集定性比较分析方法,探索影响乡村旅游者主观幸福感的复杂路径。结果显示:(1)在单因素分析中,所有单变量因素均不能构成乡村旅游者主观幸福感影响因素的充分必要条件;(2)8个条件变量共产生256条组合路径,满足条件的组合路径为9条,总体覆盖率为0.803,能够很好地解释结果变量;(3)在因素分析中原始覆盖率高于40%的组合路径均包括兴奋、家庭和乡愁这3个变量。文章为有效开发乡村旅游地及利用乡村旅游资源,提升人们的获得感与幸福感,促进乡村旅游高质量发展提供了理论依据。

湖北枣阳市乙肝患者对乙肝防治知识的认知情况及影响因素分析

目的观察湖北省枣阳市慢性乙型肝炎患者对疾病防治知识的认知情况及影响因素。方法回顾性分析湖北省枣阳市疾病预防控制中心收治的182例慢性乙型肝炎患者的临床资料,患者均采用问卷调查的方式进行,采用自行研究设计的一般情况与疾病防治知识认知情况调查表进行,并采用多因素Logistic回归其影响因素。结果182例患者疾病防治知识知晓率为72.53%;其中知晓率最低分别是发病机制、不良预防行为的危害及预防目的,知晓率均<70%。知晓组与不知晓组在年龄、居住地、家庭收入、文化程度、病程4个变量差异有统计学意义(P<0.05)。年龄、家庭收入、文化程度差异有统计学意义(P<0.05)。年龄、家庭收入、文化程度均是影响慢性乙型肝炎患者疾病防治知识认知程度的危险因素。结论慢性乙型肝炎患者对疾病防治知识的知晓率为72.53%,其影响因素主要包括年龄、家庭收入、文化程度,医护人员应严格掌握其影响因素,早期加强对乙肝防治的宣传教育,从而有效提高慢性乙型肝炎患者的预后生存质量。

The Formation of the Jiaodong Gold Province

Gold deposits in Jiaodong,termed Jiaodong-type,are tectonically located in the southeastern margin of the North China Craton.Their major features are reviewed in this paper to highlight the differences between Jiaodong deposits and other genetic types of gold deposits.The mineralization was synchronized with asthenosphere upwelling indicated by synore OIB-like mafic dike and large-scale crustal thinning suggested by decrease of Sr/Y from pre-ore to syn-ore granites.Asthenosphere upwelling induced by the roll-back of Paleo-Pacific Plate drove partial melting of lithospheric mantle and devolatilization,which induced the release of the ore-forming fluids.In concomitant with magmatic records,mineralization migrated from the western Jiaobei terrane(133–127 Ma)to the eastern Sulu orogenic belt(114–108 Ma),corresponding to the eastward roll-back of Paleo-Pacific Plate.Gold mineralization in Jiaodong formed in the transitions of ductile to brittle deformation,rapid to slow crustal uplift,and regional compression to extension.In the regional-scale,the gold deposits in the Jiaobei terrane are mostly situated at intersections between NE-trending faults and EW-trending basement faults,and gold orebodies dominantly controlled by the lithologic contacts between Precambrian metamorphic rocks and Mesozoic granites.The mineralization was dominated by the disseminated-veinlet ores related to quartz–sericite alteration in strong cataclasite-breccia zone,with subsidiary thick quartz-sulfide veins developed in secondary fault zones.The ore-forming fluids belong to a H_(2)O–CO_(2)–NaCl±CH_(4)system and show minor variations in salinity among different types of ore.Structure-fluid feedback involving fluid-rock reaction and hydrofracturing triggered the fluid phase separation and resultant gold deposition.The Jiaodong gold deposits are distinct from orogenic and intrusion-related gold deposits in terms of tectonic setting,origin of ore-forming fluids,and mechanism of gold deposition.