浅论砂金矿床形成的地质条件

叙述了外生条件下砂金的地球化学性质,搬运介质及动力条件对砂金矿形成的意义,构造条件与砂金矿床形成的关系,地貌条件对砂金矿床形成之影响,砂金的补给源条件,砂金矿保存条件。研究砂金矿床的形成规律及不同砂金矿床的成矿地质条件,对进一步寻找有价值的工业砂金矿体,扩大储量,具有十分重要的经济意义。同时砂金矿床的发现常可作为原生金矿的指示标志,故研究其成矿地质特征,又有重要的地质意义。     

辽宁东堡子次火山热液型金矿床的地质特征和成矿条件

东堡子金矿床赋存于远离火山喷发中心的哨子河火山－沉积盆地南缘粗面斑岩中,矿床的成因类型属于与碱性次火山岩有关的浅成低温热液硅化岩型金矿粗面斑岩中成矿前北东－东西断裂破碎带为矿化蚀变带的形成奠定了构造基础．成矿前及成矿期节理裂隙系统在矿化蚀变带基础．上具体控制矿体的形成与分布．东堡子粗面斑岩即是成矿母岩又是矿体的围岩,粗面斑岩次火山期后热液和金矿流体,在粗面砂岩中形成蚀变和金矿化、金矿化与黄铁矿化、硅化及成矿期石英细网脉关系密切,特别是后者的发育程度具有决定性的作用．     

常宁大义山砂锡矿床形成的地质条件

通过对常宁大义山砂锡矿的调查研究，总结分析了常宁大义山砂锡矿形成的地质条件主要受构造条件和地貌条件的影响，提出了在大义山花岗岩体外围灰岩溶洞发现了一定规模的砂锡矿床，并初步分析了形成原因.     

Conditions for the Formation of Large High-Density Targets of High-Temperature Superconducting Materials

The properties of yttrium HTS powders obtained by solid-phase synthesis, a chemical method, and explosive compression were investigated. It is shown that the given methods of synthesis can be used to produce dense and highquality targets or other articles from HTS material. Powders with different physical and engineering properties, i.e. with different particle shape and size, flowability, compactibility and formability, are obtained by the different methods.     

Formation Mechanism of the Changxing Formation Gas Reservoir in the Yuanba Gas Field, Sichuan Basin, China

In a very gentle platform-margin paleogeographic environment, platform-margin reef flat facies carbonate reservoir rocks were developed in the Changxing Formation of Yuanba field. Later weak structural evolution and diagenetic evolution caused the Changxing Formation to form lithologic traps, with good reservoirs such as dissolved bioclastic dolostone and dissolved pore dolostone. The Changxing Formation gas reservoir is a pseudo-layered porous lithologic gas reservoir under pressure depletion drive, with high H2S and moderate Coz contents. This paper predictes that the conducting system for the Changxing Formation gas reservoir is possibly composed of the pores and microfractures in the Changxing Formation reservoir, the top erosional surface of the Changxing Formation, as well as the micropores and microfractures in the underlying formations. The Changxing Formation reservoir has experienced 3 hydrocarbon charging stages. This paper suggests that diffusion is the major formation mechanism for this gas reservoir. In the Middle and Late Yanshanian, the Yuanba area entered the major gas charging stage. The gas migrated mainly through diffusion and with the assistance of seepage flow in small faults and microfractures from the source rocks and the other oil-bearing strata to the Changxing Formation carbonate reservoir rocks, forming lithologic gas pools. In the Himalayan Epoch, the lithologic traps were uplifted as a whole without strong modification or overlapping, and were favorable for gas preservation.     

福建省大田县仙牛踏石锰矿区地质特征及其成矿规律初探

详细介绍了大田县仙牛踏石锰矿区的地质特征，包括地层、构造、岩浆岩、矿床特征，并对矿成矿规律进行了分析，这对该矿区地质找矿有实际意义。     

薄荷台-大榆树地区扶余油层成藏因素与有利油气富集区研究

研究区油气分布受构造、断层、沉积和油源等因素影响,造成油水关系复杂,油藏类型多样,给油藏评价和开发带来困难.薄荷台-大榆树地区扶余油层油气成藏受多种因素制约,对其成藏主控因素的分析是下步油藏评价、油气开发突破的关键.着重分析油气成藏控制因素,建立油气成藏模式,总结油气富集规律,寻找有潜力的油气富集区块,为开发优选有利目标区打基础.研究结果表明,预测研究区存在2个构造和4个岩性有利油气聚集带.     

白银市区工程地质条件简述

通过对白银市区工程地质进行分区,评价各区地形地貌及岩土物理力学性质,对岩土工程勘察及施工进行指导作用。     

Field Investigation of Soil Heave by a Large Diameter Chilled Gas Pipeline Experiment, Fairbanks, Alaska

A large scale 105-m-long, 0.9-m-diam chilled pipeline experiment was conducted to assess the response of a production pipeline that transits between unfrozen (seasonally frozen) and permafrost soils in discontinuous permafrost regions. Thermal and heave characteristics of the experiment for a three-year monitoring period are reported. In response to the chilled pipeline, the progressive cooling patterns within the permafrost and unfrozen soils were different, resulting in the development of a thermal boundary at the transition zone between the two thermally different soils. The absolute maximum movement of pipeline was 0.197 m near the thermal boundary, resulting in a differential heave of 0.148 m. Three distinct heave phases were identified within the unfrozen soil. Phase 1 of the first 200 days related to penetration and heave above the groundwater table and was characterized by heave rates between 0.211 and 0.237 mm/day. Phase 2 resulted in increased ice segregation due to interaction of the freez-ing front with the groundwater table. This phase lasted from approximately day200 to day 500 and corresponded to a heave rate from 0.206 to 0.313 mm/day. Phase 3 was characterized by a further decrease in the heave rate to about 0.081 mm/day and lasted from approximately day 500 to day 1,056.     

黑龙江砂宝斯矿田三十二站金矿地质特征及区域成矿条件分析

三十二站金矿位于额尔古纳隆起的北东向端,上黑龙江断陷盆地的边缘,属砂宝斯矿田重要组成部分,成因类型为破碎蚀变岩型中低温热液型矿床。区内共发现7条矿化蚀变带,其内8条矿体,品位最高为4、88×10^-6,平均为1．49×10^-6,围岩蚀变以硅化、碳酸盐化、绢云母化等中-低温蚀变为主。区域上金矿化主要受穹隆构造控制,侏罗系陆相碎屑沉积岩提供了部分矿源,找矿标志明显。     

优化国有大中型企业的经营环境

本文针对我国国有大中型企业普遍存在的负担过重，经济效益欠佳，经营环境有待改善等问题进行剖析，提出优化企业经营环境建议。     

陕西丝毛岭-柴蚂金矿床地质特征及开采技术条件浅析

丝毛岭-柴蚂金矿床是受小脆-韧性剪切带控制的小型金矿床,全矿床金储量3.66 t,矿床分两个矿段,共11条金矿体(丝毛岭矿段3条矿体、柴蚂矿段8条矿体),但没有明显的主矿体。矿床品位低,平均仅2.61 g/t,单个矿体规模更小,厚度也小,平均厚度都在薄-极薄矿体之间,而且矿体分布分散,就矿床自身条件来说不利于开发利用。     

水文工程地质条件及渗漏措施分析

水文工程建设必须采取合适工程防渗施工技术,才能更好的适应当下的发展需求。基于此,文章主要对水文工程常见地质问题进行了详细分析,进而对水文工程防渗施工技术与防渗施工措施进行相关探讨,以期能够为提升水文工程的建设质量提供有效参考。