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1.
柴达木低品位固体钾矿溶解转化率与品位关系   总被引:1,自引:1,他引:0       下载免费PDF全文
我国是缺钾大国,探明的可溶性钾盐十分有限,柴达木盆地是我国盐湖钾盐的聚集地,含水层骨架中含有数亿吨低品位固体钾矿,开发出这些低品位固体钾盐对增加国内钾肥供给,保障粮食安全具有重大意义。青海盐湖工业股份有限公司历经十年开发出低品位固体钾盐的浸泡式溶解转化方法,试验表明,固体钾盐的溶解转化率随固体钾品位的增加而增加,累计溶解转化率为56%~98%。该技术在柴达木多个盐湖得到推广应用,察尔汗盐湖保有固体钾盐达2.96×10~8 t,平均品位KCl为1.24%,根据试验数据回归分析溶解转化率77%,可溶解转化出钾盐(KCl)约2.28×10~8 t,柴达木盆地盐湖保有3.43×10~8 t固体钾盐,平均品位KCl为1.25%,溶解转化率78%,可溶解转化出钾盐(KCl)2.68×10~8 t,大幅度增加了钾盐储备量。  相似文献   
2.
根据盐类矿层分布特征,布谷马西钾盐矿床以奎卢河为界可分为南部、北部2个矿段,通过二维地震勘探、钻探、岩矿测试等技术手段对2个矿段进行了较详细勘查,根据对2个矿段的沉积特征、岩性及二维地震特征对比分析,2个矿段虽然同处于刚果盆地内,但沉积特征存在一定差异,南部矿段矿层沉积较稳定,北部矿段受断裂构造影响,盐类沉积上部多发育裂隙、溶蚀、塌陷等,导致北部矿段Ⅲ,Ⅳ岩性段出现沉积缺失。  相似文献   
3.
Extensive potassium and phosphorous-rich mineralization occurs on the outer continental shelf of the southern and west coasts of South Africa and Nambia. This article reviews the potential of exploiting these deposits in an environmentally sound manner for the manufacture of fertilizer. At present, reserves of potash and phosphate fertilizer are exploited from terresterial deposits, the majority being surface mined. The use of fertilizer in South Africa has shown no growth in the past 13 years, and, in some years, usage has even declined. On average, over the last decade, South Africa has consumed 2 million Mt of fertilizer (including nitrogen) per annum, the vast majority of phosphate fertilizer being produced by FOSKOR from the Phalaborwa Igneous Complex. Potash fertilizer is imported into South Africa. Although fertilizer consumption is expected to decrease in the short-term, there are good future prospects for the domestic and international fertilizer market. Considerable research into both glauconitic (containing K 2 O) and phosphatic deposits along the southern African continental shelf indicate that these sedimentary deposits have a complex genesis and mineralization. Of the total K 2 O reserves of 1300 million Mt on the southern African margin, 1000 million Mt is located off the southern African west coast, and the remainder situated on the Agulhas Bank. The largest glauconite concentration ( - 300 million Mt K 2 O) off southern Africa lies west of Saldanha Bay, South Africa. The distribution of P 2 O 5 off southern Africa is dominated by the vast deposit between Walvis Bay and Luderitz, Nambia. This reserve is estimated to contain 1000 million Mt of greater than 5% P 2 O 5 in a relatively small area of about 10000 km2. The phosphorite deposit south of Saldanha Bay constitutes a reserve of - 3500 million Mt of apatite and the deposit on the Agulhas Bank comprises 5500 million Mt. The phosphate deposit off Saldanha Bay occurs as an extensive, low to medium grade deposit. Although vast resources of potash and phosphatic minerals occur along the southern African outer continental shelf the expensive nature of marine exploitation may render most of these deposits, especially the phosphates, subeconomic. The low price of fertilizer andextensive natureontheonland deposits, although confined to asmallnumber of countries, mean that it will not be financially viable to extract these deposits. Assuming high grade glauconitic sand with the right composition can be located, the high market price indicates good future prospects for these potash deposits.  相似文献   
4.
陈履安 《贵州地质》2011,28(3):237-240
针对当前有些拥有不溶性含钾岩石的地区,仍然积极推动含钾岩石的工业提钾生产钾肥的现状,本着科学决策、民主决策的精神,本文通过国内外含钾岩石研发的历史与现状,以及钾盐肥料产业的快速发展态势和市场分析,认为在今后一个相当长时间内,开发含钾岩石工业生产钾肥不是解决我国钾肥资源短缺的可行途径。把含钾岩石作为钾肥原料、工业生产可溶...  相似文献   
5.
兰坪-思茅盆地与呵叻高原钾盐矿床综合对比   总被引:2,自引:1,他引:1       下载免费PDF全文
云南兰坪—思茅盆地与泰国-老挝呵叻高原处于同一构造带,两者在钾盐成矿及成因各方面都有着很大的相似性。通过对兰坪—思茅盆地与呵叻高原成矿地质背景、成盐时代、成盐物源和环境、沉积和地球化学特征等多方面对比分析,系统阐述了二者的异同,重点强调了存在的差异性,提出了一些今后开展工作的意见和建议。  相似文献   
6.
柴达木盆地是我国重要的钾肥基地,年产氯化钾超过700×10~4t,副产尾盐超过1 000×10~4t,尾盐的主要组分是氯化钠,并夹带少量的氯化钾。通过精制试验研究,进一步回收氯化钾,氯化钠则作为纯碱原料,实现了尾盐的梯级综合利用,对促进盐湖循环经济发展具有重要意义。试验表明,采用二段洗涤工艺,结合喷淋和搅拌两种洗涤方式处理钾肥生产浮选尾盐,浮选尾盐经二段洗涤所得产品中氯化钠含量达到92.54%,符合纯碱所需原盐指标要求;母液中的氯化钾富集到一定程度后,回收可作为钾肥生产原料。  相似文献   
7.
选矿厂设计是矿山建设中极其重要的关键环节。做好选矿厂设计工作,对于节省项目建设投资,确保工厂如期达产达标,并取得良好的经济效益,具有决定性的作用。本文结合老挝开元500 kt/a氯化钾项目选矿厂生产过程中的技术改造与创新,对该类型选矿厂设计进行经验总结,并指明设计中仍需优化与创新的环节。选矿厂设计中工艺流程的选择应具有较强的生产兼容性,且工艺流程主要环节之间有灵活的可切换性,以适应井下开采过程中性质多变的原矿。工艺配置,设备选型和厂房设计既要兼顾原矿和产品性质,也要充分考虑当地的气候条件和自然环境。厂房和工艺设备的防腐,自动化技术的开发应用和工艺流程样品的自动采集与分析是未来仍需优化和创新的重要环节。本研究可为今后同类选矿厂的设计提供有益的参考。  相似文献   
8.
老挝中部沙湾拿吉盆地上白垩统农波组钾盐蒸发岩是研究区域成矿卤水演化的重要材料。盐类矿物中微量元素的含量及其变化特征共同揭示了成盐物质应该主要来自海水,但深部水的补给也具有重要作用。研究结果表明,所谓的含盐系"基底"硬石膏只是水-岩作用下下盐层底部溶滤后的残余物。光卤石中偏负的δD、δ18O值及Br的海相特征则指示了该矿物是浓缩海水混合大气水后蒸发的产物,陆相水对成矿卤水演化过程产生了一定影响。农波组下盐层蒸发岩可分为3个不同的演化阶段。(1)海相输入阶段:海水进入成盐盆地,石盐大量沉积,海侵作用早期具有明显的波动性而后期较稳定;该阶段末期发生了海相输入向陆相输入的转变,陆相输入在水文封闭和收缩的成盐盆地中逐渐占据主导地位,卤水组分因深部水输入而发生变化。(2)非海相输入及混合卤水蒸发阶段:混合卤水蒸发形成钾盐,光卤石沉积过程中发生了一次轻微的卤水淡化事件。(3)沉积后改造阶段:已沉积的光卤石岩在陆相水淋滤作用下转变为钾石盐岩,钾石盐是光卤石被交代后的次生矿物。系统的微量元素和氢氧同位素分析表明,非海相输入在成矿卤水演化及沉积后的改造过程中扮演了重要角色。  相似文献   
9.
Zechstein (Z1) rocksalt from the Fulda basin, from the immediate vicinity of the Hessen potash bed is folded into tight to isoclinal folds which are cut by an undeformed, 1 cm thick, coarse-grained halite vein. Microstructures were investigated in etched, gamma-irradiated thin sections from both the wall rock and the vein. The lack of synsedimentary dissolution structures and the widespread occurrence of plate-shaped and hopper grains in the wall-rock suggests that the sedimentary environment was perennial lake. Deformation microstructures are in good agreement with solution-precipitation creep process, and salt flow under very low differential stress. Strength contrast between anhydrite-rich and anhydrite-poor layers caused the small scale folding in the halite beds. The vein is completely sealed and composed mainly of euhedral to subhedral halite grains, which often overgrow the wall-rock grains. Those microstructures, together with the presence of occasional fluid inclusion bands, suggest that the crystals grew into a solution-filled open space. Based on considerations on the maximum value of in-situ differential stress, the dilatancy criteria, the amount of released fluids from the potash bed during metamorphism and the volume change, it is proposed that the crack was generated by hydrofracturing of the rocksalt due to the presence of the salt-metamorphic fluid at near-lithostatic pressure.  相似文献   
10.
The reduction and the smoothened amplitudes of the chloride concentrations since 2000 have resulted in a gradual positive development of the aquatic fauna in the River Werra. In the salinized section of the river increasing species numbers have been determined along the salinity gradient, which shows maximum chloride concentrations of about 2500 mg/l, maximum potash concentrations at approximately 200 mg/l, and magnesia concentrations peaked at 320 mg/l. As an immediate consequence of the reduction in salt concentration the immigration of various caddis fly species into the lower River Werra was observed. The Number of taxa per sample rose from 5 to more than 30 in the lower Werra region. Changes in species-richness could be seen more frequently in river sections where chloride concentrations fluctuated around 1500 mg/l.  相似文献   
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