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61.
Potassium-rich brine in the Sichuan Basin has been much studied in recent years, but few studies have focused on the distribution and migration of salt basin and the differences of potassium formation mechanisms. This work examined the salt-gathering and potassium formation of potassium-rich brine during the Triassic in the Sichuan Basin using lithofacies palaeogeographic depiction and geochemical analyses. (1) The favorable sedimentary facies controlling the formation of potassium-rich brine during the Triassic in the Sichuan Basin are evaporation platform and restricted platform, whereas the salt basin is one of the main factors controlling the poly-salt center. (2) The distribution and migration of this salt basin were affected by certain factors. The salt basin of the Jialingjiang Formation was mainly distributed in the east and central Sichuan Basin, whereas that of the Leikoupo Formation was mainly distributed in the central and west Sichuan Basin. The sedimentary centers have gradually moved westward and become smaller. (3) Three main formation mechanisms were identified for the potassium-rich brine during the Triassic in the Sichuan Basin, i.e., evaporation and concentration of seawater, surface fresh water leaching, and deep water-rock reaction. Fresh water leaching was characterized by low anomaly δ18O and δ13C values. Water-rock reaction was mainly related to temperature, and high temperature environment (caused by burial depth, overthrust and deep hydrothermal fluids) was beneficial to water-rock reaction. The characteristics of water-rock reaction do not correspond to the increase ratio of K?103/Cl and Br?103/Cl in brine, and the Rb+ content of the brine was high. (4) The formation mechanisms of potassium-rich brine differed between different areas of the Sichuan Basin. In east Sichuan, the evaporation and concentration of seawater, together with meteoric fresh water leaching, was the main formation factor, whereas the evaporation and concentration of seawater and water–rock reaction predominated in west Sichuan. This study of the sedimentary environment and formation mechanisms is of significance to the exploration and exploitation of potassium-rich brine in the Sichuan Basin.  相似文献   
62.
Abstract Fluids, some of which are CO2-rich (up to 40 mol.% CO2) and some of which are highly saline (up to 18 wt% NaCl equivalent), are trapped as fluid inclusions in quartz-calcite (∼ metallic minerals) veins which cross-cut the pumpellyite-actinolite to amphibolite facies rocks of the Alpine Schist. Fluids were commonly trapped as immiscible liquid-vapour mixes in quartz and calcite showing open-space growth textures. Fluid entrapment occurred at fluid pressures near 500 bars (possibly as low as 150 bars) at temperatures ranging from 260 to 330° C. Saline fluids may have formed by partitioning of dissolved salts into an aqueous phase on segregation of immiscible fluids from a low-density CO2-rich fluid. Calcite deposited by these fluids has δ13C ranging from – 8.4 to – 11.5 and δ18O from + 4 to + 13. Isotopic data, fluid compositions and mode of occurrence suggest that the fluids are derived from high-grade metamorphic rocks. Fluid interaction with wall-rock has caused biotite crystallization and/or recrystallization in some rocks and retrogression of biotite to chlorite in other rocks.
Fluid penetration through the rock is almost pervasive in many areas where permeability, probably related to Alpine Fault activity, has focussed fluids on a regional scale into fractured rocks. The fluid flow process is made possible by high uplift-rates (in excess of 10 mm/year) bringing hot rocks near to the surface.  相似文献   
63.
柴达木盆地西部卤水水化学特征与找钾研究   总被引:11,自引:0,他引:11  
柴达木盆地自中生代末-新生代初以来,四周山体不断抬升,形成"高山深盆"的沉积环境,为盆地带来了大量盐类物质,再加上晚第三纪干旱封闭的气候环境,使其西部沉积了广阔而厚层的盐岩.在对柴达木盆地西部第三系、第四系地层出露盐矿点实地考察的过程中,采集、分析了22件水样品的水化学组成,通过K+含量及一些水化学系数变化特征的研究,查明了卤水的水化学类型主要为氯化物型和硫酸镁亚型,其成因基本属溶滤岩盐卤水、深部循环水以及二者的混合水体,Br-、B3+、Sr2+、Li+等微量离子含量较高,区域差异性较大,出现显著水化学系数异常;相比之下,柴达木盆地西部南翼山坳陷Br-、B3、Sr2+、Li+含量值明显高于昆特依、察汗斯拉图、油砂山、开特米里克、油泉子、油墩子等坳陷区.Br×103/Cl、K×103/Cl等具找钾意义的水化学系数比其他地区高1~2倍,Br-、K+出现相对的富积,推测该坳陷成盐原始卤水曾浓缩达到较高析盐阶段或可能有大量深部富钾水体的补给,可作为寻找钾盐矿(富钾卤水)重点区域之一.  相似文献   
64.
宣达盐盆富钾富矿卤水产于四川盆地东北部黄金口背斜群南段付家山构造近高点,以深层卤水形式赋存于3260m左右的下三叠统嘉陵江组五段和中统雷口坡组一段(T1j5-T2L1)盐系的碳酸盐岩储层中。卤水与海水蒸发系列相比,K+含量异常高,达25 96g L,超过海水钾盐沉积阶段,也超过综合利用和单独开采品位,为国内外罕见的液态钾矿资源。且富含I-,B3+,Li+,Rb+,Sr2+等多种有用组分,品质优异,构成优质化工原料水,为一种综合性富钾富矿液态矿藏,经济价值极高。卤水为沉积变质水和固态钾盐溶滤水的复合成因。开发利用将可为农业提供优质钾肥,缓解我国钾盐资源不足,并可提供多种短缺的化工产品,对固态钾盐找矿具有重要现实意义。  相似文献   
65.
The Bou-Dahar PbZn Mississippi Valley deposits located in the eastern part of the High Atlas Range (Morocco) are hosted by a Liassic reefal complex. Fluid inclusion and ‘crush-leach’ data show that two distinct fluids were involved in the mineralisation deposition: a warmer, more saline fluid (180?°C, >25wt% NaCl equivalent) and a cooler, less saline fluid (70?°C, 16 wt% equivalent NaCl). Mixing of these two fluids resulted in the precipitation of the ore. The solute composition of the ore-forming brine suggests that the MVT mineralising fluids were probably a mixture of halite-dissolution fluids and evaporated seawater. To cite this article: S. Adil et al., C. R. Geoscience 336 (2004).  相似文献   
66.
卤水制备氢氧化锂研究进展   总被引:4,自引:1,他引:4       下载免费PDF全文
简单介绍了氢氧化锂的性质,对氢氧化锂的需求和应用作了简要描述。重点介绍了卤水制备氢氧化锂的方法和工艺,并展望了卤水生产氢氧化锂的前景。  相似文献   
67.
沉积盆地卤水来源的非传统同位素示踪研究进展   总被引:1,自引:0,他引:1  
世界上大多数的沉积盆地内,在结晶基底或者沉积地层内都有矿化度较高的卤水,由于这些卤水通常携带或富含有钾、硼、锂、溴、碘、铷、铯、稀有气体及重金属元素,因此,它们是地学界的研究热点之一。随着测试技术的不断进步,非传统同位素的应用也日益广泛,但在沉积盆地卤水来源和演化方面的研究还十分薄弱,对卤水的来源和演化也还存在争议。文章回顾了硼、锂、碘和惰性气体氦、氩同位素在卤水来源研究方面的进展,并指出由于单一同位素在解释上的片面性,多种同位素相结合的示踪方法研究沉积盆地卤水的来源是国际趋势。  相似文献   
68.
上世纪在江陵凹陷的石油钻孔中发现了深层富钾卤水矿层,但是卤水矿层的空间展布一直不清。借用油气勘探领域中地球物理储层预测方法和理论,利用钻孔对矿层的垂向高分辨率的识别,标定到三维地震剖面上,利用多种地震属性横向高分辨率识别卤水矿层,预测矿层的空间分布,为靶区钻孔的部署提供依据。文章利用已经发现富钾卤水矿层的路9井的资料,开展模型正演,发现地震中振幅、频率、波形等属性可以较好地识别卤水矿层;将路9井的卤水矿层标定到地震剖面上,通过提取地震属性,识别出的富钾卤水矿层平面面积达5.53 km2;在该富钾卤水区中部署的岗钾1井,钻探获得高产富钾卤水矿层,验证了地球物理探测深层富钾卤水方法的正确性。  相似文献   
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