排序方式： 共有5条查询结果，搜索用时 78 毫秒
1
1.
文章依据嫩江县七星泡农场一带的地质、地质构造、水文地质及水文地球化学环境,以及矿泉水水质检验结果,论述了七星泡酸性矿泉水的成因及分布规律。指出酸性矿泉水赋存于白垩系上统嫩江组砂岩、砂砾岩孔隙、裂隙承压水含水层中,由于含水层中含黄铁矿结核,为酸性矿泉水的形成提供了物质来源。受燕山中晚期断裂构造的影响,白垩系上统嫩江组在七星泡农场一带由封闭的还原环境,转变为开放半开放的氧化环境,黄铁矿氧化、发生硫酸化作用,致使地下水呈酸性反应,形成了酸性矿泉水;断裂构造控制了酸性矿泉水的循环条件与分布规律。 相似文献
2.
Thorjorn Larssen 《中国地球化学学报》2006,25(B08):49-49
Acid rain is one of China＇s major environmental problems and emissions of sulphur and nitrogen are still increasing. The acid rain situation in China is somewhat different from what is seen in Europe and North America. Sulfur deposition is very high, but there is also very high deposition of calcium and other base cations. The sources of atmospheric Ca are not well understood, although it is important for understanding long term impacts of acid deposition. The fate of S, N and Ca^2＋ in the catchment is crucial for the future development of the acidification situation of soils and waters in China. Very few studies presenting catchment input-output ion budgets in Chinese natural environments exist and there are several unknown factors regarding processes. Here, we present annual input-output budgets for three years （2001-2003） for major ions for four forested catchments in China receiving different loads of acid deposition. For the two sites receiving the highest SO4^2- inputs, the input-output budget for the upper 50 cm of soil is approximately balanced. For the most remote site the soil is a net sink for SO4^2-, suggesting that the pool of adsorbed SO4^2- in the soil is building up. This is in agreement with the fact that the site so far has received only moderate SO4^2- inputs. For the southemmost, the subtropical site there is a loss of SO4^2- in the soil, which at least partly may be related to high uptake from the dense and highly productive forest at the site. The Ca^2＋ budgets for the upper 50 cm of soil show large variations both within and between sites. For most locations there is production of Ca^2＋ in the soil that can be explained by weathering, and variation between years related to hydrology that can be explained by ion exchange. However, at some plots at the site receiving very high inputs of both SO4^2- and Ca^2＋, there is an unknown sink of Ca^2＋ in the soil at some plots. 相似文献
3.
以一个堆放近20年的碳酸盐型尾矿的垂向剖面作为研究对象,采用综合地质-地球化学分析方法,包括尾矿组构及组分分析、X衍射分析以及Sobek-ABA估算和NAG测试等,探讨这类尾矿酸化的地质-地球化学特征及酸化作用机理,获得如下认识:①该尾矿剖面由下至上,随着氧化程度的增强,其酸化作用也逐步增强,呈现出明显的层带结构,即下部C层(还原带及原生带)为未蚀变松散尾砂,中部B层(次氧化带及碱缓冲带)为蚀变松散尾砂层,上部A层(氧化带及酸化带)呈厚约100～150cm的板结硬化层;在A层与B层之间形成一个酸化-碱缓冲界面;而氧化-还原界面则较低,位于B层底部接近C层顶部位置。②碱缓冲作用发生在B层内,方解石为碱质的主要来源。③该尾矿的酸中和有效率约为80%,这可能归因于尾矿酸化所产生的次生纤铁矿、石膏等包裹残余方解石,阻断了中和反应的进行。因此,即便是富含碱性碳酸盐的金属硫化物矿尾矿仍然存在酸化污染的可能性。 相似文献
4.
林文通 《矿物岩石地球化学通报》1993,(4)
近年来,对与中一新生代陆相火山活动有关的浅成热液金银矿床的成矿模式,如环太平洋全球性火山带金银成矿带内的金银矿床的成矿模式深受重视,对浅成热液金银矿床的沸腾-酸化成矿模式尤为赞赏。该模式是Reed和Spycher(1985,1989)等通过对现代活动的地热系统的金银矿化特征的详细观察与研究,并结合模拟实验而提出来的。 相似文献
5.
龙马溪组页岩作为贵州页岩气的主要储气层位,勘探及钻井均证实其具有良好的页岩气成藏条件和资源开发潜力。为揭示贵州龙马溪组页岩微观孔隙结构及其物性对酸化作用的响应规律,基于X射线衍射分析（XRD）、压汞、低温氮吸附及核磁共振（NMR）等实验手段,定量表征页岩酸化作用前后的孔隙体积、孔隙率、比表面积、孔径分布等页岩微观结构物性参数的差异性,分析酸化作用前后页岩孔裂隙的结构特征。研究表明:酸化作用增大了页岩的孔隙体积、孔隙率、比表面积和孔径,酸化作用后页岩进-退汞曲线及低温氮吸/脱附曲线的滞后环明显增大,酸化作用增大了墨水瓶孔的孔隙体积;受到酸化作用影响,页岩优势孔隙由介孔和110 nm左右大中孔向介孔与2 800 nm左右宏孔发展,介孔数量减少,宏孔数量增加,页岩孔隙的连通性明显变好;酸化对页岩孔裂隙中矿物质及黏土成分具有明显的化学溶解和刻蚀作用,对页岩孔裂隙体积的改造效果显著,增加了页岩储层的渗透性,进而提高了页岩气的运移与渗流能力;酸化作用下伴随的水化作用对页岩孔裂隙沿层理面起裂、扩展延伸起促进作用,但是页岩酸化作用下的水化作用机制尚需进一步研究。 相似文献
1