济南某地区裂隙岩溶地下水硝酸盐污染现状及溯源浅析   总被引：1，自引：0，他引：1  

卢兆群  成世才  宋永芬  张强 《化工矿产地质》2016,(4):226-231

通过对历史资料的对比,揭示了济南某地裂隙岩溶地下水中硝酸根污染现状,并通过三线图法对硝酸根进行溯源分析,显示研究区地下水硝酸根含量受人类活动影响明显,并有进一步发展的趋势。相关性分析法分析结果显示地下水硝酸根含量与Cl相关,说明其与工业废水联系密切,而土壤剖面中硝酸根含量显示,土壤中硝酸根含量的顺序为:禽畜粪便污染类污水排放污染类垃圾堆放污染类。分析认为,研究区裂隙盐溶承压水硝酸根污染的来源主要为补给区及径流区强烈渗漏携带牲畜粪便及氮肥和农家肥的施用、生活污水、工业废水及浅层水混入。  相似文献   

安徽淮北朔里煤矿硬质高岭土矿石特征及自然类型划分     

韩冲  李全海 《安徽地质》2008,18(1):26-28

朔里煤矿共生硬质高岭土矿赋存在下石盒子组底部的铝土泥岩中;其主要矿物为高岭石,次要矿物软水铝石,另有少量赤铁矿、金红石、锐钛矿等铁钛矿物;化学成分以Al2O3、SiO2为主,Fe2O3＋TiO2含量超过2％则不能圈定为矿体。朔里煤矿共生硬质高岭土矿共划分四种自然类型：①灰白-浅灰色高岭土矿,②深灰-灰黑色高岭土矿,③花斑状高岭土矿,④灰色含黄铁矿或少量鲕状菱铁矿高岭土矿。  相似文献   

巴彦塔拉油田南屯组、铜钵庙组岩性识别方法研究     

闫伟林  张剑风  王德平 《上海国土资源》2008,(2):63-66

巴彦塔拉油田南屯组、铜钵庙组地层属白垩系,岩性复杂,具有放射性的凝灰质对自然伽马值影响较大,难以用自然伽马来识别含泥地层,针对储层这一特点,提出了利用RLLD—AC交会图识别凝灰质的新途径;依据该区9口井测井、岩心和薄片分析资料,利用一套分步识别该区岩性的交会图方法,对该区巴X2和巴1两井取心井段进行岩性识别,符合率达91．7％,对研究区储层评价及与该区有类似地质特征的油田岩性识别有一定的指导意义。  相似文献   

Benthic megafauna on steep slopes at the Northern Mid‐Atlantic Ridge          下载免费PDF全文

James B. Bell  Claudia H. S. Alt  Daniel O. B. Jones 《Marine Ecology》2016,37(6):1290-1302

The role of small‐scale (<10 km) habitat availability in structuring deep‐sea hard substratum assemblages is poorly understood. Epibenthic megafauna and substratum availability were studied on steep slopes at the Mid‐Atlantic Ridge from May to July 2010 northwest, northeast, southwest and southeast of the Charlie‐Gibbs Fracture Zone (CGFZ; 48–54°N) at between 2095 and 2601 m depth. Megafauna were six times denser north of the CGFZ compared with the south and differences in density were almost entirely driven by sessile fauna. There was no significant difference in habitat availability amongst sites. Rocky substratum made up 48% of the total area surveyed, with individual transects having between 0% and 82% rock. Assemblage structures were different amongst all superstations. The north was dominated by demospongids and hexactinellids, whereas the southern superstations were dominated by anthozoans and hexactinellids. Differences in megafaunal assemblages north and south of the CGFZ primarily reflected variations in demospongid and anthozoan species composition. With 213–1825 individuals·ha^?1, and 7–24 species per superstation, hexactinellids were the most species‐rich (36 species) and cosmopolitan taxa at the study site, supporting observations elsewhere along the ridge and in the CGFZ. The absence of significant differences in substrata availability suggested alternative drivers for density or percentage cover. The amount of hard substratum available only limited sessile megafauna density at one transect that was entirely covered with sediments. Species richness was highest for areas with intermediate values of substratum coverage (35–43% rock).  相似文献   

A new version of the USLE‐MM for predicting bare plot soil loss at the Sparacia (South Italy) experimental site          下载免费PDF全文

Vincenzo Bagarello  Vito Ferro  Vincenzo Pampalone 《水文研究》2015,29(19):4210-4219

Improving empirical prediction of plot soil erosion at the event temporal scale has both scientific and practical importance. In this investigation, 492 runoff and soil loss data from plots of different lengths, λ (11 ≤ λ ≤ 44 m), and steepness, s (14.9 ≤ s ≤ 26.0%), established at the Sparacia experimental station, in Sicily, South Italy, were used to derive a new version of Universal Soil Loss Equation (USLE)‐MM model, by only assuming a value of one for the topographic length, L, and steepness, S, factors for λ = 22 m and s = 9%, respectively. An erosivity index equal to (Q_REI₃₀)^b1, Q_R and EI₃₀ being the runoff coefficient and the event rainfall erosivity index, respectively, with b₁ > 1 was found to be an appropriate choice for the Sparacia area. The specifically developed functions for L and S did not differ appreciably from other, more widely accepted relationships (maximum differences by a factor of 1.22 for L and 1.09 for S). The new version of the USLE‐MM performed particularly well for highly erosive events, because predicted soil loss differed by not more than a factor of 1.19 from the measured soil loss for measured values of more than 100 Mg ha^?1. The choice of the relationships to predict topographic effects on plot soil loss should not represent a point of particular concern in the application of the USLE‐MM in other environments. However, tests of the empirical approach should be carried out in other experimental areas in an attempt to develop analytical tools, usable at the event temporal scale, reasonably simple and of wide validity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

坚硬顶板运动特征的数值模拟及非线性动力学分析   总被引：8，自引：1，他引：7  

刘传孝 《岩土力学》2005,26(5):759-762

分别从三维离散单元法及非线性动力学方法两个角度研究了坚硬顶板的运动规律,得到了较一致的结论。坚硬顶板的初次垮落具有冲击性,应力水平较高,该阶段的LE1为负值,系统处于有序的定常态;所研究条件下实施防冲措施的最佳时机在第2阶段开采活动结束之前,可促使坚硬顶板从冲击性整体运动向周期性分段运动转化;∑(+LEi)表明第4阶段的混沌程度最高,对应应力水平适中的周期性运动阶段。研究表明,除了初次冲击性垮落阶段,坚硬顶板运动系统在其它阶段均处于孕育着变化的混沌态。  相似文献   

坚硬顶板采场采空区岩层离层遥测研究     

赵同彬  谭云亮  马洪岭 《岩土力学》2006,27(Z1):381-384

利用梁弯曲理论,根据岩层间变形不协调性关系,建立了坚硬顶板离层的判别条件,并指出了相应参数对顶板变形的相对影响程度。采用遥测技术监测坚硬顶板采场采空区岩层离层,结果表明,遥测系统可以有效采集到顶板岩层离层发育信息,通过监测曲线的分析,能够确定采空区顶板产生离层的位置,进而可预测出顶板垮落厚度。利用遥测系统采集到采空区顶板失稳前的离层信息,及时采取相应的措施,可保证坚硬顶板煤层安全开采。  相似文献   

淄博盆地A层硬质黏土—铝土矿矿床地质特征及分布规律          下载免费PDF全文

刘东义  韩鎏  郑骥飞  胡小辉 《山东国土资源》2020,36(10)

山东淄博盆地A层硬质黏土—铝土矿主要赋存于二叠纪石盒子群万山组底部的A层含矿岩系中,矿体呈似层状和透镜状产出,A层硬质黏土在该区分布较广,而共生铝土矿矿体主要分布在东宝山—东冲山一带;两矿体的形态、结构、构造比较简单。两矿体垂向分布呈渐变关系,受沉积环境影响呈现不同的颜色和结构,肉眼可大致区分矿体与围岩,具体界线要靠化学分析结果予以区分;矿体厚度均匀,总体与Al_2O_3,SiO_2含量呈正相关,与Fe_2O_3呈反相关;矿石中Al_2O_3,Fe_2O_3,SiO_2的总含量一般在83.5%～85.5%,品位比较均匀,同时三者含量在不同矿石中有着相互消长的关系。  相似文献   

Variation in curve numbers derived from plot runoff data for New South Wales (Australia)     

Hongxia Cao  R. Willem Vervoort  Seth M. Dabney 《水文研究》2011,25(24):3774-3789

The curve number method is a simple one parameter (the curve number) rainfall runoff model. While its theoretical underpinning has been questioned it remains a powerful hydrological tool in the absence of detailed data and is therefore used extensively in hydrological models. This study aims to characterize the variation in maximum retention values (S), which underlie curve numbers, for a range of agricultural treatments across a large spatial area in New South Wales (NSW), Australia. The data used for the analysis spans several decades of rainfall runoff observations. A range of different derivation methods result in variation in mean and variance of S. In particular, methods that emphasize the larger storms result in greater S and thus lower runoff. For larger spatial scales, emphasis on larger storms gives more reliable estimates of S. Systematic variation in S arises from variations in treatment, pre‐runoff soil moisture, rainfall depth, and variations in cover. On the basis of the analysis, a table of curve number values for different land uses found in NSW is presented. The resulting distributions of S and curve numbers provide guidance for rainfall runoff modelling studies in the agricultural important areas of NSW. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

四川盆地东北部二叠系层序发育的动力学分析   总被引：1，自引：1，他引：0  

李凤杰  刘琪  刘殿鹤  刘犟 《地层学杂志》2010,34(1)

运用可容空间分析法,在野外剖面岩性、岩相厚度和旋回变化分析的基础上,对川东北地区宣汉县渡口镇羊鼓洞二叠系剖面的旋回层序进行研究,识别出3种类型5种亚类型的高频旋回层序类型,并将剖面中栖霞组、茅口组以及吴家坪组下部划分为118个高频旋回层序。根据测井曲线的旋回变化,将普光4井的长兴组划分出49个高频旋回层序,据此运用Fischer图解绘制了二叠系可容空间变化曲线。将可容空间变化曲线与相对海平面升降曲线之间进行对比发现,二者之间存在着良好的对应关系。采测井曲线的频谱分析,对研究区长兴组进行了米兰科维奇沉积周期进行研究,结果表明:长兴组中广泛地保存着124,44.89,35.11,21.16和17.72ka的米兰科维奇沉积周期;地层中的沉积旋回主要受古气候变化的控制,偏心率、地轴倾角和岁差周期引起的地层旋回厚度变化范围分别为:12.47—13.74m,3.56—5.21m,1.78—2.41m,其中受偏心率周期的影响最大。在构造活动相对较弱的川东北二叠系中,层序发育的动力学因素主要为相对海平面的变化和气候变化两个方面。相对海平面的变化主要是三级层序的控制因素,而气候变化则是高频层序旋回的主要动力。  相似文献