An analytical method of analysing the oscillatory pressure head measured at any depth in a well casing     

Chia‐Shyun Chen 《水文研究》2008,22(8):1119-1124

When a slug test is conducted in a highly permeable aquifer, a shallow pressure transducer in the well casing produces an oscillatory pressure head that is representative of the water level fluctuation, whereas a deep pressure transducer in the well casing yields an oscillatory pressure head that is different from the water level change. Although the solutions for shallow and deep pressure head are different, it is found that the ratios of the subsequent extremity displacements are in an identical relationship (an extremity can be a maximum or a minimum in the oscillatory pressure head). Based on this relationship, an analytical data analysis method for the determination of the hydraulic conductivity is developed for both shallow and deep pressure transducer data. This analytical method is applied to the pressure head measured at different depths in the well casing of a well partially penetrating an unconfined coarse sand aquifer. Satisfactory results are obtained, validating the applicability of this analytical method for pressure transducer data at any depth in a well casing. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

适合海洋钻井无土相强抑制性钻井液体系的研究     

梁文利  赵林 《海洋地质译丛》2008,(1):88-92

在渤海湾盆地,由于沉积地层存在大段活性软泥页岩,普通聚合物钻井液体系的包被抑制能力不够,封堵能力不强,剪切稀释能力差,在钻遇该泥页岩井段时,经常出现井下复杂情况,并且油层受到一定程度的伤害。为此,研制了无土相强抑制性钻井液体系。从体系中处理剂的防塌抑制机理出发,确定了强抑制性钻井液体系构建的最优组合。研究结果表明该钻井液体系具有强的抑制性,岩屑滚动回收率达到95.6%,接近于油基泥浆;并且具有良好的润滑性、抗温性、抗钻屑污染、抗CaCl2污染、抗MgCl2污染以及良好的储层保护性能,渗透率恢复值能达到85%以上,能够满足大段软泥页岩等复杂地层的钻井要求,具有广阔的应用前景。  相似文献   

板块碰撞产物——强应变构造带对东准噶尔金矿的控制   总被引：9，自引：1，他引：8  

高怀忠  张旺生 《地质与勘探》2000,36(3):15-17,21

东准噶尔强应变构造带是板块碰撞作用的产物 ,控制了金成矿带的分布 ,而金的矿化富集地段分布于强应变构造带与走向北北西的断裂交汇部位。金矿体及矿脉则形成于强应变构造带的次级断裂和裂隙中。  相似文献   

浙江安吉坞山关杂岩体岩相学和岩石地球化学特征及岩石成因   总被引：1，自引：0，他引：1  

唐燕文  谢玉玲  李应栩  邱立明  刘保顺  李媛  张欣欣  姜妍岑  韩宇达 《矿床地质》2012,31(4):903-916

位于钦—杭成矿带东段北缘的浙江安吉多金属矿区发育侵位序列复杂的坞山关杂岩体及与其有关的蚀变和矿化.为了探讨区内岩浆岩与成矿的关系,在野外调查的基础上,文章对该杂岩体的岩相学、岩石地球化学开展了研究,并籍此对其成因类型、源区特征进行了探讨.坞山关杂岩体由黑云母二长花岗岩、花岗闪长岩和正长花岗岩组成,前者具富碱、高钾特征,属准铝质-钾玄岩系列,花岗闪长岩具高钾特征,属准铝质-高钾钙碱性系列,正长花岗岩具高硅、低钙、贫镁、高FeO/MgO值、富碱特征,属准铝-弱过铝质钾玄岩系列.该杂岩体的∑REE为(123.5～216.47)×10-6,稀土元素配分型式呈明显的右倾轻稀土元素富集型,Eu呈不同程度的负异常.微量元素蛛网图中,各岩石单元大离子亲石元素(尤其是Rb、Th、K)明显富集,Ba、Sr负异常明显,相对亏损高场强元素Nb、Ti、P.该杂岩体成矿元素ω(Mo)、ω(W)明显高于克拉克值,暗示其具有提供成矿物质的潜力.黑云母二长花岗岩为分异Ⅰ型花岗岩,花岗闪长岩属Ⅰ型花岗岩,正长花岗岩具有A型花岗岩的多数特征,但从杂岩体各岩石单元的成岩年龄相差不大、具地球化学亲缘性以及A型花岗岩不具高分异特征来考虑,将其归为高分异Ⅰ型花岗岩更理.La/Sm-La图解显示出,该杂岩体为平衡部分熔融作用所形成,其轻稀土元素富集、Ta-Nb、Ti、Eu、Sr、Ba负异常可能是源区为含角闪石族、金红石、斜长石作为难熔相遗留在残留物中所致.  相似文献   

A constitutive model for the dynamic and high‐pressure behaviour of a propellant‐like material: Part I: Experimental background and general structure of the model     

Herv Trumel  Andr Dragon  Alain Fanget  Philippe Lambert 《国际地质力学数值与分析法杂志》2001,25(6):551-579

This paper is the first part of a work that aims at developing a mechanical model for the behaviour of propellant‐like materials under high confining pressure and strain rate. The behaviour of a typical material is investigated experimentally. Several microstructural deformation processes are identified and correlated with loading conditions. The resulting behaviour is complex, non‐linear, and characterized by multiple couplings. The general structure of a relevant model is sought using a thermodynamic framework. A viscoelastic‐viscoplastic‐compaction model structure is derived under suitable simplifying assumptions, in the framework of finite, though moderate, strains. Model development, identification and numerical applications are given in the companion paper. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

LG植物胶泥浆在煤田复杂地层钻探中的应用研究          下载免费PDF全文

张晓静乌效鸣  蔡记华张家军韩书记  周文波 《探矿工程》2006,33(12):42-44,49

在河南省驻马店汝南县林楼一正阳县张楼一带的煤田勘探中，第三、第四系地层厚达700m，经常遇到水敏性粘土、砂质粘土、砂质泥岩、粉砂岩和卵砾石等地层，易造成缩径、超径、坍塌和掉块等孔内复杂情况。结合该地区的地层特征，采用新型LG植物胶泥浆来解决钻探的“瓶颈”难题。应用实践表明，LG泥浆起到了显著的抑制缩径、超径和防塌作用，大大减少了孔内事故的发生，提高了钻进效率。  相似文献   

2009-2015年国际青藏高原研究文献计量分析——基于SCIE和ESI数据     

王婷 《地理科学进展》2017,36(4):500-512

青藏高原及其周边地区以独特的自然地理环境和复杂的地质构造,及其对全球环境和气候变化不可忽视的影响,长期以来一直受到国际科学家的关注。本文以SCIE和ESI数据库为数据源,检索2009-2015年间上述数据库报道的青藏高原及其周边地区研究文献及其引用情况,通过文献计量方法,采用多种分析工具,从多个角度对青藏高原及其周边地区研究现状与进展情况进行分析,在此基础上总结近年来国际青藏高原领域的研究态势,主要结论为：整体上近年来国际青藏高原领域研究规模和学术影响力呈现良好发展态势;研究实力上,中国、印度、美国仍稳居国家论文产出前三位,但青藏高原周边国家如巴基斯坦、尼泊尔发展较快,在机构层面上中国机构的整体优势逐渐扩大。中国的青藏高原研究呈现出量、质齐升的发展态势;青藏高原的发文期刊仍以地学、环境类期刊为主,高被引论文主要发表在高质量的综合类期刊上。青藏高原的研究学科持续完备,研究内容地域特色明显,研究主题包括青藏高原的隆升机制、高原各个圈层对全球气候变化的影响、高寒生态系统的生物多样性及对全球变暖的响应等。今后,中国青藏高原研究应着力聚焦前沿科学问题,促进多学科交叉融合,提升协同化集成化自主科研创新能力,产出具有国际影响力的重大科学成果,为“一带一路”战略实施和区域生态环境管理提供科技支撑。  相似文献   

Genetic heterogeneity of Atlantic bluefin tuna caught in the eastern North Atlantic Ocean south of Iceland   总被引：2，自引：0，他引：2  

Carlsson  Jens; McDowell  Jan R.; Carlsson  Jeanette E.L.; Olafsdottir  Droplaug; Graves  John E. 《ICES Journal of Marine Science》2006,63(6):1111-1117

  相似文献   

老挝-越南长山成矿带北西段高分异I型花岗岩LA-ICP-MS锆石U-Pb年龄及其地质意义          下载免费PDF全文

高建华  吴振波  范文玉  王宏 《沉积与特提斯地质》2016,36(4):85-94

马江结合带俯冲时代一直是地质研究的热点问题,老挝-越南长山成矿带花岗岩的构造属性是对马江洋闭合时间的重要制约。本文报道了老挝-越南长山成矿带北西段的中细粒花岗岩,其LA-ICP-MS锆石U-Pb年龄为261.34 ±0.69 Ma (MSWD=1.4),为晚二叠世。岩石具有高SiO₂(77.01%~78.07%)、高K₂O (4.32%~4.57%)、低钙镁(CaO=0.32%~0.34%;MgO=0.04%~0.06%)和低P₂O₅含量特征,富集Rb、U、Th,明显亏损Ba、Sr、P、Ti和Eu等,属高分异I型花岗岩。该岩体可能是马江洋岩石圈南向俯冲的背景下,由俯冲海洋岩石圈诱导的幔源岩浆侵入古老地壳,形成初生地壳,在后期持续的热事件的影响下,提供足够的热引起初生地壳和古老地壳的混合地壳部分熔融,形成母岩浆,再经历高度分离结晶作用形成。  相似文献   

Use of Hydrofluoric Acid Desilicification in the Determination of Highly Siderophile Element Abundances and Re‐Pt‐Os Isotope Systematics in Mafic‐Ultramafic Rocks          下载免费PDF全文

James M.D. Day  Christopher L. Waters  Bruce F. Schaefer  Richard J. Walker  Simon Turner 《Geostandards and Geoanalytical Research》2016,40(1):49-65

Properly combining highly siderophile element (HSE: Re, Pd, Pt, Ru, Ir, Os) abundance data, obtained by isotope dilution, with corresponding ¹⁸⁷Os/¹⁸⁸Os and ¹⁸⁶Os/¹⁸⁸Os measurements of rocks requires efficient digestion of finely‐ground powders and complete spike‐sample equilibration. Yet, because of the nature of commonly used methods for separating Os from a rock matrix, hydrofluoric acid (HF) is typically not used in such digestions. Consequently, some silicates are not completely dissolved, and HSE residing within these silicates may not be fully accessed. Consistent with this, some recent studies of basaltic reference materials (RMs) have concluded that an HF‐desilicification procedure is required to fully access the HSE (Ishikawa et al. (2014) Chemical Geology, 384, 27–46; Li et al. (2015) Geostandards and Geoanalytical Research, 39, 17–30). Highly siderophile element abundance and Os isotope studies of intraplate basalts typically target samples with a range of MgO contents (< 8 to > 18% m/m, or as mass fractions, < 8 to > 18 g per 100 g), in contrast to the lower MgO mass fractions (< 10 g per 100 g) of basalt and diabase RMs (i.e., BIR‐1, BHVO‐2, TDB‐1). To investigate the effect of HF‐desilicification on intraplate basalts, experiments were performed on finely ground Azores basalts (8.1–17 g per 100 g MgO) using a ‘standard acid digestion’ (2:1 mixture of concentrated HNO₃ and HCl), and a standard acid digestion, followed by HF‐desilicification. No systematic trends in HSE abundances were observed between data obtained by standard acid digestion and HF‐desilicification. Desilicification procedures using HF do not improve liberation of the HSE from Azores basalts, or some RMs (e.g., WPR‐1). We conclude that HF‐desilicification procedures are useful for obtaining total HSE contents of some young lavas, but this type of procedure is not recommended for studies where Re‐Pt‐Os chronological information is desired. The collateral effect of a standard acid digestion to liberate Os, followed by HF‐desilicification to obtain Re and Pt abundances in samples, is that the measured Re/Os and Pt/Os may not correspond with measured ¹⁸⁷Os/¹⁸⁸Os or ¹⁸⁶Os/¹⁸⁸Os.  相似文献