Environmental problems and geological implications derived from evaporite dissolution in the Barbastro salt anticline (NE Spain)

The halite-bearing Barbastro Formation crops out in the core of the Barbastro Anticline (Ebro Tertiary Basin). This anticline is traversed perpendicularly by some of the most important Pyrenean drainages such as the Cinca and Noguera-Ribagorzana Rivers. The terrace sequences of these fluvial systems have been used as markers to identify and assess dissolution-induced subsidence and salt tectonics. In the limbs of the anticline, terrace deposits underlain by detrital bedrock do not show any evidence of deformation and have a consistent thickness of less than 10 m. The deposits of certain terrace levels of the Noguera-Ribagorzana River and its tributary, the Lo Reguer Creek, are locally thickened filling basins generated by dissolution-induced synsedimentary subsidence up to several kilometers long and more than 100 m deep. Conversely, terraces of the Cinca River do not show anomalously high thicknesses, but local uplifts related to differential upward flow of the halite-bearing bedrock. Locally, a minimum uplift rate of 0.3 mm/year has been estimated from a 64-ka terrace tilted away from the valley. The subsidence hazards occur chiefly in areas where the ground receives artificial water recharge. Serviceability of some canals has been notoriously affected by evaporite karstification. The problem has been mitigated to acceptable levels by grouting. Numerous buildings of Ivars de Noguera are severely damaged by dissolution subsidence, and possibly, by hydrocompaction of gypsiferous silts. The pipe network has been replaced to ameliorate the subsidence risk. In the Cinca River valley, cavities with a total volume of about 180,500 m³ have been created by solution mining at depths greater than 500 m. No investigation methods are applied in the brine field to monitor the distribution and evolution of artificial voids. Substantial increase in salinity of the Cinca River is another evidence of subjacent evaporite dissolution.     

CitoMap地理信息数据采集系统的若干特点

系统地阐述了CitoMap的层次结构和特点;介绍了空间数据采集的工程管理和属性管理问题;论述了地图制图与地理信息数据采集相接合时的数据质量内容和控制方法;给出了CitoMap中专题制图和专业工程应用的解决方案。     

《盐湖研究》合订本征订启事

<正>《盐湖研究》是原国家科委批准的学术类自然科学期刊,由中国科学院青海盐湖研究所主办,科学出版社出版,1993年创刊并在国内外公开发行。《盐湖研究》自公开发行以来,深受广大读者的厚爱,为了便于我刊读者和文献情报服务单位系统收藏,编辑部藏有94-95年、96-97年、98-     

Homogeneous freezing of single sulfuric and nitric acid solution drops levitated in an acoustic trap

The freezing temperatures of single supercooled drops of binary and ternary sulfuric and nitric acid solutions were measured while varying the acid concentration. An acoustic levitator was used which allows to freely suspend single solution drops in air without electrical charges thereby avoiding any electrical influences which may affect the freezing process. The drops of typically 500 µm in radius were monitored by a video camera during cooling cycles down to − 85 °C to simulate the upper tropospheric and stratospheric temperature range. The present data confirm that liquid solution droplets can be supercooled far below the equilibrium melting point by approximately 35 °C. They follow the general trend of the expected freezing temperatures for homogeneous ice nucleation.     

单三角锁近似平差计算的虚拟附合导线法

本文指出了单三角锁近似平差计算传统算法的局限性;提出利用虚拟附合导线的形式,解决单三角锁计算问题的新算法;给出了新算法的详细计算过程。     

金坛石灰岩资源合理利用与供需保障分析

金坛非金属矿产资源比较丰富,石灰岩是主要的优势矿产。石灰岩原探明的储量有2亿多吨,但因部分储量位于茅山风景名胜区禁采区内不能利用,加之20多年来的开采消耗了较多储量,资源形势日趋严峻。有限的资源,持续上升的需求,供需矛盾严峻的形势摆在面前,为促进经济社会的可持续发展,必须加强对石灰岩资源的保护,科学配置、合理利用资源,以提高石灰岩矿资源保障能力。     

河流稀土元素地球化学研究进展

河流系统中,稀土元素(REE)受区域地质背景、风化作用、溶液化学以及水与颗粒物相互作用等因素的影响发生分异。河流悬浮物显示轻稀土(LREE)适度富集;河水显示重稀土(HREE)富集,或在HREE富集的基础上又有适度的中稀土(MREE)富集;与其它微量元素相比,REE在河水与颗粒物之间有较小的分配系数(K≈10-6);河流沉积物多显示平坦的REE配分模式。     

硼酸盐水溶液结构及研究方法

硼酸盐水溶液中多聚硼酸盐阴离子的分布及其平衡十分复杂。综述了水溶液中硼酸盐的主要存在形式、化学平衡及其研究方法。重点介绍和评价了离子交换、电导/电势滴定、11B核磁共振(11B NMR)、红外(IR)、拉曼光谱(Raman)、质谱(MS)等方法及其研究结论。对硼酸盐溶液结构研究的新方法如计算机模拟和衍射法,尤其是X射线衍射法(XRD)进行了介绍和展望。     

秦巴山区根类中药材气候适宜性区划

2008年秋冬季节长治市出现了严重的干旱。本文通过对2008年11月-2009年1月份北半球500hPa位势高度场和距平场的分析,发现西太平洋副高较常年强度偏强、脊线偏北、位置较常年同期偏东,西南暖湿气流异常不活跃是造成长治市长时期无降水的主要原因。通过对长治市2008年秋冬季气候要素的描述,分析了大气异常环流造成长治市秋冬季严重干旱的成因,并对秋冬季干旱对农业的影响作了详细分析,提出了干旱应对措施。     

云南安楚高速公路大红田隧道涌水分析

依据大红田隧道水文地质勘察和监测数据,结合前人已有成果,重点探讨隧道涌水特征、涌水影响范围及地下水消失量,并尝试对断流泉出流进行预测。