云南剑川新民铁矿地质及成因

新民铁矿位于北北西—南南东向雪龙山—桥后断裂（弥沙河断裂）东侧之云岭褶皱束三级构造单元中,赋矿层位为中三叠统上兰组下亚段泥质灰岩.地层、构造控矿,为沉积—后期改造型铁矿床.     

山西王莽岭国家地质公园地貌景观特征及其成因研究

王莽岭国家地质公园位于太行山南段,地质遗迹资源丰富、类型多样,具有重要的美学及科学价值。本文以王莽岭地质公园为研究区,通过野外调查并依据地质遗迹的成因、形态及规模、自然属性及分布特征,将地质遗迹资源划分为地貌景观、沉积构造、构造形迹、古生物化石四类,系统地研究了峡谷、岩溶、夷平面、河流阶地、瀑布等地貌的成因,为太行山的形成演化研究提供了资料,对提升研究区地质遗迹资源的科学价值具有重要意义。     

新疆赛里木湖的湖滩岩特征、时代及其对 MIS3阶段湖面变化的指示意义

在对西天山赛里木湖盆地进行第四纪地质调查与5万填图基础上,发现沿该湖泊的不同湖岸阶地上都不同程度地发育了可指示湖面变化的湖滩岩。水准测量结果表明,典型的湖滩岩最常见于高出现今湖面7.1~9.4 m和33.4~39.4 m的低、高两级湖积台地上。对湖滩岩样品进行岩石学和矿物学研究进一步揭示,湖滩岩主要由内碎屑、藻团块、陆源碎屑、胶结物和填隙物等构成,胶结物主要为亮晶方解石,夹少量文石,表明赛里木湖周边的湖滩岩为典型的方解石胶结砂屑砾屑岩。湖滩岩样品的U系年代测试结果表明,低、高两级台地上的湖滩岩主要形成于距今24.8±1.5 ka至27.6±1.5 ka和55.4±3.8 ka的晚更新世晚期,大致对应末次冰期间冰阶MIS3阶段早期和末期的相对暖湿气候阶段。湖滩岩及其测年结果指示,赛里木湖最近一期最高湖面出现在距今55.4 ka左右末次间冰阶早期,其后由于气候的干旱化,湖面整体处于逐步下降过程,在相对暖湿期间经历了多次湖面相对稳定期并形成湖滩岩。     

浅谈利用Google Earth结合MapGis软件制作地形图方法

利用Google Earth的三维模拟功能,通过不同海拔平面与地表的接触线来获得等高线,结合MapGis的编辑功能即可形成矢量化的地形图。经与实测地形图对比,两者山头、山谷、山脊、鞍部、高程及等高线形态基本相同,可做为野外工作及其它对地形图精度要求不高工作的参考资料。     

The influence of irrigation and Wuliangsuhai Lake on groundwater quality in eastern Hetao Basin,Inner Mongolia,China

Geochemical and isotopic characterization of groundwater and lake-water samples were combined with water and total dissolved solids balances to evaluate sources of groundwater quality deterioration in eastern Hetao Basin, Inner Mongolia, China. Groundwater quality is poor; 11 of 13 wells exceed drinking-water guidelines for at least one health-based parameter and all wells exceed aesthetic guidelines. The well water is largely derived from Yellow River irrigation water. Notably high uranium concentrations in the Yellow River, relative to world rivers, suggest groundwater uranium and other trace elements may originate in the river-derived irrigation water. Complex hydrostratigraphy and spatial variation in groundwater recharge result in spatially complex groundwater flow and geochemistry. Evapotranspiration of irrigation water causes chloride concentration increases of up to two orders of magnitude in the basin, notably in shallow groundwater around Wuliangsuhai Lake. In addition to evapotranspiration, groundwater quality is affected by mineral precipitation and dissolution, silicate weathering, and redox processes. The lake-water and TDS balances suggest that a small amount of discharge to groundwater (but associated with very high solute concentrations) contributes to groundwater salinization in this region. Increasing salinity in the groundwater and Wuliangsuhai Lake will continue to deteriorate water quality unless irrigation management practices improve.     

青海玉树地区活动断裂与地震

青海玉树是巴颜喀拉地块西南边界上的典型历史强震区。最新的活动断裂遥感解译与地表调查结果表明,该区新构造期间主要发育清水河断裂带、玉树断裂带、阿布多断裂带和杂多断裂带4条NW向左旋走滑活动断裂带。其中,构成玉树—鲜水河—小江断裂系尾端构造的玉树活动断裂带是该区活动性最显著的岩石圈断裂。该断裂是由当江断裂、结古—结隆断裂和巴塘断裂3条斜接的主干断层和夹杂其间的多条次级断裂所共同构成的Z型左旋剪切张扭性变形带。它在上新世以来和晚第四纪期间的左旋走滑速率为4.0~5.4mm/a,调节了该区大部分的块体挤出与旋转变形,并构成该区大震活动的主要控震构造。历史强震梳理和古地震研究揭示,玉树主干走滑断裂带自约14530a BP以来至少发生了包括2010年地震在内的共11次大地震,原地重复间隔平均在千年以上,最长达近3000a。1738年玉树西北地震之后,玉树—甘孜断裂带的主干断层表现为平均间隔为50~100a的低频、串联式分段破裂过程,并且大震活动存在从东南向西北迁移的趋势。通过对玉树断裂未来大地震危险性进行综合地质判定认为,该区至少仍存在6段未来百年内大地震危险程度不同的地震空区,潜在的大地震震级为Mw6.6~7.3,其中危险性相对较高的段落主要是当江断裂带的当江—拉则段和结古—结隆断裂带上的结隆—叶卡诺段与桑卡—相古段。     

黔西地区构造变形特征及其煤层气地质意义

黔西地区处于特提斯与滨太平洋两个构造域的交接地带,多期性质不同的构造作用形成了现今错综复杂的构造变形特征。根据构造变形的差异,可划分为织金-纳雍NE向构造变形区、水城-紫云NW向构造变形区和黔西南复杂构造变形区。在野外地质的基础上,结合微观变形特征和矿物流体包裹体测试分析,认为黔西地区构造变形属于上地壳低温-中低温环境下的脆性-脆韧性变形;由于黔西地区基底构造相对稳定,成煤期后断块内部变形较弱,煤储层形成了一定程度的构造裂隙,有助于渗透率的提高,煤层气勘探开发前景良好。     

新郑矿区地热资源潜能分析与保护建议

基于新郑矿区以平均每年0.0813×108m3的涌水量向地表排放热水,造成的地热资源损失和污染环境的现实,在分析地温地质条件基础上,利用热储资源量公式、卡明斯基公式和弹性储存量公式,分别计算了矿山开采前和开采后不同类型地热资源量,并对当前矿区地热潜能进行了评估。在此基础上,提出了选择煤层底板加固技术,保持岩溶裂隙水一定的水位、减少地下水排放和利用识别模型,选择适宜区段作为地热资源开采区,以调减矿山日常的排水量,尽可能维持渗流场基本不变,进而提高热储的潜能,实现节能减排,达到保护与利用地热资源的效果的建议。     

Predicting lake water quality responses to load reduction: a three-dimensional modeling approach for total maximum daily load

Water quality restoration efforts often suffer the risk of ineffectiveness and failure due to lack of quantitative decision supports. During the past two decades, the restoration of one of China’s most heavily polluted lakes, Lake Dianchi, has experienced costly decision ineffectiveness with no detectable water quality improvement. The governments are planning to invest tremendous amount of funds in the next 5 years to continue the lake restoration process; however, without a quantitative understanding between the load reduction and the response in lake water quality, it is highly possible that these planned efforts would suffer the similar ineffectiveness as before. To provide scientifically sound decision support for guiding future load reduction efforts in Lake Dianchi Watershed, a sophisticated quantitative cause-and-effect response system was developed using a three-dimensional modeling approach. It incorporates the complex three dimensional hydrodynamics, fate and transport of nutrients, as well as nutrient-algae interactions into one holistic framework. The model results show that the model performs well in reproducing the observed spatial pattern and temporal trends in water quality. The model was then applied to three total maximum daily load scenarios and two refined restoration scheme scenarios to quantify phytoplankton responses to various external load reduction intensities. The results show that the algal bloom in Lake Dianchi responds to load reduction in a complex and nonlinear way, therefore, it is necessary to apply the developed system for future load reduction and lake restoration schemes for more informed decision making and effective management.     

Quick sulfide buffering in inner shelf sediments of the East China Sea impacted by eutrophication

In the eutrophic coastal ocean, quick formation of iron (Fe) sulfide is environmentally important to effectively prevent accumulation of dissolved sulfide and its detrimental effects on the benthic ecosystem. In this study, 0.5 N HCl-extractable labile Fe (LFe), acid volatile sulfide, and pyrite in the East China Sea inner shelf sediments were examined to investigate the mechanisms of quick sequestration of dissolved sulfide and potential impacts of frequent algal blooms on the capacity of quick sulfide-buffering in eutrophic coastal areas of the large-sized continental shelf subject to massive terrestrial input. The results indicate that sulfate reduction has been competitively suppressed by dissimilatory Fe reduction due to limited availability of labile organic matter. Dissolved sulfide can be quickly buffered by reaction with LFe and, therefore, is difficult to accumulate to a high level. The quick sulfide-buffering capacity has not become exhausted partly because of the formation of un-sulfidized LFe(II) via dissimilatory reduction of less reactive Fe oxides. It is expected that dissolved sulfide will not pose detrimental effects on the benthic ecosystem in the near future if the current biogeochemical/ecological state remains.