基于时序InSAR的覆砂石尾矿坝形变演化研究

为解决目前采用在尾矿坝坝体及滩面覆盖砂石进行防尘治理与闭库，但传统监测手段难以实现坝体整体监测的问题，采用时序InSAR技术对2014年10月至2018年7月的Sentinel-1A影像进行处理，提取了对应时间段内卡房尾矿坝的形变信息，并结合实地调查及尾矿坝建设资料，研究了卡房尾矿坝的时序形变演化规律。结果表明:SBAS InSAR监测到坝体出现第1次异常形变加速运动时间与坝体开始铺设砂石工程的施工时间节点完全吻合，体现SBAS InSAR技术在受人为工程影响的坝体形变监测方面具有极高的敏感性。坝体在施工结束后，坝体形变加剧趋势并未缓解，并且出现2次加速现象，分析认为是由于在坝体铺设约2 m厚的碎砂石极大地增加了坝体荷载，打破了坝体原有的应力平衡状态，且识别出雨季对坝体形变影响显著，表明铺设砂石会使得降雨在坝体中的停滞时间加长，进一步引发非雨季期间坝体形变加剧。研究结果不仅能还原坝体出现异常形变的时间与演化过程，而且还可以对引起异常形变的内在影响因素进行分析与论证，对指导尾矿坝灾害识别、分析与治理具有重要的指导意义。     

川西气田地层水回注选井选层研究

根据川西气田的实际情况,对致密砂岩层回注选井选层技术进行研究,初步建立了致密砂岩层回注选井选层技术,优选出川西气田1、2、3号等5个回注井区。目前,注水规模300m3/d,累计注水量达75 698.8m3,节约生产成本约200万元,且有效缓解了高浓度氯离子地层水外排带来的环保压力。现场回注试验表明:致密砂岩层回注高浓度氯离子地层水是可行的,回注选井选层技术具有现场推广应用价值。     

华南地区几种常见岩性的水土流失成因与治理措施研究

华南地区是我国经济相对比较发达的地区，随着人口的增长和区域开发进程的加快，水土流失问题日益严重。本文提出了华南地区常见的四种产生水土流失的岩性（花岗岩、石灰岩、紫色砂页岩和红色砂砾岩），并在分析了其产生水土流失的原因的基础上，提出了治理每种岩性水土流失的具体措施。     

GEOHYDROLOGY AND HYDROCHEMISTRY OF THE DAKOTA AQUIFER,CENTRAL UNITED STATES1

ABSTRACT: The Dakota aquifer, composed of the Dakota Sandstone and stratigraphically equivalent sandstone units of Cretaceous age, is the upper-most regional aquifer underlying the extensively developed High Plains aquifer of the midwestern United States. The concentration of dissolved solids in ground water of the Dakota aquifer ranges from less than 500 milligrams per liter in calcium bicarbonate type water in the eastern outcrop area to more than 100,000 milligrams per liter in sodium chloride type oilfield brine in the Denver Basin to the west. Preliminary maps showing the distribution of dissolved solids confirm the complex nature of the Dakota aquifer as inferred from stratigraphic and hydraulic evidence. Extensive vertical leakage through confining layers, local recharge at the truncated eastern boundary, and a barrier to recharge along the western edge of the Denver Basin are consistent with the distribution of hydraulic head and dissolved solids.     

砒砂岩区不同留茬高度及坡向下沙棘根系分形特征

为提高内蒙古砒砂岩区沙棘(Hippophae rhamnoides)人工林根系的生长能力,对东(E)、南(S)、西(W)、北(N)不同坡向沙棘植株进行了距地表0、10、15、20 cm(即a、b、c、d)留茬高度处理,而根系分形特征是植物根系构型应对环境异质性的表型可塑性,为反映沙棘根系对不同坡向不同留茬生长环境的适应结果,基于分形理论在砒砂岩区对东、西、南、北不同坡向下留茬后的沙棘人工林的全根、主根、一级侧根及二级侧根分形特征以及根系和土壤含水率关系进行研究,以未平茬沙棘为对照(即e)。结果表明,(1)不同坡向相同留茬下沙棘根系分形维数(D)变化为E>N>W>S;土壤含水率为E>N>W>S,这与根系分形维数变化规律一致。(2)相同坡向不同留茬下沙棘根系分形维数(D)变化为c(留茬15 cm)>b(留茬10 cm)>a(留茬0 cm)>d(留茬20 cm)>e(未平茬)。(3)不同坡向不同留茬下沙棘根系各级分形维数变化为D3(二级侧根)>D2(一级侧根)>D1(主根),且D3与D呈显著正相关。(4)在相同坡向不同留茬下土壤含水率变化为:c相似文献   

高温后砂岩抗拉强度及应变场演化实验研究

为研究高温后砂岩的抗拉力学特性及变形破坏规律，对不同温度作用后的砂岩进行巴西劈裂实验，同时采用数字散斑相关方法对砂岩变形破坏进行监测。研究表明:高温作用后砂岩质量损失率增加，波速整体呈降低趋势，砂岩物理特性出现一定劣化；高温作用使砂岩抗拉强度呈先增加后减小的趋势，25~400℃增大了16.08%，400~1 000℃减小了69.30%，砂岩表现为脆性破坏特征；砂岩劈裂过程中，水平应变场演化过程为:局部小变形产生、扩展→小变形区域聚集、合并、连接→应变局部化带产生→应变局部化带扩展并贯穿→宏观劈裂破坏；随着温度升高，应变局部化启动水平先增加后降低，400℃为转折点。该研究方法可为煤矿火灾安全等领域提供借鉴。     

疏松砂岩油气藏出砂风险及机理离散元分析*

为了进一步了解疏松砂岩储层开发过程中的出砂机理，基于PFC3D平台构建离散元模型用于分析疏松砂岩储层出砂风险，探究生产压差等因素对地层出砂的影响。结果表明:较高生产压差下地层流体流速较快，流体对砂粒的拖曳力较大，出砂较严重，生产压差为4.5 MPa时出砂量比3.0，1.5 MPa分别高34.86%和75.45%；地层流体黏度的升高会降低其对砂粒的拖曳，一定程度上减弱出砂程度，流体黏度在1 000 mPa·s时出砂量比100，10 mPa·s下分别低42.50%和54.27%；较大地应力差异条件下砂粒间相互作用较强，砂粒更易脱离岩石骨架而出砂，地应力差异系数为1.75时出砂量是1.25时的2.51倍；另外，内聚力较低的储层砂粒间黏聚力较低，相同生产条件下更易出砂。研究结果可用于预测疏松砂岩储层出砂及定制防砂方案。     

Conservation for the landscape ecological diversity in Wulingyuan scenic area of China

Wulingyuan is located at the mountainous area of the middle reach of the Yangtze River,it is one of the three nature heritages in China which ranks in the “List of Worls‘s Heritage”by UNESCO.It is characterized by quartz sandstone peaks landform with several landform components(pattern,corridor)and rich in landscape ecological diversity and biodiversity.The main patterns(ecosystem)include mid-height mountain peaks,rift-avlley and streams among peaks,peaks and gullies on slopes,square mountain-platforms and peaks among blind valleys and so on.The corridor system consists of natural corridors and artificial corridors among which the stream corridors account for a major part.The fracturing of habitat is unfavorable for the biodiversity conservation,but meanwhile the habitat diversity leads to an increase in biodiversity.Therefore,it is still rich in landscape ecological diversity in Wulingyuan.The biodiversity at the level of landscape component(ecosystem) and the function of the Wulingyuan complex ecosystem,and the measures for the biodiversity conservation in Wulingyuan ecotourism area are discussed in this paper.     

Oxidative dissolution of uraninite precipitated on Navajo sandstone

Column and batch experiments were conducted with sandstone and ground water samples to investigate oxidation of uraninite precipitated by microbially mediated reduction of U(VI), a contaminant in ground water beneath a uranium mill tailings site near Tuba City, AZ, USA. Uraninite precipitated together with mackinawite (FeS_0.9) because Fe(III) from the sandstone and sulfate, another contaminant in the water were reduced together with U(VI). After completion of U(VI) reduction, experiments were conducted to find out whether uraninite is protected by mackinawite against reoxidation. Uncontaminated ground water from the same site, containing 7 mg/l of dissolved oxygen, was passed through the columns or mixed with sandstone in batch experiments. The results showed that small masses of uraninite, 0.1 μg/g of sandstone, are protected by mackinawite from reoxidation. Uraninite masses on the order of 0.1 μg/g correspond to U(VI) concentrations of 0.5 mg/l, typically encountered in uranium contaminated ground waters. Mackinawite is an effective buffer and is formed in sufficient quantity to provide long-term protection of uraninite. Uranium concentrations in ground water passed through the columns are too low (4 μg/l) to distinguish between dissolution and oxidative dissolution of uraninite. However, batch experiments showed that uraninite oxidation takes place.     

世界自然遗产─武陵源

武陵源，位于湖南省西北部张家界市与慈利县、桑植县交界处，方圆３６９ｋｍ~２，由张家界、天子山、索溪峪、杨家界、茅岩河、九天洞、天门山等景区组成。１９８２年，张家界被命名为我国第一个国家森林公园。１９９２年，武陵源（主要包括张家界、天子山、索溪峪）被联合国教科文组织作为世界著名的旅游胜地列入世界自然遗产名录。