Vestiges of the Kerguelen Mantle Plume in Southern Tibet:Evidence from 123–117 Ma Magmatism in the Dingri Area of the Central Tethys Himalaya

The widely distributed Early Cretaceous magmatism in the Tethys Himalaya(TH) of southern Tibet is related to the Kerguelen mantle plume. Associated magmatic activity products are distributed in the eastern TH, where the active age is earlier than the peak ages of the Kerguelen mantle plume. This study investigated magmatic activity of the Dingri area in the central TH which was coeval with the Kerguelen mantle plume. The intrusion in the Dingri area contains diabases and monzonites. The zircon a...     

水平井分段完井不同分段模式优化研究

运用势的叠加原理和镜像反映原理,导出了水平井任意分段模式下井筒与油藏渗流耦合产能计算模型,用该模型可以计算任意分段模式下来平井的产能,通过对比不同分段模式下的水平井产能,可以对分段进行优化,从而指导分段完井方案的制定.研究结果表明:当打开程度一定时,不同分段模式对产量影响不大;产量随着打开程度的提高而增加,但当打开程度大于40％时,产量增幅趋于平缓,因此,打开程度必须大于打开临界程度,这样既减小了因分段而牺牲的产量又达到了分段的目的;井筒摩阻对产量影响较大,在进行分段优化时,必须考虑井筒摩阻的影响,从而优选盲管段的位置.     

海上多子阵立体组合气枪震源优化设计

应用气枪震源子波模拟软件,针对海上常用的6子阵,进行了不同气枪阵列组合情形下的震源子波模拟试算,提出了适应深水区地震勘探要求的立体阵列组合和交错排列组合的气枪阵列.子波模拟试算结果表明,多子阵立体阵列的设计能优化震源子波,同时,将传统的子阵列排列改成交错排列,将气枪阵列的大容量气枪放置在子阵中间位置可以明显提高子波性能,为深水区复杂地质结构条件下的震源设计参数优化提供理论依据.     

Compositional fractionation of polyaromatic hydrocarbons in the karst soils, South China

This study aims to explore the condensation and fractionation trends of persistent organic pollutants (POPs) in the karst soils. The tiankeng is a karst surface expression that can act as a focal point for introduction of contaminants to a karst aquifer, which may serve both as condenser for vapor phase POPs and as barrier/sink for particulate associated less volatile POPs. The fractionation of POPs in soils from the upper rim and floor of tiankeng is of interest in understanding the role of tiankeng in the long-distance transport of POPs. In the present study, polycyclic aromatic hydrocarbons (PAHs) in the surface soils from the upper rim and floor of Dashiwei tiankeng in Southern China were analyzed. The total PAH concentrations in soils were 23.40–190 ng g⁻¹, with phenanthrene being the most abundant. The distribution patterns of PAH compounds in the soil samples matched well with their properties. It indicated the heavy PAHs were susceptible to retention by the floor soils of tiankeng than light PAHs. A plot of Cfloor/Crim against PAH molecular weight gave a good positive relationship in the molecular weight range of 152–276. It is suggested that the floor soils can be focal points of more concentrated PAH and deserve attention. The concentrations of total PAHs in the floor soils (43.40–190 ng g⁻¹, mean 87.76 ng g⁻¹) were higher than those in the upper rim (23.40–88.94 ng g⁻¹, mean 57.74 ng g⁻¹). In addition, there was a shift in compound pattern with an increase in the proportion of light PAHs (2–3 rings), a decrease in heavy PAHs (5–6 rings) and a relatively stable content of 4-ring PAHs. A combination of particulate scavenging and cold condensation is proposed as the major mechanism for the compositional fractionation of PAHs in the soils from the upper rim and floor of tiankeng.     

北祁连东段冷龙岭地区毛藏寺岩体和黄羊河岩体的岩石成因及其构造意义

文中研究了北祁连东段冷龙岭地区毛藏寺岩体和黄羊河岩体的年代学、地球化学和Sr-Nd同位素组成。毛藏寺岩体主要岩石类型为花岗闪长岩。锆石U Pb定年获得花岗闪长岩岩浆结晶年龄为（424±4） Ma。花岗闪长岩具有高的Mg#（约55）,K2O/Na2O=0.77~0.91,A/CNK=0.92~0.94,表明岩石属准铝质。在微量元素组成上,花岗闪长岩富集LILE、亏损HFSE,轻重稀土分异明显［(La/Yb)N=16.9~19.5］,具有弱的Eu负异常（Eu/Eu*=0.75~0.83）;花岗闪长岩具有ISr=0.706 3~0.706 5,εNd(t) =-1.5~-1.1,TDM=1.10~1.16 Ga。这些地球化学特征和Sr Nd同位素组成表明,花岗闪长岩岩浆源区为基性下地壳变玄武质岩石,但在成岩过程中有少量幔源物质的加入。黄羊河岩体主要由钾长花岗岩组成,其岩浆结晶年龄为（402±4） Ma。岩石富碱（K2O+Na2O=6.91‰~7.66%）,K2O/Na2O>1,A/CNK=0.97~1.05。钾长花岗岩富集LILE及HFSE,轻重稀土元素分馏中等［(La/Yb)N =10.6~17.8］,并具有明显的负Eu异常（Eu/Eu*=0.43~0.68）,表明钾长花岗岩具有铝质A型花岗岩的地球化学特征。钾长花岗岩具有ISr=0.710 3~0.711 3,εNd(t)=-6.7~-6.0,TDM=1.46~1.55 Ga,反映岩浆主要来自地壳中长英质物质的部分熔融。冷龙岭地区花岗岩类的岩石成因及其岩浆演化揭示了北祁连山造山带从加里东早期的挤压构造体制向加里东晚期的伸展构造体制的演化。这些花岗岩类形成于碰撞后构造背景,岩浆的产生可能与俯冲的北祁连洋板片的断离作用有密切联系。     

基于ET技术的水权分配

通过研究减少蒸腾蒸发（ET）,来达到“真实”节水,以馆陶县为例,通过计算馆陶县ET值,利用ET技术进行水权分配。为以后馆陶县水资源开发利用和保护提供理论数据,对水资源的可持续发展具有重要的现实意义。     

无外加流体、350℃和差异应力条件下硫化物再活化实验研究

红透山块状硫化物矿石主要成分为黄铁矿、磁黄铁矿、黄铜矿、闪锌矿和石英、角闪石、黑云母等脉石矿物。将此矿石烘干后作为试料置于岩石三轴应力试验机,在13h内将轴压、围压和温度分步升至1276MPa、414MPa和350℃,然后在空气中自然冷却至室温。实验产物中黄铁矿、石英、长石等以脆性碎裂为主,而磁黄铁矿、黄铜矿、闪锌矿和云母等以塑性变形为主。再活化的黄铜矿、磁黄铁矿和少量闪锌矿呈脉和网脉穿插黄铁矿碎斑。实验结果表明,即使没有外来流体加入．构造动力作用所导致的流体包裹体破坏所释出的流体,就足以使成矿物质发生活化转移和再活化。     

对磺基苯偶氮变色酸分光光度法测定岩石样品中的氟

采用对磺基苯偶氮变色酸分光光度法对岩石样品中氟的含量进行测定。确定的最佳测定条件为:测定波长570 nm,放置2 h后测定,盐酸介质浓度0.84 mol/L,显色剂用量5.0 mL。氟离子浓度在0~1.4 mg/L时符合比尔定律,方法检出限为0.06μg/g。以岩石标准物质代替氟标准溶液制作标准曲线,可有效降低杂质元素的干扰。对国家一级标准物质和日本玄武岩标准物质6次测定的相对标准偏差(RSD)为2.37%~6.32%。     

散体材料桩复合地基极限承载力计算

以土力学及弹塑性理论为基础，分析了散体材料桩的塑性应力分布。推导出了单桩极限承载力和单桩复合地基的极限承载力计算公式。得出了提高桩体材料的内摩擦角和桩周土对桩的径向围限力是提高散体材料桩复合地基承载力的有效途径的结论。给出了工程实例，验证了文中计算公式的实用性。