天山南缘北轮台断裂库尔楚段晚第四纪的最新活动和滑动速侣

使用全站仪实测了天山南麓北轮台逆断裂库尔楚段阿克艾肯-喀腊萨喀腊阿塔木冲洪积扇断层崖地形地貌,采用10Be测年方法测定了该冲洪积扇的形成年龄,得到该断裂段垂直位移滑动速率为0.48 mm/a、0.85～1.0 mm/a和1.52 mm/a,并对该断裂段的水平缩短速率和天山第四纪水平缩短量进行了讨论.     

Permeable Reactive Barrier for the treatment of contaminated surface water in Katedan industrial development area, Hyderabad, India

Permeable Reactive Barrier （PRB） is an emplacement of inert material （s） in the subsurface, designed to intercept a contaminated plume, provides a preferential flow path through the reactive media, and transforms the contaminant into environmentally acceptable forms to attain concentration remediation goals at the discharge of the barrier. The phenomena, which help in remediation within PRB, are adsorption/sorption, precipitation, oxidation/reduction and biodegradation. Various materials like zero-valent iron, zero-valent bi-metals, natural zeolites, organic carbon, fly ash, zeolites, limestone, activated alumina, apatites, etc. have been tried by many researchers to remove organic and inorganic contaminants. In USA, Canada, and many European countries commercial full-scale and pilot scale PRBs are successfully working. The design and installation of full scale PRBs needs laboratory treatability and dynamic flow column experiments？ The concept of PRB is being applied to treat contaminated surface water in the Katedan industrial area, Hyderabad, India. National Geophysical Research Institute （NGRI）, Hyderabad, India, conducted systematic studies in collaboration with Norwegian Geotechnical Institute （NGI）, Norway, to develop PRB technique to decontaminate the surface water pollution due to industrial effluent. A site assessment study in the Katedan Industrial Area, were carried out and water, soil and sediment from the lakes of the area were found to be polluted with high concentrations of heavy metals like As, Pb, Cr, Cd, Ni, etc. Adsorption studies at NGRI with synthetic samples and in-situ industrial effluent using different reactive media for removing contaminants like arsenic, chromium, cadmium, copper, nickel, lead and zinc have been carried out and yielded satisfactory results. The performance of zero-valent iron and limestone is encouraging in removing As,     

Drill cutting accumulations in the Northern and Central North Sea: a review of environmental interactions and chemical fate

The exploration and production of North Sea oil and gas reserves has resulted in the accumulation of large quantities of drill cuttings on the seabed surrounding drill sites. This complex mixture of man-made and natural substances contains higher concentrations of certain metals (Ba, Cr, Cu, Ni, Pb, and Zn) and hydrocarbons than are observed in background sediments. With decommissioning of older platforms underway, an evaluation of the environmental interactions and chemical fate of the drill cuttings accumulations is required.This review concentrates on contaminants within drill cutting accumulations in the Northern and Central North Sea (56 degrees N-62 degrees N). Present literature reviewed reveals that hydrocarbons within the cuttings piles remain relatively unchanged with time. A considerable proportion of the associated contaminants are likely to remain within the cuttings pile unless they are disturbed which will then increase exchanges of porewater and solids back to the seabed surface resulting in pathways of exposure for organisms.     

Effects of hydrocarbon contamination on a free living marine nematode community: results from microcosm experiments

Anthropogenic inputs of crude and refined petroleum hydrocarbons into the sea require knowledge of the effects of these contaminants on the receiving assemblages of organisms. A microcosm experiment was carried out to study the influence of diesel on a free living nematode community of a Tunisian lagoon. Sediments were contaminated by diesel that ranged in concentration from 0.5 to 20 mg diesel kg⁻¹ dry weight (dw), and effects were examined after 90 days. Gradual changes in community structure were revealed depending on the quantity of diesel administrated. In the medium (1 mg diesel kg⁻¹ and 5 mg diesel kg⁻¹ (dw)) and high (10 mg diesel kg⁻¹, 15 mg diesel kg⁻¹ and 20 mg kg⁻¹ (dw)) treated microcosms, most univariate measures, including diversity and species richness, decreased significantly with increasing level of diesel contamination whereas nematode assemblage from the low treated microcosm (0.5 mg diesel kg⁻¹ (dw)) remained unaffected. Results from multivariate analyses of the species abundance data demonstrated that responses of nematode species to the diesel treatments were varied: Chaetonema sp. was eliminated at all doses tested and seemed to be intolerant species to diesel contamination; Pomponema sp. and Oncholaimus campylocercoïdes were significantly affected at all diesel contamination levels but they were not eliminated, these species were categorized as “diesel-sensitive”; Hypodontolaimus colesi, Daptonema trabeculosum and Daptonema fallax which significantly increased respectively at 0.5, 1 and 5 mg diesel kg⁻¹ (dw) concentrations and appeared to be “opportunistic” species at these doses whereas Marylynnia stekhoveni which increased at all high doses (10, 15 and 20 mg diesel kg⁻¹ (dw)) seemed to be a “diesel-resistant” species.     

有限单元分析中的移动边界方法

本文就波动问题提出一种移动边界的有限单元解法。此时模型边界的位置不是固定的,它将随着波前向前推进和退回,以保证在计算时间长度内边界反射波不到达观测点。文中给出了计算边界有效载荷的递推公式,可以简便有效地避免虚假反射波的干扰。为降低运算量和虚模型中的存贮,应适当选取移动间隔,截断误差和移动起点。对于层状模型,若采用直接积分的中心差分方法,计算过程十分简单,也可用于有限差分等方法的计算中。该方法在应用上的限制是对计算机内存量的要求较通常方法为大。     

Indian Monsoon Signals Reflected by the Ratio of Cl- to Na+ in Dasuopu Ice Core From Xixiabangma, Himalayas

INDIAN MONSOON SIGNALS REFLECTED BY THE RATIO OF Cl~- TO Na~ IN DASUOPU ICE CORE FROM XIXIABANGMA,HIMALAYAStheChineseNationalBasicResearchProgramme (GrantG19980 4 0 80 0 )andChineseNationalScienceFoun dation (NSFgrant 4 980 10 0 4 )     

Skilful Forecasts of Summer Rainfall in the Yangtze River Basin from November

Variability in the East Asian summer monsoon(EASM) brings the risk of heavy flooding or drought to the Yangtze River basin, with potentially devastating impacts. Early forecasts of the likelihood of enhanced or reduced monsoon rainfall can enable better management of water and hydropower resources by decision-makers, supporting livelihoods and major economic and population centres across eastern China. This paper demonstrates that the EASM is predictable in a dynamical forecast model from the pr...     

Pb, Sr AND Nd-ISOTOPIC COMPOSITIONS OF PALEO AND NEO-TETHYAN OCEANIC CRUSTS IN THE EASTERN TETHYAN DOMAIN: IMPLICATION FOR THE INDIAN OCEAN-TYPE ISOTOPIC SIGNATURE

Pb, Sr AND Nd-ISOTOPIC COMPOSITIONS OF PALEO AND NEO-TETHYAN OCEANIC CRUSTS IN THE EASTERN TETHYAN DOMAIN: IMPLICATION FOR THE INDIAN OCEAN-TYPE ISOTOPIC SIGNATURE     

TWO SUITES OF OPHIOLITE RECOGNIZED IN THE MAQEN AREA, NORTHEASTERN TIBETAN PLATEAU

TWO SUITES OF OPHIOLITE RECOGNIZED IN THE MAQEN AREA, NORTHEASTERN TIBETAN PLATEAU1　JiangCF ,YangJS ,FengBG ,etal.OpeningandClosingTectonicsofKunlunMountains.Beijing :GeologicalPublishingHouse (inChinese) ,1992 . 2　XuZQ ,YangJS ,LiHB ,etal.TheA’nyemaqenSutureBeltandtheDynamicsinSubductionandCollision .TheStudyoftheOphioliteandGeodynamics[M ].(inChinese) .1996 .185～ 189. 3　YangJS ,XuZQ .TheA’nyemaqenOphioliteBeltEastKunlunMts.,NWChi…