胶东—鲁南榴辉岩带的岩石学矿物学地球化学及其成因研究

本文报道了笔者对分布于山东荣成、文登、威海、青岛、胶南、诸城、日照和莒南等地的榴辉岩所作的岩石学矿物学和地球化学研究。确定了这一巨型榴辉岩带是由两条相互重合的榴辉岩带所构成;一条为高温高压成因的A—B类榴辉岩带;另一条为低温高压成因的C类榴辉岩带。它们形成于早元古代早期华南陆块向华北陆块的俯冲,并经受了早元古代角闪岩相变质作用的迭加。早元古代早期华北陆块发生向南运动的大陆推覆体构造,使两种不同成因类型的榴辉岩带在空间上重迭。最后推测这一榴辉岩带的分布代表着我国东部华北陆块与华南陆块的分界界限。     

青岛榴辉岩相变质古洋壳的特征及其成因

利用电子探针等方法研究了青岛榴辉岩相变质古洋壳(蛇纹岩、C类榴辉岩和基性糜棱岩)的岩石学和地球化学特征。确定了它们为华南陆块与华北陆块拼合前的古洋壳,当其俯冲于华北陆块之下时在深部发生碱质交代及低温高压变质作用(C类榴辉岩相)。     

胶东—苏北构造带特征及动力学演化

提出胶东—苏北构造带以广泛出露榴辉岩和超基性岩、普遍发育韧性剪切带和糜棱岩带为特征,具混杂岩特点。它经历了早元古代大陆推覆构造事件(2000～2400Ma)、早元古代末低角闪岩相变质热事件(1800～2000Ma)和元古代末大陆推覆构造事件(6O0～800Ma)。该构造带是华北陆块与华南陆块之间的过渡带。     

青岛C类榴辉岩的岩石学矿物学及其地质意义

本文利用X荧光光谱定量分析、电子探针分析和X衍射分析对青岛C类榴辉岩作了岩石学、岩石化学和矿物化学研究,计算了青岛C类榴辉岩的成岩温度、压力条件及古地温梯度,最后提出了其成因是早元古代早期华南陆块向华北陆块俯冲时,大洋碱性橄榄玄武岩在低温高压环境发生变质作用形成C类榴辉岩和蓝闪石片岩。早元古代的变质作用使C类榴辉岩平衡温度升高,蓝闪石片岩消失。     

胶东—苏北古碰撞带三相变质作用

本文报道了胶东—苏北古碰撞带附近存在的高温低压变质的麻粒岩相、高温高压变质的A—B类榴辉岩相和高压低温变质的C类榴辉岩相三种变质相系,以及与高温低压麻粒岩相有关的Ⅰ型花岗岩带,它们在空间上相协调,在时间上相一致。其经历了早元古代早期的华南—华北陆块碰撞事件、早元古代角闪岩相变质事件和早元古代末期大陆推覆构造事件,使得高温低压麻粒岩相岩石发生退变质作用,低温高压C类榴辉岩相岩石发生进变质作用,蓝闪石片岩消失,并导致高温高压的A—B类榴辉岩相和高压低温的C类榴辉岩相在空间上相叠置。     

鲁苏榴辉岩套的特征及其动力学演化

鲁苏榴辉岩套以广泛分布各类榴辉岩、密切伴生石榴石橄榄岩、石榴石麻粒岩等高压岩石组合 ,普遍发育韧性变形带 ,大量出露燕山晚期碱性花岗岩及深源脉岩为特征。它已经历三迭纪早期华南陆块与华北陆块的碰撞事件、大陆逆掩推覆构造事件及后期白垩纪早期开始的大陆伸展构造事件 ,是我国华南陆块与华北陆块之间的重要过渡单元。     

胶南构造混杂岩带中糜棱岩的显微形变特征与古构造环境——来自榴辉岩围岩的构造信息

以胶南构造混杂岩带中榴辉岩的围岩——套程度不同的糜棱岩化岩石为研究对象,重点研究了其显微形变的结构特征及环境意义、石英组构特征及动力学信息,并讨论其形成的古构造环境和构造机制。     

南黄海千里岩岛榴辉岩的矿物化学及成因探讨

南黄海千里岩岛地处中国华南板块与华北板块缝合线位置,其基底由强烈韧性变形的构造片麻岩组成,并出露具重要大地构造标型意义的超高压榴辉岩类岩石。本文通过对南黄海千里岩岛榴辉岩中主要造岩矿物石榴石的矿物化学研究,探讨了榴辉岩的成因。研究表明,千里岩地区高压变质岩是由于华北与华南两大陆块拼合时,处于其间的岛弧拉斑玄武岩沿碰撞带下插到华北陆块之下,从而使千里岩地区发生高压变质作用,形成了榴辉岩和片麻岩等,后期的构造折返使其上升到地壳上部。     

辽西地区太古宙—古元古代岩石组合及其研究进展

辽西地区是华北克拉通东部陆块的一部分,大面积出露了太古宙—古元古代的古老岩石,是研究华北地壳早前寒武纪演化的重点地区之一。辽西地区太古宙岩石组合以TTG质和花岗质变质深成岩为主,少量变质表壳岩以包体或构造残片形式赋存在变深成岩中;古元古代(2.5~1.6Ga)岩石组合包括长城系裂谷沉积岩和碱性侵入杂岩。最新的区调成果以及地质—地化数据表明,辽西地区记录的太古宙岩浆—变质事件主要集中在约2.55~2.50Ga之间,其形成与洋壳俯冲有关;该区缺乏约2.50~1.85Ga构造—热事件的记录,约1.72~1.70Ga是该区另外一期强烈的岩浆活动,其形成与华北东、西部陆块最终碰撞(约1.85Ga)之后的构造伸展有关。     

榴辉岩套的类型及其地质意义

根据全球榴辉岩的分布、相关岩石组合、成岩物理化学条件和区域构造特征,将榴辉岩套分为两种类型:1)高温榴辉岩套(H型),形成于陆—陆碰撞造山带下部的高温超高压环境,是陆壳俯冲—推覆构造作用的标志;2)低温榴辉岩套(L型),形成于洋—陆碰撞带下部的低温高压环境,是洋壳俯冲—推覆构造作用的标志。     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Estimation of Sediment Properties during Benthic Impact Experiments

Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.     

A Tidal Flow Model for the Gulf of Kachchh, India

A vertically integrated model has been used to study the tidal circulation and currents in the Gulf of Kachchh along the west coast of India. The model is fully nonlinear and uses a semiexplicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model is forced by prescribing the tides along the open boundary of the model domain. The flow is simulated both with and without the presence of the proposed tidal barrage across the Hansthal Creek in the Gulf of Kachchh. The results show a considerable change in the behavior of the tidal flow in the presence of the barrage.     

利用中国GF-3卫星SAR和HY-2A卫星微波散射计的首次台风联合定量观测

<正>The typhoon,as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall,is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia.It can be easily detected by space-borne sensors operated at microwave,visible or infrared bands(Liu et al.,2014).Synthetic Aperture Radar(SAR)is     

离子交换—原子吸收光谱法测定海水中痕量铜、铅、锌、镉、铁、锰

本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8％之间,回收率为90—102％。     

Biogeochemistry of Mangrove Soil Organic Matter: a Comparison BetweenRhizophoraandAvicenniaSoils in South-eastern Brazil

Soil core samples fromRhizophora mangleL. andAvicennia schauerianaStapf & Leech forests from south-eastern Brazil were analysed for their total organic matter content and their sugars, amino acid and amino sugars composition. Organic carbon and nitrogen contents were higher inAvicenniathan inRhizophorasoils. The contribution of sugars and amino acids to the total organic carbon pool was constant with depth inRhizophorasoils whereas inAvicenniasoils it increased. Spectral distribution of sugars and amino acids showed a dominance of Ca-affine monomers, particularly acidic amino acids, and the sugar arabinose. Biogeochemical indicators derived from ratios of individual sugar and amino acid monomers confirm previous studies which showed that organic matter in both soils is mainly of mangrove origin. The results further suggest accumulation of organic matter inRhizophorasoils and a continuing degradation of organic matter inAvicenniasoils. The latter may thus release more nutrients to adjacent ecosystems thanRhizophorasoils.     

A review of orange roughy Hoplostethus atlanticus fisheries,estimation methods,biology and stock structure

Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at 22 – 40 years), and to have exceptionally low natural mortality (M = 0.045–0.064 year^?1) and slow growth rates (K = 0.055–0.070 year^?1). In addition, they spawn large eggs and have low fecundity. These factors combine to make orange roughy highly susceptible to overfishing; most stocks are below 30% of pristine levels. Assessments are obtained from indices of catch rate and trawl, acoustic and egg surveys. Acoustic estimates are the most direct, but are confounded by the species' low target strength (?50 to ?53 dB)–attributable to the wax-filled swim bladder. Extracellular wax esters are stored in abundance and comprise mostly mono-unsaturated fatty acids, with low concentrations of the ω-3 fatty acid family. This unusual composition (resultant from the species' diet) ensures neutral buoyancy. Stock separation has been inferred mainly from biological studies, but genetic studies have also found differences among stocks within New Zealand and Australia. Deep-water habitat may be damaged by trawling operations and may take many years to recover, so in some quarters there is a call for a portion of suitable habitat to be set aside for preservation. Although Namibian orange roughy are shallower, smaller and younger than those in other stocks, the Namibian fishery sustained high catches for only a few years before quotas were reduced, from 12 000 to 1 875 tons. Three management lessons are suggested for developing orange roughy fisheries based on the Namibian experience: (1) imposition of catch limits during exploratory fishing; (2) starting the acoustic surveys earlier in the fishery, if possible; (3) greater reliance on trends in catch rate until a survey series has been established.