利用GPS观测结果研究华北地区现今构造应力场

根据１９９２年和１９９５年两期ＧＰＳ测量结果所获得的位移场和应变场,结合丰富的地质资料,利用有限元方法对华北地区现今构造应力场进行了数值模拟。计算结果表明：华北地区现今构造应力场主压应力方向为ＮＥＥ,其边界力除受ＮＥ５５°～ＳＷ２３５°方向的压应力作用外,同时还受到ＳＥ１２０°～ＮＷ３００°方向的拉张力作用,其中ＮＥ－ＳＷ的压应力量值较大,约为ＳＥ－ＮＷ向拉应力的两倍,这个结果与震源机制解所获得的应力场方向基本一致。这一应力场状态是两种动力学过程的叠加：一是印度板块和太平洋板块的挤压,其中来自印度板块的作用力最大,约为太平洋板块作用力的１．５倍;另一个是因地幔隆起而产生的ＮＷ－ＳＥ向的水平拉张力。     

红河断裂的GPS监测与现代构造应力场

中德合作于１９８８年和１９９１年两次用ＧＰＳ监测滇西地震预报实验场场区现代构造运动及红河断裂的地壳形变,两期观测的数据处理结果表明,滇西ＧＰＳ观测基线相对定位精度接近１０－７。利用两期观测资料得到的基线变化,并结合构造应力场应变模型,估算得到场区近期构造应力场的应力特性参数,结果表明：该地区应力状态以挤压为主,兼有拉张及右旋剪切,其主压应力方位为Ｎ１７°±１２°Ｅ;由于印度板块在场区西侧的侧向挤压作用,场区内北东向压应力占优势。     

江汉盆地钻孔测井资料确定地应力最大水平主压应力方向

利用钻孔测井资料并运用地层倾角测量信息分析法，给出了江汉盆地地应力最大水平主压应力方向为ＮＥ６０～６５°     

长江三峡及邻区构造应力场和震源错动类型的研究

在文献［３］提出的用计算机确定震源断层面解的基础上，进一步给出了解的置信度。置信度由两个因子组成（Ｃ_１，Ｃ_２）。其中Ｃ_１为初动符号的符合比，Ｃ_２为解的不可变动空间与全部空间的比。使用长江三峡及邻区（北纬２８°－３４°，东经１０８°－１１４°）１９７４年以来的初动观测资料，确定了Ｍｓ≥２．１的４０次地震的断层面解、该区的区域应力场和分区应力场及平均错动性质。此外还给出了黄陵背斜地区的应力场特征。结果表明，黄陵背斜的地震构造活动具有整体性，构造过程发生在１５～２０ｋｍ的深度，张应力轴的方向分布显示以背斜为中心的幅射状态。     

苏鲁皖地区现今地壳垂直运动及郯庐断裂带的活动特征

根据苏鲁皖地区１９５３～１９９５年多期精密复测水准资料，以及地质地貌构造背景，研究了苏鲁皖地区的地壳垂直运动及郯庐断裂中南段现今的活动特征，获得如下结论：（１）横穿本区的郯庐断裂带的活动直接控制着本区的构造活动；（２）郯庐断裂的活动特征为张压交替；（３）约自１９５３年开始，苏鲁皖地区地壳运动的演化顺序为张→压→张→压；新的“压”性运动约始于１９９３年，目前正在加强；（４）郯庐断裂带近期运动性质为左旋走滑；（５）张、压运动并不处于同一方向上（彼此相差约４５°）。     

柴北缘锡铁山铅锌矿床构造变形特征及其地质意义

锡铁山铅锌矿床位于柴达木盆地北缘，是我国西北地区重要的有色金属矿床之一。系统的地表调查和坑道编录表明，矿区不同岩石单元构造变形及力学特征不同，既有赋存于滩间山群绿片岩内部的早期深层次韧性－韧脆性变形构造，也有赋存于滩间山群原ｃ岩组紫红色砂岩中的晚期浅层次脆性变形构造。结合区域上柴北缘造山带构造演化事件时间序列以及矿区构造特征的分析表明，韧 性－韧脆性变形构造与陆－陆深俯冲碰撞造山作用及俯冲板片的折返有关，矿区浅层次脆性变形应形成于滩间山群原ｃ岩组紫红色含砾砂页岩沉积之后。应力场恢复显示早期韧性－韧脆性变形构造形迹的主应力σ１ 方向主 要 为 ＮＥ／ＮＥＥ－ＳＷ／ＳＷＷ 方 向，倾角 为５°～ ６０°，表明矿区早期变形阶段具有 ＮＥ／ＮＥＥ－ＳＷ／ＳＷＷ 向近水平挤压、左行走滑、斜向逆冲的性质；而晚期脆性变形恢复的主应力方向有２个，锡铁山沟地区表现为ＥＷ 方向，无名沟－中间沟地区为 ＮＷ－ＳＥ方向。对不同中段控矿断裂构造形成时的主应力状态恢复结果显示 ＮＷ 向断裂构造主应力σ１ 状态为 ＮＥ－ＳＷ 向，显示压扭性逆冲－走滑断层性质，而 ＮＥ向断裂构造主应力σ１ 状态为 ＮＷ－ＳＥ向，显示张扭性正－滑断层性质，分别为上述早期和晚期变形应力场的产物。锡铁山矿体分布受控于左行逆冲和左行滑覆构造运动，矿区北西部成矿较为有利，成矿后的 ＮＥＥ－ＥＷ 向断层左行运动对矿体产生破坏作用，导致西侧矿体南移，东侧矿体北移。      

北京地区八宝山-黄庄-高丽营断裂的活动与地震

根据八宝山-黄庄-高丽营断裂第四纪地质构造活动特征和利用首都圈地区跨断层位移最新的观测资料求得的北京地区区域主压应力方向和区域构造活动特征。分析了八宝山-黄庄-高丽营断裂上7处跨断层位移测点的断层活动与地震活动的关系,得出了首都圈及邻近地区即将进入下一个地震活跃期的结论。认为：1）跨断层位移观测资料能够直接反映区内主要断层的最新活动情况;2）断层现今活动与地震活动在时间序列上相互对应,均有活跃期与平静期相互交替出现的活动特征;3）断层活动强弱是区域主压应力强弱的表现,亦是孕震强度的标志。     

张北-尚义6.2级地震(1998-01-10)前倾斜与地电阻率前兆异常

１　前言１９９８年１月１０日张北－尚义Ｍｓ６．２级地震（λＥ１１４．３°,φＮ４１．１°）,是继１９８９年大同－阳高Ｍｓ６．１地震后,发生在华北北部地区的又一次６级以上强震。距离震中区１１０ｋｍ的内蒙古自治区宝昌地震台的ＳＱ－７０水平摆倾斜仪和地电阻率在震前均观测到明显的前兆异常。尽管在此次张北－尚义地震前,根据某些测项的异常变化,作出了一定的预报,但从整体来讲,并未作出准确的短临预报。因此,对宝昌地震台（λＥ１１４°１５′,φＮ４１°５６′）的主要前兆测项,即ＳＱ－７０地倾斜和地电阻率在张北地…     

主应力方向与大小对断层水平活动影响的计算

计算发现,主应力方向和大小不同时,断层活动的方式不同,与主应力方向交角(θ_0)为65.2°至61.3°(β_0为24.8°至28.7°)时,断层克服摩擦阻力而滑动所需差应力△σ_0最小。△σ值越大,可滑动的断层范围(△θ=θ_1-θ_2)也越大。θ_1与θ_2以θ_0为对称,其极限为40.4°和90(β的极限为49.6°和0°)。接近或大于此极限值的断层是地震破裂断层。北京附近的这类断层是八宝山断层和南口——孙河断层,它们是重点监视目标。     

秭归龙会观5.1级震区及其邻区新生代以来的地壳应力场特征

为了研究三峡坝库区的地壳稳定性，根据奥陶－侏罗纪地层中构造变形的实际观测资料，计算了秭归龙会观５．１级震区及其邻区新生代以来区域应力场的主应力方向。结果表明：主压应力为北东东向，主张应力为北北西向；现代构造应力场与新生代以来应力场基本一致；晚第三纪以来，该区构造应力场相对稳定和统一。     

Preliminary study on plasma membrane fluidity of Psychrophilic Yeast Rhodotorula sp.NJ298 in low temperature

The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.     

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正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose     

JOURNAL OF OCEAN UNIVERSITY OF CHINA

<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail     

Information for Authors

<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo-     

Hydraulics and Hydrology in Mountain Areas

<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a     

Sea ice thickness measurement in spring season in Bothnian Bay using an electromagnetic induction instrument

As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.     

Thermohaline structure inhomogeneity associated with polynia at the northern margin of Emery Ice-shelf

Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.     

Phylogenetic analysis of cultivable bacteria isolated from Arctic sea-ice

Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.     

Information for authors

正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied