东海地区高压-超高压变质带中变质橄榄岩及其原岩和成因类型的判别——以PP1孔和PP3孔为例

本文在总结全球地幔橄榄岩岩石学和地球化学特征的基础上,首次提出了一个用于判别HP-UHP变质带中变质橄榄岩原岩及其成因类型的判别图解.该图主要由镁铁总量MgO+(%)和一个参数m+f/si比值构成.另用Al2O3和CaO分别与MgO+(%)制成两个辅助图解,以示方辉橄榄岩和二辉橄榄岩之间在Al2O3和CaO含量上的分界.通过原岩判别结果和研究表明,PP3孔和PP1孔两者在变质组合、原岩成因类型、地球化学和变质条件方面存在一系列的重大差异.分别代表来自两种极端的地球化学类型和两种不同大地构造环境的UHP变质体.PP3钻孔以Ol+Gt+Cpx+Opx+Sp为变质矿物共生组合的含石榴石纯橄岩,其原岩系来自地幔残余成因的方辉橄榄岩遭受UHP变质作用的产物,它以成分高度均一,富Mg(Mg'=92),极端亏损不相容元素REE(∑REE<1×10-6可称为超亏损型)为特征.在变质相中仍保留原岩的残余矿物铬尖晶石(Sp),其成分显示蛇绿岩地幔橄榄岩的成分趋势.并出现以Gt和Sp共存相为特征的变质相.据实验结果(klemme,2004)表明该共存相的稳定域的P-T条件Cr-Sp可达7Gpa,T1400℃,即形成于200km的地幔深度.综合研究显示该孔变质橄榄岩原岩(方辉橄榄岩)具有大洋岩石圈地幔残余成因的某些印记,而不是同深度原生地幔岩相转变的产物.PP1孔变质橄榄岩是由无水矿物相(Ol+Opx+Cpx+Gt)+含水矿物相(Phl±Chu)组成的石榴石橄榄岩杂岩,其原岩来自两种不同成因的超镁铁岩系列:一为具地幔成因的方辉橄榄岩-二辉橄榄岩系列(可能相当于地幔楔中的Al型橄榄岩),另一部分(少数)来自具岩浆成因的超镁铁岩系列(纯橄岩-异剥橄榄岩-辉石岩组合,可能相当于A2型橄榄岩).该套变质橄榄岩,以成分高度不均一,极端富集REE(∑REE平均>20×10-6可称为超富集型)和大离子亲石元素(K、Ba、Rb)为特征.这种异常现象并不反映其原岩原有的地球化学特征,它可能是由于在俯冲过程中受到陆壳物质的污染,或壳-幔相互作用所致.据该孔变质相中缺乏Sp相,而以Gt为标志的变质相的事实,推断其形成的压力条件应>7Gpa, 即形成的深度应大于200km.上述研究表明在苏鲁UHP变质带中,不仅有来自大陆地幔楔中的地幔残余的UHP变质体,而且首次提出有可能来自大陆俯冲前锋具大洋岩石圈地幔性质的(蛇绿岩型地幔残片)变质体存在,这对揭示该区UHP变质带的形成和演化过程提供了新的信息.     

铬尖晶石和石榴石的相变: 大陆科学钻探CCSD-PP3孔超镁铁岩超高压变质作用的证据

PP3超镁铁岩主要岩石类型有纯橄岩和石榴石橄榄岩,两者为渐变,主要矿物为橄榄石、铬尖晶石、石榴石、单斜辉石和斜方辉石.铬尖晶石的Cr#[Cr/(Cr+Mg) ×100]从51~89变化,TiO₂和MnO₂值分别低于0.26%和0.46%.铬尖晶石矿物表现为4期次演化的特点,反映了从岩浆期、榴辉岩相、角闪岩相和绿片岩相演化特征.随着超镁铁岩的演化,铬尖晶石表现为Cr#不断增大,而Mg#[Mg×100/(Mg+Fe2+) ]不断减少、氧逸度不断增加的过程.PP3铬尖晶石反映了地幔来源,为大陆岩石圈超镁铁岩特征,后期随折返而演化.从石榴石与铬尖晶石相互转变过程看出,PP3超镁铁岩经历了深度加大的过程,超镁铁岩曾经到达100km以上的岩石圈地幔深处.在绿片岩相-绿片角闪岩相变质过程中,铬尖晶石中Cr、Mg和Al减少,Fe相对增加,产生富Cr尖晶石变质作用样式.晚期剪切变形等次生变化影响了铬尖晶石矿物成分.      

东海地区高压-超高压变质带中变质橄榄岩及其原岩和成因类型的判别——以PP1孔和PP3孔为例

本文在总结全球地幔橄榄岩岩石学和地球化学特征的基础上,首次提出了一个用于判别HPUHP变质带中变质橄榄岩原岩及其成因类型的判别图解。该图主要由镁铁总量MgO+（%）和一个参数m+f/si比值构成。另用Al2O3和CaO分别与MgO+（%）制成两个辅助图解,以示方辉橄榄岩和二辉橄榄岩之间在Al2O3和CaO含量上的分界。通过原岩判别结果和研究表明,PP3孔和PP1孔两者在变质组合、原岩成因类型、地球化学和变质条件方面存在一系列的重大差异。分别代表来自两种极端的地球化学类型和两种不同大地构造环境的UHP变质体。PP3钻孔以Ol+Gt+Cpx+Opx+Sp为变质矿物共生组合的含石榴石纯橄岩,其原岩系来自地幔残余成因的方辉橄榄岩遭受UHP变质作用的产物,它以成分高度均一,富Mg（Mg’=92）,极端亏损不相容元素REE（∑REE<1×10-6可称为超亏损型）为特征。在变质相中仍保留原岩的残余矿物铬尖晶石（Sp）,其成分显示蛇绿岩地幔橄榄岩的成分趋势。并出现以Gt和Sp共存相为特征的变质相。据实验结果（klemme,2004）表明该共存相的稳定域的PT条件CrSp可达7Gpa,T1400℃,即形成于200km的地幔深度。综合研究显示该孔变质橄榄岩原岩（方辉橄榄岩）具有大洋岩石圈地幔残余成因的某些印记,而不是同深度原生地幔岩相转变的产物。PP1孔变质橄榄岩是由无水矿物相（Ol+Opx+Cpx+Gt）+含水矿物相（Phl±Chu）组成的石榴石橄榄岩杂岩,其原岩来自两种不同成因的超镁铁岩系列：一为具地幔成因的方辉橄榄岩二辉橄榄岩系列（可能相当于地幔楔中的Al型橄榄岩）,另一部分（少数）来自具岩浆成因的超镁铁岩系列（纯橄岩—异剥橄榄岩—辉石岩组合,可能相当于A2型橄榄岩）。该套变质橄榄岩,以成分高度不均一,极端富集REE（∑REE平均>20×10-6可称为超富集型）和大离子亲石元素（K、Ba、Rb）为特征。这种异常现象并不反映其原岩原有的地球化学特征,它可能是由于在俯冲过程中受到陆壳物质的污染,或壳幔相互作用所致。据该孔变质相中缺乏Sp相,而以Gt为标志的变质相的事实,推断其形成的压力条件应>7Gpa, 即形成的深度应大于200km。上述研究表明在苏鲁UHP变质带中,不仅有来自大陆地幔楔中的地幔残余的UHP变质体,而且首次提出有可能来自大陆俯冲前锋具大洋岩石圈地幔性质的（蛇绿岩型地幔残片）变质体存在,这对揭示该区UHP变质带的形成和演化过程提供了新的信息。     

也谈铙钹寨超镁铁岩体的成因和构造类型的归属问题

铙钹寨岩体是一个遭受角闪岩相一麻粒岩相变质作用改造的超镁铁岩体。由于其变质程度的不均一性，一部分仍保留着原地幔橄榄岩的基本特征（如粗粒，具三联点结构和熔融残余结构的方辉橄榄岩和纯橄岩）。另一部分则表现明显的重结现象，原地幔橄榄岩类的基本特征已部分或全部消失，形成以出现不同数量的新生矿物组合为特征的变橄榄岩类（以细粒变纯橄岩和似斑状角闪方辉橄榄岩为代表）。恢复其原岩，该岩体由纯橄岩（极少）、方辉橄榄岩（为主）和二辉橄榄岩组成。但在纯橄岩一方辉橄榄岩组合与二辉橄榄岩组合两者之间在成分上显示一个明显的间断。前者以贫Al（Al2O3含量〈1％）、Ca（CaO含量〈1％）、Ti（TiO，含量〈0．05％）和富Mg（Mg^#=92—93）为特征。其主要矿物Ol和Opx均属富镁橄榄石（Fo92-93）和顽火辉石（En92～93）。后者则相对富Al（Al2O3含量由3.36％～3．75％）、Ca（CaO含量由2．07％-3．15％）、Ti（TiO2 0．1％～0．12％）和相对低镁（Mg^#=89—90）为特征。其主要造岩矿物Ol和Opx属相对低Mg的镁橄榄石（F090）和顽火辉石（En89～90）。副矿物尖晶石具有多期熔融的复杂成因，但其成分区及趋势显示蛇绿岩地幔橄榄岩所常见的双频分布（bimodal distribution）特征。综合研究表明该两套地幔岩原岩组合代表了不同亏损程度和不同构造环境下多期熔融的地幔残余。以方辉橄榄岩（和少量纯橄岩）为代表，并伴有豆荚状铬铁矿化及其特征的瘤状矿石的产出背景，标志其遭受较高的部分熔融程度，可能代表产于洋内俯冲带之上（Supra—Subduetion zone）亲弧环境的上地幔残余，带有SSZ型蛇绿岩的某些印记。二辉橄榄岩可能代表来自MOR环境下，弱亏损的上地幔残余岩片。故该岩体超镁铁岩不具有大陆地幔橄榄岩的成因性质。     

闽北政和洋后变质超镁铁岩的岩石地球化学及矿物化学研究

岩石化学研究表明，洋后变质超镁铁岩是由变质方辉橄榄岩和变质超镁铁堆积岩组成。变质方辉橄榄岩的微量元素地球化学及矿物化学特征表明，应为亏损的残余地幔产物。通过系统的岩石地球化学、矿物化学及年代学研究，认为洋后变质超镁铁岩可能为华南晚震旦－早古生代的蛇绿岩组成部分。     

南阿尔金巴什瓦克石榴橄榄岩的变质演化

南阿尔金巴什瓦克地区石榴橄榄岩在空间上呈透镜体状与高压基性麻粒岩和含石榴子石长英质片麻岩伴生.基于矿物共生组合关系和变质反应结构特征,并结合矿物化学详细分析以及温压条件的估算,我们将该区石榴橄榄岩的变质演化划分为3个阶段:峰期变质阶段(Ml)、峰后早期退变质阶段(M2)和晚期角闪岩相-绿片岩相退变质阶段(M3).M1阶段的矿物组合为石榴子石(Grt)+橄榄石(O1)+斜方辉石(Opx)+单斜辉石(Cpx),所估算的温压条件为:T=891～ 1054℃、P=17.2 ～24.7kbar; M2阶段以石榴子石周围出现斜方辉石(Opx)+单斜辉石(Cpx)+尖晶石(Spl)的次生边为特征,在P=10kbar时,估算的温度条件为:T=711 ～ 796℃;M3阶段以形成角闪石(Amp)+蛇纹石(Srp)+金云母(Phl)+绿泥石(Chl)+磁铁矿(Mag)±滑石(Tlc)为特征.石榴橄榄岩具有与相邻的长英质麻粒岩和基性麻粒岩类似的P-T演化历史.结合成因矿物学和初步的地球化学特征,我们认为石榴橄榄岩的原岩可能为侵位于大陆地壳的镁铁质-超镁铁质杂岩,并在早古生代与长英质地壳物质一起俯冲,经历高压(超高压?)/高温变质作用以及随后的变质和地球动力学演化.     

苏鲁超高压变质带岗上超镁铁质岩铬尖晶石形成过程——铬成矿新机制

岗上超镁铁质岩主要由纯橄岩和石榴橄榄岩组成,主要组成矿物有橄榄石、铬尖晶石、石榴子石、单斜辉石和斜方辉石等。铬尖晶石的Cr#[Cr/(Cr+Mg)×100]从51到89变化,铬尖晶石矿物表现为4期次演化的特点,反映了从岩浆期向榴辉岩相、角闪岩相和绿片岩相演化特征。随着超镁铁质岩的演化,铬尖晶石中Cr#不断增大(51增大到89),而铬尖晶石Mg#[Mg×100/(Mg+Fe2+)]不断减少,氧逸度不断增加。在绿片岩相—绿片角闪岩相退变质过程中,铬尖晶石中Cr、Mg和Al减少,Fe相对增加,产生富Cr尖晶石变质作用样式。晚期剪切变形等次生变化有利于富铬铬尖晶石矿物的形成和铬尖晶石的富集。同时,角闪岩相和绿片岩相变质作用使铬尖晶石富集呈现容易开采的条带状,降低了铬尖晶石与其他硅酸盐矿物的结合强度,降低了开采强度和成本,使原本不易于开采的铬铁矿矿体变得可以开采。这些意味着铬铁矿矿体展布要结合后期变质作用进行综合分析。     

中国大陆科学钻探工程卫星孔CCSDPP6钻孔橄榄岩岩石学研究

中国大陆科学钻探工程卫星孔PP6钻孔位于苏鲁超高压变质带的山东荣成滕家集马草夼橄榄岩体中。该橄榄岩出露于元古代花岗闪长片麻岩中,面积为300m×130m。地表岩石风化强烈,钻孔内岩石新鲜,劈理发育。孔深196m,橄榄岩厚度约110m,下部为花岗闪长片麻岩。橄榄岩主体呈块状构造,边缘呈条带状构造,靠近片麻岩的橄榄岩蛇纹石化强烈。除了10cm厚的岩脉原岩为岩浆分异的产物外,岩石主元素、微量和稀土元素地球化学显示,原岩为极亏损的地幔方辉橄榄岩。岩石主要矿物组成为橄榄石(85%~95%) 斜方辉石(3%~5%) 角闪石(3%~5%) 尖晶石(约0.5%) 镍硫化物(<0.1%),个别部位含有石榴石、单斜辉石和白云石。根据矿物的结构和成分,大体分为三个期次的组合。早期残余地幔矿物组合,由镁橄榄石、富铝顽火辉石、铬尖晶石和透辉石组成,具残余斑状结构,常含有包体,为高温低压组合;超高压变质期矿物组合,由镁橄榄石、镁铝榴石(Pyr=62~66)、低铝顽火辉石、铬尖晶石组成,具细粒变晶结构,无包体,变质温压为840~940°C、3.0~4.1GPa;麻粒岩相─角闪岩相变质期矿物组合,包括韭闪石、镁铝尖晶石、铬尖晶石、白云石、透闪石、蛇纹石,变质温度和压力为650~780℃、<1.8GPa。马草夼橄榄岩作为地幔楔,在印支期发生了超高压变质作用,并在折返过程中叠加了麻粒岩相-角闪岩相的变质作用。     

湘南晚中生代玄武岩中发现下地壳包体

湖南南部中新生代玄式岩分布于宁远、道县、新田一带,既有喷溢相的熔岩、火山碎屑岩,又有次火山相的岩管及岩脉。根据岩相学观察,有碱性橄榄玄武岩、橄榄玄式岩,亦有超基性的白榴辉橄岩。其中除含有尖晶石二辉橄榄岩、尖晶石方辉橄榄岩等上地幔包体外,最近我们在野外考察中还发现有下地壳的包体,主要岩石类型是石榴石黑云母二长片麻岩、石榴石黑云母石英片岩、石英岩质糜棱岩、橄榄长石岩(己变为赤铁矿、伊丁石、皂石化长石岩)、蛇纹岩、珪化蛇纹岩等。其中前三和岩石黑云母为含Ti较高的棕红色黑云母,石榴石为浅粉色镁铝榴石,由矿物特征推测变质程度至少达高角闪岩相。这在本区的包体研究中属首次报道。     

西藏普兰地幔橄榄岩中尖晶石内的钙长石包裹体及其成因

西藏普兰超镁铁岩体之东南缘与玄武岩接触界线附近的地幔橄榄岩中除有粒状半自形的钙长石产出外,还在尖晶石中发现有呈蠕虫状、浑圆状的钙长石包裹体存在.研究发现两种产状的钙长石An值都大于95且均无环带构造,说明钙长石从高Ca/Al比值的熔体中结晶时具有结晶时间短、结晶速度快的特点,可能形成于地壳较浅部位.从化学成分来看,包裹体形态的钙长石具有较高的Cr2O3含量,其寄主矿物尖晶石的Cr#值低且TiO2含量比深海橄榄岩中的尖晶石低得多,推断钙长石包裹体与寄主矿物尖晶石是在液相条件下几乎同时结晶的产物.综合研究表明钙长石包裹体的成因可能是玄武岩熔体在地壳较浅部位侵入方辉橄榄岩时,高温的玄武质熔体提供热源,使得方辉橄榄岩中尖晶石内的Cpx+ Opx细粒矿物包裹体在高温环境下发生熔融,发生Opx+ Cpx+ Sp→Ol+ Pl的反应,由于这种情况下尖晶石有剩余,故新生成的橄榄石和钙长石矿物仍然包裹于尖晶石内,从而形成尖晶石内部呈蠕虫状的钙长石包裹体.     

东濮凹陷北部沙河街组三段中亚段沉积环境分析

东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。     

The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads

In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.     

郯庐断裂南段研究进展与断裂性质讨论

据1：5万区域地质调查和专题研究资料，就郯庐断裂带是否南延与消失的原因，其与大别—苏鲁造山带交截形成的假位错效应，以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上，讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。     

塘口水电站坝基岩体透水性和渗漏问题分析

塘口水电站大坝基础座落在断层和裂隙较发育的龟裂纹灰岩上,岩体完整性差、透水性强,多年运行后,大坝灌浆廊道和排水廊道出现多处集中性漏水,为确保大坝安全和电站正常发电,根据渗漏性质和成因,采用对灌浆廊道补充帷幕灌浆,对排水廊道进行固结+帷幕+回填灌浆。通过灌浆处理后,效果良好,表明灌浆工程有效的将导致坝基渗漏的上下游的裂隙通道封闭,并顺利的经受了随后的汛期洪水考验,大坝安全得到保障。     

Unity of the national and the international in the socio-cultural development of the peoples of the USSR

International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.     

某高速公路下伏煤矿采空区稳定性分析

在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。      

Calculation of the Inverse of the Covariance

In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix.     

Report of the restudy of the defined global stratotype of the base of the Silurian System

The Global Stratotype Section and Point （GSSP） for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy （SSS） proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy （ICS）. The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob＇s Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.     

Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth

It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T ₃ = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.     

Artemia in the Salt Lakes of Russia:the Productivity of Populations,the Reserves of the Cysts and the Fisheries

正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the