渤海湾盆地歧口凹陷沙河街组一段下亚段湖相白云岩及其与海相白云岩的差异

渤海湾盆地歧口凹陷古近系沙河街组一段下亚段湖相白云岩主要为颗粒白云岩和泥晶白云岩两大类,常与泥质岩成薄互层或与其他碳酸盐岩互层产出。该湖相白云岩有序度较低,类似于海相准同生白云岩;Mg/Ca值偏离正常的化学计量值,具有富钙特征,说明其为快速交代的产物;碳氧同位素、Z值分析结果则反映了湖水的咸化程度较高。根据低海平面期蒸发浓缩盐水在湖底形成密度层并向灰质沉积层中回流渗透导致白云石化发生的机理,建立了歧口凹陷沙一下亚段湖相白云岩的成因模式。湖相白云岩的分布特征及其与海相白云岩的差异分析表明,湖相白云岩具有分布面积小、白云石化作用不彻底等特征,油气储集性能较为局限。     

白云岩化作用类型及机理——以歧口凹陷古近系沙河街组一段为例

通过镜下鉴定和地球化学分析对歧口凹陷古近系沙一段白云岩进行了研究,综合分析了研究区发育的岩石类型及其成因。结果表明:研究区发育泥-微晶白云岩、灰质白云岩、白云质灰岩及少量颗粒白云岩;Sr/Ba值为0.44.9,V/Ni值为1.37.1,Z值(盐度指数)分布在122.6162.5;87Sr/86Sr值和同期海水极为接近,因此推断湖盆遭受了海侵作用,海侵为白云岩化作用提供了Mg~(2+);有序度分布在0.22 0.53,整体较低;Mg/Ca值为0.730.91,反映了富钙低镁的特征,表明白云岩形成于准同生阶段。碳氧同位素分析表明,研究区白云岩形成于浅埋藏环境,并且受到了发酵作用的影响,异常高的Sr值也反映了微生物活动的存在。通过以上证据推断本区白云岩是在准同生期、浅埋藏环境、经渗透回流作用形成的,并且受到了发酵作用的影响。     

济阳坳陷沾化凹陷沙一下亚段优质烃源岩成因分析

沾化凹陷发育沙四上亚段、沙三下亚段和沙一下亚段3套烃源岩,前人对沙一下亚段烃源岩未进行深入研究。本文利用有机地球化学方法对沾化凹陷沙一下亚段烃源岩品质进行分析,研究表明沙一下亚段烃源岩有机质丰度高、干酪根类型以Ⅰ型为主,为优质烃源岩;烃源岩沉积中心位于渤南洼陷,但孤南洼陷烃源岩品质最好。孤北洼陷和孤南洼陷的部分烃源岩达到大量排烃阶段,所以勘探开发研究应重视来自沙一下亚段烃源岩的贡献。沉积环境分析表明,沙一下亚段沉积期沾化凹陷构造沉降速率较小,气候为北亚热带至暖温带中等偏干旱气候,均不支持形成优质烃源岩。沙一下亚段高品质烃源岩的形成的主要原因是高盐度导致湖泊的高生产力和良好的水体分层。湖盆高盐度是由于鲁佩期的海侵导致,海侵沿孤南洼陷—孤北洼陷—渤南洼陷的方向推进,导致孤南洼陷虽然不是沉积、沉降中心,但烃源岩品质最好。     

济阳坳陷沙河街组锶硫同位素特征

通过对研究区锶硫同位素特征分析,探讨济阳坳陷古近纪是否遭受过海侵作用.结果表明:沙四上亚段和沙三下亚段87Sr/86Sr值为0.707 6～0.709 9,属于同时期海相锶同位素范围;沙四上亚段δ34S为15‰～24‰,也属于同期海相硫同位素范围.结合前人研究成果,认为济阳坳陷沙四上亚段和沙三下亚段沉积时段曾不同程度受到海侵作用的影响.     

东营凹陷古近系中深层湖盆演化中的无机元素响应

为查明无机元素分布与水深、盐度等沉积环境以及湖盆演化过程的关系,采用电感耦合等离子体发射光谱仪分析对东营凹陷郝科1科探井古近系深层微量元素含量进行了测试、分析,所涉及的研究层位是该凹陷的主要烃源岩层段（沙河街组三亚段、沙河街组四亚段、孔店组）,分析结果表明:在水体浅、蒸发作用强烈的孔店组—沙四下亚段强氧化性滨浅湖环境里,钙、锶含量和Ca/Mg、Sr/Ba、Sr/Ca参数值具低值响应,铁、铝、钡、钒含量和（Fe+Al）/(Ca+Mg)参数值具高值响应;在沙四中亚段膏岩、盐岩等普遍发育的盐湖环境中,钠、锶含量和Sr/Ba、Fe/Mn、Sr/Ca均出现高值响应,锰、钡、钒含量和V/Ni、(Fe+Al)/(Ca+Mg)出现低值响应;在还原性的沙四上亚段半咸化深湖环境中,钾、钠、铁含量和Fe/Mn值具低值响应,钙、锰含量具高值响应;在沙四中亚段膏盐与泥岩共生体系中元素分布离散性明显,呈现波动性特征;Sr/Ba、Sr/Ca在盐湖环境中出现显著的高值响应,被证实可以作为良好的水体盐度指标参数,Fe/Mn、(Fe+Al)/(Ca+Mg)随水体加深逐渐增大,是良好的水体深浅指标参数。元素分布受沉积环境、岩性特征等多种地质因素的影响,在利用元素含量分布及特征元素比值来判断某单个地质因素的变化时,应该应用多种参数,进行综合判断。     

渤海湾盆地饶阳凹陷沙一下亚段古湖泊环境与烃源岩发育模式

学者们对饶阳凹陷烃源岩的研究已经取得了一些成果,但针对沙一下亚段烃源岩发育时期的古湖泊环境却缺乏系统的研究,忽略了湖泊环境这个控制烃源岩地球化学特征和时空展布的重要因素.通过对沙一下亚段烃源岩样品的古生物资料、有机地球化学、微量元素和同位素分析,恢复其古气候、湖泊古水深、古盐度、氧化还原条件和古生产力,综合这些影响因素建立了沙一下亚段优质烃源岩的发育模式.结果表明,沙一段下亚段（Es₁下）的优质烃源岩多发育于湖侵体系域沉积期,气候正从干旱炎热向温暖潮湿转变,湖水深度约为2~14 m,浪基面深度为7.5 m;古盐度参数如Sr/Ba和B/Ga等都指示了沙一下亚段湖侵体系域沉积期属于咸水环境,形成了稳定的盐度分层,从而造成底层水处于稳定的缺氧条件,有利于有机质的保存;而稳定碳同位素和营养元素的分布特征都表明此阶段湖泊表层水体有较高的初始生产力.这样的古湖泊环境造成强还原咸水半深湖沉积的有机相分布较广,有利于优质烃源岩的发育.      

塔里木盆地下奥陶统白云岩化流体来源的地球化学分析

塔里木盆地是中国重要的含油气盆地,其中奥陶系白云岩是主要储层之一,然而有关白云岩成因的问题众说纷纭,其中的关键是对于白云岩化流体性质的认识不一。元素地球化学和同位素测试分析表明,白云岩的稀土元素来源大部分继承原始灰岩,具有与海水类似的配分特征,只不过稀土元素的含量明显增高了;Sr、Ti含量和Sr/Ba比值较高,且Sr和Mn都具典型的埋藏演化特征;碳、氧同位素分布于正常海相范围内,与典型的埋藏白云岩特征类似;在局部发育一些与断裂相关的铁(锰)白云岩和鞍状白云岩,显示明显的Eu正异常,具相对较高的Fe-Mn-Ba-Si(-Zn-Pb)元素含量及Sr/Ba比值。分析结果说明塔中和塔北下奥陶统的白云岩化流体主要为正常或浓缩了的海水,白云岩形成于准同生和/或埋藏环境,局部发育与断裂相关的热液白云岩,而前人强调的大气淡水或混合水作用对白云岩的形成并不重要。     

歧口凹陷滨海地区沙一下鲕粒发育特征与重力流沉积

沙一下沉积时期,歧口凹陷板桥斜坡、滨海斜坡和歧北低斜坡滨海地区主要沉积类型为重力流沉积,物源主要来自西部沧县隆起。同时在滨海地区CT16×1等井沙一下部分取样薄片中发现鲕粒的存在。通过对歧口凹陷300余口井沙一下亚段薄片等资料的统计分析,认为滨海地区沙一下层段中的鲕粒为异地鲕粒,其来源主要为板桥斜坡及滨海斜坡,以上地区在沙一下沉积时期虽然仍以陆源碎屑沉积为主,但在某些短时段内,存在＂暖、清、浅＂的区域性欠补偿的高钙清水沉积,发育含鲕粒的碳酸盐岩,形成的原地鲕粒在后期重力流滑塌等事件活动的作用下,沿着滨海、港东断层等输送通道被搬运至滨海地区。通过此次鲕粒来源分析,一方面重新梳理了歧口凹陷两大盆外物源（北部燕山、西部沧县隆起）的波及范围,深化了对歧口凹陷沙一下沉积时期沉积体系的认识;另一方面发展形成了利用地震相、测井相、岩芯相和薄片相＂四相合一＂的沉积体系研究方法。     

江汉盐湖盆地盐间白云岩特征及成因分析

江汉盐湖盆地潜江凹陷古近系潜江组广泛沉积了一套盐间非砂岩,本文详细研究了该套盐间非砂岩中白云岩的分布、类型、矿物学特征及地球化学特征,探讨了盐间白云岩的成因。研究表明,该套白云岩主要为泥晶白云岩。发育程度与盐岩量成正比。盐间白云岩的矿物组分复杂,白云石有序度低,微量元素以富Fe、Na、高Fe/Mn比值为特征。盐间白云岩主要为盐湖湖盆沉积环境的产物,水体盐度高,总体为碱性环境,Mg/Ca比值低,主要为原生-准同生阶段沉积的产物。     

冀中坳陷饶阳凹陷蠡县斜坡古近系沙河街组一段浅水三角洲和滩坝的沉积环境

浅水三角洲和滩坝不仅是当今沉积学研究热点,也是油气勘探重要的沉积类型,沉积环境控制着浅水三角洲和滩坝沉积体系的发育及演化。基于岩心、钻井、测井数据及孢粉化石、微量元素等分析化验资料,对渤海湾盆地冀中坳陷饶阳凹陷蠡县斜坡古近系沙河街组一段(简称"沙一段")的沉积体系类型及沉积环境进行了综合研究。研究表明:(1)沙一段主要发育浅水三角洲和滩坝沉积。其中,沙一下亚段尾砂岩沉积时,以浅水三角洲内前缘、外前缘沉积为主;沙一下亚段特殊岩性段沉积时,湖平面上升,浅水三角洲退积,以滨浅湖滩坝为主;沙一上亚段沉积时,湖平面下降,三角洲向湖盆中心持续推进,沉积主体转变为浅水三角洲。(2)浅水三角洲和滩坝的沉积演化受控于沉积环境。沙一下亚段尾砂岩沉积时,处于较为干旱的亚热带气候,沉积水体较浅,为微咸水—半咸水的氧化环境,有利于浅水三角洲的发育;沙一下亚段特殊岩性段沉积时,发生大规模湖侵,水体加深,物源供给少,气候相对湿润,且盐度增加,过渡为还原环境,有利于滨浅湖滩坝的形成;沙一上亚段沉积时,物源供给充足,整体处于相对湿润的温带、亚热带气候,湖盆收缩,水体变浅,盐度相对较低,处于氧化条件下的淡水环境,有利于浅水三角洲的沉积。     

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。     

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。      

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。     

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.     

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.     

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