四川盆地西部中二叠统栖霞组晶洞充填物特征与热液活动记录

热液环境在碳酸盐岩成岩作用中十分重要,MVT铅锌矿床和热液白云岩储层都与之有关。四川盆地西部中二叠统栖霞组普遍发育厘米级大小的晶洞,其充填物主要为晶体粗大的非平直晶面鞍形白云石,这些鞍形白云石经历了广泛的溶解作用,次生方解石充填于鞍形白云石溶解空间及其晶间孔隙中。本文在碳酸盐岩岩石学特征研究的基础上,测试了晶洞充填物的碳氧同位素组成、元素构成和包裹体均一化温度,结合川西中二叠统埋藏历史和二叠纪以来的非地热增温热事件,研究了晶洞充填物中鞍形白云石的沉淀与溶解流体,以及充填于鞍形白云石溶解空间和晶间孔隙中次生方解石的沉淀流体。研究表明:在作为晶洞充填物的碳酸盐矿物中,鞍形白云石和沉淀于白云石晶间、晶内的次生方解石具有显著不同的氧同位素组成和包裹体均一化温度,前者δ18O值-5.94‰～-4.35‰,包裹体均一化温度主要为110～210℃,后者δ18O值-10.34‰～-8.75‰,包裹体均一化温度主要为70～110℃,据此反演的鞍形白云石沉淀流体的δ18O值为+4‰～+14‰(SMOW),方解石相应值为-4‰～+5‰(SMOW),显示白云石是在高盐度和高温流体中沉淀的,方解石是在相对低盐度和低温流体中沉淀的;晶洞充填物的碳同位素分析表明,鞍形白云石和沉淀于白云石晶间和晶内的次生方解石的δ13C值大致分布在0.7‰～2.6‰的范围内,显著低于同期海水的δ13C值,两种碳酸盐矿物中的碳具有同期海水和深部CO2混合碳源的特征;中二叠世末东吴运动期间峨眉山玄武岩喷发时岩浆活动的热效应导致了当时处于浅埋藏环境的栖霞组地层中鞍形白云石的沉淀,而热事件后流体温度和盐度的同时降低则使得鞍形白云石溶解,同时伴随方解石沉淀在鞍形白云石溶解后的孔隙和晶间孔隙中。     

塔里木盆地塔北、塔中地区寒武系—奥陶系碳酸盐岩中鞍形白云石胶结物特征

通过对塔里木盆地中、北部地区寒武系—奥陶系碳酸盐岩的研究,发现鞍形白云石胶结物发育比较普遍,常见于孔洞或裂缝之中,乳白色,晶体粗大,晶面弯曲或呈阶梯状,镜下波状消光,晶体内部常见微裂缝,常与热液矿物共生。本文对28个鞍形白云石样品进行了碳、氧、锶同位素测试,结果显示鞍形白云石的δ~(13)C和δ~(18)O值分别介于-2.446‰～0.686‰和-9.101‰～-5.117‰之间,~(87)Sr/~(86)Sr值介于0.708 6～0.710 2之间;流体包裹体测温分析表明,鞍形白云石中气—液两相包裹体的均一温度(T_h)介于121～159.5℃之间,但集中分布在135～145℃之间;根据最后冰融点温度(T_m)求得的白云岩化流体盐度介于21.3%～23.1%之间。这些数据表明,该类型白云石形成于热卤水(盐度是海水的5～8倍)之中。塔里木盆地鞍形白云石与世界范围内其它盆地的鞍形白云石的碳、氧同位素特征基本相似,但其~(87)Sr/~(86)Sr值相对偏低。导致这一现象的原因可能是鞍形白云石形成于来自深部的岩浆热液流体之中,这些流体伴随岩浆侵位或通过切穿基底的深大断裂及其与之相连的次级断裂系统从深部直接进入碳酸盐岩地层中,未经过碎屑岩输导层的长时间运移,所以导致其中形成的鞍形白云石~(87)Sr/~(86)Sr值偏低。     

黔东南石英脉型金矿床中铁白云石流体包裹体研究

铁白云石是黔东南石英脉型金矿主成矿阶段的主要脉石矿物之一,与金的矿化关系十分密切,在金的运移、沉淀等方面起着重要作用,其流体包裹体特征可以反映成矿流体性质。通过对铁白云石开展系统的流体包裹体岩相学观察、均一法测温和冰点测定,计算出包裹体盐度和密度等数据。结果表明: 铁白云石包裹体较为发育,以含CO₂的包裹体为主; 均一温度集中在240~300 ℃范围内,平均均一温度为267.21 ℃; 成矿流体的盐度为7.31%~21.40%(NaCl),平均为15.31%(NaCl); 成矿流体的密度介于0.72~0.97 g/cm³之间,平均为0.89 g/cm³。认为黔东南石英脉型金矿床属于低盐度、高密度的中温热液矿床。     

四川盆地东南地区林1井灯影组鞍形白云石成因及其意义

对四川盆地东南地区林1井上震旦统灯影组鞍形白云石的岩相学特征和碳、氧、锶同位素特征及流体包裹体成分与温度进行研究,认为它属热液成因。研究区热液活动在岩相学上表现为充填状鞍形白云石,发育鞍形白云石线状充填晶洞。鞍形白云石共生矿物包括石英、沥青等。鞍形白云石δ18O值和δ13C值异常偏负,87Sr/86Sr值异常偏高,与围岩差异明显。鞍形白云石原生流体包裹体均一温度为270～320℃,明显超过了该井最高埋藏温度;流体包裹体的气相部分以CO2、CH4和N2为主,液相部分以H2O和CO2为主。这些特征表明,形成鞍形白云石的流体来自于基底的热液,灯影组白云岩受热液溶蚀改造而发育热液改造型白云岩储层,并有过油气成藏过程。     

南羌塘坳陷扎仁地区中侏罗统布曲组晶粒白云岩成因分析

以青藏高原南羌塘坳陷扎仁地区中侏罗统布曲组晶粒白云岩为对象对其进行成因的研究。通过显微镜观察、流体包裹体数据以及碳氧同位素分析,认为研究区白云岩可分为细粉晶白云岩、中晶白云岩以及粗晶白云岩,在裂隙附近还广泛发育晶粒较粗大的鞍形白云石。白云石中流体包裹体均一温度在150.2～216.0℃,盐度均值达到了24.5%NaCl,远高于方解石包裹体均一温度与盐度,表明白云石的形成经历了高温高盐度的过程。白云石碳氧同位素分析显示其δ~(13)C_(PDB)值为-0.01‰～3.43‰,δ~(18)O_(PDB)值为-11.17‰～-7.68‰,通过白云石-水氧同位素分馏方程得到白云化流体的δ~(18)O_(SMOW)值为4.82‰～12.85‰,δ~(13)C_(PDB)对比认为白云石受寄主灰岩环境的影响。通过碳氧同位素数据对比以及前人的研究结果,认为研究区白云岩为相对封闭环境下受岩浆活动加热的高盐度流体对寄主灰岩交代的产物,高盐度流体由于镁离子的消耗导致流体对方解石过饱和,继而沉淀了高温的方解石。因此,热液活动对研究区中侏罗统布曲组白云岩的发育具有重要意义,值得加强对这一方向的探索研究。     

下庄铀矿田流体包裹体地球化学研究

对下庄铀矿田不同矿体矿石中的石英、萤石、方解石等脉石矿物进行了系统的流体包裹体测温工作。研究结果表明,下庄铀矿田从成矿早期→成矿期→成矿晚期均一温度明显降低,但流体盐度变化不大,均为低盐度的流体。下庄铀矿田不同矿床均一温度与流体盐度具有相似的变化范围,矿床在中温(187~275℃)与低盐度(NaCl1.6~9.6wt%)条件下形成。     

湖南瑶岗仙石英脉型黑钨矿床成矿流体特征

利用红外显微镜对湖南瑶岗仙石英脉型黑钨矿床中不透明矿物黑钨矿的流体包裹体以及黑钨矿共生的透明矿物石英中的流体包裹体进行显微测温对比分析,结果表明,黑钨矿中的原生流体包裹体有富液体包裹体、纯液体包裹体和富气体包裹体等,其均一温度范围大致在230℃~320℃,平均温度为281℃;冰点-4.2℃~-12.9℃,盐度6.74%~16.80%溶液。石英中流体包裹体主要为富液体包裹体,其均一温度范围大致在202℃~273℃,平均温度为240℃;冰点-0.5℃~-4.1℃,盐度为0.88%~6.59%溶液。黑钨矿形成时捕获的流体属于中温、中等盐度、低密度的流体,石英形成时捕获的流体属于中低温、低盐度、低密度的流体。通过黑钨矿中流体包裹体的显微测温结果及前人研究成果分析显示,成矿流体主要来自岩浆,流体演化经历了自然冷却、混合作用等过程,这些过程可能是钨沉淀的有效机制。     

云南会泽矿山厂铅锌矿床流体包裹体特征及成矿物理化学条件

通过会泽矿山厂铅锌矿床闪锌矿流体包裹体显微测温和成矿物理化学条件参数计算,结合前人研究结果,得出以下认识:会泽矿山厂铅锌矿床闪锌矿流体包裹体均一温度为126280℃,具有较宽的变化区间,盐度(w(NaCl))为3.2%22.8%;白云石流体包裹体均一温度为86163℃,大部分盐度较低,为1.1%-14.8%。3个成矿阶段闪锌矿和白云石中流体包裹体均一温度和盐度具有较明显的分布特征:从热液成矿期Ⅰ阶段→Ⅱ阶段→Ⅲ阶段→围岩蚀变,流体呈现中高温-高盐度→中温-中高盐度→中低温-中高盐度→中低温-低盐度的演化规律。在整个热液成矿过程中,有两种不同盐度的流体参与了作用,流体混合可能是矿物沉淀的主要机制。pH值计算结果表明,迁移阶段时,成矿流体呈酸性,从成矿阶段Ⅰ—Ⅳ,流体pH逐渐增大,主成矿阶段Ⅱ—Ⅲ时,闪锌矿和方铅矿在中性、弱碱性下大量析出。受控于CO、CO_2、O_2间逸度平衡的CO_3~(2-)和HCO_3~-缓冲对调节了成矿流体的pH值,碳酸盐岩在铅锌的运移沉淀中起了至关重要的作用。     

松辽盆地南部红岗油田青山口组砂岩中片钠铝石的形成温度

主要以松辽盆地南部红岗油田富含片钠铝石砂岩的红143和红146井为研究对象,通过普通薄片鉴定、茜素红-S染色、扫描电镜、能谱分析、显微测温等分析方法,对研究区含片钠铝石砂岩的成岩共生序列,尤其是流体包裹体均一温度进行了详细的研究.红岗油田成岩共生序列为:黏土矿物→石英次生加大边→方解石→片钠铝石→铁白云石→石英愈合微裂...     

大兴安岭南段白音诺尔铅锌矿床流体包裹体研究

白音诺尔铅锌矿床是我国长江以北最大的铅锌矿床,矿区出露二叠纪地层和中生代岩浆岩。流体作用过程可大致分为3个阶段,即前成矿阶段(P阶段)、同成矿阶段(S阶段)以及后成矿阶段(L阶段)。P阶段以发育钙质石榴石、辉石等典型的矽卡岩矿物为主,辉石中普遍发育含石盐子晶包裹体(~44% NaCleqv)和富气相包裹体的共生组合,且具有相同的均一温度(~470℃),显示了流体不混溶作用的发生。该阶段流体捕获压力~400bars,对应形成深度~1.5km。这一阶段还发育以石盐子晶消失而达到均一的高盐度流体包裹体,其均一温度为~390℃,盐度为~46% NaCleqv,估计的最小压力分布范围较大(150~3000bars,平均~1200bars)。S阶段发育含水矽卡岩矿物(如绿帘石),并伴随闪锌矿等大量硫化物的沉淀。闪锌矿以及与之共生的石英、方解石中均发育富气相和富液相包裹体的共生组合,显示了流体沸腾特征。其中富液相包裹体盐度为6.6±3.0% NaCleqv,与其共生的富气相包裹体盐度为1.3±0.6% NaCleqv,二者均一温度皆在350℃左右,平均捕获压力为~150bars,以静水压力估计深度也为1.5km。L阶段矿化已经基本结束,发育大量的方解石(-石英-萤石)脉体。这一阶段发育特征的CaCl₂-NaCl-H₂O体系流体,均一温度<250℃,且随着均一温度降低,流体中Ca/Na比值有上升的趋势。流体包裹体研究显示了白音诺尔铅锌矿的成矿流体来自于深部岩浆,跟围岩地层无关。早期流体不混溶作用是矽卡岩矿物结晶的主要机制,随后的流体沸腾作用与大规模成矿作用密切相关。两期流体来自深部岩浆房不同时期的出溶,并经历了不同的温压演化过程。     

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.     

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.     

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。      

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