黔东北石阡志留纪最早期生物礁的形态学和古生态学

上扬子区志留纪早期的浅水相灰岩和壳相动物分布,多局限于滇黔桂古陆之北陆浅海近岸带。黔东北石阡兰多维列世埃隆期香树园组上部记录了华南板块奥陶纪末生物灭绝事件之后最早后生动物礁群落的复苏,持续相对长时间清澈浅水环境是造礁的基本条件,南陆北海的古地貌塑造了礁体各亚相的展布方式,礁灰岩南北延伸出露宽度约为150m,最大保存厚度约为20余米,形态学上呈现点礁特征。棘屑滩之上的珊瑚—层孔虫格架礁具有较高的生物多样性,属全球志留纪最常见的礁灰岩类型;南侧为礁后薄层棘屑滩堆积;礁核部位的大量珊瑚—层孔虫原地生长格架具有抗浪性,并障积不同粒度的壳相化石和内碎屑颗粒,有利于加速沉积形成块状礁灰岩和正向地貌;礁体北端为薄层生屑灰岩夹少量粉砂—泥质薄层的礁前沉积区;礁顶薄层灰岩中粉砂质—泥质成分逐渐取代珊瑚—层孔虫格架岩,相变为雷家屯组下部的陆源碎屑岩沉积,海水浑浊度增高是终止生物礁群落栖居的主控因素。     

重庆开县上二叠统长兴组红花生物礁成礁模式

通过对红花生物礁露头的精细解剖和微相分析,研究了礁的内部构成和成礁模式。红花生物礁发育3期礁体旋回：礁A、礁B和礁C。礁A由生屑泥晶灰岩和骨架岩构成;礁B由生屑泥晶灰岩、粘结岩、骨架岩和生屑灰岩构成;礁C由粘结岩、骨架岩和生屑灰岩构成。红花生物礁造礁生物有钙质海绵、钙藻类、苔藓虫和水螅类,附礁生物为有孔虫、腕足类、双壳类、腹足类和棘皮动物等。单个礁体内,由下往上的生物演化为：腕足类+双壳类+有孔虫组合→钙藻类→钙质海绵+水螅类+钙藻类+苔藓虫组合→生物碎屑;岩性演化为：生屑泥晶灰岩→粘结岩→骨架岩→生屑灰岩。礁B的生屑滩内生屑间为泥晶充填,生屑分选、磨圆较好,是由相邻的高能生屑滩侵蚀搬运到礁B侧翼低能区沉积形成。3期礁都发育在碎屑滩上,礁A为低能环境下形成的礁,礁B和礁C在礁A形成的高地上成礁,为高能环境礁;单个礁体的完整成礁模式为：在浅滩之上,钙藻类大量生长、粘结吸附颗粒固结基底,钙质海绵和钙藻类在硬质基底上繁茂生长,形成具有抗浪格架的生物礁,礁体暴露水面死亡后遭波浪、水流改造形成生屑滩。     

黔北桐梓狮溪志留纪埃隆晚期石牛栏段的生物滩相

志留纪兰多维列世埃隆晚期,滇黔桂古陆以北的陆表海缓坡上沉积了石牛栏组石牛栏段浅水灰岩。珊瑚—层孔虫为主的后生动物格架岩建造的点礁分布北界仅延伸到桐梓水坝塘一带;更远岸的狮溪镇白芷垭剖面虽然远离古陆剥蚀区,层状灰岩中极低的粉砂质、泥质含量指示高清澈度的环境指标,内碎屑和少量生屑混合沉积的滩相灰岩沉积深度在最大浪基面之上,但珊瑚—层孔虫密度偏低,后生动物格架岩的丰度以及个体大小均达不到礁灰岩的标准,也不呈现生物礁特有的正向海底地貌。本文实例诠释了海底深度变化显著制约底栖群落的古生态分异,后生动物点礁栖居的深度范围有限。     

川东南—黔北地区志留纪生物礁与古环境演化

川东南－黔北地区下志留统分布广泛，出露好，化石丰富，在海相碎屑沉积中不同程度地发育了碳酸盐岩和和生物礁，我们通过对重庆綦江观音桥，贵州坡渡及邻区石牛栏组的野外考察和综合研究发现，生物礁主要发育在早志留世中晚期的石牛栏组中，下部，类型为小型点礁，生物丘及生物层。造礁生物以床板珊瑚，皱纹珊瑚，层孔虫为主；附礁生物包括苔藓虫，腕足类，鹦鹉螺，海百合等，礁基为生屑滩或瘤状灰岩。     

西藏安多县东巧晚侏罗世生物礁的发现

首次发现西藏安多县东巧地区晚侏罗世生物礁,造礁生物以层孔虫和六射珊瑚为主,其中,层孔虫可分为枝状、筒状和块状三种类型,它们多以原地生长状态保存.礁岩石学特征研究表明,礁岩可分为筒状-枝状层孔虫障积岩、枝状层孔虫障积岩、筒状层孔虫障积岩、筒状-块状层孔虫障积-骨架岩和筒状层孔虫-六射珊瑚障积-骨架岩.礁体类型可分为筒状-枝状层孔虫障积岩隆礁、枝状层孔虫障积岩隆礁、筒状层孔虫障积岩隆礁、筒状-块状层孔虫障积-骨架岩隆礁和筒状层孔虫-六射珊瑚障积-骨架岩隆礁,礁体的演化均经历了奠基阶段、发育阶段和衰亡阶段.     

西沙海域新生代生物礁序列的沉积构成:以西科1井为例

生物礁是由原地的固着生物所建造的块状碳酸盐岩沉积。西沙海域自中新世以来发育了厚层生物礁地层。通过对最新全取心钻井西科1井岩心的宏观观察和微观分析,结合古生物及岩心测试成果,发现西科1井中新世和第四纪为主要造礁期,形成了两套分别以珊瑚藻和珊瑚为主要造礁生物的生物礁序列,底栖有孔虫为主要的附礁生物,而上新统为一套滩相沉积。生物礁序列发育骨架岩、粘结岩和障积岩三种礁相岩石,以骨架岩含量最高,非礁相岩石包括泥灰岩、颗粒灰岩和生物碎屑灰岩三种。白云岩地层以晚中新世到上新世早期最为发育,多为准同生白云石化作用所致,并受热液活动的影响。对生物礁序列的沉积分析,可为后期南海油气勘探以及生物礁储层分布研究提供一些基础材料。     

塔中地区中上奥陶统台地镶边体系分析

塔里木盆地塔中地区中上奥陶统碳酸盐岩台地边缘以发育良好的多种粒屑滩和生物礁组成的镶边沉积体系为特征。通过精细的单井相分析,识别出砂屑滩、砾屑滩、生屑滩以及鲕粒滩等,并且区分出3种不同类型的生物礁：①隐藻灰泥丘;②主要由枝状苔藓虫、海绵或（和）珊瑚建造的障积礁;③由石质海绵、托盘类、层孔虫、珊瑚、管孔藻等建造的骨架礁。在面向深水盆地的台缘外带,以发育中～高能粒屑滩和骨架礁组合为特征。在背靠开阔海台地的台缘内带,主要表现为中低能粒屑滩、隐藻灰泥丘以及障积礁的组合。这个台缘镶边沉积体系总体上沿塔中1号断层西侧呈北西-南东向长带状展布,长度100多公里,是本区重要的油气聚集带之一。储层质量台缘外带总体上优于台缘内带,其中骨架礁礁核和粒屑滩灰岩最好,礁间海和滩间海沉积物较差。     

广西桂林晚泥盆世弗拉斯期珊瑚礁

桂林地区中、晚泥盆世从吉微特期到法门期都有不同的礁、滩发育，而且在不同时期造礁生物的面貌有所不同。晚泥盆世藻类的崛起取代了层孔虫和珊瑚的位置，成为造礁的主要角色。但在桂林以西５公里处的侯山，其沉积相位置为桂林台地的西北台缘，除发育藻－层孔虫礁外，还发育了层状的珊瑚礁体，这在晚泥盆世地层中还极为少见。这种礁体由原地生长的丛状珊瑚体构成，以Ｓｍｉｔｈｉｐｈｙｌｌｕｍｇｕｉｌｉ－ｎｅｎｓｅ为主，其生长高度可达一米多，分异度低，其它的造礁生物主要是一些藻类和少量层孔虫，附礁生物以腕足类为主。纵向上礁序列由以下几种微相组成:（１）隐藻泥晶灰岩；（２）藻砂屑灰岩；（３）斑马构造隐藻泥晶灰岩；（４）珊瑚灰岩。横向上礁组合可识别出:（１）礁后亚相；（２）礁坪和礁缘亚相；（３）礁坡亚相。从礁体的生物组成，微相内容特征，成岩变化及横向上与周边环境的关系可以推测，其并非真正的台缘礁体，而是礁后外带靠近台缘的层状补丁礁。     

广西田林龙江垌上石炭统黄龙组珊瑚礁古生态

广西田林县龙江垌见晚石炭世的珊瑚格架礁,分三层旋回式生长于海百合碎屑滩上。造礁生物为丛状群体珊瑚Diphyphyllum sp.,附礁生物主要是海百合、腕足动物、藻类和有孔虫。造礁生物种群间仅是共同栖息生存,缺乏长期、稳定、复杂的生态关系,礁体生物群落成熟度低,除Diphyphyllum sp.搭建格架外,缺少其他造礁方式,在当时多变的水动力条件下,只形成了未成熟的层礁。对于龙江垌珊瑚礁生态特征形成原因归纳为以下几点:石炭纪中期全球地质构造变化影响、微生物群团和藻类造礁作用不明显、海百合的强大竞争作用使底栖生物群落受到抑制、Diphyphyllum sp.生态特点使其造礁能力差。     

四川盆地东部中二叠统茅口组台内藻礁沉积特征

四川盆地东部月005-H1井发现了中二叠统茅口组三段中发育的小型台内藻礁。岩心分析表明,该生物礁以藻格架灰岩为主,造礁生物以叶状藻为主、见少量苔藓虫,含虫筳类、非虫筳有孔虫、腕足类、双壳类、海百合、棘皮类等附礁生物,藻片之间沉积有灰泥和少量生物碎屑。礁体纵向上发育两个较为完整的旋回,每个旋回发育四个成礁阶段,单个旋回厚度约1.5 m,每个旋回发育四个礁阶段,并可划分出礁基、礁核、礁盖(基)等亚相类型。认为该生物礁的形成与峨眉地裂运动引起的基底正断活动有关,形成于"堑—垒"构造格局的浅水型碳酸盐岩断隆之上。推测该类藻礁灰岩可能与茅口组古风化壳岩溶型储层关系密切。     

摩擦桩基桩土间极限摩阻力取值问题探讨

通过对广珠东线高速公路横沥大桥的试桩及土体的工程地质条件分析,总结出影响摩擦桩基桩土间极限摩阻力取值的一般问题以及解决问题的方法和措施。     

从榴辉岩与围岩的关系论苏鲁榴辉岩的形成与折返

位于华北和扬子两板块碰撞带中的苏鲁榴辉岩形成的温压条件不但是超高压，而且是高温。榴辉岩的PTt轨迹表明其为陆-陆磁撞俯冲带的产物。榴辉岩的区域性围岩花岗质片麻岩为新元古代同碰撞期花岗岩，榴辉岩及其他直接围岩皆呈包体存在于其中，并见新元古代花岗岩呈脉状侵入榴辉岩包体中。区域性围岩新元古代花岗岩的锆石中发现有柯石英、绿辉石等包裹体，表明新元古代花岗岩的组成物质也经受过超高压变质作用，且榴辉岩与围岩新元古代花岗岩的锆石U-Pb体系同位素年龄基本相同。但新元古代花岗岩所记录的变质作用和变形作用期次（或阶段）却少于榴辉岩。椐上述可得如下推断：超高压榴辉岩与新元古代花岗岩岩浆是同时在碰撞带底部（俯冲板块前部）形成的；榴辉岩的第一折返阶段是由新元古代花岗岩岩浆携带上升的，其第二折返阶段是和新元古代花岗岩一起由逆冲及区域性隆起而上升，遭受剥蚀。     

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.     

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。      

混凝剂处理钻井废泥浆液的研究

通过烧杯搅拌实验对混凝剂处理钻井废泥浆液进行研究,从混凝剂适应p H值范围、混凝效果、沉降速度三方面研究比较,找出一种较为理想的混凝剂,并分析了影响混凝剂性能的主要因素,确定了混凝剂的最佳投放剂量。      

黄河源区水环境变化及黄河出现冬季断流的原因

自1954年有水文观测资料以来，黄河曾在青海省玛多县黄河沿水文站发生过3次断流。本文在分析黄河源区水环境特征及其影响因素的基础上指出，鄂陵湖、扎陵湖的环湖融区调节能力低，当遇到连续干旱、冬季其调节水量不足以维系黄河径流时便会发生断流，这是断流的主因。湖水位降低、开采沙金、过度放牧等自然和人为因素也会对黄河发生断流产生影响。鄂陵湖口附近黄河上修建的水电站开始蓄水，提高了两湖及环湖融区的调节能力，今后黄河冬季出现断流的可能性将大为降低。     

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.     

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     

天山南坡科其喀尔冰川表碛区小气候特征研究

利用天山南坡科其喀尔冰川3号观测站2009年全年的气象观测资料,分析研究了科其喀尔冰川表碛区的小气候特征. 结果表明：总辐射和净辐射夏秋季较高、冬春季较低;反射辐射和地表反照率反之. 与其他地区不同,该区主要受积雪物理性质和下垫面状况的影响,冬春季地表反照率日变化表现为由大到小的变化过程,夏秋季表现为倒U型. 温度年变化表现为夏秋季高、冬春季低,最高月均值出现在8月,为9.4℃,最低月均值出现在1月,为-9.6℃. 受山谷风和冰川风的影响,全年的风向以西北风和西北偏西风为主,风向的日变化以11：00为界发生转向. 受降水和冰川消融等的影响,比湿夏秋季月均值较大,冬春季月均值较小.     

Climate: Is the past the key to the future?

 The climate of the Holocene is not well suited to be the baseline for the climate of the planet. It is an interglacial, a state typical of only 10% of the past few million years. It is a time of relative sea-level stability after a rapid 130-m rise from the lowstand during the last glacial maximum. Physical geologic processes are operating at unusual rates and much of the geochemical system is not in a steady state. During most of the Phanerozoic there have been no continental ice sheets on the earth, and the planet’s meridional temperature gradient has been much less than it is presently. Major factors influencing climate are insolation, greenhouse gases, paleogeography, and vegetation; the first two are discussed in this paper. Changes in the earth’s orbital parameters affect the amount of radiation received from the sun at different latitudes over the course of the year. During the last climate cycle, the waxing and waning of the northern hemisphere continental ice sheets closely followed the changes in summer insolation at the latitude of the northern hemisphere polar circle. The overall intensity of insolation in the northern hemisphere is governed by the precession of the earth’s axis of rotation, and the precession and ellipticity of the earth’s orbit. At the polar circle a meridional minimum of summer insolation becomes alternately more and less pronounced as the obliquity of the earth’s axis of rotation changes. Feedback processes amplify the insolation signal. Greenhouse gases (H₂O, CO₂, CH₄, CFCs) modulate the insolation-driven climate. The atmospheric content of CO₂ during the last glacial maximum was approximately 30% less than during the present interglacial. A variety of possible causes for this change have been postulated. The present burning of fossil fuels, deforestation, and cement manufacture since the beginning of the industrial revolution have added CO₂ to the atmosphere when its content due to glacial-interglacial variation was already at a maximum. Anthropogenic activity has increased the CO₂ content of the atmosphere to 130% of its previous Holocene level, probably higher than at any time during the past few million years. During the Late Cretaceous the atmospheric CO₂ content was probably about four times that of the present, the level to which it may rise at the end of the next century. The results of a Campanian (80 Ma) climate simulation suggest that the positive feedback between CO₂ and another important greenhouse gas, H₂O, raised the earth’s temperature to a level where latent heat transport became much more significant than it is presently, and operated efficiently at all latitudes. Atmospheric high- and low-pressure systems were as much the result of variations in the vapor content of the air as of temperature differences. In our present state of knowledge, future climate change is unpredictable because by adding CO₂ to the atmosphere we are forcing the climate toward a “greenhouse” mode when it is accustomed to moving between the glacial–interglacial “icehouse” states that reflect the waxing and waning of ice sheets. At the same time we are replacing freely transpiring C3 plants with water-conserving C4 plants, producing a global vegetation complex that has no past analog. The past climates of the earth cannot be used as a direct guide to what may occur in the future. To understand what may happen in the future we must learn about the first principles of physics and chemistry related to the earth’s system. The fundamental mechanisms of the climate system are best explored in simulations of the earth’s ancient extreme climates. Received: 7 November 1996/Accepted: 23 January 1997