The carbohydrates in relation to mineralogic and granulometric composition of surface sediments in the karst estuary (River Krka estuary,Yugoslavia)

The investigation of mineral, granulometric and chemical composition of sediments of the River Krka estuary (Yugoslavia) were performed in order to elucidate the origin of the sediments and the pattern of sedimentation. Estuarine surface sediments were found to be fine-grained with a bimodal distribution. Environmental conditions in estuarine sediments favour conservation of the organic matter (anoxic conditions). The carbohydrates in the sediments were investigated to determine whether they are of terrigenous or authigenous origin. Glucose, galactose, mannose, xylose, rhamnose, glucosamine and glucuronic acid were detected in the sediments. Their mutual relationship indicates a preferentially terrigenous source of sedimented organic material in estuarine sediments.     

广西河池地区矿产资源勘查成果展销会情况介绍

１９９５年７月１１日—１２日，广西地矿厅和河池地区行署首次联合举办矿产资源勘查成果展销会，会址设在河池市，与会代表１３０余人。展销会提交大会展销的矿产资源勘查成果３８项，引资勘查项目３８项。经买卖双方三天的洽谈，涉及到的项目２５项，会议期间签订矿产资源勘查成果合同协议４项，愈千万元，取得较好的社会经济效益。为地勘资金多渠道来源开辟了新路子，对促进地勘单位地质找矿工作及勘查成果有偿使用发挥了重要作用     

Optimization of grid-drilling using computer simulation

A computer simulation method has been developed to find efficient drilling grids for mineral deposits. A well-known ore deposit is used as a model to develop an efficient pattern for undiscovered ore bodies in the same area or in other prospects where similar geometry is suspected. The model for this study is the Austinville, Virginia deposit, a Mississippi Valley-type deposit composed of 17 ore bodies totaling 34 million short tons (30 million metric tons). The method employs a computer program that simulates drilling the model deposit with different patterns, including various levels of follow-up drilling. Follow-up holes are drilled in fences at one half the original spacing around holes in the grid that show ore-grade mineralization. Each pattern is drilled 100 times from random starting locations to provide a range of outcomes of drilling, including the best, worst, and most likely. For this study, patterns of 100 drill holes were composed of 10 fences spaced 1000–5000 feet (305–1524 m) apart, each with 10 holes spaced 200–1000 feet (61–305 m) apart. In all, 25 grids were used with zero to three levels of follow-up drilling. The 600/2000 grid, with drill holes spaced 600 feet (183 m) apart in fences spaced 2000 feet (610 m) apart, was compared with the 200/5000 grid because they represented contrasting outcomes. The 600/2000 grid penetrated many ore bodies consistently but with few multiple hits to individual ore bodies; whereas the 200/5000 grid inconsistently penetrated few ore bodies with many multiple hits. The 600/2000 grid was more efficient than the 200/5000 grid at hitting large ore bodies of 1,000,000 short tons or greater (900,000 metric tons or greater) and was made more effective by adding one cycle of follow-up drilling. The 600/2000 grid had a 97% chance of hitting one or more large ore bodies with at least one drill hole per ore body, and the 200/5000 grid had a 64% chance. Once hit, there was an 82% chance that the largest ore body would be penetrated by three or more holes when using the 600/2000 grid and an 88% chance using the 200/5000 grid.     

今后几年的月球探测和月球科学

近年来月球探测已经进入了一个全新的时代。特别是 1 990年以来 ,多个月球探测计划已经被成功实现 ,而且另外还有多个探测计划也在准备当中 ,并将在未来的几年内发射升空。在这种背景之下 ,中国的航天机构和有关的科学家也开始积极酝酿和开发自己的月球探测计划。这些月球探测计划将利用卫星上搭载的各种仪器探测和测量月球的地质和地理特性、化学成分和矿物组成、月球物理学特征以及包含地球大气在内的地月空间环境和行星际空间环境 ;进一步研究月球的起源和演化 ,探明月面环境 ,研究太阳等离子体物理 ,提供月面天文台和月面长期科研基地的候选地址 ,调查月球上的可利用资源 ,为将来开发月球提供充实的背景资料。参与新一轮的月球探测同样也为中国天文学研究带来了新的机会。     

A THREE-DIMENSIONAL ELASTIC NESTED-GRID MESO-(β-γ)SCALE ATMOSPHERIC MODEL——PARTI:MODEL DESCRIPTION

A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of fullequations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-splitting algorithmfor acoustic and gravity waves.The model physical parameterization includes a K-theory subgrid eddy mixing for cloudand free atmosphere,a bulk planetary boundary layer parameterization,and three types of sofisticated cloudmicrophysics schemes with double-parameters for hail-bearing clouds,warm clouds and snowing clouds respectively.The model is designed to be used flexibly for simulations of a variety of meso-and small-scale atmospheric processes,and can be improved as a regional and local operational NWP system in future.     

浅议地勘单位的物业管理

文章阐述了地勘单位物业管理社会化的必然性和内函 ,提出发展地勘单位物业管理的基本内容和需要解决的问题 ,最终实现以业养业 ,自我发展。     

地球化学景观吸引子的发现及其意义

勘查地球化学对异常评价的最大不确定性源于对地球化学景观特性的认识不够。我们应用构造相空间的方法分析了浙江儒岙幅（1:5万）水系沉积物测量的Ag含量数据，揭示了地球化学景观是具有低维吸引子（DZ≈2．9）的混饨系统。这一发现将对勘查地球化学中采样密度的选择、地球化学场模拟、异常评价等根本性问题产生重大影响。     

高、低煤阶煤层气藏地质特征及控气作用差异性研究

高、低煤阶煤层气地质特征及控气作用差异性是研究煤层气富集成藏的重要组成部分,是煤层气勘探开发理论研究过程中重要的基础性研究领域之一。本文以中国沁水、阜新盆地和美国粉河盆地等典型的含气盆地为例,探讨了高、低煤阶煤层气的储层物性差异,分析了构造控气和水文地质控气作用的差异性。研究表明,高煤阶气藏含气量高,CH4百分含量高,δ13C1值大于-38.75‰,储层渗透率变化小,储层改造难,构造热事件对煤层气的生成、富集贡献大,持续的水动力使气藏遭到破坏,且破坏幅度大,现今地下水格局对气藏的形成具有一定的影响;低煤阶气藏含气量低,CH4百分含量低,δ13C1值大于-49.11‰,储层渗透率变化大,储层易改造,煤热演化史及煤阶影响着煤层气的生成、富集,在煤层气生成过程中活跃的水动力是甲烷生成的主要的水文地质条件之一,但持续的水动力使气藏遭到破坏,且破坏幅度小,而合适的地层水矿化度则是低煤阶煤层气生成的重要条件,地下水格局对气藏的调整和改造起到决定性的影响。     

南海西部海域新生代构造古地理演化及其对油气勘探的意义

南海西部海域构造复杂,主要发育有北东—北东东向、北西向和近南北向3组深大断裂。其中,北西向断裂与板块汇聚、碰撞有关,多具走滑性质;北东—北东东向断裂具有与中国东部裂谷盆地相似的发育特点,呈张扭性质;近南北向断裂可能是南海在扩张活动期间于洋、陆壳过渡部位形成的走滑调节断裂,是洋盆扩张的西部边界。新生代里,南海经历了4次成盆事件与3期扩张活动,盆地经历了古新世—中始新世陆缘断陷、渐新世—早中新世扩展与中中新世以来的热沉降3个演化阶段。陆缘断陷阶段的充填系列主要是北东—北东东向与北西向的河流—冲积扇、湖泊沼泽等陆相沉积及火山岩等;盆地扩展阶段表现为中-小型断陷、断-坳陷逐渐复合与联合为大-中型坳陷,古地理格局逐渐由河流与湖沼陆相环境演变为滨海至浅海相的沉积环境;热沉降阶段的成盆活动逐渐减弱以至停止,地层表现超覆,盆地出现联合迹象。结合以往勘探与油气资源调查成果分析,认为南海西部海域陆架陆坡区发育的大-中型沉积盆地石油地质条件良好,蕴藏着丰富的油气资源,勘探潜力巨大。     

渤海新近系浅水三角洲沉积体系与大型油气田勘探

新近纪渤海具有构造稳定、沉降缓慢、湖泊水域范围大、内部无分割、地形平缓、坡度小等特点,广泛发育浅水三角洲,从而形成渤海海域新近系良好的储盖组合和优越的油气成藏条件。浅水三角洲砂岩储层由于受河流作用的控制,砂体具有明显的方向性,存在明显的分叉现象,与曲流河相比,砂体连通性较好,砂体等厚图呈典型的朵叶状。湖相厚层泥岩普遍发育,与浅水三角洲砂体组成多套垂向优质储盖组合。浅水三角洲发育于渤海新近纪至今处于生烃的峰期主力富烃凹陷的有利区带,新构造运动造成新近纪以来凹陷主力源岩生烃峰期与新构造运动的同步耦合,为渤海大型浅水三角洲成因的优质储层油气成藏创造了优越条件,可以形成大型油气田。因此,重视并充分挖掘渤海浅水三角洲储层类型油气藏的勘探潜力将是追求浅层优质油藏、进一步增储上产的方向所在。