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151.
非常规综合物化探方法油气预测研究中存在的主要问题为:缺乏系统与综合的基础性理论研究,异常形成的机理还不十分清楚,在参数的优化组合及异常的求取上尚有诸多不足。针对后一种情况,选择松辽盆地东岭构造作为实验区进行了有益的探索。选取低能吸附烃、放射性测氡及土壤热释光三类参数进行了优化组合,分别计算了综合指标MAE与MAC及组合熵,然后对各值采用泛克里格法求取异常,取得了良好的效果。下一步研究应从异常形成的机理入手,建立三维非常规综合物化探油气预测模式,以提高油气预测成功率。 相似文献
152.
海底天然气渗漏形成水合物量的线性动力学模型:以墨西哥湾GC185区块Bush高地为例 总被引:7,自引:1,他引:7
世界许多地区如墨西哥湾,存在着大量天然气渗漏并形成水合物的现象,出于科学,生态,气候和安全的需要。人类有必要弄清存在于海底以水合成形式存在的天然气的比例。因此,构建了水合物形成量的线性动力学模型,以分析墨西哥湾GC185块区Bush高地海底渗漏天然气的地质过程和行为。Bush高地渗漏的天然气来源于附近的Jolliet气藏,结果表明,渗漏天然气中约有9%的海底形成了水合物。 相似文献
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154.
The application of variations in the earth's gravity in groundwater exploration on a regional scale, especially in sedimentary
basins, metamorphic terrains, valley fills, and for buried alluvial channels, is well established. However, its use in hard
crystalline rocks is little known. In granite, for example, the upper weathered layer is a potential primary aquifer, and
the underlying fractured rock can form a secondary aquifer. Fracturing and weathering increases the porosity of a rock, thereby
reducing the bulk density. Changes in gravity anomalies of 0.1–0.7 mGal for granites, due to weathering or variations in lithology,
can be detected.
To test the use of gravity as a groundwater exploration tool for crystalline rocks, a gravity survey of the peninsular shield
granites underlying Osmania University Campus, Hyderabad, India, was undertaken. At the site, gravity anomalies reflect variations
in the lithology and in the thickness of weathered zones. These anomalies also define the position of intrusives and lineaments.
Areas of more deeply weathered granite that contain wells of higher groundwater yield are represented by negative gravity
values. In the weathered zone, well yield has an inverse relation to the magnitudes of residual gravity. The study confirms
the feasibility of gravity as a tool for groundwater exploration in crystalline rocks.
Electronic Publication 相似文献
155.
Shahid Naseem Shamim Ahmed Sheikh M. Qadeeruddin Khaula Shirin 《Journal of Geochemical Exploration》2002,76(1)
A pilot scale geochemical survey of sediments from the Winder Stream (SW Pakistan) and its tributaries was carried out. The Winder Stream mainly receives sediment from the southern extensions of the Mor and Pab Ranges in the District of Lasbela (Balochistan). In these two mountain ranges, rocks from Jurassic to Cretaceous age are exposed. Rocks of the Ferozabad Group comprise of carbonates and siliciclastics of Lower–Middle Jurassic age and occupy the dominant part of the Mor Range. These strata host syngenetic and epigenetic Zn–Pb–Ba mineralizations of Stratiform Sediment-Hosted (SSH) and Mississippi Valley Type (MVT) deposits.Quantitative estimates of mobile and immobile elements were made from active stream sediments of the Winder stream and its tributaries. The samples were analyzed for Ag, Zn, Pb, Cu, Ni, Co, V, Mn, Fe and Ba using atomic absorption spectroscopy. The abundance of these elements is discussed in relation to local geological conditions such as bedrock, climate, weathering, mobility and pH of the dispersing waters. A number of Zn anomalies have been distinguished in the study area. Kharrari (Zn, 360 ppm), Sand (Zn, 340 ppm) and Draber (Zn, 210 ppm) are demarcated as new areas for Zn mineralization. The present study also indicates prospects of Ag, Cu and V in the rocks of the Mor Range.Relationships between various elements have been identified from scattergrams and reflect genetic associations. Whereby the positive correlation between Cu–Zn (0.55, n=18) and Cu–Pb (0.63) is related to possible sulphide mineralization. 相似文献
156.
This paper presents the results of a study undertaken todetermine the seismic hazard of Lebanon. The seismic hazard evaluation wasconducted using probabilistic methods of hazard analysis. Potential sourcesof seismic activities that affect Lebanon were identified and the earthquakerecurrence relationships of these sources were developed from instrumentalseismology data, historical records, and earlier studies undertaken toevaluate the seismic hazard of neighboring countries. The sensitivityof the results to different assumptions regarding the seismic sources in theLebanese segment and choice of the attenuation relationship wasevaluated. Maps of peak ground acceleration contours, based on 10percent of probability of exceedance in 50 years and 100 years time spans,were developed. 相似文献
157.
This paper describes briefly the recent advances and acievements of the research projects conducted by the Institute of Engineering Mechanics(IEM) in the period of the Ninth Five-Year Plan(1995-2000) with the support of the China Seismological Bureau(CSB),These projects are related with key problems in the field of earthquake engineering.They are:development of the methods for determining earthquake resistant design load level,study on mechanisms of earthquake damage to buildings.development of new technology of base isolation,and study on earthquake damage prediction and seismic losss assessment methods.Through these studies,quite a number of problems have een solved and some of them have een applied in earthquake engineering design and practice. 相似文献
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马蔼乃 《地理与地理信息科学》2002,18(2):41-44
该文指出 :王化云的治黄思想 ,“上拦下排、两岸分滞、蓄水拦沙、宽河固堤、除害兴利、综合利用” ,实际上是治理黄河的系统工程 ,2 1世纪应该继承和发展黄河系统工程的方略。黄河地处中国腹地 ,是中华民族的摇篮 ,当今高新科技的发展 ,足以从更大的范围 ,以全国的水资源、土资源为核心来考虑黄河的建设。统一计算水资源中的大气水、地表水、地下水、壤中水、生态水、环境水、生产水、生活水 ;统一计算土资源中的土壤资源、沙资源、沙石资源 ,真正按照地理系统工程来建设黄河。 相似文献