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81.
中国海相探矿权区块定量评价方法   总被引:2,自引:0,他引:2  
在研究了我国海相油气探矿权区块基本油气地质条件、勘探程度、技术经济条件等要素和特点的基础上,给出了48个评价参数和归一化取值参照表,建立了探矿权区块评价工作流程、评分参数及计算公式。提出对我国海相勘探层探矿权区块评价应该注意:与国外海相碳酸盐岩评价的差别;与国内陆相碎屑岩评价的差别;成藏组合的划分;评价内容的有效性、不确定性和评价参数的可信度;成败经验的总结和勘探程度的研究。  相似文献   
82.
将安全、和谐、环境、经济和是否占有资源等指标作为评价城市地质质量的5个因子,并以河南省郑州、平顶山、焦作、鹤壁四个主要城市为例,在调查分析了城市存在的自然地质因素(地质构造、岩土)和人为活动影响次生因素等主要问题基础上,建立起自然地质因素、人为次生因素等与5个评价因子之间的逻辑联系;根据地质因素对城市因子的影响程度的轻重,进行专家赋值判别运算,采用层次分析法(AHP))进行权重分析,对四个城市的城市地质质量进行了评估。结果认为Z-Ⅰ、Z-Ⅱ、J-Ⅱ、H-Ⅰ、H-Ⅱ、P—Ⅱ、P—Ⅲ、H—Ⅲ等区良好以上,适宜城市可持续发展;P—Ⅰ、H-Ⅳ等区质量不高,存在问题较多,应在城市建设发展中引起注意。同时指出城市地质是城市发展中的一个重要的基本因素,城市的建设、可持续发展方案的制定需要关注城市地质质量、依赖城市地质。  相似文献   
83.
新疆天山公路(国道217线)是连接南、北疆的一条重要交通干线。通过调查研究沿线的地质条件,采用多元线性回归分析方法,选取地层岩性、地面坡度、相对高差、构造密度、多年平均降雨量、冻融作用、地震强度、植被覆盖率、开挖深度、灾害的分布密度和规模大小等11个评价因子,建立了地质灾害危险性级别的评价模型,得出了公路沿线的危险性级别图。  相似文献   
84.
靖远矿区采煤沉陷区复垦综合评价方法研究   总被引:1,自引:0,他引:1  
以靖远矿区为例,从土地复垦和恢复生态学的角度出发,建立了靖远矿区采煤沉陷区复垦综合评价系统,选择土壤条件(土层厚度、土壤质地、有机质含量、土壤水分)、地形改造条件(地面坡度、地表破坏程度、改造难易程度)、气候及水文条件(年降雨量、灌溉条件)作为分类及评价因子对复垦潜力进行评价。将采煤沉陷地分为四种潜力区,对每种潜力类型区的复垦开发利用方向进行了优化设计,从理论上和实践上对靖远矿区采煤沉陷地的复垦能力以及复垦过程中用地结构的优化作了探讨,以期对当地沉陷地的复垦提供一定的科学依据。  相似文献   
85.
Summary The newly developed light sectioning method has been used to investigate some of the causes and costs of overbreak and underbreak. Investigations at the Aquamilpa Hydroelectric Project in Mexico have shown decreased overbreak and increased underbreak as a result of increased rock quality and decreased explosive energy. A new measure of explosive energy, the perimeter powder factor (PPF), has been defined and shown to be useful in the context of tunnel-wall rock damage. Tentative results indicate that explosive energy (PPF) may be a more important factor in producing underbreak, whereas rock quality may be a greater factor in producing overbreak. A site-specific equation is given for predicting overbreak or underbreak as a function of rock quality and explosive energy, with an evaluation of the cost of underbreak and overbreak.  相似文献   
86.
Two widely-used techniques to estimate the volume of remaining oil and gas resources are discovery process modeling and geologic assessment. Both were used in a recent national assessment of oil and gas resources of the United States. Parallel estimates were obtained for 27 provinces. Geological-based estimates can typically see into areas not available to discovery process models (that is areas with little or no exploration history) and thus, on average, yield higher estimates. However, a linear relation does exist between the mean estimates obtained from these two methods. In addition, other variables were found in a multiple regression model that explained much of the difference. Thus, it is possible to perform discovery process modeling and adjust the estimates to yield results that might be expected from geological-based assessments.  相似文献   
87.
Wang  Yutian  Tan  Bingqi  Wang  Yifeng  Wu  Jiangtao 《Natural Resources Research》1994,3(4):284-294
We propose an information-structure-analysis (ISA) method to quantify the correlations between quantitative and qualitative variables as well as within each type of variable. This method is applied to the evaluation of mineral resources in the western Zheijiang Province of China. The district contains a number of silver-bearing Fe–Cu–Pb–Zn mineral deposits near igneous complexes and FeCuPbZn zones away from the complexes. Silver anomalies occur not only in the known Fe–Cu–Zn–Pb deposits, but also in the country rock, suggesting the possible existence of silver deposits far from the igneous complexes.The tonnage distribution of silver is modeled by Monte Carlo simulation. This simulation is conducted on the basis of the correlations between silver (Ag) and lead (Pb), since no known data on silver is available. The known tonnage distribution of lead in 11 control cells was used to approximate the tonnage distribution of silver in the Monte Carlo simulation. With ISA and Monte Carlo methods, the total amount of potential polymetallic resources in 49 cells in the western Zhejiang Provice is predicted. Significantly, a deposit with about 24 tonnes of silver has been found within our exploration target area.  相似文献   
88.
张少泉  吕庆书 《地震》1993,(5):47-61
首都减灾圈,系首都减轻自然灾害预测防治圈。1991年12月20—21日在北京召开了《首都圈自然灾害及其减灾对策研讨会》。本文根据这次会议所提供的材料,在从整体上实现减灾的思想指导下,就首都减灾圈的“成灾背景”、“首都减灾圈的组成”、“首都减灾圈的灾害预测与防治状况”、“首都减灾圈的灾害关联性分析”、“首都减灾圈的减灾实效预估”和“首都减灾圈的减灾对策与实施”等六个带有共同性的问题,进行了讨论。供制定首都圈减灾方案时参考。  相似文献   
89.
We report on an objective methodology, referred to as intrinsic sample methodology, for the delineation of exploration target areas or resource areas for assessment. Important features of the methodology include (1) identification of recognition criteria for critical genetic factors, (2) synthesis of new variables from enhanced geodata, (3) estimation of logit probability models, and (4) cutting of estimated logit probabilities to delineate exploration targets or resource areas. The methodology is demonstrated on the Walker Lake quadrangle of Nevada and California.  相似文献   
90.
The deposit size frequency (DSF) method has been developed as a generalization of the method that was used in the National Uranium Resource Evaluation (NURE) program to estimate the uranium endowment of the United States. The DSF method overcomes difficulties encountered during the NURE program when geologists were asked to provide subjective estimates of (1) the endowed fraction of an area judged favorable (factorF) for the occurrence of undiscovered uranium deposits and (2) the tons of endowed rock per unit area (factorT) within the endowed fraction of the favorable area. Because the magnitudes of factorsF andT were unfamiliar to nearly all of the geologists, most geologists responded by estimating the number of undiscovered deposits likely to occur within the favorable area and the average size of these deposits. The DSF method combines factorsF andT into a single factor (F·T) that represents the tons of endowed rock per unit area of the undiscovered deposits within the favorable area. FactorF·T, provided by the geologist, is the estimated number of undiscovered deposits per unit area in each of a number of specified deposit-size classes. The number of deposit-size classes and the size interval of each class are based on the data collected from the deposits in known (control) areas. The DSF method affords greater latitude in making subjective estimates than the NURE method and emphasizes more of the everyday experience of exploration geologists. Using the DSF method, new assessments have been made for the young, organic-rich surficial uranium deposits in Washington and idaho and for the solution-collapse breccia pipe uranium deposits in the Grand Canyon region in Arizona and adjacent Utah.  相似文献   
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