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991.
在台址下电阻率分层均匀的前提下,针对我国绝大多数前兆地电台单极距观测的事实与现状,提出一种试图从这种观测所获得的视电阻率时间序列中识别电阻率表层变化和深部变化的等效模型方法.分析表明,在保持布极方式和观测结果不变的前提下,任意多层的地电结构都可以视为一个二层地电结构——等效模型.本文中,等效模型上层的地电参数(电阻率和厚度)与实际模型第一层相同,下层的地电参数(电阻率)则根据等效要求,由实际模型第二层及其以下各层的地电参数经计算得到,因此,等效模型的下层包含了实际模型第二层及其以下各层的综合影响.初步研究表明,这种方法是可行的. 相似文献
992.
993.
Quantitative Analysis of Mineral Resources for Strategic Planning: Implications for Australian Geological Surveys 总被引:5,自引:0,他引:5
A quantitative valuation study has been made of Australian state surveys with the specific goals of (1) establishing the 'worth' of current programs upgrading state government geoscientific information infrastructure, and (2) considering the results of the valuation in terms of strategic planning. The study has been done from the perspective of the community as a whole and has been undertaken in two phases reflecting the different objectives of Australian state surveys in terms of the exploration industry and government policy-making. This paper reports on the second part of this valuation process, measuring the impact of upgraded survey data on government mineral policy decision processes. The valuation methodology developed is a comparative approach used to determine net benefit foregone by not upgrading information infrastructure. The underlying premise for the geological survey study is that existing and upgraded data sets will have a different probability that a deposit will be detected. The approach used in the valuation of geoscientific data introduces a significant technical component with the requirement to model both favorability of mineral occurrence and probability of deposit occurrence for two different generations of government data. The estimation of mineral potential uses modern quantitative methods, including the U.S. Geological Survey three-part resource-assessment process and computer-based prospectivity modeling. To test the methodology mineral potential was assessed for porphyry copper type deposits in part of the Yarrol Province, central Queensland. Results of the Yarrol case study supports the strategy of the state surveys to facilitate effective exploration by improving accuracy and acquiring new data, as part of resource management. It was determined in the Yarrol Province case study that in going from existing to upgraded data sets the area that would be considered permissible for the occurrence of porphyry type deposits almost doubled. The implication of this result is that large tracts of potentially mineralized land would not be identified using existing data. Results of the prospectivity modeling showed a marked increase in the number of exploration targets and in target rankings using the upgraded data set. A significant reduction in discovery risk also is associated with the upgraded data set, a conclusion supported by the fact that known mines with surface exposure are not identified in prospectivity modeling using the existing data sets. These results highlight the absence in the existing data sets of information critical for the identification of prospective ground.Quantitative resource assessment and computer-based prospectivity modeling are seen as complementary processes that provide the support for the increasingly sophisticated needs of Australian survey clients. Significant additional gains to the current value of geoscientific data can be achieved through the in-house analysis and characterization of individual data sets, the integration and interpretation of data sets, and the incorporation of information on geological uncertainty. 相似文献
994.
资源场理论及其在资源流动中的应用 总被引:23,自引:0,他引:23
借鉴物理学中的场思维,构建了资源场理论分析框架,探索了资源流动的力的本质:资源势差是资源流动的内在本质,资源场力是推动资源流动的本质力量,资源场力和外力的合力是资源流动的直接力量。利用资源场论分析了山水省宁津县宁津镇、张学武乡劳动力资源地域流动和部门流动的情况和趋势。 相似文献
995.
烃源岩中矿物沥青基质成烃潜力探讨 总被引:4,自引:1,他引:4
烃源岩中存在大量矿物沥青基质,目前对其成烃潜力知之甚少。本文以酒东盆地侏罗系和白垩系烃源岩为例,从矿物沥青基质与有机显微组分,无机矿物、有机质丰度、有机质类型,有机质成熟度的关系及其荧光变化特点探讨其组成及成烃潜力,结果表明,矿物沥青基质中有机质含量低,且以次生有机质为主,原生有机质含量较少,成烃潜力有限。 相似文献
996.
西藏羌塘地区火山岩主要见于第三系石坪顶组,主要岩石类型是呈熔岩被产出的火山熔岩,包括辉石粗安岩、角闪粗面岩、角闪英安岩、黑云母英安岩等,其次可见次火山岩相的黑云母英安质碎斑熔岩和黑云母粗面质碎斑熔岩,以及辉石黑云母花斑岩.它们均为陆相中心式喷发的产物.岩石化学上属钾玄岩组合,可进一步分为钾玄岩系列和高硅钾玄岩系列,具非常典型的二元岩浆混合成因火山岩的岩石化学特征.其REE及微量元素特点表明二元岩浆混合前两个端元岩浆分别来自幔源和壳源.这些火山岩岩浆热事件对盆地有机烃类转化为石油和天然气是有利的,而破坏作用仅仅发生在火山机构附近 相似文献
997.
中国南方古油藏与油气评价 总被引:10,自引:4,他引:10
从早古生代至中、新生代,中国南部确实形成过相当数量和相当规模的油气藏。而后经较高的演化和多期次的构造运动,最终成为古油藏。如麻江、瓮安、泰山、米仓山、天井山、中和、龙街及小古山等古油藏。它展示了分布于中国南方各地质时期及各种地质条件下,油气藏形成、发展的全过程及其规律,充分揭示了油气藏的成藏、发展条件及破坏因素。因而运用其成藏规律,可以为油气远景评价、勘探部署做出重要的决策。 相似文献
998.
为研究不同沉积相源岩的生烃能力,选择宁夏灵武煤田延安组的对象,对其湖泊三角洲沉积体系下不同沉积相源岩进行热解分析,划分其生油岩类型或有机质类型,分析了不同沉积相源岩的生烃潜力。 相似文献
999.
Effect of Mixtures of Heavy Metals on the Biological Treatment of Sewages Containing Naphthalenesulfonic Acid Biological wastewater treatment processes can be destabilized considerably by heavy metals. In this investigation, the effect of loadings of heavy metals on the degradation of naphthalene-2-sulfonic acid (2NS) by immobilized bacteria in continuously operated airlift-loop reactors was studied. Shock loadings with mixtures of cadmium and nickel, or cadmium and zinc, respectively, resulted in increases in inhibition compared to those observed with the single metals. In contrast, the 2NS-degradation was less inhibited by shock loadings with mixtures of nickel and zinc than by the single metal ions. Repeated shock loadings up to 100 mg L?1 nickel and 1000 mg L?1 zinc effected an adaptation of the microorganisms. Continuous loadings with up to 10 mg L?1 cadmium and nickel each, or with 50 mg L?1 nickel and 210 mg L?1 zinc, respectively, did not inhibit the degradation of 2NS. The permanent loadings led to an adaptation of the bacteria with an increased biosynthesis of proteins from 0.2 to 0.5 g g?1 cell dry weight. However, if the immobilized cells were incubated with mixtures of cadmium and nickel, the specific polysaccharide content decreased to less than 0.2 g g?1 cell dry weight, resulting in a detachment of the biofilms. 相似文献
1000.
GIS APPLICATION IN RESEARCH OF WILDLIFE HABITAT CHANGE——A case study of the Giant Panda in Wolong Nature Reserve 总被引:2,自引:0,他引:2
Liu Xuehua Institute of Geography CAS Beijing People''s Republic of China M.C. Bronsveld A.G. Toxopeus M.S. Kreijns International Institute for Aerospace Survey Earth Sciences The Netherlands 《地理学报(英文版)》1997,(4)
I.IntroductionTheGiantPanda(Ailuropodamelanoleuea)isanendangeredanimalspeciesintheworld.Thereareabout1000individualsleftandconfinedintheisolatedmountainareasinthesouthwesternpartofChina.Itsremaininghabitatcoversabout29,500km2[2,6,11].Humanencroachmentisconsidere… 相似文献