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251.
This paper documents a new method for describing channel-related sedimentary deposits based on formal language theory. Using this method an analogue model of a sedimentary deposit can be encoded as a grammar. A program, called a parser, has been developed which can generate stochastic maps of these sedimentary deposits based on information in a specified grammar. The maps of sedimentary deposits generated by the parser have the same type, spatial arrangement, shape and size distribution as the analogue model. The successful generation of depositional maps represents a crucial step in the ongoing development of a new technique designed to generate 3D static geological models of sedimentary successions. The maps can be conditioned to match sparse hard data in the form of channel segments interpreted from seismic horizon maps. 相似文献
252.
On the basis of the soil environment investigation in Da'an City, Jilin Province, China, 40 soil samples from main land use types were obtained and tested by standard method. Soil organic matter (SOM), total N (TN), total P (TP), total K (TK), available N (AN), available P (AP) and available K (AK) were chosen as the evaluation factors. A regional soil nutrient evaluation model was developed based on the matter-element model. The results show that the soil samples with nutrient grade Ⅱ-Ⅴ respectively account for 10%, 30%, 32.5% and 27.5%, and those with grade Ⅳ and Ⅴ account for 60% in all samples. The relationship between soil nutrients and land types indicates that the nutrients of farmland are relatively good, with 41.7% of soil samples with the nutrient grade Ⅳ and Ⅴ. The nutrients of saline-alkali land and sandy land are the worst, with 100% of soil samples with the nutrient grade Ⅳ and Ⅴ. And the ratios of soil samples grade Ⅳ and Ⅴ in grassland and wasteland are respectively 62.5 % and 54.55%. Generally speaking, the soil nutrients status in Da'an City is poor, 60% of soil samples are in poor and extremely poor conditions, indicating that the soil has been severely eroded. Being a relatively superior evaluation method with more accurate resuits and spatial distribution consistency, matter-element analysis is more suitable for regional soil nutrient evaluation than previous models. 相似文献
253.
地图概括中空间目标几何信息传递模型研究 总被引:1,自引:0,他引:1
地图概括是实现多比例尺地图生产和更新的一种重要理论方法。目前,国际国内制图学界对地图概括的研究主要集中在发展地图概括算法方面,在地图概括的质量评价方面的研究还很少。为此,本文以信息论为理论基础,以地图概括中空间目标几何信息的传递问题为研究对象,以相应空间目标几何信息的传递效率来度量地图概括中单个空间目标的概括质量。首先,建立了地图概括的空间信息传递模型,描述不同比例尺地图之间空间信息的传递过程。进而提出了地图概括过程中空间目标(即:线和面目标)几何信息的传递模型,并且对地图概括中空间目标几何信息的传递状况进行了评估,给出了具体的计算和实现方法。最后,通过实验初步验证了地图概括中空间目标几何信息传递模型的可行性。 相似文献
254.
�봨8.0������ͬ���������α�ЧӦģ�� 总被引:7,自引:4,他引:7
???????λ??????????е???????????????????Ms8.0???????????????????仯?????????????????????λ????????????????????????α?仯?????????????????????????????????????????仯????,????????????????????????????????????α?????????????????????????????仯?????10??10 -8 ms -2???£??????????仯??????????50??10 -8 ms -2????????????????????????? 相似文献
255.
本文概述了新、老矿区的战略找矿方向和基础理论找矿模式,提出测试、钻探及最佳找矿技术方法组合,强化组织管理是地质勘查的正确思路 相似文献
256.
海洋鱼类分子系统地理学研究进展 总被引:1,自引:0,他引:1
简要叙述了分子系统地理学的发展简史、研究内容,重点介绍了Avise的5种物种分布模式及中性溯祖理论。并回顾了近年来分子系统地理学的研究进展及其在海洋鱼类研究中的应用,最后对海洋鱼类分子系统地理学研究进行了展望。 相似文献
257.
Arun K. Saraf Vineeta Rawat Swapnamita Choudhury Sudipta Dasgupta Josodhir Das 《International Journal of Applied Earth Observation and Geoinformation》2009
Stresses building up during an earthquake preparation phase also manifest themselves in the form of a so called increased land surface temperature (LST) leading to a thermal precursor prior to the earthquake event. This phenomenon has now been validated by our observations of short-term thermal anomalies detected by infrared satellite sensors for several recent past earthquakes around the world. The rise in infrared radiance temperature was seen to vary between 5 and 12 °C for different earthquakes. We discuss in this paper different explanations for the generation of such anomalies that have been offered. Emission of gases due to the opening and closure of micropores upon induced stresses and also the participation of ground water have been propounded as a possible cause for generation of thermal anomalies. Seismo-ionosphere coupling, by which gases like radon move to the earth–atmosphere interface and cause air ionization thus bringing about a change in air temperature, relative humidity, etc., has been put forth by some workers. A mechanism of low frequency electromagnetic emission was tested and experimented by scientists with rock masses in stressed conditions as those that exist at tectonic locations. The workers proposed the positive hole pair theory, which received support from several scientific groups. Positive holes (sites of electron deficiency) are activated in stressed rocks from pre-existing yet dormant positive hole pairs (PHPs) and their recombination at rock–air interface leads to a LST rise. A combination of remote sensing detection of rock mechanics behavior with a perception of chemistry and geophysics has been applied to propose the remote sensing rock mechanics theory. Remote sensing detections of such anomalies confirm so far proposed lab theories for such a hotly debated field as earthquake precursor study by providing unbiased observations with consistency in time and space distribution. 相似文献
258.
基于云理论、粗集和模糊神经网络的区域橡胶种植适宜度评估模型 总被引:1,自引:0,他引:1
针对橡胶种植适宜性评估,基于云理论、粗集理论和模糊神经网络理论,提出了一种适宜度评估模型。该模型将转化的样本数据进行粗集简约,通过模糊神经网络得出评价因子的隶属函数,计算评价等级。研究结果表明,此模型能够科学、快速、准确地分析出橡胶种植最适宜区、适宜区、次适宜区和不适宜区。 相似文献
259.
260.
对秦岭造山带区域成矿背景、矿床的时空分布、典型矿床矿田赋存部位、区域成矿元素地球化学背景、多重岩片控矿理论,构造成矿体系、成矿物质来源、矿床成因类型、矿床区域成矿模式进行了讨论,在对大量资料研究的基础上提出了新认识。最后指出秦巴地区进一步寻找大型矿床的地区。 相似文献