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21.
岩石分类一直是人们长期探索的课题。由于油气勘探的需要,针对储层研究的盆地火山岩分类已经成为火成岩研究的重要新方向。在综合分析国内外火山岩分类研究的基础上,根据3条野外剖面和21口钻井岩心岩屑的观察描述、岩石薄片鉴定和化学成分分析等资料,依照结构-成分-成因分类原则,建立了适于储层评价的准噶尔盆地石炭系火山岩及其他岩类的岩性分类体系和识别标准。将本区火山岩划分为火山熔岩、火山碎屑熔岩、火山碎屑岩、沉火山碎屑岩等4大类;同时将盆地内与火山岩共生的其他岩类也进行分类和识别,共划分出8大类45种基本类型。与我国东部的中新生代盆地火山岩不同,本区古生代火山岩普遍遭受较长期风化改造和蚀变作用,常见有绿泥石化、碳酸盐化和黏土矿化。这些蚀变会影响到TAS图解岩性判别的结果,因此笔者探讨了蚀变条件下的岩石识别和定名方法。本文分类体系针对火山岩储层研究,结果显示,基于该分类体系岩性与储集空间的类型及其变化规律呈现明显相关性,不同岩性的储集空间类型、组合方式和发育程度存在差异,由此可指导火山岩油气勘探。  相似文献   
22.
边艳  周春山  胡锦灿 《热带地理》2020,40(5):832-842
以2014年广州市中产阶层聚居区24个街道、50个社区进行的问卷调查和深度访谈资料为数据源,从住房需求意愿与区位选择方面分析了广州中产阶层住房选择,并运用多元Logistic回归分析法对其影响因素进行研究。研究发现:1)广州市中产阶层住房区位选择表现出明显的“向中心城区”性;2)现居住现状(人均住房面积、现小区区位、现小区建成年代、现居住时间)、家庭生命周期(年龄、家庭规模、子女数量)和经济水平(家庭年总收入、个人年总收入、私家车拥有量)等因素对中产阶层住房需求意愿具有显著影响;3)家庭生命周期(年龄、家庭规模)、个体因素(教育程度、户籍地)等要素对中产阶层住房区位选择具有显著影响。4)制度因素、区位因素和个体因素共同影响着广州市中产阶层住房区位选择。  相似文献   
23.
Brightness temperature is a main index to reflect the energy of microwave radiation of an object. Using lunar brightness temperature data, physical properties of lunar regolith, such as thickness, heat flow and dielectric permittivity, could be interpreted. There are two methods to study brightness temperature distribution of the moon: the first is used to measure lunar brightness temperature by radio observation or spaceborne microwave radiometers, and the second is used to simulate calculation by the physical model. On the basis of the measurements of lunar brightness temperature in the history, this study analyzed the main physical model of lunar brightness temperature, also including its theory and influence factors. The authors concluded that surface and subsurface temperatures of the moon, dielectric properties and layered structure of lunar regolith were the main factors affecting the global brightness temperature of the moon. These factors should be quantified in detail in the future research.  相似文献   
24.
The development of interoperable environmental process models is widely supported by both the research community and government agencies. This paper discusses a conceptual framework to guide the delineation of process components, the basic unit of interoperable models. The concepts of semantic reference system and dual hierarchy are explored to establish the conceptual framework. Based on this discussion, the Formal Concept Analysis is used as an analytical approach to decompose and fuse existing environmental process models in order to identify environmental process components. For purposes of discussion, a hydrological process, surface runoff, is used throughout the paper as an example of an environmental process to support the conceptual discussion and to illustrate the application of the conceptual framework and analytical approach.  相似文献   
25.
System dynamics (SD) theory has long been deployed in modeling complex non-linear interrelationships but, so far it has not been common to do the kind of modeling in support of bringing environmental sustainability policies to practice. This is largely because the challenge of including spatial data has not yet been well met. Potential for adoption of SD and GIS methods in combination is exemplified with the results of a decision-support exercise designed for simulation and prediction of the dynamic inter-relationships between socio-economic development and environmental quality for the “Wen, Pi, Du” county in Sichuan province, southwestern China.  相似文献   
26.
Hao Li  Ling Bian  Teng Wang 《国际地球制图》2016,31(10):1058-1077
Geospatial services with different functions are assembled together to solve complex problems. Different taxonomies are developed to categorize these services into classes. As differences in granularity and semantics exist among these taxonomies, the identification of services across different taxonomies has become a challenge. In this paper, an approach to identify geospatial services across heterogeneous taxonomies is proposed. Using formal concept analysis, existing heterogeneous taxonomies are decomposed into semantic factors and their various combinations. With these semantic factors, a super taxonomy is established to integrate the original heterogeneous taxonomies. Finally, with the super taxonomy as a cross-referencing system, geospatial services with classes in original taxonomies are identifiable across taxonomies. Experiments in service registries and a social media-based spatial-temporal analysis project are presented to illustrate the effectiveness of this approach.  相似文献   
27.
礁滩体与建设性成岩作用   总被引:9,自引:0,他引:9       下载免费PDF全文
礁、礁丘、丘同属碳酸盐建隆,礁、滩是重要勘探目的层。但各自在沉积组分、组构、环境和时空分布,以及油气地质条件上迥然不同,因而无论从理论还是勘探实践上,都有必要将其各成体系划分开来。礁滩自身为好储集岩,当建设性成岩作用叠加后可形成好的储层。碳酸盐岩优质储层形成,主要受沉积微相与建设性成岩作用两大因素控制。前者是基础,并以高能的礁滩相带为最好;后者主要包括破裂、白云石化和溶蚀三大类,并以白云石化或溶蚀为最优,其中的溶蚀分布最广泛、影响最深刻而对优质储层形成起决定性作用。礁滩储层中的古岩溶类型最为丰富多彩,包括同生期、准同生期、表生期和埋藏期热流体岩溶的所有类型,白云岩化礁滩体也不例外。其中,同生-准同生期岩溶的形成机制与礁滩沉积时高频层序旋回向上变浅序列的短暂暴露淋溶有关,表生期岩溶则受控于礁滩沉积后三级层序旋回Ⅰ型界面的暴露淋溶。由此,导致礁滩储层中除了可以也是(碳酸盐岩中)唯一保存原生孔隙外,还发育了次生溶蚀孔洞缝和大型溶洞。礁丘、灰泥丘尤其是丘间洼地中发育高有机质丰度烃源岩;它们自身没有有效的原生孔隙,但岩溶作用可以形成次生孔隙。  相似文献   
28.
Although there has been substantial research done on adsorption of metals/metalloids by Al (oxy)hydroxides, little is known regarding the adsorption of polyaromatic hydrocarbons (PAHs) on Al (oxy)hydroxides, especially those formed in the presence of organic acid. This paper investigated the adsorption of phenanthrene on Al (oxy)hydroxides formed with initial tannate/Al molar ratios (MRs) 0, 0.001, 0.01, and 0.1 (referred to MR0, MR0.001, MR0.01, and MR0.1, respectively) through batch adsorption experiments and FTIR study. The results showed that Al (oxy)hydroxides were important sorbents for phenanthrene. The adsorption kinetic data were fitted well with the pseudo-second-order equation. According to a modified Freundlich model, the adsorption capacities of Al (oxy)hydroxides followed a descending order of MR0.1 > MR0 ≥ MR0.01 > MR0.001, which was inconsistent with the organic carbon content in the Al (oxy)hydroxides. Adsorption capacity correlated with the specific surface area, micropore area, and micropore diameter of Al (oxy)hydroxides, yet the relationships were not statistically significant (P > 0.05). FTIR results showed that physical interaction was essential in phenanthrene adsorption onto the Al (oxy)hydroxides, which could be explained by an entropy-driven process. Surface hydrophobicity of Al (oxy)hydroxides played a key role in phenanthrene adsorption. Additional π–π electron donor–acceptor interaction of phenanthrene (acting as electron donor) with aromatic ring of tannic acid (electron acceptor) could be also important in phenanthrene adsorption by high MR Al (oxy)hydroxides, yet it needs further study. The findings obtained in the present study are of fundamental significance in understanding the mechanism of immobilization of PAHs in low organic matter but oxide-rich soils.  相似文献   
29.
准确而可靠地预测地下水埋深对生态环境保护和水资源规划管理具有重要意义。针对吉林西部浅层地下水位动态变化的复杂性和非线性,提出了基于小波分析与人工神经网络相结合的预测方法小波神经网络(WA-ANN)模型。将研究区2002年1月2009年12月当月降水量、蒸发量、人工开采量和前月平均地下水埋深4个参数作为输入,当月平均地下水埋深作为输出,建立浅层地下水埋深预测模型,并与BP神经网络(BP-ANN)模型和自回归移动平均(ARIMA)模型进行比较,对比分析了三者的建模过程及其模拟精度。结果显示:相比两种ANN模型,ARIMA模型建模过程更为简单,计算效率更高;但WA-ANN模型的拟合精度高于BP-ANN和ARIMA模型,预测效果更好。总体来看,WA-ANN模型在浅层地下水埋深预测中具有一定的应用推广价值。  相似文献   
30.
额尔古纳造山带构造演化与成矿作用   总被引:18,自引:0,他引:18       下载免费PDF全文
额尔古纳造山带属加里东期造山带。因该造山带发育了一系列燕山期铜多金属矿床,并且它位于着名的得尔布干深断裂带的西北侧,故也称为得尔布干成矿带。额尔古纳造山带属西伯利亚板块东南缘加里东期陆缘增生带。形成之后又经历了多期构造运动的改造,特别是燕山期沿得尔布干等北东向深断裂发生了大陆裂谷作用和强烈构造岩浆活动,使之最终形成了一系列不同类型的铜钼矿床和银多金属矿床。这些矿床在空间上构成“三层楼”结构。本文阐明了额尔古纳造山带成矿作用的重要地质因素,表明成矿作用是多期复杂地质构造作用的综合结果。  相似文献   
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