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221.
不整合运移通道类型及输导油气特征   总被引:12,自引:1,他引:11  
高长海  查明 《地质学报》2008,82(8):1113-1120
在对不整合空间结构特征研究的基础上,提出了油气沿不整合运移的通道类型:宏观上,存在由不整合面之上底砾岩和不整合面之下半风化岩石两种高效运载层组合成的双运移通道型和单运移通道型两种通道类型;微观上,底砾岩连通孔隙、半风化岩石构造卸荷风化裂缝系统及溶蚀孔洞系统可作为油气运移的主要通道。通过对不整合面上、下岩石物性分析,认为半风化岩石“孔洞缝”系统较底砾岩连通孔隙有更高的输导油气的能力。研究结果表明,不同的运移通道类型具有不同的输导油气特征。在地史时期,构造裂缝系统和溶蚀孔洞系统一直是不整合输导油气的主要通道;对于软地层构成的不整合来说,开始应是卸荷、风化裂缝系统和底砾岩连通孔隙共同构成不整合输导油气的主要通道,当上覆沉积载荷达到一定程度后,主要是底砾岩连通孔隙起输导油气通道作用;对于脆硬地层构成的不整合来说,卸荷、风化裂缝系统和底砾岩连通孔隙一直是不整合输导油气的主要通道。  相似文献   
222.
鄂尔多斯盆地东缘煤储层微孔隙结构特征及其影响因素   总被引:2,自引:0,他引:2  
张松航  汤达祯  唐书恒  许浩  林文姬  张彪 《地质学报》2008,82(10):1341-1349
在对鄂尔多斯盆地东缘58套采自不同层位不同地域煤样显微组分测试和低温液氮比表面测试的基础上,从比表面积、吸附曲线形态、阶段孔径结构分布、阶段孔径比表面积贡献、FHH分形特征几个方面刻画了煤储层微孔隙特征。同时,就“孔比表面积—孔隙结构—煤物质组成与化学结构”这一因果链,分析了鄂尔多斯盆地东缘煤微孔隙特征与煤变质程度、煤岩显微组分以及矿物组分与类型的关系。研究发现,Ro在0.60%~1.91%范围内,比表面积及FHH分形分维数先明显降低,Ro至1.3%后又略有回升,同时吸附回线“滞后环”及分形尺度对应的压力范围明显减小,孔径3~4 nm“墨水瓶”型孔明显减少乃至消失,并成为比表面积减少的主要贡献者。在相似煤级条件下,惰质组分较镜质组分有更多的比表面积贡献。粘土矿物组分含量>10%时,孔径3~4 nm“墨水瓶”型孔对比表面贡献明显,且随煤级增高影响作用相对加大。  相似文献   
223.
程彦博  毛景文 《地质学报》2008,82(11):1478-1493
在云南个旧地区发育大量与成矿时空密切相关的侵入岩。个旧东区的老厂-卡房花岗质岩体为一隐伏的花岗岩体,侵入于三叠纪个旧组灰岩和碳酸盐地层中,岩性主要为中细粒黑云母花岗岩,是个旧地区与成矿关系最为密切的花岗岩体之一。岩石的ACNK值大多在1.0以上,属于高钾钙碱性系列岩石;U、Th含量较高,应归属于HHP花岗岩;岩石类型属于S型花岗岩,但经历了高度的分异和演化;n(Rb)/n(Sn)- n(Rb)/n(Ba)与n(CaO)/n(Na2O)-n(Al2O3)/n(TiO2)图解均暗示岩石的源区性质为由粘土岩所派生的岩浆。锆石LA-ICP-MS定年结果表明,老厂-卡房岩体形成于85±0.85Ma,相当于晚白垩世。根据区域地质和花岗岩的地球化学特征,暗示个旧地区燕山晚期处于伸展构造背景。  相似文献   
224.
江西省德兴铜矿矿区重金属元素的环境效应   总被引:6,自引:0,他引:6  
初娜  赵元艺  张光弟  杨慧 《地质学报》2008,82(4):562-576
本文系统研究了德兴铜矿排石场和尾砂库的环境问题,以环境介质(水土植物)中重金属元素含量为研究对象,论述矿区重金属的环境效应。研究结果表明祝家村低品位矿石堆浸场淋滤产生的酸性废水是造成大坞河流域重金属污染的主要来源。大坞河上游水体中Cu元素含量高达14506μg/L,是国家Ⅲ级水标准的14倍之多,Zn元素含量高达2938μg/L,是国家Ⅲ级水标准的2.9倍,同时pH值在3~4范围内;到中下游水体中Cu元素含量减小到几千到几百μg/L,水质有所改善。大坞河沿岸上游和中游土壤重金属含量受河水影响,随着与河岸距离的增加而减小。同时水稻中Pb元素含量是国家粮食标准的2倍。推测4#尾砂库尾砂表层氧化带深度大于80cm;而1#尾砂库库内尾砂中氧化带估计在0~25cm处。推测两个尾砂库产酸能力小于酸中和能力,故坝底水中pH值在7左右,对周围水体影响较小。与4#尾砂库距离近的石墩头村稻田表层土壤中Cu、Mo元素含量较高,远离尾砂库土壤中重金属含量降低。同时4#尾砂库周围土壤中Cd、Pb、Cu元素的吸附态、碳酸盐态比例在20%左右,因而在酸性环境下较容易被植物吸收。1#尾砂库矿建村种植的小白菜中Pb元素含量超过国家蔬菜标准的4倍,Cu、Pb、Zn元素含量严重超过背景值。  相似文献   
225.
Two sets of cooling experiments were run at atmospheric conditions for two anhydrous starting latitic and trachytic melts: 1) five cooling rates (25, 12.5, 3, 0.5, and 0.125 °C/min) between 1300° and 800 °C, and 2) a 0.5 °C/min cooling rate from 1300 °C with quench temperatures at 1200°, 1100°, 1000° and 900 °C. Trachytic run-products are invariably glassy. Nucleation is also suppressed in the latitic run-products at the three highest cooling rates. Conversely, in the 0.5 and 0.125 °C/min runs, latites have a crystal content of  90 vol.%. The phases are: plagioclase, clinopyroxene, glass and iron-bearing oxide (in order of abundance). The variable quench temperatures, investigated by coupling experiments with Pt wire and Pt capsule sample containers in set 2, again did not produce crystallization of trachyte, whereas latitic samples are characterized by  10 vol.% of oxides, pyroxenes and plagioclase (in order of appearance), at temperature < 1000 °C. Effects of (preferential) heterogeneous nucleation on sample holders, of superheating degree, and chemical species loss during cooling are absent for both melt compositions. The difference of solidification paths between these two silicate melts can be ascribed only to their small chemical differences. In comparison with calculated equilibrium conditions all the experimental latitic and trachytic run-products revealed strong kinetic effects, interpretable in the light of the nucleation theory. The glass-forming ability (GFA) of trachyte is higher, whereas their critical cooling rate (Rc) is lower (< 0.125 °C/min), in comparison to latitic melts (Rc > 0.5 °C/min). The experimental results carried out in this study can be applied to lava flows and domes; trachytic lavas are able to flow for longer period with respect to latitic ones in a metastable condition. Glass-rich terrestrial lavas, i.e. obsidians, can be the result of sluggish nucleation kinetics due to the relative high polymerisation of evolved silicate melts.  相似文献   
226.
MODFLOW is a groundwater modeling program. It can be compiled and remedied according to the practical applications. Because of its structure and fixed data format, MODFLOW can be integrated with Geographic Information Systems (GIS) technology for water resource management. The North China Plain (NCP), which is the politic, economic and cultural center of China, is facing with water resources shortage and water pollution. Groundwater is the main water resource for industrial, agricultural and domestic usage. It is necessary to evaluate the groundwater resources of the NCP as an entire aquifer system. With the development of computer and internet information technology it is also necessary to integrate the groundwater model with the GIS technology. Because the geological and hydrogeological data in the NCP was mainly in MAPGIS format, the powerful function of GIS of disposing of and analyzing spatial data and computer languages such as Visual C and Visual Basic were used to define the relationship between the original data and model data. After analyzing the geological and hydrogeological conditions of the NCP, the groundwater flow numerical simulation modeling was constructed with MODFLOW. On the basis of GIS, a dynamic evaluation system for groundwater resources under the internet circumstance was completed. During the process of constructing the groundwater model, a water budget was analyzed, which showed a negative budget in the NCP. The simulation period was from 1 January 2002 to 31 December 2003. During this period, the total recharge of the groundwater system was 49,374 × 10m3 and the total discharge was 56,530 × 10m3 the budget deficit was −7,156 × 10m3. In this integrated system, the original data including graphs and attribution data could be stored in the database. When the process of evaluating and predicting groundwater flow was started, these data were transformed into files that the core program of MODFLOW could read. The calculated water level and drawdown could be displayed and reviewed online.  相似文献   
227.
228.
A. Wendy Russell 《Geoforum》2008,39(1):213-222
In this paper, I argue that genetically modified organisms (GMOs) have inherent potential to contribute to socially and environmentally sustainable agriculture by virtue of their ‘biological embeddedness’. Their actual ‘performance’ and how this contributes to sustainability depends on the ‘mutual shaping’ of technology and context. While much attention has been given to the design context of GMOs, this paper considers the influence of the application context and of users. A case study investigating the use of insect-resistant and herbicide-tolerant GM cotton in the cotton-growing region of New South Wales in Australia is presented. The study was based on focus groups with farmers and other stakeholders in a cotton-growing community. It demonstrated a range of direct and indirect effects of GM cotton use, both positive and negative for sustainability, and the ways in which these effects were influenced by the local social context. The influences of the biotechnology industry context, in limiting the contributions that gene technologies can make to sustainability, were also considered, and remedies suggested. I argue that the polarity of the GM debate is hindering progress on these issues, and that a more balanced approach to our analysis of GMOs is necessary in order to fully understand, and to influence, their role in the future of rural spaces.  相似文献   
229.
Networking between companies and other regional key actors has grown into a widespread instrument for economic development since the 1990s. Participatory networks have formed the concept for many activities of Local Agenda 21. Simultaneously, economic geography has focused on network theories to explain innovation in and the economic success of regions.This article focuses on the reasons why individual actors participate in environmentally oriented information networks. The questions approached are: Does the concept of learning within networks influence a firm’s development? How do the participants interact with each other? What effects do the networks have on their environment (arenas)?The changing arenas of a firm are analysed with regard to environmental concerns. These changes need to be anticipated for reliable strategies. To gain information and knowledge about current behaviour and activities, the functions of networks as learning platforms are discussed. Drawing upon arguments from different network theories, the motivations of participating in a network are threefold: actor and firm oriented, network internal (inter-firm), and network external. From these, a generic target cube of network motivations and actions is set up.The concept is reviewed by examining 12 ‘regional environmental information-oriented corporation networks’ (RUN) in the Greater Munich Area. The empirical material reveals that this type of network does not provide a guarantee for significant improvements in a firm’s environmental behaviour. However, participants learn about best practices while pursuing explicit or implicit aims as to influence their arenas.  相似文献   
230.
One of Piers Blaikie’s most important contributions to the development of political ecology is his critique of land and resource conservation policy in the global South. In this paper I trace the development of Blaikie’s ideas about the policy relevance of political ecology, focusing particularly on the challenges posed by the introduction of poststructural social theory into the field. I begin by revisiting Blaikie’s earlier critiques of environment and development policy. This will provide the departure point to explore how his thinking on the relationship of theory and policy and of academic and development practices has evolved in subsequent writings. I have invented two personas, “early Blaikie” and “late Blaikie”, to facilitate this task. Second, I want to probe some of the challenges that late Blaikie presents for doing political ecology research, to some extent by pitting early Blaikie against late Blaikie and letting them hash it out. Third, I turn to my own and others’ research and consultation experiences as a way to examine the possibilities for reconciling theoretically driven critiques with policy relevant research.  相似文献   
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