热磁技术及其在勘查地球化学中的应用前景

通过热磁技术特性分析,指出热磁组分并不完全等同于铁锰氧化物,同时从确定矿床有效指示元素组合、判断次生异常性质及在厚覆盖区寻找隐伏矿等几方面展望了热磁技术在勘查地球化学中的应用前景,介绍了热磁技术实验的初步成果。     

四川蒲江-雅安地区自流井组地层特征及沉积相

在雅安沙坪自流井组实测地层剖面的基础上,讨论了四川蒲江-雅安地区自流井组的岩石地层、接触关系及岩性岩相的横向变化规律。认为自流井组主要为一套湖泊-湖泊三角洲沉积,组成一个完整的长期基准面旋回层序,在自流井组中建立了一个双壳类即Pseudocardiniaovalis-Pseudocardinia cf.submagna组合,根据化石组合及地层关系将自流井组的年代地层归属于下侏罗统。     

Seeding nature, ceding culture: Redefining the boundaries of the marine commons through spatial management and GIS

The oceans are not only being transformed through privatization as management moves towards market mechanisms, the oceans are also being “zoned”, with zoning increasingly proposed as the ideal conduit for weighting different uses of the ocean. This is concomitant with a move towards ecosystem-based management that also partakes in a policy environment imbued with the commodification of nature, in which environmental services are ranked and valued according to neoliberal percepts. Crucial to these projects are the utilization of GIS technologies. This paper considers these zones of preservation and sites of conflict through an ethnographic case study of the scallop fisheries of New England, examining conflicts between harvesters, different projects to map the fishery, and ongoing efforts to reseed scallop beds. The paper explores how participants themselves articulate the changing practices of fishing and farming, redefining boundaries of nature and culture. While reseeding projects, for example, arguably participate in the market logic of neoliberalism, at the same time they may resist and redefine the terms, as communities see themselves sowing the seeds of their own sustainability and changing the terms of what counts, literally, as nature.     

The impact of “community” on fisheries management in the US Northeast

The discourse of fisheries science and management displaces community and culture from the essential economic dynamic of fisheries. The goal of this dominant discourse is to enclose fisheries, to constitute them as within the singular and hegemonic economy of capitalism. Alternative economies, such as those based on the presence of community, are always seen as either existing before or beyond the dominant economic formation. The category of community is, nevertheless, being incorporated into contemporary fisheries science and management where it has the potential to disrupt the ontological foundations of the current management regime. To avoid disruption, community is situated such that it is the domain of anthropology while the essential economic dynamic of fisheries remains the purview of fisheries bioeconomics. Community can be identified, documented, and analyzed but always only as a site of economic impact and never as a constituent of the economic itself. Curiously, this disciplining of community has a literal geographic dimension: the discursive domain of bioeconomics corresponds to the spatial domain of fisheries resources themselves while that of fisheries social science/anthropology corresponds to the terrestrial locations where fishers reside. Fishing ports become the place of community while the actual common property resource remains the site where the essential economic dynamic reigns uncompromised.     

大姚六苴铜矿床小河-石门坎矿段地层地球化学

大姚六苴铜矿床是楚雄红色盆地中砂(页)岩型铜矿的典型代表.其中小河-石门坎矿段主要分布白垩系,矿体严格受地层控制.根据该矿段7个钻孔揭露的地质信息,总结了剖面上地层颜色的交替变化规律.通过对白垩系不同层位主量元素、微量元素地球化学特征的对比,阐述了浅色层、紫色层元素的变化特征,提出了具有矿化指示意义的元素组合为Cu-Hg-Ag-Sn-Zn-As-Sb-Mn,为深部找矿预测提供了重要依据.     

Geologically Constrained Fuzzy Mapping of Gold Mineralization Potential,Baguio District,Philippines

An application of the theory of fuzzy sets to the mapping of gold mineralization potential in the Baguio gold mining district of the Philippines is described. Proximity to geological features is translated into fuzzy membership functions based upon qualitative and quantitative knowledge of spatial associations between known gold occurrences and geological features in the area. Fuzzy sets of favorable distances to geological features and favorable lithologic formations are combined using fuzzy logic as the inference engine. The data capture, map operations, and spatial data analyses are carried out using a geographic information system. The fuzzy predictive maps delineate at least 68% of the known gold occurrences that are used to generate the model. The fuzzy predictive maps delineate at least 76% of the unknown gold occurrences that are not used to generate the model. The results are highly comparable with the results of previous stream-sediment geochemical survey in the area. The results demonstrate the usefulness of a geologically constrained fuzzy set approach to map mineral potential and to redirect surficial exploration work in the search for yet undiscovered gold mineralization in the mining district. The method described is applicable to other mining districts elsewhere.     

Cogeneticity of Tavidar volcanics: Evidence by mixing line calculation

The Tavidar volcanics belong to a trachybasalt-trachyandesite-rhyolite association. Distribution and behavior of major and trace elements and field relationships indicate that intermediate and acidic volcanics of the area are cogenetic, whereas the basaltic phase is younger. Cogeneticity also is confirmed by the mixing line calculation. In the present case, instead of two pole mixing, three pole mixing between end members andesite, quartztrachyte, and rhyolite has been considered. Results show that a perfect linearity in data exists between andesites and quartztrachyte and between quartztrachyte and rhyolites.     

Spatial statistics for urban analysis: A review of techniques with examples

Traditionally, urban analysis has been quick to adopt and benefit from developments in technology (e.g., microcomputer, GIS) and techniques (e.g., statistics, mathematical programming). This has not been the case, however, with newer methods of spatial analysis — in particular, spatial statistics. Only recently has this situation started to change. This paper documents the confluence of spatial statistics and urban analysis by first reviewing developments in spatial statistics, and then presenting examples of recent applications in urban analysis. The developments reviewed fall under the rubric of global and local forms of spatial analysis, and cover three major technical issues: spatial association, spatial heterogeneity and the modifiable areal unit problem. The examples highlight the relevance and usefulness of the techniques reviewed for urban transportation and land-use applications. The paper concludes with conjectures concerning future developments at the intersection of spatial statistics and urban analysis.     

柴窝堡盆地石油地质特征与油气勘探前景

柴窝堡盆地具前震旦系结晶基底，二叠系至第四系组成盆地盖层。从石油地质特征分析，柴窝堡盆地具一定的成藏条件，主要烃源岩为上二叠统芦草沟组，储集层主要为芦草沟组砂岩或砂砾岩，上覆红雁池组－仓房沟群为良好的盖层，燕山运动和喜山运动为圈闭形成和定型期，大量排烃期是侏罗纪－白垩纪，油气生成、运移期匹配较好。本区发育3大套生储盖组合，从构造上分析芨芨槽子古隆起周围及雷家沟构造带深部的芦草沟组有利生油区，物性较好，为油气运移指向，是下一步勘探的有利目标。