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1.
In this paper, I analyze the connections made between women and water in a Rajasthani drinking water supply project as a significant part of drinking water’s commodification. For development policy makers, water progressing from something free to something valued by price is inevitable when moving economies toward modernity and development. My findings indicate that water is not commodified simply by charging money for it, but through a series of discourses and acts that link it to other “modern” objects and give it value. One of these objects is “women”. I argue that through women’s participation activities that link gender and modernity to new responsibilities and increased mobility for village women involving the clean water supply, a “traditional” Rajasthani woman becomes “modern”. Water, in parallel, becomes “new”, “improved” and worth paying for. Women and water resources are further connected through project staff’s efforts to promote latrines by targeting women as their primary users. The research shows that villagers applied their own meanings to latrines, some of which precluded women using them. This paper fills a gap in feminist political ecology, which often overlooks how gender is created through natural resource interventions, by concerning itself with how new meanings of “water” and “women” are mutually constructed through struggles over water use and its commodification. It contributes to critical development geography literatures by demonstrating that women’s participation approaches to natural resource development act as both constraints and opportunities for village constituents. It examines an under-explored area of gender and water research by tracing village-level struggles over meanings of latrines.  相似文献   

2.
B. L. Turner II 《Geoforum》2002,33(4):427-429
Reviews and observations about the status of the discipline of geography, no matter how positive, invariably raise programmatic concerns. These concerns have a long history that arise from geography's struggles to find an identity that embraces its many parts and yet are consistent with the logic by which the academy partitions knowledge. Pedagogy and research historically claimed by geography is currently being reinvented and relabeled under such headings as “integrated environmental science” and “spatial science”, and these developments have the potential to change the breadth of the “geographic imagination”. Several observations about dominant explanatory perspectives and substantive domains of geographic enquiry are also provided.  相似文献   

3.
Although “barkinite” has long been studied by many geologists, its geochemical characteristics and environment of deposition are still not known in detail. In order to study the petrography and geochemical characteristics of “barkinite”, coal samples from two Permian coal seams were taken from the Dahe mine, Guizhou Province. The samples were separated into maceral fractions, and then analyzed by microscopical, isotopic, Rock-Eval, and geochemical methods. The microscopical results indicate that “barkinite” occurs as four main types. According to their relationship to other maceral groups, “barkinite” is ostensibly formed under variably dry–wet or oxidizing–reducing conditions. The extract yield, isotope data and Rock-Eval values of “barkinite” are different from other macerals. Microscopical and geochemical results indicate that “barkinite” forms part of the liptinite group.  相似文献   

4.
In the Witwatersrand approximately 40% of the gold is intimately associated with so-called “carbon” in “carbon seam reefs”, which occur in over a dozen paleoplacers, many of them concentrated at two stratigraphic levels in the 7000-m-thick succession of Archean siliciclastic sedimentary rocks. This is reduced carbon, present as kerogen admixed in various proportions with derivative (now solid) bitumen(s). Oil generation and migration were active geological processes during Early Earth history. Numerous possible source rocks for oil generation, including the carbon seams themselves, occur within the Witwatersrand basin. In the Witwatersrand ore, oil-bearing fluid inclusions are also present, derived like the bitumen, by thermal maturation of the kerogen. The presence of kerogen and bitumen in the Witwatersrand sedimentary rocks, together with a wealth of observations on the spatial distribution of the carbon seams confirm that the carbon originated in situ from living organisms in microbial mat cover, as opposed to flowing in from elsewhere as liquid hydrocarbons as some researchers have suggested. Paleochannels, which truncated auriferous carbon seams early in the depositional history, are of widespread occurrence, and micro-synsedimentary faults offset carbon seams. The carbon seams are thus indigenous biogenic markers that grew contemporaneously with placer development. The various features highlighting the nature and spatial distribution of Witwatersrand carbon seams provide a classic case where field evidence trumps laboratory data in the reconstruction of geological processes.  相似文献   

5.
Leping coal is known for its high content of “barkinite”, which is a unique liptinite maceral apparently found only in the Late Permian coals of South China. “Barkinite” has previously identified as suberinite, but on the basis of further investigations, most coal petrologists conclude that “barkinite” is not suberinite, but a distinct maceral. The term “barkinite” was introduced by (State Bureau of Technical Supervision of the People's Republic of China, 1991, GB 12937-91 (in Chinese)), but it has not been recognized by ICCP and has not been accepted internationally.In this paper, elemental analyses (EA), pyrolysis-gas chromatography, Rock-Eval pyrolysis and optical techniques were used to study the optical features and the hydrocarbon-generating model of “barkinite”. The results show that “barkinite” with imbricate structure usually occurs in single or multiple layers or in a circular form, and no definite border exists between the cell walls and fillings, but there exist clear aperture among the cells.“Barkinite” is characterized by fluorescing in relatively high rank coals. At low maturity of 0.60–0.80%Ro, “barkinite” shows strong bright orange–yellow fluorescence, and the fluorescent colors of different cells are inhomogeneous in one sample. As vitrinite reflectance increases up to 0.90%Ro, “barkinite” also displays strong yellow or yellow–brown fluorescence; and most of “barkinite” lose fluorescence at the maturity of 1.20–1.30%Ro. However, most of suberinite types lose fluorescence at a vitrinite reflectance of 0.50% Ro, or at the stage of high volatile C bituminous coal. In particular, the cell walls of “barkinite” usually show red color, whereas the cell fillings show yellow color under transmitted light. This character is contrary to suberinite.“Barkinite” is also characterized by late generation of large amounts of liquid oil, which is different from the early generation of large amounts of liquid hydrocarbon. In addition, “barkinite” with high hydrocarbon generation potential, high elemental hydrogen, and low carbon content. The pyrolysis products of “barkinite” are dominated by aliphatic compounds, followed by low molecular-weight aromatic compounds (benzene, toluene, xylene and naphthalene), and a few isoprenoids. The pyrolysis hydrocarbons of “barkinite” are mostly composed of light oil (C6–C14) and wet gas (C2–C5), and that heavy oil (C15+) and methane (C1) are the minor hydrocarbon.In addition, suberinite is defined only as suberinized cell walls—it does not include the cell fillings, and the cell lumens were empty or filled by corpocollinites, which do not show any fluorescence. Whereas, “barkinite” not only includes the cell walls, but also includes the cell fillings, and the cell fillings show bright yellow fluorescence.Since the optical features and the hydrocarbon-generating model of “barkinite” are quite different from suberinite. We suggest that “barkinite” is a new type of maceral.  相似文献   

6.
The Kuroshima Knoll is about 26 km south of Ishigaki Island in the southern part of the Ryukyu Arc. The area is considered to be the source area of “The 1771 Yaeyama Earthquake Tsunami”, which was due to the submarine landslide caused by an earthquake. It has been cleared from some investigations using “Dolphin 3K” and “Shinkai 2000” that there are large-scale dead Calyptogena colonies, many gravels of fallen dolomite chimneys and carbonates on the top of the Knoll [Matsumoto, T., Uechi, C., Kimura, M., 1997; Machiyama, H., Matsumoto, T., Matsumoto, R., Hattori, M., Okano, M., Iwase, R., Tomaru, H., 2001b.]. Carbonates of Kuroshima Knoll have various shapes and macroscopic textures. These have been classified into 4 types; shell crust (pavement), chimney, burrow, and nodule. It is clear that all chimney and burrow carbonates are composed of dolomite, while shell curst and nodule are composed of calcite, sometimes both calcite and dolomite. These carbonates are considered to have been formed by cold seep, because they are characterized by the light carbon isotopic ratio (semi-biogenic) and the heavy oxygen isotopic ratio. This suggests that methane hydrate layers develop under this survey area and the water that has the heavy oxygen and the light carbon isotopic ratio is derived from the dissociation of methane hydrate.  相似文献   

7.
Jody Emel  Matthew T. Huber   《Geoforum》2008,39(3):1393-1407
Natural resource investment in the mining sector is often mediated through conflicts over rent distribution between corporate capital and landowner states. Recent rounds of neoliberal policy promoted by the World Bank have highlighted the need for landowner states to offer incentives in order to attract “high risk” capital investment. In Sub-Saharan Africa, in particular, countries have been pushed to offer attractive fiscal terms to capital, thereby lowering the proportion traditionally called rent. This paper examines how the concept of “risk” has been mobilized to legitimate such skewed distributional arrangements. While certain conceptions of social and ecological “risk” have been prevalent in political and social theoretic discourse on mining, such focus elides the overwhelming contemporary power of our notion of “neoliberal risk” – or the financial/market risks – in actually setting the distributional terms of mineral investment. We illustrate our argument by examining the nexus of World Bank mining policy promotion and Tanzanian policy in the late 1990s meant to attract foreign direct investment in gold production. In closing, we suggest that just as “risk” is used to legitimate attractive fiscal terms for investment, recent events highlight how skewed distribution of benefits may set into motion risks that corporate capital had not bargained for.  相似文献   

8.
A theory of two-dimensional geothermic problems is elaborated by the active temperature function at the vertical contact of two horizontally layered media. The approach offered before for oceanic ridges is extended to the case of continental margins and the upper part of a descending slab, i.e. “sink”, in island-arc areas. It is assumed that the plate motion in the oceanic area exists; in a descending area it is directed downward but remains zero on a continental side. Mathematically it symbolizes a “source—span—sink” thermal model. Numerical parameters are given for a theoretical thermal model of the heat-flow profile across the Kuril island arc, from the trench through Iturup Island, Sakhalin Island and the Tatarian Trough.  相似文献   

9.
In the Mt. Franks area of the Willyama Complex, microfabric evidence suggests that the alteration of andalusite to sillimanite has taken place by a process similar to that suggested by Carmichael (1969). Andalusite is pre- to syn-S2 in age. Alteration to “sericite” has resulted in the formation of “sericite” laths, some of which are crenulated about S2, and some which are syn- and post-S2. “Fibrolite” occurs in these andalusite—“sericite” aggregates within the sillimanite zone and is wholly embedded in “sericite”. “Fibrolite” is pre- to syn-S2 in age. This evidence is interpreted as suggesting that the formation of sillimanite from andalusite took place via a “sericite” phase.Further microfabric observations are interpreted to imply constant volume for the reaction aluminosilicate → “sericite”. This suggests a situation in which Al3+ is relatively mobile but Al4+ is relatively immobile. This suggestion differs from Carmichael's (1969) idea of Al3+ immobility.  相似文献   

10.
John Harrison   《Geoforum》2006,37(6):932-943
The “region” and “regional change” have been elusive ideas within political and economic geography, and in essence require a greater understanding of their dynamic characteristics. Trailing in the backwaters of the devolution to the Celtic nations of Britain, the contemporary era of New Labour’s political-economic ideology, manifest through “third-way” governance in England places the region and its functional capacity into the heart of geographical inquiry. Drawing upon a new regionalist epistemology, this paper seeks to recover a sense of (regional) political economy through a critical investigation of the development and formulation of Blair’s “New Regional Policy” (NRP). I address how New Labour has attempted to marry economic regionalisation on the one hand, and democratic regionalism on the other. This paper specifically questions the wisdom of such a marriage of politically distinct ideologies through a critical investigation of the underlying contradictions of their strategy from both a theoretical and empirical standpoint. Demonstrated both in the North East “no” vote in 2004, and in the post-mortem undertaken by the ODPM Select Committee in 2005, the paper illustrates how a loss of political drive gradually undermined the capacity of devolution to deliver in England. Finally, I argue that through the lens of the NRP we can speculate on some of the wider issues and implications for the study of regional governance.  相似文献   

11.
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12.
The Reguibat Shield comprises a western “Archaean terrane” and eastern “Eburnean terrane” juxtaposed during the early Palaeoproterozoic Eburnean Orogeny. Metasedimentary rocks of probable Palaeoproterozoic age are preserved as flat-lying klippen (Kediat Ijil and Guelb Zednes) and steep imbricate zones (El Mahaoudat range and Sfariat Belt). These are interpreted to record a phase of thrust tectonics that emplaced a continental margin succession onto a composite Archaean foreland prior to ca. 2.06 Ga sinistral transcurrent deformation. Together, these events reflect partitioned Eburnean transpression.  相似文献   

13.
Onshore–offshore seismic refraction profiling allows for the determination of crustal and mantle structures in the transition between continental and oceanic environments. Islands and narrow landmasses have the unique geometry of allowing for double-sided onshore–offshore experiments that favor the construction of composite “super-gathers” using the acquisition of onshore–offshore and ocean-bottom seismometer receiver gathers, land explosion shot gathers, and near-vertical incidence multichannel seismic (MCS) profiling. A number of sites at plate boundaries are amenable to the application of double-sided onshore–offshore imaging, including the Indo-Australian/Pacific transform boundary on South Island, New Zealand. By comparing the ratio of island width to mantle refraction (Pn) “maximum” crossover distance, using nondimensional distances, we provide an indicator of raypath “coverage” for crustal illumination. Islands or narrow land masses whose widths are less than twice their maximum crossover distance are candidates for double-sided onshore–offshore experiments. The SIGHT (South Island GeopHysical invesTigation) experiment in New Zealand is located where the width of South Island is sufficiently narrow with respect to its crustal thickness that a double-sided onshore–offshore experiment allows for complete crustal imaging of the associated plate boundary.  相似文献   

14.
In order to understand the origin of long-lived loci of volcanism (sometimes called “hot spots”) and their possible role in global tectonic processes, it is essential to know their deep structure. Even though some work has been done on the crustal, upper-mantle, and deep-mantle structure under some of these “hot spots”, the picture is far from clear. In an attempt to study the structure under the Yellowstone National Park U.S.A., which is considered to be such a “hot spot”, we recorded teleseisms using 26 telemetered seismic stations and three groups of portable stations. The network was operated within a 150 km radius centered on the Yellowstone caldera, the major, Quaternary volcanic feature of the Yellowstone region. Teleseismic delays of about 1.5 sec are found inside the caldera, and the delays remain high over a 100 km wide area around the caldera. The spatial distribution and magnitude of the delays indicate the presence of a large body of low-velocity material with horizontal dimensions corresponding approximately to the caldera size (40 km × 80 km) near the surface and extending to a depth of 200–250 km under the caldera. Using ray-tracing and inversion techniques, it is estimated that the compressional velocity inside the anomalous body is lower than in the surrounding rock by about 15% in the upper crust and by 5% in the lower crust and upper mantle. It is postulated that the body is partly composed of molten rock with a high degree of partial melting at shallow depths and is responsible for the observed Yellowstone volcanism. The large size of the partially molten body, taken together with its location at the head of a 350 km zone of volcanic propagation along the axis of the Snake River Plain, indicates that the volcanism associated with Yellowstone has its origin below the lithosphere and is relatively stationary with respect to plate motion. Using our techniques, we are unable to detect any measurable velocity contrast in the mantle beneath the low-velocity body, and, hence, we are unable to determine whether the Yellowstone melting anomaly is associated with a deep heat source or with any deep phenomenon such as a convection plume, chemical plume, or gravitational anchor.  相似文献   

15.
Digging into Google Earth: An analysis of “Crisis in Darfur”   总被引：1，自引：0，他引：1  
Lisa Parks   《Geoforum》2009,40(4):535-545
Google publicists have suggested the Crisis in Darfur is an example of the Google Earth software’s “success at tangibly impacting what is happening on the ground.” Yet whether or not Google Earth’s interface, along with a medley of other media representations of the conflict, have impacted events on the ground or led to coherent policies of humanitarian intervention remains open to debate. This article draws upon critical approaches from media studies—namely discourse analysis—to analyze several aspects of the Google Earth/USHMM Crisis in Darfur project. While this project was no doubt developed with the noble intention of generating international awareness about widespread violence that has recently occurred in the Darfur region, it is important to evaluate how representations of global conflicts are changing with uses of new information technologies and whether such representations can actually achieve their desired impacts or effects. The article begins with a discussion of the Crisis in Darfur project’s history, proceeds to analyze some of the press coverage of the project and then moves to a critique of the layer using four categories of analysis: (1) the shifting role of satellite image; (2) the temporality of the interface; (3) the practice of conflict branding; and (4) the practice of “information intervention.” Throughout the article, I explore how the presentation of Darfur-related materials through Google Earth reproduces problematic Western tropes of African tragedy and misses an opportunity to generate public literacy around satellite images. I also consider how humanitarianism is intertwined with digital and disaster capitalism, and suggest that this instance of “information intervention” makes patently clear that high visual capital alone cannot resolve global conflicts.  相似文献   

16.
Radiocaesium (137Cs) dispersion and Cs+ fixation were studied in the sediments collected from the lagoon systems of “Ria de Aveiro”. The Cs+ sorption was tested for the fine mica grains and for the < 2 μm clay fractions extracted from silty clays. The Cs+ exchange is found strongly onto mica-rich fractions than smectite-rich fractions. The distribution coefficient increases if the silty material is constituted by rich-mica clay fractions or if the non-clay minerals are removed from the silty-clay material. The samples studied behave as multisite ion exchange, where Cs+ engages in ion-exchange reactions with hydrated cations on planar sites on expansible layer silicates. Higher concentrations of the 137Cs were found associated with mica-rich silty clays. The 137Cs ranges from 3.2 to 3.9 Bq kg− 1 in the < 38 μm fractions and from 2.9 to 3.3 Bq kg− 1 in the < 64 μm fractions.  相似文献   

17.
In the Alberta Basin there is a significant difference in the content of Fe between formation waters from drillstem tests and formation waters from producing wells. This was demonstrated using a data set comprising 525 formation waters from drillstem tests and 107 formation waters from producing wells. Both a cross-plot of Mn and Fe in the two sets of formation waters and box plots of the same data sets showed that formation waters from producing wells have dominantly Fe>Mn, compared with those from drillstem tests which are characterized by Mn>Fe. Suspecting that “rust” contamination from well casing and ancillary equipment was the cause, the pH values of the samples were compared to see if the two data sets also differed in pH. It was demonstrated that not only are formation waters from drillstem tests less acidic than those from producing wells, but there is a systematic statistical trend of increasing acidity with age of the strata (temperature, depth, and increased amounts of the acid gases — H2S and CO2). The difference between the pH of formation waters from drillstem tests and producing wells is attributed to the partial scrubbing of the acid gases from the fluids produced during the drillstem test; this results in less acidic formation waters. Vanadium may also be enhanced in formation waters from producing wells. This note reports these differences and cautions too much reliance on values for Fe in waters from producing wells.  相似文献   

18.
Macromolecular organic material, called “polymeric acids”, has been isolated from Black Trona Water by exhaustive dialysis and characterized as the sodium salt in 0.10 M sodium carbonate, pH 10, by several physico-chemical methods. Analysis by gel filtration chromatography on Sepharose-CL 6B indicates that the “polymeric acids” are polydisperse and composed of species of relatively high molecular weight ( 4 × 105, using proteins as standards). With this method, the range of molecular weights appears to be rather narrow. If “polymeric acids” are transferred from sodium carbonate, pH 10, into distilled water, selfassociation occurs and all species elute in the void volume. The weight-average molecular weight determined in 0.10 M sodium carbonate, pH 10, by the light scattering method is 1.7 × 105. Sedimentation velocity analysis at 20°C with the analytical ultracentrifuge gives a value for S20,w of 5.4 and the shape of the Schlieren patterns suggest a polydisperse sample with a relatively narrow range of sizes. Analysis of the molecular weight distribution by a sedimentation equilibrium method indicates that the range of molecular weights is 8 × 104 to 2.1 × 105. The partial specific volume ( ) of “polymeric acids” is 0.874 ml/g. Viscosity measurements yield a value for [η] of 2.5 ml/g, which indicates that the “polymeric acids” are compact (spherical or ellipsoidal) in shape.  相似文献   

19.
The offsets on the ocean floor, usually called “transform-faults” are not shear faults common in solid Hookian rocks, but reflect the viscous Newtonian properties of laminar flow at the time when the upwelling magma along the spreading center was still in a liquid state. During spreading this liquid is carried away with the walls of the spreading center. This movement creates a pattern of stream lines in the liquid which run parallel to the direction of spreading. “Transform faults” are initiated along zones where a larger rate of shear disturbs the process of solidification. Consequently the strength of the basalt after solidification will be impaired along these zones. These weak zones will fracture under the thermo-elastic stresses during the final stage of cooling.The history of the term “transform fault” is discussed and the name “spreading offset” is proposed.  相似文献   

20.
This is a critical assessment of the paper by Oszczypko et al. (2004: Cretaceous Research 25, 89–113), in which they tried to prove a mid-Cretaceous age for the Szlachtowa (“black flysch”) and Opaleniec Formations, in the Pieniny Klippen Belt, West Carpathians, both of which had previously been shown to be of Jurassic age. We argue that the mid-Cretaceous age assignment is a misinterpretation, primarily resulting from their field samples having been collected from some Cretaceous lithostratigraphic units, tectonically associated with the Jurassic formations, and/or from tectonic contact-breccias involving Jurassic and Cretaceous strata. In addition, we suggest that they have overlooked a number of significant palaeontological papers, published since 1962, which record the presence of in situ ammonites, aptychi, belemnites, thin-shelled bivalves (Bositra), gryphaeids, foraminifera, and ostracod assemblages, all indicating a Jurassic (mainly Aalenian), and not a Cretaceous, age for the Szlachtowa Formation, and also the in situ Jurassic (Bajocian) ammonites and thin-shelled bivalves (Bositra), Bositra-microfacies, and age-diagnostic foraminiferal assemblages of the Opaleniec Formation.Our presentation here of recently published dinocyst data from well-preserved assemblages further supports the Jurassic ages for the Szlachtowa (“black flysch”) and Opaleniec Formations.  相似文献   

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