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331.
G. Chiodini R. Cioni A. Frullani M. Guidi L. Marini F. Prati B. Raco 《Bulletin of Volcanology》1996,58(5):380-392
Two geochemical surveys carried out in March 1991 and September 1992 revealed the existence of a hydrothermal system in the
southern portion of Montserrat Island, below Soufrière Hills Volcano. This conclusion is supported by the presence of: (a)
the thermal springs of Plymouth which are fed by deep Na–Cl waters (Cl concentration ∼25 000 mg/kg, temperature ca. 250 °C)
mixed with shallow steam-heated waters; (b) the four fumarolic fields of Galway's Soufrière, Gages Upper Soufrière, Gages
Lower Soufrière, and Tar River Soufrière, where acid to neutral, steam-heated waters are present together with several fumarolic
vents, discharging vapors formed through boiling of hydrothermal aqueous solutions. Involvement of magmatic fluids in the
recharge of the hydrothermal aquifers is suggested by: (a) the high 3He/4He ratios of fumarolic fluids, i.e., 8.2 RA at Galway's Soufrière and 5.9 RA at Gages Lower Soufrière; (b) the δD and δ18O values of Na–Cl thermal springs and steam condensates, indicating the involvement of arc-type magmatic water in the formation
of deep geothermal liquids; and (c) the CH4/CO2 ratios of fumarolic fluids, which are lower than expected for equilibrium with the FeO–FeO1.5 hydrothermal rock buffer, but being shifted towards the SO2–H2S magmatic gas buffer.
Received: 26 March 1996 / Accepted: 19 July 1996 相似文献
332.
民间叙事是指生活于社会底层的老百姓的口头叙述活动 ,主要指他们的艺术叙事。口头性是其基本特征 ,与此相关则有易变、易散失、往往无主名、在流传中发生增删而形成地域性和历史性异文、形式生动活泼、内容反映民众心理、民众思想和趣味、真实反映与自由想象相混杂 ,以及与主流文化既矛盾又统一等特点。民间叙事首先大量地存在于民间文学作品中 ,其次是寄居在文人叙事的文本中。文人的介入使民间叙事经历了一个文本化的过程 ,使民间叙事渐渐从活态的口化之物固化为书面文字。而官方的介入则进一步使某些文本变成了经典。文本 ,包括被经典化了的文本 ,又可以成为民间叙事的新源头 ,成为新的民间叙事的依据 ,即所谓“反哺”。 相似文献
333.
1 MathematicModelofTidalVibrationSupposethat 3semi -axesofaellipsoidarea ,bandc (a >b >c) ,latitudeisθ ,longitudeisψ(changingfrom 0°to 90°) , 相似文献
334.
Cold water in the deep Pacific can be drawn up to the surface (or west warm water drifts eastwards) because strong tide increases the mixing of seawater both in vertical and horizontal. In this way greenhouse effect is decreased or in-creased by means of absorbing (or releasing) CO2. Therefore, La Nina cold event (or El Nino warm event) may occur, which is caused by wanning - up or cooling - down air above the ocean. Volcanic action at sea bottom is also controlled by strong tide. 相似文献
335.
《The Professional geographer》1987,39(3):363-386
Book Reviewed in this article: Hillslope Processes. Binghamton Symposia in Geomorphology International Series: 16. Athol D. Abrahams , ed. The Atlas of Central America and the Caribbean. The Diagram Group . The Cultural Atlas of Islam. Isma'il R. al Faruqi and Lois Lamaya'al Faruqi . Atlas of Israel Contemporary Africa: Development, Culture and the State. Morag Bell . Fundamentals of Physical Geography. David Briggs and Peter Smithson . The Bicentennial Census: New Directions for Methodology in 1990. Constance F. Citro and Michael L. Cohen , eds . World Patterns of Modern Urban Change: Essays in Honor of Chauncy D. Harris. Michael P. Conzen , ed . New Directions for Agriculture and Agricultural Research: Neglected Dimensions and Emerging Alternatives. Kenneth A. Dahlberg , ed . Water Resources Atlas of Florida. E.A. Fernald and D.J. Patton , eds . Landscape Ecology. R.T.T. Forman and M. Godron . The Myth of the North American City: Continentalism Challenged. Michael Goldberg and John Mercer . The Permafrost Environment. Stuart A. Harris . Climate and Circulation of the Tropics. Stefan Hastenrath . The Island of South Georgia. Robert Headland . The Making of Urban Europe, 1000-1950. Paul M. Hohenberg and Lynn Hollen Lees . Bombay in Transition: The Growth and Social Ecology of a Colonial City, 1889–1980. Meera Kosambi . Plant Closings; Public or Private Choices? Richard B. McKenzie , ed . Malaysia: Tradition, Modernity and Islam. R.S. Milne and Diane K. Mauzy . Technology on the Frontier: Mining in Old Ontario. Dianne Newell . The Maritime Political Boundaries of the World. J.R.V. Prescott . Tall Office Buildings in the United States. James W. Pygman and Richard Kateley (Real Estate Research Corporation). Technology, Regions, and Policy. John Rees , ed . The United States and the Regional Organization of Asia and the Pacific: 1965-1985. W.W. Rostow . Renewable Energy: Progress, Prospects. Stephen W. Sawyer Wisconsin Foundations. Gwen Schultz . Dwelling, Place and Environment: Towards a Phenomenology of Person and World. David Seamon and Robert Mugerauer , eds . Power and Place: Canadian Urban Development in the North American Context. Gilbert A. Stelter and Alan F.J. Artibise , eds . Small Firms in Regional Economic Development: Britain, Ireland and the United States. D. J. Storey , ed . Mathematical Methods in Human Geography and Planning. A. G. Wilson and R. J. Bennett . El Niño North: Niño Effects on the Eastern Subarctic Pacific Ocean. W. S. Wooster and D. L. Fluharty , eds . The Soviet Iron and Steel Industry. Craig ZumBrunnen and Jeffrey Osleeb . 相似文献
336.
In this paper, we prove that the elliptical solutions and collision ejection solutions with the Eulerian collinear configuration
for planar 3-body problems are the variational minimizers of the Lagrangian action restricted on a suitable loop space. 相似文献
337.
边缘撕裂--一种致裂致震机制 总被引:1,自引:1,他引:0
明确提出两个板块或地块之间相互作用(主要是错动)中存在一种致裂致震机制-边缘撕裂,并以中国云南境内的红河断裂和美国加州的圣安德列斯两侧地块的边缘撕裂现象为例作了具体阐述。 相似文献
338.
This paper reports on the detection of a satellite around the principal nucleus of comet Hale-Bopp. As shown elsewhere, a
successful morphological model for the comet's dust coma necessitates the postulation of overlapping jet activity from a comet
pair. The satellite has been detected digitally on images taken with the Hubble Space Telescope's Wide Field Planetary Camera
2 in the planetary mode on five days in May–October 1996. An average satellite-to-primary signal ratio is 0.21 ± 0.03, which
implies that the satellite is ∼30 km in diameter, assuming the main nucleus is ∼70 km across. To avoid collision, the separation
distance must exceed 50–60 km at all times. The satellite's projected distances on the images vary from 160 to 210 km, or
0.06 to 0.10 arcsec. The satellite was not detected in October 1995, presumably because of its subpixel separation from the
primary. The radius of the gravitational sphere of action of the principal nucleus 70 km in diameter is 370–540 km at perihelion,
increasing linearly with the Sun's distance: the satellite appears to be in a fairly stable orbit. Its orbital period at ∼180
km is expected to be ∼2–3 days, much shorter than the intervals between the HST observations. If the main nucleus should be
no more than 42 km across, Weaver et al.'s upper limit, the satellite's orbit could become unstable, with the object drifting
away from the main nucleus after perihelion. Potentially relevant ground-based detections of close companions are reported.
Efforts to determine the satellite's orbit and the total mass of the system will get under way in the near future.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
339.
Effective action taken against climate change must find ways to unite scientific and practice-based knowledges associated with the various stakeholders who see themselves as invested in the global delivery of climate governance. Political decision-makers, climate scientists and practitioners approach this challenge from what are often radically different perspectives and experiences. While considerable work has been done to develop the idea of ‘co-production’ in the development of climate action outputs, questions remain over how to best unite the contrasting epistemological traditions and norms associated with different stakeholders. Drawing on the existing literatures on climate action co-production and from translational perspectives on the science-policy interface, in this paper we develop the concept of ‘boundary agency’. Defining this as the agency ‘possessed’ when willing and able to translate between different epistemological communities invested in a similar policy and governance challenge such as climate change, we offer it as a useful means to reflect on participants’ understanding of the ‘co’ in co-production. This is in contrast to the more established (often academic-led) focus on what it is that is being produced by co-production processes. We draw from two complementary empirical studies, which explicitly encouraged i) engagement and ii) reflection on cross-boundary co-production between climate action stakeholders from different backgrounds. Reflecting on the two studies, we discuss the benefits of (and barriers to) encouraging more active and sustained engagement between climate action stakeholders so as to try to actively blur the boundaries between science and policy and, in doing so, invent new epistemological communities of practice. 相似文献
340.
China’s influence on climate governance has been steadily increasing since the adoption of the Paris Agreement on climate change in 2015. Much of this influence, this article argues, has come from China forging a path for climate adaptation and mitigation for the global South. This is having far-reaching consequences, the article further argues, for the politics of global climate governance. China’s discursive and diplomatic power in climate politics is growing as China builds alliances across the global South. China is leveraging this enhanced soft power to elevate the importance of adaptation in multilateral climate negotiations, advance a technocentric approach to climate mitigation, export its development model, and promote industrial-scale afforestation as a nature-based climate solution. China’s strategy is enhancing climate financing, technology transfers, renewable power, and adaptation infrastructure across the global South. To some extent, this is helping with a transition to a low-carbon world economy. Yet China’s leadership is also reinforcing incremental, technocratic, and growth-oriented solutions in global climate governance. These findings advance the understanding of China’s role in global environmental politics, especially its growing influence on climate governance in the global South. 相似文献