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人造气液包裹体方法在研究热液的物理化学性质方面较传统方法简便、易行。它可用于研究热液的等容线、不混溶性质及矿物在热液中的溶解度。本文解释了人造气液包裹体的合成方法和人造气液包裹体方法的原理,分述了应用此方法研究热液所取得的最新成果。此法不仅能用于研究热液的性质,也能用于其它方面的研究,具有广阔的前景。 相似文献
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Abstract Quartz-hosted, synthetic CO2 -H2 O fluid inclusions behave as open systems with respect to diffusional transfer of hydrogen during laboratory-simulated metamorphic re-equilibration at 650, 750 and 825°C and 1.5 kbar total pressure with fO2 defined by the C-CH4 buffer. Microthermometry and Raman spectroscopy show that the initial CO2 -H2 O inclusions become CO2 -CH4 -H2 -H2O
inclusions after diffusive influx of hydrogen from the reducing confining medium. Measurable changes are observed in inclusion compositions after only 15 days of re-equilibration, implying significant hydrogen mobility at still lower temperatures over geological time spans. Results of synthetic inclusion re-equilibrium experiments have profound implications for the interpretation of natural fluid-inclusion data; failure to account for potential hydrogen migration in inclusions from high-temperature geological environments may lead to erroneous estimates of P-T, and/or the compositions of metamorphic fluids. 相似文献
inclusions after diffusive influx of hydrogen from the reducing confining medium. Measurable changes are observed in inclusion compositions after only 15 days of re-equilibration, implying significant hydrogen mobility at still lower temperatures over geological time spans. Results of synthetic inclusion re-equilibrium experiments have profound implications for the interpretation of natural fluid-inclusion data; failure to account for potential hydrogen migration in inclusions from high-temperature geological environments may lead to erroneous estimates of P-T, and/or the compositions of metamorphic fluids. 相似文献
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Natural gas generation model and its response in accumulated fluids in the Yinggehai basin 总被引:2,自引:0,他引:2
The generation of natural gases is much more complicated in comparison with liquid petro-leum in that natural gases could be generated from both humic and sapropelic organic matter at different stages and that natural gases could be organic and inorganic … 相似文献
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Holdway DA 《Marine pollution bulletin》2002,44(3):185-203
A review of the acute and chronic effects of produced formation water (PFW), drilling fluids (muds) including oil-based cutting muds, water-based cutting muds, ester-based cutting muds and chemical additives, and crude oils associated with offshore oil and gas production was undertaken in relation to both temperate and tropical marine ecological processes. The main environmental effects are summarized, often in tabular form. Generally, the temporal and spatial scales of these studies, along with the large levels of inherent variation in natural environments, have precluded our ability to predict the potential long-term environmental impacts of the offshore oil and gas production industry. A series of critical questions regarding the environmental effects of the offshore oil and gas production industry that still remain unanswered are provided for future consideration. 相似文献
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The purpose of this work was to study jointly the volcanic-hydrothermal system of the high-risk volcano La Soufrière, in
the southern part of Basse-Terre, and the geothermal area of Bouillante, on its western coast, to derive an all-embracing
and coherent conceptual geochemical model that provides the necessary basis for adequate volcanic surveillance and further
geothermal exploration. The active andesitic dome of La Soufrière has erupted eight times since 1660, most recently in 1976–1977.
All these historic eruptions have been phreatic. High-salinity, Na–Cl geothermal liquids circulate in the Bouillante geothermal
reservoir, at temperatures close to 250 °C. These Na–Cl solutions rise toward the surface, undergo boiling and mixing with
groundwater and/or seawater, and feed most Na–Cl thermal springs in the central Bouillante area. The Na–Cl thermal springs
are surrounded by Na–HCO3 thermal springs and by the Na–Cl thermal spring of Anse à la Barque (a groundwater slightly mixed with seawater), which are
all heated through conductive transfer. The two main fumarolic fields of La Soufrière area discharge vapors formed through
boiling of hydrothermal aqueous solutions at temperatures of 190–215 °C below the "Ty" fault area and close to 260 °C below
the dome summit. The boiling liquid producing the vapors of the Ty fault area has δD and δ18O values relatively similar to those of the Na–Cl liquids of the Bouillante geothermal reservoir, whereas the liquid originating
the vapors of the summit fumaroles is strongly enriched in 18O, due to input of magmatic fluids from below. This process is also responsible for the paucity of CH4 in the fumaroles. The thermal features around La Soufrière dome include: (a) Ca–SO4 springs, produced through absorption of hydrothermal vapors in shallow groundwaters; (b) conductively heated, Ca–Na–HCO3 springs; and (c) two Ca–Na–Cl springs produced through mixing of shallow Ca–SO4 waters and deep Na–Cl hydrothermal liquids. The geographical distribution of the different thermal features of La Soufrière
area indicates the presence of: (a) a central zone dominated by the ascent of steam, which either discharges at the surface
in the fumarolic fields or is absorbed in shallow groundwaters; and (b) an outer zone, where the shallow groundwaters are
heated through conduction or addition of Na–Cl liquids coming from hydrothermal aquifer(s).
Received: 9 November 1998 / Accepted: 15 July 1999 相似文献
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