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111.
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113.
S. J. Gibowicz 《Pure and Applied Geophysics》1986,124(4-5):611-658
This review was prepared as an opening lecture for the International Symposium on Physics of Fracturing and Seismic Energy Release, held at the Castle of Liblice near Prague from October 28 to November 1, 1985, and organized by the Geophysical Institute of the Czechoslovak Academy of Sciences. The review attempts to classify and synthesize results of recent studies in fracture mechanics and earthquake source physics. The following topics are discussed: recent developments in fracture mechanics, earthquake source modeling, heterogeneous fault planes, foreshocks and aftershocks, faults and fractals, and moment tensor solutions. This rather broad range of topics prevents presentation of a complete list of all relevant works, though over one hundred and seventy references are cited. 相似文献
114.
Huadong Guo 《International Journal of Digital Earth》2018,11(6):546-557
Although Earth’s surface parameters obtained from satellite data have become more and more precise, it is still difficult to guarantee temporal consistency and spatial continuity for large-scale geoscience phenomena. Developing new Earth observation platforms is a feasible way to improve the consistency and continuity of such data. As the planet’s only natural satellite, the Moon has special advantages as a platform for observing Earth, including long lifetime, whole disk view, tectonic stability and unique perspective. After presenting the observation geometry constructed by using the ephemeris, this paper mainly discusses the characteristics of a lunar platform and the proper Moon-based sensors, as well as the scientific objectives of Moon-based Earth observation. Solid Earth dynamics, the energy budget of Earth, Earth’s environmental elements and the Earth-space environment are four potential applications analysed in this paper. 相似文献
115.
Ilia Rodushkin Emma Engström Douglas C. Baxter 《Geostandards and Geoanalytical Research》2007,31(1):27-38
The analytical performance of a method for Os isotope ratio measurement by double‐focusing, sector field ICP‐MS (ICP‐SFMS) was evaluated. The method is based on several optimised, concurrent processes: Os extraction from samples in hot concentrated nitric acid; separation of Os from the digest solution by the formation of volatile osmium tetroxide accelerated by continuous hydrogen peroxide addition; transport of analyte vapour by an oxygen flow into the ICP; and isotopic determination by ICP‐SFMS. Due to the very efficient utilisation of analyte (approaching 0.5‰), Os isotope ratio measurement could be performed at low pg levels. Combined with an ability to process sample sizes up to 2 g (up to 50 g if the organic matrix of biological or botanical samples is eliminated by ashing), materials with Os concentrations in the low, or even sub pg g?1 range could be determined by this method. Given that two complete digestion/distillation systems were available for interchangeable use, throughputs of up to fifteen samples per 8 hour shift could be achieved. The method precision, evaluated as the long‐term reproducibility of 187 Os/188Os ratio measurements in a commercial Os reference sample containing 0.5 ng Os, was 0.16% relative standard deviation (RSD, 1s). The method has been applied to perform replicate 187 Os/188 Os ratio measurements on a suite of fifty reference materials of various origins and matrix compositions, with Os concentrations varying from < 0.1 pg g?1 to > 100 ng g?1, yielding an average precision of 3% RSD. Though none of the materials tested are certified for Os content or Os isotope composition, comparison of the obtained data with published Os isotope information for similar sample types revealed close agreement between the two. The method can also be used for the simultaneous, semi‐quantitative determination of Os concentrations. 相似文献
116.
应用介质分界面上位移应力连续性的变化关系,采用δ矩阵法和固体层状介质中的瑞利波频散方程,推导了含流体介质夹层情况下瑞利波的频散方程。利用推导的频散方程对理论模型进行模拟计算,并与以往文献计算方法进行比较,模拟结果吻合较好,验证了公式的正确性;同时,模拟计算结果也说明了本文公式的普遍适用性和计算结果的完整性。根据文中对4个理论模型的模拟结果来看,与固体层状介质的情况相比,当存在流体夹层时,瑞利波频散曲线模式中多出了一个文中定义的0阶模式,在今后的多道瞬态瑞利波法应用中,应该可以将其看成是流体介质夹层存在的标志性曲线。 相似文献
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118.
Y. J. Lee R. J. Reeder R. W. Wenskus E. J. Elzinga 《Physics and Chemistry of Minerals》2002,29(9):585-594
Mn K-edge EXAFS spectroscopy of solid-solution samples encompassing the complete MnCO3–CaCO3 series shows that first-shell Mn–O distances deviate little from the 2.19-Å distance observed in pure MnCO3. Very slight lengthening is observed only in the limiting case of dilute Mn(II) calcite solid solutions, where the Mn–O distance is 2.21 Å. The observed nearly complete structural relaxation and the composition independence of the Mn–O distance are consistent with the Pauling model behavior of solid solutions, and agree with previous studies showing a high degree of relaxation around hetero-sized substituents in the calcite structure. Strain occurs through bond bending, which is facilitated by the exclusively corner-sharing topology of calcite. Observed distances from Mn to more distant neighbors show significant variation across the solid-solution series that resembles Vegard's law-type behavior but reflects averaging. The high degree of relaxation suggests modest enthalpies of mixing in the solution, consistent with calorimetric studies. 相似文献
119.
地层模型的三维实体显示与剖切 总被引:3,自引:0,他引:3
俞全宏 《物探化探计算技术》1996,18(1):60-66
本文介绍了地层模型的三维实体显示的原理与方法,同时又提出了沿任意方向垂直剖切地层模型的一种实用有效算法,它已用于交互式三维地层矿床显示系统GD-3DWS,是三维地质解释的很好工具 相似文献
120.
Polymetallic Mineralization at the Suttsu Vein-type Deposit, Southwestern Hokkaido, Japan 总被引:1,自引:0,他引:1
Abstract. The Suttsu polymetallic vein-type deposit, hosted by tuff, tuff breccia and shale of the Miocene Kunnui Formation and propylitized hornblende-augite andesite, is located in southwestern Hokkaido, Japan. It has been exploited and explored for Cu, Pb, Zn and Ag until 1962.
In this study, we examined K-Ar ages, ore mineralogical characteristics and fluid inclusions to obtain new data for the deposit.
The K-Ar ages on sericite indicate that the polymetallic mineralization occurred in Late Miocene (8.1–5.7 Ma). The polymetallic banded ore from the Ohkubo vein is characterized by an abundance of Au, Ag, Sn, Bi, in, Se and Te. These metals are mainly ascribed to electrum (30.3–37.8 atom% Ag), Se-bearing pavonite (8.5–9.5 wt% Se), gustavite-lillianite solid solution, Se-bearing bismuthinite (5.0–5.3 wt% Se), kawazulite, cassiterite, Sn-bearing chalcopyrite (3.3–4.2 wt% Sn), In-bearing stannite, stannite-chalcopyrite solid solution, and In- and Sn-bearing sphalerite (2.6–8.4 wt% In and 1.8–4.3 wt% Sn), occurring in narrow bands of the ore. The In- and Sn-bearing sphalerite likely forms a sphalerite-roquesite-stannite solid solution with the contents of roquesite and stannite being about 2–9 and 2-A mole%, respectively. Temperatures and salinities (in wt% NaCl equiv.) of the ore fluids are estimated to be 180-250C and 3–4 wt%, respectively. The Sn-bearing chalcopyrite therefore probably precipitated metastably. The geologic and mineralogical features suggest that pre-Tertiary basement rocks rich in organic material underlie the Miocene Kunnui Formation nearby the deposit and that they contributed to local and temporary reduction of magnetite-series magmas favorable for the early stage tin-polymetallic mineralization. 相似文献
In this study, we examined K-Ar ages, ore mineralogical characteristics and fluid inclusions to obtain new data for the deposit.
The K-Ar ages on sericite indicate that the polymetallic mineralization occurred in Late Miocene (8.1–5.7 Ma). The polymetallic banded ore from the Ohkubo vein is characterized by an abundance of Au, Ag, Sn, Bi, in, Se and Te. These metals are mainly ascribed to electrum (30.3–37.8 atom% Ag), Se-bearing pavonite (8.5–9.5 wt% Se), gustavite-lillianite solid solution, Se-bearing bismuthinite (5.0–5.3 wt% Se), kawazulite, cassiterite, Sn-bearing chalcopyrite (3.3–4.2 wt% Sn), In-bearing stannite, stannite-chalcopyrite solid solution, and In- and Sn-bearing sphalerite (2.6–8.4 wt% In and 1.8–4.3 wt% Sn), occurring in narrow bands of the ore. The In- and Sn-bearing sphalerite likely forms a sphalerite-roquesite-stannite solid solution with the contents of roquesite and stannite being about 2–9 and 2-A mole%, respectively. Temperatures and salinities (in wt% NaCl equiv.) of the ore fluids are estimated to be 180-250C and 3–4 wt%, respectively. The Sn-bearing chalcopyrite therefore probably precipitated metastably. The geologic and mineralogical features suggest that pre-Tertiary basement rocks rich in organic material underlie the Miocene Kunnui Formation nearby the deposit and that they contributed to local and temporary reduction of magnetite-series magmas favorable for the early stage tin-polymetallic mineralization. 相似文献