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221.
Satoshi Someya Shigeru Bando Yongchen Song Baixin Chen Masahiro Nishio 《Journal of Oceanography》2004,60(4):789-795
We established a precise DeLIF (Dual Emission Laser Light Fluorescence) system for the instant measurement of the pH field
in laboratory experiments. This method is very important in studies of the biological impacts of CO2 sequestration, i.e., effects of pH on organisms. The technique is demonstrated by applying it to the pH measurement around
a liquid CO2 droplet, which has a large gradient of CO2 concentration near its interface, the concentration value on the boundary being known as the solubility of CO2. In the Laser Induced Fluorescence (LIF) method using quinine and an ultraviolet laser light source, the relatively unstable
pulse of the laser source decreased the measurement reliability. We therefore investigated many kinds of fluorescent dye and
demonstrated the DeLIF measurement, identifying a process for cancelling fluctuations of laser light intensity. Quinine and
sulforhodamine were used as fluorescence dyes. The molar absorption coefficient and emission intensity of quinine depend on
the pH of aqueous solutions, while those of sulforhodamine are not as much affected by pH. The ratio of these fluorescence
intensities represents pH at each point of the image. As a result, the pH field was successfully measured with an uncertainty
of only approximately ±0.005, for 3.0 < pH.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
222.
In order to estimate the distribution of pressure and transmissibility in the Otake Geothermal Reservoir, in which flow can be assumed to be two-dimensional and horizontal, well-head pressure and flow rates measured at both production and reinjection wells, and the time required for a tracer to arrive at certain production wells from one of the reinjection wells were analyzed. Analysis of these data was performed by means of an equation which was obtained by combining the Darcy and the continuity equations, in which the transmissibility and two components of the flow remain unknown. Estimation of pressure and transmissibility distributions and flow patterns within the reservoir was possible by numerical solution of this equation using the finite-difference method and by assuming suitable boundary conditions. 相似文献
223.
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225.
Hybridization of a Shallow 'I-type' Granitoid Pluton and its Host Migmatite by Magma-Chamber Wall Collapse: the Tokuwa Pluton, Central Japan 总被引:1,自引:0,他引:1
The Miocene Tokuwa pluton of I-type granitoidaffinity was emplaced discordantly into a Cretaceous to Paleogeneaccretionary complex and induced a contact aureole in whichvarious thermally metamorphosed rocks were developed, includinghornfels, metatexite, diatexite and cordierite-bearing tonalite(Crd-tonalite) of S-type granite affinity. Thethermally metamorphosed rocks show low-pressure reaction texturesculminating in partial melting. Peak PT conditions of3 kbar at 780°C are estimated on the basis of the TWQ thermobarometerfor the garnet-bearing rocks. The rocks in the contact aureoleexhibit a gradual transition from hornfels, through metatexiteand diatexite to Crd-tonalite. The Sr-isotopic composition atthe time of Tokuwa pluton emplacement at 12 Ma decreases systematicallyfrom metatexite (0·71000·7112) throughdiatexite (0·70780·7094) to Crd-tonalite(0·70670·7068); this trend is interpretedin terms of mixing between the Tokuwa magma and the aureolemigmatites. The field relationships, geochemical data, and isotopicdata collectively suggest that the emplacement of the Tokuwapluton triggered partial melting of the surrounding metasedimentaryrocks. Subsequent hybridization of the Tokuwa magma with themetatexite in variable proportions produced the Crd-tonaliteand diatexite. The hybridization was caused by invasion of theTokuwa magma into the migmatite zone, accompanied by gravitationalcollapse of the previously crystallized wall of the magma chamber.The data presented demonstrate that even a relatively low-temperature,shallow, I-type granitoid pluton can induce contactanatexis and hybrid S-type granitoid formationat the intrusive contact. KEY WORDS: contact metamorphism; hybridization; magmahost-rock interaction; migmatite; S-type granitoid 相似文献
226.
Hirotoshi Sakagami Nobuo Takahashi Akihiro Hachikubo Hirotsugu Minami Satoshi Yamashita Hitoshi Shoji Oleg Khlystov Gennadiy Kalmychkov Mikhail Grachev Marc De Batist 《Geo-Marine Letters》2012,32(5-6):465-472
Assessments of the molecular and isotopic composition of hydrate-bound and dissolved gases in pore water were conducted during the multi-phase gas hydrate project (MHP-09) cruise VER09-03 to the southern basin of Lake Baikal in September 2009. To avoid changes in gas composition during core sampling and transport, various headspace methods were investigated aimed at preserving the dissolved gases in pore water. When distilled water was added to the sediment samples, the concentrations of carbon dioxide and oxygen decreased because of dissolution into the water and/or microbial consumption. When the headspace was not flushed with inert gases, trace levels of hydrogen and ethylene were detected. The findings suggest that best preparation is achieved by flushing the headspace with helium, and adding a saturated aqueous solution of sodium chloride. This improved headspace method served to examine the molecular and isotopic compositions of gas samples retrieved at several new sites in the southern basin. Methane was the major component, and the proportion of ethane ranged widely from 0.0009 to 1.67?mol% of the total hydrocarbon gases. The proportions of propane and higher hydrocarbons were small or less than their detection limits. The carbon isotope signatures suggest that microbial-sourced methane and ethane were dominant in the Peschanka study area, whereas ethane was of thermogenic origin at all other study sites in the southern basin of Lake Baikal. 相似文献
227.
Interferometric synthetic aperture radar (InSAR) analysis is a radar technique for generating large-area maps of ground deformation using differences in the phase of microwaves returning to a satellite. In recent years, high-resolution SAR sensors have been developed that enable small-scale slope deformation to be detected, such as the partial block movement of a landslide. The L-band SAR (PALSAR-2) is mounted on Advanced Land Observing Satellite-2 (ALOS-2), which was launched on 24 Mar. 2014. Its main improvements compared with ALOS are enhanced resolution of as high as 3 m with a high-frequency recurrence period (14 days). Owing to its high resolution and the use of the L-band, PALSAR-2 can obtain reflective data passing through a tree canopy surface, unlike the other synthetic aperture radars. Therefore, the coherence of InSAR in mountainous forest areas is less likely to decrease, making it advantageous for the extraction of slope movement. In this study, to verify the accuracy of InSAR analysis using PALSAR-2 data, we compared the results of InSAR analysis and the measurement of the displacement in a landslide by global navigation satellite system (GNSS) observation. It was found that the average difference between the displacements obtained by InSAR analysis and the field measurements by GNSS was only 15.1 mm in the slant range direction, indicating the high accuracy of InSAR analysis. Many of the areas detected by InSAR analysis corresponded to the locations of surface changes due to landslide activity. Additionally, in the areas detected by InSAR analysis using multiple datasets, the ground changes due to landslide movement were confirmed by site investigation. 相似文献
228.
Phytoplankton community reorganization driven by eutrophication and warming in Lake Biwa 总被引:1,自引:0,他引:1
Chih Hao Hsieh Kanako Ishikawa Yoichiro Sakai Toshiyuki Ishikawa Satoshi Ichise Yoshimasa Yamamoto Ting Chun Kuo Ho Dong Park Norio Yamamura Michio Kumagai 《Aquatic Sciences - Research Across Boundaries》2010,72(4):467-483
We compiled and analyzed long-term data, including chemical, physical and phytoplankton community data, for the Lake Biwa
ecosystem from 1962 to 2003. Analyses on environmental data indicate that Lake Biwa had experienced intensified eutrophication
(according to total phosphorus concentration) in the late 1960s and returned to a less eutrophic status around 1985, and then
exhibited rapid warming and thus increased water column stability since 1990. Total phytoplankton cell volume largely followed
the trend of total phosphorus concentration, albeit short-term fluctuations existed. However, phytoplankton community shifted
dramatically in response to those changes of environmental states. These shifts were cause by changes in trophic status driven
by phosphorus loadings and physical properties in the water column driven by warming. Moreover, most phytoplankton species
did not show a strong linear correlation with environmental variables, suggesting nonlinear transitions among different states. 相似文献
229.
Satoshi Itaba Naoji Koizumi Norio Matsumoto Ryu Ohtani 《Pure and Applied Geophysics》2010,167(8-9):1105-1114
In 2006, we started construction of an observation network of 12 stations in and around Shikoku and the Kii Peninsula to conduct research for forecasting Tonankai and Nankai earthquakes. The purpose of the network is to clarify the mechanism of past preseismic groundwater changes and crustal deformation related to Tonankai and Nankai earthquakes. Construction of the network of 12 stations was completed in January 2009. Work on two stations, Hongu-Mikoshi (HGM) and Ichiura (ICU), was finished earlier and they began observations in 2007. These two stations detected strain changes caused by the slow-slip events on the plate boundary in June 2008, although related changes in groundwater levels were not clearly recognized. 相似文献
230.
浙江苍南瑶坑碱性花岗岩的地球化学及其成因类型 总被引:10,自引:0,他引:10
瑶坑岩体位于浙闽交界的苍南县马站镇北侧,侵入于早白垩世石帽山群下组地层中。岩石发育典型的文象结构和晶洞 构造,含有特征的钠铁闪石碱性铁镁矿物,主要矿物组合为石英+条纹长石+钠铁闪石+黑云母+萤石、锆石。化学成分上,该岩体富硅、碱、贫钙、镁,分异指数和氧化指数高,富Rb、Th、Ga,贫Sr、Ba,Ga/Al比值大,富轻稀土,Nb、Zr、Hf等高场强元素含量高,Cr、Co、Ni、V等过渡族元素显著亏损 相似文献