Recognition of shear heating on a long‐lived major fault using Raman carbonaceous material thermometry: implications for strength and displacement history of the MTL,SW Japan          下载免费PDF全文

Hiroshi Mori  Simon Wallis  Koichiro Fujimoto  Norio Shigematsu 《Island Arc》2015,24(4):425-446

The extent to which movement on major faults causes long term shear heating is a contentious issue and an important aspect in the debate about the strength of major faults in the crust. Comparing the results of experimental work on the kinetics of crystallization of carbonaceous material with results of thermal modeling show that the Raman carbonaceous material (CM) geothermometer is well suited to studying shear heating on geological time scales in suitable lithologies exposed around exhumed major fault zones. The Median Tectonic Line (MTL), SW Japan, is the largest on‐land fault in Japan with a length of > 800 km. Application of Raman CM thermometry to pelitic schist adjacent to the fault reveals the presence of a rise in peak temperature of around 60 °C over a distance of around 150 m perpendicular to the MTL fault plane. The spatial association of this thermal anomaly with the fault implies it is due to shear heating. Thermal modeling shows the recorded thermal anomaly and steep temperature gradient is compatible with very high rates of displacement over time scales of a few thousand years. However, the implied displacement rates lie outside those generally observed. An alternative explanation is that an originally broader thermal anomaly that developed during strike slip faulting was shortened due to the effects of normal faulting. Constraints on displacement rate, width of the original anomaly, duration of heating and peak temperature imply a coefficient of friction, μ, greater than 0.4.  相似文献   

Groundwater contamination in Japan     

Norio Tase 《Environmental Geology》1992,20(1):15-20

Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed.  相似文献   

Mineralogy and geothermometry of high-temperature rhyolites from the central and western Snake River Plain     

Norio Honjo  Bill Bonnichsen  William P Leeman  John C Stormer Jr 《Bulletin of Volcanology》1992,54(3):220-237

Voluminous mid-Miocene rhyolitic ash-flow tuffs and lava flows are exposed along the northern and southern margins of the central and western Snake River Plain. These rhyolites are essentially anhydrous with the general mineral assemblage of plagioclase ±sanidine ± quartz + augite + pigeonite ± hypersthene ± fayalitic olivine + Fe-Ti oxides + apatite + zircon which provides an opportunity to compare feldspar, pyroxene, and Fe-Ti oxide equilibration temperatures for the same rocks. Estimated pyroxene equilibration temperatures (based on the geothermometers of Lindsley and coworkers) range from 850 to 1000°C, and these are well correlated with whole-rock compositions. With the exception of one sample, agreement between the two-pyroxene thermometers tested is well within 50°C. Fe-Ti oxide geothermometers applied to fresh magnetite and ilmenite generally yield temperatures about 50 to 100°C lower than the pyroxene temperatures, and erratic results are obtained if these minerals exhibit effects of subsolidus oxidation and exsolution. Results of feldspar thermometry are more complicated, and reflect uncertainties in the thermometer calibrations as well as in the degree of attainment of equilibrium between plagioclase and sanidine. In general, temperatures obtained using the Ghiorso (1984) and Green and Usdansky (1986) feldspar thermometers agree with the pyroxene temperatures within the respective uncertainties. However, uncertainties in the feldspar temperatures are the larger of the two (and exceed ±60°C for many samples). The feldspar thermometer of Fuhrman and Lindsley (1988) produces systematically lower temperatures for many of the samples studied. The estimated pyroxene temperatures are considered most representative of actual magmatic temperatures for these rhyolites. This range of temperatures is significantly higher than those for rhyolites from many other suites, and is consistent with the hypothesis that the Snake River Plain rhyolitic magmas formed by partial fusion of relatively dry (e.g. granulitic) crustal lithologies.  相似文献   

Expansion of the Nishinomiya Built Environment Database     

Kohiyama  Masayuki  Yamashita  Norihiko  Sato  Tadanobu  Hengjian  Lu  Maki  Norio  Tanaka  Satoshi  Hayashi  Haruo 《Natural Hazards》2003,29(3):501-522

The Nishinomiya Built Environment Database, which can be used to analyze the disaster process of the 1995 Hanshin-Awaji Earthquake Disaster in Nishinomiya City, has been expanded with new data entries. The database contains the following very detailed datasets: (1) the urbanization area base map, (2) casualty data, (3) three sets of building damage data surveyed by the Nishinomiya City, the Architectural Institute of Japan and the City Planning Institute of Japan, and the Kobe University, (4) building property data based on the real estate tax roll, (5) photographs of the damaged buildings with the information on the place and orientation of the picture, and (6) the estimated distribution of the seismic ground motion. The seismic ground motion was simulated for the southern part of Nishinomiya City and two verification sites in Kobe City and Amagasaki City. In the simulation, the borehole data of public facilities were used to model the surface soils as one-dimensional layers, taking into consideration the fact that the spatial distribution of the sediment/basement interface forms a slope. The model of the fault rupture process simulated the characteristics of the seismic motion at basement level, and amplification effects of the surface layers were evaluated based on multiple reflection theory. The distribution of peak ground acceleration and peak ground velocity was estimated from acceleration response spectra at each borehole point. In addition, the relationship between simulated seismic ground motion and building damage was studied based on newly proposed band-passed spectrum intensity using the expanded database. This confirmed that detailed categorization is necessary in order to evaluate the fragility functions, especially for reinforced concrete structures. The database should provide fundamental information for identifying the relationship between the ground motions and the extent and pattern of building damage, or the pattern of the occurrence of casualties.Presently  相似文献   

Mechanism of the olivine–ringwoodite transformation in the presence of aqueous fluid     

Jun-ichi Ando  Naotaka Tomioka  Kazunari Matsubara  Toru Inoue  Tetsuo Irifune 《Physics and Chemistry of Minerals》2006,33(6):377-382

The mechanism of the high pressure transformation of olivine in the presence of aqueous fluid was investigated by high pressure experiments conducted nominally at the wadsleyite + ringwoodite stability field at 14.5 GPa and 700 and 800°C. The microstructures of recovered samples were observed using an analytical transmission electron microscope (ATEM) for which foils were prepared using a focused ion beam technique. Glass films approximately 1 μm in width always occupied the interface between olivine and hydrous ringwoodite. ATEM measurements showed that the chemical compositions of the glass films had approximately the same Mg/Fe ratio as that of olivine, but a higher Si content. Micro-structural and -chemical observations suggest that these glass films formed as quenched glass from the aqueous fluid dissolving olivine and that hydrous ringwoodite was crystallized from the fluid. This indicates that the transformation of olivine to hydrous ringwoodite was prompted by the dissolution–reprecipitation process. The dissolution–reprecipitation process is considered an important mineral replacement mechanism in the Earth’s crust by which one mineral is replaced by a more stable phase or phases. However, this process has not previously been reported for deep mantle conditions.  相似文献   

Distributed object‐based software environment for urban system integrated simulation under urban‐scale hazard—Part II: Application     

M. Hassanien Serror  Junya Inoue  Muneo Hori  Yozo Fujino  Tsuyoshi Ichimura 《地震工程与结构动力学》2007,36(11):1561-1579

A software prototype of a simulation service software environment, called DOSE (distributed object‐based software environment), is developed to realize the integrated simulation of an urban system under the risk of urban‐scale hazards such as earthquakes. DOSE infrastructure is built on three basic building blocks, namely: modularity, scalability, and interoperability. In this paper, the application of DOSE to real‐world urban systems is described in order to provide an evidence for DOSE modularity and scalability. An overview of DOSE is presented and then followed by a beverage application to simulate earthquake hazard in an urban system. The urban system is developed for the city of Kobe (Kobe district) with dimensions of 700 × 500 (m) and Bunkyo ward (Tokyo district) with dimensions of 800 × 600 (m) where DOSE simulation participants are identified for each district. The effectiveness of data exchange among different participants through a distributed service exchange network is described as an evidence for DOSE modularity that facilitates the integration process. On the other hand, the effectiveness of processing time when applying the simulation to different urban system sizes and/or using different third‐party applications is described as an evidence for DOSE scalability. The details of the underlying infrastructure of DOSE are beyond the scope of this paper and are presented in an accompanying paper work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

Distributed object‐based software environment for urban system integrated simulation under urban‐scale hazard—Part I: Infrastructure     

M. Hassanien Serror  Junya Inoue  Muneo Hori  Yozo Fujino 《地震工程与结构动力学》2007,36(11):1545-1560

In this paper, a distributed object‐based software environment (DOSE) has been developed to facilitate the integrated simulation of an urban system under the risk of urban‐scale hazards such as earthquakes. It is understood that individual simulation participants perform their simulation services in separate environments, bartering service exchange relationships to get what they need to resolve their part of the problem. This is the communication gap between the scientists on one side and the end users who need to understand knowledge and employ it on the other side. The authors envision a distributed simulation service software environment running in parallel with the activities of simulation participants. DOSE has lent itself to integrate interdisciplinary participants through an infrastructure that has three basic building blocks, namely: modularity, scalability, and interoperability. The modular, object‐based, design of DOSE architecture is described in terms of key functionalities of four distinct layers, namely: resource, core, domain, and interface layers. DOSE scalability in terms of urban system size and participant third‐party application complexity is enabled through the interface layer. A message passing model is developed using the Message Passing Interface standard and a control room is provided to schedule the interaction/communication among model processes. DOSE interoperability with the vulnerability analysis third‐party applications is enabled through the Industry Foundation Classes (IFC) standard. An adopted analogy between DOSE and construction industry is employed to provide interpretation and implementation for DOSE interoperability. While interfacing IFC object model to solve DOSE interoperability questions, an extension model for the structural view of IFC is proposed and accepted by the International Alliance for Interoperability. The DOSE application for real‐world urban systems is beyond the scope of this paper and is presented in an accompanying paper work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

Origins of building blocks of life: A review     

Norio Kitadai  Shigenori Maruyama 《地学前缘(英文版)》2018,(4)

How and where did life on Earth originate? To date, various environments have been proposed as plausible sites for the origin of life. However, discussions have focused on a limited stage of chemical evolution, or emergence of a specific chemical function of proto-biological systems. It remains unclear what geochemical situations could drive all the stages of chemical evolution, ranging from condensation of simple inorganic compounds to the emergence of self-sustaining systems that were evolvable into modern biological ones. In this review, we summarize reported experimental and theoretical findings for prebiotic chemistry relevant to this topic, including availability of biologically essential elements(N and P) on the Hadean Earth, abiotic synthesis of life's building blocks(amino acids, peptides, ribose, nucleobases, fatty acids, nucleotides, and oligonucleotides), their polymerizations to bio-macromolecules(peptides and oligonucleotides), and emergence of biological functions of replication and compartmentalization. It is indicated from the overviews that completion of the chemical evolution requires at least eight reaction conditions of(1) reductive gas phase,(2) alkaline pH,(3) freezing temperature,(4)fresh water,(5) dry/dry-wet cycle,(6) coupling with high energy reactions,(7) heating-cooling cycle in water, and(8) extraterrestrial input of life's building blocks and reactive nutrients. The necessity of these mutually exclusive conditions clearly indicates that life's origin did not occur at a single setting; rather, it required highly diverse and dynamic environments that were connected with each other to allow intratransportation of reaction products and reactants through fluid circulation. Future experimental research that mimics the conditions of the proposed model are expected to provide further constraints on the processes and mechanisms for the origin of life.  相似文献   

Factors Controlling the Fractionation and Seasonal Mobility Variations of Ga and In in Systems Impacted by Acidic Thermal Waters: Effects of Thermodynamics and Bacterial Activity     

Yasumasa Ogawa  Daizo Ishiyama  Naotatsu Shikazono  Koichi Suto  Chihiro Inoue  Noriyoshi Tsuchiya  Bernhardt Saini-Eidukat  Scott A. Wood 《Aquatic Geochemistry》2018,24(1):5-25

This work assessed both the fractionation and the seasonal mobility variations of Ga and In in systems impacted by acidic thermal waters. This was accomplished by performing thermodynamic calculations using the PHREEQC algorithm and by assessing the activity of acidophilic iron-oxidizing bacteria. The pH of the Kusatsu thermal waters in Gunma Prefecture, central Japan, is rapidly increased following the addition of a lime suspension. After an abrupt pH increase, under which conditions free ions of Ga and In and their complexes with Cl^? and SO₄^2? exist only in negligible quantities, the majority of dissolved Ga and In is removed by sorption onto suspended hydrous ferric oxides (HFOs). These HFOs are then transported to an artificial lake without significant sedimentation along the river. Subsequently, the suspended HFOs settle out and are added to sediments without significant fractionation between Ga and In. The Tamagawa thermal waters in Akita Prefecture, northeast Japan, are also treated with lime. However, complete neutralization requires mixing with some tributary streams, leading to a gradual downstream increase in pH. Dissolved Ga is, in general, sorbed by HFOs in upstream areas, leading to wide dispersal of Ga across the entire watershed. In comparison, In is transported to the lake inlet predominantly as a Cl^? complex species without significant removal along the river, with the majority being precipitated in an artificial lake, where Cl^? concentrations are too low to form stable complex species with In, and thus, dissolved In is sorbed by HFOs. As a result, In is effectively concentrated within downstream lakebed sediments, whereas Ga is dispersed along the river. Seasonal variations in Ga mobility within the Tamagawa field between snowmelt and low-flow seasons are primarily controlled by pH, because hydrolysis reactions of these metals, which are related to sorption reactions, tend to occur in the upstream regions in the snowmelt season. However, under warmer conditions, HFO formation preferably occurs due to the activity of acidophilic iron-oxidizing bacteria. Thus, under similar pH variations, dissolved Ga is more effectively removed by HFOs during warmer seasons. On the contrary, because HFOs are abundantly formed in low-flow season, even under colder conditions, before In hydrolysis reaction starts to occur, In mobility is less affected by water temperature and then bacterial activity.  相似文献   

Cep A: A possible proto-cluster     

Saeko S. Hayashi  Norio Kaifu  Tetsuo Hasegawa 《Astrophysics and Space Science》1986,119(1):155-157

We present high resolution CS and CO maps of Cep A region made with the 45m telescope at Nobeyama. The CS map shows that a dense cloud surrounding the proto-star cluster extends in the North-South direction and is probably rotating. The bipolar molecular flow apparent in the CO maps is well-collimated along East-West direction within 0.2 pc from the proto-stars. The dense cloud is gravitationally unstable and appears to be in a contracting phase to form a cluster of massive stars.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.NRO, a branch of the Tokyo Astronomical Observatory, University of Tokyo, is a cosmic radio observing facility open for outside users.  相似文献