Sample records for previous seismic studies

  1. Seismic Studies

    R. Quittmeyer


    This technical work plan (TWP) describes the efforts to develop and confirm seismic ground motion inputs used for preclosure design and probabilistic safety 'analyses and to assess the postclosure performance of a repository at Yucca Mountain, Nevada. As part of the effort to develop seismic inputs, the TWP covers testing and analyses that provide the technical basis for inputs to the seismic ground-motion site-response model. The TWP also addresses preparation of a seismic methodology report for submission to the U.S. Nuclear Regulatory Commission (NRC). The activities discussed in this TWP are planned for fiscal years (FY) 2006 through 2008. Some of the work enhances the technical basis for previously developed seismic inputs and reduces uncertainties and conservatism used in previous analyses and modeling. These activities support the defense of a license application. Other activities provide new results that will support development of the preclosure, safety case; these results directly support and will be included in the license application. Table 1 indicates which activities support the license application and which support licensing defense. The activities are listed in Section 1.2; the methods and approaches used to implement them are discussed in more detail in Section 2.2. Technical and performance objectives of this work scope are: (1) For annual ground motion exceedance probabilities appropriate for preclosure design analyses, provide site-specific seismic design acceleration response spectra for a range of damping values; strain-compatible soil properties; peak motions, strains, and curvatures as a function of depth; and time histories (acceleration, velocity, and displacement). Provide seismic design inputs for the waste emplacement level and for surface sites. Results should be consistent with the probabilistic seismic hazard analysis (PSHA) for Yucca Mountain and reflect, as appropriate, available knowledge on the limits to extreme ground

  2. Studies on seismic waves

    张海明; 陈晓非


    The development of seismic wave study in China in the past four years is reviewed. The discussion is divided into several aspects, including seismic wave propagation in laterally homogeneous media, laterally heterogeneous media, anisotropic and porous media, surface wave and seismic wave inversion, and seismic wave study in prospecting and logging problems. Important projects in the current studies on seismic wave is suggested as the development of high efficient numerical methods, and applying them to the studies of excitation and propagation of seismic waves in complex media and strong ground motion, which will form a foundation for refined earthquake hazard analysis and prediction.

  3. Studies on seismic source

    李世愚; 陈运泰


    During the period of 1999~2002, the Chinese seismologists made a serious of developments in the study on seismic sources including observations, experiments and theory. In the field of observation, the methods of the accuracy location of earthquake sources, the inversion of seismic moment tensor and the mechanism of earthquake source are improved and developed. A lot of important earthquake events are studied by using these methods. The rupture processes of these events are inverted and investigated combined with the local stress fields and the tectonic moment by using the measurements of surface deformation. In the fields of experiments and theory, many developments are obtained in cause of seismic formation, condition of stress and tectonics, dynamics of earthquake rupture, rock fracture and nucleation of strong earthquakes.

  4. Seismic hazard studies in Egypt

    Mohamed, Abuo El-Ela A.; El-Hadidy, M.; Deif, A.; Abou Elenean, K.


    The study of earthquake activity and seismic hazard assessment of Egypt is very important due to the great and rapid spreading of large investments in national projects, especially the nuclear power plant that will be held in the northern part of Egypt. Although Egypt is characterized by low seismicity, it has experienced occurring of damaging earthquake effect through its history. The seismotectonic sitting of Egypt suggests that large earthquakes are possible particularly along the Gulf of Aqaba-Dead Sea transform, the Subduction zone along the Hellenic and Cyprean Arcs, and the Northern Red Sea triple junction point. In addition some inland significant sources at Aswan, Dahshour, and Cairo-Suez District should be considered. The seismic hazard for Egypt is calculated utilizing a probabilistic approach (for a grid of 0.5° × 0.5°) within a logic-tree framework. Alternative seismogenic models and ground motion scaling relationships are selected to account for the epistemic uncertainty. Seismic hazard values on rock were calculated to create contour maps for four ground motion spectral periods and for different return periods. In addition, the uniform hazard spectra for rock sites for different 25 periods, and the probabilistic hazard curves for Cairo, and Alexandria cities are graphed. The peak ground acceleration (PGA) values were found close to the Gulf of Aqaba and it was about 220 gal for 475 year return period. While the lowest (PGA) values were detected in the western part of the western desert and it is less than 25 gal.

  5. Seismic hazard studies in Egypt

    Abuo El-Ela A. Mohamed


    Full Text Available The study of earthquake activity and seismic hazard assessment of Egypt is very important due to the great and rapid spreading of large investments in national projects, especially the nuclear power plant that will be held in the northern part of Egypt. Although Egypt is characterized by low seismicity, it has experienced occurring of damaging earthquake effect through its history. The seismotectonic sitting of Egypt suggests that large earthquakes are possible particularly along the Gulf of Aqaba–Dead Sea transform, the Subduction zone along the Hellenic and Cyprean Arcs, and the Northern Red Sea triple junction point. In addition some inland significant sources at Aswan, Dahshour, and Cairo-Suez District should be considered. The seismic hazard for Egypt is calculated utilizing a probabilistic approach (for a grid of 0.5° × 0.5° within a logic-tree framework. Alternative seismogenic models and ground motion scaling relationships are selected to account for the epistemic uncertainty. Seismic hazard values on rock were calculated to create contour maps for four ground motion spectral periods and for different return periods. In addition, the uniform hazard spectra for rock sites for different 25 periods, and the probabilistic hazard curves for Cairo, and Alexandria cities are graphed. The peak ground acceleration (PGA values were found close to the Gulf of Aqaba and it was about 220 gal for 475 year return period. While the lowest (PGA values were detected in the western part of the western desert and it is less than 25 gal.

  6. A study on seismicity and seismic hazard for Karnataka State

    T G Sitharam; Naveen James; K S Vipin; K Ganesha Raj


    This paper presents a detailed study on the seismic pattern of the state of Karnataka and also quantifies the seismic hazard for the entire state. In the present work, historical and instrumental seismicity data for Karnataka (within 300 km from Karnataka political boundary) were compiled and hazard analysis was done based on this data. Geographically, Karnataka forms a part of peninsular India which is tectonically identified as an intraplate region of Indian plate. Due to the convergent movement of the Indian plate with the Eurasian plate, movements are occurring along major intraplate faults resulting in seismic activity of the region and hence the hazard assessment of this region is very important. Apart from referring to seismotectonic atlas for identifying faults and fractures, major lineaments in the study area were also mapped using satellite data. The earthquake events reported by various national and international agencies were collected until 2009. Declustering of earthquake events was done to remove foreshocks and aftershocks. Seismic hazard analysis was done for the state of Karnataka using both deterministic and probabilistic approaches incorporating logic tree methodology. The peak ground acceleration (PGA) at rock level was evaluated for the entire state considering a grid size of 0.05° × 0.05°. The attenuation relations proposed for stable continental shield region were used in evaluating the seismic hazard with appropriate weightage factors. Response spectra at rock level for important Tier II cities and Bangalore were evaluated. The contour maps showing the spatial variation of PGA values at bedrock are presented in this work.

  7. Incorporating induced seismicity in the 2014 United States National Seismic Hazard Model: results of the 2014 workshop and sensitivity studies

    Petersen, Mark D.; Mueller, Charles S.; Moschetti, Morgan P.; Hoover, Susan M.; Rubinstein, Justin L.; Llenos, Andrea L.; Michael, Andrew J.; Ellsworth, William L.; McGarr, Arthur F.; Holland, Austin A.; Anderson, John G.


    The U.S. Geological Survey National Seismic Hazard Model for the conterminous United States was updated in 2014 to account for new methods, input models, and data necessary for assessing the seismic ground shaking hazard from natural (tectonic) earthquakes. The U.S. Geological Survey National Seismic Hazard Model project uses probabilistic seismic hazard analysis to quantify the rate of exceedance for earthquake ground shaking (ground motion). For the 2014 National Seismic Hazard Model assessment, the seismic hazard from potentially induced earthquakes was intentionally not considered because we had not determined how to properly treat these earthquakes for the seismic hazard analysis. The phrases “potentially induced” and “induced” are used interchangeably in this report, however it is acknowledged that this classification is based on circumstantial evidence and scientific judgment. For the 2014 National Seismic Hazard Model update, the potentially induced earthquakes were removed from the NSHM’s earthquake catalog, and the documentation states that we would consider alternative models for including induced seismicity in a future version of the National Seismic Hazard Model. As part of the process of incorporating induced seismicity into the seismic hazard model, we evaluate the sensitivity of the seismic hazard from induced seismicity to five parts of the hazard model: (1) the earthquake catalog, (2) earthquake rates, (3) earthquake locations, (4) earthquake Mmax (maximum magnitude), and (5) earthquake ground motions. We describe alternative input models for each of the five parts that represent differences in scientific opinions on induced seismicity characteristics. In this report, however, we do not weight these input models to come up with a preferred final model. Instead, we present a sensitivity study showing uniform seismic hazard maps obtained by applying the alternative input models for induced seismicity. The final model will be released after

  8. The assessment of seismic hazard for Gori, (Georgia) and preliminary studies of seismic microzonation

    Gogoladze, Z.; Moscatelli, M.; Giallini, S.; Avalle, A.; Gventsadze, A.; Kvavadze, N.; Tsereteli, N.


    Seismic risk is a crucial issue for South Caucasus, which is the main gateway between Asia and Europe. The goal of this work is to propose new methods and criteria for defining an overall approach aimed at assessing and mitigating seismic risk in Georgia. In this reguard seismic microzonation represents a highly useful tool for seismic risk assessmentin land management, for design of buildings or structures and for emergency planning.Seismic microzonation assessment of local seismic hazard,which is a component of seismicity resulting from specific local characteristics which cause local amplification and soil instability, through identification of zones with seismically homogeneous behavior. This paper presents the results of preliminary study of seismic microzonation of Gori, Georgia. Gori is and is located in the Shida Kartli region and on both sides of Liachvi and Mtkvari rivers, with area of about 135 km2around the Gori fortress. Gori is located in Achara-Trialeti fold-thrust belt, that is tectonically unstable. Half of all earthquakes in Gori area with magnitude M≥3.5 have happened along this fault zone and on basis of damage caused by previous earthquakes, this territory show the highest level of risk (the maximum value of direct losses) in central part of the town. The seismic microzonation map of level 1 for Gori was carried out using: 1) Already available data (i.e., topographic map and boreholes data), 2) Results of new geological surveys and 3) Geophysical measurements (i.e., MASW and noise measurements processed with HVSR technique). Our preliminary results highlight the presence of both stable zones susceptible to local amplifications and unstable zones susceptible to geological instability. Our results are directed to establish set of actions aimed at risk mitigation before initial onset of emergency, and to management of the emergency once the seismic event has occurred. The products obtained, will contain the basic elements of an integrated system


    SONG Haibin


    We give a brief introduction of developments of seismic methods in the studies of marine gas hydrates. Then we give an example of seismic data processing for BSRs in western Nankai accretionary prism, a typical gas hydrate distribution region. Seismic data processing is proved to be important to obtain better images of BSRs distribution. Studies of velocity structure of hydrated sediments are useful for better understanding the distribution of gas hydrates. Using full waveform inversion, we successfully derived high-resolution velocity model of a double BSR in eastern Nankai Trough area. Recent survey and research show that gas hydrates occur in the marine sediments of the South China Sea and East China Sea.But we would like to say seismic researches on gas hydrate in China are very preliminary.

  10. Lunar seismic profiling experiment natural activity study

    Duennebier, F. K.


    The Lunar Seismic Experiment Natural Activity Study has provided a unique opportunity to study the high frequency (4-20 Hz) portion to the seismic spectrum on the moon. The data obtained from the LSPE was studied to evaluate the origin and importance of the process that generates thermal moonquakes and the characteristics of the seismic scattering zone at the lunar surface. The detection of thermal moonquakes by the LSPE array made it possible to locate the sources of many events and determine that they are definitely not generated by astronaut activities but are the result of a natural process on the moon. The propagation of seismic waves in the near-surface layers was studied in a qualitative manner. In the absence of an adequate theoretical model for the propagation of seismic waves in the moon, it is not possible to assign a depth for the scattering layer. The LSPE data does define several parameters which must be satisfied by any model developed in the future.

  11. A Preliminary Study on Seismicity and Stages of Seismic Energy Accumulation in Seismotectonic Regions of Tianshan

    Li Yingzhen; Shen Jun; Wang Haitao


    Using seismic parameters, the characteristics of the seismic activity in various seismotectonic regions of Tianshan were studied in this paper. These regions are going through different stages of seismic energy accumulation. Current seismic risk levels of these areas were analyzed synthetically by the tectonic movement rates, as well as the characteristics of the seismic activity and the recurrence intervals of strong earthquakes. We preliminarily studied the characteristics of seismic activity in different seismic energy accumulating stages. The result shows that the characteristics of the seismic activity in various seismotectonic regions of the Tianshan area are influenced, not only by the regional tectonic movement, but also by the energy accumulating stage of various seismic tectonics. In the intense tectonic movement areas, it is important to estimate its stage of energy accumulating in order to predict the upper limit of the potential earthquake magnitude. In the less intense tectonic movement areas, the estimating of the stage of energy accumulation will help us recognize the dangerous level of the potential strong earthquake. The study shows that the seismotectonic regions in southern Tianshan have reached the mid-stage and late-stage of energy accumulation, with a higher seismic activity and thus a higher seismic dangerous level than those in the northern and middle Tianshan. The earthquake risk of southern Tianshan is up to Ms7.0, while that of the middle Tianshan is up to Ms6.0 and that of northern Tianshan is only around Ms5.0 ~ 6.0.

  12. Studying propagation of seismic waves across the Valley of Mexico from correlations of seismic noise

    Rivet, D. N.; Campillo, M.; Shapiro, N. M.; Singh, S.; Cruz Atienza, V. M.; Quintanar, L.; Valdés, C.


    We reconstruct Rayleigh and Love waves from cross-correlations of ambient seismic noise recorded at 22 broad-band stations of the MesoAmerica Seismic Experiment (MASE) and Valley of Mexico Experiment (VMEX). The cross-correlations are computed over 2 years of noise data for the 9 MASE stations and over 1 year for the 13 VMEX stations. Surface waves with sufficient signal-to-noise ratio are then used in the group velocity dispersion analysis. We use the reconstructed waveforms to measure group velocity dispersion curves at period of 0.5 to 5 seconds. For traveling path inside the lake-bed zone, the maximum energy is observed at velocity higher than expected for the fundamental mode. This indicates that the propagation within the Mexico basin is dominated by higher modes of surface waves that propagate deeper in the basin. We identify the propagation modes by comparing observations with theoretical dispersion curves and eigenfunctions calculated for Rayleigh and Loves waves associated with a given model of the upper crust. The fundamental mode shows a very low group velocity, <100m/s, which is consistent with previous studies. The domination of the higher modes in the Valley of Mexico may be a determining factor in the long duration of the seismic signal. A better velocity constraint on the deeper structure of the basin is thus needed to fully understand this phenomenon.

  13. Study on attribute characterization for reservoir dynamic monitoring by seismic


    Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

  14. Study on Seismic Zoning of Sino-Mongolia Arc Areas

    Xu, G.


    According to the agreement of Cooperation on seismic zoning between Institute of Geophysics, China Earthquake Administration and Research Center of Astronomy and Geophysics, Mongolian Academy of Science, the data of geotectonics, active faults, seismicity and geophysical field were collected and analyzed, then field investigation proceeded for Bolnay Faults, Ar Hutul Faults and Gobi Altay Faults, and a uniform earthquake catalogue of Mongolia and North China were established for the seismic hazard study in Sino-Mongolia arc areas. Furthermore the active faults and epicenters were mapped and 2 seismic belts and their 54 potential seismic sources are determined. Based on the data and results above mentioned the seismicity parameters for the two seismic belts and their potential sources were studied. Finally, the seismic zoning with different probability in Sino-Mongolia arc areas was carried out using China probabilistic hazard analysis method. By analyzing the data and results, we draw the following main conclusions. Firstly, the origin of tectonic stress field in the study areas is the collision and pressure of the India Plate to Eurasian Plate, passing from the Qinghai-Tibet Plateau. This is the reason why the seismicity is higher in the west than in the east, and all of earthquakes with magnitude 8 or greater occurred in the west. Secondly, the determination of the 2 arc seismic belts, Altay seismic belt and Bolnay-Baikal seismic belt, are reasonable in terms of their geotectonic location, geodynamic origin and seismicity characteristics. Finally, there are some differences between our results and the Mongolia Intensity Zoning map published in 1985 in terms of shape of seismic zoning map, especially in the areas near Ulaanbaatar. We argue that our relsults are reasonable if we take into account the data use of recent study of active faults and their parameters, so it can be used as a reference for seismic design.

  15. Study of Seismic Activity at Ceboruco Volcano, Mexico

    Nunez-Cornu, F. J.; Escudero, C. R.; Rodríguez Ayala, N. A.; Suarez-Plascencia, C.


    risk that represent to the surrounding communities and economic activities. Since March 2012 we installed four seismic stations, each includes a digital acquisition system TAURUS of Nanometrics and a Lennartz 3D lite (1Hz) seismometer. Batteries are change and data collected monthly. We use the data to establish the average seismic activity rate; we also aim to corroborate previous studies that showed four families of seismic events; and to localize and make preliminary evaluations of the events.

  16. Ground motion input in seismic evaluation studies

    Sewell, R.T.; Wu, S.C.


    This report documents research pertaining to conservatism and variability in seismic risk estimates. Specifically, it examines whether or not artificial motions produce unrealistic evaluation demands, i.e., demands significantly inconsistent with those expected from real earthquake motions. To study these issues, two types of artificial motions are considered: (a) motions with smooth response spectra, and (b) motions with realistic variations in spectral amplitude across vibration frequency. For both types of artificial motion, time histories are generated to match target spectral shapes. For comparison, empirical motions representative of those that might result from strong earthquakes in the Eastern U.S. are also considered. The study findings suggest that artificial motions resulting from typical simulation approaches (aimed at matching a given target spectrum) are generally adequate and appropriate in representing the peak-response demands that may be induced in linear structures and equipment responding to real earthquake motions. Also, given similar input Fourier energies at high-frequencies, levels of input Fourier energy at low frequencies observed for artificial motions are substantially similar to those levels noted in real earthquake motions. In addition, the study reveals specific problems resulting from the application of Western U.S. type motions for seismic evaluation of Eastern U.S. nuclear power plants.

  17. Comparative study of codes for the seismic design of structures

    S. H. C. Santos

    Full Text Available A general evaluation of some points of the South American seismic codes is presented herein, comparing them among themselves and with the American Standard ASCE/SEI 7/10 and with the European Standard Eurocode 8. The study is focused in design criteria for buildings. The Western border of South America is one of the most seismically active regions of the World. It corresponds to the confluence of the South American and Nazca plates. This region corresponds roughly to the vicinity of the Andes Mountains. This seismicity diminishes in the direction of the comparatively seismically quieter Eastern South American areas. The South American countries located in its Western Border possess standards for seismic design since some decades ago, being the Brazilian Standard for seismic design only recently published. This study is focused in some critical topics: definition of the recurrence periods for establishing the seismic input; definition of the seismic zonation and design ground motion values; definition of the shape of the design response spectra; consideration of soil amplification, soil liquefaction and soil-structure interaction; classification of the structures in different importance levels; definition of the seismic force-resisting systems and respective response modification coefficients; consideration of structural irregularities and definition of the allowable procedures for the seismic analyses. A simple building structure is analyzed considering the criteria of the several standards and obtained results are compared.

  18. A previously unreported type of seismic source in the firn layer of the East Antarctic Ice Sheet

    Lough, Amanda C.; Barcheck, C. Grace; Wiens, Douglas A.; Nyblade, Andrew; Anandakrishnan, Sridhar


    We identify a unique type of seismic source in the uppermost part of the East Antarctic Ice Sheet recorded by temporary broadband seismic arrays in East Antarctica. These sources, termed "firnquakes," are characterized by dispersed surface wave trains with frequencies of 1-10 Hz detectable at distances up to 1000 km. Events show strong dispersed Rayleigh wave trains and an absence of observable body wave arrivals; most events also show weaker Love waves. Initial events were discovered by standard detection schemes; additional events were then detected with a correlation scanner using the initial arrivals as templates. We locate sources by determining the L2 misfit for a grid of potential source locations using Rayleigh wave arrival times and polarization directions. We then perform a multiple-filter analysis to calculate the Rayleigh wave group velocity dispersion and invert the group velocity for shear velocity structure. The resulting velocity structure is used as an input model to calculate synthetic seismograms. Inverting the dispersion curves yields ice velocity structures consistent with a low-velocity firn layer ~100 m thick and show that velocity structure is laterally variable. The absence of observable body wave phases and the relative amplitudes of Rayleigh waves and noise constrain the source depth to be less than 20 m. The presence of Love waves for most events suggests the source is not isotropic. We propose the events are linked to the formation of small crevasses in the firn, and several events correlate with shallow crevasse fields mapped in satellite imagery.

  19. Previous studies underestimate BMAA concentrations in cycad flour.

    Cheng, Ran; Banack, Sandra Anne


    The traditional diet of the Chamorro people of Guam has high concentrations of the neurotoxin BMAA, beta-methyl-amino-L-alanine, in cycad tortillas and from animals that feed on cycad seeds. We measured BMAA concentration in washed cycad flour and compared different extraction methods used by previous researchers in order to determine how much BMAA may have been unaccounted for in prior research. Samples were analyzed with AQC precolumn derivatization using HPLC-FD detection and verified with UPLC-UV, UPLC-MS, and triple quadrupole LC/MS/MS. Although previous workers had studied only the free amino acid component of BMAA in washed cycad flour, we detected significant levels of protein-associated BMAA in washed cycad flour. These data support a link between ALS/PDC and exposure to BMAA.

  20. Combined Studies of ODP log Data and Seismic Reflection Data at Southern Hydrate Ridge

    Papenberg, C. A.; Petersen, J.; Klaeschen, D.


    In August 2002 Ocean Drilling Program (ODP) Leg 204 (Hydrate Ridge) provided essential borehole data to complement recent seismic studies at Hydrate Ridge to correlate amplitude analysis investigations and to constrain previous results. Seismic data was acquired during cruise SO-150 in September 2000 on the German RV SONNE, aiming at qualitative and quantitative estimates of free gas and gas hydrates within the sediments across Hydrate Ridge. Hydrate Ridge is part of the accretionary complex and is characterized by the presence of extensive gas hydrates, causing a prominent Bottom Simulating Reflector (BSR) in marine seismic records. Several seismic in- and crosslines were shot across the ridge to map the spatial distribution of the BSR. Wide angle reflection data of narrowly spaced Ocean Bottom Seismometers (OBS) allow frequency dependent amplitude variations with offset (AVO) investigations. Seismic reflection data, recorded simultaneously with a single channel surface and deep tow streamer completed the data set. The usage of different sources during acquisition provided additional information of the frequency response of the BSR signature. This data set was used to study the complex seismic behaviour of such gas hydrate environments in detail. The borehole data, collected during ODP Leg 204, now improve recent seismic investigations and support previous results. Within the COLIBRI project log information (Vp, Vs and density) was used for forward modeling to combine seismic investigations with new borehole data. The P wave velocity model of a traveltime inversion and AVO analysis of the seismic OBS sections suggest rather low quantities of gas hydrate or at least the lack of massive hydrate zones. Shear wave phases, identified in the seismic OBS sections, refer to slow S wave velocities in the upper sediment layers above the BSR, which support a model with small amounts of hydrate or patchy hydrate zones within the upper sediments.

  1. Statistical Seismology Studies in Central America : b-value, seismic hazard and seismic quiescence


    The present thesis collects results of research applying theory and methods of statistical seismology to the seismicity of Central America, a region with a complex tectonic setting controlled by the interaction of four major plates, namely the Caribbean, Cocos, Nazca and North American plates. Three different earthquake catalogues were used for studies focused on stress in a tectonic volume, seismic hazard maps and seismicity patterns (precursors), covering the region 94ºW to 81ºW and 5ºN to ...

  2. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    Karyono, E-mail: [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia); OSLO University (Norway); Padjadjaran University (UNPAD), Bandung (Indonesia); Mazzini, Adriano; Sugiharto, Anton [OSLO University (Norway); Lupi, Matteo [ETH Zurich (Switzerland); Syafri, Ildrem [Padjadjaran University (UNPAD), Bandung (Indonesia); Masturyono,; Rudiyanto, Ariska; Pranata, Bayu; Muzli,; Widodo, Handi Sulistyo; Sudrajat, Ajat [Agency for Meteorology, Climatology and Geophysics (BMKG), Jakarta (Indonesia)


    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green’s functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  3. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    Karyono, Mazzini, Adriano; Lupi, Matteo; Syafri, Ildrem; Masturyono, Rudiyanto, Ariska; Pranata, Bayu; Muzli, Widodo, Handi Sulistyo; Sudrajat, Ajat; Sugiharto, Anton


    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green's functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  4. Study of cystic artery by arteriography. Importance of previous cholecystography

    Machado, G.O.

    An oral cholecystography previously to celiac and mesenteric arteriography is performed, in order to identify the cystic artery, in 42 patients with pancreatitis, according Seldinger technique. The cystic artery was identified in all the cases, the pattern being the outlet of the cystic artery from the right hepatic artery. Infusion pump and seriography were not used.

  5. New study reveals twice as many asteroids as previously believed


    The ISO satellite Credits: ESA ISO An artist's impression of the ISO spacecraft. The ISO Deep Asteroid Search indicates that there are between 1.1 million and 1.9 million 'space rocks' larger than 1 kilometre in diameter in the so-called 'main asteroid belt', about twice as many as previously believed. However, astronomers think it is premature to revise current assessments of the risk of the Earth being hit by an asteroid. Despite being in our own Solar System, asteroids can be more difficult to study than very distant galaxies. With sizes of up to one thousand kilometres in diameter, the brightness of these rocky objects may vary considerably in just a few minutes. They move very quickly with respect to the stars - they have been dubbed 'vermin of the sky' because they often appear as trails on long exposure images. This elusiveness explains why their actual number and size distribution remains uncertain. Most of the almost 40,000 asteroids catalogued so far (1) orbit the Sun forming the 'main asteroid belt', between Mars and Jupiter, too far to pose any threat to Earth. However, space-watchers do keep a closer eye on another category of asteroids, the 'Near Earth Asteroids' or 'NEAs', which are those whose orbits cross, or are likely to cross, that of our planet. The ISO Deep Asteroid Search (IDAS), the first systematic search for these objects performed in infrared light, focused on main belt asteroids. Because it is impossible to simply point the telescope at the whole main belt and count, astronomers choose selected regions of the belt and then use a theoretical model to extrapolate the data to the whole belt. Edward Tedesco (TerraSystems, Inc., New Hampshire, United States) and François-Xavier Desert (Observatoire de Grenoble, France) observed their main belt selected areas in 1996 and 1997 with ESA's ISO. They found that in the middle region of the belt the density of asteroids was 160 asteroids larger than 1 kilometre per square degree - an area of the

  6. Study on Seismicity of Sino-Mongolia Arc Areas

    Xu, Guangyin; Wang, Suyun


    Using the earthquake catalogue from China, Mongolia and the global catalogue, the uniform catalogue of North China, Mongolia and adjacent areas, which is within the region 80-130°E, 40-55°N, has been established by Institute of Geophysics, China Earthquake Administration and Research Center of Astronomy and Geophysics, Mongolian Academy of Science for the seismic hazard analysis and seismic zoning map of Mongolia according to the following principles. 1) Earthquakes, which just exist in one catalogue, need to be verified further. If the earthquakes occurred in the country where the catalog comes from, then they will be adopted. If not, it should be checked with other more data. 2) The events that come from the three data sources have be checked and verified as followings. (1) The parameters of earthquakes that occurred in China will be taken from China catalog. (2)The parameters of earthquakes that occurred in Mongolia will be taken from Mongolia catalog. (3) The parameters of earthquakes that occurred in the adjacent areas will be taken from the global catalog by Song et al. According to the uniform catalogue, the seismicity of the North China, Mongolia and adjacent areas is analyzed, and the conclusions as followings are made. 1) The epicenter map can be roughly divided into two parts, bounded by the longitude line 105°E , in accordance with the "North-South Seismic Belt" of China. The seismicity is in a high level with many strong earthquakes in the west and is in a low level with little strong events in the east. 2) Most earthquakes are shallow-focus events, but there are also several middle or deep-focus events in the study area. 3) Earthquakes with magnitude greater than 5 are basically complete since 1450 A.D., and the seismicity of the study areas is in a high level since 1700 A. 4) Two seismic belts, Altay seismic belt and Bolnay-Baikal seismic belt, are determined according to the epicenters and tectonics. 5) The b-values of magnitude - frequency

  7. Vertical seismic profiling and integration with reflection seismic studies at Laxemar, 2000

    Juhlin, C.; Bergman, B. [Uppsala Univ. (Sweden); Cosma, C.; Keskinen, J.; Enescu, N. [Vibrometric Oy, Helsinki (Finland)


    Vertical seismic profile (VSP) data were acquired in October 2000 in the 1700 m deep KLX02 borehole, near Laxemar in southeastern Sweden. The objectives of the VSP were to image reflectors in the borehole for correlation with surface seismic and borehole data, study the signal penetration of explosive versus mechanical sources and determine the seismic velocity as a function of depth. Five principal source points were used, one located close to the KLX02 wellhead and 4 others that were offset by about 200 m to 400 m. An explosive source was only used at the wellhead and consisted of 15 grams of dynamite in 90 cm deep shot holes in bedrock. A swept impact seismic source (SIST) was also used at the wellhead, as well as at the other four offset source points. The primary SIST source consisted of a computer controlled mechanical hammer mounted on a tractor. By activating the hammer over a 15 second sweep length, the total energy transferred to the ground is on the same order as that produced by the dynamite. The recorded data are then processed to generate seismic records that are equivalent to a single impact source. A smaller hand held SIST source was also tested at the wellhead. Tests of both the tractor mounted source and dynamite were made at a location offset somewhat from the wellhead at a site containing loose sediments at the surface. Full waveform sonic, resistivity and gamma logs were also acquired in conjunction the VSP survey. A comparison between the explosive and large SIST source shows that comparable energy levels are produced by the two methods. The SIST source appears to be more stable in terms of the energy level, although the frequency content of data are somewhat lower. However, its most significant advantage is the low cost of preparation of the source points and the speed of the acquisition. Numerous reflections are observed on the VSP, as is the case on the surface seismic, implying a complex structure in the vicinity of the KLX02 borehole

  8. Statistical study of seismicity associated with geothermal reservoirs in California

    Hadley, D.M.; Cavit, D.S.


    Statistical methods are outlined to separate spatially, temporally, and magnitude-dependent portions of both the random and non-random components of the seismicity. The methodology employed compares the seismicity distributions with a generalized Poisson distribution. Temporally related events are identified by the distribution of the interoccurrence times. The regions studied to date include the Imperial Valley, Coso, The Geysers, Lassen, and the San Jacinto fault. The spatial characteristics of the random and clustered components of the seismicity are diffuse and appear unsuitable for defining the areal extent of the reservoir. However, from the temporal characteristics of the seismicity associated with these regions a general discriminant was constructed that combines several physical parameters for identifying the presence of a geothermal system.

  9. Broadband Seismic Studies In Southern Asia


    the granulite terrain, the crust is both thicker (44 1 km deep) and more complicated, with a mid-crustal discontinuity at approximately 25-km depth...the granulite terrain (KOD, Fig. 1) the crust is 43 km thick. Thus, there are significant differences in Moho depth over southern India, but the...Moho there is about 5 km deeper, a result also noted in the Deep Seismic Soundings from the region. To the south of the shield in the granulite terrain


    E. A. Levina


    Full Text Available Seismicity migration is studied by a new method based on space-time diagrams and a combination of cluster and regression analyses. Data from the global and Baikal regional earthquake catalogues are analysed with the application of the specially designed geographic information system (GIS in order to establish parameters and mechanisms of seismicity migration in space and time. We study the migration of seismic events in the following geostructural systems: the Baikal rift zone (BRZ, the area between BRZ and the Indo-Eurasian interplate collision zone, the area between BRZ and the West-Pacific seismic foci Benoiff zone, and two segments of the Middle Atlantic ridge.As evidenced by the obtained results, studying regimes of seismic migration provides for analyses of space-time distribution of seismic energy in the fault-block structure of the lithosphere and facilitates more detailed studies of the origin of deformation waves and mechanisms of the seismotectonic regime of the Earth. Forward (from the equator and backward (towards the equator migration of seismic events are established in all the regions under study. It is assumed that this phenomenon may result from regular changes of the polar compression of the Earth due to variations of its rotation regime. Besides, it is revealed that energy clusters of migration are regularly generated, and the regularity may be related to the 11-year cycle of the solar activity which impacts the seismic regime. We discuss the need to study the interference of wave deformations in the lithosphere which are initiated by several external energy sources. It is proposed to consider the regimes of planetary seismicity migration as a reflection of redistribution of endogenic (primarily heat energy of the Earth during the destruction of its lithospheric shell under the impacts of cosmogenic factors via triggering mechansms. With reference to our positive experiences of applying the proposed concept to BRZ, we

  11. A seismic design of nuclear reactor building structures applying seismic isolation system in a seismicity region-a feasibility case study in Japan

    Kubo, Tetsuo [The University of Tokyo, Tokyo (Japan); Yamamoto, Tomofumi; Sato, Kunihiko [Mitsubishi Heavy Industries, Ltd., Kobe (Japan); Jimbo, Masakazu [Toshiba Corporation, Yokohama (Japan); Imaoka, Tetsuo [Hitachi-GE Nuclear Energy, Ltd., Hitachi (Japan); Umeki, Yoshito [Chubu Electric Power Co. Inc., Nagoya (Japan)


    A feasibility study on the seismic design of nuclear reactor buildings with application of a seismic isolation system is introduced. After the Hyogo-ken Nanbu earthquake in Japan of 1995, seismic isolation technologies have been widely employed for commercial buildings. Having become a mature technology, seismic isolation systems can be applied to NPP facilities in areas of high seismicity. Two reactor buildings are discussed, representing the PWR and BWR buildings in Japan, and the application of seismic isolation systems is discussed. The isolation system employing rubber bearings with a lead plug positioned (LRB) is examined. Through a series of seismic response analyses using the so-named standard design earthquake motions covering the design basis earthquake motions obtained for NPP sites in Japan, the responses of the seismic isolated reactor buildings are evaluated. It is revealed that for the building structures examined herein: (1) the responses of both isolated buildings and isolating LRBs fulfill the specified design criteria; (2) the responses obtained for the isolating LRBs first reach the ultimate condition when intensity of motion is 2.0 to 2.5 times as large as that of the design-basis; and (3) the responses of isolated reactor building fall below the range of the prescribed criteria.

  12. Review of seismicity and ground motion studies related to development of seismic design at SRS

    Stephenson, D.E. [Westinghouse Savannah River Co., Aiken, SC (United States); Acree, J.R. [Westinghouse Environmental and Geotechnical Services, Inc., Columbia, SC (United States)


    The NRC response spectra developed in Reg. Guide 1.60 is being used in the studies related to restarting of the existing Savannah River Site (SRS) reactors. Because it envelopes all the other site specific spectra which have been developed for SRS, it provides significant conservatism in the design and analysis of the reactor systems for ground motions of this value or with these probability levels. This spectral shape is also the shape used for the design of the recently licensed Vogtle Nuclear Station, located south of the Savannah River from the SRS. This report provides a summary of the data base used to develop the design basis earthquake. This includes the seismicity, rates of occurrence, magnitudes, and attenuation relationships. A summary is provided for the studies performed and methodologies used to establish the design basis earthquake for SRS. The ground motion response spectra developed from the various studies are also summarized. The seismic hazard and PGA`s developed for other critical facilities in the region are discussed, and the SRS seismic instrumentation is presented. The programs for resolving outstanding issues are discussed and conclusions are presented.

  13. Treatment of kappa in Recent Western US Seismic Nuclear Plant Probabilistic Seismic Hazard Studies

    Toro, G. R.; Di Alessandro, C.; Al Atik, L.


    The three operating nuclear plants (Diablo Canyon, Palo Verde, and Columbia Generating Station) in the western United States recently performed SSHAC Level 3 seismic hazard studies in response to a Request for Information by the Nuclear Regulatory Commission, following the accident at the Fukushima Dai-ichi nuclear facility. The treatment of zero-distance kappa, referred to as kappa_0 and commonly attributed to material damping and scattering in the shallow crust, was given extensive consideration in these studies. Available ground motion prediction equations (GMPEs) do not typically include kappa_0 as a prediction parameter and are developed for an average kappa_0 of the host region. Kappa scaling is routinely applied to adjust for the differences in average kappa between the GMPEs host regions and the target regions. The impact of kappa scaling on the results of probabilistic seismic hazard analyses is significant for nuclear and other facilities that are sensitive to high frequency ground motions (frequencies greater than about 10 Hz). There are several available approaches for deriving kappa scaling factors to GMPEs, which all require estimating kappa_0 at the target site. It is difficult to constrain the target kappa_0 empirically due to the scarcity of ground-motion data from hard-rock sites in ground-motion databases.The hazard studies for the three nuclear power plants had different data, faced different challenges in the estimation of kappa_0, and used different methods for the estimation of the effect of kappa_0 on the site-specific ground motions. This presentation summarizes the approaches used for the evaluation of kappa_0 and for their incorporation in the probabilistic seismic hazard analysis. Emphasis is given to the quantification of the kappa_0 uncertainty, and on the evaluation of its impact to the resulting seismic hazard at the different sites.

  14. Long term study of the seismic environment at LIGO

    Daw, E J; Lormand, D; Lubinski, M; Zweizig, J


    The LIGO experiment aims to detect and study gravitational waves using ground based laser interferometry. A critical factor to the performance of the interferometers, and a major consideration in the design of possible future upgrades, is isolation of the interferometer optics from seismic noise. We present the results of a detailed program of measurements of the seismic environment surrounding the LIGO interferometers. We describe the experimental configuration used to collect the data, which was acquired over a 613 day period. The measurements focused on the frequency range 0.1-10 Hz, in which the secondary microseismic peak and noise due to human activity in the vicinity of the detectors was found to be particularly critical to interferometer performance. We compare the statistical distribution of the data sets from the two interferometer sites, construct amplitude spectral densities of seismic noise amplitude fluctuations with periods of up to 3 months, and analyze the data for any long term trends in the...


    S. V. Popov


    Full Text Available The results of the remote sensing which carried out in the LakeVostokarea are discussed in the paper. A.P. Kapitsa and O.G. Sorokhtin started the geophysical researches in this area in 1950s. Satellite altimetry data, which analyzed in 1990s yielded to the discovering of the LakeVostok. After that, PMGE and RAE started the systematic studying of this natural phenomenon by seismic and radio-echo sounding. Total, 318 seismic soundings and 5190 kmof the radio-echo profiles has been collected by 2008. Special precise measurements which carried out in the 5G-1 borehole vicinity are resulted in the ice thickness over Vostok Station is 3760±30 mby seismic and 3775±15 mby radio-echo sounding. Thus, the error of geophysical measurements is less than 0.3%. The Russian investigations are resulted in definition the border of the lake, the discovering of 56 subglacial water caves around the lake and compilation the maps including ice thickness, ice base and bedrock topography and the depth of the lake. Average depth of the LakeVostokis about 400 m; water volume is 6100 km3. After 2008, the remote sensing works have been concentrated to the studying of the bottom sediments by refraction seismic technique. The firsts result shown that the bottom sediments thickness varies from 400 to1200 m.

  16. The application of refraction seismics in alpine permafrost studies

    Draebing, Daniel


    Permafrost studies in alpine environments focus on landslides from permafrost-affected rockwalls, landslide deposits or periglacial sediment dynamics. Mechanical properties of soils or rocks are influenced by permafrost and changed strength properties affect these periglacial processes. To assess the effects of permafrost thaw and degradation, monitoring techniques for permafrost distribution and active-layer thaw are required. Seismic wave velocities are sensitive to freezing and, therefore, refraction seismics presents a valuable tool to investigate permafrost in alpine environments. In this study, (1) laboratory and field applications of refraction seismics in alpine environments are reviewed and (2) data are used to quantify effects of rock properties (e.g. lithology, porosity, anisotropy, saturation) on p-wave velocities. In the next step, (3) influence of environmental factors are evaluated and conclusions drawn on permafrost differentiation within alpine periglacial landforms. This study shows that p-wave velocity increase is susceptible to porosity which is pronounced in high-porosity rocks. In low-porosity rocks, p-wave velocity increase is controlled by anisotropy decrease due to ice pressure (Draebing and Krautblatter, 2012) which enables active-layer and permafrost differentiation at rockwall scale (Krautblatter and Draebing, 2014; Draebing et al., 2016). However, discontinuity distribution can result in high anisotropy effects on seismic velocities which can impede permafrost differentiation (Phillips et al., 2016). Due to production or deposition history, porosity can show large spatial differences in deposited landforms. Landforms with large boulders such as rock glaciers and moraines show highest p-wave velocity differences between active-layer and permafrost which facilitates differentiation (Draebing, 2016). Saturation with water is essential for the successful application of refraction seismics for permafrost detection and can be controlled at

  17. A study of seismic wave propagation in heterogeneous crust

    Akerberg, Peeter Michael

    Three different aspects of estimating properties from seismic data are treated in this thesis: (1) Deterministic processing of a high resolution shallow seismic data set with good geologic control, (2) traveltime estimation from complicated models described statistically, and (3) estimation of a the vertical autocorrelation length of such models. The first part of this thesis is the processing and interpretation of a shallow seismic dataset collected in an open pit copper mine near Tyrone, New Mexico. The seismic image is compared with the outcrop in the open pit mine wall along which the seismic line was collected, and with drill data obtained from the mine operators. Specific features imaged by the experiment include the base of the overlaying sediment, the base of the leached capping, and fractures and shear zones that control local ground water flow. The features in the migrated section compare well with outcrop and drill data. The second part of the thesis studies the systematic bias of velocities estimated from first arrival travel times measured from a class of very complicated velocity models. Traveltimes were computed for statistically described velocity models with anisotropic von Karman correlation functions. The results of a finite difference eikonal solver, corresponding to very small wavelength experiments, are compared to results from picking first arrivals of full wavefield finite difference simulations. The eikonal solver results show the largest systematic bias, corresponding to the ray theoretical limit, and the results from the full wavefield experiments are smaller, but with very similar dependence on aspect ratio of the anisotropic correlation function. The third part defines two methods to obtain the vertical correlation length from seismic data approximated by the primary reflectivity series, which conventionally is used as the ideal result of seismic imaging. The first method is based on fitting a theoretical power spectrum based on the

  18. Seismic vulnerability study Los Alamos Meson Physics Facility (LAMPF)

    Salmon, M. [EQE International, Inc., Irvine, CA (United States); Goen, L.K. [Los Alamos National Lab., NM (United States)


    The Los Alamos Meson Physics Facility (LAMPF), located at TA-53 of Los Alamos National Laboratory (LANL), features an 800 MeV proton accelerator used for nuclear physics and materials science research. As part of the implementation of DOE Order 5480.25 and in preparation for DOE Order 5480.28, a seismic vulnerability study of the structures, systems, and components (SSCs) supporting the beam line from the accelerator building through to the ends of die various beam stops at LAMPF has been performed. The study was accomplished using the SQUG GIP methodology to assess the capability of the various SSCs to resist an evaluation basis earthquake. The evaluation basis earthquake was selected from site specific seismic hazard studies. The goals for the study were as follows: (1) identify SSCs which are vulnerable to seismic loads; and (2) ensure that those SSCs screened during die evaluation met the performance goals required for DOE Order 5480.28. The first goal was obtained by applying the SQUG GIP methodology to those SSCS represented in the experience data base. For those SSCs not represented in the data base, information was gathered and a significant amount of engineering judgment applied to determine whether to screen the SSC or to classify it as an outlier. To assure the performance goals required by DOE Order 5480.28 are met, modifications to the SQUG GIP methodology proposed by Salmon and Kennedy were used. The results of this study ire presented in this paper.

  19. Some preliminary results of a worldwide seismicity estimation: a case study of seismic hazard evaluation in South America

    C. V. Christova


    Full Text Available Global data have been widely used for seismicity and seismic hazard assessment by seismologists. In the present study we evaluate worldwide seismicity in terms of maps of maximum observed magnitude (Mmax, seismic moment (M 0 and seismic moment rate (M 0S. The data set used consists of a complete and homogeneous global catalogue of shallow (h £ 60 km earthquakes of magnitude MS ³ 5.5 for the time period 1894-1992. In order to construct maps of seismicity and seismic hazard the parameters a and b derived from the magnitude-frequency relationship were estimated by both: a the least squares, and b the maximum likelihood, methods. The values of a and b were determined considering circles centered at each grid point 1° (of a mesh 1° ´1° and of varying radius, which starts from 30 km and moves with a step of 10 km. Only a and b values which fulfill some predefined conditions were considered in the further procedure for evaluating the seismic hazard maps. The obtained worldwide M max distribution in general delineates the contours of the plate boundaries. The highest values of M max observed are along the circum-Pacific belt and in the Himalayan area. The subduction plate boundaries are characterized by the largest amount of M 0 , while areas of continental collision are next. The highest values of seismic moment rate (per 1 year and per equal area of 10 000 km 2 are found in the Southern Himalayas. The western coasts of U.S.A., Northwestern Canada and Alaska, the Indian Ocean and the eastern rift of Africa are characterized by high values of M 0 , while most of the Pacific subduction zones have lower values of seismic moment rate. Finally we analyzed the seismic hazard in South America comparing the predicted by the NUVEL1 model convergence slip rate between Nazca and South America plates with the average slip rate due to earthquakes. This consideration allows for distinguishing between zones of high and low coupling along the studied convergence

  20. Present Status of Historical Seismicity Studies in Colombia and Venezuela

    Sarabia, A.; Cifuentes, H.; Altez Ortega, R.; Palme, C.; Dimate, C.


    After the publication of the SISRA (CERESIS-1985) regional project, a unified catalog of seismic parameters and intensities for South America, researchers in historical seismicity have continued advancing on different scales in the area of this study of seismic hazard. The most important initiatives carried out in this area in Colombia and Venezuela can be grouped as follows: a) Reviews of destructive earthquakes in national and international historic archives, principally by Altez and FUNVISIS in Venezuela and Espinosa, Salcedo, and Sarabia et al in Colombia, leading to the preparation of seismologic catalogues, scientific and dissemination articles, reports, books, among others. b) Organization and systematization of historic information to develop public domain data bases and information, specifically the Historic Seismologic Teleinformation System in Venezuela, carried out between 2004 and 2008 under the coordination of Christl Palme and accessible on-line: As well, the "Historia Sísmica de Colombia 1550-1830" (Seismic History in Colombia 1550-1830) data base, in CD-ROM, by Espinosa Baquero (2003) and the historic seismicity information system of Colombia (Servicio Geológico Colombiano-Universidad Nacional de Colombia), published on the internet in 2012: c) Macroseismic studies for the development of intensity attenuation equations and the quantification and revaluation of basic historic earthquake parameters using isoseismal maps (Rengifo et al., Palme et al., Salcedo et al., among others) and procedures such as Boxer and Bakun & Wentworth (Palme et al., Dimaté, among others), which have produced significant changes in the parameters of some of the large earthquakes. d) Symposiums of researchers to promote interest and development in the discipline, including Jornadas Venezolanas de Sismología Histórica (Venezuelan Congress of Historical Seismology), held

  1. Parametric study of cantilever walls subjected to seismic loading

    Comina, Cesare; Corigliano, Mirko; Foti, Sebastiano; Lai, Carlo G.; Lancellotta, Renato; Leuzzi, Francesco; Nicosia, Giovanni Li Destri; Paolucci, Roberto; Pettiti, Alberto; Psarropoulos, Prodromos N.; Zanoli, Omar


    The design of flexible earth retaining structures under seismic loading is a challenging geotechnical problem, the dynamic soil-structure interaction being of paramount importance for this kind of structures. Pseudo-static approaches are often adopted but do not allow a realistic assessment of the performance of the structure subjected to the seismic motions. The present paper illustrates a numerical parametric study aimed at estimating the influence of the dynamic soil-structure interaction in the design. A series of flexible earth retaining walls have been preliminary designed according to the requirements of Eurocode 7 and Eurocode 8—Part 5; their dynamic behaviour has been then evaluated by means of dynamic numerical simulations in terms of bending moments, accelerations and stress state. The results obtained from dynamic analyses have then been compared with those determined using the pseudo-static approach.

  2. A Preliminary Feasibility Study On Seismic Monitoring Of Polymer Flooding

    Nguyen, P. K.; Park, C.; Lim, B.; Nam, M.


    Polymer flooding using water with soluble polymers is an enhanced oil recovery technique, which intends to maximize oil-recovery sweep efficiency by minimizing fingering effects and as a result creating a smooth flood front; polymer flooding decreases the flow rates within high permeability zone while enhances those of lower permeabilities. Understanding of fluid fronts and saturations is critical to not only optimizing polymer flooding but also monitoring the efficiency. Polymer flooding monitoring can be made in single well scale with high-resolution wireline logging, in inter-well scale with tomography, and in reservoir scale with surface survey. For reservoir scale monitoring, this study makes a preliminary feasibility study based on constructing rock physics models (RPMs), which can bridge variations in reservoir parameters to the changes in seismic responses. For constructing RPMs, we change reservoir parameters with consideration of polymer flooding to a reservoir. Time-lapse seismic data for corresponding RPMs are simulated using a time-domain staggered-finite-difference modeling with implementation of a boundary condition of conventional perfect match layer. Analysis on time-lapse seismic data with respect to the changes in fluid front and saturation can give an insight on feasibility of surface seismic survey to polymer flooding. Acknowledgements: This work was supported by the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2012T100201588). Myung Jin Nam was partially supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST) (No. 2011-0014684).

  3. Study of rationalized safety design based on the seismic PSA for an LMFBR

    Nakai, Ryodai; Yamaguchi, Akira


    Seismic PSA was carried out for a typical liquid metal cooled fast breeder reactor (LMFBR) in order to study the rationalized seismic design, maintaining and/or improving safety during seismic event. The seismic sequence quantification identifies the dominant structures, systems and components (SSCs) to the seismic core damage frequency (CDF). The sensitivity analyses by reducing or increasing the seismic capacity for SSCs are used to examine the optimized seismic design in view of safety and economical aspects. The LMFBR-specific risk-significant SSCs are reactor coolant boundary, decay heat removal coolant path and reactor control rod, which are different from those of light water reactors (LWRs). The electrical power supply system has a minor contribution to the seismic CDF. The sensitivity study shows that passive safety features of LMFBRs are important to maintain and/or enhance seismic capacity. The passive safety includes the decay heat removal capability via natural circulation and safety measures without depending on the support systems such as alternating current (AC) electrical power, for example. On the course of seismic sequence quantification, a methodology to evaluate the probability of seismic-induced multiple failure has been developed and applied to the decay heat removal function. The results suggest the multiplicity of the triply redundant system is to be considered for the significant components such as the decay heat removal path when one considers the difference in the seismic response.

  4. A case study of hydrocarbon prospect evaluation in north Exito field by using seismic attribute and seismic inversion

    Haris, A.; Fakhri, M. K.; Isniarny, N.; Riyanto, A.


    Exito field is one of the oil fields which located in the Mahakam Delta, East Borneo. Geological structures that control in this field is a subducted anticline structure towards the north. The wells drilling in this area is only conducted in the southern part of the Exito field. This study is focused only on the interval Gamma Exito Field. This interval has the most reservoir unit and productive one. The interval Gamma is bounded on the top and the bottom marker. This study aims to interpret seismic attribute and seismic inversion. The seismic attribute that is used in this study is the root mean square (RMS) attribute. The application of this seismic attribute is carried out to see the direction of paleo sediment pattern of the reservoir. On the other hand, the seismic inversion is used to describe the porosity of the reservoir. In addition, the data from the interval Gamma dipmeter is used to validate the analysis of paleo sediment patterns. The result shows that the northern part of the Exito Fields has good prospects in terms of porosity and paleo sediment pattern.

  5. Final report of the cooperative study on seismic isolation design. The second stage

    Uryu, Mitsuru; Terada, Syuji; Shioya, Tsutomu (and others)


    The applicability of the seismic isolation design onto the nuclear fuel facilities, which must clear severe criteria of integrity, has been examined. Following the first stage of the cooperative study, conducted from 1988 to 1991, the second stage included critical vibration testing, seismic observation of seismic isolation building and founded buildings of non-isolation, with the objectives of clarifying the policies on critical design of seismic isolation building. Integrity of the seismic isolation piping system was tested by means of static deformation test, with variable inner water pressure and relative deformation. (Yamamoto, A.)

  6. Integrated seismic studies at the Rye Patch Geothermal Reservoir, Nevada

    Gritto, Roland; Daley, Thomas M.; Majer, Ernest L.


    A 3-D surface seismic reflection survey, covering an area of over 3 square miles, was conducted at the Rye Patch geothermal reservoir (Nevada) to explore the structural features that may control geothermal production in the area. In addition to the surface sources and receivers, a high-temperature three-component seismometer was deployed in a borehole at a depth of 3900 ft within the basement below the reservoir, which recorded the waves generated by all surface sources. A total of 1959 first-arrival travel times were determined out of 2134 possible traces. Two-dimensional ray tracing was performed to simulate wave propagation from the surface sources to the receiver at depth. Travel time differences between observed and calculated times were mapped to topographic changes in the elevation of the interface between the carbonate basement and the sedimentary and volcanic unit above. Results indicate the presence of two dominant geologic features. The first confirms the regional trend of the geologic units in the Basin and Range province with a north-south strike and dip to the west, as expected for normal faulting encountered in an extensional regime. The second is a local disturbance of this regional pattern in form of an elevation of the interface between the carbonate basement and the overlying sedimentary sequence, striking east-west. The geometry of the structure is corroborated by results from a seismic-reflection survey, and by results of tomographic studies conducted as part of the seismic survey. Seismic waves, generated from far-offset shots during the 3-D surface survey, exhibit a sudden decrease in amplitudes while propagating across the boundaries of the elevation high. This apparent boundary correlates spatially with the location of the Rye Patch fault as interpreted from the 3-D seismic reflection data. Finite-difference modeling of elastic wave propagation is performed to estimate the structural parameters of the fault. Questions to be answered are

  7. The Study on Information Extraction Technology of Seismic Damage

    Huang Zuo-wei


    Full Text Available In order to improve the information extraction technology of seismic damage assessment and information publishing of earthquake damage. Based on past earthquake experience it was constructed technical flow of earthquake damage assessment rapidly, this study, take Yushu earthquake as example, studies the framework and establishment of the information service system by means of Arc IMS and distributed database technology. It analysis some key technologies, build web publishing architecture of massive remote sensing images. The system implements joint application of remote sensing image processing technology, database technology and Web GIS technology, the result could provide the important basis for earthquake damage assessment, emergency management and rescue mission.

  8. Subtle trap recognition based on seismic sedimentology-A case study from Shengli Oilfield

    Huang Handong; Zhang Ruwei; Luo Qun; Zhao Di; Peng Yongmin


    Seismic sedimentology is the study of sedimentary rocks and facies using seismic data. However, often the sedimentary body features can't be described quantitatively due to the limit of seismic resolution. High resolution inversion offsets this limitation and is applied to seismic sedimentology to identify subtle traps under complex geologic conditions, thereby widening the applicable range of seismic sedimentology. In this paper, based on seismic sedimentology, seismic phase-controlled nonlinear random inversion is used to predict the sandy conglomerate reservoir of Es3 in the Chezhen depression in Shengli Oilfield. Thickness and sedimentary microfacies maps of sandy conglomerate bodies in several stages are presented and several subtle traps were predicted and verified by drilling.

  9. Slip Distribution of Two Recent Large Earthquakes in the Guerrero Segment of the Mexican Subduction Zone, and Their Relation to Previous Earthquakes, Silent Slip Events and Seismic Gaps

    Hjorleifsdottir, V.; Ji, C.; Iglesias, A.; Cruz-Atienza, V. M.; Singh, S. K.


    previous studies; farfield body- and surface-wave data, GPS displacement vectors and near field and regional strong motion records. We focus on estimating the rupture areas as well as how well constrained their limits and separations are. Finally, we discuss the implications for the friction on the fault plane and the permanency in time of the asperities.

  10. Study on the seismic performance of a double spherical seismic isolation bearing

    Peng Tianbo; Li Jianzhong; Xu Yan; Fan Lichu


    In this paper,the configuration and working mechanism of the recently developed double spherical seismic isolation (DSSI) bearing are introduced in detail.Then,vertical displacement of the DSSI bearing due to sliding on a spherical surface is analyzed.The results from seismic performance testing of the bearing are given,and a numerical analysis of a four span continuous girder bridge is performed.The numerical analysis compares the influence of three different bearing arrangement schemes on the structural seismic response,and the results show that the DSSI bearing is effective in increasing the vertical load bearing capacity,reducing the vertical displacement,and controlling the energy dissipation capacity within a certain range.

  11. Standardization of Seismic Microzonification and Probabilistic Seismic Hazard Study Considering Site Effect for Metropolitan Areas in the State of Veracruz

    Torres Morales, G. F.; Leonardo Suárez, M.; Dávalos Sotelo, R.; Castillo Aguilar, S.; Mora González, I.


    Preliminary results obtained from the project "Seismic Hazard in the State of Veracruz and Xalapa Conurbation" and "Microzonation of geological and hydrometeorological hazards for conurbations of Orizaba, Veracruz, and major sites located in the lower sub-basins: The Antigua and Jamapa" are presented. These projects were sponsored respectively by the PROMEP program and the Joint Funds CONACyT-Veracruz state government. The study consists of evaluating the probabilistic seismic hazard considering the site effect (SE) in the urban zones of cities of Xalapa and Orizaba; the site effects in this preliminary stage were incorporated through a standard format proposed in studies of microzonation and application in computer systems, which allows to optimize and condense microzonation studies of a city. This study stems from the need to know the seismic hazard (SH) in the State of Veracruz and its major cities, defining SH as the probabilistic description of exceedance of a given level of ground motion intensity (generally designated by the acceleration soil or maximum ordinate in the response spectrum of pseudo-acceleration, PGA and Sa, respectively) as a result of the action of an earthquake in the area of influence for a specified period of time. The evaluation results are presented through maps of seismic hazard exceedance rate curves and uniform hazard spectra (UHS) for different spectral ordinates and return periods, respectively.

  12. Theory and case studies on solar induced seismicity

    Duma, Gerald; Freund, Friedemann; Kosovichev, Pavel


    Huge electric current vortices are continuously generated in the Earth's lithosphere through electromagnetic induction from powerful ionospheric electric vortex currents that arise from ionization on the sun-lit side of the Earth (Chapman S. and Bartels J., 1940). The circular telluric currents in the Earth's lithosphere interact with the Earth's main magnetic field (H), building up a magnetic moment (M). According to T = [M x H] a mechanic torque (T) results from this interaction that can reach values as high as 5x10exp13 Nm (Duma G. and Ruzhin Y., 2003). We present evidence that this ionospherically induced telluric torque, which reaches deep into the lithosphere, influences the diurnal seismicity patterns in major earthquake zones as documented by earthquakes with magnitudes M ≥ 6.0. Our results confirm observations of distinct time-of-day patterns of seismic activity reported for over a century (Omori F., 1902; Conrad V., 1932 ; Shimshoni M., 1971; Duma G. and Vilardo G., 1998; Schekotov A.Yu., Molchanov O.A. and Hayakawa M., 2005) and even much earlier by Pliny the Elder, 79 A.D. A solar influence on earthquake frequency is apparent not only in diurnal patterns, but also in seasonal (e.g. Lipovics T., 2005) and decadal patterns. The effect can be validated by data recorded continuously at geomagnetic observatories, the INTERMAGNET stations (, operating on all continents. The observatories continuously record magnetic variations which arise from the telluric currents in the Earth's lithosphere. Theory and model are presented, starting from the primary source for the effect, which is the varying solar wind speed as measured by satellites. The data are provided by the OMNI 2 directory (NASA, We offer 7 case studies that deal with seismic activity patterns in the diurnal, seasonal and long term time domains for seismic zones in Asia (Japan, Taiwan, Sumatra), N-America (California), the Mid Atlantic Ridge

  13. Piedmont seismic reflection study: A program integrated with tectonics to probe the cause of eastern seismicity

    Glover, L. III; Coruh, C.; Costain, J.K.; Bollinger, G.A. (Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Geological Sciences)


    A new tectonic model of the Appalachian orogen indicates that one, not two or more, terrane boundaries is present in the Piedmont and Blue Ridge of the central and southern Appalachians. This terrane boundary is the Taconic suture, it has been transported in the allochthonous Blue Ridge/Piedmont crystalline thrust nappe, and it is repeated at the surface by faulting and folding associated with later Paleozoic orogenies. The suture passes through the lower crust and lithosphere somewhere east of Richmond. It is spatially associated with seismicity in the central Virginia seismic zone, but is not conformable with earthquake focal planes and appears to have little causal relation to their localization.

  14. Contribution to the study of historical seismicity in the Maghrebian region, Catalogue of historiacal seismicity of the Maghreb region

    Elmrabet, T.


    The seismic risk assessment in countries with moderate seismic activity is a very delicate action as well as a high priority one in land use management and urban rehabilitation. The credibility of this assessment is based mainly on the effects of destructive earthquakes whose maximum intensities become a reference for determining the level of protection. This knowledge requires a detailed study of the damage caused by major earthquakes over a long period of time. In this context, a broad scale research about past earthquakes started in the Geophysics Laboratory, now called the National Geophysics Institute (ING) within the National Center for Scientific and Technical Research in Rabat, Morocco. It supported a thorough study which included critical historical texts scattered in various local and foreign archives. The pursuit of this study, under the project called PAMERAR, which was launched in the early 80's aimed at reducing of earthquake risk in the Arab region, led us to investigate the origin of these texts according to various public and private libraries, as in Spain and France. The scientific interest in the historical seismicity in Morocco was highlighted at the beginning of the twentieth century in several reports and catalogs but with several gaps in time and space, further research was thus necessary especially to explore documents in particular from origin sources. This interest in historical archives is within the scope of understanding the natural hazards over long period to evaluate the recurrence of earthquakes. This study leads to significant results covering 11 centuries, from AD 846 to the present. We continued to study the effects of recent earthquakes on humans and buildings heritage, this work has led to a study in the footsteps of local seismic culture. Since earthquakes do not recognize the limits of political geography, since 1993 we have undertaken to extend the research to include the entire Maghreb region. We then used the database

  15. Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies

    Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.


    This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

  16. A Study Of Fluid Pressure Migration Within The North-Central Oklahoma Seismic Gap

    Lambert, C.; Keranen, K. M.; Sickbert, T.


    The rise in seismicity in Oklahoma since 2008 provides an unusual opportunity to study fluid migration and the interaction of fluids with faults. One unique area in north-central Oklahoma is a current seismic gap between large clusters in northern and central Oklahoma, providing a window into the temporal evolution of local seismicity. The gap in seismicity occurs across the NNE-SSW trending Nemaha uplift, with long faults relatively well-oriented in the regional stress field. Wastewater disposal occurs both within and on either side of the gap, and seismicity approached both sides of the uplift in 2014. To record seismicity and seismic migration through time within the uplift and along the bounding faults on either side, we deployed a ten station array of broadband sensors in April 2015. Our goal is to detect possible seismic signals related to fluid pressure migration and to ultimately increase our understanding of the fault response to perturbations in fluid pressure. Here we present local earthquake locations from the first months of data and initial focal mechanisms. We detect higher numbers of earthquakes happening within the Nemaha uplift than recorded in existing catalogs. The seismicity is typically events. This pattern of seismicity may represent deformation on small faults as the pressure perturbation migrates into the Nemaha uplift from either side and away from wells within the uplift.

  17. Seismicity change revealed by ETAS, PI, and Z-value methods: A case study of the 2013 Nantou, Taiwan earthquake

    Kawamura, Masashi; Chen, Chien-chih; Wu, Yih-Min


    On Mar. 27, 2013, a ML6.2 earthquake occurred in the Nantou area of central Taiwan, which caused one death and nearly 90 injured. Two months later, another ML6.3 earthquake struck the same region on June 2, 2013, the epicenter of which is close to the March ML6.2 earthquake. Seismicity is a sensitive indicator of stress rate and inelastic deformation process in crust. Therefore, examination of temporal changes in seismicity is important to understand the preparatory processes of damaging inland earthquakes. In this study, we applied the Epidemic-Type Aftershock-Sequences model (ETAS model) to the earthquake data covering broader Taiwan region, which is maintained by the Central Weather Bureau (CWB) of Taiwan, to investigate precursory temporal changes in seismicity for the ML6.2 Nantou earthquake. We regard the March ML6.2 and June ML6.3 earthquakes as an event sequence and especially focus on temporal changes in seismicity prior to the ML6.2 event. Application of more than one model to an earthquake catalog would be informative in elucidating the relationships between seismicity precursors and the preparatory processes of large earthquakes. Based on this motivation, we further applied two different approaches: the pattern informatics (PI) method and the ZMAP method, which is a gridding technique based on the standard deviate (Z-value) test to the same earthquake data of CWB. As a result, we found that the epicenter of the 2013 ML6.2 Nantou earthquake was surrounded by three main seismic quiescence regions prior to its occurrence. The assumption that this is due to precursory slip (stress drop) on fault plane or its deeper extent of the ML6.2 Nantou earthquake is supported by previous researches based on seismicity data, geodedic data, and numerical simulations using rate- and state-dependent friction laws.

  18. Study on Uncertainties of Seismicity Parameters b and v4 in Seismic Statistical Zones


    For several seismic statistical zones in North China, the key factors causing uncertainties in the important seismicity parameters b and v4 and the features of their uncertainties are discussed in this paper. The magnitude of uncertainty is also analyzed. It can be seen that the key influencing factors are statistical period, methods of processing statistical samples, lower limit magnitude and the annual average occurrence ratio of large earthquakes. The variation ranges of b and v4 in the Tancheng-Lujiang zone are as high as 0.2 and 1.4 respectively, which are similar to those in the Fenwei zone. They are much smaller however in the Hebei zone because of its sufficient statistical samples.

  19. A study on the seismic fortification level of offshore platform in Bohai Sea of China

    Lu, Y.


    The Chinese sea areas are important places of offshore petroleum resources, and at the same time they are also seismically active regions. Fixed offshore platforms (OPs) are the fundamental facilities for marine resource exploitation, and usually situated in a complex and severe environment as having to endure many environmental loads in their life span, therefore, the damage to their structures may result in serious disasters. Among these environmental loads the seismic load has tremendous destructive effect and is not predictable. In case of not overly severe wind, wave and current, seismic resistance dominates the strength design of platforms. Furthermore, strong earthquakes have occurred recently or in the history of all the sea areas of oil/gas exploitation in China. Therefore, seismic design of fixed OPs is a very important issue. With the development of marine exploration and earthquake researches in the sea area, extensive studies on the seismotectonic environment and seismicity characteristics of the sea areas of China have been performed, meanwhile, more and more experience and data have been accumulated from OP design practice, which laid a foundation for studying and establishing the seismic design standard of OPs. This paper first gives an overall understanding of the seismic environment of the sea areas of China, then taking the Bohai Sea seismic risk study as an example, introducing a so-called shape factor K to characterize the seismic risk distribution in sub-regions of the Bohai Sea. Based on the seismic design ground motions for 46 platforms in Bohai Sea, a statistic analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method, a scheme of two seismic design levels is proposed, and two seismic design objectives are established respectively for the strength level earthquake and ductility level earthquake. By analogy with and comparison to the Chinese

  20. Probabilistic Completeness Studies of the INGV Seismic Network in Italy

    Schorlemmer, D.; Mele, F.; Marzocchi, W.


    An important characteristic of any seismic network is its detection completeness, which should be considered a function of space and time. Many researchers rely on robust estimates of detection completeness, especially when investigating statistical parameters of earthquake occurence. We apply the newly developed probabilistic magnitude of completeness (PMC) method to the INGV network in Italy and report on completeness and earthquake detection capabilities. We have (1) investigated the variation of detection completeness with time over the last two years, (2) conducted scenario computations on possible system failures, (3) estimated the completeness drops due to random failures of stations. The results show that the INGV network is largely stable and strongly affected only by large-scale station outages. This stability indicates that Italy can provide the data of required quality for CSEP (Collaboratory for the Study of Earthquake Predictability) testing.

  1. Seismic studies of the San Francisco-Oakland Bay Bridge

    Astaneh-Asl, A; Larsen, S; McCallen, D


    Computational simulation plays a central role in the engineering analysis and design of major bridge structures and accurate simulations are essential for the development of earthquake resistant and economical structural designs. This paper describes new methodologies and computational tools which have recently been developed for simulating earthquake ground motions and the seismic response of cable supported bridges. The simulation tools are described and an example application for an important long-span suspension bridge is demonstrated. The application portion of the study has particular focus on the potential damaging effects of long period displacement pulses and permanent ground displacements which can occur when a bridge is located in the near-field of a major earthquake fault.

  2. The impact of previous traumatic brain injury on health and functioning: a TRACK-TBI study.

    Dams-O'Connor, Kristen; Spielman, Lisa; Singh, Ayushi; Gordon, Wayne A; Lingsma, Hester F; Maas, Andrew I R; Manley, Geoffrey T; Mukherjee, Pratik; Okonkwo, David O; Puccio, Ava M; Schnyer, David M; Valadka, Alex B; Yue, John K; Yuh, Esther L


    The idea that multiple traumatic brain injury (TBI) can have a cumulative detrimental effect on functioning is widely accepted. Most research supporting this idea comes from athlete samples, and it is not known whether remote history of previous TBI affects functioning after subsequent TBI in community-based samples. This study investigates whether a previous history of TBI with loss of consciousness (LOC) is associated with worse health and functioning in a sample of individuals who require emergency department care for current TBI. Twenty-three percent of the 586 individuals with current TBI in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury study reported having sustained a previous TBI with LOC. Individuals with previous TBI were more likely to be unemployed (χ(2)=17.86; p=0.000), report a variety of chronic medical and psychiatric conditions (4.75≤χ(2)≥24.16; pTBI history. Those with a previous TBI had less-severe acute injuries, but experienced worse outcomes at 6-month follow-up. Results of a series of regression analyses controlling for demographics and acute injury severity indicated that individuals with previous TBI reported more mood symptoms, more postconcussive symptoms, lower life satisfaction, and had slower processing speed and poorer verbal learning, compared to those with no previous TBI history. These findings suggest that history of TBI with LOC may have important implications for health and psychological functioning after TBI in community-based samples.

  3. Reflection seismic studies in the Forsmark area - stage 1

    Juhlin, Christopher; Bergman Bjoern; Palm, Hans [Uppsala Univ. (Sweden). Dept. of Earth Sciences


    Reflection seismic data were acquired in the Spring of 2002 in the Forsmark area, located about 70 km northeast of Uppsala, Sweden. The Forsmark area has been targeted by SKB as a possible storage site for high level radioactive waste. About 16 km of high resolution seismic data were acquired along five separate profiles varying in length from 2 to 5 km. Non-final source and receiver spacing was 10 m with 100 active channels when recording data from a dynamite source (15-75 g). The profiles were located within a relatively undeformed lens of bedrock that trends in the NW-SE direction. The lens is surrounded by highly deformed rock on all sides. In conjunction with the reflection component of the study, all shots were also recorded on up to eleven 3-component fixed Orion seismographs. These recordings provided long offset data from which a velocity model of the uppermost 400 m of bedrock could be derived. Results from the study show that the bedrock has been well imaged down to depths of at least 3 km. The upper 1000 m of bedrock is much more reflective in the southeastern portion of the lens compared to the northwestern part close to the Forsmark reactors. This is interpreted as the bedrock being more homogeneous in the northwest. However, a major reflective zone (the A1 reflector) is interpreted to dip to the S-SE below this homogeneous bedrock. In the southeastern portion of the lens the orientation of the reflectors is well determined where the profiles cross one another. The general strike of the major reflectors is NE-SW with dips of 20-35 degrees to the southeast.

  4. Seismic noise study for a new seismic station at King Fahd University of Petroleum and Minerals in Saudi Arabia

    Kaka, S. I.


    We have carried out a seismic noise study in order to understand the noise level at three selected locations at King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia. The main purpose is to select a suitable site with low seismic noise and good signal-to-noise ratio for our new broadband seismic station. There are several factors involved in the selection of a site location for a new station. Most importantly, we need to strike a balance between a logistically convenient site versus a technically suitable site. As a starting point, we selected six potential sites due to accessibility and proximity to the seismic processing center laboratory in the Department of Earth Sciences (ESD) at KFUPM. We then eliminated two sites that are relatively close to possible low-frequency noise sources. We have considered many possible noise sources which include: vehicle traffic / heavy machinery, the direct path of air flowing from air conditioning vent, tall trees / power poles and metal doorways. One more site was eliminated because the site was located in the open where it experiences maximum wind speed which is considered a major source of noise. All three potential sites are situated within the Dammam Dome where both lower middle and upper Rus Formations are exposed. The upper Rus is mainly made up of fine grained chalky limestone and the lower Rus is made up of alternation of marls and thin dolomitic limestone. The area is not known for any major faults and considered very low seismicity and hence the identification of seismoteconic features is not required. Before conducting the noise study, we calibrated and tested the seismic recording system, which was recently acquired by the ESD at KFUPM. The system includes a seismic recorder and a sensor with a GPS device. We deployed the system in order to measure the low-frequency background noise. Knowing the low frequency noise will help in predicting the high-frequency noise. The recording systems were

  5. Coordinated study of non-seismic and weak seismic events (magnitude M less than 5) using VLF radio links

    Wolbang, Daniel; Biernat, Helfried K.; Friedrich, Martin; Schwingenschuh, Konrad; Besser, B. P.; Eichelberger, Hans; Prattes, Gustav; Rozhnoi, Alexander; Solovieva, Maria; Biagi, Pier Francesco; Boudjada, Mohammed Y.

    In this study we analyze low seismicity earthquakes (EQs) with magnitudes M earthquake precursor phenomena generated in the lithosphere and then propagating in the atmosphere / ionosphere [1]. The major challenge of this seismo-electromagnetic (SEM) method is to differentiate parameter variations and disentangle seismic from non-seismic sources. In the course of the European radio receiver network (International Network for Frontier Research on Earthquake Precursors, INFREP) radio signals in the VLF/LF frequency range are continuously recorded by dedicated, distributed transmitters. The major VLF receiving station for this study (10-50 kHz, Graz, Austria) operates continuously throughout the year, the selected network-wide temporal resolution is 20 sec, 12 transmitters, located mainly in Europe, are received (amplitude and phase). The facility has a proven high reliability and availability. The VLF links from the transmitters to the receivers are sometimes more, sometimes less influenced by various disturbances. In case the signal is crossing an EQ preparation zone, we are in principle able to detect seismic activity if the signal to noise ratio is high enough [2]. Generally we distinguish between ionospheric or atmospheric disturbances, influences which depend on the EQ properties, and transmitter variations itself. Ionospheric / Atmospheric variations can be generated, e.g. by geomagnetic storms, solar flares or waves in the troposphere. The properties of the sub-ionospheric VLF waveguide are affected by the length of the radio path, the distance to the EQ preparation zone, the parameters of the earthquake (magnitude, depth, type), and daytime / nighttime disturbances. In order to minimize ionospheric influences on the radio path we are considering mainly nighttime periods. Beside the terminator time method, where only the VLF sunrise and sunset period is analyzed, we are using the residual method (2 hours before and after local midnight), where the difference

  6. Matched cohort study of external cephalic version in women with previous cesarean delivery.

    Keepanasseril, Anish; Anand, Keerthana; Soundara Raghavan, Subrahmanian


    To evaluate the efficacy and safety of external cephalic version (ECV) among women with previous cesarean delivery. A retrospective study was conducted using data for women with previous cesarean delivery and breech presentation who underwent ECV at or after 36 weeks of pregnancy during 2011-2016. For every case, two multiparous women without previous cesarean delivery who underwent ECV and were matched for age and pregnancy duration were included. Characteristics and outcomes were compared between groups. ECV was successful for 32 (84.2%) of 38 women with previous cesarean delivery and 62 (81.6%) in the control group (P=0.728). Multivariate regression analysis confirmed that previous cesarean was not associated with ECV success (odds ratio 1.89, 95% confidence interval 0.19-18.47; P=0.244). Successful vaginal delivery after successful ECV was reported for 19 (59.4%) women in the previous cesarean delivery group and 52 (83.9%) in the control group (Pcesarean delivery. To avoid a repeat cesarean delivery, ECV can be offered to women with breech presentation and previous cesarean delivery who are otherwise eligible for a trial of labor. © 2017 International Federation of Gynecology and Obstetrics.

  7. Video-Seismic coupling for debris flow study at Merapi Volcano, Indonesia

    Budi Wibowo, Sandy; Lavigne, Franck; Mourot, Philippe; Sukatja, Bambang


    Previous lahar disasters caused at least 44.252 death toll worldwide from 1600 to 2010 of which 52 % was due to a single event in the late 20th century. The need of a better understanding of lahar flow behavior makes general public and stakeholders much more curious than before. However, the dynamics of lahar in motion is still poorly understood because data acquisition of active flows is difficult. This research presents debris-flow-type lahar on February 28, 2014 at Merapi volcano in Indonesia. The lahar dynamics was studied in the frame of the SEDIMER Project (Sediment-related Disasters following the 2010 centennial eruption of Merapi Volcano, Java, Indonesia) based on coupling between video and seismic data analysis. We installed a seismic station at Gendol river (1090 meters asl, 4.6 km south from the summit) consisting of two geophones placed 76 meters apart parallel to the river, a high definition camera on the edge of the river and two raingauges at east and west side of the river. The results showed that the behavior of this lahar changed continuously during the event. The lahar front moved at an average speed of 4.1 m/s at the observation site. Its maximum velocity reached 14.5 m/s with a peak discharge of 473 m3/s. The maximum depth of the flow reached 7 m. Almost 600 blocks of more than 1 m main axis were identified on the surface of the lahar during 36 minutes, which represents an average block discharge of 17 blocks per minute. Seismic frequency ranged from 10 to 150 Hz. However, there was a clear difference between upstream and downstream seismic characteristics. The interpretation related to this difference could be improved by the results of analysis of video recordings, especially to differentiate the debris flow and hyperconcentrated flow phase. The lahar video is accessible online to the broader community ( Keywords: lahar, video, seismic signal, debris flow, hyperconcentrated flow, Merapi, Indonesia.

  8. Seismic imaging of post-glacial sediments - test study before Spitsbergen expedition

    Szalas, Joanna; Grzyb, Jaroslaw; Majdanski, Mariusz


    This work presents results of the analysis of reflection seismic data acquired from testing area in central Poland. For this experiment we used total number of 147 vertical component seismic stations (DATA-CUBE and Reftek "Texan") with accelerated weight drop (PEG-40). The profile was 350 metres long. It is a part of pilot study for future research project on Spitsbergen. The purpose of the study is to recognise the characteristics of seismic response of post-glacial sediments in order to design the most adequate survey acquisition parameters and processing sequence for data from Spitsbergen. Multiple tests and comparisons have been performed to obtain the best possible quality of seismic image. In this research we examine the influence of receiver interval size, front mute application and surface wave attenuation attempts. Although seismic imaging is the main technique we are planning to support this analysis with additional data from traveltime tomography, MASW and other a priori information.

  9. An experimental and numerical study of wind turbine seismic behavior

    Prowell, I.


    This dissertation presents an experimental and numerical investigation into the seismic response of modern wind turbines. Currently, no consensus exists in the industry and there is significant interest in improving prediction of the behavior of wind turbines simultaneously subjected to wind, earthquake, and operational excitation. To this end, an experimental program was planned in order to evaluate seismic loading of wind turbines. In 2004, a preliminary shake table test of a 65-kW utility ...

  10. Seismic time-lapse monitoring of potential gas hydrate dissociation around boreholes : could it be feasible? A conceptual 2D study linking geomechanical and seismic FD models

    Pecher, I.; Yang, J.; Anderson, R.; Tohidi, B.; MacBeth, C. [Heriot-Watt Univ., Edinburgh (United Kingdom). Inst. of Petroleum Engineering; Freij-Ayoub, R.; Clennell, B. [CSIRO Petroleum, Bentley, WA (Australia)


    Dissociation of gas hydrate to water and potentially overpressured gas around boreholes may pose a hazard for deep-water hydrocarbon production. Strategies to mitigate this risk include monitoring for early detection of dissociation. Seismic methods are especially promising, primarily because of a high sensitivity of P-wave velocity to gas in the pore space of unconsolidated sediments. This paper presented a study that applied commonly used rock physics modeling to predict the seismic response to gas hydrate dissociation with a focus on P-impedance and performed sensitivity tests. The geomechanical model was translated into seismic models. In order to determine which parameters needed to be particularly well calibrated in experimental and modeling studies, the sensitivity of seismic properties to a variation of input parameters was estimated. The seismic response was predicted from dissociating gas hydrates using two-dimensional finite-difference wave-propagation modeling to demonstrate that despite the small predicted lateral extent of hydrate dissociation, its pronounced effect on seismic properties should allow detection with a seismic source on a drilling platform and receivers on the seafloor. The paper described the methods, models, and results of the study. It was concluded that the key factors for predicting the seismic response of sediments to hydrate dissociation were the mode of gas hydrate distribution, gas distribution in the sediments, gas saturation, and pore pressure. 33 refs., 3 tabs., 8 figs.

  11. Developing Reading Comprehension through Metacognitive Strategies: A Review of Previous Studies

    Channa, Mansoor Ahmed; Nordin, Zaimuariffudin Shukri; Siming, Insaf Ali; Chandio, Ali Asgher; Koondher, Mansoor Ali


    This paper has reviewed the previous studies on metacognitive strategies based on planning, monitoring, and evaluating in order to develop reading comprehension. The main purpose of this review in metacognition, and reading domain is to help readers to enhance their capabilities and power reading through these strategies. The researchers reviewed…

  12. Seismic Studies of Paleo-Pockmarks on the Chatham Rise, New Zealand

    Smith, A. E.; Pecher, I. A.; Davy, B. W.; Coffin, R. B.; Rose, P. S.


    This study investigates buried pockmark features on the Chatham Rise through the analysis and interpretation of 2D seismic and Parasound data. The main objectives of this research are to establish what caused the formation of buried pockmarks on the Chatham Rise and to determine when the pockmarks were formed. The study area is located on the Western Chatham Rise, near the Canterbury Shelf off the East Coast of New Zealand. The pockmark fields were revealed through multibeam bathymetry data collected from surveys during the past 20 years. Previously, the pockmarks on the Chatham Rise were thought to have been produced by the release of methane through gas hydrate dissociation. However, recent geochemical investigations showed no indication of methane in the sediment cores. Current hypotheses for the formation of the pockmarks include groundwater fluid flow and the release of CO2 modulated by CO2 hydrates. We present the results of the spatial analysis of the pockmarks on the Western Chatham Rise and whether there are any links between the location of pockmark formation and regional geology. The structures of the pockmarks were investigated to determine how the features were formed. The spatial configuration of the pockmarks were analysed vertically for stacking and laterally for potential ties to specific horizons, particularly horizons associated with Milankovitch order climate cycles. Results show stacking and clustering of pockmarks around specific horizons and a depth window in the upper sediment in which pockmarks are formed. 2D seismic data was interpreted to build a regional geology model, through relative stratigraphy from intersecting seismic lines through the survey area. This improves the current understanding of the stratigraphy along the Chatham Rise and Canterbury Shelf areas and places the pockmark field in a regional geologic context.

  13. Study of Seismic Hazards in the Center of the State of Veracruz, MÉXICO.

    Torres Morales, G. F.; Leonardo Suárez, M.; Dávalos Sotelo, R.; Mora González, I.; Castillo Aguilar, S.


    Preliminary results obtained from the project "Microzonation of geological and hydrometeorological hazards for conurbations of Orizaba, Veracruz, and major sites located in the lower sub-basins: The Antigua and Jamapa" are presented. These project was supported by the Joint Funds CONACyT-Veracruz state government. It was developed a probabilistic seismic hazard assessment (henceforth PSHA) in the central area of Veracruz State, mainly in a region bounded by the watersheds of the rivers Jamapa and Antigua, whit the aim to evaluate the geological and hydrometeorological hazards in this region. The project pays most attention to extreme weather phenomena, floods and earthquakes, in order to calculate the risk induced by previous for landslides and rock falls. In addition, as part of the study, the PSHA was developed considered the site effect in the urban zones of the cities Xalapa and Orizaba; the site effects were incorporated by a standard format proposed in studies of microzonation and its application in computer systems, which allows to optimize and condense microzonation studies in a city. The results obtained from the PSHA are presented through to seismic hazard maps (hazard footprints), exceedance rate curves and uniform hazard spectrum for different spectral ordinates, between 0.01 and 5.0 seconds, associated to selected return periods: 72, 225, 475 and 2475 years.

  14. Efficient big data assimilation through sparse representation: A 3D benchmark case study in seismic history matching

    Luo, Xiaodong; Jakobsen, Morten; Nævdal, Geir


    In a previous work \\citep{luo2016sparse2d_spej}, the authors proposed an ensemble-based 4D seismic history matching (SHM) framework, which has some relatively new ingredients, in terms of the type of seismic data in choice, the way to handle big seismic data and related data noise estimation, and the use of a recently developed iterative ensemble history matching algorithm. In seismic history matching, it is customary to use inverted seismic attributes, such as acoustic impedance, as the observed data. In doing so, extra uncertainties may arise during the inversion processes. The proposed SHM framework avoids such intermediate inversion processes by adopting amplitude versus angle (AVA) data. In addition, SHM typically involves assimilating a large amount of observed seismic attributes into reservoir models. To handle the big-data problem in SHM, the proposed framework adopts the following wavelet-based sparse representation procedure: First, a discrete wavelet transform is applied to observed seismic attribu...

  15. Sourcing quality-of-life weights obtained from previous studies: theory and reality in Korea.

    Bae, SeungJin; Bae, Eun Young; Lim, Sang Hee


    The quality-of-life weights obtained in previous studies are frequently used in cost-utility analyses. The purpose of this study is to describe how the values obtained in previous studies are incorporated into the industry submissions requesting listing at the Korean National Health Insurance (NHI), focusing on the issues discussed in theoretical studies and national guidelines. The industry submissions requesting listing at the Korean NHI from January 2007 until December 2009 were evaluated by two independent researchers at the Health Insurance Review and Assessment Service (HIRA). Specifically, we observed the methods that were used to pool, predict joint health state utilities, and retain consistency within submissions in terms of the issues discussed in methodological research papers and recommendations from national guidelines. More than half of the submissions used QALY as an outcome measure, and most of these submissions were sourced from prior studies. Heterogeneous methodologies were frequently used within a submission, with the inconsistent use of upper and lower anchors being prevalent. Assumptions behind measuring joint health state utilities or pooling multiple values for single health states were omitted in all submissions. Most national guidelines were rather vague regarding how to predict joint health states, how to select the best available value, how to maintain consistency within a submission, and how to generalize values obtained from prior studies. Previously-generated values were commonly sourced, but this practice was frequently related to inconsistencies within and among submissions. Attention should be paid to the consistency and transparency of the value, especially if the value is sourced from prior studies.

  16. Seismic response and stability of underground rock caverns: a case study of Baihetan underground cavern complex

    Cui, Zhen; Sheng, Qian; Leng, Xianlun; Chen, Jian


    The seismic stability of the underground cavern complex, which houses the Baihetan hydropower plant in Yunnan Province, China, currently the world's 2nd largest underground rock cavern group, is studied in this article...

  17. Uranium Groundwater Monitoring and Seismic Analysis: A Case Study of the Gran Sasso Hydrogeological Basin, Italy

    Ciarletti, Marta; Plastino, Wolfango; Peresan, Antonella; Nisi, Stefano; Copia, Lorenzo; Panza, Giuliano F.; Povinec, Pavel P.


    Uranium groundwater anomalies, observed before the L'Aquila earthquake (April 6th, 2009) and before the seismic swarm, which occurred in the second half of 2010, represent a key geochemical signal of a progressive increase of deep fluids fluxes at middle-lower crustal levels associated with the geodynamics of the earthquake. In this paper, temporal variations of uranium groundwater are studied in association with the seismic pattern around Gran Sasso National Laboratory (LNGS-INFN). The normalized seismic energy release and the number of earthquakes are analyzed in detail by means of monthly sliding time windows. They are compared with uranium anomalies to highlight any possible correlation.

  18. Seismic slope stability of embankments: a comparative study on EC8 provisions

    Zania, Varvara; Tsompanakis, Y.; Psarropoulos, P.N.


    According to EC8 provisions, seismic stability assessment of natural slopes is currently performed based on simplified methods i.e. the pseudostatic and the Newmark’s sliding block method. The application of these methods requires the beforehand consideration of major assumptions necessary...... for the selection of either the seismic coefficient or the acceleration time history of the rigid block. Although both ULS and SLS are defined according to acceptable level of deformations at the slope, the assigned level of displacements is not clarified. In the current study the seismic slope stability...

  19. Seismic monitoring of soft-rock landslides: New case study at Pechgraben mudslide - Upper Austria

    Vouillamoz, Naomi; Santoyo, Juan Carlos; Ottowitz, David; Jochum, Birgit; Pfeiler, Stefan; Supper, Robert; Joswig, Manfred


    Creeping soft-rock landslides trigger various seismic signals which relate to key dynamics of the slope instability. A new seismic monitoring study is carried out at Pechgraben - Upper Austria, where a clay-shale rich mudslide was reactivated in summer 2013 after heavy rainfalls. The well geophysical instrumentation of the Pechgraben mudslide by the Geological Survey of Austria (LAMOND network including permanent ERT, GPS, piezometers, soil temperature/humidity and photomonitoring) is expected as a better basis for joint interpretation of seismic source processes. Seismic data are acquired by small-aperture (< 30 m) sparse seismic arrays. Potential events are recognized by frequency-time signatures in sonograms, where sonograms are spectrograms featuring a frequency-dependant noise adaptation that enhance the display of weak signal energy down to the noise threshold. Further signal evaluation follows an interactive scheme where semi-automated beam forming method enables for approximate source location. Three seismic arrays where deployed at Pechgraben in October 2015 for an eight days feasibility study. About 200 seismic signals potentially triggered by the landslide were manually picked on night-time measurements. Target signals occur in tremor-like sequences and have duration within 1 - 8 seconds. Local magnitudes are calibrated down to ML -1.5 (Wood-Anderson amplitude ≈ 0.1 μm in 100 m distance). Observed waveforms display high degree of similarity with seismic signals catalogued at other soft-rock landslides suggesting that a general typology of seismic source processes could be established for creeping soft-rock instabilities with potential further implications in landslide mitigation and forecasting.

  20. Exploring the effects of seismicity on landslides and catchment sediment yield: An Italian case study

    Vanmaercke, Matthias; Ardizzone, Francesca; Rossi, Mauro; Guzzetti, Fausto


    Recent studies showed that contemporary average catchment sediment yields (SY, [t km- 2 y- 1]) at regional and continental scales are often strongly correlated to spatial patterns of seismic activity. Nonetheless, we currently have little insights into the mechanisms that explain these correlations. We investigated how spatial patterns of SY in Italy are linked to patterns of seismic activity. For a dataset of 103 Italian catchments with average SY measured over a period of years to decades, we extracted tectonic and none-tectonic variables that potentially explain observed differences in SY. These include proxies for vertical uplift rates and cumulative seismic moments (CSM) associated with historic earthquakes of different ranges of magnitude. Results showed that also across Italy, SY is significantly correlated to seismicity. However, SY showed much stronger correlations with proxies of seismicity relating to small but frequent earthquakes (2 ≤ Mw landslide-triggering earthquakes (Mw ≥ 4). Analyses of a dataset of about 500,000 landslides across Italy showed very comparable trends: spatial patterns of landslides within similar lithological units generally show a significant positive correlation with CSM of weak but frequent seismicity and generally not with CSM of large earthquakes. These results suggest that, on a decadal time scale and at a regional/continental spatial scale, frequent but relatively weak seismicity may exert a more important geomorphic impact than large earthquake events or tectonic uplift.

  1. Seismicity studies in the region of the Cerro Prieto Geothermal Field

    Albores, A.; Reyes, A.; Brune, J.N.; Gonzalez, J.; Garcilazo, L.; Suarez, F.


    This paper reports results from seismicity studies in the region of the Cerro Prieto geothermal field. These studies were conducted with local short period seismic arrays during 1974-1975 and 1977-1978. During the latter period, horizontal seismometers were used for better control on the S-wave arrival times. Locations were obtained for about 200 events and composite fault plane solutions were obtained for five groups of events. 16 refs.

  2. Vibrations of twisted cantilevered plates - Summary of previous and current studies

    Leissa, A. W.; Macbain, J. C.; Kielb, R. E.


    This work summarizes a comprehensive study made of the free vibrations of twisted, cantilevered plates of rectangular planform. Numerous theoretical and experimental investigations previously made by others have resulted in frequency results which disagree considerably. To clarify the problem a joint industry/government/university research effort was initiated to obtain comprehensive theoretical and experimental results for models having useful ranges of aspect ratios, thickness ratios and twist angles. Theoretical data came from 19 independent computer analyses, including finite element, shell theory and beam theory idealizations. Two independent sets of experimental data were also obtained. The theoretical and experimental results are summarized and compared.

  3. Statistical Studies of Induced and Triggered Seismicity at The Geysers, California

    Hawkins, A.; Turcotte, D. L.; Yıkılmaz, M. B.; Kellogg, L. H.; Rundle, J. B.


    This study considers the statistics of fluid-induced and remotely triggered seismicity at The Geysers geothermal field, California. Little seismicity was reported before steam extraction began in 1960. Beginning in 1980 the residual water associated with power generation was re-injected, producing induced seismicity. Beginning in 1997 large-scale injections of cold water began to enhance the generation of steam. This led to an increase in M 1.25 events. The GR and decay statistics are given. However, to separate aftershocks from remotely triggered earthquakes, an additional triggered sequence is studied. The M = 7.2 4/4/10 Baja earthquake triggered some 34 M > 1.25 earthquakes at The Geysers in the first hour including an M = 3.37 event. We conclude that the remotely triggered seismicity is dominated by local aftershocks of the larger remotely triggered earthquakes.

  4. Causality between expansion of seismic cloud and maximum magnitude of induced seismicity in geothermal field

    Mukuhira, Yusuke; Asanuma, Hiroshi; Ito, Takatoshi; Häring, Markus


    is seismic moment density (Mo/m3) and V stim is stimulated rock volume (m3). Mopossible = D ∗ V stim(1) We applied this conceptual model to real microseismic data set from Basel EGS project where several induced seismicity with large magnitude occurred and brought constructive damage. Using the hypocenter location determined by the researcher of Tohoku Univ., Japan and moment magnitude estimated from Geothermal Explorers Ltd., operating company, we were able to estimate reasonable seismic moment density meaning that one representative parameter exists and can characterize seismic activity at Basel at each time step. With stimulated rock volume which was also inferred from microseismic information, we estimated possible seismic moment and assess the difference with observed value. Possible seismic moment significantly increased after shut-in when the seismic cloud (stimulated zone) mostly progressed, resulting that the difference with the observed cumulative seismic moment automatically became larger. This suggests that there is moderate seismic moment which will be released in near future. In next few hours, the largest event actually occurred. Therefore, our proposed model was successfully able to forecast occurrence of the large events. Furthermore, best forecast of maximum magnitude was Mw 3 level and the largest event was Mw 3.41, showing reasonable performance in terms of quantitative forecast in magnitude. Our attempt to assess the seismic activity from microseismic information was successful and it also suggested magnitude release can be correlate with the expansion of seismic cloud as the definition of possible seismic moment model indicates. This relationship has been observed in microseismic observational study and several previous study also suggested their correlation with stress released rock volume. Our model showed harmonic results with these studies and provide practical method having clear physical meaning to assess the seismic activity in real

  5. Assessing the seismic coupling of shallow continental faults and its impact on seismic hazard estimates: a case-study from Italy

    Carafa, Michele M. C.; Valensise, Gianluca; Bird, Peter


    SUMMARYWe propose an objective and reproducible algorithmic path to forecast seismicity in Italy from long-term deformation models. These models are appropriate for Italy and its neighboring countries and seas thanks to the availability of rich, reliable and regularly updated historical earthquake and seismogenic fault databases, and to the density of permanent GPS stations. However, so far little has been done to assess the seismic coupling of Italian active faults, i.e. to quantify their ability to release earthquakes. This must be determined in order to use geodetic and active faulting observations in alternative seismicity models, to overcome possible limitations of the earthquake record for the assessment of seismic hazard. We use a probabilistic method to assign upper crustal earthquakes from the historical catalogue to their presumed causative faults, then collect all the events into three subcatalogues corresponding to the compressional, extensional and strike-slip faulting classes. We then determine the parameters of their Gutenberg-Richter frequency/magnitude relations using maximum-likelihood methods and integrate these distributions to estimate the long-term seismic moment rate for each class. Finally, we compare these seismicity rates to the long-term tectonic deformation based on GPS data, thus determining the coupled thickness (and estimating seismic coupling) for each fault class. We find that in our study region the seismic coupling and the related coupled thickness is on average two times larger for extensional than for compressional faults. As for the spatial distribution of earthquake rates, a larger number of events is predicted for the extensional settings of the Apennines chain, in agreement with the inferred seismic coupling but also with the long-term strain rates. We also find that the frequency/magnitude distributions indicate that the largest earthquakes occur in extensional settings, whereas compressional faults are expected to host

  6. Proposed seismic hazard maps of Sumatra and Java Islands and microzonation study of Jakarta City, Indonesia

    Masyhur Irsyam; Donny T Dangkua; Hendriyawan; Drajat Hoedajanto; Bigman M Hutapea; Engkon K Kertapati; Teddy Boen; Mark D Petersen


    This paper presents the development of spectral hazard maps for Sumatra and Java islands, Indonesia and microzonation study for Jakarta city. The purpose of this study is to propose a revision of the seismic hazard map in Indonesian Seismic Code SNI 03-1726-2002. Some improvements in seismic hazard analysis were implemented in the analysis by considering the recent seismic activities around Java and Sumatra. The seismic hazard analysis was carried out using 3-dimension (3-D) seismic source models (fault source model) using the latest research works regarding the tectonic setting of Sumatra and Java. Two hazard levels were analysed for representing 10% and 2% probability of exceedance (PE) in 50 years ground motions for Sumatra and Java. Peak ground acceleration contour maps for those two hazard levels and two additional macrozonation maps for 10% PE in 50 years were produced during this research. These two additional maps represent short period (0.2 s) and long-period (1.0 s) spectra values at the bedrock. Microzonation study is performed in order to obtain ground motion parameters such as acceleration, amplification factor and response spectra at the surface of Jakarta. The analyses were carried out using nonlinear approach. The results were used to develop contour of acceleration at the surface of Jakarta. Finally, the design response spectra for structural design purposes are proposed in this study.

  7. Experimental study on the impact-induced seismic wave propagating through granular materials: Implications for a future asteroid mission

    Yasui, M.; Matsumoto, E.; Arakawa, M.; Matsue, K.; Kobayashi, N.


    with a diameter of 10 mm and a height of 10 mm, and stainless steel and alumina balls with a diameter of 3 mm. The stainless steel and alumina projectiles were accelerated with a sabot made of polyethylene. The impact velocity was from 20 to 100 m/s. The target was a non-cohesive glass bead with a mean particle diameter of 200 μ m prepared by putting the particles into a container with a diameter of 300 mm and a height of 100 mm, up to 80 mm depth. The target porosity was about 40%. A chamber that we set the target in was evacuated below 1000 Pa. Three accelerometers (response frequency projectile types. These results mean that the seismic wave attenuates with a similar waveform scaled by the crater radius on the same target. The duration keeping the maximum acceleration was measured to have a half width of g_max peak on the waveform, and it was estimated to be ˜0.3 ms. This value is almost consistent with the penetration time of projectiles estimated by the model proposed by Niimi et al. (2011). McGarr et al. (1969) studied the momentum conversion efficiency from the projectile momentum to the target momentum transferred by the seismic wave and obtained it as the ratio of the momentum calculated by the particle motion, I, to the projectile momentum, I_p. In our study, the I/I_p was obtained to be 0.23-1.56. This range was almost consistent with that of McGarr et al. (1969), 0.39-1.62. We can conclude that I/I_p is independent of the impact velocity. Implications for planetary exploration: According to the previous results, we can discuss the sensitivity of the seismometer to detect the seismic wave induced by an artificial impactor on asteroids. We calculated the maximum acceleration on asteroids with two different sizes, such as the sizes of Eros and 1999JU3, by assuming that the projectile made of copper with a mass of 2 kg impacted at 2 km/s. In this calculation, we used the crater scaling law and the attenuation equation of g_max obtained in our study. As a

  8. A Study of Thin Sandstone Reservoirs by High-resolution Seismic Inversion

    Ning Songhua


    In this paper seismic inversion was used as a key technique and the seismic wavelet most suitable to the actual underground situation was extracted with the higher-order statistics algorithm. The wavelets extracted in this way and the wavelets extracted with the seismic statistics techniques were used separately for inverting the seismic data of the southern part of Tahe oilfield, Tarim basin. The results showed that the resolution of the wavelet inversion with the higher-order statistics method was greatly improved, and the wavelet-inverted section could better distinguish the thin sandstone reservoirs of the upper and lower Carboniferous and their lateral distribution, providing a reliable basis of analysis for the study of thin sandstone reservoirs.

  9. Realistic modelling of the seismic input Site effects and parametric studies

    Romanelli, F; Vaccari, F


    We illustrate the work done in the framework of a large international cooperation, showing the very recent numerical experiments carried out within the framework of the EC project 'Advanced methods for assessing the seismic vulnerability of existing motorway bridges' (VAB) to assess the importance of non-synchronous seismic excitation of long structures. The definition of the seismic input at the Warth bridge site, i.e. the determination of the seismic ground motion due to an earthquake with a given magnitude and epicentral distance from the site, has been done following a theoretical approach. In order to perform an accurate and realistic estimate of site effects and of differential motion it is necessary to make a parametric study that takes into account the complex combination of the source and propagation parameters, in realistic geological structures. The computation of a wide set of time histories and spectral information, corresponding to possible seismotectonic scenarios for different sources and stru...


    Gurpreet Kaur


    Full Text Available Previous caesarean section sparks an area of controversy in Obstetrics. The management of women with previous caesarean section regarding the mode of delivery whether to opt for repeat caesarean section or vaginal delivery, is an area of debate. Very often the decision on management is not made on Principle of sound reasoning and many who choose the elective repeat caesarean section do so to circumvent the anxious moment that arise during conduct ion of labour. AIMS AND OBJECTIVE: To determine the maternal and fetal outcome in relation to type of delivery . MATERIALS AND METHOD S: A 18 month prospective observational study was conducted where in 150 patients who had a term pregnancy with a history of prior LSCS were included after obtaining their consent for participation. The obstetric and fetal outcomes of these patients in the present pregnancy were analyzed by Z test. RESULTS: Out of the 150 subjects 78 ( 52% were in age group of 26 - 30 years, 106 ( 70.67% patients belonged to the urban population, 116 ( 77.33% were booked patie nts, 107 ( 71.33% were housewives, 122 ( 81.33% belonged to middle class and 22 ( 14.67% were from high socio economic status. 67 ( 44.67% were second gravid, 112 ( 74.67% were para 1. Out of total 134 patients 29 ( 21.64% had elective caesarean section and 5 ( 3 .73% patients came as emergency admission and underwent caesarean section. Out of 134 patients, with one previous caesarean section. 32 had spontaneous onset of labour. Out of which 20 ( 68.97% had vaginal delivery and 9 ( 31.03% had repeat caesarean section. 13 patients had augmentation, 11 ( 84.62% had vaginal delivery and 2 ( 15.38% had caesarean section. In 58 patients labour was induced 29 ( 50% had section. 14 patients out of 50 who had previous 2 caesarean section only 1 ( 7.69% patient had spontane ous onset of labour and had caesarean section. 3 ( 92.86% patients had elective caesarean section. There were only 2 patients with previous 3 caesarean

  11. A Preliminary Study of Seismicity at Ceboruco, Volcano, Nayarit, Mexico

    Sanchez, J. J.; Nunez-Cornu, F. J.; Suarez-Plascencia, C.; Trejo-Gomez, E.


    Ceboruco Volcano is located northwestern of Tepic-Zacoalco graben (Jalisco, Mexico). Its volcanic activity can be divided in four eruptive cycles differentiated by their volcano explosivity index (VEI) and chemical variations as well. As a result of andesitic effusive activity, during the first cycle the "paleo-Ceboruco" edifice was constructed. The end of this cycle is defined by a plinian eruption (VEI is estimated between 3 and 4) which occurred some 1020 years ago and formed the external caldera. During the second cycle an andesitic dome extruded in the interior of the caldera. The dome, called Dos Equis, collapsed and formed the internal caldera. The third cycle is represented by andesitic lava flows which partially cover the northern and south-southwestern part of the edifice. The last cycle is represented by historic andesitic lava flows located in the southwestern flank of the volcano. In February 2003 as part of an agreement with Nayarit Civil Defense a seismic station was installed in the SW flank of the volcano. The station is equipped with a Marslite (lennartz) digitizer with a 3DLe 1Hz. seismic sensor. Detection system is based on a STA/LTA recording algorithm. More than 2000 small earthquakes have been attributed to various local sources, and some of this earthquakes are possibly located beneath Ceboruco volcano. A preliminary classification separates high frequency and low frequency seismic events. The sources of high frequency earthquakes appear to be distributed as evidenced from waveforms variety and changing S-P arrivals separations. The low frequency seismic events also show varying signatures and some of them exhibit extended coda, including some monochromatic character.

  12. Case-control study for colorectal cancer genetic susceptibility in EPICOLON: previously identified variants and mucins

    Moreno Victor


    Full Text Available Abstract Background Colorectal cancer (CRC is the second leading cause of cancer death in developed countries. Familial aggregation in CRC is also important outside syndromic forms and, in this case, a polygenic model with several common low-penetrance alleles contributing to CRC genetic predisposition could be hypothesized. Mucins and GALNTs (N-acetylgalactosaminyltransferase are interesting candidates for CRC genetic susceptibility and have not been previously evaluated. We present results for ten genetic variants linked to CRC risk in previous studies (previously identified category and 18 selected variants from the mucin gene family in a case-control association study from the Spanish EPICOLON consortium. Methods CRC cases and matched controls were from EPICOLON, a prospective, multicenter, nationwide Spanish initiative, comprised of two independent stages. Stage 1 corresponded to 515 CRC cases and 515 controls, whereas stage 2 consisted of 901 CRC cases and 909 controls. Also, an independent cohort of 549 CRC cases and 599 controls outside EPICOLON was available for additional replication. Genotyping was performed for ten previously identified SNPs in ADH1C, APC, CCDN1, IL6, IL8, IRS1, MTHFR, PPARG, VDR and ARL11, and 18 selected variants in the mucin gene family. Results None of the 28 SNPs analyzed in our study was found to be associated with CRC risk. Although four SNPs were significant with a P-value ADH1C (OR = 1.63, 95% CI = 1.06-2.50, P-value = 0.02, recessive, rs1800795 in IL6 (OR = 1.62, 95% CI = 1.10-2.37, P-value = 0.01, recessive, rs3803185 in ARL11 (OR = 1.58, 95% CI = 1.17-2.15, P-value = 0.007, codominant, and rs2102302 in GALNTL2 (OR = 1.20, 95% CI = 1.00-1.44, P-value = 0.04, log-additive 0, 1, 2 alleles], only rs3803185 achieved statistical significance in EPICOLON stage 2 (OR = 1.34, 95% CI = 1.06-1.69, P-value = 0.01, recessive. In the joint analysis for both stages, results were only significant for rs3803185 (OR = 1

  13. A longitudinal study of plasma insulin and glucagon in women with previous gestational diabetes

    Damm, P; Kühl, C; Hornnes, P


    OBJECTIVE: To investigate whether plasma insulin or glucagon predicts later development of diabetes in women with gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: The subjects studied were 91 women with diet-treated GDM and 33 healthy women. Plasma insulin and glucagon during a 50......-g oral glucose tolerance test (OGTT) were measured during pregnancy, postpartum, and at follow-up 5-11 years later. At follow-up, the women were also examined with a 75-g OGTT or an intravenous glucagon test. RESULTS: Twenty-seven (30%) of the women with previous GDM had abnormal glucose tolerance...... response) at all time points investigated; this was also found when only nonobese glucose-tolerant women were examined. Low insulin secretion during pregnancy together with a high fasting plasma glucose level at the diagnostic OGTT in pregnancy and hyperglycemia during the postpartum OGTT were predictive...

  14. Seismic ambient noise study at Bouillante geothermal system, French Antilles

    Jousset, Philippe; Bitri, Adnan; Loiseau, Justine; Bouchot, Vincent


    Seismic ambient noise analyses have been shown to be able to image structural features of the crust and to monitor underground changes of seismic wave ground velocity. We present results of cross-correlation techniques at Bouillante geothermal field, French Antilles, the largest French high-enthalpy geothermal system exploited for electrical power from 3 collocated productive wells. Two power plants generate electricity and fluid extraction rate varies with time and wells are sometimes closed for equipment maintenance. Under the support of the French Environment and Energy Management Agency (ADEME) and the French Research Agency (ANR), BRGM has been analyzing seismic data from a network comprising 5 broadband seismological stations set-up at Bouillante area since 2004. Amongst the large number of earthquakes recorded, we show that no single earthquake could be related to the fluid exploitation. Instead, they are due to the intense regional seismicity. Despite the small number of stations, surface wave travel times computed from ambient noise cross-correlation for about a year suggest that the velocity structure is consistent with the conceptual model of hot (250°C) and permeable (fractured) geothermal reservoir of Bouillante. We show at several instances that changes of the fluid extraction rate have spatial and temporal slight perturbations on medium wave velocity. For example, when the production stops for maintenance, velocity increases by several percent and with larger amplitude at stations within 1 km distance from the production wells and lower amplitudes (by more than 50 %) at stations further than 2 km from the production wells. In addition, we note that velocity perturbations have a delay of at most 1 day at further stations. We discuss several mechanisms to explain those observations like pressure and stress variations in the geothermal system. The results suggest that the inferred velocity changes, owing the fine sensibility of the inter

  15. Study on Seismic Behavior of Recycled Concrete Energy-efficient Homes Structure Wall

    Dong Lan


    Full Text Available The main point is to study the seismic behavior of the lattice type recycled concrete energy saving wall under low-cyclic loading,to provide the basis for the seismic performance of application of recycled concrete lattice wall in energy-saving residential structure. Design two walls with the same structure measures, include Lattice type recycled concrete wall and natural concrete wall, they are tested under low-cycle repetitive loading, compared failure mode and seismic performance in different reinforcement conditions of side column. The bearing capacity and ductility of recycled aggregate concrete are better than natural aggregate concrete, The stiffness degradation curves and the skeleton curves of the walls are basically the same, both of them have better seismic energy dissipation capacity. Lattice type concrete wall is good at seismic performance, recycled aggregate concrete is good at plastic deformation ability, it is advantageous to seismic energy dissipation of wall, it can be applied in energy efficient residential structure wall.

  16. Experimental study on seismic behaviors of steel-concrete composite frames

    戚菁菁; 蒋丽忠


    Steel-concrete composite frames are seeing increased use in earthquake region because of their excellent structural characteristics, including high strength, stiffness, and good ductility. However, there exist gaps in the knowledge of seismic behavior and the design provisions for these structures. In order to better understand the seismic behaviors of composite frame systems, eight steel-concrete composite frames were designed. These composite frames were composed of steel-concrete composite beams and concrete filled steel tube columns. The axial compression ratio of column, slenderness ratio and linear stiffness ratio of beam to column were selected as main design parameters. The low reversed cyclic loading tests of composite frame system were carried out. Based on test results, the seismic behaviors of composite frames such as failure mode, hysteresis curve, strength degradation, rigidity degradation, ductility and energy dissipation were studied. Known from the test phenomenon, the main cause of damage is the out-of-plane deformation of steel beam and the yielding destruction of column heel. The hysteretic loops of composite frame appear a spindle shape and no obvious pinch phenomenon. The results demonstrate that this type of composite frame has favorable seismic behaviors. Furthermore, the effects of design parameters on seismic behaviors were also discussed. The results of the experiment show that the different design parameter has different influence rule on seismic behaviors of composite frame.

  17. Experimental study on seismic behaviors of steel-concrete composite frames

    戚菁菁; 蒋丽忠


    Steel−concrete composite frames are seeing increased use in earthquake region because of their excellent structural characteristics, including high strength, stiffness, and good ductility. However, there exist gaps in the knowledge of seismic behavior and the design provisions for these structures. In order to better understand the seismic behaviors of composite frame systems, eight steel−concrete composite frames were designed. These composite frames were composed of steel−concrete composite beams and concrete filled steel tube columns. The axial compression ratio of column, slenderness ratio and linear stiffness ratio of beam to column were selected as main design parameters. The low reversed cyclic loading tests of composite frame system were carried out. Based on test results, the seismic behaviors of composite frames such as failure mode, hysteresis curve, strength degradation, rigidity degradation, ductility and energy dissipation were studied. Known from the test phenomenon, the main cause of damage is the out-of-plane deformation of steel beam and the yielding destruction of column heel. The hysteretic loops of composite frame appear a spindle shape and no obvious pinch phenomenon. The results demonstrate that this type of composite frame has favorable seismic behaviors. Furthermore, the effects of design parameters on seismic behaviors were also discussed. The results of the experiment show that the different design parameter has different influence rule on seismic behaviors of composite frame.

  18. A study about the interest and previous contact of high school students with Astronomy

    Carvalho, C. L.; Zanitti, M. H. R.; Felicidade, B. L.; Gomes, A. D. T.; Dias, E. W.; Coelho, F. O.


    The currently problems in Astronomy teaching in Brazilian Basic Education contrast with the space, and the popularity that astronomical themes have in various media in the country. In this work, we present the results of a study about the interest, and previous contact of high school students from a public school in the city of "São João del-Rei"/MG with topics related to Astronomy. The study and the pedagogical intervention were carried out by students of the PIBID/CAPES/UFSJ. The intervention was performed through an oral exposition with the students' participation, followed by the use of the Stellarium program. The results suggest the majority of students surveyed are interested in Astronomy, and have had some contact with the area. However, some inconsistencies in their responses were identified and examined. The implications for research and for Astronomy Education are discussed. We also make some considerations about relationship between the lack of specific knowledge and the misinformation as one possible reason for the little interest of students in various areas of Science.

  19. Regional seismic study of the southern Apennine oil discoveries

    Finetti, I.R. [Universita di Trieste (Italy); Del Ben, A. [GEXON International, Trieste (Italy)


    Based on interpretation of conspicuous regional detailed seismic data sets collected in several years of scientific and professional geophysical exploration activity, the Authors outline basinal conditions of the source rocks deposition during Mesozoic and successive Cenozoic thrusting deformation of the oil basin of Southern Apennine, Italy. Mainly due to its tectonic complexity, only in the last years in the Southern Apennine have been discovered promising oil fields (i.e. Mt. Alpi, Tempa Rossa and Costa Molina). This thrust belt area is now actively explored with a relevant effort to understand the involved detailed tectonic setting and connected geodynamic process. Also basin evolution and source rock distribution are key aspects for success in the exploration activity. The deformation processes of the Apennine Chain are so severe and complex that it is objectively difficult to understand the occurred evolution only investigating local areas, even if in advanced manner. Indeed, for a correct understanding it is indispensable to regionally extend the tectonic inversion firstly to those areas which were involved in Mesozoic by those extensional processes that control the source rocks deposition of the discovered oil fields. This investigation may also clear out the potential areal extent of the discovered producing zone. Successively, it is necessary to reconstruct the young compressive complex tectonization of the involved thrust belt. The regional seismic exploration shows very clearly that large part of the Ionian Sea represents the southeastward not tectonized continuation of the source rocks area of the oil discoveries, locally known with the name of {open_quotes}Lagonegrese{close_quotes}. Seismic information indicates also that the source rocks deposition is associated with a rift activity occurred in Triassic and pursued with a second phase in Middle Jurassic with the formation of a large graben separating the Apulian Platform from the African Plate.

  20. Religious Identity in Iranian Society: A Systematic Review of Previous Studies (2001-2013


    literature on identity, evidence suggests that the role of religion in shaping individuals' and group's identity is widely ignored. However, a growing number of studies have begun to take into consideration the key role of religion (Arweck & Nesbitt 2010, King and Boyatzis 2004, Peek 2005. This article has attempted to review systematically previous research and conceptualizations on the religious identity based on national studies and surveys and academic dissertations.     Materials and Methods   As mentioned, the purpose of this study was to review the results of some influential researches in the field of religious identity. To get this purpose, one of the best known methods for reviewing previous studies, a systematic review, was applied. Systematic review deals with establishing and synthesizing of researches and evidences with focus on a specific question. This occurs through the organized, transparent, formal, clear and flexible procedures and processes. A systematic review of research is not limited to review the history and this overview and review can be used in different levels, fields and goals. During the first phase of the study, terms of "religious identity", "Islamic identity", "Iranian identity" and "religious identity" was searched at libraries and research centers and in databases such as Center for Scientific Information Database (SID, a database of Iranian journals and magazines (Magiran, Noor specialized journals database, and Science and Information Technology Institute (IrnaDoc. After reviewing the gathered documents and specifying its relationship with the object and purpose of the study, a total of 47 documents were selected. Documents based on the five major parameter were summarized and reviewed: 1-general information, 2-goals and research questions, 3-research methodology, 4-variables, 5-findings     Discussion of Results and Conclusion   Findings show that in the highest percentage (38.2% of researches, religious identity has been

  1. Distinguishing induced seismicity from natural seismicity in Ohio: Demonstrating the utility of waveform template matching

    Skoumal, Robert J.; Brudzinski, Michael R.; Currie, Brian S.


    This study investigated the utility of multistation waveform cross correlation to help discern induced seismicity. Template matching was applied to all Ohio earthquakes cataloged since the arrival of nearby EarthScope TA stations in late 2010. Earthquakes that were within 5 km of fluid injection activities in regions that lacked previously documented seismicity were found to be swarmy. Moreover, the larger number of events produced by template matching for these swarmy sequences made it easier to establish more detailed temporal and spatial relationships between the seismicity and fluid injection activities, which is typically required for an earthquake to be considered induced. Study results detected three previously documented induced sequences (Youngstown, Poland Township, and Harrison County) and provided evidence that suggests two additional cases of induced seismicity (Belmont/Guernsey County and Washington County). Evidence for these cases suggested that unusual swarm-like behaviors in regions that lack previously documented seismicity can be used to help distinguish induced seismicity, complementing the traditional identification of an anthropogenic source spatially and temporally correlated with the seismicity. In support of this finding, we identified 17 additional cataloged earthquakes in regions of previously documented seismicity and away from disposal wells or hydraulic fracturing that returned very few template matches. The lack of swarminess helps to indicate that these events are most likely naturally occurring.

  2. Combining magnetic and seismic studies to constrain processes in massive stars

    Neiner, C; Coste, B; Briquet, M; Mathis, S


    The presence of pulsations influences the local parameters at the surface of massive stars and thus it modifies the Zeeman magnetic signatures. Therefore it makes the characterisation of a magnetic field in pulsating stars more difficult and the characterisation of pulsations is thus required for the study of magnetic massive stars. Conversely, the presence of a magnetic field can inhibit differential rotation and mixing in massive stars and thus provides important constraints for seismic modelling based on pulsation studies. As a consequence, it is necessary to combine spectropolarimetric and seismic studies for all massive classical pulsators. Below we show examples of such combined studies and the interplay between physical processes.

  3. Periodic variation of stress field in the Koyna-Warna reservoir triggered seismic zone inferred from focal mechanism studies

    Rao, N. Purnachandra; Shashidhar, D.


    The Koyna-Warna region in western India is globally recognized as the premier site of reservoir triggered seismicity (RTS) associated with the Koyna and Warna reservoirs. The region is characterized by continuous seismic activity observed since several decades, including the world's largest triggered earthquake of M6.3 which occurred in Koyna in 1967. While the role of reservoirs in triggering earthquakes has been widely discussed, the actual tectonic mechanism controlling earthquake genesis in this region is hardly understood. The Koyna-Warna region is exclusively governed by earthquakes of strike-slip and normal fault mechanism distinct from the thrust faulting seen in other active zones in the Indian region. In the present study, a comprehensive catalog of 50 focal mechanism solutions of earthquakes that occurred during the last 45 years in the Koyna-Warna region is developed, both from previous literature and from moment tensor inversion studies by the authors using broadband data from a local seismic network operating since 2005. The seismicity and fault plane data have enabled precise delineation of trends of the major causative faults, which are further accentuated using the double-difference technique. Stress inversion of the focal mechanism data has provided the best fitting principal compressive and tensile stress field of the region, which in conjunction with the deciphered fault zones provides a feasible model of seismogenesis in this region. Based on the observed temporal variation of faulting mechanism a model of alternating cycles of predominantly strike-slip and normal faulting is proposed, which is attributed to a periodic peaking and relaxation respectively of the horizontal compressive stress field in this region due to the Indian plate collision with Eurasia.

  4. Phase II study of pegylated liposomal doxorubicin plus vinorelbine in breast cancer with previous anthracycline exposure.

    Martin, Miguel; García-Donas, Jesus; Casado, Antonio; de la Gándara, Isabel; Pérez-Segura, Pedro; García-Saenz, Jose-Angel; Ibáñez, Gabriel; Loboff, Belen; García-Ledo, Gemma; Moreno, Fernando; Grande, Enrique; Diaz-Rubio, Eduardo


    Thirty-five patients with metastatic breast cancer (MBC) entered a phase II study of pegylated liposomal doxorubicin 35 mg/m2 intravenously (i.v.) on day 1 plus vinorelbine 30 mg/m2 i.v. on day 1 every 4 weeks. Patients were required to have measurable disease, previous chemotherapy with an anthracycline-containing regimen, and a normal left ventricular ejection fraction (LVEF). Thirty-four patients were assessable for response and toxicity. The overall response rate (on an intent-to-treat basis) was 35% (12 of 34; 95% CI, 20%-54%). One complete response and 11 partial responses were noted. In addition, 14 patients (41%) had stable disease of > 4 months duration, and 7 patients (20.5%) had disease progression. The response rates to the combination when it was used as first- and second-line chemotherapy were 31% (4 of 13) and 38% (8 of 21), respectively. Median time to disease progression was 7 months (range, 1-35 months) and median overall survival was 13 months (range, 2 to > 62 months). Neutropenia was the most frequent toxicity (grade 4 in 44% of patients and 19% of cycles), but neutropenic fever was seen in only 3 cases. No septic deaths occurred. Nonhematologic grade 3 side effects included skin toxicity (palmar-plantar erythrodysesthesia syndrome, 6%) and mucositis (15%). Late alopecia was seen in 53% of patients (grade 1 in 41%, and grade 2 in 12%). The median LVEFs were 64% (range, 50%-81%) at baseline and 62% (range, 37%-70%) after treatment. Three patients presented an LVEF decrease to < 50%; however, no clinical heart failure was noted, and 2 of these patients recovered normal values after cessation of therapy. The combination of pegylated liposomal doxorubicin and vinorelbine can be safely administered to patients with anthracycline-pretreated MBC and is active in this population.

  5. High-resolution shear-wave seismic reflection as a tool to image near-surface subrosion structures - a case study in Bad Frankenhausen, Germany

    Wadas, Sonja H.; Polom, Ulrich; Krawczyk, Charlotte M.


    Subrosion is the subsurface leaching of soluble rocks that results in the formation of depression and collapse structures. This global phenomenon is a geohazard in urban areas. To study near-surface subrosion structures, four shear-wave seismic reflection profiles, with a total length of ca. 332 m, were carried out around the famous leaning church tower of Bad Frankenhausen in northern Thuringia, Germany, which shows an inclination of 4.93° from the vertical. Most of the geological underground of Thuringia is characterized by soluble Permian deposits, and the Kyffhäuser Southern Margin Fault is assumed to be a main pathway for water to leach the evaporite. The seismic profiles were acquired with the horizontal micro-vibrator ELVIS, developed at Leibniz Institute for Applied Geophysics (LIAG), and a 72 m long landstreamer equipped with 72 horizontal geophones. The high-resolution seismic sections show subrosion-induced structures to a depth of ca. 100 m and reveal five features associated with the leaching of Permian deposits: (1) lateral and vertical varying reflection patterns caused by strongly heterogeneous strata, (2) discontinuous reflectors, small offsets, and faults, which show the underground is heavily fractured, (3) formation of depression structures in the near-surface, (4) diffractions in the unmigrated seismic sections that indicate increased scattering of the seismic waves, and (5) varying seismic velocities and low-velocity zones that are presumably caused by fractures and upward-migrating cavities. A previously undiscovered southward-dipping listric normal fault was also found, to the north of the church. It probably serves as a pathway for water to leach the Permian formations below the church and causes the tilting of the church tower. This case study shows the potential of horizontal shear-wave seismic reflection to image near-surface subrosion structures in an urban environment with a horizontal resolution of less than 1 m in the uppermost 10

  6. Studying CO2 storage with ambient-noise seismic interferometry: A combined numerical feasibility study and field-data example for Ketzin, Germany

    Boullenger, B.; Verdel, A.; Paap, B.; Thorbecke, J.W.; Draganov, D.S.


    Seismic interferometry applied to ambient-noise measurements allows the retrieval of the seismic response between pairs of receivers. We studied ambient-noise seismic interferometry (ANSI) to retrieve time-lapse reflection responses from a reservoir during CO2 geologic sequestration, using the case

  7. Subtle traps prediction using sequence stratigraphy and 3D seismic technology: A case study from Qikou depression in Huanghua basin

    MAO Ning-bo; DAI Ta-gen; PENG Sheng-lin


    Forecasting subtle traps by sequence stratigraphy and 3D seismic data is a sensitive topic in hydrocarbon exploration. Research on subtle traps by geophysical data is the most popular and difficult. Based on the sufficiently drilling data, log data, core data and 3D seismic data, sediment sequence of Qikou depression, Huanghua basin was partitioned by using sequence stratigraphy theory. Each sediment sequence system mode was built. Sediment faces of subtle traps were pointed out. Dominating factors forming subtle traps were analyzed. Sandstone seismic rock physics and its response were studied in Tertiary System. Sandstone geophysical response and elastic modulus vary laws with pressure, temperature, porosity, depth were built. Experimental result and practice shows that it is possible using seismic information forecasting subtle traps. Integrated using geology, log, drilling data, special seismic processing technique, interpretation technique, high precision horizon calibration technique, 3D seismic visualizing interpretation, seismic coherence analysis, attribute analysis, logging-constrained inversion, time frequency analysis, subtle trapsobject is identified and interpreted. Finally, advantage object of subtle trap in this area was determined. Bottomland sand stratigraphic and lithologic reservoirs in Qinan slope zone have been founded by means of high resolution 3D seismic data field technique, high resolution 3D seismic data processing technique and seismic wave impendence inversion technique.

  8. Seismic hazard analysis application of methodology, results, and sensitivity studies. Volume 4

    Bernreuter, D. L


    As part of the Site Specific Spectra Project, this report seeks to identify the sources of and minimize uncertainty in estimates of seismic hazards in the Eastern United States. Findings are being used by the Nuclear Regulatory Commission to develop a synthesis among various methods that can be used in evaluating seismic hazard at the various plants in the Eastern United States. In this volume, one of a five-volume series, we discuss the application of the probabilistic approach using expert opinion. The seismic hazard is developed at nine sites in the Central and Northeastern United States, and both individual experts' and synthesis results are obtained. We also discuss and evaluate the ground motion models used to develop the seismic hazard at the various sites, analyzing extensive sensitivity studies to determine the important parameters and the significance of uncertainty in them. Comparisons are made between probabilistic and real spectral for a number of Eastern earthquakes. The uncertainty in the real spectra is examined as a function of the key earthquake source parameters. In our opinion, the single most important conclusion of this study is that the use of expert opinion to supplement the sparse data available on Eastern United States earthquakes is a viable approach for determining estimted seismic hazard in this region of the country. 29 refs., 15 tabs.

  9. Magneto--Acoustic Energetics Study of the Seismically Active Flare of 15 February 2011

    Alvarado-Gómez, J D; Martínez-Oliveros, J C; Lindsey, C; Hudson, H; Calvo-Mozo, B


    Multi--wavelength studies of energetic solar flares with seismic emissions have revealed interesting common features between them. We studied the first GOES X--class flare of the 24th solar cycle, as detected by the Solar Dynamics Observatory (SDO). For context, seismic activity from this flare (SOL2011-02-15T01:55-X2.2, in NOAA AR 11158) has been reported in the literature (Kosovichev, 2011; Zharkov et al., 2011). Based on Dopplergram data from the Helioseismic and Magnetic Imager (HMI), we applied standard methods of local helioseismology in order to identify the seismic sources in this event. RHESSI hard X-ray data are used to check the correlation between the location of the seismic sources and the particle precipitation sites in during the flare. Using HMI magnetogram data, the temporal profile of fluctuations in the photospheric line-of-sight magnetic field is used to estimate the magnetic field change in the region where the seismic signal was observed. This leads to an estimate of the work done by the...

  10. The biomechanics of running in athletes with previous hamstring injury: A case-control study.

    Daly, C; Persson, U McCarthy; Twycross-Lewis, R; Woledge, R C; Morrissey, D


    Hamstring injury is prevalent with persistently high reinjury rates. We aim to inform hamstring rehabilitation by exploring the electromyographic and kinematic characteristics of running in athletes with previous hamstring injury. Nine elite male Gaelic games athletes who had returned to sport after hamstring injury and eight closely matched controls sprinted while lower limb kinematics and muscle activity of the previously injured biceps femoris, bilateral gluteus maximus, lumbar erector spinae, rectus femoris, and external oblique were recorded. Intergroup comparisons of muscle activation ratios and kinematics were performed. Previously injured athletes demonstrated significantly reduced biceps femoris muscle activation ratios with respect to ipsilateral gluteus maximus (maximum difference -12.5%, P = 0.03), ipsilateral erector spinae (maximum difference -12.5%, P = 0.01), ipsilateral external oblique (maximum difference -23%, P = 0.01), and contralateral rectus femoris (maximum difference -22%, P = 0.02) in the late swing phase. We also detected sagittal asymmetry in hip flexion (maximum 8°, P = 0.01), pelvic tilt (maximum 4°, P = 0.02), and medial rotation of the knee (maximum 6°, P = 0.03) effectively putting the hamstrings in a lengthened position just before heel strike. Previous hamstring injury is associated with altered biceps femoris associated muscle activity and potentially injurious kinematics. These deficits should be considered and addressed during rehabilitation.

  11. Self-centering seismic retrofit scheme for reinforced concrete frame structures: SDOF system study

    Zhang, Yunfeng; Hu, Xiaobin


    This paper presents the results of a parametric study of self-centering seismic retrofit schemes for reinforced concrete (RC) frame buildings. The self-centering retrofit system features flag-shaped hysteresis and minimal residual deformation. For comparison purpose, an alternate seismic retrofit scheme that uses a bilinear-hysteresis retrofit system such as buckling-restrained braces (BRB) is also considered in this paper. The parametric study was carried out in a single-degree-of-freedom (SDOF) system framework since a multi-story building structure may be idealized as an equivalent SDOF system and investigation of the performance of this equivalent SDOF system can provide insight into the seismic response of the multi-story building. A peak-oriented hysteresis model which can consider the strength and stiffness degradation is used to describe the hysteretic behavior of RC structures. The parametric study involves two key parameters — the strength ratio and elastic stiffness ratio between the seismic retrofit system and the original RC frame. An ensemble of 172 earthquake ground motion records scaled to the design basis earthquake in California with a probability of exceedance of 10% in 50 years was constructed for the simulation-based parametric study. The effectiveness of the two seismic retrofit schemes considered in this study is evaluated in terms of peak displacement ratio, peak acceleration ratio, energy dissipation demand ratio and residual displacement ratio between the SDOF systems with and without retrofit. It is found from this parametric study that RC structures retrofitted with the self-centering retrofit scheme (SCRS) can achieve a seismic performance level comparable to the bilinear-hysteresis retrofit scheme (BHRS) in terms of peak displacement and energy dissipation demand ratio while having negligible residual displacement after earthquake.

  12. Statistical Studies of Induced and Triggered Seismicity at The Geysers, California

    Hawkins, Angela

    This study considers the statistics of induced and triggered seismicity at The Geysers geothermal field, California. Little seismicity was reported before steam extraction began in 1960. In 1980 the residual water associated with power generation was re-injected, producing induced seismicity. Beginning in 1997 large-scale injections of cold water began in order to enhance the generation of steam. This led to an increase in M 1.25 events. The GR and decay statistics will be given. However, in order to separate second-order aftershocks from triggered aftershocks, an additional triggered sequence is studied. The M = 7.2 4/4/10 Baja earthquake had some 34 M >1.25 triggered events in the first hour including a M = 3.37 event.

  13. The study of recent seismicity in the aftershock area of Neftegorsk earthquake using waveform cross correlation

    Kitov, Ivan; Turuntaev, Sergey; Konovalov, Alexei; Stepnov, Andrey


    Unusually long duration of seismic activity (more than 20 years) was observed in the aftershock area of the 1995 Neftegorsk, Sakhalin, Russia catastrophic earthquake (Ms=7.6). To study the phenomena, we have processed seismic data from 130 events occurred within that area as measured between 2006 and 2015. In order to improve the accuracy of relative location and magnitude estimation of these events we have applied new techniques based on waveform cross correlation. We use 7 three-component (3-C) seismic stations which detected most of these events. Three-component waveform templates were prepared for these stations from those events which had signals with SNR>5 at vertical channels. The events with 3 and more templates are used as master-events for waveform cross correlation. Overall, the re-estimated location and magnitudes demonstrate higher precisions and are used for the statistical analysis and numerical modelling of seismo-tectonic regime within the studied zone.

  14. Observational studies to mitigate seismic risks in mines: a new Japanese-South African collaborative research project

    Durrheim, RJ


    Full Text Available and High Stress Mining, 6-8 October 2010, Santiago CHILE 1 Observational studies to mitigate seismic risks in mines: a new Japanese - South African collaborative research project R.J. Durrheim SATREPS*, CSIR Centre for Mining Innovation... will contribute to efforts to upgrade schemes of seismic hazard assessment and to limit and mitigate the seismic risks in deep and highly stressed mines and in areas vulnerable to natural earthquakes. 2. To develop human and technical capacity in South Africa...

  15. Seismic Microzonation Study in Tabriz Metropolitan City for Earthquake Risk Mitigation x

    Ebad Ghanbari


    Full Text Available Azerbaijan is the site of convergent plate collisions along the Alpine-Himalayan active mountain belt. Brittle faults in the Azerbaijan area are mostly Cenozoic in or younger. The data presented demonstrate clearly that geological structures are commonly repeated at all scales from outcrop to regional. Several regional earthquakes have been strongly felt and caused damages in and around Tabriz during history. Urban seismic risk is increasing with population growth and encroachment of vulnerable built in environment into areas susceptible seismic hazard. Seismic -hazard assessment an estimate of ground motion at the site of interest, taking into account instrumental and historical earthquake records, information on tectonics, geology, and attenuation characteristics of seismic waves Tabriz is important industrial city of Iran. It has a very high population density about 2.000000 people in area just 90 km2 . The main objective of the Tabriz seismic instrumentation and microzonation study was to carry out and propose new building in Tabriz and suburbs in order to apply these criteria its development programs and determine the potential for damage to existing constructions during earthquake motions, and finally earthquake risk mitigation assessment.

  16. Newberry Seismic Deployment Fieldwork Report

    Wang, J; Templeton, D C


    This report summarizes the seismic deployment of Lawrence Livermore National Laboratory (LLNL) Geotech GS-13 short-period seismometers at the Newberry Enhanced Geothermal System (EGS) Demonstration site located in Central Oregon. This Department of Energy (DOE) demonstration project is managed by AltaRock Energy Inc. AltaRock Energy had previously deployed Geospace GS-11D geophones at the Newberry EGS Demonstration site, however the quality of the seismic data was somewhat low. The purpose of the LLNL deployment was to install more sensitive sensors which would record higher quality seismic data for use in future seismic studies, such as ambient noise correlation, matched field processing earthquake detection studies, and general EGS microearthquake studies. For the LLNL deployment, seven three-component seismic stations were installed around the proposed AltaRock Energy stimulation well. The LLNL seismic sensors were connected to AltaRock Energy Gueralp CMG-DM24 digitizers, which are powered by AltaRock Energy solar panels and batteries. The deployment took four days in two phases. In phase I, the sites were identified, a cavity approximately 3 feet deep was dug and a flat concrete pad oriented to true North was made for each site. In phase II, we installed three single component GS-13 seismometers at each site, quality controlled the data to ensure that each station was recording data properly, and filled in each cavity with native soil.

  17. Rancidity inhibition study in frozen whole mackerel (scomber scombrus by a previous plant extract treatment.

    Aubourg, Santiago P.


    Full Text Available The effect of flaxseeds (Linum usitatissimum on rancidity development in frozen whole mackerel (Scomber scombrus was studied. For it, fresh mackerel were dipped in flaxseeds aqueous extract during 60 min, frozen at –80 ºC during 24 hours and kept frozen (–20 ºC up to 12 months. Sampling was carried out on the initial material and at months 1, 3, 5, 7, 9 and 12 of frozen storage at –20 ºC. A parallel experiment with non treated fish was carried out in the same conditions. Rancidity development was measured by several biochemical indices (free fatty acids, peroxides, conjugated dienes and trienes, secondary oxidation products and lipoxygenase activity and complemented by the sensory analysis (skin, flesh odour, consistency and flesh appearance. As a result of the previous antioxidant treatment, peroxides showed to breakdown faster (pSe ha estudiado el efecto del lino (Linum usitatissimum en el desarrollo de rancidez en caballa entera congelada (Scomber scombrus. Para ello, caballas frescas fueron sumergidas en extractos acuosos de semillas de lino durante 60 min, congeladas a -80 ºC durante 24 h y mantenidas congeladas ( -20 ºC durante 12 meses. Se tomaron muestras del material inicial y tras 1, 3, 5, 7, 9 y 12 meses de congelación a -20 ºC . Un experimento paralelo con pescado no tratado fue llevado acabo en las mismas condiciones. El desarrollo de la rancidez fue medido por varios índices bioquímicos (ácidos grasos libres, peróxidos, dienos y trienos conjugados, productos secundarios de oxidación y actividad lipoxigenasa y completado con análisis sensorial (piel, olor de la carne, consistencia y apariencia de la carne. Como resultado del tratamiento antioxidante, los peróxidos se degradaron más rápidos (p < 0.05 después del mes 7, y por tanto, contenidos mayores (p < 0.05 de dienos y trienos conjugados pudieron ser detectados en el pescado tratado. El tratamiento antioxidante también condujo a un

  18. Integrated study of geophysical and biological anomalies before earthquakes (seismic and non-seismic), in Austria and Indonesia

    Straka, Wolfgang; Assef, Rizkita; Faber, Robert; Ferasyi, Reza


    Earthquakes are commonly seen as unpredictable. Even when scientists believe an earthquake is likely, it is still hard to understand the indications observed, as well as their theoretical and practical implications. There is some controversy surrounding the concept of using animals as a precursor of earthquakes. Nonetheless, several institutes at University of Natural Resources and Life Sciences, and Vienna University of Technology, both Vienna, Austria, and Syiah Kuala University, Banda Aceh, as well as Terramath Indonesia, Buleleng, both Indonesia, cooperate in a long-term project, funded by Red Bull Media House, Salzburg, Austria, which aims at getting some decisive step forward from anecdotal to scientific evidence of those interdependencies, and show their possible use in forecasting seismic hazard on a short-term basis. Though no conclusive research has yet been published, an idea in this study is that even if animals do not respond to specific geophysical precursors and with enough notice to enable earthquake forecasting on that basis, they may at least enhance, in conjunction with other indications, the degree of certainty we can get of a prediction of an impending earthquake. In Indonesia, indeed, before the great earthquakes of 2004 and 2005, ominous geophysical as well as biological phenomena occurred (but were realized as precursors only in retrospect). Numerous comparable stories can be told from other times and regions. Nearly 2000 perceptible earthquakes (> M3.5) occur each year in Indonesia. Also, in 2007, the government has launched a program, focused on West Sumatra, for investigating earthquake precursors. Therefore, Indonesia is an excellent target area for a study concerning possible interconnections between geophysical and biological earthquake precursors. Geophysical and atmospheric measurements and behavioral observation of several animal species (elephant, domestic cattle, water buffalo, chicken, rat, catfish) are conducted in three areas

  19. Seismicity studies at Moluccas area based on the result of hypocenter relocation using HypoDD

    Utama, Muhammad Reza July; Nugraha, Andri Dian; Puspito, Nanang T.


    The precise hypocenter was determined location using double difference method around subduction zone in Moluccas area eastern part of Indonesia. The initial hypocenter location from MCGA data catalogue of 1,945 earthquake events. Basically the principle of double-difference algorithm assumes if the distance between two earthquake hypocenter distribution is very small compared to the distance between the station to the earthquake source, the ray path can be considered close to both earthquakes. The results show the initial earthquakes with a certain depth (fix depth 10 km) relocated and can be interpreted more reliable in term of seismicity and geological setting. The relocation of the intra slab earthquakes beneath Banda Arc are also clearly observed down to depth of about 400 km. The precise relocated hypocenter will give invaluable seismicity information for other seismological and tectonic studies especially for seismic hazard analysis in this region.

  20. Seismicity studies at Moluccas area based on the result of hypocenter relocation using HypoDD

    Utama, Muhammad Reza July, E-mail: [Student of Geophysical Engineering Study Program, Institute of Technology Bandung (Indonesia); Indonesian Meteorological, Climatological and Geophysical Agency (MCGA), Jakarta (Indonesia); Nugraha, Andri Dian; Puspito, Nanang T. [Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, ITB (Indonesia)


    The precise hypocenter was determined location using double difference method around subduction zone in Moluccas area eastern part of Indonesia. The initial hypocenter location from MCGA data catalogue of 1,945 earthquake events. Basically the principle of double-difference algorithm assumes if the distance between two earthquake hypocenter distribution is very small compared to the distance between the station to the earthquake source, the ray path can be considered close to both earthquakes. The results show the initial earthquakes with a certain depth (fix depth 10 km) relocated and can be interpreted more reliable in term of seismicity and geological setting. The relocation of the intra slab earthquakes beneath Banda Arc are also clearly observed down to depth of about 400 km. The precise relocated hypocenter will give invaluable seismicity information for other seismological and tectonic studies especially for seismic hazard analysis in this region.

  1. Study of Gutenberg-Richter coefficients considering time evolution for different mexican seismic regions

    Carrizales Velazquez, Carlos; Angulo Brown, Fernando


    In the present work, we propose a division of the Mexican Pacific coast and we study the time evolution of the Gutenberg-Richter coefficients ("a" and "b" values) along the 2006-2016 period by means of the sliding time window method. We observed that the sequences of a and b values obtained, are positively correlated as it must be, because otherwise it would represent a seismic dynamics incompatible with a self-organized critical system "the earth crust". Furthermore, we analyze the variation of the modal value "a/b" showing be a better estimator of seismic activity that only a or b parameters. Finally, we perform size window variation analysis to keep constant the seismic energy released by N-events into the time window.

  2. Study on the Characteristics of Seismic Activity in West China and Its neighboring Regions

    Chen Yuwei; Shen Yelong; Ling Xueshu


    The controlling and influencing effects of the joint action of plates surrounding China on strong earthquakes in Chinese mainland are discussed, and the characteristics of seismic activities in the West of China and neighboring regions are further studied. The results show that the seismic activity in the West of China and neighboring regions not only has the characteristics of high tide and low tide alternation but also has the characteristics of rising in one region while falling in another, and the rise and fail of seismicity are in some proportion. The above characteristics are useful for the prediction of main body region of strong earthquakes in Chinese mainland, especially for the judgement of the ending time of the high fide period.

  3. Integrated modeling and field study of potential mechanisms forinduced seismicity at The Geysers Goethermal Field, California

    Rutqvist, Jonny; Majer, Ernie; Oldenburg, Curt; Peterson, John; Vasco, Don


    In this paper, we present progress made in a study aimed atincreasing the understanding of the relative contributions of differentmechanisms that may be causing the seismicity occurring at The Geysersgeothermal field, California. The approach we take is to integrate: (1)coupled reservoir geomechanical numerical modeling, (2) data fromrecently upgraded and expanded NCPA/Calpine/LBNL seismic arrays, and (3)tens of years of archival InSAR data from monthly satellite passes. Wehave conducted a coupled reservoir geomechanical analysis to studypotential mechanisms induced by steam production. Our simulation resultscorroborate co-locations of hypocenter field observations of inducedseismicity and their correlation with steam production as reported in theliterature. Seismic and InSAR data are being collected and processed foruse in constraining the coupled reservoir geomechanicalmodel.

  4. Analytical Study on the Beyond Design Seismic Capacity of Reinforced Concrete Shear Walls

    Nugroho, Tino Sawaldi Adi [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Chi, Ho-Seok [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)


    The OECD-NEA has organized an international benchmarking program to better understand this critical issue. The benchmark program provides test specimen geometry, test setup, material properties, loading conditions, recorded measures, and observations of the test specimens. The main objective of this research is to assess the beyond design seismic capacity of the reinforced concrete shear walls tested at the European Laboratory for Structural Assessment between 1997 and 1998 through participation in the OECD-NEA benchmark program. In this study, assessing the beyond design seismic capacity of reinforced concrete shear walls is performed analytically by comparing numerical results with experimental results. The seismic shear capacity of the reinforced concrete shear wall was predicted reasonably well using ABAQUS program. However, the proper calibration of the concrete material model was necessary for better prediction of the behavior of the reinforced concrete shear walls since the response was influenced significantly by the material constitutive model.

  5. ECHO Project: a series of tools for studying and characterizing seismic sequences evolution

    Falcone, Giuseppe; De Santis, Angelo; Di Giovambattista, Rita; Cianchini, Gianfranco; Murru, Maura; Calderoni, Giovanna; Lucente, Pio Francesco; De Gori, Pasquale; Frepoli, Alberto; Signanini, Patrizio; Rainone, Mario; Vessia, Giovanna


    One of the most ubiquitous problems in seismology is to discriminate between seismic sequences (a series of small-to-moderate earthquakes that culminate with a mainshock) and swarms (diffuse seismicity w/o mainshock), that can be easily done only after a certain class of earthquakes have occurred. We propose to put these phenomena under the same framework provided by the geosystemics (De Santis, 2009, 2014), where the planet Earth and its processes are seen from a holistic point of view, and the New Geophysics (Crampin et al., 2013), where fluid-saturated microcracks in almost all crustal rocks are so closely-spaced they verge on failure and hence are highly-compliant critical systems (Signanini and De Santis, 2012). In this context, nonlinear concepts typical of Chaos and Information theories are fundamental to study and characterize the various features of the series of seismic events, and, eventually, to discriminate between seismic sequences and swarms. The two theories imply the use of non-linear techniques which are innovative in seismology. The project ECHO ("Entropy and CHaOs: tools for studying and characterizing seismic sequences evolution"), a recent INGV-funded project, would aim at applying the above approaches in a more integrated way mainly to establish a suite of effective tools to disclose and characterise the principal features of the series of earthquakes which are of interest. In our view this will represent the very first step before to face the more challenging (but longer-term) problem of discriminating between the two kinds of series of seismic events. This poster will describe these kinds of preliminary activities and relative results in the framework of the project.

  6. Effect of Previous Irradiation on Vascular Thrombosis of Microsurgical Anastomosis: A Preclinical Study in Rats.

    Barrera-Ochoa, Sergi; Gallardo-Calero, Irene; López-Fernández, Alba; Romagosa, Cleofe; Vergés, Ramona; Aguirre-Canyadell, Marius; Soldado, Francisco; Velez, Roberto


    The objective of the present investigation was to compare the effect of neoadjuvant irradiation on the microvascular anastomosis in cervical bundle using an experimental model in rats. One hundred forty male Sprague-Dawley rats were allocated into 4 groups: group I, control, arterial microanastomosis; group II, control, venous microanastomosis; group III, arterial microanastomosis with previous irradiation (20 Gy); and group IV, venous microanastomosis with previous irradiation (20 Gy). Clinical parameters, technical values of anastomosis, patency, and histopathological parameters were evaluated. Irradiated groups (III and IV) and vein anastomosis groups (II and IV) showed significantly increased technical difficulties. Group IV showed significantly reduced patency rates (7/35) when compared with the control group (0/35). Radiotherapy significantly decreased the patency rates of the vein (7/35) when compared with the artery (1/35). Groups III and IV showed significantly reduced number of endothelial cells and also showed the presence of intimal thickening and adventitial fibrosis as compared with the control group. Neoadjuvant radiotherapy reduces the viability of the venous anastomosis in a preclinical rat model with a significant increase in the incidence of vein thrombosis.

  7. Preliminary seismic hazard assessment, shallow seismic refraction and resistivity sounding studies for future urban planning at the Gebel Umm Baraqa area, Egypt

    Khalil, Mohamed H.; Hanafy, Sherif M.; Gamal, Mohamed A.


    Gebel Umm Baraqa Fan, west Gulf of Aqaba, Sinai, is one of the most important tourism areas in Egypt. However, it is located on the active Dead Sea-Gulf of Aqaba Levant transform fault system. Geophysical studies, including fresh water aquifer delineation, shallow seismic refraction, soil characterization and preliminary seismic hazard assessment, were conducted to help in future city planning. A total of 11 vertical electrical soundings (1000-3000 m maximum AB/2) and three bore-holes were drilled in the site for the analysis of ground water, total dissolved solids (TDS) and fresh water aquifer properties. The interpretation of the one-dimensional (1D) inversion of the resistivity data delineated the fresh water aquifer and determined its hydro-geologic parameters. Eleven shallow seismic refraction profiles (125 m in length) have been collected and interpreted using the generalized reciprocal method, and the resulting depth-velocity models were verified using an advanced finite difference (FD) technique. Shallow seismic refraction effectively delineates two subsurface layers (VP ~ 450 m s-1 and VP ~ 1000 m s-1). A preliminary seismic hazard assessment in Umm Baraqa has produced an estimate of the probabilistic peak ground acceleration hazard in the study area. A recent and historical earthquake catalog for the time period 2200 BC to 2006 has been compiled for the area. New accurate seismic source zoning is considered because such details affect the degree of hazard in the city. The estimated amount of PGA reveals values ranging from 250 to 260 cm s-2 in the bedrock of the Umm Baraqa area during a 100 year interval (a suitable time window for buildings). Recommendations as to suitable types of buildings, considering the amount of shaking and the aquifer properties given in this study, are expected to be helpful for the Umm Baraqa area.

  8. Evaluation and assessment of nuclear power plant seismic methodology

    Bernreuter, D.; Tokarz, F.; Wight, L.; Smith, P.; Wells, J.; Barlow, R.


    The major emphasis of this study is to develop a methodology that can be used to assess the current methods used for assuring the seismic safety of nuclear power plants. The proposed methodology makes use of system-analysis techniques and Monte Carlo schemes. Also, in this study, we evaluate previous assessments of the current seismic-design methodology.

  9. Preliminary Study of m(b) Bias at Selected Soviet Seismic Stations.


    8217-R66 395 PRELIMINARY STUDY OF M(B) BIRS AT SELECTED SOVIET 1/1 SEISMIC STRTIONS(U) SCIENCE APPLICATIONS INTERNATIONAL CORP ARLINGTON VR A S RYRLL...earthquakes in each source region was not given in the ,.t 1980 paper, but in the earlier work it ranged from 35 events for Asia and the Mediter - ranean to

  10. The Lima-Peru seismic gap: a study of inter-seismic strain accumulation from a decade of GPS measurements

    Norabuena, E. O.; Pollitz, F. F.; Dixon, T. H.


    The Peruvian subduction zone between the Mendaña Fracture zone and Arica, northern Chile, has been source of large megathrust earthquakes since historical to present times, The two last major events affecting the southern segment corresponds to Arequipa 2001 (Mw 8.3) and Pisco 2007 (Mw 8.1). A noteworthy event is the Lima 1746 earthquake with an assigned magnitude of Mw 8.5 and which is assumed to have broken several km of the seismogenic zone off Lima. The great shock was followed by a devastating tsunami that destroyed the main port of Callao, killing about 99 percent of its population. This extreme event was followed by quiescence of a few hundred years until the XX century when the Lima subduction zone was broken again by the earthquakes of May 1940 (Mw 8.0), October 1966 (Mw 8.0) and Lima 1974 (Mw 8.0). The broken areas overlap partially with the estimated area of the 1746 earthquake and put the region in a state of seismic gap representing a major hazard for Lima city - Peru's capital and its about 9 million of inhabitants. Our study reports the interseismic strain accumulation derived from a decade of GPS measurement at 11 geodetic monuments including one measurement in an island 80 km offshore and models variations of coupling along the plate interface.

  11. Seismic anisotropy beneath the Mississippi Embayment and the New Madrid Seismic Zone: A study of shear wave splitting

    Nyamwandha, Cecilia A.; Powell, Christine A.


    Shear wave splitting associated with the Mississippi Embayment (ME) is determined using teleseismic SKS phases recorded by the Northern Embayment Lithosphere Experiment (NELE), the USArray Transportable Array (TA), and the New Madrid seismic network for the period 2005-2016. Our data set consists of 5900 individual splitting measurements from 257 earthquakes recorded at 151 stations within and outside the ME. Stations outside of the ME exhibit significant shear wave splitting, with average delay times between 0.4 s and 1.8 s. To the northeast and east of the ME, nearly all observed fast orientations are approximately oriented northeast-southwest, in agreement with absolute plate motion (APM) predicted by HS3-Nuvel-1A. The homogeneity of the fast orientations in this region suggests that the splitting is due to active flow in the asthenosphere. A counterclockwise rotation in the splitting orientation is observed moving northeast to northwest across the study area. Inside the ME, some stations show large and systematic deviations of the measured fast orientations from the APM. The delay times within the entire ME range from 0.9 s to 2.1 s. Splitting complexity is attributed to relic lithospheric fabrics formed during past tectonic events including passage of a hot spot in mid-Cretaceous time. The anisotropy may also be linked to the presence of a southwest dipping region of low P and S wave velocities below the ME or to deeper flow in the asthenosphere.

  12. Experimental study on the seismic response of braced reinforced concrete frame with irregular columns

    Xiao, Jianzhuang; Li, Jie; Chen, Jun


    A 15-storey K-braced reinforced concrete model frame with irregular columns, i.e., T-shaped, L-shaped, as well as +-shaped columns, was constructed and tested on the six-degree-of-freedom shaking table at the State Key Laboratory for Disaster Reduction in Civil Engineering in Tongji, China. Two types of earthquake records, El-Centro wave (south-north direction) and Shanghai artifi cial wave (SHAW) with various peak accelerations and principal-secondary sequences, were input and experimentally studied. Based on the shaking table tests and theoretical analysis, several observations can be made. The failure sequence of the model structure is brace→beam→column→joints, so that the design philosophy for several lines of defense has been achieved. Earthquake waves with different spectrums not only infl uence the magnitude and distribution of the earthquake force and the storey shear force, but also obviously affect the magnitude of the displacement response. The aftershock seismic response of previously damaged reinforced concrete braced frames with irregular columns possesses the equivalent elastic performance characteristic. Generally speaking, from the aspects of failure features and drift ratio, this type of reinforced concrete structure provides adequate earthquake resistance and can be promoted for use in China.

  13. Study of Seismic Activity Using Geophysical and Radio Physical Equipment for Observation

    Kvavadze, N.; Tsereteli, N. S.


    One of the most dangerous and destructive natural hazards are earthquakes, which is confirmed by recent earthquakes such as Nepal 2015, Japan and Turkey 2011. Because of this, study of seismic activity is important. Studying any process, it is necessary to use different methods of observation, which allows us to increase accuracy of obtained data. Seismic activity is a complex problem and its study needs different types of observation methods. Two main problems of seismic activity study are: reliable instrumental observations and earthquake short-term predictions. In case of seismic risks it is necessary to have reliable accelerometer data. One of the most promising field in earthquake short-term prediction is very low frequency (VLF) electromagnetic wave propagation in ionosphere observation. To study Seismic activity of Caucasus region, was created observation complex using Accelerometer, Velocimeter and VLF electromagnetic waves received from communication stations (located in different area of the world) reflected from low ionosphere. System is created and operates at Tbilisi State University Ionosphere Observatory, near Tbilisi in Tabakhmela 42.41'70 N, 44.80'92 E, Georgia. Data obtained is sent to a local server located at M. Nodia Institute of Geophysics, TSU, for storage and processing. Diagram for complex is presented. Also data analysis methods were created and preliminary processing was done. In this paper we present some of the results: Earthquake data from ionosphere observations as well as local earthquakes recorded with accelerometer and velocimeter. Complex is first in 6 that will be placed around Georgia this year. We plan on widening network every year.

  14. An extensive study of clustering features of seismicity in Italy during 2005 to 2016

    Zhuang, Jiancang; Guo, Yicun; Murru, Maura; Falcone, Giuseppe; Taroni, Matteo; Console, Rodolfo


    Compiled by INGV, the ISIDE catalog includes high quality recorders of the occurrence times, locations, and magnitude of earthquakes that occurred in the Italy region since 2005-4-16. To study the characteristics of seismicity in Italy, we use the space-time ETAS model and several extended forms. Our results show: 1. Seismicity clustering features are quite different from region to region. According to the ETAS parameters, the whole study region can be divided into four subregions. 2. The rupture geometries of large earthquakes, including the 2009-4-6 M6.3 L'Aquila, the 2012-5-20 M6.1 Emilia, the 2016-0-24 M6.0 Amatrice, the 2016-10-30 M6.2 Norcia earthquakes, control the spatial locations of their direct aftershocks. These direct aftershock aftershock mainly concentrate near, some parts close to the parts on the rupture plane with large slips but seldom overlap with them, indicating that aftershocks are the continuation of the rupture process of the mainshocks. 3. When the focal depth is considered in seismicity modeling, improved probability forecasting of seismicity and hazard assessment can be obtained.

  15. Seismic wave propagation modeling in porous media for various frequencies: A case study in carbonate rock

    Nurhandoko, Bagus Endar B.; Wardaya, Pongga Dikdya; Adler, John; Siahaan, Kisko R.


    Seismic wave parameter plays very important role to characterize reservoir properties whereas pore parameter is one of the most important parameter of reservoir. Therefore, wave propagation phenomena in pore media is important to be studied. By referring this study, in-direct pore measurement method based on seismic wave propagation can be developed. Porosity play important role in reservoir, because the porosity can be as compartment of fluid. Many type of porosity like primary as well as secondary porosity. Carbonate rock consist many type of porosity, i.e.: inter granular porosity, moldic porosity and also fracture porosity. The complexity of pore type in carbonate rocks make the wave propagation in these rocks is more complex than sand reservoir. We have studied numerically wave propagation in carbonate rock by finite difference modeling in time-space domain. The medium of wave propagation was modeled by base on the result of pattern recognition using artificial neural network. The image of thin slice of carbonate rock is then translated into the velocity matrix. Each mineral contents including pore of thin slice image are translated to velocity since mineral has unique velocity. After matrix velocity model has been developed, the seismic wave is propagated numerically in this model. The phenomena diffraction is clearly shown while wave propagates in this complex carbonate medium. The seismic wave is modeled in various frequencies. The result shows dispersive phenomena where high frequency wave tends to propagate in matrix instead pores. In the other hand, the low frequency waves tend to propagate through pore space even though the velocity of pore is very low. Therefore, this dispersive phenomena of seismic wave propagation can be the future indirect measurement technology for predicting the existence or intensity of pore space in reservoir rock. It will be very useful for the future reservoir characterization.

  16. Study of Seismic Clusters at Bahía de Banderas Region, Mexico

    Nunez-Cornu, F. J.; Rutz-Lopez, M.; Suarez-Plascencia, C.; Trejo-Gomez, E.


    Given that the coast in the states of Jalisco and south of the state of Nayarit is located within a region of high seismic potential and also because population is increasing, perhaps motivated by the development of tourism, the Civil Defense authorities of Jalisco and the Centro de Sismología y Volcanología de Occidente-SisVOc of Universidad de Guadalajara started in the year 2000 a joint project to study the seismic risk of the region, including the seismic monitoring of Colima volcano (located between the states of Jalisco and Colima). This work focuses on the study of seismicity in the area of Bahía de Banderas and northern coast of Jalisco. To this end, we perform an analysis of available seismograms to characterize active structures, their relationship to surface morphology, and possible reach of these structures into the shallow parts of the bay. The data used in this work are waveforms recorded during the year 2003 during which the seismograph network spanned the region of study. Our method is based on the identification of seismic clusters or families using cross-correlation of waveforms, earthquake relocation and modeling of fault planes. From an initial data set of 404 earthquakes located during 2003, 96 earthquakes could be related to 17 potentially active continental structures. A modeling of fault planes was possible for 11 of these structures. Subgroups of 7 structures are aligned parallel to the Middle America Trench, a possible consequence of oblique subduction. The magnitudes of earthquakes grouped into families is less than 3.6 (Ml), corresponding to fault dimensions of hundreds of meters.

  17. Experimental study of seismic cyclic loading effects on small strain shear modulus of saturated sands

    ZHOU Yan-guo; CHEN Yun-min; HUANG Bo


    The seismic loading on saturated soil deposits induces a decrease in effective stress and a rearrangement of the soil-particle structure, which may both lead to a degradation in undrained stiffness and strength of soils. Only the effective stress influence on small strain shear modulus Gmax is considered in seismic response analysis nowadays, and the cyclic shearing induced fabric changes of the soil-particle structure are neglected. In this paper, undrained cyclic triaxial tests were conducted on saturated sands with the shear wave velocity measured by bender element, to study the influences of seismic loading on Gmax. And Gmax of samples without cyclic loading effects was also investigated for comparison. The test results indicated that Gmax under cyclic loading effects is lower than that without such effects at the same effective stress, and also well correlated with the effective stress variation. Hence it is necessary to reinvestigate the determination of Gmax in seismic response analysis carefully to predict the ground responses during earthquake more reasonably.

  18. Increasing signal-to-noise ratio of marine seismic data: A case study from offshore Korea

    Kim, Taeyoun; Jang, Seonghyung


    Subsurface imaging is difficult without removing the multiples intrinsic to most marine seismic data. Choosing the right multiple suppression method when working with marine data depends on the type of multiples and sometimes involves trial and error. A major amount of multiple energy in seismic data is related to the large reflectivity of the surface. Surface-related multiple elimination (SRME) is effective for suppressing free-surface-related multiples. Although SRME has some limitations, it is widely used because it requires no assumptions about the subsurface velocities, positions, and reflection coefficients of the reflector causing the multiples. The common reflector surface (CRS) stacking technique uses CRS reflectors rather than common mid-point (CMP) reflectors. It stacks more traces than conventional stacking methods and increases the signal-to-noise ratio. The purpose of this study is to address a process issue for multiple suppression with SRME and Radon filtering, and to increase the signal-to-noise ratio by using CRS stacking on seismic data from the eastern continental margin of Korea. To remove free surface multiples, SRME and Radon filtering are applied to attenuate the interbed multiples. Results obtained using synthetic data and field data show that the combination of SRME and Radon filtering is effective for suppressing free-surface multiples and peg-leg multiples. Applying CRS stacking to seismic data in which multiples have been eliminated increases the signal-to-noise ratio for the area examined, which is being considered for carbon dioxide capture and storage.

  19. Study on Fluid-Lining-Rock Coupling Interaction of Diversion Tunnel under Seismic Load

    Jian Deng


    Full Text Available Fluid-lining-rock coupling interaction of diversion tunnel under seismic load is a critical problem in seismic research which should be solved urgently. Based on the explicit finite element method for dynamic analysis of single-phase fluid and solid medium and combining with the boundary conditions of coupling interface, a dynamic explicit finite element solving format of diversion tunnel considering fluid-lining coupling interaction is established. In light of the basic theory of dynamic contact force method and applying the nonlinear hyperbolic constitutive model of contact surface, a dynamic explicit finite element time-domain integral equation of combined bearing of lining and surrounding rocks, which takes the bond-slip behavior of the contact surface into account, is put forward. Meanwhile, considering the dynamic interaction process of inner water and lining, lining and surrounding rocks, an explicit finite element numerical simulation analysis method of fluid-lining-rock coupling interaction of diversion tunnel under seismic load is presented. The calculation results of case study reasonably reflect the seismic response characteristics of diversion tunnel, and an effective analysis method is provided for the aseismic design of hydraulic tunnel.

  20. Convergence in the Bilingual Lexicon: A Pre-registered Replication of Previous Studies

    White, Anne; Malt, Barbara C.; Storms, Gert


    Naming patterns of bilinguals have been found to converge and form a new intermediate language system from elements of both the bilinguals’ languages. This converged naming pattern differs from the monolingual naming patterns of both a bilingual’s languages. We conducted a pre-registered replication study of experiments addressing the question whether there is a convergence between a bilingual’s both lexicons. The replication used an enlarged set of stimuli of common household containers, providing generalizability, and more reliable representations of the semantic domain. Both an analysis at the group-level and at the individual level of the correlations between naming patterns reject the two-pattern hypothesis that poses that bilinguals use two monolingual-like naming patterns, one for each of their two languages. However, the results of the original study and the replication comply with the one-pattern hypothesis, which poses that bilinguals converge the naming patterns of their two languages and form a compromise. Since this convergence is only partial the naming pattern in bilinguals corresponds to a moderate version of the one-pattern hypothesis. These findings are further confirmed by a representation of the semantic domain in a multidimensional space and the finding of shorter distances between bilingual category centers than monolingual category centers in this multidimensional space both in the original and in the replication study. PMID:28167921

  1. Randomized phase 2 study of obinutuzumab monotherapy in symptomatic, previously untreated chronic lymphocytic leukemia.

    Byrd, John C; Flynn, Joseph M; Kipps, Thomas J; Boxer, Michael; Kolibaba, Kathryn S; Carlile, David J; Fingerle-Rowson, Guenter; Tyson, Nicola; Hirata, Jamie; Sharman, Jeff P


    Obinutuzumab is a glycoengineered, type 2 anti-CD20 humanized antibody with single-agent activity in relapsed chronic lymphocytic leukemia (CLL). With other CD20 antibodies, a dose-response relationship has been shown. We therefore performed a randomized phase 2 study in symptomatic, untreated CLL patients to evaluate if an obinutuzumab dose response exists. Obinutuzumab was given at a dose of 1000 mg (100 mg IV day 1, 900 mg day 2, 1000 mg day 8 and day 15 of cycle 1; 1000 mg day 1 of cycles 2-8) or 2000 mg (100 mg IV day 1, 900 mg day 2, 1000 mg day 3, 2000 mg day 8 and day 15 of cycle 1; 2000 mg day 1 of cycles 2-8). The primary end point was overall response rate (ORR). Eighty patients were enrolled with similar demographics: median age 67 years, 41% high-risk Rai disease, and 10% del(17p)(13.1). ORR (67% vs 49%, P = .08) and complete response (CR) or CR with incomplete cytopenia response (20% vs 5%) favored 2000 mg obinutuzumab. Overall, therapy was well tolerated, and infusion events were manageable. This study demonstrates significant efficacy of obinutuzumab monotherapy, for 1000 mg as well as for 2000 mg, in untreated CLL patients with acceptable toxicity. Although exploratory, a dose-response relationship may exist, but its relevance to improving progression-free survival is uncertain and will require further follow-up. This trial was registered at as #NCT01414205.




    Full Text Available With the world - wide rising trend of caesarean delivery (CD, modern obstetric practice deals with a new group of mothers carrying reproductive performance upon a scarred uterus with obvious risk in feto - maternal outcome. AIMS: (1 To analyse the maternal & neonatal outcome in post - caesarean pregnancy. (2 To evaluate the factors influencing outcome in such cases. Design : Observational analytical study. MATERIALS & METHODS: The present study was carried out over two years (2010 - 11 taking consecutive 100 p ost - caesarean cases as admitted on my admission days & delivered in BR Singh Hospital. Data collection was done by interview technique along with hospital records. ANALYSIS USED: Percentage analysis was most often done. Categorical variables were compared with chi - square test; P value was calculated with 2012 Graphpad Software. Relative risk (RR & Odd ratio (OR were calculated with 1993 - 2012 Medcalc Software bvba (Version 12.3.0. All statistical tests were evaluated at the 0.05 significance level. RESULT S: Post - caesarean pregnancy rate was 26.02%. Vaginal birth after caesarean (VBAC incidence was 22% whereas VBAC success on trial of labour was 55%. VBAC gave best morbidity outcome (18.18% & 27.27%. But failed VBAC cases result more significant maternal morbidity (RR=3.97, P=0.0037 & NICU admission was also found highest in failed VBAC cases (38.89%. Maternal and neonatal morbidity were significantly high when scar integrity was lost; also significantly co - related with elderly mothers (>35 yrs., un - boo ked cases & non - admitted cases undergone repeat CD. CONCLUSIONS: Post - caesarean cases need meticulous antenatal check - up & mandatory institutional delivery with proper selection of mode of confinement to have a better maternal & neonatal outcome

  3. Study of Channel Morphology and Infill Lithology in the Wilcox Group Central Louisiana Using Seismic Attribute Analysis

    Chen, Feng

    The fluvial and deltaic Wilcox Group is a major target for hydrocarbon and coal exploration in northern and central Louisiana. However, the characterization and delineation of fluvial systems is a difficult task due to the variability and complexity of fluvial systems and their internal heterogeneities. Seismic geomorphology is studied by recognizing paleogeographic features in seismic stratal slices, which are seismic images of paleo-depositional surfaces. Seismic attributes, which are extracted along seismic stratal slices, can reveal information that is not readily apparent in raw seismic data. The existence and distribution of fluvial channels are recognized by the channel geomorphology in seismic attributes displayed on stratal slices. The lithologies in the channels are indicated by those seismic attributes that are directly related to the physical properties of rocks. Selected attributes utilized herein include similarity, spectral decomposition, sweetness, relative acoustic impedance, root mean square (RMS) amplitude, and curvature. Co-rendering and Red/Green/Blue (RGB) display techniques are also included to better illuminate the channel geometry and lithology distribution. Hydrocarbons may exist in the channel sand-bodies, but are not explicitly identified herein. Future drilling plans for oil and gas exploration may benefit from the identification of the channels and the lithologies that fill them.

  4. Numerical investigation of topographic effects in seismic wave amplification: Northern Chile Coastal Cliff as study case.

    García-Pérez, T.; Ferreira, A. M.; Yanez, G. A.; Cembrano, J. M.


    The Coastal Cliff (CC) of Northern Chile is a first-order Andean geomorphological feature running parallel to trench. With an average elevation of 1 km and a length of 800 km, it represents the western limit of the Coastal Range. Several cities and industrial facilities are located in the vicinity of the CC. Site effects were documented in Alto Hospicio, Huara and Pozo Almonte towns during the Mw 8.2 Pisagua earthquake on the 1st April of 2014, all of which are located close or at the CC. These site effects were not predicted by the Vs30 seismic microzonation previously carried out in the area. Topographic effects arising from the CC topography could be responsible for these site effects. To understand the role of the topography on seismic amplification during an earthquake, we will simulate seismic wave propagation in an elastic media with complex topography using the spectral element method (SPECFEM3D Cartesian package). Preliminary results obtained from simple 2D models, show amplifications related to the topography in the three seismic components, but with more significant amplifications in the vertical component, for high frequencies. To assess the possible topographic amplification in the Coastal Cliff in Northern Chile, improvements to the simple models considered will be discussed. Through the inclusion of a more detailed mesh including relevant geological observations and geophysically-derived petrophysical and depth-projected features, we shall analyses high frequency waveform (up to 1.5 Hz), to more accurately represent the complexity of the effects of topography and distinguish it from those of subsurface structure.

  5. Life cycle impact assessment of ammonia production in Algeria: A comparison with previous studies

    Makhlouf, Ali, E-mail:; Serradj, Tayeb; Cheniti, Hamza


    In this paper, a Life Cycle Analysis (LCA) from “cradle to gate” of one anhydrous ton of ammonia with a purity of 99% was achieved. Particularly, the energy and environmental performance of the product (ammonia) were evaluated. The eco-profile of the product and the share of each stage of the Life Cycle on the whole environmental impacts have been evaluated. The flows of material and energy for each phase of the life cycle were counted and the associated environmental problems were identified. Evaluation of the impact was achieved using GEMIS 4.7 software. The primary data collection was executed at the production installations located in Algeria (Annaba locality). The analysis was conducted according to the LCA standards ISO 14040 series. The results show that Cumulative Energy Requirement (CER) is of 51.945 × 10{sup 3} MJ/t of ammonia, which is higher than the global average. Global Warming Potential (GWP) is of 1.44 t CO{sub 2} eq/t of ammonia; this value is lower than the world average. Tropospheric ozone precursor and Acidification are also studied in this article, their values are: 549.3 × 10{sup −6} t NMVOC eq and 259.3 × 10{sup −6} t SO{sub 2} eq respectively.

  6. Experimental bluetongue virus infection of sheep; effect of previous vaccination: clinical and immunologic studies.

    Mahrt, C R; Osburn, B I


    Clinical and immunologic responses of sheep to vaccination and subsequent bluetongue virus (BTV) challenge exposure were studied and compared with those of non-vaccinated sheep. Sheep were vaccinated with inactivated BTV administered with aluminum hydroxide and cimetidine or levamisole. After sheep were vaccinated, precipitating group-specific antibodies to BTV were detected, but serotype-specific neutralizing antibodies were not detected. Cellular immune responses (lymphocyte blastogenesis) to BTV were not detected. After virulent BTV challenge exposure, vaccinated and nonvaccinated sheep developed acute clinical disease of similar severity. Clinical signs included hyperemia and petechiae of oral mucosa and coronary bands of the feet, excess salivation, nasal discharge with crusting, ulceration of the muzzle, and edema of lips and intermandibular space. Marked increases in serum creatine kinase activity were associated with stiff gait, reluctance to move, and vomiting. Fever and leukopenia were detected in most of the challenge-exposed sheep. Viremia and neutralizing antibodies were detected in vaccinated and nonvaccinated sheep after challenge exposure. Bluetongue virus-specific reaginic antibodies were not detected in sera from any of the sheep when the passive cutaneous anaphylaxis test was used.

  7. Experimental study on impact-induced seismic wave propagating through quartz sand simulating asteroid regolith

    Matsue, Kazuma; Arakawa, Masahiko; Yasui, Minami; Matsumoto, Rie; Tsujido, Sayaka; Takano, Shota; Hasegawa, Sunao


    Introduction: Recent spacecraft surveys clarified that asteroid surfaces were covered with regolith made of boulders and pebbles such as that found on the asteroid Itokawa. It was also found that surface morphologies of asteroids formed on the regolith layer were modified. For example, the high-resolution images of the asteroid Eros revealed the evidence of the downslope movement of the regolith layer, then it could cause the degradation and the erasure of small impact crater. One possible process to explain these observations is the regolith layer collapse caused by seismic vibration after projectile impacts. The impact-induced seismic wave might be an important physical process affecting the morphology change of regolith layer on asteroid surfaces. Therefore, it is significant for us to know the relationship between the impact energy and the impact-induced seismic wave. So in this study, we carried out impact cratering experiments in order to observe the seismic wave propagating through the target far from the impact crater.Experimental method: Impact cratering experiments were conducted by using a single stage vertical gas gun set at Kobe Univ and a two-stage vertical gas gun set at ISAS. We used quartz sands with the particle diameter of 500μm, and the bulk density of 1.48g/cm3. The projectile was a ball made of polycarbonate with the diameter of 4.75mm and aluminum, titan, zirconia, stainless steel, cupper, tungsten carbide projectile with the diameter of 2mm. These projectiles were launched at the impact velocity from 0.2 to 7km/s. The target was set in a vacuum chamber evacuated below 10 Pa. We measured the seismic wave by using a piezoelectric uniaxial accelerometer.Result: The impact-induced seismic wave was measured to show a large single peak and found to attenuate with the propagation distance. The maximum acceleration of the seismic wave was recognized to have a good relationship with the normalized distance x/R, where x is the propagation distance

  8. Phase III Randomized Study of Bendamustine Compared With Chlorambucil in Previously Untreated Patients With Chronic Lymphocytic Leukemia

    Wolfgang U. Knauf; Toshko Lissichkov; Ali Aldaoud; Anna Liberati; Javier Loscertales; Raoul Herbrecht; Gunnar Juliusson; Gerhard Postner; Liana Gercheva; Stefan Goranov; Martin Becker; Hans-Joerg Fricke; Francoise Huguet; Ilaria Del Giudice; Peter Klein; Lothar Tremmel; Karlheinz Merkle; Marco Montillo


    This randomized, open-label, parallel-group, multicenter study was designed to compare the efficacy and safety of bendamustine and chlorambucil in previously untreated patients with advanced (Binet stage B or C...

  9. Study of seismicity around Toba area based on relocation hypocenter result from BMKG catalogue

    Ramdhan, Mohamad [Indonesia' s Agency for Meteorology, Climatology and Geophysics (BMKG) Jl. Angkasa 1 No. 2 Kemayoran, Jakarta Pusat, 10720 (Indonesia); Nugraha, Andri Dian [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Indonesia, Jl. Ganesa 10, Bandung, 40132 (Indonesia)


    Toba area has complex tectonic setting attracting many earth scientists to study and understand tectonic and geological process or setting. The area is affected by oblique subduction zone, Renun Sumatran fault sub segment and some volcanoes that are near it. The earthquake catalogue provided by BMKG from April, 2009 to December, 2011 must be relocated firstly to get the precise hypocenter. We used catalogue data of P and S phase or P phase only and double-difference method to relocate the earthquakes. The results show hypocenter position enhancement that can be interpreted tectonically. The earthquakes after relocation relating to the Sumatran fault, subduction zone, volcanoes and seismic activities beneath Toba caldera can be mapped clearly. The relocated hypocenters in this study are very important to provide information for seismic hazard assessment and disaster mitigation study.

  10. Study of seismicity around Toba area based on relocation hypocenter result from BMKG catalogue

    Ramdhan, Mohamad; Nugraha, Andri Dian


    Toba area has complex tectonic setting attracting many earth scientists to study and understand tectonic and geological process or setting. The area is affected by oblique subduction zone, Renun Sumatran fault sub segment and some volcanoes that are near it. The earthquake catalogue provided by BMKG from April, 2009 to December, 2011 must be relocated firstly to get the precise hypocenter. We used catalogue data of P and S phase or P phase only and double-difference method to relocate the earthquakes. The results show hypocenter position enhancement that can be interpreted tectonically. The earthquakes after relocation relating to the Sumatran fault, subduction zone, volcanoes and seismic activities beneath Toba caldera can be mapped clearly. The relocated hypocenters in this study are very important to provide information for seismic hazard assessment and disaster mitigation study.

  11. Study of seismic response and vibration control of High voltage electrical equipment damper based on TMD

    Liu, Chuncheng; Wang, Chongyang; Mao, Long; Zha, Chuanming


    Substation high voltage electrical equipment such as mutual inductor, circuit interrupter, disconnecting switch, etc., has played a key role in maintaining the normal operation of the power system. When the earthquake disaster, the electrical equipment of the porcelain in the transformer substation is the most easily to damage, causing great economic losses. In this paper, using the method of numerical analysis, the establishment of a typical high voltage electrical equipment of three dimensional finite element model, to study the seismic response of a typical SF6 circuit breaker, at the same time, analysis and contrast the installation ring tuned mass damper (TMD damper for short), by changing the damper damping coefficient and the mass block, install annular TMD vibration control effect is studied. The results of the study for guiding the seismic design of high voltage electrical equipment to provide valuable reference.

  12. Effective Teaching and Learning Environments and Principal Self-Efficacy in Oklahoma: Replication of a Previous Study

    Berry, Kathryn


    The purpose of this study was to replicate a previous study by Smith et al. (2006) that explored principal self-efficacy beliefs for facilitating effective instructional environments at their schools. There has been limited research conducted on principal's self-efficacy, and the studies that have been completed on the topic have not been…

  13. Seismic slope stability of embankments: a comparative study on EC8 provisions

    Zania, Varvara; Tsompanakis, Y.; Psarropoulos, P.N.


    their dynamic response and the permanent seismic displacements. After calculating the horizontal and vertical seismic coefficients from parametric dynamic numerical analyses the seismic permanent displacements were estimated according to Newmark’s sliding block approach. Seismic coefficient spectra for circular...... failure surfaces, based on two levels of acceptable seismic displacements, are proposed. For deep failure surfaces, coupled analyses of a SDOF system with sliding potential along its base have been performed and the critical acceleration was established. The results indicate that displacements...

  14. Reflection seismic studies at the Laxemar area; Reflektionsseismiska studier inom Laxemaromraadet

    Bergman, B.; Juhlin, C.; Palm, H. [Uppsala Univ. (Sweden). Dept. of Earth Sciences


    Two 2 km long crossing lines with high-resolution reflection seismics were acquired at Laxemar, close to The Aespoe Hard Rock Laboratory, in December 1999. The main goal with the investigation was to make a full-scale test of developed methods in reflection seismics with the use of small shotholes and small explosive charges. The secondary goal was to identify fracture zones that might correlate with water bearing fracture zones found in boreholes. Both lines had 10-meter separation between the geophones and charge holes. Shot sizes were 15-gram plastic explosives for shots in rock and 75-gram ones for shots in lose sediments and till. The results from the measurements show that the small shotholes technique and small charges works well to investigate the rock down to a depth of 3-4 kilometers. The signal penetrates at least to 1500-metres (500 ms travel time for the seismic signal) along both lines. Over some parts of the lines the seismic signal penetrates to c. 6000- metres (2 seconds travel time). Five dipping reflectors (c. 30-50 deg) can be identified. Three of these can be projected up to the surface on both lines and their 3D orientation can be determined. These reflectors also coincide with topographical depressions. The two other dipping reflectors are only visible on one line, but can be assumed to correlate with topographical depressions and that way be assigned a three dimensional orientation. Four of the reflectors correlate with previously mapped fracture zones. A zone of sub-horizontal reflectivity (0-15 deg) is visible at 650-900 meters depth where the lines cross the deep borehole KLX02. This zone dips gently towards the east and can be correlated with sections of greenstones found in KLX02. The zone of sub-horizontal reflectivity continues to the deep borehole KLX01, but is not as clear here. This sub-horizontal zone may be the hydraulic connection between the boreholes in their deeper part. Deeper down at 1100 ms (c. 3 km), there are strong

  15. Seismic Symphonies

    Strinna, Elisa; Ferrari, Graziano


    The project started in 2008 as a sound installation, a collaboration between an artist, a barrel organ builder and a seismologist. The work differs from other attempts of sound transposition of seismic records. In this case seismic frequencies are not converted automatically into the "sound of the earthquake." However, it has been studied a musical translation system that, based on the organ tonal scale, generates a totally unexpected sequence of sounds which is intended to evoke the emotions aroused by the earthquake. The symphonies proposed in the project have somewhat peculiar origins: they in fact come to life from the translation of graphic tracks into a sound track. The graphic tracks in question are made up by copies of seismograms recorded during some earthquakes that have taken place around the world. Seismograms are translated into music by a sculpture-instrument, half a seismograph and half a barrel organ. The organ plays through holes practiced on paper. Adapting the documents to the instrument score, holes have been drilled on the waves' peaks. The organ covers about three tonal scales, starting from heavy and deep sounds it reaches up to high and jarring notes. The translation of the seismic records is based on a criterion that does match the highest sounds to larger amplitudes with lower ones to minors. Translating the seismogram in the organ score, the larger the amplitude of recorded waves, the more the seismogram covers the full tonal scale played by the barrel organ and the notes arouse an intense emotional response in the listener. Elisa Strinna's Seismic Symphonies installation becomes an unprecedented tool for emotional involvement, through which can be revived the memory of the greatest disasters of over a century of seismic history of the Earth. A bridge between art and science. Seismic Symphonies is also a symbolic inversion: the instrument of the organ is most commonly used in churches, and its sounds are derived from the heavens and

  16. Recent progress of deep seismic experiments and studies of crustal structure in northern South China Sea


    The South China Sea (SCS) is one of the largest marginal seas in the western Pacific. Its northern part has the features of a passive continental margin. The studies of deep crustal structure in this area are very important for understanding the tectonic nature, evolution history, basin formation of the northern margin, and the origin of the SCS. In the past decades, the deep seismic experiments of crustal studies in the northern SCS have gone through three stages, namely the sonobuoy, two-ship Expanding Spread Profile (ESP), and Ocean Bottom Hydrophone/Seismometer (OBH/OBS). Along the continental slope, the sonobuoy experiments provided useful information about the velocity structure of the upper crust, while the ESP data recorded for the first time the seismic signals from deep crustal structure and Moho interface. And the OBH/OBS profiles revealed the crustal structure in much greater detail. This paper first gives a brief historical review of these deep seismic experiments and studies, then a summary of the latest progress and important research results. The remaining problems and suggestions for further research work are presented as conclusive remarks.

  17. Assessing sensitivity of Probabilistic Seismic Hazard Analysis (PSHA) to fault parameters: Sumatra case study

    Omang, A.; Cummins, P. R.; Horspool, N.; Hidayati, S.


    Slip rate data and fault geometry are two important inputs in determining seismic hazard, because they are used to estimate earthquake recurrence intervals which strongly influence the hazard level in an area. However, the uncertainty of slip-rates and geometry of the fault are rarely considered in any probabilistic seismic hazard analysis (PSHA), which is surprising given the estimates of slip-rates can vary significantly from different data sources (e.g. geological vs. Geodetic). We use the PSHA method to assess the sensitivity of seismic hazard to fault slip-rates along the Great Sumatran Fault in Sumatra, Indonesia. We will consider the epistemic uncertainty of fault slip rate by employing logic trees to include alternative slip rate models. The weighting of the logic tree is determined by the probability density function of the slip rate estimates using the approach of Zechar and Frankel (2009). We consider how the PSHA result accounting for slip rate uncertainty differs from that for a specific slip rate by examining hazard values as a function of return period and distance from the fault. We also consider the geometry of the fault, especially the top and the bottom of the rupture area within a fault, to study the effect from different depths. Based on the results of this study, in some cases the uncertainty in fault slip-rates, fault geometry and maximum magnitude have a significant effect on hazard level and area impacted by earthquakes and should be considered in PSHA studies.

  18. Research on seismic stress triggering

    万永革; 吴忠良; 周公威; 黄静; 秦立新


    This paper briefly reviews basic theory of seismic stress triggering. Recent development on seismic stress triggering has been reviewed in the views of seismic static and dynamic stress triggering, application of viscoelastic model in seismic stress triggering, the relation between earthquake triggering and volcanic eruption or explosion, other explanation of earthquake triggering, etc. And some suggestions for further study on seismic stress triggering in near future are given.

  19. Deformation Study of Papandayan Volcano using GPS Survey Method and Its Correlation with Seismic Data Observation

    Dina A. Sarsito


    Full Text Available Papandayan volcano located in the southern part of Garut regency, around 70 km away from Bandung city, West Java. Many methods carried out to monitoring the activities of volcano, both continuously or periodically, one of the monitoring method is periodically GPS survey. Basically those surveys are carried out to understand the pattern and velocity of displacement which occurred in the volcano body, both horizontally and vertically, and also others deformation elements such as; translation, rotation and dilatation. The Mogi modeling was also used to determine the location and volume of the pressure source which caused deformation of volcano body. By comparing seismic activity and the deformation reveal from GPS measurement, before, during and after eruption, it could be understood there is a correlation between the seismicity and its deformation. These studies is hoping that GPS measurement in Papandayan volcano could be one of supported method to determine the volcano activities, at least in Papandayan volcano.

  20. Reservoir-induced seismicity associated with the Itoiz Reservoir, Spain: a case study

    Durá-Gómez, Inmaculada; Talwani, Pradeep


    Reservoir-induced seismicity was observed in 2004 after the impoundment of the Itoiz Reservoir in the central-western Pyrenees, Spain. Subsequent annual filling cycles were accompanied by large epicentral growth in the northern part of the Jaca-Pamplona basin. Based on the evaluation of the available geohydrologic data, we suggest that the seismicity is associated with the diffusion of increased pore pressures along the carbonate megabreccia systems of the Early to Middle Eocene age Hecho Group. Assuming 1-D pore-pressure diffusion from the Itoiz Reservoir, we estimate that excess pore pressures of ~100-500 kPa are adequate to induce M >= 3.0 earthquakes in this geological terrane. The results of this study have potential applicability in regions where reservoirs are built over karst terranes.

  1. Seismic studies at the Mt. Hood Volcano, northern Cascade Range, Oregon

    Green, Susan Molly; Weaver, Craig S.; Iyer, Hariharaiyer Mahadeva


    A sixteen station telemetered seismic network was established in the Mt. Hood, Oregon area to monitor local seismicity and to study crustal and upper mantle structure. The network was in operation 13 months, and recorded 10 local earthquakes, 25 regional events, and 300 teleseisms. A series of construction blasts were recorded and used to define an average upper crustal velocity of 5.4 km/s in the region. All local earthquakes occurred beneath Mt. Hood at shallow depths and roughly define a zone striking north-northwest beneath the mountain. The largest earthquake was a magnitude 3.4 event which had a strike-slip focal mechanism. The other events had magnitudes (ML) less than 2.0. P-wave travel time residuals from teleseismic events show a 0.5 second decrease in travel time from east to west across the Cascade Range. No travel time anomalies are associated directly with Mt. Hood.

  2. Maternal and perinatal outcomes of delivery after a previous Cesarean section in Enugu, Southeast Nigeria: a prospective observational study.

    Ugwu, George O; Iyoke, Chukwuemeka A; Onah, Hyacinth E; Egwuatu, Vincent E; Ezugwu, Frank O


    Obstetricians in developing countries appear generally reluctant to conduct vaginal delivery in women with a previous Cesarean because of lack of adequate facilities for optimal fetomaternal monitoring. To describe delivery outcomes among women with one previous Cesarean section at a tertiary hospital in Southeast Nigeria. This was a prospective observational study to determine maternal and perinatal outcomes of attempted vaginal birth after Cesarean sections (VBAC) following one previous Cesarean section. Analysis was done with SPSS statistical software version 17.0 for Windows using descriptive and inferential statistics at 95% level of confidence. Two thousand six hundred and ten women delivered in the center during the study period, of whom 395 had one previous Cesarean section. A total of 370 women with one previous Cesarean section had nonrecurrent indications, of whom 355 consenting pregnant women with one previous Cesarean section were studied. A majority of the women (320/355, 90.1%) preferred to have vaginal delivery despite the one previous Cesarean section. However, only approximately 54% (190/355) were found suitable for trial of VBAC, out of whom 50% (95/190 had successful VBAC. Ninety-five women (50.0%) had failed attempt at VBAC and were delivered by emergency Cesarean section while 35 women (9.8%) had emergency Cesarean section for other obstetric indications (apart from failed VBAC). There was no case of uterine rupture or neonatal and maternal deaths recorded in any group. Apgar scores of less than 7 in the first minute were significantly more frequent amongst women who had vaginal delivery when compared to those who had elective repeat Cesarean section (P=0.03). Most women who had one previous Cesarean delivery chose to undergo trial of VBAC, although only about half were considered suitable for VBAC. The maternal and fetal outcomes of trial of VBAC in selected women with one previous Cesarean delivery for non-recurrent indications were good

  3. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement

    Wanlin Cao


    Full Text Available Recycled concrete brick (RCB is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied.

  4. Experimental Study on the Seismic Performance of Recycled Concrete Brick Walls Embedded with Vertical Reinforcement

    Cao, Wanlin; Zhang, Yongbo; Dong, Hongying; Zhou, Zhongyi; Qiao, Qiyun


    Recycled concrete brick (RCB) is manufactured by recycled aggregate processed from discarded concrete blocks arising from the demolishing of existing buildings. This paper presents research on the seismic performance of RCB masonry walls to assess the applicability of RCB for use in rural low-rise constructions. The seismic performance of a masonry wall is closely related to the vertical load applied to the wall. Thus, the compressive performance of RCB masonry was investigated firstly by constructing and testing eighteen RCB masonry compressive specimens with different mortar strengths. The load-bearing capacity, deformation and failure characteristic were analyzed, as well. Then, a quasi-static test was carried out to study the seismic behavior of RCB walls by eight RCB masonry walls subjected to an axial compressive load and a reversed cyclic lateral load. Based on the test results, equations for predicting the compressive strength of RCB masonry and the lateral ultimate strength of an RCB masonry wall were proposed. Experimental values were found to be in good agreement with the predicted values. Meanwhile, finite element analysis (FEA) and parametric analysis of the RCB walls were carried out using ABAQUS software. The elastic-plastic deformation characteristics and the lateral load-displacement relations were studied. PMID:28788170

  5. Estimating the effect of current, previous and never use of drugs in studies based on prescription registries

    Nielsen, Lars Hougaard; Løkkegaard, Ellen; Andreasen, Anne Helms;


    PURPOSE: Many studies which investigate the effect of drugs categorize the exposure variable into never, current, and previous use of the study drug. When prescription registries are used to make this categorization, the exposure variable possibly gets misclassified since the registries do not ca...... with Hazard Ratios ranging from 1.68 to 1.78 for current use compared to never use. CONCLUSIONS: The findings suggest that it is possible to estimate the effect of never, current and previous use of HT on breast cancer using prescription data.......PURPOSE: Many studies which investigate the effect of drugs categorize the exposure variable into never, current, and previous use of the study drug. When prescription registries are used to make this categorization, the exposure variable possibly gets misclassified since the registries do...... not carry any information on the time of discontinuation of treatment.In this study, we investigated the amount of misclassification of exposure (never, current, previous use) to hormone therapy (HT) when the exposure variable was based on prescription data. Furthermore, we evaluated the significance...

  6. A microseismic study in a low seismicity area of Italy: the Città di Castello 2000-2001 experiment

    P. Augliera


    Full Text Available Recent seismological studies contribute to better understand the first order characteristics of earthquake occurrence in Italy, identifying the potential sites for moderate to large size earthquakes. Ad hoc passive seismic experiments performed in these areas provide information to focus on the location and geometry of the active faults more closely. This information is relevant for assessing seismic hazard and for accurately constraining possible ground shaking scenarios. The area around the Città di Castello Basin, in the Northern Apennines (Central Italy, is characterized by the absence of instrumental seismicity (M > 2.5, it is adjacent to faults ruptured by recent and historical earthquakes. To better understand the tectonics of the area, we installed a dense network of seismic stations equipped with broadband and short period seismometers collecting data continuously for 8 months (October 2000-May 2001. The processing of ~ 900 Gbyte of data revealed a consistent background seismicity consisting of very low magnitude earthquakes (ML < 3.2. Preliminary locations of about 2200 local earthquakes show that the area can be divided into two regions with different seismic behaviour: an area to the NW, in between Sansepolcro and Città di Castello, where seismicity is not present. An area toward the SE, in between Città di Castello, Umbertide and Gubbio, where we detected a high microseismicity activity. These findings suggest a probable different mechanical behaviour of the two regions. In the latter area, the seismicity is confined between 0 and 8 km of depth revealing a rather well defined east-dipping, low angle fault 35 km wide that cuts through the entire upper crust down to 12-15 km depth. Beside an apparent structural complexity, fault plane solutions of background seismicity reveal a homogeneous pattern of deformation with a clear NE-SW extension.

  7. SA-based concrete seismic stress monitoring: a case study for normal strength concrete

    Hou, S.; Zhang, H. B.; Ou, J. P.


    The stress history of concrete structures that have survived an earthquake can serve as a critical index to evaluate the health of the structure. There are currently few reliable monitoring methods to assess concrete stress after a seismic event. Piezoelectric-based smart aggregate (SA) provides an innovative experimental approach to monitor stress on concrete. The principle of SA-based concrete seismic stress monitoring is based on the assumption that concrete stress can be reliably predicted by the average output voltages of limited SAs with an acceptable margin of error. In this study, the meso-scale randomness of concrete was evaluated throughout the overall stress range of concrete and the influence of different load paths was considered. Four cylindrical specimens of normal strength concrete were embedded with a total of 24 SAs. The SA output sensitivity curve in the paths of loading-unloading with different amplitudes and monotonic loading up to failure was obtained. Monitoring errors were analyzed during pre- and post-peak stages from the experimental results. This research suggests that SA-based concrete seismic stress monitoring for normal strength concrete is reliable.

  8. Coherent features of the Alpine mantle slabs imaged by recent seismic tomography studies

    Brueckl, E.; Brueckl, J.; Keller, G. R.; Dando, B.


    The bifurcation of the East Alpine mountain range into branches extending northeastward to the Carpathians and southeastward to the Dinarides represents a triple junction between the European platform (EU), the Adriatic micro-plate (AD), and the Pannonian fragment (PA). During the last decade, controlled source and passive source seismic data have provided a variety of detailed images of the lithosphere and upper mantle in this area. However, the geodynamic interpretation of lithospheric slabs under the Alpine - Adriatic collision zone is still under debate. So far, arguments have been based mainly on images provided by individual seismic tomography studies. In order to enhance robust features of the upper mantle structure, we have averaged four tomographic models, weighted according to their coverage by seismic stations and boundaries of high resolution. We achieved an image of the Alpine slab of unprecedented clarity. It extends coherently from the border between the Western Alps and the Apennines to the EU-AD-PA triple junction, dipping southeastward in the west and nearly vertically in the east. The whole slab can be connected to European mantle lithosphere and a flip of subduction polarity must not be induced. The geometry of the slab infers also additional constraints on the development of the triple junction during the post-collision phase of the Eastern Alps.

  9. Deep seismic reflection study over the Vindhyans of Rajasthan: Implications for geophysical setting of the basin

    B Rajendra Prasad; V Vijaya Rao


    This paper presents results of high-resolution deep seismic reflection profiling of the Proterozoic Vindhyan basin of the Rajasthan area along the Chandli –Bundi –Kota –Kunjer pro file.Seismic images have been used to estimate the thickness of Vindhyan strata as well as to understand the tectonic framework of the basin.The results are constrained by gravity,magnetic and magne-totelluric data.The study reveals gentle SE-dipping reflection bands representing the Vindhyan strata.The seismic sections depict gradual thickening of the Vindhyan succession towards south-east from Bundi.The velocities of the upper and lower Vindhyans are identified as 4.6 –4.8 km/s and 5.1 –5.3 km/s.The NW limit of the Vindhyan basin is demarcated by the Great Boundary Fault (GBF)that manifests as a 30 km wide NW dipping thrust fault extending to a depth of 30 km.

  10. Seismic Earth Pressure Development in Sheet Pile Retaining Walls: A Numerical Study

    Rajeev, P; Sivakugan, N


    The design of retaining walls requires the complete knowledge of the earth pressure distribution behind the wall. Due to the complex soil-structure effect, the estimation of earth pressure is not an easy task; even in the static case. The problem becomes even more complex for the dynamic (i.e., seismic) analysis and design of retaining walls. Several earth pressure models have been developed over the years to integrate the dynamic earth pressure with the static earth pressure and to improve the design of retaining wall in seismic regions. Among all the models, MononobeOkabe (M-O) method is commonly used to estimate the magnitude of seismic earth pressures in retaining walls and is adopted in design practices around the world (e.g., EuroCode and Australian Standards). However, the M-O method has several drawbacks and does not provide reliable estimate of the earth pressure in many instances. This study investigates the accuracy of the M-O method to predict the dynamic earth pressure in sheet pile wall. A 2D pl...

  11. Principle and Program of Evaluating Diffuse Seismicity

    Chang Xiangdong


    Concept and origin of the term "the diffuse seismicity" are illustrated. Some different viewpoints regarding the diffuse seismicity and the influence characteristics on determining seismic design basis of engineering from the seismicity are analyzed. Principle and program for evaluating diffuse seismicity are studied and discussed base on over contents.

  12. A detailed study of the Pernik (Bulgaria) seismic sequence of 2012

    Raykova, Plamena; Solakov, Dimcho; Simeonova, Stela; Dimitrova, Liliya


    A detailed study of the Pernik (Bulgaria) seismic sequence of 2012 D.Solakov, S.Simeonova ,I. Georgiev, P.Raykova, L.Dimitrova and V.Protopopova National Institute of Geophysics, Geodesy and Geography-BAS, Sofia, Bulgaria The spatial and temporal clustering of aftershocks is the dominant non-random element of seismicity, so that when aftershocks are removed, the remaining activity can be modelled (as first approximation) as a Poisson process. The properties of aftershock sequences (distinct cluster, for example; even aftershocks can have aftershocks) allow time-dependent prediction of aftershock probabilities. Consideration of recent earthquake sequences suggests that aftershocks to large earthquakes although they are still, by definition, smaller events, can be very damaging and should be addressed in emergence planning scenarios. Because of the factors such as location and radiation pattern and the cumulative nature of building damage, aftershocks can cause more damage than the main shock. An earthquake of moment magnitude 5.6 hit Sofia seismic zone, on May 22nd, 2012. The earthquake occurred in the vicinity of Pernik city, at about 25 km south west of the city of Sofia (the capital of Bulgaria). The event was followed by intensive activity. The active area is situated in the central part of western Bulgaria. That is the most populated (more than 1.2 mil. inhabitants), industrial and cultural region of Bulgaria. Seismicity in the zone is related to the marginal neotectonic faults of Sofia graben. The boundaries of the graben are represented by SE-NW fault system with expressive neotectonic activity. This zone is characterized by shallow earthquakes. The strongest known event in the region is the 1858 quake with intensity I0=9-10 MSK. The 1858 earthquake caused heavy destruction in the city of Sofia and the appearance of thermal spring. It is worth mentioning that the seismic sequence of May 2912 occurred in an area characterized by a long quiescence (of 95 years

  13. Probabilistic seismic safety assessment of a CANDU 6 nuclear power plant including ambient vibration tests: Case study

    Nour, Ali [Hydro Québec, Montréal, Québec H2L4P5 (Canada); École Polytechnique de Montréal, Montréal, Québec H3C3A7 (Canada); Cherfaoui, Abdelhalim; Gocevski, Vladimir [Hydro Québec, Montréal, Québec H2L4P5 (Canada); Léger, Pierre [École Polytechnique de Montréal, Montréal, Québec H3C3A7 (Canada)


    Highlights: • In this case study, the seismic PSA methodology adopted for a CANDU 6 is presented. • Ambient vibrations testing to calibrate a 3D FEM and to reduce uncertainties is performed. • Procedure for the development of FRS for the RB considering wave incoherency effect is proposed. • Seismic fragility analysis for the RB is presented. - Abstract: Following the 2011 Fukushima Daiichi nuclear accident in Japan there is a worldwide interest in reducing uncertainties in seismic safety assessment of existing nuclear power plant (NPP). Within the scope of a Canadian refurbishment project of a CANDU 6 (NPP) put in service in 1983, structures and equipment must sustain a new seismic demand characterised by the uniform hazard spectrum (UHS) obtained from a site specific study defined for a return period of 1/10,000 years. This UHS exhibits larger spectral ordinates in the high-frequency range than those used in design. To reduce modeling uncertainties as part of a seismic probabilistic safety assessment (PSA), Hydro-Québec developed a procedure using ambient vibrations testing to calibrate a detailed 3D finite element model (FEM) of the containment and reactor building (RB). This calibrated FE model is then used for generating floor response spectra (FRS) based on ground motion time histories compatible with the UHS. Seismic fragility analyses of the reactor building (RB) and structural components are also performed in the context of a case study. Because the RB is founded on a large circular raft, it is possible to consider the effect of the seismic wave incoherency to filter out the high-frequency content, mainly above 10 Hz, using the incoherency transfer function (ITF) method. This allows reducing significantly the non-necessary conservatism in resulting FRS, an important issue for an existing NPP. The proposed case study, and related methodology using ambient vibration testing, is particularly useful to engineers involved in seismic re-evaluation of

  14. An fMRI study of neuronal activation in schizophrenia patients with and without previous cannabis use

    Else-Marie eLøberg


    Full Text Available Previous studies have mostly shown positive effects of cannabis use on cognition in patients with schizophrenia, which could reflect lower neurocognitive vulnerability. There are however no studies comparing whether such cognitive differences have neuronal correlates. Thus, the aim of the present study was to compare whether patients with previous cannabis use differ in brain activation from patients who has never used cannabis. The patients groups were compared on the ability to up-regulate an effort mode network during a cognitive task and down-regulate activation in the same network during a task-absent condition. Task-present and task-absent brain activation was measured by functional magnetic resonance neuroimaging (fMRI. Twenty-six patients with a DSM-IV and ICD-10 diagnosis of schizophrenia were grouped into a previous cannabis user group and a no-cannabis group. An auditory dichotic listening task with instructions of attention focus on either the right or left ear stimulus was used to tap verbal processing, attention and cognitive control, calculated as an aggregate score. When comparing the two groups, there were remaining activations in the task-present condition for the cannabis group, not seen in the no-cannabis group, while there was remaining activation in the task-absent condition for the no-cannabis group, not seen in the cannabis group. Thus, the patients with previous cannabis use showed increased activation in an effort mode network and decreased activation in the default mode network as compared to the no-cannabis group. It is concluded that the present study show some differences in brain activation to a cognitively challenging task between previous cannabis and no-cannabis schizophrenia patients.

  15. Angola Seismicity MAP

    Neto, F. A. P.; Franca, G.


    The purpose of this job was to study and document the Angola natural seismicity, establishment of the first database seismic data to facilitate consultation and search for information on seismic activity in the country. The study was conducted based on query reports produced by National Institute of Meteorology and Geophysics (INAMET) 1968 to 2014 with emphasis to the work presented by Moreira (1968), that defined six seismogenic zones from macro seismic data, with highlighting is Zone of Sá da Bandeira (Lubango)-Chibemba-Oncócua-Iona. This is the most important of Angola seismic zone, covering the epicentral Quihita and Iona regions, geologically characterized by transcontinental structure tectono-magmatic activation of the Mesozoic with the installation of a wide variety of intrusive rocks of ultrabasic-alkaline composition, basic and alkaline, kimberlites and carbonatites, strongly marked by intense tectonism, presenting with several faults and fractures (locally called corredor de Lucapa). The earthquake of May 9, 1948 reached intensity VI on the Mercalli-Sieberg scale (MCS) in the locality of Quihita, and seismic active of Iona January 15, 1964, the main shock hit the grade VI-VII. Although not having significant seismicity rate can not be neglected, the other five zone are: Cassongue-Ganda-Massano de Amorim; Lola-Quilengues-Caluquembe; Gago Coutinho-zone; Cuima-Cachingues-Cambândua; The Upper Zambezi zone. We also analyzed technical reports on the seismicity of the middle Kwanza produced by Hidroproekt (GAMEK) region as well as international seismic bulletins of the International Seismological Centre (ISC), United States Geological Survey (USGS), and these data served for instrumental location of the epicenters. All compiled information made possible the creation of the First datbase of seismic data for Angola, preparing the map of seismicity with the reconfirmation of the main seismic zones defined by Moreira (1968) and the identification of a new seismic

  16. JPEG image of Seismic-Reflection Profiles Collected in the Pulley Ridge Study Area

    U.S. Geological Survey, Department of the Interior — These seismic data were collected to infer the paleodepositional environment of Pulley Ridge through seismic facies analysis. Without actual rock cores, remote...

  17. JPEG image of Seismic-Reflection Profiles Collected in the Pulley Ridge Study Area

    U.S. Geological Survey, Department of the Interior — These seismic data were collected to infer the paleodepositional environment of Pulley Ridge through seismic facies analysis. Without actual rock cores, remote...

  18. Comparison between seismic and domestic risk in moderate seismic hazard prone region: the Grenoble City (France test site

    F. Dunand


    Full Text Available France has a moderate level of seismic activity, characterized by diffuse seismicity, sometimes experiencing earthquakes of a magnitude of more than 5 in the most active zones. In this seismicity context, Grenoble is a city of major economic and social importance. However, earthquakes being rare, public authorities and the decision makers are only vaguely committed to reducing seismic risk: return periods are long and local policy makers do not have much information available. Over the past 25 yr, a large number of studies have been conducted to improve our knowledge of seismic hazard in this region. One of the decision-making concerns of Grenoble's public authorities, as managers of a large number of public buildings, is to know not only the seismic-prone regions, the variability of seismic hazard due to site effects and the city's overall vulnerability, but also the level of seismic risk and exposure for the entire city, also compared to other natural or/and domestic hazards. Our seismic risk analysis uses a probabilistic approach for regional and local hazards and the vulnerability assessment of buildings. Its applicability to Grenoble offers the advantage of being based on knowledge acquired by previous projects conducted over the years. This paper aims to compare the level of seismic risk with that of other risks and to introduce the notion of risk acceptability in order to offer guidance in the management of seismic risk. This notion of acceptability, which is now part of seismic risk consideration for existing buildings in Switzerland, is relevant in moderately seismic-prone countries like France.

  19. Experimental Study on Seismic Performance of Tall Building with Steel Transfer Trusses Located at a Higher Level

    LIU Jing-song; QIU Tao


    Based on a shaking table experiment of 1 : 25 scale frame-shearwall structure model with steel transfer trusses, the dynamic characteristics, seismic responses in elastic and elastic-plastic phases with de- structive forms of the structure were studied. It was observed that cracks were developed with earthquake wave acceleration increasing, but no severe crack was developed in the structure during the experiment. In the seismic responses caused by artificial wave, site wave and E1 Centro wave, that caused by the artificial wave is the most intense one. Displacement angle between steel transfer trusses is large, which means the transfer stories might be weak. However, the seismic performance of the steel transfer trusses is good and the overall structure can satisfy seismic fortification requirements in the region of intensity 6.

  20. Estimation of seismically detectable portion of a gas plume: CO2CRC Otway project case study

    Pevzner, Roman; Caspari, Eva; Bona, Andrej; Galvin, Robert; Gurevich, Boris


    CO2CRC Otway project comprises of several experiments involving CO2/CH4 or pure CO2 gas injection into different geological formations at the Otway test site (Victoria, Australia). During the first stage of the project, which was finished in 2010, more than 64,000 t of gas were injected into the depleted gas reservoir at ~2 km depth. At the moment, preparations for the next stage of the project aiming to examine capabilities of seismic monitoring of small scale injection (up to 15,000 t) into saline formation are ongoing. Time-lapse seismic is one of the most typical methods for CO2 geosequestration monitoring. Significant experience was gained during the first stage of the project through acquisition and analysis of the 4D surface seismic and numerous time-lapse VSP surveys. In order to justify the second stage of the project and optimise parameters of the experiment, several modelling studies were conducted. In order to predict seismic signal we populate realistic geological model with elastic properties, model their changes using fluid substitution technique applied to the fluid flow simulation results and compute synthetic seismic baseline and monitor volumes. To assess detectability of the time-lapse signal caused by the injection, we assume that the time-lapse noise level will be equivalent to the level of difference between the last two Otway 3D surveys acquired in 2009 and 2010 using conventional surface technique (15,000 lbs vibroseis sources and single geophones as the receivers). In order to quantify the uncertainties in plume imaging/visualisation due to the time-lapse noise realisation we propose to use multiple noise realisations with the same F-Kx-Ky amplitude spectra as the field noise for each synthetic signal volume. Having signal detection criterion defined in the terms of signal/time- lapse noise level on a single trace we estimate visible portion of the plume as a function of this criterion. This approach also gives an opportunity to attempt to

  1. Lithospheric studies along seismic profile KOKKY, between Gulf of Bothnia and Gulf of Finland, Baltic Shield

    Tiira, Timo; Skrzynik, Tymon; Janik, Tomasz; Komminaho, Kari; Väkevä, Sakari; Korja, Annakaisa


    Controlled source seismology is one of the main tools used in Earth imaging, especially when aiming towards the middle and lower crust structures, Moho shape and upper mantle. Data for such studies are acquired during wide-angle reflection and refraction (WARR) profiles, which are hundreds of kilometers long and require strong explosive sources like e.g. TNT. Given the cost of such experiments, difficult logistics, and the strict regulation on experiments involving explosives in the ground, an attempt was made to register quarry blasts along the set profile. Quarries consume tons of explosive material per week and their utility in crustal studies was already tested during HUKKA experiment in 2007. Profile KOKKY begins on the coast of Bothnian Bay and runs south-east towards Sankt Petersburg in Russia. It crosses three main geological units of southern Finland, Pohjanmaa area, Central Finland Granitoid Complex, and Saimaa area, all represented by Late Proterozoic rocks. Two summer acquisition campaigns resulted in nearly 500 km long profile, crossing southern Finland. Numerous explosions from quarries were recorded, resulting in 63 usable seismic sections. Average distance between shots and the profile was 14 km. The velocity model has high P wave velocities across the entire profile. Upper crust, reaching depths of 22 km, is characterized by velocities from 5.9-6.2 km/s near surface down to 6.25-6.4 km/s. Middle crust is thinning from 30 km at NW, down to 14 km in the central part of the profile, thickening again to 20 km at SE, and has uniformed velocities 6.6-6.8 km/s. High, homogeneous velocities in lower crust, up to 7.4 km/s. Layer is thickening from 4 km in SE part of the profile, reaching 18 km in its central part corresponding to CFGC, and then thinning again to about 12 km in NW part. Moho depth varies from 54 km near the Gulf of Bothnia to 63 km in the middle of the profile, and up to 43 km in Saimaa area. Velocities below the crust are 8.2-8.25 km

  2. A Feasibility Study of an FEM Simulation Used in Co-Seismic Deformations: A Case Study of a Dip-Slip Fault

    Xiaoguang Lin


    Full Text Available For this study, we conducted a numerical simulation on co-seismic displacement for a dip-slip fault in a half-space medium based upon a finite element method (FEM. After investigating technical problems of modeling, source and boundary treatment, we calculated co-seismic deformation with consideration to topography. To verify the numerical simulation results, the simulated co-seismic displacement was compared with that calculated using a dislocation theory. As a case study, considering the seismic parameters of the 2008 Wenchuan earthquake (M 8.0 as a source model, we calculate the co-seismic displacements with or without consideration of the terrain model in the finite element model to observe terrain effects on co-seismic deformation. Results show that topography has a non-negligible effect on co-seismic displacement, reaching from -11.59 to 4.0 cm in horizontal displacement, and from -3.28 to 3.28 cm in vertical displacement. The relative effects are 9.05 and 2.95% for horizontal and vertical displacement, respectively. Such a terrain effect is sufficiently large and can be detected by modern geodetic measurements such as GPS. Therefore, we conclude that the topography should be considered in applying dislocation theory to calculate co-seismic deformations.

  3. 3D Seismic Attributes for Structural Analysis in Compressional Context:A Case Study from Western Sichuan Basin

    Bo Xu; Ancheng Xiao; Lei Wu; Liguang Mao; Youpu Dong; Lijun Zhou


    Compressional region usually forms complex thrust faults system, which is difficult to identify using traditional migration profiles. The successful application of three-dimensional (3D) seismic attributes analysis greatly reduces the difficulty, and improves the accuracy and efficiency of seismic interpretation and structural analysis. In this paper, we took Qiongxi area in the compression-al region of western Sichuan as an example, using two 3D seismic attributes, coherence and instanta-neous phase, to identify fault assemblages and variations both vertically and laterally. The results show that the study area mainly consists of NS-, NE- and NEE-trending faults. The NS-trending faults are the largest and have a component of sinistral slip controlling the formation of NEE-trending faults, while the NE-trending faults are intermediate in scale, formed earlier and were cut by the NS-trending faults. Our results demonstrate that using seismic attributes for structural analysis have the following advantages: (1) more details of major fault zones, (2) highlighting minor faults which are hardly traced in seismic migration cube, and (3) easier acquisition of accurate fault systems. The application of seismic attributes provides a new idea for deciphering fine and complicated structures, and will sig-nificantly contribute to the development of objective and precise geological interpretation in the fu-ture.

  4. Factors Associated with Unfavorable Treatment Outcomes in New and Previously Treated TB Patients in Uzbekistan: A Five Year Countrywide Study.

    Jamshid Gadoev

    Full Text Available TB is one of the main health priorities in Uzbekistan and relatively high rates of unfavorable treatment outcomes have recently been reported. This requires closer analysis to explain the reasons and recommend interventions to improve the situation. Thus, by using countrywide data this study sought to determine trends in unfavorable outcomes (lost-to-follow-ups, deaths and treatment failures and describe their associations with socio-demographic and clinical factors.A countrywide retrospective cohort study of all new and previously treated TB patients registered in the National Tuberculosis programme between January 2006 and December 2010.Among 107,380 registered patients, 67% were adults, with smaller proportions of children (10%, adolescents (4% and elderly patients (19%. Sixty per cent were male, 66% lived in rural areas, 1% were HIV-infected and 1% had a history of imprisonment. Pulmonary TB (PTB was present in 77%, of which 43% were smear-positive and 53% were smear-negative. Overall, 83% of patients were successfully treated, 6% died, 6% were lost-to-follow-up, 3% failed treatment and 2% transferred out. Factors associated with death included being above 55 years of age, HIV-positive, sputum smear positive, previously treated, jobless and living in certain provinces. Factors associated with lost-to-follow-up were being male, previously treated, jobless, living in an urban area, and living in certain provinces. Having smear-positive PTB, being an adolescent, being urban population, being HIV-negative, previously treated, jobless and residing in particular provinces were associated with treatment failure.Overall, 83% treatment success rate was achieved. However, our study findings highlight the need to improve TB services for certain vulnerable groups and in specific areas of the country. They also emphasize the need to develop unified monitoring and evaluation tools for drug-susceptible and drug-resistant TB, and call for better TB

  5. Interrelation among several important links in seismic risk analysis

    HUANG Wei-qiong; WU Xuan


    In order to further reveal the interrelation among division of seismic statistical regions, delimitation of potential seismic sources and estimation of seismicity parameters, we select 21 representative sites located in different places within the range of 100°~120°E, 29°~42°N to study the influences of seismicity parameter uncertainties of statistical regions on seismic risk estimations of these sites in the inhomogeneous and homogeneous distribution models. Combining the results from this study and previous ones, we can see that different schemes for dividing seismic statistical regions can change the seismic data in a statistical region. The uncertain data and additional uncertainty in selecting time intervals for seismic statistics will result in uncertainty of seismicity parameters estimation in a statistical region. For the homogeneous model, the larger the variation of this uncertainty is, the greater the uncertain influence on the seismic risk estimation of a site will be, which means that the division of seismic statistical regions makes a major contribution. In a seismic statistical region, the delimitation of potential sources and variant weight assignment of spatial distribution functions can raise the estimated values of ground motion parameters in the place where great earthquake might occur and its vicinity. In these places, the influence of uncertainty in potential source delimitation is very obvious, especially on the absolute magnitude of ground motion parameters (e.g., intensity), which means that the link of potential source delimitation makes a major effect. Generally speaking, the link of potential source delimitation affects mainly the sites located in the potential sources with the highest and second-high upper-limit earthquake magnitudes or in the vicinity of those with the highest upper-limit magnitude. While for the sites located in the potential sources with low upper-limit magnitudes, the uncertainty influence of statistical

  6. Assessment of empathy in first-episode psychosis and meta-analytic comparison with previous studies in schizophrenia.

    Achim, Amelie M; Ouellet, Rosalie; Roy, Marc-André; Jackson, Philip L


    Empathy is a multidimensional construct that relies on affective and cognitive component processes. A few studies have reported impairments of both cognitive and affective empathy components in patients with schizophrenia. It is, however, not known whether these difficulties are already present at psychosis onset. The affective and cognitive components of empathy were thus assessed in 31 patients with first-episode psychosis (FEP) and 31 matched healthy controls using the Interpersonal Reactivity Index (IRI). Our results were then compared to previous studies of empathy in patients with more chronic schizophrenia via a meta-analysis. In addition, we also assessed the relationship between empathy ratings, Mentalizing performance and clinical symptoms. Contrary to what has been reported in people with more chronic schizophrenia, the IRI ratings did not significantly differ between FEP and controls in our study, though a trend was observed for the Personal distress scale. For the Perspective taking scale, our meta-analysis revealed a significantly lower effect size in this study with FEP patients relative to previous schizophrenia studies. In the FEP group, the IRI ratings were not related to positive, negative or general psychopathology symptoms, but a significant relationship emerged between the Liebowitz Social Anxiety Scale and Perspective taking (negative correlation). In addition, a significant positive correlation was observed between the Empathic concern subscale and our theory of mind task. This study supports the idea that the cognitive component of empathy is less affected in patients with first-episode psychosis relative to patients with more chronic schizophrenia, and the impairments reported in previous reports with more chronic populations should be interpreted in light of a possible deterioration of this cognitive skill. The findings also provide some insight into the relationship between empathy and clinical symptoms such as social anxiety.

  7. Experimental Study on Seismic Behavior ofSeismic-damaged Lateral Joints in CompositeFrame Consisting of CFSST Columns and SteelBeams Strengthened with Enclosed ReinforcedConcrete


    A new composite strengthening method of seismic-damaged lateral joints in composite frame consisting of Concrete-Filled SquareSteel Tubes (CFSST) columns and steel beams strengthened with enclosed Reinforced Concrete (RC) at the ends of columns andwelding steel plates at the ends of beams was presented. Based on the current design specifications, one half scaled models of 4lateral joints in composite frame consisting of CFSST columns and steel beams were designed and manufactured. One model wasoriginal control specimen, one was strengthened by enclosed RC, and the others were strengthened after pre-damage. The destructiontests under lateral cyclic load on the models were carried. The effectiveness of seismic-damaged joints strengthened with enclosedRC and the reinforcement effect on different levels of seismic damage were studied. The test results show that seismic- damagedjoints in composite frame consisting of CFSST columns and steel beams strengthened with enclosed RC meets the strongcolumn-weak beam joints requirement of seismic design, and the failure modes are of all joints are the bending failure of steel beam.The reinforcement with enclosed RC has a significant on increasing the ultimate capacity and the seismic behaviors of joints. Thestudy indicated the rehabilitated joints recover the level of their original seismic performances before seismic damage in a certainextent damage level. Based on the test data, namely the ultimate capacity, limit displacement, ductility, the energy consumptioncoefficient, limit displacementthe strengthening method of seismic-damaged joints by strengthened with enclosed RC is an effectivemethod for seismic strengthening.

  8. Study of seismicity in the NW Himalaya and adjoining regions using IMS network

    Ali, Sherif M.; Shanker, D.


    The Reviewed Event Bulletin (REB) of the International Data Center (IDC) has been used in order to investigate the seismicity of the Northwest Himalaya and its neighboring region for the time period June 1999 to March 2015 within the geographical coordinates 25-40° N latitude and 65-85° E longitude. We have used a very precisely located earthquake dataset recorded by the International Monitoring System (IMS) Network containing 7,583 events with body wave magnitudes from 2.5 to 6.3. The study area has been subdivided into six regions based on the Flinn-Engdahl (F-E) seismic and geographical regionalization scheme, which was used as the region classifications of the International Data Center catalog. The examined region includes NW India, Pakistan, Nepal, Xizang, Kashmir, and Hindukush. For each region, Magnitudes of completeness (Mc) and Gutenberg-Richter (GR) recurrence parameters ( a and b values) have been estimated. The Gutenberg-Richter analysis is preceded by an overview of the seismotectonics of the study area. The obtained Mc values vary from 3.5 to 3.9. The lower value of Mc was found mainly in Xizang region whereas the higher Mc threshold is evident in Pakistan region. However, the b values vary from 1.19 to 1.48. The lowest b value is recorded in Xizang region, which is mostly related to the Main Karakoram Thrust (MKT) fault, whereas the highest b values are recorded in NW India and Kashmir regions, which are mostly related to the Main Frontal Thrust (MFT) fault. The REB for the selected period has been compared to the most renowned bulletin of global seismicity, namely that issued by the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS). A study of 4,821 events recorded by USGS in the study region indicates that about 36 % of seismic events were missed and the catalog is considered as complete for events with magnitudes ≥4.0. However, both a and b values are obviously higher than those of IMS catalog. The a

  9. Seismic anisotropy in tomographic studies of the upper mantle beneath Southern Europe

    J. Plomerovà


    Full Text Available Regional seismic tomography of Iberia, Italy, the South Balkans and the Aegean region down to about 400 km are discussed along with results of studies on the anisotropic structure of the lithosphere based on an analysis of spatial variations of P-residuals. The P-residual spheres, showing azimuth-incidence angle dependent terms of relative residuals, map lateral changes of the anisotropic structure of the subcrustal lithosphere related to large tectonic units. Isotropic velocity perturbation models correlate, in general, with models of the lithosphere thickness but in some provinces they are affected by neglecting the anisotropic propagation within the lithosphere.

  10. Study of seismicity in the NW Himalaya and adjoining regions using IMS network

    Ali, Sherif M.; Shanker, D.


    The Reviewed Event Bulletin (REB) of the International Data Center (IDC) has been used in order to investigate the seismicity of the Northwest Himalaya and its neighboring region for the time period June 1999 to March 2015 within the geographical coordinates 25-40° N latitude and 65-85° E longitude. We have used a very precisely located earthquake dataset recorded by the International Monitoring System (IMS) Network containing 7,583 events with body wave magnitudes from 2.5 to 6.3. The study area has been subdivided into six regions based on the Flinn-Engdahl (F-E) seismic and geographical regionalization scheme, which was used as the region classifications of the International Data Center catalog. The examined region includes NW India, Pakistan, Nepal, Xizang, Kashmir, and Hindukush. For each region, Magnitudes of completeness (Mc) and Gutenberg-Richter (GR) recurrence parameters (a and b values) have been estimated. The Gutenberg-Richter analysis is preceded by an overview of the seismotectonics of the study area. The obtained Mc values vary from 3.5 to 3.9. The lower value of Mc was found mainly in Xizang region whereas the higher Mc threshold is evident in Pakistan region. However, the b values vary from 1.19 to 1.48. The lowest b value is recorded in Xizang region, which is mostly related to the Main Karakoram Thrust (MKT) fault, whereas the highest b values are recorded in NW India and Kashmir regions, which are mostly related to the Main Frontal Thrust (MFT) fault. The REB for the selected period has been compared to the most renowned bulletin of global seismicity, namely that issued by the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS). A study of 4,821 events recorded by USGS in the study region indicates that about 36 % of seismic events were missed and the catalog is considered as complete for events with magnitudes ≥4.0. However, both a and b values are obviously higher than those of IMS catalog. The a

  11. Double-Difference Tomography in the West Bohemia Seismic Zone: A Study of the 2011 Earthquake Swarm

    Löberich, Eric; Alexandrakis, Catherine; Calo, Marco; Vavryčuk, Václav; Buske, Stefan


    Fluid migration, gas springs and particularly earthquake swarms are indications of ongoing geodynamic processes in the Bohemian Massif. This tectonically active region can be subdivided into several microplates, such as the Moldanubian and Saxothuringian and the block of the Teplá-Barrandian, which formed a complex sutured crust during the Variscian collision. Beyond this subdivision, the geological situation of the Bohemian Massif is further defined by the Eger Rift, the Cheb basin and the Smrčiny pluton. Moreover a thinned crust and lithosphere is typical for the region, whereby the seismic activity is controlled by the Mariánske Láznĕ Fault and the Počatky-Plesná Shear Zone. Former investigations have shown a relationship between the activated fault and the occurrence of swarm earthquakes. In this study, the analysis of the 2011 earthquake swarm was in the focus of the consideration, following previous findings from the 2008 earthquake swarm. Here, the aim is to improve the understanding between the mantle fluids and the generation of earthquake swarms in the West Bohemia Seismic Zone. Thereby double-difference tomography (tomoDD) was applied to the 2011 earthquake swarm data, leading to an enhanced location accuracy of the hypocenters and a sharper image of the fault system, which can be further controlled by hypoDD relocations. The rupture time series and clustering are also investigated. Additionally, a 3D velocity model for the P- and S-wave are derived and evaluated by considering the results of synthetic tests. The P- to S- wave velocity ratio, which is sensitive to the presence of fluids, is calculated directly from the P- and S-wave model and interpreted in relation to the potential presence of mantle fluids. In summary, this study combines the past knowledge about the fault systems and swarms, with the newly calculated velocity model, source migration pattern and cluster analysis. Moreover the earthquake characteristics are investigated in

  12. A case study of waste fluid injection and induced seismicity in the Raton Basin, Trinidad, CO, USA

    Weingarten, M. B.; Ge, S.


    Waste fluid injection into rock formations has been speculated to cause seismicity. This study analyzed the link between the injection of fluid waste from coal-bed methane production and recent earthquakes swarms around the town of Trinidad, Colorado, USA. The study area is in a relatively quiescent intraplate zone, located in the Mesozoic sedimentary formations of the Raton Basin. Since 1999, when waste fluid injection began in the vicinity of Trinidad, more than 175 earthquakes of greater than M2.5 have occurred, representing a more than 30-fold increase in the number of earthquakes as compared with the previous 3 decades. The vast majority of earthquake epicenters are located within 5 km of one of the 24 injection wells. Two years after waste fluid injection began, an earthquake swarm occurred on a NE-trending fault structure, but a causal relationship between the fluid injection and swarm could not be definitively made. Earthquakes and injection continued and, in 2011, another earthquake swarm occurred, possibly reactivating the same NE-trending fault structure. Due to the lack of robust spatial seismometer coverage, earthquake hypocentral depths often have significant uncertainties, but could be at depths co-located with injection depths. The link between fluid waste injection and seismicity is characterized by spatial and temporal correlations as well as pore pressure changes sufficient to induce seismicity at depth. Pore pressure calculations were performed using a two-dimensional analytical solution for a homogeneous and isotropic aquifer with a hydraulic conductivity of 1.0x10^-7 m/s and storage coefficient of 5.0x10^-5. Reservoir model parameters are representative of the Dakota Sandstone, a fluvial and conglomeratic sandstone sequence, which is the dominant formation for injection. Computed pressure buildup in the aquifer was correlated spatially and temporally to earthquake epicenters. Preliminary results suggest that pore pressure changes in the

  13. USGS National Seismic Hazard Maps

    Frankel, A.D.; Mueller, C.S.; Barnhard, T.P.; Leyendecker, E.V.; Wesson, R.L.; Harmsen, S.C.; Klein, F.W.; Perkins, D.M.; Dickman, N.C.; Hanson, S.L.; Hopper, M.G.


    The U.S. Geological Survey (USGS) recently completed new probabilistic seismic hazard maps for the United States, including Alaska and Hawaii. These hazard maps form the basis of the probabilistic component of the design maps used in the 1997 edition of the NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, prepared by the Building Seismic Safety Council arid published by FEMA. The hazard maps depict peak horizontal ground acceleration and spectral response at 0.2, 0.3, and 1.0 sec periods, with 10%, 5%, and 2% probabilities of exceedance in 50 years, corresponding to return times of about 500, 1000, and 2500 years, respectively. In this paper we outline the methodology used to construct the hazard maps. There are three basic components to the maps. First, we use spatially smoothed historic seismicity as one portion of the hazard calculation. In this model, we apply the general observation that moderate and large earthquakes tend to occur near areas of previous small or moderate events, with some notable exceptions. Second, we consider large background source zones based on broad geologic criteria to quantify hazard in areas with little or no historic seismicity, but with the potential for generating large events. Third, we include the hazard from specific fault sources. We use about 450 faults in the western United States (WUS) and derive recurrence times from either geologic slip rates or the dating of pre-historic earthquakes from trenching of faults or other paleoseismic methods. Recurrence estimates for large earthquakes in New Madrid and Charleston, South Carolina, were taken from recent paleoliquefaction studies. We used logic trees to incorporate different seismicity models, fault recurrence models, Cascadia great earthquake scenarios, and ground-motion attenuation relations. We present disaggregation plots showing the contribution to hazard at four cities from potential earthquakes with various magnitudes and

  14. Psychotic illness in first-time mothers with no previous psychiatric hospitalizations: a population-based study.

    Unnur Valdimarsdóttir


    Full Text Available BACKGROUND: Psychotic illness following childbirth is a relatively rare but severe condition with unexplained etiology. The aim of this study was to investigate the impact of maternal background characteristics and obstetric factors on the risk of postpartum psychosis, specifically among mothers with no previous psychiatric hospitalizations. METHODS AND FINDINGS: We investigated incidence rates and potential maternal and obstetric risk factors of psychoses after childbirth in a national cohort of women who were first-time mothers from 1983 through 2000 (n = 745,596. Proportional hazard regression models were used to estimate relative risks of psychoses during and after the first 90 d postpartum, among mothers without any previous psychiatric hospitalization and among all mothers. Within 90 d after delivery, 892 women (1.2 per 1,000 births; 4.84 per 1,000 person-years were hospitalized due to psychoses and 436 of these (0.6 per 1,000 births; 2.38 per 1,000 person-years had not previously been hospitalized for any psychiatric disorder. During follow-up after the 90 d postpartum period, the corresponding incidence rates per 1,000 person-years were reduced to 0.65 for all women and 0.49 for women not previously hospitalized. During (but not after the first 90 d postpartum the risk of psychoses among women without any previous psychiatric hospitalization was independently affected by: maternal age (35 y or older versus 19 y or younger; hazard ratio 2.4, 95% confidence interval [CI] 1.2 to 4.7; high birth weight (> or = 4,500 g; hazard ratio 0.3, 95% CI 0.1 to 1.0; and diabetes (hazard ratio 0. CONCLUSIONS: The incidence of psychotic illness peaks immediately following a first childbirth, and almost 50% of the cases are women without any previous psychiatric hospitalization. High maternal age increases the risk while diabetes and high birth weight are associated with reduced risk of first-onset psychoses, distinctly during the postpartum period.

  15. Studies on the Needs of Seismic Base Isolation Concept and its Standardization

    Lee, Min-Seok; Kim, Jong-Hae [Korea Electric Association, Seoul (Korea, Republic of)


    In the late 1970s, seismic resistance design was introduced as a new design concept through the construction of nuclear power plants. Before this, lateral forces other than wind loads, such as seismic forces, were not taken into consideration in the structural design process. However, in response to the building of increasingly large and heavy structures such as nuclear power plants, a consensus began to form in society regarding the importance of seismic resistance design to avoid a largescale calamity. Since then, Korea has reinforced the relevant regulations, and there has been some progress. At the same time, the seismic base isolation concept was introduced to encourage active research activities related to building safety issues. It has lately been applied for the purpose of reducing construction costs. In 1980s, seismic base isolation design was applied for 'Cruas' plant in France and 'Koeberg' plant in South Africa. Those two are the few cases in which the seismic base isolation design was applied; for the rest, seismic resistance design was applied in most nuclear power plants that are in operation and in construction in the world. Rather than welcoming innovative technology on a trial basis, nuclear power plant design makes use only of proven technologies, which explains the application of seismic resistance design. As seismic base isolation design has become more accepted for use in the building of domestic general bridges, which has, thereby, confirmed its safety, it has been accepted for nuclear power plant design and has even been actively applied. So far, most structures of nuclear facility have been constructed with seismic resistance design and engineering methods. However, seismic force prediction is not perfect in reality; nor is it financially beneficial to apply the system for gradually increasing seismic resistance design loads. Therefore, it is necessary to apply a seismic base isolation system as a way to help secure the

  16. A seismic reflection and GLORIA study of compressional deformation in the Gorringe Bank region, eastern North Atlantic

    Hayward, N.; Watts, A. B.; Westbrook, G. K.; Collier, J. S.


    Seismic reflection and GLORIA side-scan sonar data obtained on RRS Charles Darwin cruise CD64 reveal new information on the styles of deformation in the Gorringe Bank region, at the eastern end of the Azores-Gibraltar plate boundary. Previous studies suggest that Gorringe Bank was formed by the overthrusting of a portion of the African plate upon the Eurasian plate. The new seismic data show, however, that the most intensely deformed region is located south of Gorringe Bank, on the northern flanks of a NW-SE-trending submarine ridge which includes the Ampere and Coral Patch seamounts. The deformation is expressed as long-wavelength (up to 60 km), large-amplitude (up to 800 m) folds in the sediments and underlying acoustic basement, which in places are associated with one or more reverse faults, and as a fabric of short-wavelength folds (up to 3 km) with a NE trend. In contrast, the same sedimentary units when traced beneath the flanking plains are undeformed, except for some faults with a small throw (~30 m), some of which offset the seafloor. GLORIA data show that recent deformation is broadly distributed over the region. Structural trends rotate from 45 deg in the west to 70 deg in the east of the region, nearly perpendicular to the NW-verging plate motion vectors as determined from plate kinematic models. Flexure modelling suggests that a portion of Gorringe Bank has loaded 152 Ma oceanic lithosphere and that a maximum of 50 km of shortening has occurred at Gorringe Bank since the mid-Miocene. Our observations support a model in which there is no single plate boundary in the region, rather that the deformation is distributed over a 200-330 km wide zone.

  17. Probabilistic seismic hazard study based on active fault and finite element geodynamic models

    Kastelic, Vanja; Carafa, Michele M. C.; Visini, Francesco


    We present a probabilistic seismic hazard analysis (PSHA) that is exclusively based on active faults and geodynamic finite element input models whereas seismic catalogues were used only in a posterior comparison. We applied the developed model in the External Dinarides, a slow deforming thrust-and-fold belt at the contact between Adria and Eurasia.. is the Our method consists of establishing s two earthquake rupture forecast models: (i) a geological active fault input (GEO) model and, (ii) a finite element (FEM) model. The GEO model is based on active fault database that provides information on fault location and its geometric and kinematic parameters together with estimations on its slip rate. By default in this model all deformation is set to be released along the active faults. The FEM model is based on a numerical geodynamic model developed for the region of study. In this model the deformation is, besides along the active faults, released also in the volumetric continuum elements. From both models we calculated their corresponding activity rates, its earthquake rates and their final expected peak ground accelerations. We investigated both the source model and the earthquake model uncertainties by varying the main active fault and earthquake rate calculation parameters through constructing corresponding branches of the seismic hazard logic tree. Hazard maps and UHS curves have been produced for horizontal ground motion on bedrock conditions VS 30 ≥ 800 m/s), thereby not considering local site amplification effects. The hazard was computed over a 0.2° spaced grid considering 648 branches of the logic tree and the mean value of 10% probability of exceedance in 50 years hazard level, while the 5th and 95th percentiles were also computed to investigate the model limits. We conducted a sensitivity analysis to control which of the input parameters influence the final hazard results in which measure. The results of such comparison evidence the deformation model and

  18. Simplified seismic risk analysis

    Pellissetti, Manuel; Klapp, Ulrich [AREVA NP GmbH, Erlangen (Germany)


    for this selection is therefore proposed in this paper and its validity is benchmarked against case studies for which a full seismic PSA has been performed in AREVA. (orig.)

  19. A multicenter phase II study of irinotecan in patients with advanced colorectal cancer previously treated with 5-fluorouracil.

    Méndez, Miguel; Salut, Antonieta; García-Girón, Carlos; Navalon, Marta; Diz, Pilar; García López, Maria José; España, Pilar; de la Torre, Ascensión; Martínez del Prado, Purificación; Duarte, Isabel; Pujol, Eduardo; Arizcun, Alberto; Cruz, Juan Jesús


    This multicenter, open-label, phase II study was performed to assess the efficacy and toxicity of irinotecan 350 mg/m2 intravenously every 3 weeks in patients with advanced colorectal cancer (CRC) previously treated with 5-fluorouracil (5-FU). The study enrolled 115 patients and a total of 558 cycles (median, 6 per patient) were administered. The overall objective response rate on an intent-to-treat basis was 18% (with 1 complete response and 20 partial responses), whereas 42 patients (37%) showed stable disease. Median time to progression was 4.8 months and median survival was 13.6 months. Grade 3/4 toxicities included delayed diarrhea (19.1%), nausea/vomiting (10.4%), and neutropenia (8.7%). There were 2 toxic deaths, 1 from delayed diarrhea and 1 from hemorrhage and grade 4 mucositis. In conclusion, the present study confirms the antitumor efficacy of irinotecan monotherapy in patients with CRC pretreated with 5-FU.

  20. Seismic refraction study of the continental edge off the eastern united states

    Sheridan, R.E.; Grow, J.A.; Behrendt, John C.; Bayer, K.C.


    East Coast Magnetic Anomaly landward of the shelf edge off New Jersey and with previous seismic reflection data which reveal extensive outbuilding of the shelf edge during the Jurassic and Lower Cretaceous, probably by carbonate bank-margin accretion. ?? 1979.

  1. Experimental illustrations of seismic-wave properties of interest for hydrogeological studies

    Bodet, L.; Pasquet, S.; Bergamo, P.; Martin, R.; Mourgues, R.; Tournat, V.


    The joint study of pressure (P-) and shear (S-) wave velocities (VP and VS, respectively), as well as their ratio (VP/VS), has been used for many years at large scales (compared to near-surface applications) to study fluids in earth materials. Theoretical and experimental developments have been aimed at understanding the effect of saturation and pore fluids on body wave velocities, more particularly in consolidated media. In the field of hydrocarbon exploration for instance, the measurement of VP/VS ratio helps discriminating different pore fluids in reservoirs. But it is only until recently that this approach has been successfully applied to the characterization of hydrosystems. We showed, thanks to controlled field experiments, the ability of VP/VS ratio in imaging spatial and/or temporal variations of water content at the critical zone scale. These promising results still lack quantitative links between water saturation and seismic properties in such materials and context. We consequently developed laboratory experiments to simulate seismic acquisitions on small-scale controlled granular media with varying water levels. The first results clearly showed the influence of the water level on first arrival times, dispersion and amplitude of the recorded wavefields, and how these measurements could be used as monitoring tools.

  2. Study on Repaired Earthquake-Damaged Bridge Piers under Seismic Load

    Jun Deng


    Full Text Available The concrete bridge pier damaged during earthquakes need be repaired to meet the design standards. Steel tube as a traditional material or FRP as a novel material has become popular to repair the damaged reinforced concrete (RC bridge piers. In this paper, experimental and finite element (FE studies are employed to analyze the confinement effectiveness of the different repair materials. The FE method was used to calculate the hysteretic behavior of three predamaged circle RC bridge piers repaired with steel tube, basalt fiber reinforced polymer (BFRP, and carbon fiber reinforced polymer (CFRP, respectively. Meanwhile, the repaired predamaged circle concrete bridge piers were tested by pseudo-static cyclic loading to study the seismic behavior and evaluate the confinement effectiveness of the different repair materials and techniques. The FE analysis and experimental results showed that the repaired piers had similar hysteretic curves with the original specimens and all the three repair techniques can restore the seismic performance of the earthquake-damaged piers. Steel tube jacketing can significantly improve the lateral stiffness and peak load of the damaged pier, while the BFRP and CFRP sheets cannot improve these properties due to their thin thickness.

  3. Deterministic Seismic Hazard Assessment at Bed Rock Level: Case Study for the City of Bhubaneswar, India

    Sukanti Rout


    Full Text Available In this study an updated deterministic seismic hazard contour map of Bhubaneswar (20°12'0"N to 20°23'0"N latitude and 85°44'0"E to 85° 54'0"E longitude one of the major city of India with tourist importance, has been prepared in the form of spectral acceleration values. For assessing the seismic hazard, the study area has been divided into small grids of size 30˝×30˝ (approximately 1.0 km×1.0 km, and the hazard parameters in terms of spectral acceleration at bedrock level, PGA are calculated as the center of each of these grid cells by considering the regional Seismo-tectonic activity within 400 km radius around the city center. The maximum credible earthquake in terms of moment magnitude of 7.2 has been used for calculation of hazard parameter, results in PGA value of 0.017g towards the northeast side of the city and the corresponding maximum spectral acceleration as 0.0501g for a predominant period of 0.05s at bedrock level.

  4. Numerical analysis on seismic behavior of railway earth embankment:A case study

    林宇亮; 石峰; 杨啸; 杨果林; 李丽民


    A numerical case study on the seismic behavior of embankment was carried out based on a prototype of earth embankment in Yun−Gui Railway (from Kunming City to Nanning City) in southwest of China. A full-scale model of earth embankment was established by means of numerical simulation with FLAC3D code. The numerical results were verified by shaking table test. The seismic behaviors of earth embankment were studied, including the horizontal acceleration response, the vertical acceleration response, the dynamic displacement response, and the block state of earth embankment. Results show that the acceleration magnification near the embankment slope is larger than that in internal earth embankment body. With the increase of input peak acceleration, the horizontal acceleration magnification presents a decreasing trend. The horizontal acceleration response at the top of embankment is more sensitive to the intensity of ground motion than that at the bottom of embankment. The embankment presents an obvious nonlinear-plastic characteristic when the input horizontal peak acceleration is larger than 0.3 g. The maximum residual deformation occurs in the middle of embankment slope surface instead of at the top of embankment. The upper part of embankment experiences tension failure without shear failure, and area at the bottom of embankment around the symmetry-axis of embankment mainly presents shear failure under the earthquake loading. The tension failure and shear failure repeatedly occur along the slope surface of earth embankment.

  5. Study of seismic activity during the ascending and descending phases of solar activity

    Sukma, Indriani; Abidin, Zamri Zainal


    The study of the solar cycle and geomagnetic index associated with the seismic activity from the year 1901 to the end of 2015 has been done for an area that covers the majority of China and its bordering countries. Data of sunspot number, solar wind speed, daily storm time index and earthquake number are collected from NOAA, NASA, WDC, OMNI and USGS databases and websites. The earthquakes are classified into small (M < 5) and large (M ≥ 5) magnitudes (in Richter scale). We investigated the variation of earthquake activities with the geomagnetic storm index due to the solar wind. We focused on their variation in the ascending and descending phases of solar cycle. From our study, we conclude that there is a correlation between the phases' geomagnetic index and solar wind speed. We have also suggested that there is a certain degree of correlation between solar activity and seismicity in these phases. For every solar cycle, we find that there is a trend for earthquakes to occur in greater numbers during the descending phase. This can be explained by the increment in the solar wind speed and geomagnetic storm index during this phase.

  6. Study on Mechanical Characteristics of Fully Grouted Rock Bolts for Underground Caverns under Seismic Loads

    Guoqing Liu


    Full Text Available This study establishes an analytical model for the interaction between the bolt and surrounding rock based on the bearing mechanism of fully grouted rock bolts. The corresponding controlled differential equation for load transfer is deduced. The stress distributions of the anchorage body are obtained by solving the equations. A dynamic algorithm for the bolt considering shear damage on the anchoring interface is proposed based on the dynamic finite element method. The rationality of the algorithm is verified by a pull-out test and excavation simulation of a rounded tunnel. Then, a case study on the mechanical characteristics of the bolts in underground caverns under seismic loads is conducted. The results indicate that the seismic load may lead to stress originating from the bolts and damage on the anchoring interface. The key positions of the antiseismic support can be determined using the numerical simulation. The calculated results can serve as a reference for the antiseismic optimal design of bolts in underground caverns.

  7. Upgrading of seismic design of nuclear power plant building

    Akiyama, Hiroshi [Tokyo Univ. (Japan). Faculty of Engineering; Kitada, Yoshio


    In Japan seismic design methodology of nuclear power plant (NPP) structures has been established as introduced in the previous session. And yet efforts have been continued to date to upgrade the methodology, because of conservative nature given to the methodology in regard to unknown phenomena and technically-limited modeling involved in design analyses. The conservative nature tends to produce excessive safety margins, and inevitably send NPP construction cost up. Moreover, excessive seismic design can increase the burden on normal plant operation, though not necessarily contributing to overall plant safety. Therefore, seismic engineering has put to many tests and simulation analyses in hopes to rationalize seismic design and enhance reliability of seismic safety of NPPs. In this paper, we describe some studies on structural seismic design of NPP underway as part of Japan`s effort to upgrade existing seismic design methodology. Most studies described here are carried out by NUPEC (Nuclear Power Engineering Company) funded by MITI (the Ministry of International Trade and Industry Japan), though, similar studies with the same motive are also carrying out by nuclear industries such as utilities, NPP equipment and system manufacturers and building constructors. This paper consists of three sections, each introducing studies relating to NPP structural seismic design, new siting technology, and upgrading of the methodology of structural design analyses. (J.P.N.)

  8. A comparative study of seismic provisions between International Building Code 2003 and Uniform Building Code 1997

    Wenshen Pong; Zu-Hsu Lee; Anson Lee


    This study focuses on the comparison of the Uniform Building Code (UBC) 1997 and International Building Code (IBC) 2003 in relation to the seismic design and analysis of special steel moment resisting frame buildings (SMRF).This paper formulates a numerical study of a steel SMRF building, studied in four different situations, namely: as an office building in San Francisco; as an office building in Sacramento; as an essential facility in San Francisco, and as an essential facility in Sacramento. The analytical results of the model buildings are then compared and analyzed taking note of any significant differences. This case study explores variations in the results obtained using the two codes, particularly the design base shear and drift ratios as they relate to different locations and occupancy use. This study also proves that IBC 2003is more stringent for the redundancy factor under design category E for the SMRF building, and drift limits for essential facilities.

  9. Outcomes of induction of labour in women with previous caesarean delivery: a retrospective cohort study using a population database.

    Sarah J Stock

    Full Text Available BACKGROUND: There is evidence that induction of labour (IOL around term reduces perinatal mortality and caesarean delivery rates when compared to expectant management of pregnancy (allowing the pregnancy to continue to await spontaneous labour or definitive indication for delivery. However, it is not clear whether IOL in women with a previous caesarean section confers the same benefits. The aim of this study was to describe outcomes of IOL at 39-41 weeks in women with one previous caesarean delivery and to compare outcomes of IOL or planned caesarean delivery to those of expectant management. METHODS AND FINDINGS: We performed a population-based retrospective cohort study of singleton births greater than 39 weeks gestation, in women with one previous caesarean delivery, in Scotland, UK 1981-2007 (n = 46,176. Outcomes included mode of delivery, perinatal mortality, neonatal unit admission, postpartum hemorrhage and uterine rupture. 40.1% (2,969/7,401 of women who underwent IOL 39-41 weeks were ultimately delivered by caesarean. When compared to expectant management IOL was associated with lower odds of caesarean delivery (adjusted odds ratio [AOR] after IOL at 39 weeks of 0.81 [95% CI 0.71-0.91]. There was no significant effect on the odds of perinatal mortality but greater odds of neonatal unit admission (AOR after IOL at 39 weeks of 1.29 [95% CI 1.08-1.55]. In contrast, when compared with expectant management, elective repeat caesarean delivery was associated with lower perinatal mortality (AOR after planned caesarean at 39 weeks of 0.23 [95% CI 0.07-0.75] and, depending on gestation, the same or lower neonatal unit admission (AOR after planned caesarean at 39 weeks of 0.98 [0.90-1.07] at 40 weeks of 1.08 [0.94-1.23] and at 41 weeks of 0.77 [0.60-1.00]. CONCLUSIONS: A more liberal policy of IOL in women with previous caesarean delivery may reduce repeat caesarean delivery, but increases the risks of neonatal complications.

  10. 3D geological to geophysical modelling and seismic wave propagation simulation: a case study from the Lalor Lake VMS (Volcanogenic Massive Sulphides) mining camp

    Miah, Khalid; Bellefleur, Gilles


    The global demand for base metals, uranium and precious metals has been pushing mineral explorations at greater depth. Seismic techniques and surveys have become essential in finding and extracting mineral rich ore bodies, especially for deep VMS mining camps. Geophysical parameters collected from borehole logs and laboratory measurements of core samples provide preliminary information about the nature and type of subsurface lithologic units. Alteration halos formed during the hydrothermal alteration process contain ore bodies, which are of primary interests among geologists and mining industries. It is known that the alteration halos are easier to detect than the ore bodies itself. Many 3D geological models are merely projection of 2D surface geology based on outcrop inspections and geochemical analysis of a small number of core samples collected from the area. Since a large scale 3D multicomponent seismic survey can be prohibitively expensive, performance analysis of such geological models can be helpful in reducing exploration costs. In this abstract, we discussed challenges and constraints encountered in geophysical modelling of ore bodies and surrounding geologic structures from the available coarse 3D geological models of the Lalor Lake mining camp, located in northern Manitoba, Canada. Ore bodies in the Lalor lake VMS camp are rich in gold, zinc, lead and copper, and have an approximate weight of 27 Mt. For better understanding of physical parameters of these known ore bodies and potentially unknown ones at greater depth, we constructed a fine resolution 3D seismic model with dimensions: 2000 m (width), 2000 m (height), and 1500 m (vertical depth). Seismic properties (P-wave, S-wave velocities, and density) were assigned based on a previous rock properties study of the same mining camp. 3D finite-difference elastic wave propagation simulation was performed in the model using appropriate parameters. The generated synthetic 3D seismic data was then compared to

  11. A comparative study of seismicity statistics in laboratory stick-slip experiments and nature: Implications for fault mechanics

    Goebel, Thomas; Kwiatek, Grzegorz; Becker, Thorsten; Sammis, Charles; Dresen, Georg


    Fault properties can rarely be monitored under in-situ conditions at seismogenic depth. At these depths seismicity records are possibly the only high-resolution data that can provide insight into state of stress and mechanics of faulting. We analyze series of laboratory experiments on faults that developed during stick-slip on saw-cut and fractured surfaces under upper crustal stress conditions. Stick-slip experiments were performed on surfaces with varying roughness and fracture surfaces that evolved into fault zones with pronounced damage zones. We monitor and analyze acoustic emission events that exhibit many striking similarities to natural seismicity across all examined scales. These similarities include pronounced Gutenberg-Richter-type magnitude distributions, Omori-type aftershock decay, and off-fault seismicity distributions that decay as a power law with distance. In the laboratory, fault roughness and heterogeneity are critical in concentrating stresses that lead to local AE clustering, and differences in off-fault activities and lower b-values. Similar observations of earthquake clustering and b-value variations were made for natural faults such as the Parkfield segment of the San Andreas fault. In addition to seismicity statistics, we conducted a detailed analysis of moment tensors, focusing on relative contributions from isotropic and deviatoric components to laboratory seismicity. In contrast to natural seismicity, our results revealed a larger contribution from isotropic components. These contributions are a result of ongoing fracture processes within the evolving fault which are most pronounced after stick-slip events. Our study shows, that seismicity analyses in laboratory experiments can significantly advance our understanding of fault mechanics from the scale of single asperities to large fault zones.

  12. Birth outcome in women with previously treated breast cancer--a population-based cohort study from Sweden.

    Kristina Dalberg


    Full Text Available BACKGROUND: Data on birth outcome and offspring health after the appearance of breast cancer are limited. The aim of this study was to assess the risk of adverse birth outcomes in women previously treated for invasive breast cancer compared with the general population of mothers. METHODS AND FINDINGS: Of all 2,870,932 singleton births registered in the Swedish Medical Birth Registry during 1973-2002, 331 first births following breast cancer surgery--with a mean time to pregnancy of 37 mo (range 7-163--were identified using linkage with the Swedish Cancer Registry. Logistic regression analysis was used. The estimates were adjusted for maternal age, parity, and year of delivery. Odds ratios (ORs and 95% confidence intervals (CIs were used to estimate infant health and mortality, delivery complications, the risk of preterm birth, and the rates of instrumental delivery and cesarean section. The large majority of births from women previously treated for breast cancer had no adverse events. However, births by women exposed to breast cancer were associated with an increased risk of delivery complications (OR 1.5, 95% CI 1.2-1.9, cesarean section (OR 1.3, 95% CI 1.0-1.7, very preterm birth (<32 wk (OR 3.2, 95% CI 1.7-6.0, and low birth weight (<1500 g (OR 2.9, 95% CI 1.4-5.8. A tendency towards an increased risk of malformations among the infants was seen especially in the later time period (1988-2002 (OR 2.1, 95% CI 1.2-3.7. CONCLUSIONS: It is reassuring that births overall were without adverse events, but our findings indicate that pregnancies in previously treated breast cancer patients should possibly be regarded as higher risk pregnancies, with consequences for their surveillance and management.

  13. Seismic Experimental Study on New-Type Composite Exterior Wallboard with Integrated Structural Function and Insulation

    Shaochun Ma


    Full Text Available In order to evaluate the seismic performance of new-type composite exterior wallboard, a total of six exterior and interior wallboards were incorporated in the experiment of seismic performance. Seismic performance such as the stress process, damage mode, hysteresis and skeleton curve, load-carrying and ductility coefficient, damping and energy dissipation, stiffness degradation as well as material strain of the exterior wallboards were analyzed with emphasis and compared with interior wallboards. Results of the experiment and analysis showed that both interior and exterior wallboards exhibited outstanding seismic performance. Due to the existence of insulation layer and externally bonded single gypsum board, the capacity of elastoplastic deformation and seismic energy dissipation of the exterior wallboards was improved and each seismic performance indicator of the exterior wallboards outperformed the interior wallboards.

  14. Does the previous diagnosis of arterial hypertension affect one´s daily life? Pró-Saúde Study

    Gilberto Senechal de Goffredo Filho


    Full Text Available In addition to damaging several target organs, arterial hypertension may negatively impact patients' activities of daily living. Biological and behavioral mechanisms underlying such limitations have yet to be clarified. The objectives of this study were to investigate whether having been previously told of a hypertension diagnosis is associated with the frequency and duration of temporary limitations in activities of daily living, and whether these relationships differ by gender, age, or socioeconomic position. We analyzed sectional data from 2,666 participants (56% women; 55% with high school or lower schooling at the baseline phase (1999 - 2001 of a longitudinal investigation of university employees in Rio de Janeiro, Brazil (Pró-Saúde Study, asking participants whether they had ever been diagnosed with hypertension by a health professional, if they had been unable to perform any activities of daily living due to a health problem in the previous 2 weeks, and for how many days that had occurred. Multinomial logistic regression models were fitted for the overall study population and for age, gender, educational level, and per capita household income strata. Associations between hypertension diagnosis and temporary limitations were not observed in the overall study population and in gender, education and income strata. However, there were higher odds of temporary limitations among participants aged 55 years old or more with hypertension diagnosis (adjusted OR = 9.5; 95%CI 1.5 - 58.6, regardless of blood pressure levels and use of antihypertensive medication. Elderly people may keep an attitude of higher vigilance regarding conditions or events potentially worsening their health status.

  15. Seismic activity parameters of the Finnish potential repository sites

    Saari, J. [Fortum Engineering Oy, Vantaa (Finland)


    Posiva Oy has started a project for estimating the possible earthquake induced rock movements on the deposition holes containing canisters of spent nuclear fuel. These estimates will be made for the four investigation sites, Romuvaara, Kivetty, Olkiluoto and Haestholmen. This study deals with the current and future seismicity associated with the above mentioned sites. Seismic belts that participate the seismic behaviour of the studied sites have been identified and the magnitude-frequency distributions of these belts have been estimated. The seismic activity parameters of the sites have been deduced from the characteristics of the seismic belts in order to forecast the seismicity during the next 100,000 years. The report discusses the possible earthquakes induced by future glaciation. The seismic interpretation seems to indicate that the previous postglacial faults in Finnish Lapland have been generated in compressional environment. The orientation of the rather uniform compression has been NW-SE, which coincide with the current stress field. It seems that, although the impact of postglacial crustal rebound must have been significant, the impact of plate tectonics has been dominant. A major assumption of this study has been that future seismicity will generally resemble the current seismicity. However, when the postglacial seismicity is concerned, the magnitude-frequency distribution is likely different and the expected maximum magnitude will be higher. Maximum magnitudes of future postglacial earthquakes have been approximated by strain release examinations. Seismicity has been examined within the framework of the lineament maps, in order to associate the future significant earthquakes with active fault zones in the vicinity of the potential repository sites. (orig.)

  16. Seismic energy dissipation study of linear fluid viscous dampers in steel structure design

    A. Ras


    Full Text Available Energy dissipation systems in civil engineering structures are sought when it comes to removing unwanted energy such as earthquake and wind. Among these systems, there is combination of structural steel frames with passive energy dissipation provided by Fluid Viscous Dampers (FVD. This device is increasingly used to provide better seismic protection for existing as well as new buildings and bridges. A 3D numerical investigation is done considering the seismic response of a twelve-storey steel building moment frame with diagonal FVD that have linear force versus velocity behaviour. Nonlinear time history, which is being calculated by Fast nonlinear analysis (FNA, of Boumerdes earthquake (Algeria, May 2003 is considered for the analysis and carried out using the SAP2000 software and comparisons between unbraced, braced and damped structure are shown in a tabulated and graphical format. The results of the various systems are studied to compare the structural response with and without this device of the energy dissipation thus obtained. The conclusions showed the formidable potential of the FVD to improve the dissipative capacities of the structure without increasing its rigidity. It is contributing significantly to reduce the quantity of steel necessary for its general stability.

  17. Earthquake hazard in northeast India – A seismic microzonation approach with typical case studies from Sikkim Himalaya and Guwahati city

    Sankar Kumar Nath; Kiran Kumar Singh Thingbaijam; Abhishek Raj


    A comprehensive analytical as well as numerical treatment of seismological, geological, geomorphological and geotechnical concepts has been implemented through microzonation projects in the northeast Indian provinces of Sikkim Himalaya and Guwahati city, representing cases of contrasting geological backgrounds – a hilly terrain and a predominantly alluvial basin respectively. The estimated maximum earthquakes in the underlying seismic source zones, demarcated in the broad northeast Indian region, implicates scenario earthquakes of 8.3 and 8.7 to the respective study regions for deterministic seismic hazard assessments. The microzonation approach as undertaken in the present analyses involves multi-criteria seismic hazard evaluation through thematic integration of contributing factors. The geomorphological themes for Sikkim Himalaya include surface geology, soil cover, slope, rock outcrop and landslide integrated to achieve geological hazard distribution. Seismological themes, namely surface consistent peak ground acceleration and predominant frequency were, thereafter, overlaid on and added with the geological hazard distribution to obtain the seismic hazard microzonation map of the Sikkim Himalaya. On the other hand, the microzonation study of Guwahati city accounts for eight themes – geological and geomorphological, basement or bedrock, landuse, landslide, factor of safety for soil stability, shear wave velocity, predominant frequency, and surface consistent peak ground acceleration. The five broad qualitative hazard classifications – `low’, `moderate’, `high’, `moderate high’ and `very high’ could be applied in both the cases, albeit with different implications to peak ground acceleration variations. These developed hazard maps offer better representation of the local specific seismic hazard variation in the terrain.

  18. Study of seismic design bases and site conditions for nuclear power plants


    This report presents the results of an investigation of four topics pertinent to the seismic design of nuclear power plants: Design accelerations by regions of the continental United States; review and compilation of design-basis seismic levels and soil conditions for existing nuclear power plants; regional distribution of shear wave velocity of foundation materials at nuclear power plant sites; and technical review of surface-founded seismic analysis versus embedded approaches.

  19. Study of seismic hazard mitigation at different time scales: applications and technological development

    Caccavale, Mauro


    Earthquakes, weak or strong, represent always a psychological and emotional stress for people, but also a strong socio-economic impact for the affected area. The earthquake generation, the propagation of seismic waves, the seismic waves modification due to the propagation media and the interaction between seismic wave and human structures, are the main topics of different research disciplines. In the last years a wide interdisciplinary research program (physics, seismology, mathematics, geolo...

  20. Predicting DUI recidivism of male drunken driving: a prospective study of the impact of alcohol markers and previous drunken driving.

    Portman, M; Penttilä, A; Haukka, J; Eriksson, P; Alho, H; Kuoppasalmi, K


    The aim of the present study was to determine whether the alcohol biomarkers CDT, GGT, the biomarker gamma-CDT index and previous drunken driving contributed significantly to the prediction of DUI recidivism. The subjects consisted of two different samples of drivers, viz. drivers who were found to have a positive breath alcohol concentration during random breath testing surveys (n=237), and drunken drivers who were apprehended during ordinary police work (n=193). The drunken driving events were monitored using a data-base both retrospectively and prospectively. It was found that the biomarker index, gamma-CDT, emerged as a notable predictor of recidivism in the group of random breath tested drivers. Measurement of gamma-CDT and its impact on DUI recidivism has not to our knowledge been applied to random breath tested drivers before. The apprehended drunken drivers, on the other hand, did not show a significant relationship between gamma-CDT and DUI recidivism. However, in both groups of drivers it was found that a previous conviction for drunken driving strongly predicted DUI recidivism. More attention should be paid by both physicians and the police to the high risk of recidivism among those convicted of drunken driving.

  1. Assessment of wind turbine seismic risk : existing literature and simple study of tower moment demand.

    Prowell, Ian (University of California, San Diego, CA); Veers, Paul S.


    Various sources of risk exist for all civil structures, one of which is seismic risk. As structures change in scale, the magnitude of seismic risk changes relative to risk from other sources. This paper presents an introduction to seismic hazard as applied to wind turbine structures. The existing design methods and research regarding seismic risk for wind turbines is then summarized. Finally a preliminary assessment is made based on current guidelines to understand how tower moment demand scales as rated power increases. Potential areas of uncertainty in the application of the current guidelines are summarized.

  2. A Review on the Study of "Repeating Earthquakes" by Cross-correlation of Seismic Waveforms~%A Review on the Study of "Repeating Earthquakes" by Cross-correlation of Seismic Waveforms~

    Li Yutong; Jiang Changsheng


    "Repeating earthquakes", identified by cross-correlation of seismic waveforms, are found to be much more abundant in the nature than conventionally expected. In recent years, with the development of digital seismic networks, waveform cross correlation and "repeating earthquakes" have caused much attention to the measuring the variation of crustal medium properties and estimation of location accuracy and fault slip rate at depth or earthquake recurrence intervals. Moreover, as a useful tool, the "repeating earthquake" approach has also been used in the assessment of the accuracy of seismic phase picking, hypocenter location, fault structure and physics of earthquake sources, as well as the study of earthquake prediction. In this paper, we summarized the latest research and applications of "repeating earthquakes".

  3. The suitability of XRF analysis for compositional classification of archaeological ceramic fabric: A comparison with a previous NAA study

    Padilla, R. [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Laboratorio de Analisis Quimico, Calle 30 no. 502, Playa, Ciudad Habana (Cuba)]. E-mail:; Espen, P. van [University of Antwerp (Belgium); Torres, P.P. Godo [Centro de Antropologia, Havana (Cuba)


    The main drawbacks of EDXRF techniques, restricting its more frequent use for the specific purpose of compositional analysis of archaeological ceramic fabric, have been the insufficient sensitivity to determine some important elements (like Cr, REE, among others), a somewhat worse precision and the inability to perform standard-less quantitative procedures in the absence of suitable certified reference materials (CRM) for ceramic fabric. This paper presents the advantages of combining two energy dispersive X-ray fluorescence methods for fast and non-destructive analysis of ceramic fabric with increased sensitivity. Selective polarized excitation using secondary targets (EDPXRF) and radioisotope excitation (R-XRF) using a {sup 241}Am source. The analytical performance of the methods was evaluated by analyzing several CRM of sediment type, and the fitness for the purpose of compositional classification was compared with that obtained by using Instrumental Neutron Activation Analysis in a previous study of Cuban aborigine pottery.

  4. Study on Anti-Disturbance and High-Resolution Shallow Seismic Exploration of Active Faults in Urban Regions

    Pan Jishun; Zhang Xiankang; Liu Baojin; Fan Shengming; Wang Fuyun; Duan Yonghong; Zhang Hongqiang


    The significance of detection of urban active faults and the general situation concerning detection of urban active faults in the world are briefly introduced. In a brief description of the basic principles of anti-disturbance and high-resolution shallow seismic exploration, the stress is put on the excitation of seismic sources, the performance of digital seismographs, receiving mode and conditions, geometry as well as data acquisition, processing and interpretation in the anti-disturbance and high-resolution shallow seismic exploration of urban active faults. The study indicates that a controlled seismic source with a linear or nonlinear frequency-conversion scanning function and the relevant seismographs must be used in data acquisition, as well as working methods for small group interval, small offset, multi-channel receiving, short-array and high-frequency detectors for receiving are used. Attention should be paid to the application of techniques for static correction of refraction, noise suppressing, high-precision analysis of velocity, wavelet compressing, zero-phasing of wavelet and pre-stacking migration to data processing and interpretation. Finally, some cases of anti-disturbance and high-resolution shallow seismic exploration of urban active faults are present in the paper.

  5. Evaluation of questionnaire-based information on previous physical work loads. Stockholm MUSIC 1 Study Group. Musculoskeletal Intervention Center.

    Torgén, M; Winkel, J; Alfredsson, L; Kilbom, A


    The principal aim of the present study was to evaluate questionnaire-based information on past physical work loads (6-year recall). Effects of memory difficulties on reproducibility were evaluated for 82 subjects by comparing previously reported results on current work loads (test-retest procedure) with the same items recalled 6 years later. Validity was assessed by comparing self-reports in 1995, regarding work loads in 1989, with worksite measurements performed in 1989. Six-year reproducibility, calculated as weighted kappa coefficients (k(w)), varied between 0.36 and 0.86, with the highest values for proportion of the workday spent sitting and for perceived general exertion and the lowest values for trunk and neck flexion. The six-year reproducibility results were similar to previously reported test-retest results for these items; this finding indicates that memory difficulties was a minor problem. The validity of the questionnaire responses, expressed as rank correlations (r(s)) between the questionnaire responses and workplace measurements, varied between -0.16 and 0.78. The highest values were obtained for the items sitting and repetitive work, and the lowest and "unacceptable" values were for head rotation and neck flexion. Misclassification of exposure did not appear to be differential with regard to musculoskeletal symptom status, as judged by the calculated risk estimates. The validity of some of these self-administered questionnaire items appears sufficient for a crude assessment of physical work loads in the past in epidemiologic studies of the general population with predominantly low levels of exposure.

  6. Probabilistic seismic hazard assessment for Central Asia

    Shahid Ullah


    Full Text Available Central Asia is one of the seismically most active regions in the world. Its complex seismicity due to the collision of the Eurasian and Indian plates has resulted in some of the world’s largest intra-plate events over history. The region is dominated by reverse faulting over strike slip and normal faulting events. The GSHAP project (1999, aiming at a hazard assessment on a global scale, indicated that the region of Central Asia is characterized by peak ground accelerations for 10% probability of exceedance in 50 years as high as 9 m/s2. In this study, carried out within the framework of the EMCA project (Earthquake Model Central Asia, the area source model and different kernel approaches are used for a probabilistic seismic hazard assessment (PSHA for Central Asia. The seismic hazard is assessed considering shallow (depth < 50 km seismicity only and employs an updated (with respect to previous projects earthquake catalog for the region. The seismic hazard is calculated in terms of macroseismic intensity (MSK-64, intended to be used for the seismic risk maps of the region. The hazard maps, shown in terms of 10% probability of exceedance in 50 years, are derived by using the OpenQuake software [Pagani et al. 2014], which is an open source software tool developed by the GEM (Global Earthquake Model foundation. The maximum hazard observed in the region reaches an intensity of around 8 in southern Tien Shan for 475 years mean return period. The maximum hazard estimated for some of the cities in the region, Bishkek, Dushanbe, Tashkent and Almaty, is between 7 and 8 (7-8, 8.0, 7.0 and 8.0 macroseismic Intensity, respectively, for 475 years mean return period, using different approaches. The results of different methods for assessing the level of seismic hazard are compared and their underlying methodologies are discussed.

  7. Discontinuum Modelling Approach for Stress Analysis at a Seismic Source: Case Study

    Sainoki, Atsushi; Mitri, Hani S.; Yao, Mike; Chinnasane, Damodara


    Rockbursts in underground mines can cause devastating damage to mine workings; hence, it is important to be able to assess the potential for their occurrence. The present study focuses on a large seismic event that took place at an underground base metal mine in Canada. The event took place in a dyke near the 100/900 orebodies on 3880 Level (1180 m below surface) of the Copper Cliff Mine in Sudbury, Canada. A 3D continuum stress analysis of the orebodies, i.e., 100 and 900, using an orebody-wide model encompassing the major geological structures and in situ stress heterogeneity in the mine shows low potential for rockburst at the seismic source location—a result which contradicts the fact that a large seismic event actually took place. A postulation is thus made that there had been highly stressed regions caused by geological disturbances at the source location before mining activities took place. In order to verify the postulation, a further study is undertaken with the discrete element modelling technique, whereby a cube-shaped model containing a fracture network is subjected to a stress state similar to that at the source location. A model parametrical study is conducted with respect to the distribution of the fracture (joint) network and its mechanical properties. The results reveal that when joints are densely distributed at the source location, the stress state becomes significantly burst prone. It is observed that the length, density, stiffness, and orientation of joints have a large influence on the stress state along the joints, while the friction angle, cohesion, and tensile strength do not influence the stress state. A cube-shaped model is constructed with joint sets actually mapped at the mine and a stress analysis is performed. The results demonstrate the generation of highly stressed regions due to the interaction of the joints with the applied in situ stress fields, thus leading to burst-prone conditions. The present study numerically confirms that

  8. Crustal structure and mantle transition zone thickness beneath a hydrothermal vent at the ultra-slow spreading Southwest Indian Ridge (49°39'E): a supplementary study based on passive seismic receiver functions

    Ruan, Aiguo; Hu, Hao; Li, Jiabiao; Niu, Xiongwei; Wei, Xiaodong; Zhang, Jie; Wang, Aoxing


    As a supplementary study, we used passive seismic data recorded by one ocean bottom seismometer (OBS) station (49°41.8'E) close to a hydrothermal vent (49°39'E) at the Southwest Indian Ridge to invert the crustal structure and mantle transition zone (MTZ) thickness by P-to-S receiver functions to investigate previous active seismic tomographic crustal models and determine the influence of the deep mantle thermal anomaly on seafloor hydrothermal venting at an ultra-slow spreading ridge. The new passive seismic S-wave model shows that the crust has a low velocity layer (2.6 km/s) from 4.0 to 6.0 km below the sea floor, which is interpreted as partial melting. We suggest that the Moho discontinuity at 9.0 km is the bottom of a layer (2-3 km thick); the Moho (at depth of 6-7 km), defined by active seismic P-wave models, is interpreted as a serpentinized front. The velocity spectrum stacking plot made from passive seismic data shows that the 410 discontinuity is depressed by 15 km, the 660 discontinuity is elevated by 18 km, and a positive thermal anomaly between 182 and 237 K is inferred.

  9. Study on Seismic Control of Power Transmission Tower-Line Coupled System under Multicomponent Excitations

    Li Tian


    Full Text Available The seismic control of power transmission tower-line coupled system subjected to multicomponent excitations is studied in this paper. The schematic of tuned mass damper is introduced, and equations of motion of a system with tuned mass damper under multi-component excitations are proposed. Three-dimensional finite tower-line system models are created based on practical engineering in studying the response of this system without and with control. The time domain analysis takes into account geometric nonlinearity due to finite deformation. The optimal design of the transmission tower-line system with tuned mass damper is obtained according to different mass ratio. The effects of wave travel, coherency loss, and different site conditions on the system without and with control are investigated, respectively.

  10. Alemtuzumab as rescue therapy in a cohort of 16 aggressive multiple sclerosis patients previously treated by Mitoxantrone: an observational study.

    Le Page, Emmanuelle; Deburghgraeve, Véronique; Lester, Marie-Antoinette; Cardiet, Isabelle; Leray, Emmanuelle; Edan, Gilles


    Our study aimed to describe safety and neurological impact of alemtuzumab as last-line rescue therapy in aggressive multiple sclerosis (MS) patients, previously treated by Mitoxantrone (MITOX). Between June 2004 and October 2013, 13 patients received alemtuzumab at 20 mg/day and 3 at 12 mg/day for 5 days. EDSS, relapses, secondary progression were prospectively assessed 12 and 6 months before treatment, at baseline and every 3 months. Mean follow-up was 6.2 years [1-10]. Mean age at alemtuzumab start was 40 years [26-49] for 8 Secondary Progressive (SP) and 30 years [26-35] for 8 Relapsing-Remitting (RR) patients. MS duration was 13.7 (± 3) and 8.3 (± 4) years, respectively. During the 12 months before alemtuzumab, annual relapse rate was 0.75 and 3.14, respectively and the 16 patients accumulated 2-30 new gadolinium enhancing lesions. 4 patients (suboptimal responders) received alemtuzumab during MITOX and 12 patients 1-7.8 years after MITOX. Out of 8 SPMS, 2 were disease free up to last visit (4.7 and 8 years), 5 improved or stabilized but only transiently and 1 worsened. Out of 8 RRMS, 1 remained stable up to last visit (8.7 years) despite 1 relapse and active MRI at 18 months and 7 improved (1-4 point EDSS): 4 remained disease free up to last visit (12, 24, 38 months and 7 years), 2 were successfully retreated at 25 and 33 months and 1 worsened progressively 24 months after alemtuzumab. 2 patients developed Grave's disease and 1 hypothyroidism. Alemtuzumab controls aggressive RRMS despite previous use of MITOX.

  11. Seismic techniques in coal mining

    Bhattacharyya, A.K.; Belleza, G.V.


    The aim of this study is to investigate the peripheral fracture zones in coal pillars left for support in underground mines. The fracture zones are caused by the redistribution of stresses in strata resulting from the process of excavation and blasting if it is used. The extent and degree of these fracture zones, in turn, have a direct influence on the ability of pillars to provide stable support to the overlying strata. Seismic methods such as refraction, uphole, and collinear techniques outlined in previous reports are being used to investigate the extent and degree of the peripheral fracture zones. Some of the work that has been carried out and is described in this report, relates to the study of peripheral fracture zones in coal pillars using seismic techniques.

  12. A feasibility study of time-lapse seismic noise interferometry for CO2 monitoring at Ketzin

    Boullenger, B.; Verdel, A.; Thorbecke, J.; Draganov, D.


    Since 2008, CO2 has been injected at the demonstration site for CO2 sequestration in Ketzin, Germany. Since 2009, a permanent array of seismic receivers installed by TNO at the injection site has recorded passive data continuously. It is the intention of TNO to use seismic interferometry (SI) by cro

  13. 4-D seismic in a complex fluvial reservoir: the Snorre feasibility study

    Smith, P.; Berg, J.I.; Eidsvig, S.; Magnus, I.; Verhelst, F.J.P.C.M.G.; Helgesen, J.


    The saga petroleum, discoverer of Snorre Field, describe's how 3-D seismic surveys are used to determine the value of time-lapse seismic data for field management. Careful examination of the repeatability of the time-lapse data sets, before interpretation stark, establishes a framework defining the

  14. 4-D seismic in a complex fluvial reservoir: the Snorre feasibility study

    Smith, P.; Berg, J.I.; Eidsvig, S.; Magnus, I.; Verhelst, F.J.P.C.M.G.; Helgesen, J.


    The saga petroleum, discoverer of Snorre Field, describe's how 3-D seismic surveys are used to determine the value of time-lapse seismic data for field management. Careful examination of the repeatability of the time-lapse data sets, before interpretation stark, establishes a framework defining the

  15. Subsurface geology of the Lusi region: preliminary results from a comprehensive seismic-stratigraphic study.

    Moscariello, Andrea; Do Couto, Damien; Lupi, Matteo; Mazzini, Adriano


    We investigate the subsurface data of a large sector in the Sidoarjo district (East Java, Indonesia) where the sudden catastrophic Lusi eruption started the 26th May 2006. Our goal is to understand the stratigraphic and structural features which can be genetically related to the surface manifestations of deep hydrothermal fluids and thus allow us to predict possible future similar phenomena in the region. In the framework of the Lusi Lab project (ERC grant n° 308126) we examined a series of densely spaced 2D reflection commercial seismic lines This allowed the reconstruction of the lateral variability of key stratigraphic horizons as well as the main tectonic features. In particular, we shed light on the deep structure of the Watukosek fault system and the associated fracture corridors crossing the entire stratigraphic successions. To the South-West, when approaching the volcanic complex, we could identify a clear contrast in seismic facies between chaotic volcanoclastic wedges and clastic-prone sedimentary successions as well as between the deeper stratigraphic units consisting of carbonates and lateral shales units. The latter show possible ductile deformation associated to fault-controlled diapirism which control in turns deformation of overlying stratigraphic units and deep geo-fluids circulation. Large collapse structures recognized in the study area (e.g. well PRG-1) are interpreted as the results of shale movement at depth. Similarly to Lusi, vertical deformation zones ("pipes"), likely associated with deeply rooted strike-slip systems seem to be often located at the interface between harder carbonate rocks forming isolated build ups and the laterally nearby clastic (shale-prone)-units. The mechanisms of deformation of structural features (strike vs dip slip systems) which may affect either the basement rock or the overlying deeper stratigraphic rocks is also being investigated to understand the relationship between deep and shallower (i.e. meteoric) fluid

  16. From Seismic Scenarios to Earthquake Risk Assessment: A Case Study for Iquique, Chile.

    Aguirre, P.; Fortuno, C.; Martin, J. C. D. L. L.; Vasquez, J.


    Iquique is a strategic city and economic center in northern Chile, and is located in a large seismic gap where a megathrust earthquake and tsunami is expected. Although it was hit by a Mw 8.2 earthquake on April 1st 2014, which caused moderate damage, geophysical evidence still suggests that there is potential for a larger event, so a thorough risk assessment is key to understand the physical, social, and economic effects of such potential event, and devise appropriate mitigation plans. Hence, Iquique has been selected as a prime study case for the implementation of a risk assessment platform in Chile. Our study integrates research on three main elements of risk calculations: hazard evaluation, exposure model, and physical vulnerabilities. To characterize the hazard field, a set of synthetic seismic scenarios have been developed based on plate interlocking and the residual slip potential that results from subtracting the slip occurred during the April 1st 2014 rupture fault mechanism, obtained using InSAR+GPS inversion. Additional scenarios were developed based of the fault rupture model of the Maule 2010 Mw 8.8 earthquake and on the local plate locking models in northern Chile. These rupture models define a collection of possible realizations of earthquake geometries parameterized in terms of critical variables like slip magnitude, rise time, mean propagation velocity, directivity, and other, which are propagated to obtain a hazard map for Iquique (e.g. PGA, PGV, PDG). Furthermore, a large body of public and local data was used to construct a detailed exposure model for Iquique, including aggregated building count, demographics, essential facilities, and lifelines. This model together with the PGA maps for the April 1st 2014 earthquake are used to calibrate HAZUS outputs against observed damage, and adjust the fragility curves of physical systems according to more detailed analyses of typical Chilean building types and their structural properties, plus historical

  17. Study of pre-seismic kHz EM emissions by means of complex systems

    Balasis, Georgios; Papadimitriou, Constantinos; Eftaxias, Konstantinos


    The field of study of complex systems holds that the dynamics of complex systems are founded on universal principles that may used to describe disparate problems ranging from particle physics to economies of societies. A corollary is that transferring ideas and results from investigators in hitherto disparate areas will cross-fertilize and lead to important new results. It is well-known that the Boltzmann-Gibbs statistical mechanics works best in dealing with systems composed of either independent subsystems or interacting via short-range forces, and whose subsystems can access all the available phase space. For systems exhibiting long-range correlations, memory, or fractal properties, non-extensive Tsallis statistical mechanics becomes the most appropriate mathematical framework. As it was mentioned a central property of the magnetic storm, solar flare, and earthquake preparation process is the possible occurrence of coherent large-scale collective with a very rich structure, resulting from the repeated nonlinear interactions among collective with a very rich structure, resulting from the repeated nonlinear interactions among its constituents. Consequently, the non-extensive statistical mechanics is an appropriate regime to investigate universality, if any, in magnetic storm, solar flare, earthquake and pre-failure EM emission occurrence. A model for earthquake dynamics coming from a non-extensive Tsallis formulation, starting from first principles, has been recently introduced. This approach leads to a Gutenberg-Richter type law for the magnitude distribution of earthquakes which provides an excellent fit to seismicities generated in various large geographic areas usually identified as "seismic regions". We examine whether the Gutenberg-Richter law corresponding to a non-extensive Tsallis statistics is able to describe the distribution of amplitude of earthquakes, pre-seismic kHz EM emissions (electromagnetic earthquakes), solar flares, and magnetic storms. The

  18. Comparative in situ X-ray Diffraction Study of San Carlos Olivine: Influence of Water on the 410 km Seismic Velocity Jump in Earth’s Mantle

    J Chen; H Liu; J Girard


    A comparative study of the equation of states of hydrous (0.4 wt% H{sub 2}O) and anhydrous San Carlos olivine (<30 ppm H2O) was conducted using synchrotron X-rays up to 11 GPa in a diamond anvil cell (DAC) at ambient temperature. Both samples were loaded in the same high-pressure chamber of the DAC to eliminate the possible pressure difference in different experiments. The obtained compression data were fitted to the third-order Birch-Murnaghan equation of state, yielding a bulk modulus K{sub 0} = 123(3) GPa for hydrous olivine and K{sub 0} = 130(4) GPa for anhydrous olivine as K{sub 0}' is fixed at 4.6. Therefore, 0.4 wt% H{sub 2}2O in olivine results in a 5% reduction in bulk modulus. Previous studies reported bulk modulus reduction by water in olivine's high-pressure polymorph (wadsleyite), to which the transformation from olivine gives rise to the seismic discontinuity at 410 km depth. The new data results in a reduction in the magnitude of the discontinuity by 50% in v{sub P} and 30% in v{sub S} (for 1:5 water partitioning between olivine and wadsleyite) with respect to anhydrous mantle. Previous knowledge of the influence of water on this phase transition has been in opposition to a large amount of water [e.g., 200 ppm by Wood (1995)] existing at 410 km depth. Calculation of the seismic velocities based on newly available elasticity data of the hydrous phases indicates that the presence of water is favorable for the mineral composition model (pyrolite) and seismic observations in terms of the magnitude of the 410 km discontinuity.

  19. New Seismic Hazard study in Spain Aimed at the revision of the Spanish Building Code

    Rivas-Medina, A.; Benito, B.; Cabañas, L.; Martínez-Solares, J. M.; Ruíz, S.; Gaspar-Escribano, J. M.; Carreño, E.; Crespo, M.; García-Mayordomo, J.


    In this paper we present a global overview of the recent study carried out in Spain for the new hazard map, which final goal is the revision of the Building Code in our country (NCSE-02). The study was carried our for a working group joining experts from The Instituto Geografico Nacional (IGN) and the Technical University of Madrid (UPM) , being the different phases of the work supervised by an expert Committee integrated by national experts from public institutions involved in subject of seismic hazard. The PSHA method (Probabilistic Seismic Hazard Assessment) has been followed, quantifying the epistemic uncertainties through a logic tree and the aleatory ones linked to variability of parameters by means of probability density functions and Monte Carlo simulations. In a first phase, the inputs have been prepared, which essentially are: 1) a project catalogue update and homogenization at Mw 2) proposal of zoning models and source characterization 3) calibration of Ground Motion Prediction Equations (GMPE's) with actual data and development of a local model with data collected in Spain for Mw logic tree and their weights. Finally, the hazard estimation was done with the logic tree shown in figure 1, including nodes for quantifying uncertainties corresponding to: 1) method for estimation of hazard (zoning and zoneless); 2) zoning models, 3) GMPE combinations used and 4) regression method for estimation of source parameters. In addition, the aleatory uncertainties corresponding to the magnitude of the events, recurrence parameters and maximum magnitude for each zone have been also considered including probability density functions and Monte Carlo simulations The main conclusions of the study are presented here, together with the obtained results in terms of PGA and other spectral accelerations SA (T) for return periods of 475, 975 and 2475 years. The map of the coefficient of variation (COV) are also represented to give an idea of the zones where the dispersion among

  20. A phase I study of imatinib mesylate in combination with chlorambucil in previously treated chronic lymphocytic leukemia patients.

    Hebb, Jonathan; Assouline, Sarit; Rousseau, Caroline; Desjardins, Pierre; Caplan, Stephen; Egorin, Merrill J; Amrein, Lilian; Aloyz, Raquel; Panasci, Lawrence


    The tyrosine kinase inhibitor, imatinib, has the potential to indirectly inhibit DNA repair. This mechanism of action has been shown to mediate sensitization to chlorambucil in chronic lymphocytic leukemia (CLL). To evaluate this effect in vivo, we performed a phase I study of chlorambucil combined with imatinib in relapsed CLL patients. The three dose levels studied included imatinib at 300, 400, or 600 mg/day. Imatinib was given on days 1-10, and chlorambucil (8 mg/m(2) daily) was given on days 3-7 of a 28-day cycle (up to 6 cycles). Eleven patients participated in this study. Low-grade gastrointestinal toxicities were observed in a dose-dependent manner. Forty-five percent of patients responded (two unconfirmed CRs and three PRs). Two responding patients were fludarabine refractory. The in vitro IC(50) of chlorambucil alone or in the presence of 5 μM imatinib in CLL lymphocytes correlated with the decrease in lymphocyte counts on day 15. Imatinib plasma concentrations achieved in patients were in the range of those effective in in vitro sensitization studies. The combination of chlorambucil and imatinib in patients with previously treated CLL was well tolerated and showed evidence of clinical efficacy. Based on our results, we recommend the 400 mg daily dose of imatinib on days 1-10 with 8 mg/m(3) chlorambucil on days 3-7 every 28 days as the phase II dose. This represents the first clinical trial examining the potential synergy between a tyrosine kinase inhibitor and a conventional alkylating agent for the treatment of CLL.

  1. A source discrimination study of a Chinese seismic event of May 4, 1983

    Arora, S. K.; Basu, T. K.


    A weak seismic event that occurred on May 4, 1983, close to the Lop Nor underground test site in Southern Sinkiang province, China, has been studied for source discrimination. Digital waveforms, obtained at Gauribidanur array, India, of this event, of six known shallow-focus earthquakes from Southern Sinkiang and of two known underground nuclear explosions in Lop Nor, were processed for further analysis. The estimates of signal complexity and TMF (third moment of frequency) parameters of the May 4 event were found to be quite different from those of the known explosions whereas they were consistent with those of the known earthquakes. On this basis the event under investigation appeared to be a crustal-focus earthquake.



    <正>20091465 Cai Xuelin(College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China);Cao Jiamin Preliminary Study on the 3-D Crust Structure for the Longmen Lithosphere and the Genesis of the Huge Wenchuan Earthquake,Sichuan Province,China(Journal of Chengdu University of Technology,ISSN1671-9727,CN51-1634/N,35(4),2008,p.357-365,8 illus.,39 refs.)Key words:deep-seated structures,large earthquakes,Longmenshan Fracture ZoneBased on a structural analysis of many seismic sounding profiles,there are two fault systems in Longmen collisional orogenic belt,Sichuan Province,China.They are both different obviously and correlative closely.One is shallow fault system composed mainly of brittle shear zones in surface crust,and the other is deep fault system composed mainly of crust-mantle ductile shear zones cutting Moho discontinuity.Based on the result of researching geological structure and seismic sounding profiles,

  3. Joint inversion of seismic traveltime and gravity data: A synthetic study using geologically realistic models from the Voisey's Bay deposit

    Carter-McAuslan, A.; Lelièvre, P. G.; Farquharson, C.


    Seismic methods provide high resolving potential for use in mineral exploration. Unfortunately, complicated hard-rock geology can make seismic data processing and interpretation difficult. It may help to overcome these difficulties by jointly inverting seismic tomography data with gravity data. We investigated the viability of deterministic minimum-structure style joint inversion of seismic traveltime and gravity data for the delineation of geological targets from the Voisey's Bay sulfide deposit in Labrador, Canada. These tests also assessed the potential of employing borehole gravity. A number of synthetic Earth models were created based on the geology of the Eastern Deeps zone of the Voisey's Bay deposit. These models were built on triangular (2D) and tetrahedral (3D) unstructured meshes, allowing for efficient generation of complicated, realistic geological structures. 2D models were based on conceptualized models of the Eastern Deeps. A detailed 3D model was built using information from extensive drilling. Single property and joint inversions were performed with seismic traveltimes and both ground-based and borehole gravity. There is a known relationship between seismic velocity and density for both silicate rocks and sulphide minerals for our study area; this lithological relationship was used to design an appropriate coupling strategy in the joint inversions. Joint inversions were able to successfully locate a buried high contrast target with a variety of survey designs. Experimentation with noise levels, mesh design, and various inversion parameters has lead to a better understanding of how to practically apply joint inversion of traveltimes and gravity data to this and similar exploration problems.

  4. Patterns and Determinants of Treatment Seeking among Previously Untreated Psychotic Patients in Aceh Province, Indonesia: A Qualitative Study

    Marthoenis Marthoenis


    Full Text Available Immediate treatment of first-episode psychosis is essential in order to achieve a positive outcome. However, Indonesian psychiatric patients often delay accessing health services, the reason for which is not yet fully understood. The current study aimed to understand patterns of treatment seeking and to reveal determinants of the delay in accessing psychiatric care among first-time user psychotic patients. Qualitative interviews were conducted with sixteen family members who accompanied the patients to a psychiatric hospital. Many families expressed beliefs that mental illness appertains to village sickness and not hospital sickness; therefore, they usually take the patients to traditional or religious healers before taking them to a health professional. They also identified various factors that potentially delay accessing psychiatric treatment: low literacy and beliefs about the cause of the illness, stigmatisation, the role of extended family, financial problems, and long distance to the psychiatric hospital. On the other hand, the family mentioned various factors related to timely help seeking, including being a well-educated family, living closer to health facilities, previous experience of successful psychotic therapy, and having more positive symptoms of psychosis. The findings call for mental health awareness campaigns in the community.

  5. Phase III randomized study of bendamustine compared with chlorambucil in previously untreated patients with chronic lymphocytic leukemia.

    Knauf, Wolfgang U; Lissichkov, Toshko; Aldaoud, Ali; Liberati, Anna; Loscertales, Javier; Herbrecht, Raoul; Juliusson, Gunnar; Postner, Gerhard; Gercheva, Liana; Goranov, Stefan; Becker, Martin; Fricke, Hans-Joerg; Huguet, Francoise; Del Giudice, Ilaria; Klein, Peter; Tremmel, Lothar; Merkle, Karlheinz; Montillo, Marco


    This randomized, open-label, parallel-group, multicenter study was designed to compare the efficacy and safety of bendamustine and chlorambucil in previously untreated patients with advanced (Binet stage B or C) chronic lymphocytic leukemia (CLL). Patients (chlorambucil 0.8 mg/kg (Broca's normal weight) orally on days 1 and 15; treatment cycles were repeated every 4 weeks for a maximum of six cycles. The response to treatment was assessed according to National Cancer Institute Working Group criteria, and the final determination of response was made by a blinded independent review committee. A total of 319 patients were randomly assigned (162 bendamustine, 157 chlorambucil). Complete or partial responses were achieved in 110 (68%) of 162 bendamustine-treated and 48 (31%) of 157 chlorambucil-treated patients (P chlorambucil (31% v 2%). Median progression-free survival was 21.6 months with bendamustine and 8.3 months with chlorambucil (P chlorambucil (median, 21.8 v 8.0 months). Hematologic National Cancer Institute Common Toxicity Criteria grade 3 to 4 adverse events were more common with bendamustine than with chlorambucil (occurring in 40% v 19% of patients). Severe infections (grade 3 to 4) occurred in 8% of bendamustine-treated patients and 3% of chlorambucil-treated patients. Bendamustine offers significantly greater efficacy than chlorambucil, and a manageable toxicity profile, when used as first-line therapy in patients with advanced CLL.

  6. Integrating Sonography Training Into Undergraduate Medical Education: A Study of the Previous Exposure of One Institution's Incoming Residents.

    Day, James; Davis, Joshua; Riesenberg, Lee Ann; Heil, Daniel; Berg, Katherine; Davis, Robyn; Berg, Dale


    Sonography is a crucial and versatile tool within the field of medicine. Recent advancements in technology have led to increased use of point-of-care sonography. We designed a survey to assess prior point-of-care sonography training among incoming interns at an academic teaching hospital. In 2012 and 2013, we surveyed incoming interns (n = 154 and 145, respectively) regarding point-of-care sonography training received during medical school. The survey questions included formal didactic sessions, bedside instruction, and the use of simulation technology. One-fourth (26.3% in 2012 and 23.4% in 2013) of responding interns reported having never done an ultrasound scan at the bedside. In 2012 and 2013, 55.0% and 55.6% of respondents reported never having done an ultrasound scan in a simulation center, respectively. Interns agreed that sonography education should be provided during medical school. On average, interns disagreed with the statement that sonography should be taught in residency only. There was no significant difference in the sex or general previous experience with sonography across both intern classes. Point-of-care sonography is inconsistently taught in medical school. The interns in our study also thought that sonography education should begin in medical school, and sonography should be taught by using simulation and at the bedside. © 2015 by the American Institute of Ultrasound in Medicine.

  7. Pilot Study of an Individualised Early Postpartum Intervention to Increase Physical Activity in Women with Previous Gestational Diabetes

    Harold David McIntyre


    Full Text Available Optimal strategies to prevent progression towards overt diabetes in women with recent gestational diabetes remain ill defined. We report a pilot study of a convenient, home based exercise program with telephone support, suited to the early post-partum period. Twenty eight women with recent gestational diabetes were enrolled at six weeks post-partum into a 12 week randomised controlled trial of Usual Care (n=13 versus Supported Care (individualised exercise program with regular telephone support; n=15. Baseline characteristics (Mean ± SD were: Age  33±4  years; Weight 80 ± 20 kg and Body Mass Index (BMI 30.0±9.7 kg/m2. The primary outcome, planned physical activity {Median (Range}, increased by 60 (0–540 mins/week in the SC group versus 0 (0–580 mins/week in the UC group (P=0.234. Walking was the predominant physical activity. Body weight, BMI, waist circumference, % body fat, fasting glucose and insulin did not change significantly over time in either group. This intervention designed to increase physical activity in post-partum women with previous gestational diabetes proved feasible. However, no measurable improvement in metabolic or biometric parameters was observed over a three month period.

  8. Risk factors and therapeutic coverage at 6 years in patients with previous myocardial infarction: the CASTUO study

    Félix-Redondo, Francisco Javier; Lozano Mera, Luis; Consuegra-Sánchez, Luciano; Giménez Sáez, Fernando; Garcipérez de Vargas, Francisco Javier; Castellano Vázquez, José María; Fernández-Bergés, Daniel


    Objectives To determine the degree of risk factor control, the clinical symptoms and the therapeutic management of patients with a history of previous myocardial infarction. Methods Cross-sectional study at 6 years of a first episode of acute myocardial infarction between 2000 and 2009, admitted at a hospital in the region of Extremadura (Spain). Of 2177 patients with this diagnosis, 1365 remained alive and therefore were included in the study. Results We conducted a person-to-person survey in 666 (48.8%) individuals and telephone survey in 437 (31.9%) individuals. The former are analysed. 130 were female (19.5%). The mean age was 67.4 years and the median time since the event was 5.8 (IQR 3.6–8.2) years. Active smokers made up 13.8%, low-density lipoprotein (LDL) cholesterol was ≥70 mg/dL: 82%, blood pressure ≥140/90 mm Hg (≥140/85 in diabetics): 49.8%, fasting glucose ≥126 mg/dL: 26%, heart rate 50–59 bpm: 60.7%, and obesity: 45.9%. Patients reported presenting angina comprised 22.4% and those with dyspnoea, 29.3%. Drug coverage was: 88.0% antiplatelet drugs, 86.5% statins, 75.6% β-blockers and 65.8% blockers of the renin-angiotensin system. Patients receiving all four types of drugs made up 41.9%, with only 3.0% having jointly controlled cholesterol, blood pressure, heart rate and glycaemia. Conclusions LDL cholesterol, heart rate and blood pressure were risk factors with less control. More than 1/5 of patients had angina and more than 1/4, dyspnoea. Risk factor control and the clinical condition were far from optimal, as was drug coverage, although to a lesser degree. PMID:27127637

  9. Structural and Seismic Stratigrapic study in the Center of the Magdalena Shelf in the Western Margin of Baja California Based on Seismic Reflection Data

    González-Escobar, Mario; Salazar-Cárdenas, Rosa M.; Munguía, Luis; Martín, Arturo; Suárez-Vidal, Francisco


    The Magdalena Shelf is a shallow, low-relief surface located along the Baja California Pacific margin. As part of a forearc basin, the shelf was a convergent margin setting before the oblique divergent plate boundary formed in the Gulf of California at 12 Ma. It is thought that since 12-8 Ma, this basin has been a transtensional or strike-slip basin. To constrain the geometry, structural characteristics and some stratigraphic relationships, an active-source, seismic-reflection study was carried out in the central part of the shelf. As a result, the analyzed data show faults, basins and unconformities. Two out of four observed basins are clearly controlled by the Santa Margarita and San Lázaro faults that dip ~40° NE; a third basin is controlled by the Tosco-Abreojos fault. These three basins are part of the deformation zone that is associated with the Tosco-Abreojos fault system. The Iray-Margarita basin, on the other hand, is a fourth basin located at the northeast sector of the study area. An additional feature observed is a stepover lying between the overlapping ends of the Santa Margarita and San Lázaro faults. Small faults oriented sub-parallel to the above major faults are present, mainly throughout the western sector of the study area. Some of those minor faults cut through the seafloor indicating recent tectonic activity. Santa Margarita, San Lázaro and Tosco-Abreojos are also the names given to half-grabens controlled by the active faults that have the same names. The first two basins are affected by many more small faults in comparison with what we see in the third basin. Tectonically, this means that those two basins are the more active in the area of study. In all four basins, the upper seismic sequence consists of sediments controlled by faults of Neogene age. We found that the Iray-Santa Margarita basin is the deepest of all four basins (beyond the resolution of the data, >5 km), and lack of minor faults there indicates that the basin is not

  10. Structural and Seismic Stratigrapic study in the Center of the Magdalena Shelf in the Western Margin of Baja California Based on Seismic Reflection Data

    González-Escobar, Mario; Salazar-Cárdenas, Rosa M.; Munguía, Luis; Martín, Arturo; Suárez-Vidal, Francisco


    The Magdalena Shelf is a shallow, low-relief surface located along the Baja California Pacific margin. As part of a forearc basin, the shelf was a convergent margin setting before the oblique divergent plate boundary formed in the Gulf of California at 12 Ma. It is thought that since 12-8 Ma, this basin has been a transtensional or strike-slip basin. To constrain the geometry, structural characteristics and some stratigraphic relationships, an active-source, seismic-reflection study was carried out in the central part of the shelf. As a result, the analyzed data show faults, basins and unconformities. Two out of four observed basins are clearly controlled by the Santa Margarita and San Lázaro faults that dip ~40° NE; a third basin is controlled by the Tosco-Abreojos fault. These three basins are part of the deformation zone that is associated with the Tosco-Abreojos fault system. The Iray-Margarita basin, on the other hand, is a fourth basin located at the northeast sector of the study area. An additional feature observed is a stepover lying between the overlapping ends of the Santa Margarita and San Lázaro faults. Small faults oriented sub-parallel to the above major faults are present, mainly throughout the western sector of the study area. Some of those minor faults cut through the seafloor indicating recent tectonic activity. Santa Margarita, San Lázaro and Tosco-Abreojos are also the names given to half-grabens controlled by the active faults that have the same names. The first two basins are affected by many more small faults in comparison with what we see in the third basin. Tectonically, this means that those two basins are the more active in the area of study. In all four basins, the upper seismic sequence consists of sediments controlled by faults of Neogene age. We found that the Iray-Santa Margarita basin is the deepest of all four basins (beyond the resolution of the data, >5 km), and lack of minor faults there indicates that the basin is not

  11. Seismic Swarms at Paricutin Volcano Area. Magmatic Intrusion or Tectonic Seismicity?

    Pinzon, J. I.; Nunez-Cornu, F. J.; Escudero, C. R.; Rowe, C. A.


    We relocate a seismic swarm with more than 700 earthquakes that took place between May and June 2006 in the Paricutin volcano area, Mexico inside of the Michoacan monogenetic volcanic field. This seismic swarm was recorded by the project "Mapping the Riviera Subduction Zone" (MARS), a temporary seismic network that was installed in the states of Jalisco, Colima and Michoacán between January 2006 and June 2007. Previously seismic swarms in the area were reported in the years of 1997, 1999 and 2000. For one that took place in the year of 1997 the Servicio Sismologico Nacional deployed a local network in the area, they conclude that the source of the seismicity was tectonic with depths between 18 and 12 km. The episodes of 1999 and 2000 were reported as similar to the 1997 swarm. A previous analysis of the 2006 swarm concludes that the depth of seismicity migrates from 9 to 5 km and was originated by a magmatic intrusion. We did a relocation of this swarm reading all the events and using Hypo71 and the P-wave velocity model used by the Jalisco Seismic and Acelerometric Network; a waveform analysis using cross-correlation method was also carried out. We obtained 15 earthquakes families with a correlation factor equal or greater than 0.79 and composed focal mechanism for each family. These families present a migration in depth beginning at 16 km and ended at 9 km. Our results agrees with a magmatic intrusion, but not so shallow as the previous study of the 2006 swarm.

  12. On the inverse seismic problem for horizontally layered media: Subsidiary study

    Cuer, Michel; Petit, Jean Louis

    The starting point of this work is the inversion of vertical seismic profiling (VSP) data. The usual processing of VSP data by inverse techniques is restricted to 1D propagation model. In this case, the parameters to identify are the acoustic impedance as function of travel time and the seismic source so that we have as unknowns two functions of one variable and as data a function of two variables, the time and the depth positions of geophones. The problem is thus largely overdetermined and an elementary mathematical analysis can be made. The source is modelled as a boundary condition at the top of the geophones zone. So this boundary condition replaces the true source function and the medium parameters above the geophones zone. The question asked by V. Richard from IFP was the "management" of this unknown source when 3D propagation effects are taken into account in horizontally layered medium where the propagation equations are parametrized by the k parameter of the Hankel transform. Now we think that the answer is that it is impossible to work round the fact that there are at least two unknown functions, the source and the medium parameters above the geophones zone. During this study, we have searched for some non local boundary conditions and this was the opportunity to obtain some results on exact transparent conditions for 3D propagation in 1D media (preliminary communication was made by Petit and Cuer (1994)) and on the discretization of such conditions in the acoustic case (preliminary communication was made by Cuer and Petit (1995)). This is the mathematical substance of this work in which the Poisson summation formula is used to prove the stability of a discrete non local boundary condition.

  13. Seismic studies of coal bed methane content in the west coal mining area of Qinshui Basin

    Zou Guangui⇑; Peng Suping; Yin Caiyun; Xu Yanyong; Chen Fengying; Liu Jinkai


    The coal bed methane content (CBMC) in the west mining area of Jincheng coalfield, southeastern Qinshui Basin, is studied based on seismic data and well-logs together with laboratory measurements. The results show that the Shuey approximation has better adaptability according to the Zoeppritz equation result;the designed fold number for an ordinary seismic data is sufficient for post-stack data but insufficient for pre-stack data regarding the signal to noise ratio (SNR). Therefore a larger grid analysis was created in order to improve the SNR. The velocity field created by logging is better than that created by stack velocity in both accuracy and effectiveness. A reasonable distribution of the amplitude versus offset (AVO) attributes can be facilitated by taking the AVO response from logging as a standard for calibrating the amplitude distribution. Some AVO attributes have a close relationship with CBMC. The worst attri-bute is polarization magnitude, for which the correlation coefficient is 0.308; and the best attribute is the polarization product from intercept, of which the correlation coefficient is ?0.8136. CBMC predicted by AVO attributes is better overall than that predicted by direct interpolation of CBMC; the validation error of the former is 14.47%, which is lower than that of the latter 23.30%. CBMC of this area ranges from 2.5 m3/t to 22 m3/t. Most CBMC in the syncline is over 10 m3/t, but it is below 10 m3/t in the anticline;on the whole, CBMC in the syncline is higher than that in anticline.

  14. Statistical Seismology and Induced Seismicity

    Tiampo, K. F.; González, P. J.; Kazemian, J.


    While seismicity triggered or induced by natural resources production such as mining or water impoundment in large dams has long been recognized, the recent increase in the unconventional production of oil and gas has been linked to rapid rise in seismicity in many places, including central North America (Ellsworth et al., 2012; Ellsworth, 2013). Worldwide, induced events of M~5 have occurred and, although rare, have resulted in both damage and public concern (Horton, 2012; Keranen et al., 2013). In addition, over the past twenty years, the increase in both number and coverage of seismic stations has resulted in an unprecedented ability to precisely record the magnitude and location of large numbers of small magnitude events. The increase in the number and type of seismic sequences available for detailed study has revealed differences in their statistics that previously difficult to quantify. For example, seismic swarms that produce significant numbers of foreshocks as well as aftershocks have been observed in different tectonic settings, including California, Iceland, and the East Pacific Rise (McGuire et al., 2005; Shearer, 2012; Kazemian et al., 2014). Similarly, smaller events have been observed prior to larger induced events in several occurrences from energy production. The field of statistical seismology has long focused on the question of triggering and the mechanisms responsible (Stein et al., 1992; Hill et al., 1993; Steacy et al., 2005; Parsons, 2005; Main et al., 2006). For example, in most cases the associated stress perturbations are much smaller than the earthquake stress drop, suggesting an inherent sensitivity to relatively small stress changes (Nalbant et al., 2005). Induced seismicity provides the opportunity to investigate triggering and, in particular, the differences between long- and short-range triggering. Here we investigate the statistics of induced seismicity sequences from around the world, including central North America and Spain, and

  15. Uncertainty in Seismic Capacity of Masonry Buildings

    Nicola Augenti


    Full Text Available Seismic assessment of masonry structures is plagued by both inherent randomness and model uncertainty. The former is referred to as aleatory uncertainty, the latter as epistemic uncertainty because it depends on the knowledge level. Pioneering studies on reinforced concrete buildings have revealed a significant influence of modeling parameters on seismic vulnerability. However, confidence in mechanical properties of existing masonry buildings is much lower than in the case of reinforcing steel and concrete. This paper is aimed at assessing whether and how uncertainty propagates from material properties to seismic capacity of an entire masonry structure. A typical two-story unreinforced masonry building is analyzed. Based on previous statistical characterization of mechanical properties of existing masonry types, the following random variables have been considered in this study: unit weight, uniaxial compressive strength, shear strength at zero confining stress, Young’s modulus, shear modulus, and available ductility in shear. Probability density functions were implemented to generate a significant number of realizations and static pushover analysis of the case-study building was performed for each vector of realizations, load combination and lateral load pattern. Analysis results show a large dispersion in displacement capacity and lower dispersion in spectral acceleration capacity. This can directly affect decision-making because both design and retrofit solutions depend on seismic capacity predictions. Therefore, engineering judgment should always be used when assessing structural safety of existing masonry constructions against design earthquakes, based on a series of seismic analyses under uncertain parameters.

  16. Persistence of cardiovascular risk factors in women with previous preeclampsia: a long-term follow-up study.

    Aykas, Fatma; Solak, Yalcin; Erden, Abdulsamet; Bulut, Kadir; Dogan, Selcuk; Sarli, Bahadr; Acmaz, Gokhan; Afsar, Baris; Siriopol, Dimitrie; Covic, Adrian; Sharma, Shailendra; Johnson, Richard J; Kanbay, Mehmet


    Preeclampsia is a cardiovascular (CV) disease risk factor, and lifestyle modifications are recommended. It was suggested that preeclampsia may increase the prevalence of various CV disease risk factors such as metabolic syndrome, hypertension, insulin resistance, microalbuminuria, and endothelial dysfunction, among others. Here, we investigate the role of serum uric acid in preeclampsia in the development of CV complications. This was an observational case-control study that compared women with history of preeclampsia (n = 25) with age-matched controls with uncomplicated pregnancies (n = 20) who were followed for at least 5 years. Measurements included clinical and ambulatory blood pressure monitoring, ultrasound-measured flow-mediated dilatation (FMD), microalbuminuria, carotid intima-media thickness (CIMT) and serum uric acid, as well as clinical and demographic features. Cardiovascular disease risk factors were compared in women with and without previous preeclampsia. At the time of index gestation, preeclamptic women had higher serum uric acid values (4.36 ± 0.61 vs 2.27 ± 0.38 mg/dL, P preeclampsia were more likely to have hypertension and had higher serum uric acid levels, higher microalbuminuria and CIMT levels, and lower FMD values than did the patients who did not have preeclampsia. The 2 groups were similar with regard to various ambulatory blood pressure parameters. Univariate associates of FMD were history of preeclampsia and the current hypertension status. Microalbuminuria correlated with gestational uric acid levels (coefficient of correlation of 0.40, P = 0.01 for FMD and coefficient of correlation of 0.37, P = 0.01 for CIMT, respectively). Preeclampsia might be a risk factor for the development of cardiovascular risk factors at least 5 years after index pregnancy. Serum uric acid and microalbuminuria may be mechanistic mediators of heightened risk, along with impaired endothelial function in preeclampsia.

  17. Sitagliptin added to previously taken antidiabetic agents on insulin resistance and lipid profile: a 2-year study evaluation.

    Derosa, Giuseppe; Ragonesi, Pietro Dario; Fogari, Elena; Cicero, Arrigo Francesco Giuseppe; Bianchi, Lucio; Bonaventura, Aldo; Romano, Davide; Maffioli, Pamela


    The aim of this study was to evaluate whether the positive effects of sitagliptin on glycemic control and insulin resistance were maintained also after 2 years of therapy and whether sitagliptin could be effective also in improving lipid profile. In this randomized, double-blind, placebo-controlled trial, 205 patients with type 2 diabetes in therapy with different antidiabetic drugs were randomized to add sitagliptin 100 mg once a day or placebo to their current therapy. We evaluated at the baseline and after 6, 12, 18, and 24 months the following parameters: body mass index, glycated hemoglobin (HbA1c ), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), fasting plasma insulin (FPI), homeostasis model assessment insulin resistance index (HOMA-IR), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (Tg). Sitagliptin, added to previously taken antidiabetic agents, proved to be effective in improving glycemic profile, reducing HbA1c by -17.5%, FPG by -12.7%, PPG by -20.5%. Regarding insulin resistance, sitagliptin decreased FPI by -8.3% and HOMA-IR by -20.0%, confirming that what have been already reported in short-term studies can be applied also after 2 years of treatment. Sitagliptin also reduced body weight by -4.3%. Our study also showed the positive effect of sitagliptin on lipid profile; in particular, sitagliptin decreased TC by -13.3%, LDL-C by -20.4%, and Tg by -32.3%, and also increased HDL-C by + 13.6%. Sitagliptin proved to be effective on glycemic profile and insulin resistance even after 2 years of therapy and to be effective in improving body weight and lipid profile. © 2012 The Authors Fundamental and Clinical Pharmacology © 2012 Société Française de Pharmacologie et de Thérapeutique.

  18. Study on the effect of the infill walls on the seismic performance of a reinforced concrete frame

    Zhang, Cuiqiang; Zhou, Ying; Zhou, Deyuan; Lu, Xilin


    Motivated by the seismic damage observed to reinforced concrete (RC) frame structures during the Wenchuan earthquake, the effect of infill walls on the seismic performance of a RC frame is studied in this paper. Infill walls, especially those made of masonry, offer some amount of stiffness and strength. Therefore, the effect of infill walls should be considered during the design of RC frames. In this study, an analysis of the recorded ground motion in the Wenchuan earthquake is performed. Then, a numerical model is developed to simulate the infill walls. Finally, nonlinear dynamic analysis is carried out on a RC frame with and without infill walls, respectively, by using CANNY software. Through a comparative analysis, the following conclusions can be drawn. The failure mode of the frame with infill walls is in accordance with the seismic damage failure pattern, which is strong beam and weak column mode. This indicates that the infill walls change the failure pattern of the frame, and it is necessary to consider them in the seismic design of the RC frame. The numerical model presented in this paper can effectively simulate the effect of infill walls on the RC frame.

  19. Effect of geological medium on seismic signals from underground nuclear explosion events – A case study for Baneberry site

    R K Singh; S K Sikka; Anil Kakodkar


    Seismic signals due to any underground nuclear explosion events are known to be influenced by the local geology of the test site and the yield level. In this paper, transient three-dimensional finite element code SHOCK-3D developed for the simulation of underground nuclear explosion events has been used to obtain synthetic acceleration signals for Baneberry site (Nevada) single and composite rock media. At this site an underground nuclear test of 10 kT conducted on 18th December 1970 at source depth of 278 m resulted into venting as reported by Terhune et al with 2D simulation results and later by us through 3D simulation in Ranjan et al. First, the reasons of the venting for this event are summarized. After the successful validation of the 3D numerical model for Baneberry site rock media, parametric studies are carried out for 1 and 8 kT yields at 100 m depth (Scaled Depths of Burst SDOB ∼ 100 and 50 m/kT1/3, respectively) for homogeneous and composite Paleozoic and Tuff media of Baneberry site. It is demonstrated that the near source local geological formations and associated nonlinear effects significantly influence the seismic signals. With this study the seismic decoupling of the source by an order of magnitude has been illustrated. Finally, it is concluded that the seismic signals alone, in the absence of in-depth information of the local geology of the specific test site, are not appropriate measures of the source strength.

  20. Study on Anti-seismic Strengthening of the Ancient Stone Archway

    Zhang Ding


    Full Text Available Chinese ancient stone archways are in flat structure. And joints of their members are of half tenons and mortises. Under the influence of the earthquake, the resisting ability of archway’s uneven sides is relatively poor and the relevant members have little reliable joints. This paper is to analyze seismic strengthening feasibility of Tiantai mountain stone archway which is damaged from the earthquake and to research on the aspects of the loading mode, structure layout and soundness. On the premise of guaranteeing the authenticity and beauty, we use earthquake damaging mechanism of stone archways and the modern anti-seismic structure designing theory and modern building materials. We also follow the way of the modern construction technology and ancient construction and strengthen the anti-seismic way of the resisting ability of Tiantai mountain stone archway’s uneven sides and joints of tenons and mortises. The best anti-seismic strengthening schemes are put forward as well.

  1. More than meets the eye---A study in seismic visualization

    Lynch, Steven

    This thesis is primarily concerned with examining the properties of SeisScape displays, which render seismic data as a three-dimensional surface. SeisScape displays are fundamentally different from conventional seismic displays in that they fully engage the visual system and produce sensations of perception. These perceptions are the goal of scientific visualization. Visualization itself is placed into context with respect to seismic data by discussing how the display acts as a filter upon seismic resolution. There are two levels of seismic resolution; absolute resolution, which is a product of spatial and temporal resolution; and apparent resolution, which is a product of the display. It is established that the apparent resolution of conventional displays is significantly lower than the absolute resolution of the data. The primate visual system is the second, immutable, stage of the seismic display filter. It is not, however, a general purpose tool. To learn how to use it appropriately, the evolution and properties of the primate visual system are discussed in the context of determining how primates establish their perceptions of form and color. Two terms that describe the structure of a seismic section are introduced. The first is macrostructure, which is the collection of strong amplitude events that are visible on any seismic section. The second is the microstructure, which is the collection of weak amplitude events that are often only observed as perturbations upon the macrostructure. Several techniques for tessellating the seismic surface are developed. Examples are presented to illustrate the effect that tessellation has on the ability to perceive both macrostructure and microstructure. Various techniques are developed to calculate the reflectance of the seismic surface and examples show how reflectance is primarily responsible for our ability to perceive microstructure. The use of color on seismic data is examined from the perspective of the evolution of

  2. Central Arctic atmospheric summer conditions during the Arctic Summer Cloud Ocean Study (ASCOS: contrasting to previous expeditions

    M. Tjernström


    Full Text Available Understanding the rapidly changing climate in the Arctic is limited by a lack of understanding of underlying strong feedback mechanisms that are specific to the Arctic. Progress in this field can only be obtained by process-level observations; this is the motivation for intensive ice-breaker-based campaigns such as that described in this paper: the Arctic Summer Cloud-Ocean Study (ASCOS. However, detailed field observations also have to be put in the context of the larger-scale meteorology, and short field campaigns have to be analysed within the context of the underlying climate state and temporal anomalies from this.

    To aid in the analysis of other parameters or processes observed during this campaign, this paper provides an overview of the synoptic-scale meteorology and its climatic anomaly during the ASCOS field deployment. It also provides a statistical analysis of key features during the campaign, such as some key meteorological variables, the vertical structure of the lower troposphere and clouds, and energy fluxes at the surface. In order to assess the representativity of the ASCOS results, we also compare these features to similar observations obtained during three earlier summer experiments in the Arctic Ocean, the AOE-96, SHEBA and AOE-2001 expeditions.

    We find that these expeditions share many key features of the summertime lower troposphere. Taking ASCOS and the previous expeditions together, a common picture emerges with a large amount of low-level cloud in a well-mixed shallow boundary layer, capped by a weak to moderately strong inversion where moisture, and sometimes also cloud top, penetrate into the lower parts of the inversion. Much of the boundary-layer mixing is due to cloud-top cooling and subsequent buoyant overturning of the cloud. The cloud layer may, or may not, be connected with surface processes depending on the depths of the cloud and surface-based boundary layers and on the relative strengths of

  3. Seismic Hazard Analysis in EL Paso/juarez Area from Study of Young Fault Scarps

    ashenfelter, K. R.


    The El Paso-Juarez metropolitan area contains a known record of active faulting, but also has one of the most poorly known paleoseismic records. The scarcity of data means that nearly 2 million people are exposed to a seismic hazard with little known on the actual risk. Active faults are known along the eastern side of the Franklin Mountains as well as young ruptures within the Hueco Bolson in East El Paso, yet the only fault with paleoseismic studies is the East Franklin's fault. Recent population increases in the El Paso region have led to a construction boom in east El Paso, and many of these construction sites cross known Quaternary fault ruptures. This research project contains two potential components: 1) An exploratory component: students can use existing fault maps and high resolution aerial photography to seek out sites where active construction sites might be unearthing exposures of young fault ruptures. The study is exploratory, and involves carefully mapping using field GIS systems to document areas for potential study, map possible faults, etc. 2) An active fault study in an urbanized environment: The east Franklins fault is a known active fault. The scarp is exposed near trans-mountain road, and along some side streets in NE El Paso. Potential studies include careful mapping of fault scarp topographic profiles, and mapping surface traces.

  4. Site study plan for EDBH (Engineering Design Boreholes) seismic surveys, Deaf Smith County site, Texas: Revision 1

    Hume, H.


    This site study plan describes seismic reflection surveys to run north-south and east-west across the Deaf Smith County site, and intersecting near the Engineering Design Boreholes (EDBH). Both conventional and shallow high-resolution surveys will be run. The field program has been designed to acquire subsurface geologic and stratigraphic data to address information/data needs resulting from Federal and State regulations and Repository program requirements. The data acquired by the conventional surveys will be common-depth- point, seismic reflection data optimized for reflection events that indicate geologic structure near the repository horizon. The data will also resolve the basement structure and shallow reflection events up to about the top of the evaporite sequence. Field acquisition includes a testing phase to check/select parameters and a production phase. The field data will be subjected immediately to conventional data processing and interpretation to determine if there are any anamolous structural for stratigraphic conditions that could affect the choice of the EDBH sites. After the EDBH's have been drilled and logged, including vertical seismic profiling, the data will be reprocessed and reinterpreted for detailed structural and stratigraphic information to guide shaft development. The shallow high-resulition seismic reflection lines will be run along the same alignments, but the lines will be shorter and limited to immediate vicinity of the EDBH sites. These lines are planned to detect faults or thick channel sands that may be present at the EDBH sites. 23 refs. , 7 figs., 5 tabs.

  5. Co-seismic landslide topographic analysis based on multi-temporal DEM-A case study of the Wenchuan earthquake.

    Ren, Zhikun; Zhang, Zhuqi; Dai, Fuchu; Yin, Jinhui; Zhang, Huiping


    Hillslope instability has been thought to be one of the most important factors for landslide susceptibility. In this study, we apply geomorphic analysis using multi-temporal DEM data and shake intensity analysis to evaluate the topographic characteristics of the landslide areas. There are many geomorphologic analysis methods such as roughness, slope aspect, which are also as useful as slope analysis. The analyses indicate that most of the co-seismic landslides occurred in regions with roughness, hillslope and slope aspect of >1.2, >30, and between 90 and 270, respectively. However, the intersection regions from the above three methods are more accurate than that derived by applying single topographic analysis method. The ground motion data indicates that the co-seismic landslides mainly occurred on the hanging wall side of Longmen Shan Thrust Belt within the up-down and horizontal peak ground acceleration (PGA) contour of 150 PGA and 200 gal, respectively. The comparisons of pre- and post-earthquake DEM data indicate that the medium roughness and slope increased, the roughest and steepest regions decreased after the Wenchuan earthquake. However, slope aspects did not even change. Our results indicate that co-seismic landslides mainly occurred at specific regions of high roughness, southward and steep sloping areas under strong ground motion. Co-seismic landslides significantly modified the local topography, especially the hillslope and roughness. The roughest relief and steepest slope are significantly smoothed; however, the medium relief and slope become rougher and steeper, respectively.

  6. A study on the seismic behavior of a retrofitted building based on nonlinear static and dynamic analyses

    Esra Mete Güneyisi; Gülay Altay


    This study describes the seismic performance of an existing five storey reinforced concrete building which represents the typical properties of low-rise non-ductile buildings in Turkey. The effectiveness of shear walls and the steel bracings in retrofitting the building was examined through nonlinear static and dynamic analyses. By using the nonlinear static analysis, retrofitted buildings seismic performances under lateral seismic load were compared with each other.Moreover, the performance points and response levels of the existing and retrofitting cases were determined by way of the capacity-spectrum method described in ATC-40 (1996). For the nonlinear dynamic analysis the records were selected to represent wide ranges of duration and frequency content. Considering the change in the stiffness and the energy dissipation capacities, the performance of the existing and retrofitted buildings were evaluated in terms of story drifts and damage states.It was found that each earthquake record exhibited its own peculiarities, dictated by frequency content, duration, sequence of peaks and their amplitude. The seismic performance of retrofitted buildings resulted in lower displacements and higher energy dissipation capacity depending mainly on the properties of the ground motions and the retrofitting strategies. Moreover,severe structural damage (irreparable or collapse) was observed for the existing building. However, buildings with retrofit alternatives exhibited lower damage levels changing from no damage to irreparable damage states.

  7. Seismic Study of the Velocity Structure and Earthquake FocalMechanisms beneath the Krafla Central Volcano, NE Iceland

    Martens, H. R.; Schuler, J.; Greenfield, T. S.; White, R. S.; Roecker, S. W.; Brandsdottir, B.; Stock, J. M.; Tarasewicz, J.; Pugh, D. J.


    We investigated the seismic velocity structure of the Krafla central volcano, NE Iceland, and its shallow geothermal fields. In our 3D tomographic inversions, we used passive seismic data recorded between 2009-2012 from a temporary local network as well as active seismic legacy data to constrain the velocity models. We find high P-wave velocities (Vp) underneath regions of elevated topographic relief as well as two low-Vp anomalies that coincide spatially with two attenuating bodies outlined from S-wave shadows during the Krafla rifting episode of 1974-1985. Within the Krafla geothermal reservoir, which is developed for energy production, we imaged a shallow low-Vp/Vs zone overlying a deeper high-Vp/Vs zone and interpreted them as steam- and brine-bearing formations, respectively. Previously undertaken borehole measurements support our findings. A prominent low-Vp/Vs anomaly underlies these zones at rock depths greater than 1.5 km, where a super-heated zone within felsic overlies rhyolitic within the geothermal melt. Calculations systems show that of the most earthquake focal events are mechanisms consistent double-couple source models with only a few clear non-shear source models.

  8. Study on the Seismic Active Earth Pressure by Variational Limit Equilibrium Method

    Jiangong Chen


    Full Text Available In the framework of limit equilibrium theory, the isoperimetric model of functional extremum regarding the seismic active earth pressure is deduced according to the variational method. On this basis, Lagrange multipliers are introduced to convert the problem of seismic active earth pressure into the problem on the functional extremum of two undetermined function arguments. Based on the necessary conditions required for the existence of functional extremum, the function of the slip surface and the normal stress distribution on the slip surface is obtained, and the functional extremum problem is further converted into a function optimization problem with two undetermined Lagrange multipliers. The calculated results show that the slip surface is a plane and the seismic active earth pressure is minimal when the action point is at the lower limit position. As the action point moves upward, the slip surface becomes a logarithmic spiral and the corresponding value of seismic active earth pressure increases in a nonlinear manner. And the seismic active earth pressure is maximal at the upper limit position. The interval estimation constructed by the minimum and maximum values of seismic active earth pressure can provide a reference for the aseismic design of gravity retaining walls.

  9. A study on the Gaussianity and stationarity of the random noise in the seismic exploration

    Wang, Dongmei; Li, Yue; Nie, Pengfei


    Seismic exploration is an important means of the resource exploration. With the increasing of the demand for oil, gas and mineral resources, the resources which are easy to explore are reducing. At the same time, the high signal to noise ratio and the high quality seismic data is required with the continuous improvement of the accuracy of seismic exploration. The characteristics of complex noise in the seismic record are needed to be analyzed in detail in order to suppress the random noise and achieve the preserved amplitude processing as much as possible. The paper researches the Gaussianity and stationarity of the random noise in the seismic exploration of land area in China. The research areas are plain with sandstone structure. First, a theoretical model verifies the effectiveness that the Shapiro-Wilk test method is used in Gaussian statistical research, and the combination of surrogate data and time-frequency analysis tests stationarity. Then, there are 98.54% of the record channels which refuse the assumption of the Gaussian noise, and 25.6% of the record channels which don't meet the stationarity noise analysis by the above method in the research area through the statistical analysis of the seismic noise. Finally, we discuss the causes of non-Gaussianity and quasi-stationarity, and analyze the application of judging the stationarity in the denoising processing.

  10. A seismic diffraction extraction method for the study of discontinuous geologies using a regularisation algorithm

    Yu, Caixia; Wang, Yanfei; Zhao, Jingtao


    Seismic diffractions play a vital role in identifying discontinuous geological structures, such as tiny faults and cavities which are important because of their close relationship with the reservoir properties of oil and gas. In this paper, we focus on an extraction method for separation of seismic diffractions. The energy of reflection is usually much stronger than that of the diffraction, thus, removing reflection becomes a key problem for diffraction applications. In order to extract seismic diffractions accurately and stably, we propose an optimised regularisation method based on the local plane-wave equation. By considering two constraints arising from the Sobolev penalty function and the difference operator, we build a stable minimisation model for determining seismic slopes. In computation, an iterative method based on projection onto a convex set for solving the nonlinear minimisation is developed, which can provide fast and accurate solutions. Subtracting the predicted reflections from the seismic image, we can extract the seismic diffractions. Numerical experiments illustrate the effectiveness of the diffraction extraction method in separating tiny faults, scatterers and cavities. Finally, a carbonate reservoir field example is provided to demonstrate the high-resolution capability of the method in revealing small-scale discontinuous geological features.

  11. Relationship between the seismic scale of the 2011 northeast Japan earthquake and the incidence of acute myocardial infarction: A population-based study.

    Tanaka, Fumitaka; Makita, Shinji; Ito, Tomonori; Onoda, Toshiyuki; Sakata, Kiyomi; Nakamura, Motoyuki


    Previous studies have reported a relationship between large earthquakes and acute coronary events, but have yielded conflicting results. On March 11, 2011, a massive magnitude 9.0 earthquake hit the northeastern coast of Japan and generated repeated aftershocks. The aim of this study is to clarify the influence of this earthquake on the risk of acute myocardial infarction (AMI) including sudden cardiac death based on the data from a population-based analysis. The study subjects were residents in the northeast of Iwate prefecture, Japan. Cases corresponding to the definition of AMI according to the criteria of the World Health Organization MONICA project were registered from 4 weeks before to 8 weeks after the disaster and in the corresponding periods in 2009 and 2010. The relative risk of AMI was 2.03 (95% CI 1.55-2.66) for the 4-week period after the disaster compared with the corresponding periods in the preceding years. The number of events peaked within the first week after the earthquake decreased to levels seen in the preceding years and then increased again after high-magnitude aftershocks. The incidence of AMI was positively correlated with the seismic scale of the earthquake (r = 0.75, P earthquake varies depending on the seismic scale of the initial shock and each aftershock. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Detailed Study of Seismic Wave Attenuation in Carbonate Rocks: Application on Abu Dhabi Oil Fields

    Bouchaala, F.; Ali, M. Y.; Matsushima, J.


    Seismic wave attenuation is a promising attribute for the petroleum exploration, thanks to its high sensitivity to physical properties of subsurface. It can be used to enhance the seismic imaging and improve the geophysical interpretation which is crucial for reservoir characterization. However getting an accurate attenuation profile is not an easy task, this is due to complex mechanism of this parameter, although that many studies were carried out to understand it. The degree of difficulty increases for the media composed of carbonate rocks, known to be highly heterogeneous and with complex lithology. That is why few attenuation studies were done successfully in carbonate rocks. The main objectives of this study are, Getting an accurate and high resolution attenuation profiles from several oil fields. The resolution is very important target for us, because many reservoirs in Abu Dhabi oil fields are tight.Separation between different modes of wave attenuation (scattering and intrinsic attenuations).Correlation between the attenuation profiles and other logs (Porosity, resistivity, oil saturation…), in order to establish a relationship which can be used to detect the reservoir properties from the attenuation profiles.Comparison of attenuation estimated from VSP and sonic waveforms. Provide spatial distribution of attenuation in Abu Dhabi oil fields.To reach these objectives we implemented a robust processing flow and new methodology to estimate the attenuation from the downgoing waves of the compressional VSP data and waveforms acquired from several wells drilled in Abu Dhabi. The subsurface geology of this area is primarily composed of carbonate rocks and it is known to be highly fractured which complicates more the situation, then we separated successfully the intrinsic attenuation from the scattering. The results show that the scattering is significant and cannot be ignored. We found also a very interesting correlation between the attenuation profiles and the

  13. Discussion on further studies to measure and evaluate fitness and motor performance for preschool children; summary and previous studies in Japan and future consideratin

    Murase, Tomohiko; Demura, Shinichi


    This article discusses and summarizes previous studies dealing with fitness and motor performance in preschool children from the viewpoint of measurement and evaluation, and determines topics for further studies. The studies reviewed in this article were mainly published in the “Japan Journal of Physical Education, Health and Sport Sciences” (edited by the Japan Society of Physical Education, Health and Sport Sciences), and the “Japanese Journal of Physical Fitness and Sports Medicine” (edite...

  14. Development of a shelf margin delta due to uplift of Munkagrunnur Ridge at the margin of Faroe-Shetland Basin: a seismic sequence stratigraphic study

    Òlavsdóttir, Jana; Boldreel, Lars Ole; Andersen, Moretn S


    During the last decade several 3D digital reflection seismic datasets have been acquired in the Faroese sector of the Faroe-Shetland Basin which allow detailed seismic interpretation and mapping of parts of the area. This study presents mapping and seismic sequence stratigraphic interpretation...... of parts of a c. 450 m thick, mid-Eocene delta extending over some 3500 km(2) in the Faroe-Shetland Basin. The delta built out into the basin from the Munkagrunnur Ridge and has been divided into nine seismic units. Isochore maps of these seismic units reveal a NW-SE depositional maximum trend, parallel...... curve indicates that the Faroe-Shetland Basin was characterized by almost continuous relative sea level rise in the mid Eocene. Multiple stages of uplift of the Munkagrunnur Ridge during the mid-Eocene are considered to be the most likely explanation for the multiple cycles of sea level change inferred...

  15. Superelastic SMA Belleville washers for seismic resisting applications: experimental study and modelling strategy

    Fang, Cheng; Zhou, Xiaoyi; Israel Osofero, Adelaja; Shu, Zhan; Corradi, Marco


    This study sheds considerable light on the potential of superelastic shape memory alloy Belleville washers for innovative seismic resisting applications. A series of experimental studies were conducted on washers with different stack combinations under varying temperatures and loading scenarios. The washers showed satisfactory self-centring and energy dissipation capacities at room temperature, although slight degradations of the hysteretic responses accompanied by residual deformations were induced. The hysteretic loops became stable after a few number of cycles, indicating good repeatability. The washers also showed good flexibility in terms of load resistance and deformation, which could be easily varied via changes in the stack combination. Compromised self-centring responses were observed at temperatures below 0 °C or above 40 °C, and a numerical study, validated by the experimental results, was adopted to further investigate the deformation mechanism of the washers. A further phenomenological model, taking account of the degradation effects under varied temperatures, was developed to enable effective and accurate simulation of devices incorporating the washers. Good agreements were observed between the test and simulation results, and the model was shown to have good numerical robustness for wide engineering applications.

  16. Comparative seismic and petrographic crustal study between the Western and Eastern Sierras Pampeanas region (31°S

    P. Alvarado


    Full Text Available The ancient Sierras Pampeanas in the central west part of Argentina are a seismically active region in the back-arc of the Andes. Their crystalline basement cored uplifts extend up to 800 km east of the oceanic trench over the flat subduction segment of the Nazca plate. Approximately 40 felt crustal earthquakes, are reported per year for this region. Historic and modern seismicity indicates that the Western Sierras Pampeanas (WSP have more crustal earthquakes of greater-size than the Eastern Sierras Pampeanas (ESP. Remarkable changes in composition and structure also characterize the WSP and ESP basements. We have quantitatively compared both regions using seismological constrains. A recent regional study of moderate earthquakes shows reverse and thrust focal mechanisms occurring at depths down to 25 km in the WSP. In contrast, the ESP have reverse and strike-slip focal mechanisms of shallower depths (< 10 km. A seismic velocity structure of Vp 6.4 km/s, Vp/Vs ~1.80, and thickness 50 km, best represents the WSP crust. The ESP crust is characterized by Vp 6.0 km/s, Vp/Vs < 1.70, and thickness 30 km. These seismological determinations correlate with the interpretation of a different origin for the western and eastern terranes. The WSP show seismic properties indicative of a more mafic-ultramafic thick crust consistent with an oceanic island-arc and back-arc formation. The ESP show crustal seismic properties consistent with a higher silica content and with a formation by the collision of a continental terrane.

  17. Observational Studies of Earthquake Preparation and Generation to Mitigate Seismic Risks in Mines

    Durrheim, R. J.; Ogasawara, H.; Nakatani, M.; Milev, A.; Cichowicz, A.; Kawakata, H.; Yabe, Y.; Murakami, O.; Naoi, M. M.; Moriya, H.; Satoh, T.


    We provide a status report on a 5-year project to monitor in-situ fault instability and strong motion in South African gold mines. The project has two main aims: (1) To learn more about earthquake preparation and generation mechanisms by deploying dense arrays of high-sensitivity sensors within rock volumes where mining is likely to induce significant seismic activity. (2) To upgrade the South African national surface seismic network in the mining districts. This knowledge will contribute to efforts to upgrade schemes of seismic hazard assessment and to limit and mitigate the seismic risks in deep mines. As of 31 July 2011, 46 boreholes totalling 1.9 km in length had been drilled at project sites at Ezulwini, Moab-Khotsong and Driefontein gold mines. Several dozen more holes are still to be drilled. Acoustic emission sensors, strain- and tiltmeters, and controlled seismic sources are being installed to monitor the deformation of the rock mass, the accumulation of damage during the preparation phase, and changes in dynamic stress as the rupture front propagates. These data will be integrated with measurements of stope closure, stope strong motion, seismic data recorded by the mine-wide network, and stress modelling. Preliminary results will be reported at AGU meeting. The project is endorsed by the Japan Science and Technology Agency (JST), Japan International Cooperation Agency (JICA) and the South African government. It is funded by the JST-JICA program for Science and Technology Research Partnership for Sustainable development (SATREPS, the Council for Scientific and Industrial Research (CSIR), the Council for Geoscience, the University of the Witwatersrand and the Department of Science and Technology. The contributions of Seismogen CC, OHMS Ltd, AnglogoldAshanti Rock Engineering Applied Research Group, First Uranium, the Gold Fields Seismic Department and the Institute of Mine Seismology are gratefully acknowledged.

  18. Seismic Catalogue and Seismic Network in Haiti

    Belizaire, D.; Benito, B.; Carreño, E.; Meneses, C.; Huerfano, V.; Polanco, E.; McCormack, D.


    The destructive earthquake occurred on January 10, 2010 in Haiti, highlighted the lack of preparedness of the country to address seismic phenomena. At the moment of the earthquake, there was no seismic network operating in the country, and only a partial control of the past seismicity was possible, due to the absence of a national catalogue. After the 2010 earthquake, some advances began towards the installation of a national network and the elaboration of a seismic catalogue providing the necessary input for seismic Hazard Studies. This paper presents the state of the works carried out covering both aspects. First, a seismic catalogue has been built, compiling data of historical and instrumental events occurred in the Hispaniola Island and surroundings, in the frame of the SISMO-HAITI project, supported by the Technical University of Madrid (UPM) and Developed in cooperation with the Observatoire National de l'Environnement et de la Vulnérabilité of Haiti (ONEV). Data from different agencies all over the world were gathered, being relevant the role of the Dominican Republic and Puerto Rico seismological services which provides local data of their national networks. Almost 30000 events recorded in the area from 1551 till 2011 were compiled in a first catalogue, among them 7700 events with Mw ranges between 4.0 and 8.3. Since different magnitude scale were given by the different agencies (Ms, mb, MD, ML), this first catalogue was affected by important heterogeneity in the size parameter. Then it was homogenized to moment magnitude Mw using the empirical equations developed by Bonzoni et al (2011) for the eastern Caribbean. At present, this is the most exhaustive catalogue of the country, although it is difficult to assess its degree of completeness. Regarding the seismic network, 3 stations were installed just after the 2010 earthquake by the Canadian Government. The data were sent by telemetry thought the Canadian System CARINA. In 2012, the Spanish IGN together

  19. Nonlinear Seismic Analysis of Morrow Point Dam: A Study for the United States Bureau of Reclamation

    Noble, C R; Solberg, J


    This research and development project was sponsored by the United States Bureau of Reclamation (USBR), who are best known for the dams, power plants, and canals it constructed in the 17 western states. The mission statement of the USBR's Dam Safety Office, located in Denver, Colorado, is ''to ensure Reclamation dams do not present unacceptable risk to people, property, and the environment.'' The Dam Safety Office does this by quickly identifying the dams which pose an increased threat to the public, and quickly completing the related analyses in order to make decisions that will safeguard the public and associated resources. The research study described in this report constitutes one element of USBR's research and development work to advance their computational and analysis capabilities for studying the response of dams to strong earthquake motions. This project focused on the seismic response of Morrow Point Dam, which is located 263 km southwest of Denver, Colorado.

  20. A Study on the Compatibility of 3-D Seismic Velocity Structures with Gravity Data of Taiwan

    Horng-Yuan Yen and Hsien-Hsiang Hsieh


    Full Text Available The Bouguer anomaly of Taiwan has been revised in this study based on more accurate terrain data provided by the Taiwanese Digital Terrain Model compiled by the Taiwan Forestry Bureau. Three seismic velocity models, those determined by Rau and Wu (1995, Kim et al. (2005, and Wu et al. (2007 respectively, were selected for our study. We converted their velocity models to density models using the relationship between P-wave velocity and rock density proposed by Ludwig et al. (1970 and Barton (1986, and then calculated their corresponding gravity anomalies. According to the correlation coefficient between the Bouguer anomalies calculated from the velocity models and the revised Bouguer anomalies, the Kim et al. model was more compatible with gravity data than the other two velocity models. The differences between the revised gravity anomaly and the calculated gravity anomalies trend toward positive values at elevations higher than 2000 m. This indicates that the velocities at the shallower depths beneath the mountainous area of the three models are overdetermined, i.e., higher than the real velocities. This ratiocination implies that the crustal thickness beneath the Central Range is less than 55 km which was obtained from the velocity models.

  1. Randomized, multicenter, phase 2 study (EVOLUTION) of combinations of bortezomib, dexamethasone, cyclophosphamide, and lenalidomide in previously untreated multiple myeloma.

    Kumar, Shaji; Flinn, Ian; Richardson, Paul G; Hari, Parameswaran; Callander, Natalie; Noga, Stephen J; Stewart, A Keith; Turturro, Francesco; Rifkin, Robert; Wolf, Jeffrey; Estevam, Jose; Mulligan, George; Shi, Hongliang; Webb, Iain J; Rajkumar, S Vincent


    Combinations of bortezomib (V) and dexamethasone (D) with either lenalidomide (R) or cyclophosphamide (C) have shown significant efficacy. This randomized phase 2 trial evaluated VDC, VDR, and VDCR in previously untreated multiple myeloma (MM). Patients received V 1.3 mg/m2 (days 1, 4, 8, 11) and D 40 mg (days 1, 8, 15), with either C 500 mg/m2 (days 1, 8) and R 15 mg (days 1-14; VDCR), R 25 mg (days 1-14; VDR), C 500 mg/m2 (days 1, 8; VDC) or C 500 mg/m2 (days 1, 8, 15; VDC-mod) in 3-week cycles (maximum 8 cycles), followed by maintenance with V 1.3 mg/m2 (days 1, 8, 15, 22) for four 6-week cycles (all arms)≥very good partial response was seen in 58%, 51%, 41%, and 53% (complete response rate of 25%, 24%, 22%, and 47%) of patients (VDCR, VDR, VCD, and VCD-mod, respectively); the corresponding 1-year progression-free survival was 86%, 83%, 93%, and 100%, respectively. Common adverse events included hematologic toxicities, peripheral neuropathy, fatigue, and gastrointestinal disturbances. All regimens were highly active and well tolerated in previously untreated MM, and, based on this trial, VDR and VCD-mod are preferred for clinical practice and further comparative testing. No substantial advantage was noted with VDCR over the 3-drug combinations. This trial is registered at (NCT00507442).

  2. Issues Related to Seismic Activity Induced by the Injection of CO2 in Deep Saline Aquifers

    Sminchak, Joel [Battelle Memorial Institute, Columbus, OH (US); Gupta, Neeraj [Battelle Memorial Institute, Columbus, OH (US); Byrer, Charles [National Energy Technology Laboratory, Pittsburgh, PA, and Morgantown, WV (US); Bergman, Perry [National Energy Technology Laboratory, Pittsburgh, PA, and Morgantown, WV (US)


    Case studies, theory, regulation, and special considerations regarding the disposal of carbon dioxide (CO2) into deep saline aquifers were investigated to assess the potential for induced seismic activity. Formations capable of accepting large volumes of CO2 make deep well injection of CO2 an attractive option. While seismic implications must be considered for injection facilities, induced seismic activity may be prevented through proper siting, installation, operation, and monitoring. Instances of induced seismic activity have been documented at hazardous waste disposal wells, oil fields, and other sites. Induced seismic activity usually occurs along previously faulted rocks and may be investigated by analyzing the stress conditions at depth. Seismic events are unlikely to occur due to injection in porous rocks unless very high injection pressures cause hydraulic fracturing. Injection wells in the United States are regulated through the Underground Injection Control (UIC) program. UIC guidance requires an injection facility to perform extensive characterization, testing, and monitoring. Special considerations related to the properties of CO2 may have seismic ramifications to a deep well injection facility. Supercritical CO2 liquid is less dense than water and may cause density-driven stress conditions at depth or interact with formation water and rocks, causing a reduction in permeability and pressure buildup leading to seismic activity. Structural compatibility, historical seismic activity, cases of seismic activity triggered by deep well injection, and formation capacity were considered in evaluating the regional seismic suitability in the United States. Regions in the central, midwestern, and southeastern United States appear best suited for deep well injection. In Ohio, substantial deep well injection at a waste disposal facility has not caused seismic events in a seismically active area. Current

  3. Reproducibility in Seismic Imaging

    González-Verdejo O.


    Full Text Available Within the field of exploration seismology, there is interest at national level of integrating reproducibility in applied, educational and research activities related to seismic processing and imaging. This reproducibility implies the description and organization of the elements involved in numerical experiments. Thus, a researcher, teacher or student can study, verify, repeat, and modify them independently. In this work, we document and adapt reproducibility in seismic processing and imaging to spread this concept and its benefits, and to encourage the use of open source software in this area within our academic and professional environment. We present an enhanced seismic imaging example, of interest in both academic and professional environments, using Mexican seismic data. As a result of this research, we prove that it is possible to assimilate, adapt and transfer technology at low cost, using open source software and following a reproducible research scheme.

  4. Integration of onshore and offshore seismological data to study the seismicity of the Calabrian Region

    D'Alessandro, Antonino; Guerra, Ignazio; D'Anna, Giuseppe; Gervasi, Anna; Harabaglia, Paolo; Luzio, Dario; Stellato, Gilda


    The Pollino Massif marks the transition from the Southern Appenninic to the Calabrian Arc. On the western side it is characterized by a moderately sized seismicity (about 9 M > 4 events in the last 50 years), well documented in the last 400 years. The moment tensor solutions available in this area yields, mainly, normal faults with coherent Southern Appeninic trend. This remains true also for the events that are localized on the calabrian side of Pollino, South of the massif. In most of the Sibari plane, seismic activity is very scarce, while it is again rather marked on its southeastern corner, both onshore and offshore. The above observations point to the perspective that the stress field of a vast portion of Northern Calabria still resembles that of the Southern Appenines. In this frame, it becomes important to investigate the offshore seismicity of the Sibari Gulf and the deformation pattern within the Sibari Plane. The latter might function as a hinge to transfer the deformation of the extensional fault system in the Pollino area to a different offshore fault system. Since return times of larger events might be very long, we need to investigate the true seismic potential of the offshore faults and to verify whether they are truly strike slip or if they could involve relevant thrust or normal components, that would add to the risk that of potentially associated tsunamis. Despite their importance in the understanding of the seismotectonic processes taking place in the Southern Appenninic - Calabrian Arc border and surrounding areas, the seismicity and the seismogenic volumes of the Sibari Gulf until now has not been well characterized due to the lack of offshore seismic stations. The seismicity of the Calabrian is monitored by the Italian National Seismic Network (INSN) managed by Istituto Nazionale di Geofisica e Vulcanologia and by the Calabrian Regional Seismic Network (CRSN) managed by the University of Calabria. Both the network comprise only on

  5. Theoretical Study on Stochastic Modeling of Combined Gravity-Magnetic-Electric-Seismic Inversion and Its Application

    Yan Hanjie; Yan Hong; Li Yunping; Zhang Xiaofeng


    As gravity field, magnetic field, electric field and reismic wave field are all physical fields, their object function, reverse function and compound function are certainly infinite continuously differentiable functions which can be expanded into Taylor (Fourier) series within domain of definition and be further reduced into solving stochastic distribution function of series and statistic inference of optimal approximation. This is thebasis of combined gravity-magnetic-electric-seismic inversion of stochastic modeling. It is an uncertainty modeling technology of combining gravity-magnetic-electric-seismic inversion built on the basis of separation of field and source gravity-magnetic difference-value (D-value) trend surface, taking distribution-independent fault system as its unit, depths of seismic and electric interfaces of interests as its corresponding bivariate compound reverse function of gravity-magnetic anomalies and using high order polynomial (high order trigonometric function) approximating to its series distribution. The difference from current dominant inversion techniques is that, first, it does not respectively create gravity-seismic, magnetic-seismic deterministic inversion model from theoretical model, but combines gravity-magnetic-electric-seismic stochastic inversion model from stochastic model; second, after the concept of equivalent geological body being introduced, using feature of independent variable of gravity-magnetic field functions, taking density and susceptibility related to gravity-magnetic function as default parameters of model, the deterministic model is established owing to better solution to the contradiction of difficulty in identifying strata and less test analytical data for density and susceptibility in newly explored area; third, under assumption of independent parent distribution, a real modeling by strata, the problem of difficult plane closure arising in profile modeling is avoided. This technology has richer and more

  6. Computing seismic damage estimates for buildings within a big city. Bucharest case study.

    Toma-Danila, Dragos; Armas, Iuliana


    The seismic risk analysis of big cities is a very demanding yet necessary task; the modeling of such complex systems requires first of all insightful input data at good resolution, referring to local effects, buildings and socio-economic aspects. Also, seismic risk estimation methods with good confidence levels are needed. Until recently, these requirements were not fulfilled for Bucharest, one of the most endangered capital city in Europe due to earthquakes. Based on 2011 and 2002 census data, standardized according to the framework of the Near-real time System for Estimating the Seismic Damage in Romania (SeisDaRo) through a unique approach and on relevant hazard scenarios, we estimate for the first time the building damage within the city, divided in more than 120 areas. The methodology applied relies on 48 vulnerability curves for buildings, on the Improved Displacement Coefficient Analytical Method included in the SELENA software for computing damage probabilities and on multiple seismic hazard scenarios, including the maximum possible. In order to compare results with real losses we use a scenario based on the 4 March 1977 Vrancea earthquake (7.4 moment-magnitude) that lead to 1424 deaths in Bucharest. By using overlay analysis with satellite imagery and a new methodology integrated in GIS we show how results can be enhanced, reflecting even more local characteristics. Best practices for seismic risk mapping are also expressed. Results are promising and contribute to the mitigation efforts in Bucharest.

  7. Seismic Data Analysis to the Converted Wave Acquisition: A Case Study in Offshore Malaysia

    Latiff, A. H. Abdul; Osman, S. A. A.; Jamaludin, S. N. F.


    Many fields in offshore Malaysia suffer from the presence of shallow gas cloud which is one of the major issues in the basin. Seismic images underneath the gas cloud often show poor resolution which makes the geophysical and geological interpretation difficult. This effect can be noticed from the amplitude dimming, loss of high-frequency energy, and phase distortion. In this work, the subsurface will be analyzed through the geophysical interpretation of the converted P-S data. This P-S converted dataset was obtained through ocean bottom cable (OBC) procedure which was conducted at a shallow gas affected field located in Malaysian Basin. The geophysical interpretation process begin by picking the clear faults system and horizons, followed by thorough post-stack seismic data processing procedure. Finally, the attributes analyses were implemented to the seismic section in order to image the unseen faults system. The interpreted seismic sections show significant improvement in the seismic images, particularly through median filter process. Moreover, the combination of structural smoothing and variance procedure had contributed to the correct faults location interpretation.

  8. Seismic Creep

    National Oceanic and Atmospheric Administration, Department of Commerce — Seismic creep is the constant or periodic movement on a fault as contrasted with the sudden erupture associated with an earthquake. It is a usually slow deformation...

  9. An experimental study on antipersonnel landmine detection using acoustic-to-seismic coupling.

    Xiang, Ning; Sabatier, James M


    An acoustic-to-seismic system to detect buried antipersonnel mines exploits airborne acoustic waves penetrating the surface of the ground. Acoustic waves radiating from a sound source above the ground excite Biot type I and II compressional waves in the porous soil. The type I wave and type II waves refract toward the normal and cause air and soil particle motion. If a landmine is buried below the surface of the insonified area, these waves are scattered or reflected by the target, resulting in distinct changes to the acoustically coupled ground motion. A scanning laser Doppler vibrometer measures the motion of the ground surface. In the past, this technique has been employed with remarkable success in locating antitank mines during blind field tests [Sabatier and Xiang, IEEE Trans. Geosci. Remote Sens. 39, 1146-1154 (2001)]. The humanitarian demining mission requires an ability to locate antipersonnel mines, requiring a surmounting of additional challenges due to a plethora of shapes and smaller sizes. This paper describes an experimental study on the methods used to locate antipersonnel landmines in recent field measurements.

  10. Study on Seismic Performance of a Stiffened Steel Plate Shear Wall with Slits

    Jin-yu Lu


    Full Text Available To determine the force mechanism for the steel plate shear wall with slits, the pushover analysis method was used in this study. An estimated equation for the lateral bearing capacity which considered the effect of edge stiffener was proposed. A simplified elastic-plastic analytical model for the stiffened steel slit wall composed of beam elements was presented, where the effects of edge stiffeners were taken into account. The wall-frame analysis model was established, and the geometric parameters were defined. Pushover analysis of two specimens was carried out, and the analysis was validated by comparing the results from the experiment, the shell element model, and a simplified model. The simplified model provided a good prediction of the lateral stiffness and the strength of the steel slit wall, with less than 10% error compared with the experimental results. The mutual effects of the bearing wall and the frame were also predicted correctly. In the end, the seismic performance evaluation of a steel slit wall-frame structure was presented. The results showed that the steel slit wall could prevent the beams and columns from being damaged by an earthquake and that the steel slit wall was an efficient energy dissipation component.

  11. Experimental study on the seismic behavior of high strength concrete filled double-tube columns

    Qian, Jiaru; Li, Ningbo; Ji, Xiaodong; Zhao, Zuozhou


    To study the seismic behavior of high strength concrete filled double-tube (CFDT) columns, each consisting of an external square steel tube and an internal circular steel tube, quasi-static tests on eight CFDT column specimens were conducted. The test variables included the width-to-thickness ratio ( β 1) and the area ratio ( β 2) of the square steel tube, the wall thickness of the circular steel tube, and the axial force (or the axial force ratio) applied to the CFDT columns. The test results indicate that for CFDT columns with a square steel tube with β 1 of 50.1 and 24.5, local buckling of the specimen was found at a drift ratio of 1/150 and 1/50, respectively. The lateral force-displacement hysteretic loops of all specimens were plump and stable. Reducing the width-to-thickness ratio of the square steel tube, increasing its area ratio, or increasing the wall thickness of the internal circular steel tube, led to an increased flexural strength and deformation capacity of the specimens. Increasing the design value of the axial force ratio from 0.8 to 1.0 may increase the flexural strength of the specimens, while it may also decrease the ultimate deformation capacity of the specimen with β 1 of 50.1.

  12. Aftershock Study of the 2014 Duncan, Arizona Mw = 5.2 Earthquake Using Local Seismic Data

    Dorn, K. M.; Young, J.; Barstow, N.; Peavey, H.; Braunmiller, J.


    On June 29, 2014, at 4:59:35.4 UTC, a Mw = 5.2 earthquake struck near Duncan, just west of the Arizona-New Mexico border. This event is the strongest instrumentally recorded earthquake yet in southeastern Arizona, which experiences low seismicity due to slow roughly east-west-trending extension in the transition zone between the Basin and Range region and the stable Colorado Plateau to the north. An approximately 15-by-20-km-wide temporary network of four short-period and two broadband seismometers was deployed to study the aftershock sequence, as the nearest permanent stations are located over one hundred kilometers away. We used the BRTT Antelope "dbdetect" and "dbgrassoc" tools to obtain locations for about 10,000 aftershocks from July 8 through August 28, 2014, when at least four local stations were operational. Our preliminary results suggest that most of the activity occurred in a north-south-elongated area, within 32.57-32.64° N and 109.11-109.15° W and about 4-7 km deep. We have not observed distinct event migrations, but found several event clusters within the aftershock region that were active for short time periods, implying a complex pattern of strain release. The aftershock sequence has continued for more than two years after the mainshock event.

  13. Seismic facies; Facies sismicas

    Johann, Paulo Roberto Schroeder [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao Corporativo. Gerencia de Reservas e Reservatorios]. E-mail:


    The method presented herein describes the seismic facies as representations of curves and vertical matrixes of the lithotypes proportions. The seismic facies are greatly interested in capturing the spatial distributions (3D) of regionalized variables, as for example, lithotypes, sedimentary facies groups and/ or porosity and/or other properties of the reservoirs and integrate them into the 3D geological modeling (Johann, 1997). Thus when interpreted as curves or vertical matrixes of proportions, seismic facies allow us to build a very important tool for structural analysis of regionalized variables. The matrixes have an important application in geostatistical modeling. In addition, this approach provides results about the depth and scale of the wells profiles, that is, seismic data is integrated to the characterization of reservoirs in depth maps and in high resolution maps. The link between the different necessary technical phases involved in the classification of the segments of seismic traces is described herein in groups of predefined traces of two approaches: a) not supervised and b) supervised by the geological knowledge available on the studied reservoir. The multivariate statistical methods used to obtain the maps of the seismic facies units are interesting tools to be used to provide a lithostratigraphic and petrophysical understanding of a petroleum reservoir. In the case studied these seismic facies units are interpreted as representative of the depositional system as a part of the Namorado Turbiditic System, Namorado Field, Campos Basin.Within the scope of PRAVAP 19 (Programa Estrategico de Recuperacao Avancada de Petroleo - Strategic Program of Advanced Petroleum Recovery) some research work on algorithms is underway to select new optimized attributes to apply seismic facies. One example is the extraction of attributes based on the wavelet transformation and on the time-frequency analysis methodology. PRAVAP is also carrying out research work on an

  14. Seismic seiches

    McGarr, Arthur; Gupta, Harsh K.


    Seismic seiche is a term first used by Kvale (1955) to discuss oscillations of lake levels in Norway and England caused by the Assam earthquake of August 15, 1950. This definition has since been generalized to apply to standing waves set up in closed, or partially closed, bodies of water including rivers, shipping channels, lakes, swimming pools and tanks due to the passage of seismic waves from an earthquake.

  15. Applying the seismic interferometry method to vertical seismic profile data using tunnel excavation noise as source

    Jurado, Maria Jose; Teixido, Teresa; Martin, Elena; Segarra, Miguel; Segura, Carlos


    In the frame of the research conducted to develop efficient strategies for investigation of rock properties and fluids ahead of tunnel excavations the seismic interferometry method was applied to analyze the data acquired in boreholes instrumented with geophone strings. The results obtained confirmed that seismic interferometry provided an improved resolution of petrophysical properties to identify heterogeneities and geological structures ahead of the excavation. These features are beyond the resolution of other conventional geophysical methods but can be the cause severe problems in the excavation of tunnels. Geophone strings were used to record different types of seismic noise generated at the tunnel head during excavation with a tunnelling machine and also during the placement of the rings covering the tunnel excavation. In this study we show how tunnel construction activities have been characterized as source of seismic signal and used in our research as the seismic source signal for generating a 3D reflection seismic survey. The data was recorded in vertical water filled borehole with a borehole seismic string at a distance of 60 m from the tunnel trace. A reference pilot signal was obtained from seismograms acquired close the tunnel face excavation in order to obtain best signal-to-noise ratio to be used in the interferometry processing (Poletto et al., 2010). The seismic interferometry method (Claerbout 1968) was successfully applied to image the subsurface geological structure using the seismic wave field generated by tunneling (tunnelling machine and construction activities) recorded with geophone strings. This technique was applied simulating virtual shot records related to the number of receivers in the borehole with the seismic transmitted events, and processing the data as a reflection seismic survey. The pseudo reflective wave field was obtained by cross-correlation of the transmitted wave data. We applied the relationship between the transmission

  16. Research and development studies on the seismic behaviour of the PEC fast reactor (safety analysis detailed report no. 8)

    Martelli, A.; Forni, M.; Masoni, P.; Maresca, G.; Castoldi, A.; Muzzi, F. (ENEA, Rome (Italy); Ansaldo Spa, Genoa (Italy); ISMES Spa, Bergamo (Italy))


    This paper presents the main features and results of the numerical and experimental studies that were carried out by ENEA (Italian Commission for Alternative Energy Sources) for the seismic verification of the Italian PEC fast reactor test facility. More precisely, the paper focuses on the wide-ranging research and development programme that has been performed (and recently completed) on the reactor building, the reactor-block, the main vessel, the core and the shutdown system. The needs of these detailed studies are stressed and the feed-backs on the design, necessary safisfy the seismic safety requirements, are recalled. The general validity of the analyses in the framework of the research and development activities for nuclear reactor is also pointed out.


    Dawson, Phillip B.; Rodrigues da Silva, Antonio; Iyer, H.M.; Evans, John R.


    A 16 station array was operated over the 200 km**2 central portion of Sao Miguel utilizing 8 permanent Instituto Nacional de Meterologia e Geofisica stations and 8 USGS portable stations. Forty four local events with well constrained solutions and 15 regional events were located. In addition, hundreds of unlocatable seismic events were recorded. The most interesting seismic activity occurred in a swarm on September 6 and 7, 1983 when over 200 events were recorded in a 16 hour period. The seismic activity around Agua de Pau was centered on the east and northeast slopes of the volcano. The data suggest a boiling hydrothermal system beneath the Agua de Pau volcano, consistent with a variety of other data.

  18. Seismic Data Interpretation: A Case Study of Southern Sindh Monocline, Lower Indus Basin, Pakistan

    Shabeer Ahmed Abbasi


    Full Text Available The Sindh monocline in Lower Indus Basin is an important oil and gas producing area of Pakistan where a large number of oil, gas and condensate fields have been discovered from structural traps. This research involves the interpretation of stratigraphic and structural styles of Sindh Monocline using 2D (Two-Dimensional seismic reflection and well log. Four reflectors of different formations have been marked and were named as Reflector-1 as of Khadro Formation, Reflector-2 as Upper Goru Member, Reflector-3 as Lower Goru Formation and Reflector-4 as Chiltan Limestone. The average depth of Khadro Formation was marked at 449.0m, Upper Goru Member at 968m, Lower Goru Formation at 1938m and Chiltan Limestone at 2943m. Faults were marked on seismic sections which collectively form horsts and grabens which is the evidence of extensional tectonic in the area. Seismic interpretation was carried out through window based Kingdom Software

  19. Seismic methods for resource exploration in enhanced geothermal systems

    Gritto, Roland; Majer, Ernest L.


    A finite-difference modeling study of seismic wave propagation was conducted to determine how to best investigate subsurface faults and fracture zones in geothermal areas. The numerical model was created based on results from a previous seismic reflection experiment. A suite of fault models was investigated including blind faults and faults with surface expressions. The seismic data suggest that blind faults can be detected by a sudden attenuation of seismic wave amplitudes, as long the fault is located below the receiver array. Additionally, a conversion from P- to S-waves indicates the reflection and refraction of the P-waves while propagating across the fault. The drop in amplitudes and the excitation of S-waves can be used to estimate the location of the fault at depth. The accuracy of the numerical modeling depends on the availability of a priori in situ information (velocity and density) from borehole experiments in the geothermal area.


    Kh. N. Mazhiev


    Full Text Available The issues of regulation of seismic loads on structures using kinematic supports of highstrength concrete on the impregnated coarse aggregate and seismic isolation bearings Belleville. The results of experimental studies related to the obtaining of a new coarse aggregate and construction of seismic isolation bearings. Addresses the issues of interaction forces in thehemispherical supports vibration process.

  1. Study on the application of seismic sedimentology in a stratigraphic-lithologic reservoir in central Junggar Basin

    Yu, Yixin; Xia, Zhongmou


    This paper discusses the research idea of description for stratigraphic-lithologic reservoir based on seismic sedimentology methods. The sandstone reservoir of Jurrassic XiShanyao Formation in Junggar Basin is studied according to the theory and approaches of seismic sedimentology. By making full use of borehole data, the technologies of layer correlation based on the stratigraphic sequence framework, the forward seismic modeling, the stratal slicing and lithologic inversion are applied. It describes the range of denudation line, the distribution characteristics of sedimentary facies of the strata, the vertical and horizontal distribution of sand bodies and the favourable oil-gas bearing prospective area. The results shows that study area are dominated braided delta deposition including underwater distributary channel and distributary bay microfacies, the nip-out lines of the formation are northeast to southwest from north to south, the second Middle Jurassic sand body is the most widely distributed one among three sand bodies, the prospective oil-gas bearing area located in the south part and around the YG2 well area. The study result is effective on the practice of exploration in study area.

  2. Patient acceptance and clinical impact of Bravo monitoring in patients with previous failed catheter-based studies.

    Sweis, R; Fox, M; Anggiansah, R; Anggiansah, A; Basavaraju, K; Canavan, R; Wong, T


    Standard pH monitoring is performed over 24 h with a naso-oesophageal catheter (C-pH). Limitations include naso-pharyngeal discomfort, nausea and social embarrassment resulting in reduced reflux-provoking activities. Recently a catheter-free pH-monitoring technique has become available. The tolerability and diagnostic yield of this system in patients who failed standard monitoring remain unknown. To examine the tolerability and diagnostic outcome of catheter-free pH-monitoring technique in patients who failed standard monitoring. Patients referred for C-pH and catheter-free pH monitoring completed a tolerability questionnaire. Acid exposure in the distal oesophagus and symptom index (SI) were reviewed. Over 4 years, 883/1751 (50%) of patients with typical reflux symptoms referred for C-pH were diagnosed with gastro-oesophageal reflux disease (GERD) based on a pathological percentage time acid exposure (%time pH patients failed C-pH and, of these, 129 successfully completed 2-day catheter-free pH monitoring. Ninety-eight (76%) of these patients had a pathological percentage pH patients (P patients who had previously failed C-pH; catheter-free pH monitoring assists the definitive diagnosis of GERD in this group.

  3. Ground Truth Location of Earthquakes by Use of Ambient Seismic Noise From a Sparse Seismic Network: A Case Study in Western Australia

    Zeng, Xiangfang; Xie, Jun; Ni, Sidao


    The estimated Green's function (EGF) extracted from the ambient seismic noise cross-correlation function (NCF) enables valuable calibration of surface wave propagation along the path connecting seismic stations. Such calibration is adopted in a new method for ground truth location of earthquakes, achieved from the location relative to a seismic station. The surface wave group travel times were obtained from the NCFs between a station near the earthquake and remote stations. The differential travel times from the NCFs and the surface wave of the earthquake were used in a relative location procedure. When this method was applied to earthquake location with only six seismic stations in western Australia, the location of the Mw 4.1 Kalannie (September 21, 2005) earthquake was found to be accurate to within 2 km compared with the ground truth location with InSAR for which azimuth coverage of seismic stations is preferable. Synthetic tests suggest that the group travel time is slightly affected by focal mechanism and focal depth, thus unknown earthquake source parameters did not introduce substantial bias to earthquake location with the group travel time method.

  4. Seismicity study in Pournari reservoir area (W. Greece) 1981-2010

    Pavlou, K.; Drakatos, G.; Kouskouna, V.; Makropoulos, K.; Kranis, H.


    The spatial-temporal evolution of seismicity is examined, during the initial impoundment of Pournari reservoir located on Arachthos River (Western Greece), as well as for the next 30 years. The results show that, despite the relatively moderate-to-high seismicity from west to east, there is no remarkable earthquake in the vicinity before the first reservoir impoundment. Immediately after the impoundment (January 1981), and during the first 4 months, a considerable number of low-magnitude seismic events were recorded in the broader area of the dam. Moreover, two independent major events occurred on March 10, 1981 ( M L = 5.6) and April 10, 1981 ( M L = 4.7) with focal depths 13 and 10 km, respectively. The detailed analysis of the two corresponding aftershock sequences shows that they present different behaviors (e.g., larger b-value and lower magnitude of the main aftershock) than that of other aftershock sequences in Greece. This seismicity is probably due to triggering, via the water loading mechanism and the undrained response due to a flysch appearance on the reservoir basement. The activation of the thrust fault may be attributed to the bulging of evaporites that characterize the disordered structure of W. Greece, via possible water intake. The detailed processing of the recorded seismicity during the period 1982-2010, in comparison with the variations of Pournari Dam water level, shows an increase of shallow seismicity ( h ≤ 5 km) in the vicinity of the reservoir up to a 10-km distance—in contrast to the initial period, characterized by a number of deeper events due to the background response change from undrained to drained status.

  5. Study on the Determination of the Significant National Seismic Monitoring and Protection Regions

    Zhang Guomin; Fu Zhengxiang; Wang Xiaoqing; Liu Guiping


    The paper describes firstly the principies and scientific train of thought involved in determining the significant seismic monitoring and protection regions (SSMPR) in China.The principles include the gradation principle, i.e.the national level SSMPR and the provincial level SSMPR,the principle of highlighting priorities,namely,the area of an SSMPR should be a fraction of the total area of the country or of the respective province,but the earthquake losses incurred in SSMPR should be a major proportion of the national or provincial ones.The scientific train of thought adopted is to determine the SSMPR on the basis of seismic hazard assessment and loss estimation.Secondly,it reviews the achievements in determining the SSMPRs for the period from 1996 to 2005.The result shows that 10 strong earthquakes occurred during that period in the areas with earthquake monitoring and prediction capability available on the Chinese continent, 8 of which occurred in SSMPRs with the economic loss and death toll accounting for 67% and 92% of the total loss on the Chinese mainland.Lastly,the paper introduces preparatory research for determining the SSMPR for the period from 2006 to 2020,including decade-scale mid-and long-range seismic risk assessment based on seismology,seismogeology,geodesy,earthquake engineering,sociology and stochastics and so on,and the national seismic risk probability map,the seismic hazard (intensity) map,earthquake disaster losses map and the comprehensive seismic risk index,etc.obtained for the period of 2006 to 2020.

  6. Study of earthquakes using a borehole seismic network at Koyna, India

    Gupta, Harsh; Satyanarayana, Hari VS; Shashidhar, Dodla; Mallika, Kothamasu; Ranjan Mahato, Chitta; Shankar Maity, Bhavani


    Koyna, located near the west coast of India, is a classical site of artificial water reservoir triggered earthquakes. Triggered earthquakes started soon after the impoundment of the Koyna Dam in 1962. The activity has continued till now including the largest triggered earthquake of M 6.3 in 1967; 22 earthquakes of M ≥ 5 and several thousands smaller earthquakes. The latest significant earthquake of ML 3.7 occurred on 24th November 2016. In spite of having a network of 23 broad band 3-component seismic stations in the near vicinity of the Koyna earthquake zone, locations of earthquakes had errors of 1 km. The main reason was the presence of 1 km thick very heterogeneous Deccan Traps cover that introduced noise and locations could not be improved. To improve the accuracy of location of earthquakes, a unique network of eight borehole seismic stations surrounding the seismicity was designed. Six of these have been installed at depths varying from 981 m to 1522 m during 2015 and 2016, well below the Deccan Traps cover. During 2016 a total of 2100 earthquakes were located. There has been a significant improvement in the location of earthquakes and the absolute errors of location have come down to ± 300 m. All earthquakes of ML ≥ 0.5 are now located, compared to ML ≥1.0 earlier. Based on seismicity and logistics, a block of 2 km x 2 km area has been chosen for the 3 km deep pilot borehole. The installation of the borehole seismic network has further elucidated the correspondence between rate of water loading/unloading the reservoir and triggered seismicity.

  7. Study of Vertical Seismic Response of Concrete Self-Anchored Suspension Bridges

    刘春城; 石磊; 张哲


    Based on the variational prineiple of incomplete generalized potential energy with large deflection, the vertical nonlinear vibrational differential equation of self-anchored suspension bridge is presented by taking the effect of coupling of flexural and axial action into consideration. The linear vertical equation is obtained by omitting the nonlinear term, and the pseudo excitation method(PEM). Taking the self-anchored concrete suspension bridge over Lanqi Songhua river for an example, the expected peak responses of main beam, towers and cables are calculated. And the seismic spatial effects on vertical seismic response of self-anchored suspension bridges are discussed.

  8. Seismic Consequence Abstraction

    M. Gross


    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  9. A Study of the Relationship between Previous Exposure to Education and Practice-Teaching Performance at the University of Ife.

    Olatunji, S. A.


    A study to identify relationships between the amount of exposure students have to education (as a discipline) and their student teaching performances is reported. Students attending the University of Ife from 1973-1976 were studied. A positive relationship was discovered, but other factors need to be researched further. (MLW)

  10. Integrated geologic and geophysical studies of North American continental intraplate seismicity

    Van Lanen, X.; Mooney, W.D.


    The origin of earthquakes within stable continental regions has been the subject of debate over the past thirty years. Here, we examine the correlation of North American stable continental region earthquakes using five geologic and geophysical data sets: (1) a newly compiled age-province map; (2) Bouguer gravity data; (3) aeromagnetic anomalies; (4) the tectonic stress field; and (5) crustal structure as revealed by deep seismic-reflection profiles. We find that: (1) Archean-age (3.8-2.5 Ga) North American crust is essentially aseismic, whereas post-Archean (less than 2.5 Ga) crust shows no clear correlation of crustal age and earthquake frequency or moment release; (2) seismicity is correlated with continental paleorifts; and (3) seismicity is correlated with the NE-SW structural grain of the crust of eastern North America, which in turn reflects the opening and closing of the proto- and modern Atlantic Ocean. This structural grain can be discerned as clear NE-SW lineaments in the Bouguer gravity and aeromagnetic anomaly maps. Stable continental region seismicity either: (1) follows the NE-SW lineaments; (2) is aligned at right angles to these lineaments; or (3) forms clusters at what have been termed stress concentrators (e.g., igneous intrusions and intersecting faults). Seismicity levels are very low to the west of the Grenville Front (i.e., in the Archean Superior craton). The correlation of seismicity with NE-SW-oriented lineaments implies that some stable continental region seismicity is related to the accretion and rifting processes that have formed the North American continental crust during the past 2 b.y. We further evaluate this hypothesis by correlating stable continental region seismicity with recently obtained deep seismic-reflection images of the Appalachian and Grenville crust of southern Canada. These images show numerous faults that penetrate deep (40 km) into the crust. An analysis of hypocentral depths for stable continental region earthquakes

  11. Advancing internal erosion monitoring using seismic methods in field and laboratory studies

    Parekh, Minal L.

    embankment surface. Analysis of root mean squared amplitude and AE threshold counts indicated activity focused at the toe in locations matching the sand boils. This analysis also compared the various detection methods employed at the 2012 test to discuss a timeline of detection related to observable behaviors of the structure. The second area of research included designing and fabricating an instrumented laboratory apparatus for investigating active seismic wave propagation through soil samples. This dissertation includes a description of the rigid wall permeameter, instrumentation, control, and acquisitions systems along with descriptions of the custom-fabricated seismic sensors. A series of experiments (saturated sand, saturated sand with a known static anomaly placed near the center of the sample, and saturated sand with a diminishing anomaly near the center of the sample) indicated that shear wave velocity changes reflected changes in the state of stress of the soil. The mean effective stress was influenced by the applied vertical axial load, the frictional interaction between the soil and permeameter wall, and the degree of preloading. The frictional resistance was sizeable at the sidewall of the permeameter and decreased the mean effective stress with depth. This study also included flow tests to monitor changes in shear wave velocities as the internal erosion process started and developed. Shear wave velocity decreased at voids or lower density zones in the sample and increased as arching redistributes loads, though the two conditions compete. Finally, the social and political contexts surrounding nondestructive inspection were considered. An analogous approach utilized by the aerospace industry was introduced: a case study comparing the path toward adopting nondestructive tools as standard practices in monitoring aircraft safety. Additional lessons for dam and levee safety management were discussed from a Science, Technology, Engineering, and Policy (STEP

  12. Automatic Recognition of Seismic Intensity Based on RS and GIS: A Case Study in Wenchuan Ms8.0 Earthquake of China

    Qiuwen Zhang


    Full Text Available In recent years, earthquakes have frequently occurred all over the world, which caused huge casualties and economic losses. It is very necessary and urgent to obtain the seismic intensity map timely so as to master the distribution of the disaster and provide supports for quick earthquake relief. Compared with traditional methods of drawing seismic intensity map, which require many investigations in the field of earthquake area or are too dependent on the empirical formulas, spatial information technologies such as Remote Sensing (RS and Geographical Information System (GIS can provide fast and economical way to automatically recognize the seismic intensity. With the integrated application of RS and GIS, this paper proposes a RS/GIS-based approach for automatic recognition of seismic intensity, in which RS is used to retrieve and extract the information on damages caused by earthquake, and GIS is applied to manage and display the data of seismic intensity. The case study in Wenchuan Ms8.0 earthquake in China shows that the information on seismic intensity can be automatically extracted from remotely sensed images as quickly as possible after earthquake occurrence, and the Digital Intensity Model (DIM can be used to visually query and display the distribution of seismic intensity.

  13. New constraints for site-effect characterization from seismic noise analysis in southern Italy. San Fele case study

    Simona Petrosino


    Full Text Available In the framework of ground-motion amplification analysis for southern Italy, the main target of this study is to provide new constraints on one-dimensional, shallow-velocity profiles for a site in the San Fele area near the city of Potenza (southern Italy where a permanent Irpinia Seismic Network (ISNet seismic station is installed. Ambient noise vibrations were recorded during a seismic survey in San Fele, and the data acquired were used to define the shallow shear-wave velocity profiles and thicknesses of the shallow soil layers, through analysis of the dispersion characteristics of the surface waves. Single station and array techniques were used to obtain robust results, which show relatively flat curves of the H/V spectral ratios and variations in shear-wave velocities confined to the first 50 m in depth. On the basis of these results for the San Fele site, the present study aims to delineate a standard procedure that can be systematically applied to all of the other ISNet stations to improve site characterization. This will allow more accurate evaluation of peak ground-motion quantities (e.g. peak ground acceleration, peak ground velocity at rock sites for use in shake-map analysis.

  14. Seismicity study of volcano-tectonic in and around Tangkuban Parahu active volcano in West Java region, Indonesia

    Ry, Rexha V.; Priyono, A.; Nugraha, A. D.; Basuki, A.


    Tangkuban Parahu is one of the active volcano in Indonesia located about 15 km northern part of Bandung city. The objective of this study is to investigate the seismic activity in the time periods of January 2013 to December 2013. First, we identified seismic events induced by volcano-tectonic activities. These micro-earthquake events were identified as having difference of P-wave and S-wave arrival times less than three seconds. Then, we constrained its location of hypocenter to locate the source of the activities. Hypocenter determination was performed using adaptive simulated annealing method. Using these results, seismic tomographic inversions were conducted to image the three-dimensional velocity structure of Vp, Vs, and the Vp/Vs ratio. In this study, 278 micro-earthquake events have been identified and located. Distribution of hypocenters around Tangkuban Parahu volcano forms an alignment structure and may be related to the stress induced by magma below, also movement of shallow magma below Domas Crater. Our preliminary tomographic inversion results indicate the presences of low Vp, high Vs, and low Vp/Vs ratio that associate to accumulated young volcanic eruption products and hot material zones.

  15. Integrated seismic stochastic inversion and multi-attributes to delineate reservoir distribution: Case study MZ fields, Central Sumatra Basin

    Haris, A.; Novriyani, M.; Suparno, S.; Hidayat, R.; Riyanto, A.


    This study presents the integration of seismic stochastic inversion and multi-attributes for delineating the reservoir distribution in term of lithology and porosity in the formation within depth interval between the Top Sihapas and Top Pematang. The method that has been used is a stochastic inversion, which is integrated with multi-attribute seismic by applying neural network Probabilistic Neural Network (PNN). Stochastic methods are used to predict the probability mapping sandstone as the result of impedance varied with 50 realizations that will produce a good probability. Analysis of Stochastic Seismic Tnversion provides more interpretive because it directly gives the value of the property. Our experiment shows that AT of stochastic inversion provides more diverse uncertainty so that the probability value will be close to the actual values. The produced AT is then used for an input of a multi-attribute analysis, which is used to predict the gamma ray, density and porosity logs. To obtain the number of attributes that are used, stepwise regression algorithm is applied. The results are attributes which are used in the process of PNN. This PNN method is chosen because it has the best correlation of others neural network method. Finally, we interpret the product of the multi-attribute analysis are in the form of pseudo-gamma ray volume, density volume and volume of pseudo-porosity to delineate the reservoir distribution. Our interpretation shows that the structural trap is identified in the southeastern part of study area, which is along the anticline.

  16. Marine fouling community in the Eastern harbour of Alexandria, Egypt compared with four decades of previous studies



    Full Text Available The aim of the present study is to compare the fouling communities between the years 1960 and 1999 in the Eastern harbour of Alexandria, Egypt and to study the main factors that may be controlling these communities. This comparison is based on monthly durations of panel immersion. By using roughened white polystyrene test panels (12.5x12.5 cm, monthly samples of marine fouling were collected from the harbour from October 1998 through September 1999. It is clear that a remarkable variation in number and diversity of fouling communities throughout the last four decades is evident. The minimum diversities were recorded during the studies of 1960 and 1970 (19 and 20 species respectively, while the maximum diversity (35 species was achieved during the 1991 study. Moreover, a small shift among the four dominant groups (Polychaeta, Cirripedia, Bryozoa and Amphipoda was noted during the four decades of the studies. The present comparison indicated that many factors may contribute to this variation, of which nutrient enrichment is the most important and the nature of the applied test panel is lees so.

  17. Seismic hazard assessment of Iran

    M. Ghafory-Ashtiany


    Full Text Available The development of the new seismic hazard map of Iran is based on probabilistic seismic hazard computation using the historical earthquakes data, geology, tectonics, fault activity and seismic source models in Iran. These maps have been prepared to indicate the earthquake hazard of Iran in the form of iso-acceleration contour lines, and seismic hazard zoning, by using current probabilistic procedures. They display the probabilistic estimates of Peak Ground Acceleration (PGA for the return periods of 75 and 475 years. The maps have been divided into intervals of 0.25 degrees in both latitudinal and longitudinal directions to calculate the peak ground acceleration values at each grid point and draw the seismic hazard curves. The results presented in this study will provide the basis for the preparation of seismic risk maps, the estimation of earthquake insurance premiums, and the preliminary site evaluation of critical facilities.

  18. Scientific results from the deepened Lopra-1 borehole, Faroe Islands: Borehole seismic studies of a volcanic succession from the Lopra-1/1A borehole in the Faroe Islands, northern North Atlantic

    Cowper, David


    Full Text Available Extruded basalt flows overlying sedimentary sequences present a challenge to hydrocarbon exploration using reflection seismic techniques. The Lopra-1/1A re-entry well on the Faroese island of Suðuroy allowed us to study the seismic characteristics of a thick sequence of basalt flows from well logs and borehole seismic recordings. Data acquired during the deepening operation in 1996 are presented here.The re-entry well found that the seismic event at 2340 m, prognosed from the pre-drill Vertical Seismic Profile (VSP as a decrease in impedance, was not base basalt and the deepened well remainedwithin the lower series basalts. Nonetheless, compressional and shear sonic logs and a density log were recorded over the full open hole interval. These allowed a firm tie to be made with the reflectedwavefield from a new VSP. The sonic logs show a compressional to shear wavespeed ratio of 1.84 which is almost constant with depth. Sonic compressional wavespeeds are 3% higher than seismicvelocities, suggesting dispersion in the basalt flows. Azimuthal anisotropy was weakly indicated by the shear sonic log but its orientation is consistent with the directions of mapped master joints in the vicinity of the well.The VSP downgoing compressional wavelet shows good persistence, retaining a dominant period of 28 ms at 3510 m depth. Average vertical velocity is 5248 m/s, higher than previously reported.Attenuation can largely be modelled by geometrical spreading and scattering loss, consistent with other studies. Within the piled flows, the effective Q from scattering is about 35. Elastic layeredmedium modelling shows some hope that a mode-converted shear wave may be observed at moderate offsets. Like its predecessor, the 1996 VSP indicates a decrease in impedance below the final depth ofthe well. However, it is unlikely to be basement or sediment and is probably an event within the volcanic sequence.

  19. Modelling of NW Himalayan Seismicity

    Bansal, A. R.; Dimri, V. P.


    The northwest Himalaya is seismicity active region due to the collision of Indian and Eurasian plates and experienced many large earthquakes in past. A systematic analysis of seismicity is useful for seismic hazard estimation of the region. We analyzed the seismicity of northwestern Himalaya since 1980. The magnitude of completeness of the catalogue is carried out using different methods and found as 3.0. A large difference in magnitude of completeness is found using different methods and a reliable value is obtained after testing the distribution of magnitudes with time. The region is prone to large earthquake and many studied have shown that seismic activation or quiescence takes place before large earthquakes. We studied such behavior of seismicity based on Epidemic Type Aftershock Sequence (ETAS) model and found that a stationary ETAS model is more suitable for modelling the seismicity of this region. The earthquake catalogue is de-clustered using stochasting approach to study behavior of background and triggered seismicity. The triggered seismicity is found to have shallower depths as compared to the background events.

  20. Probabilistic Studies on Seismic Fragility of Different Pipe Sizes Based on Monotonic Experimental Tests

    BuSeog Ju


    Full Text Available This paper presents the seismic fragility of piping systems based on monotonic experimental tests. The fragility, conditional probability of failure for a given level of intensity measure, generally used to evaluate the structural safety and indentify the fault tree with respect to seismically induced failures. The nonlinear FE models of threaded T-joint systems based on monotonic experimental results were developed in OpenSees, using the ElasticPPGap material. In order to evaluate the seismic fragility of Tjoint piping systems, 1-inch and 2-inch threaded T-joint systems, were incorporated with main hospital piping system, and multiple nonlinear time history analyses related to Monte Carlo simulation were conducted. Consequently, seismic fragility of piping system at 1-inch and 2-inch threaded T-joint connections corresponding to ductility level was developed. It was interesting to observe that 2-inch threaded T-joint was more fragile rather than 1-inch threaded T-joint, based on the nonlinear FE model by monotonic tests and also location 1 was more fragile rather than location 2 for both 1-inch and 2-inch T-joint.

  1. Large-scale seismic isolation through regulated liquefaction: a feasibility study

    Mousavi, Seyed Amin; Bastami, Morteza; Zahrai, Seyed Mehdi


    Using controlled liquefaction, a seismic isolation technique is introduced by which a large area with dozens of structures can be seismically isolated. The proposed Large Scale Seismic Isolation (LSSI) is in many ways similar to conventional base isolations. The required bearing is provided by a fully undrained pre-saturated liquefiable layer which has substantial vertical stiffness/capacity and minimal lateral stiffness. Moreover, required energy dissipation would be provided through material damping and Biot flow-induced damping within the liquefied layer. LSSI consists of a thick nonliquefiable crust layer and an underlying engineered pre-saturated liquefiable layer bounded by two impermeable thin clay layers. The liquefiable layer should be designed to trigger liquefaction as soon as possible within the early seconds of a design level seismic event. Adopting the energy-based GMP liquefaction theory, optimum gradation of the liquefiable layer is also investigated. It turned out that LSSI would effectively reduce acceleration response spectrum within short to medium periods. Contribution of the proposed LSSI is more pronounced in the case of stronger ground motions such as near field events as well as ground motions with longer return periods.

  2. Experimental and analytical studies on the seismic behavior of conventional and hybrid braced frames

    Lai, Jiun-Wei

    This dissertation summarizes both experimental and analytical studies on the seismic response of conventional steel concentrically braced frame systems of the type widely used in North America, and preliminary studies of an innovative hybrid braced frame system: the Strong-Back System. The research work is part of NEES small group project entitled "International Hybrid Simulation of Tomorrow's Braced Frames." In the experimental phase, a total of four full-scale, one-bay, two-story conventional braced frame specimens with different bracing member section shapes and gusset plate-to-beam connection details were designed and tested at the NEES Berkeley Laboratory. Three braced frame specimens were tested quasi-statically using the same predefined loading protocol to investigate the inelastic cyclic behavior of code-compliant braced frames at both the global and local level. The last braced frame specimen was nearly identical to one of those tested quasi-statically. However, it was tested using hybrid simulation techniques to examine the sensitivity of inelastic behavior on loading sequence and to relate the behavior observed to different levels of seismic hazard. Computer models of the test specimens were developed using two different computer software programs. In the software framework OpenSees fiber-based line elements were used to simulate global buckling of members and yielding and low-cycle fatigue failure at sections. The LS-DYNA analysis program was also used to model individual struts and the test specimens using shell elements with adaptive meshing and element erosion features. This program provided enhanced ability to simulate section local buckling, strain concentrations and crack development. The numerical results were compared with test results to assess and refine and the ability of the models to predict braced frame behavior. A series of OpenSees numerical cyclic component simulations were then conducted using the validated modeling approach. Two

  3. A cross-sectional study of personality traits in women previously treated or untreated for alcohol use disorders

    Sundh Valter


    Full Text Available Abstract Background A better understanding of the relationship between treatment-seeking for alcohol problems and personality traits could give useful insight in factors promoting or hindering treatment for alcohol use disorders (AUD. The aim of this study was to analyze the associations between treatment-seeking for AUD, personality traits, and psychiatric co-morbidity in women. The study was based on pooled cross-sectional data from three population based samples and one clinical sample (n = 1,339. Comparisons were made between treated and untreated women with AUD, and between those with resolved and unresolved AUD. Results A stepwise logistic regression model showed that treatment-seeking for AUD was not associated with personality traits. Among women with lifetime AUD (n = 217, those who had been treated (n = 42 had significantly higher scores than untreated women (n = 175 on three personality traits of the Karolinska Scales of Personality (KSP; somatic anxiety, muscular tension, and guilt. Women with resolved AUD, who had received treatment (n = 23 had significantly higher scores on scales measuring somatic anxiety, psychic anxiety, muscular tension, irritability, and guilt than untreated women with resolved AUD. The latter group resembled women without AUD on most personality traits. There were no differences in occurrence of lifetime psychiatric disorders between the treated and the untreated women, whereas treated women with current AUD had increased risk of lifetime anxiety (OR: 3.1, 95% CI: 1.1–8.7. Conclusion Treatment-seeking was not associated with personality traits in this study. Still, it can be concluded that women with resolved AUD who had received treatment had high scores on the KSP-scales measuring psychic and somatic anxiety, tension, irritability, and feelings of guilt. This suggests that personality assessment might be a useful tool in tailoring individual treatment programs for women with AUD. Future studies need to

  4. Fault-related-folding structures and reflection seismic sections. Study by seismic modeling and balanced cross section; Danso ga kaizaisuru shukyoku kozo no keitai to jishin tansa danmen. 2. Seismic modeling oyobi balanced cross section ni yoru study

    Tamagawa, T.; Matsuoka, T. [Japan Petroleum Exploration Corp., Tokyo (Japan); Tsukui, R. [Japan National Oil Corp., Tokyo (Japan). Technology Research Center


    It occasionally happens that there exists a part where reflection near the thrust is not clearly observed in a thrust zone seismic survey cross section. For the effective interpretation of such an occurrence, the use of geological structures as well as the reflected pattern is effective. When the velocity structures for a fold structure having a listric fault caused anticline (unidirectionally inclined with a backlimb, without a forelimb) and for a fault propagation fold are involved, a wrong interpretation may be made since they look alike in reflection wave pattern despite their difference in geological structure. In the concept of balanced cross section, a check is performed, when the stratum after deformation is recovered to the time of deposition, as to whether the geologic stratum area is conserved without excess or shortage. An excess or shortage occurs if there is an error in the model, and this shows that the fault surface or fold structure is not correctly reflected. Positive application of geological knowledge is required in the processing and interpreting of data from a seismic survey. 6 refs., 6 figs.

  5. Active fault and other geological studies for seismic assessment: present state and problems

    Kakimi, Toshihiro [Nuclear Power Engineering Corp., Tokyo (Japan)


    Evaluation system of earthquakes from an active fault is, in Japan, based on the characteristic earthquake model of a wide sense that postulates essentially the same (nearly the maximum) magnitude and recurrence interval during the recent geological times. Earthquake magnitude M is estimated by empirical relations among M, surface rupture length L, and surface fault displacement D per event of the earthquake faults on land in Japan. Recurrence interval R of faulting/earthquake is calculated from D and the long-term slip rate S of a fault as R=D/S. Grouping or segmentation of complicatedly distributed faults is an important, but difficult problem in order to distinguish a seismogenic fault unit corresponding to an individual characteristic earthquake. If the time t of the latest event is obtained, the `cautiousness` of a fault can be judged from R-t or t/R. According to this idea, several faults whose t/R exceed 0.5 have been designated as the `precaution faults` having higher probability of earthquake occurrence than the others. A part of above evaluation has been introduced at first into the seismic-safety examination system of NPPs in 1978. According to the progress of research on active faults, the weight of interest in respect to the seismic hazard assessment shifted gradually from the historic data to the fault data. Most of recent seismic hazard maps have been prepared in consideration with active faults on land in Japan. Since the occurrence of the 1995 Hyogoken-Nanbu earthquake, social attention has been concentrated upon the seismic hazard due to active faults, because this event was generated from a well-known active fault zone that had been warned as a `precaution fault`. In this paper, a few recent topics on other geological and geotechnical researches aiming at improving the seismic safety of NPPs in Japan were also introduced. (J.P.N.)

  6. Chemical Processes with Supercritical CO2 in Engineered Geologic Systems: Significance, Previous Study, and Path Forward (Invited)

    Xu, T.; Pruess, K.


    Chemical reactions with dissolved CO2 in the aqueous phase have long been considered in fundamental geosciences and practical applications. Recently, studies on geologic carbon sequestration and enhanced geothermal systems using CO2 as heat transmission fluid have brought new interests in chemical reaction processes directly with supercritical CO2 (scCO2, or gas phase). In the vicinity of a CO2 injection well, the aqueous fluid initially present in a geological formation would be quickly removed by dissolution (evaporation) into the flowing gas stream and by immiscible displacement by the scCO2, creating a gas phase dominant zone. In this zone, the water evaporation could cause formation dry-out and precipitation of salt near the injection well, reducing formation porosity, permeability, and injectivity. The scCO2 may directly attack well construction materials such as cement. Over time, the gas phase will tend to migrate upwards towards the caprock because the density of the scCO2 is lower than that of the aqueous phase. In the upper portions of the reservoir, the scCO2 will directly react with caprock minerals and alter the hydrological properties and mechanical strength. On the other hand, the scCO2 phase will maintain the dissolution into the aqueous phase, lowering pH, inducing mineral dissolution, complexing with dissolved cations, increasing CO2 solubility, increasing the density of the aqueous phase, and promoting “convective mixing”. Chemical processes are quite different in the scCO2 dominant geologic systems. The absence of an aqueous phase poses unique questions, as little is presently known about the chemistry of non-aqueous systems. Additional issues arise from the reactivity of water that is dissolved in the ScCO2 phase. In this presentation, the author will discuss the importance, state of the studies performed, and future research directions.

  7. Warfarin dosing after bariatric surgery: a retrospective study of 10 patients previously stable on chronic warfarin therapy.

    Schullo-Feulner, A M; Stoecker, Z; Brown, G A; Schneider, J; Jones, T A; Burnett, B


    Many changes associated with bariatric surgery have the potential to affect warfarin dosing; yet current literature includes little data describing this phenomenon. Investigating this relationship may allow for determination of post-bariatric surgery warfarin dosing using stable pre-operative dosing levels. A retrospective chart review was completed for 10 patients stabilized on chronic warfarin therapy who underwent bariatric surgery. Data collection consisted of the following: warfarin requirement in mg/week, time in target range (TTR), creatinine, liver function, diarrhoea, medication changes, diet, and signs of bleeding and/or thrombosis. Three study patients underwent laparoscopic adjustable gastric banding procedures and seven patients underwent Roux-en-Y gastric bypass. The average (standard deviation) weekly warfarin dose required in the immediate post-operative interval was 64% (25%) of baseline dosing, corresponding to a TTR of 48%. At 6 months, patients required 85% (19%) of baseline weekly dosing, with TTR of 53.4%. At 1 year, dosing was 90% (16%) of baseline with TTR of 63.5%. Patients underwent medication changes as well as transient bouts of diarrhoea. Two patients suffered unspecified haemorrhages of the gastrointestinal tract (international normalized ratio [INR] = 2.3 and 9.8). This patient set demonstrated an initial drop in warfarin requirement, followed by escalating dosing trends that became more predictable as patients were farther out from procedure.

  8. Monofractal or multifractal: a case study of spatial distribution of mining-induced seismic activity

    M. Eneva


    Full Text Available Using finite data sets and limited size of study volumes may result in significant spurious effects when estimating the scaling properties of various physical processes. These effects are examined with an example featuring the spatial distribution of induced seismic activity in Creighton Mine (northern Ontario, Canada. The events studied in the present work occurred during a three-month period, March-May 1992, within a volume of approximate size 400 x 400 x 180 m3. Two sets of microearthquake locations are studied: Data Set 1 (14,338 events and Data Set 2 (1654 events. Data Set 1 includes the more accurately located events and amounts to about 30 per cent of all recorded data. Data Set 2 represents a portion of the first data set that is formed by the most accurately located and the strongest microearthquakes. The spatial distribution of events in the two data sets is examined for scaling behaviour using the method of generalized correlation integrals featuring various moments q. From these, generalized correlation dimensions are estimated using the slope method. Similar estimates are made for randomly generated point sets using the same numbers of events and the same study volumes as for the real data. Uniform and monofractal random distributions are used for these simulations. In addition, samples from the real data are randomly extracted and the dimension spectra for these are examined as well. The spectra for the uniform and monofractal random generations show spurious multifractality due only to the use of finite numbers of data points and limited size of study volume. Comparing these with the spectra of dimensions for Data Set 1 and Data Set 2 allows us to estimate the bias likely to be present in the estimates for the real data. The strong multifractality suggested by the spectrum for Data Set 2 appears to be largely spurious; the spatial distribution, while different from uniform, could originate from a monofractal process. The spatial


    Kevin M. Kostelnik; James H. Clarke; Jerry L. Harbour


    Environmental remediation efforts that are underway at hundreds of contaminated sites in the United States will not be able to remediate large portions of those sites to conditions that would permit unrestricted access. Rather, large volumes of waste materials, contaminated soils and cleanup residuals will have to be isolated either in place or in new, often on-site, disposal cells with long term monitoring, maintenance and institutional control needs. The challenge continues to be to provide engineering systems and controls that can ensure the protection of public health and the environment over very long time horizons (hundreds to perhaps thousands of years) with minimal intervention. Effective long term management of legacy hazardous and nuclear waste requires an integrated approach that addresses both the engineered containment and control system itself and the institutional controls and other responsibilities that are needed. Decisions concerning system design, monitoring and maintenance, and the institutional controls that will be employed are best done through a "risk-nformed, performance-based" approach. Such an approach should incorporate an analysis of potential "failure" modes and consequences for all important system features, together with lessons learned from experience with systems already in place. The authors will present the preliminary results of a case study approach that included several sites where contamination isolation systems including institutional controls have been implemented. The results are being used together with failure trees and logic diagrams that have been developed for both the engineered barriers and the institutional controls. The use of these analytical tools to evaluate the potential for different levels of failure and associated consequences will be discussed. Of special interest is the robustness of different approaches to providing long-term protection through redundancy and defense in depth.

  10. Variations of the accessory nerve: anatomical study including previously undocumented findings-expanding our misunderstanding of this nerve.

    Tubbs, R Shane; Ajayi, Olaide O; Fries, Fabian N; Spinner, Robert J; Oskouian, Rod J


    The anatomy of the accessory nerve has been well described but continued new clinical and anatomical findings exemplify our lack of a full understanding of the course of this nerve. Therefore, this study aimed to expand on our knowledge of the course of the 11th cranial nerve via anatomical dissections. Fifty-six cadavers (112 sides) underwent dissection of the accessory nerve from its cranial and spinal origins to its emergence into the posterior cervical triangle. Immunohistochemistry was performed when appropriate. Our findings included two cases (1.8%) where the nerve was duplicated, one intracranially and one extracranially. One accessory nerve (0.9%) was found to enter its own dural compartment within the jugular foramen. The majority of sides (80%) were found to have a cranial root of the accessory nerve. Thirty-one sides (28%) had connections to cervical dorsal roots medially and three sides (2.7%) laterally. Medial connections were most common with the C1 nerve. Medial components of these dorsal root connections were all sensory in nature. However, lateral components were motor on two sides (1.8%). Nerves traveled anterior to the internal jugular vein on 88% of sides. One (0.9%) left side nerve joined an interneural anastomosis between the dorsal rootlets. Macroganglia were found on the spinal part of the intracranial nerve on 13% of sides. The lesser occipital nerve arose directly from the accessory nerve on two sides (1.8%) and communicated with the accessory nerve on 5.4% of sides. One side (0.9%) was found to communicate with the facial nerve with both nerves innervating the sternocleidomastoid muscle. Additional anatomical knowledge of the variants of the accessory nerve may benefit patient care when this nerve is pathologically involved.

  11. 2D Seismic Data Processing for Straight Lines in the Loess Plateaus in Fuxian of Shanbei

    LiMinjie; ChenYequan; ZhangHai; PangShangming; DengGuozhen


    The crooked seismic lines along valleys were irregular previously in Fuxian of Shanbei,showing an irregular branch in plane, and hard to complete close grids. Therefore, it's difficult to conduct reservoir inversion of 2D seismic data. In 2001, Zhongyuan Oilfield Company carried out the study on field acquisition methods and seismic processing technology in Fuxian. Straight lines were passing through plateaus and formed seismic grids by using flexible geometry with variable linear bins.Data processing involved model-inversion based refraction static correction, surface consistent amplitude compensation, deconvolution, and pre-stack noise attenuation. As the result, seismic data with a high fidelity was provided for the subsequent reservoir predictions, small-amplitude structure interpretation and integrative geologic study. Because all lines were jointed to form grids, comprehensive interpretation of reservoir inversion could be finally implemented by using the pseudo logging method to control lines without wells.

  12. Study on the applicability of the microtremor HVSR method to support seismic microzonation in the town of Idrija (W Slovenia

    A. Gosar


    Full Text Available The town of Idrija is located in an area with an increased seismic hazard in W Slovenia and is partly built on alluvial sediments or artificial mining and smelting deposits which can amplify seismic ground motion. There is a need to prepare a comprehensive seismic microzonation in the near future to support seismic hazard and risk assessment. To study the applicability of the microtremor horizontal-to-vertical spectral ratio (HVSR method for this purpose, 70 free-field microtremor measurements were performed in a town area of 0.8 km2 with 50–200 m spacing between the points. The HVSR analysis has shown that it is possible to derive the sediments' resonance frequency at 48 points. With the remaining one third of the measurements, nearly flat HVSR curves were obtained, indicating a small or negligible impedance contrast with the seismological bedrock. The isofrequency (a range of 2.5–19.5 Hz and the HVSR peak amplitude (a range of 3–6, with a few larger values maps were prepared using the natural neighbor interpolation algorithm and compared with the geological map and the map of artificial deposits. Surprisingly no clear correlation was found between the distribution of resonance frequencies or peak amplitudes and the known extent of the supposed soft sediments or deposits. This can be explained by relatively well-compacted and rather stiff deposits and the complex geometry of sedimentary bodies. However, at several individual locations it was possible to correlate the shape and amplitude of the HVSR curve with the known geological structure and prominent site effects were established in different places. In given conditions (very limited free space and a high level of noise it would be difficult to perform an active seismic refraction or MASW measurements to investigate the S-wave velocity profiles and the thickness of sediments in detail, which would be representative enough for microzonation purposes. The importance of the

  13. Study on the applicability of the microtremor HVSR method to support seismic microzonation in the town of Idrija (W Slovenia)

    Gosar, Andrej


    The town of Idrija is located in an area with an increased seismic hazard in W Slovenia and is partly built on alluvial sediments or artificial mining and smelting deposits which can amplify seismic ground motion. There is a need to prepare a comprehensive seismic microzonation in the near future to support seismic hazard and risk assessment. To study the applicability of the microtremor horizontal-to-vertical spectral ratio (HVSR) method for this purpose, 70 free-field microtremor measurements were performed in a town area of 0.8 km2 with 50-200 m spacing between the points. The HVSR analysis has shown that it is possible to derive the sediments' resonance frequency at 48 points. With the remaining one third of the measurements, nearly flat HVSR curves were obtained, indicating a small or negligible impedance contrast with the seismological bedrock. The isofrequency (a range of 2.5-19.5 Hz) and the HVSR peak amplitude (a range of 3-6, with a few larger values) maps were prepared using the natural neighbor interpolation algorithm and compared with the geological map and the map of artificial deposits. Surprisingly no clear correlation was found between the distribution of resonance frequencies or peak amplitudes and the known extent of the supposed soft sediments or deposits. This can be explained by relatively well-compacted and rather stiff deposits and the complex geometry of sedimentary bodies. However, at several individual locations it was possible to correlate the shape and amplitude of the HVSR curve with the known geological structure and prominent site effects were established in different places. In given conditions (very limited free space and a high level of noise) it would be difficult to perform an active seismic refraction or MASW measurements to investigate the S-wave velocity profiles and the thickness of sediments in detail, which would be representative enough for microzonation purposes. The importance of the microtremor method is therefore even

  14. Modelling study of challenges in sinkhole detection with shear wave reflection seismics

    Burschil, Thomas; Krawczyk, CharLotte M.


    The detection of cavities with reflection seismics is a difficult task even if high impedance contrasts are assumed. Especially the shear wave reflection method with a higher resolution potential trough lower velocities and short wavelength has come into focus of investigation. But shear wave propagation fails if material exists that partially has no shear strength. The shear wave does not propagate into or through those voids. Here, we evaluate the influence of a possible fracture zone above a cavity. We simulate shear wave propagation with finite difference modelling for two reference models, with and without cavity, and various sets of input models with a fracture zone above the cavity. Reflections and multiples of the reference models image the subsidence structure and the cavity. For the fracture input models, we implemented a fracture network, derived from numerical crack propagation modelling (Schneider-Löbens et al., 2015). The cracks possess the minimum possible aperture of one grid point (i.e. 0.1 m) and no shear stiffness. The seismic modelling exhibits that the shear wave does not pass through the fracture zone and shadows the subjacent cavity. Sequences of randomly discontinuous cracks, cf. displacement discontinuity model with zero crack stiffness, approximate partially seismic connected rock on both sides of the crack. The amount of these seismic pathways determines whether a reflection of the cavity can be detected at the surface or not. Cracks with higher aperture, e.g. two or three grid points, need a higher amount of intact rock/defective cracks, since more connected grid points are necessary to create seismic pathways. Furthermore, it turns out that the crack filling is important for shear wave transmission. While a mineralized fracture zone, implemented with high velocity, facilitate shear wave propagation, water or air-filled cracks avoid shear wave transmission. Crack orientation affects the shear wave propagation through the geometry. A

  15. A Study on Seismic Hazard Evaluation at the Nagaoka CO2 Storage Site, Japan

    Horikawa, S.


    RITE carried out the first Japanese pilot-scale CO2 sequestration project from July, 2003 to January, 2005 in Nagaoka City.Supercritical CO2 was injected into an onshore saline aquifer at a depth of 1,100m. CO2 was injected at a rate of 10,400 tonnes. 'Mid Niigata Prefecture Earthquake in 2004' (Mw6.6) and 'The Niigataken Chuetsu-oki Earthquake in 2007' (Mw6.6) occurred during the CO2 injection-test and after the completion of injection-test. Japan is one of the world's major countries with frequent earthquakes.This paper presents a result of seismic response analysis, and reports of seismic hazard evaluation of a reservoir and a caprock. In advance of dynamic response analysis, the earthquake motion recorded on the earth surface assumed the horizontally layer model, and set up the input wave from a basement layer by SHAKE ( = One-Dimensional Seismic Response Analysis). This wave was inputted into the analysis model and the equation of motion was solved using the direct integral calculus by Newmark Beta Method. In Seismic Response Analysis, authors have used Multiple Yield Model (MYM, Iwata, et al., 2013), which can respond also to complicated geological structure. The intensity deformation property of the foundation added the offloading characteristic to the composition rule of Duncan-Chang model in consideration of confining stress dependency, and used for and carried out the nonlinear repetition model. And the deformation characteristic which made it depend on confining stress with the cyclic loadings and un-loadings, and combined Mohr-Coulomb's law as a strength characteristic.The maximum dynamic shearing strain of caprock was generated about 1.1E-04 after the end of an earthquake. Although the dynamic safety factor was 1.925 on the beginning, after the end of an earthquake fell 0.05 point. The dynamic safety factor of reservoir fell to 1.20 from 1.29. As a result of CO2 migration monitoring by the seismic cross-hole tomography, CO2 has stopped in the reservoir

  16. Seismicity in Pennsylvania: Evidence for Anthropogenic Events?

    Homman, K.; Nyblade, A.


    The deployment and operation of the USArray Transportable Array (TA) and the PASEIS (XY) seismic networks in Pennsylvania during 2013 and 2014 provide a unique opportunity for investigating the seismicity of Pennsylvania. These networks, along with several permanent stations in Pennsylvania, resulted in a total of 104 seismometers in and around Pennsylvania that have been used in this study. Event locations were first obtained with Antelope Environmental Monitoring Software using P-wave arrival times. Arrival times were hand picked using a 1-5 Hz bandpass filter to within 0.1 seconds. Events were then relocated using a velocity model developed for Pennsylvania and the HYPOELLIPSE location code. In this study, 1593 seismic events occurred between February 2013 and December 2014 in Pennsylvania. These events ranged between magnitude (ML) 1.04 and 2.89 with an average MLof 1.90. Locations of the events occur across the state in many areas where no seismicity has been previously reported. Preliminary results indicate that most of these events are related to mining activity. Additional work using cross-correlation techniques is underway to examine a number of event clusters for evidence of hydraulic fracturing or wastewater injection sources.

  17. Improving Seismic Image with Advanced Processing Techniques

    Mericy Lastra Cunill


    Full Text Available Taking Taking into account the need to improve the seismic image in the central area of Cuba, specifically in the area of the Venegas sector, located in the Cuban Folded Belt, the seismic data acquired by Cuba Petróleo (CUPET in the year 2007 was reprocessed according to the experience accumulated during the previous processing carried out in the same year, and the new geologic knowledge on the area. This was done with the objective of improving the results. The processing applied previously was analyzed by reprocessing the primary data with new focuses and procedures, among them are the following: the attenuation of the superficial wave with a filter in the Radon domain in its lineal variant, the change of the primary statics corrections of elevation by those of refraction, the study of velocity with the selection automatic biespectral of high density, the study of the anisotropy, the attenuation of the random noise, and the pre stack time and depth migration. As a result of this reprocessing, a structure that was not identified in the seismic sections of the previous processing was located at the top of a Continental Margin sediment located to the north of the sector that increased the potentialities of finding hydrocarbons in quantities of economic importance thus diminishing the risk of drilling in the sector Venegas.

  18. Integrating sequence stratigraphy and seismic attributes for quantitative reservoir characterization: A case study of a Pliocene reservoir, Campeche Sound, Mexico

    Mendez-Hernandez, Efrain

    geology of Mexico and the Gulf of Mexico basin. It confirms the petroleum system for this Pliocene play, proposes a new play concept and provides the basis for further research in the study area. Future work is recommended to extend the regional geological mapping using the integrated methodology and play analysis developed from this dissertation. New well and seismic data focused on Neogene levels should also be obtained to improve the knowledge and assure expectations for future exploration and development strategies in these and other subtle stratigraphic gas traps of this traditional oil province.

  19. Broadband seismic effects from train vibrations

    Fuchs, Florian; Bokelmann, Götz


    Seismologists rarely study train induced vibrations which are mainly regarded an unwanted source of noise for classical seismological applications such as earthquake monitoring. A few seismological studies try to utilize train vibrations however as active sources, e.g. for subsurface imaging, but they do not focus on the characteristics of the train signal itself. Most available studies on train induced vibrations take an engineering approach and aim at better understanding the generation and short-distance propagation of train induced vibrations, mainly for mitigation and construction purposes. They mostly rely on numerical simulations and/or short-period or accelerometer recordings obtained directly on the train track or up to few hundred meters away and almost no studies exist with seismic recordings further away from the track. In some of these previous studies sharp and equidistant peaks are present in the vibration spectrum of heavy freight trains, but they do not attempt to explain them. Here we show and analyze various train vibration signals obtained from a set of seismic broadband stations installed in the context of the temporary, large-scale regional seismic network AlpArray. The geometrical restrictions of this seismic network combined with budget and safety considerations resulted in a number of broad-band instruments deployed in the vicinity of busy railway lines. On these stations we observe very characteristic seismic signals associated with different types of trains, typically showing pronounced equidistant spectral lines over a wide frequency range. In this study we analyze the nature of such signals and discuss if they are generated by a source effect or by wave propagation effects in near-surface soil layers.

  20. Study on the physical meaning of seismic inhomogeneous degree by rock fracture experiments

    LI Zhi-xiong; MA Sheng-li; LI Sheng-qiang; LI Min-feng; LU Peng; CHEN Hua-jing; WANG Song; WU Ting


    It is observed that the parameter of seismic inhomogeneous degree (GL value) calculated from the earthquake catalog shows obvious abnormal changes prior to strong earthquakes, indicating the state change of local seismic activity. This paper focuses on the mechanism for the abnormal changes of the GL values based on the sequences of acoustic emission for three types of rock samples containing macro-asperity fracture; compressional en-echelon fracture and model-III shear fracture. The results show that for the three types of rock samples, there are continuous abnormal changes of GL value (>1) just before the non-elastic deformation occurs or during the process of nucleation prior to the instability. Based on the experimental results, it seems that the process of creep sliding and resistance-uniformization along fault zone is the possible mechanism for the abnormal changes of GL value before rock fractures.

  1. A comparative study of two models for the seismic analysis of buildings

    Arnulfo Luévanos Rojas


    Full Text Available This paper presents a model for the seismic analysis of buildings, taking two lumped masses at each level in a structure’s free nodes and comparing them to the traditional model which considers lumped masses per level, i.e., a mass for each floor of the entire building. This  is usually done in the seismic analysis of buildings; not all values are conservative in the latter, as can be seen in the table of results. Both models took shear deformations into account. Therefore, the usual practice of considering a lumped mass per each level would not be a recommended solution; using two lumped masses per level is thus proposed and is also more related to real conditions.

  2. Enhancement in Seismic Imaging using Diffraction Studies and Hybrid Traveltime Technique for PSDM

    Bashir, Y.; Ghosh, D. P.; Moussavi Alashloo, S. Y.; Sum, C. W.


    The accurate migration of seismic data is conditional on the parameters which are nominated. The effective velocity used in residual processing for migration is small compared to the original migration velocity. Considering traveltime computation is a significant part of seismic imaging algorithms. Conventional implementation of Kirchhoff migration is essential for precomputing a traveltime table from the categories involving traditional ray-tracing methods and finite difference eikonal solvers. In this paper, we examine the accuracy using, the eikonal solver and paraxial ray tracing traveltime computation in pre-stack Kirchhoff depth migration. This hybrid traveltime technique can be applied to a variety of problems related to faults, fractures, and complex region. To evaluate the relevance of this identical traveltime technique, we applied on a Marmousi data set.

  3. Seismic criteria studies and analyses. Quarterly progress report No. 3. [LMFBR


    Information is presented concerning the extent to which vibratory motions at the subsurface foundation level might differ from motions at the ground surface and the effects of the various subsurface materials on the overall Clinch River Breeder Reactor site response; seismic analyses of LMFBR type reactors to establish analytical procedures for predicting structure stresses and deformations; and aspects of the current technology regarding the representation of energy losses in nuclear power plants as equivalent viscous damping.

  4. Toward High Precision Seismic Studies of White Dwarf Stars: Parametrization of the Core and Tests of Accuracy

    Giammichele, N; Fontaine, G; Brassard, P


    We present a prescription for parametrizing the chemical profile in the core of white dwarfs in the light of the recent discovery that pulsation modes may sometimes be deeply confined in some cool pulsating white dwarfs. Such modes may be used as unique probes of the complicated chemical stratification that results from several processes that occurred in previous evolutionary phases of intermediate-mass stars. This effort is part of our ongoing quest for more credible and realistic seismic models of white dwarfs using static, parametrized equilibrium structures. Inspired from successful techniques developed in design optimization fields (such as aerodynamics), we exploit Akima splines for the tracing of the chemical profile of oxygen (carbon) in the core of a white dwarf model. A series of tests are then presented to better seize the precision and significance of the results that can be obtained in an asteroseismological context. We also show that the new parametrization passes an essential basic test, as it ...

  5. Crustal Seismicity and Recent Faults in Southern Peru

    David, C.; Comte, D.; Tavera, H.; Audin, L.; Herail, G.


    Most seismological studies in southern Peru have been focused on the downgoing slab seismicity in order to constrain the Wadati-Benioff zone. This study deals with the intra-continental seismicity of the southern Peru forearc (17,3° S - 18,5° S) in a post-seismic context (Arequipa thrust earthquake, Mw=8.4, 23 June, 2001). It is difficult to identify historical crustal earthquake from available catalogues, however some crustal events teleseismically recorded can be found since 1976; they exhibit normal focal mechanism solutions in the southern Peru volcanic arc and inverse focal mechanism solutions in the Central Depression. Following a notable increase of shallow crustal seismicity located close to the Western Cordillera after the 23 June 2001, a temporary seismic network was deployed between January and March 2003 in order to study the Wadati-Benioff zone and monitoring the crustal seismicity in southern Peru. From the about 1700 events locally recorded by the local network, 300 crustal earthquakes were identified in the Peruvian forearc between Tacna and Moquegua. This crustal seismicity is distributed along a lineament located at depths between 0 and 60 km, dipping at about 45° from the Western Cordillera towards the coast, almost perpendicular to the subducting slab; this behaviour was previously observed in northern Chile and in southern Peru, north of the study zone (16° S). In the Central Depression, seismic activity is not superficial occurring between 25-60 km depth and it is mostly characterized by inverse focal mechanism solutions. Superficial faults situated in the Central Depression and in the Coastal Cordillera can not be associated with the seismic activity observed in this area. However, in the Pre-Cordillera, crustal seismicity occurs at depths between 0-15 km and can be correlated with shallow fault systems recognized by satellite images and on the field. For examples, the Incapuquio fault system which was a transpressive system in Cretaceous

  6. Passive seismic monitoring of landslides' creep: Case studies at Super-Sauze (Southeastern France) and Pechgraben (Upper Austria) clay-rich landslides

    Vouillamoz, Naomi; Rothmund, Sabrina; Joswig, Manfred; Malet, Jean-Philippe; Jochum, Birgit


    Landslides developed in clay-rich formations are characterized by unpredictable reactivation. In recent years, seismic monitoring of active landslides detected a variety of - generally weak - seismic signals triggered by the unstable slope. Evaluating landslide seismicity and characterizing its occurrence in space and time enable thus to monitor and map dynamics of the landslide in near real-time. Passive seismic monitoring appears therefore as a promising approach to complement surveillance and early warning systems of active landslides. However, extreme scattering of the waveforms in the heterogeneous material composing the slopes combined to the inherent difficulty of operating seismic networks with optimal geometry in rugged terrains severely challenge standard approaches to event location and consequently impedes source processes interpretation. In this study, we investigate continuous seismic sonograms of the well-instrumented Super-Sauze landslide (Southeastern France) and compare observations with newly acquired seismic data at the Pechgraben landslide (Upper Austria). Despite varying displacement rates (mm.d-1 - cm.d-1) and hydrological conditions, comparable signals that range from impulsive earthquake-like signals to minute-long tremor sequences are detected at both landslides. In addition to beam forming methods, we use waveform attenuation patterns to evaluate the signal source location. Source sizing is then benchmarked with calibration shots carried out at the two landslides. First results indicate that endogenous seismicity rates correlate positively with higher displacement rates and that signals seem to be preferentially originated close to shearing boundaries at the edge or within the slides. Using these arguments we suggest creeping processes as potential signal source origin for the observed signals.

  7. Seismic hazards in Thailand: a compilation and updated probabilistic analysis

    Pailoplee, Santi; Charusiri, Punya


    A probabilistic seismic hazard analysis (PSHA) for Thailand was performed and compared to those of previous works. This PSHA was based upon (1) the most up-to-date paleoseismological data (slip rates), (2) the seismic source zones, (3) the seismicity parameters ( a and b values), and (4) the strong ground-motion attenuation models suggested as being suitable models for Thailand. For the PSHA mapping, both the ground shaking and probability of exceedance (POE) were analyzed and mapped using various methods of presentation. In addition, site-specific PSHAs were demonstrated for ten major provinces within Thailand. For instance, a 2 and 10 % POE in the next 50 years of a 0.1-0.4 g and 0.1-0.2 g ground shaking, respectively, was found for western Thailand, defining this area as the most earthquake-prone region evaluated in Thailand. In a comparison between the ten selected specific provinces within Thailand, the Kanchanaburi and Tak provinces had comparatively high seismic hazards, and therefore, effective mitigation plans for these areas should be made. Although Bangkok was defined as being within a low seismic hazard in this PSHA, a further study of seismic wave amplification due to the soft soil beneath Bangkok is required.

  8. Study the Effectiveof Seismic load on Behavior of Shear Wall in Frame Structure

    Dr.Hadi Hosseini


    Full Text Available Structural walls, or shear walls, are elements used to resist lateral loads, such as those generated by wind and earthquakes. Structural walls are considerably deeper than typical beams or columns. This attribute gives structural walls considerable in-plane stiffness which makes structural walls a natural choice for resisting lateral loads. In addition to considerable strength, structural walls can dissipate a great deal of energy if detailed properly. Walls are an invaluable structural element when protecting buildings from seismic events. Buildings often rely on structural walls as the main lateral force resisting system. Shear walls are required to perform in multiple ways. Shear walls can then be designed to limit building damage to the specified degree. The load-deformation response of the structural walls must be accurately predicted and related to structural damage in order to achieve these performance goals under loading events of various magnitudes. The applied load is generally transferred to the wall by a diaphragm or collector or drag member. The performance of the framed buildings depends on the structural system adopted for the structure The term structural system or structural frame in structural engineering refers to load-resisting sub-system of a structure. The structural system transfers loads through interconnected structural components or members. These structural systems need to be chosen based on its height and loads and need to be carried out, etc. The selection of appropriate structural systems for building must satisfy both strength and stiffness requirements. The structural system must be adequate to resist lateral and gravity loads that cause horizontal shear deformation and overturning deformation. The efficiency of a structural system is measured in terms of their ability to resist lateral load, which increases with the height of the frame. A building can be considered as tall when the effect of lateral loads is

  9. Characterizing an unconventional reservoir with conventional seismic data: A case study using seismic inversion for the Vaca Muerta Formation, Neuquen Basin, Argentina

    Fernandez-Concheso, Jorge E.

    Reservoir characterization for unconventional shale plays ideally requires multi-component, wide-azimuth, long-offset surface seismic data. These data are generally not available, especially in exploration or pre-development stages. Furthermore, it is common to have only a few wells over a large area, along with non-existent or scarce microseismic, engineering and production data. This thesis presents a methodology and workflow to deal with these circumstances of limited data availability. By using a narrow-azimuth, regional P-wave seismic volume and integrating it with wireline logs, cuttings and PLT data, the variability in the geomechanical properties of the Vaca Muerta Formation in Argentina's Neuquen Basin, and their relationships with lithology, stress state and total organic content, were analyzed. Post-stack and pre-stack inversions were performed on the seismic volume. The un- certainties inherent from limited well control in the estimation of elastic properties were investigated using blind well testing. Sensitivity and error analysis was conducted on post-stack vs pre-stack derived P-impedance, the choice of the inversion algorithm (model-based vs sparse-spike) and the definition of the low frequency model (simple kriging model vs complex model derived from multi-attribute stepwise regression) were examined. Also, the use of isotropic AVA equations to approximate the anisotropic (VTI) behaviour of the reservoir was evaluated, using estimates of Thomsen parameters and simple AVA modelling. The integration of the inversion results with the petrophysical analysis and the mechanical stratigraphy work by Bishop (2015), suggests that the rock composition has the largest influence on the geomechanical behaviour of the reservoir. Overpressure is also a major driving factor in that it controls changes in elastic properties. Bishop's cluster analysis was used to identify good quality rock classes. The probabilistic interpretation of these rock classes from seismic

  10. Interactive web visualization tools to the results interpretation of a seismic risk study aimed at the emergency levels definition

    Rivas-Medina, A.; Gutierrez, V.; Gaspar-Escribano, J. M.; Benito, B.


    Results of a seismic risk assessment study are often applied and interpreted by users unspecialised on the topic or lacking a scientific background. In this context, the availability of tools that help translating essentially scientific contents to broader audiences (such as decision makers or civil defence officials) as well as representing and managing results in a user-friendly fashion, are on indubitable value. On of such tools is the visualization tool VISOR-RISNA, a web tool developed within the RISNA project (financed by the Emergency Agency of Navarre, Spain) for regional seismic risk assessment of Navarre and the subsequent development of emergency plans. The RISNA study included seismic hazard evaluation, geotechnical characterization of soils, incorporation of site effects to expected ground motions, vulnerability distribution assessment and estimation of expected damage distributions for a 10% probability of exceedance in 50 years. The main goal of RISNA was the identification of higher risk area where focusing detailed, local-scale risk studies in the future and the corresponding urban emergency plans. A geographic information system was used to combine different information layers, generate tables of results and represent maps with partial and final results. The visualization tool VISOR-RISNA is intended to facilitate the interpretation and representation of the collection of results, with the ultimate purpose of defining actuation plans. A number of criteria for defining actuation priorities are proposed in this work. They are based on combinations of risk parameters resulting from the risk study (such as expected ground motion and damage and exposed population), as determined by risk assessment specialists. Although the values that these parameters take are a result of the risk study, their distribution in several classes depends on the intervals defined by decision takers or civil defense officials. These criteria provide a ranking of

  11. A study on the seismic AVO signatures of deep fractured geothermal reservoirs in an intrusive basement.

    Aleardi, M.; Mazzotti, A.


    Amplitude-variation-with-offset (AVO) analysis of reflected waves has become an important tool for hydrocarbon prospecting. However, while the AVO responses of reservoirs in clastic lithologies (oil or gas bearing sands) are well known, the AVO behaviour of reservoirs hosted in the interconnected fractures of massive rocks are almost unknown due to the rarity of this type of reservoirs and the consequent lack of seismic and well log data. Thanks to the availability of the data of boreholes that ENEL GreenPower drilled in the deep intrusive basement of the Larderello-Travale geothermal field, we have derived the expected AVO responses of the vapour reservoirs found in some intensely, but very localized, fractured volumes within the massive rocks. Therefore we wish to determine what are the expected AVO responses of geothermal reservoirs inside fractured igneous rocks and we seek to find one or more AVO attributes that may help identifying fracture locations. To this end, we have analysed the velocity (P-wave and S-wave) and the density logs pertaining to three wells which reached five deep fractured zones in the basement. However, comparing well log data with surface seismic data the known issues of the different scales and thus different resolutions arise. Therefore, making use of the Backus theory of the equivalent layer, we have downscaled the well logs, acquired at a decimetric scale, to a decametric scale typical of the wavelengths of seismic waves, producing a blocky model of the original logs. Subsequently, we have followed two different approaches to estimate the expected responses. First, on the basis of the P and S velocities and densities of the fractured level and of the encasing rock, we have computed the analytical AVO response of each fractured zone. To this end we have made use of the linear Shuey equation that well describes the AVO response up to incident angles of 30 degrees. This would be the theoretical, noise free, response that perfectly

  12. Perception of seismic risk in the new Anthropocene geological era. A comparison between two case-studies: Calabria (South Italy) and Malta

    De Pascale, Francesco; Bernardo, Marcello; Muto, Francesco; D'Amico, Sebastiano; Zumbo, Rosarianna; Galea, Pauline; Agius, Matthew


    About two centuries ago, the Earth entered the Anthropocene, a new geological epoch in which man has a marked impact on climate and the environment. In comparison with the slow passing of previous millennia, our species has, in a very short time, radically altered the world's ecosystems. For some years now, interest in Italy has been increasing in Geoethics and the ethical, sociological and cultural implications of Earth Sciences. This involves amplifying the prospects and expectations of Geosciences and highlighting the fundamental role of geological and geographical studies in finding solutions to the practical problems that man faces which are also compatible with the preservation of nature and the planet. Indeed, man can even be an active participant in natural catastrophes in the sense that he is able to amplify the damage and natural dynamics. On the other hand, as much as these phenomena can only be foreseen to a limited extent, intervention is possible with regards the parameters of risk which are dependent upon anthropisation, such as those of vulnerability and exposed value that mark the difference between a natural event and a calamity. Therefore, through information about and knowledge of risk, it is possible to keep damage to a minimum by refining techniques of prevision and prevention. Geographical studies orientated towards examining descriptive natural elements and analysing social behaviour when people are faced with natural risks generated by assumed given and exogenous sources can be historically placed within the area of research into the perception of natural risk. In this context, a questionnaire was given to primary and middle school pupils in an area of Calabria which has recently been affected by an on-going seismic sequence, widely felt by the population. The same questionnaire was given to students in Malta, a zone of low-to-moderate seismic hazard where earthquake awareness is not culturally strong. The Maltese islands have, however

  13. Study on determination of stress level by seismic stress drops and the stress axis deflections before and after large earthquakes

    WAN Yong-ge


    To obtain the stress level at the earthquake source, this paper sets forth the solution of the stress magnitude at the earthquake source by seismic stress drop and the stress axis deflections before and after large earthquakes. The pre-seismic and post-seismic stress direction can be statistically determined by a large collection of foreshock and aftershock focal mechanism data while the stress drop can be determined through the source fracture inversion from seismic wave data or crust deformation data. The paper attempts to make a fundamental contribution to seismic dynamics.

  14. Seismic detectability of meteorite impacts on Europa

    Tsuji, Daisuke; Teanby, Nicholas


    Europa, the second of Jupiter's Galilean satellites, has an icy outer shell, beneath which there is probably liquid water in contact with a rocky core. Europa, may thus provide an example of a sub-surface habitable environment so is an attractive object for future lander missions. In fact, the Jupiter Icy Moon Explorer (JUICE) mission has been selected for the L1 launch slot of ESA's Cosmic Vision science programme with the aim of launching in 2022 to explore Jupiter and its potentially habitable icy moons. One of the best ways to probe icy moon interiors in any future mission will be with a seismic investigation. Previously, the Apollo seismic experiment, installed by astronauts, enhanced our knowledge of the lunar interior. For a recent mission, NASA's 2016 InSight Mars lander aims to obtain seismic data and will deploy a seismometer directly onto Mars' surface. Motivated by these works, in this study we show how many meteorite impacts will be detected using a single seismic station on Europa, which will be useful for planning the next generation of outer solar system missions. To this end, we derive: (1) the current small impact flux on Europa from Jupiter impact rate models; (2) a crater diameter versus impactor energy scaling relation for ice by merging previous experiments and simulations; (3) scaling relations for seismic signals as a function of distance from an impact site for a given crater size based on analogue explosive data obtained on Earth's icy surfaces. Finally, resultant amplitudes are compared to the noise level of a likely seismic instrument (based on the NASA InSight mission seismometers) and the number of detectable impacts are estimated. As a result, 0.5-3.0 local/regional small impacts (i.e., direct P-waves through the ice crust) are expected to be detected per year, while global-scale impact events (i.e., PKP-waves refracted through the mantle) are rare and unlikely to be detected by a short duration mission. We note that our results are

  15. seismic-py: Reading seismic data with Python


    Full Text Available The field of seismic exploration of the Earth has changed
    dramatically over the last half a century. The Society of Exploration
    Geophysicists (SEG has worked to create standards to store the vast
    amounts of seismic data in a way that will be portable across computer
    architectures. However, it has been impossible to predict the needs of the
    immense range of seismic data acquisition systems. As a result, vendors have
    had to bend the rules to accommodate the needs of new instruments and
    experiment types. For low level access to seismic data, there is need for a
    standard open source library to allow access to a wide range of vendor data
    files that can handle all of the variations. A new seismic software package,
    seismic-py, provides an infrastructure for creating and managing drivers for
    each particular format. Drivers can be derived from one of the known formats
    and altered to handle any slight variations. Alternatively drivers can be
    developed from scratch for formats that are very different from any previously
    defined format. Python has been the key to making driver development easy
    and efficient to implement. The goal of seismic-py is to be the base system
    that will power a wide range of experimentation with seismic data and at the
    same time provide clear documentation for the historical record of seismic
    data formats.

  16. An analytical study on excitation of nuclear-coupled thermal-hydraulic instability due to seismically induced resonance in BWR

    Hirano, Masashi [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)


    This paper describes the results of a scoping study on seismically induced resonance of nuclear-coupled thermal-hydraulic instability in BWRs, which was conducted by using TRAC-BF1 within a framework of a point kinetics model. As a result of the analysis, it is shown that a reactivity insertion could occur accompanied by in-surge of coolant into the core resulted from the excitation of the nuclear-coupled instability by the external acceleration. In order to analyze this phenomenon more in detail, it is necessary to couple a thermal-hydraulic code with a three-dimensional nuclear kinetics code.

  17. Study of minima of the fluctuations of the order parameter of seismicity using GCMT catalogue in global scale.

    Christopoulos, Stavros-Richard G.; Sarlis, Nicholas V.; Skordas, Efthimios S.


    It has been recently shown [1,2] that earthquakes of magnitude M greater or equal to 7 are globally correlated. The identification of this correlation became possible when studying the variance κ1 of natural time which has been proposed as an order parameter for seismicity[3,4]. In the present study, we focus on the behaviour of the fluctuations of κ1 before major earthquakes using the Global Centroid Moment Tensor catalogue for a magnitude threshold Mthres=5.0 as in Ref.[5]. Natural time analysis reveals that distinct minima of the fluctuations κ1of seismicity appear within almost five and a half months on average before all major earthquakes of magnitude larger than M8.4. This phenomenon corroborates the recent finding [6] that similar minima of seismicity order parameter fluctuations had been observed before all major shallow earthquakes in Japan. Finally, we examine the statistical significance of the results by using ROC graphs [7,8] and the proposed prediction method has a p-value to occur by chance well below 0.1%. The hit rate is 100% with a false alarm rate only 6.67%. An attempt to lower the target earthquake magnitude threshold will be also presented. REFERENCES [1] N. V. Sarlis, Phys. Rev. E 84, 022101 (2011). [2] N. V. Sarlis and S.-R. G. Christopoulos, Chaos 22, 023123 (2012) [3] P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, Practica of Athens Acad. 76, 294 (2001). [4] P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, Phys. Rev. E 66, 011902 (2002). [5] N.V. Sarlis, S.-R. G. Christopoulos, and E. S. Skordas, Chaos 25, 063110 (2015) [6] N. V. Sarlis et al., Proc. Natl. Acad. Sci. U.S.A. 110, 13734 (2013) [7] T. Fawcett, Pattern Recognit. Lett. 27, 861 (2006). [8] N. V. Sarlis and S.-R. G. Christopoulos, Comput. Phys. Commun. 185, 1172 (2014).

  18. Elastic-Wavefield Seismic Stratigraphy: A New Seismic Imaging Technology

    Bob A. Hardage; Milo M. Backus; Michael V. DeAngelo; Sergey Fomel; Khaled Fouad; Robert J. Graebner; Paul E. Murray; Randy Remington; Diana Sava


    The purpose of our research has been to develop and demonstrate a seismic technology that will provide the oil and gas industry a better methodology for understanding reservoir and seal architectures and for improving interpretations of hydrocarbon systems. Our research goal was to expand the valuable science of seismic stratigraphy beyond the constraints of compressional (P-P) seismic data by using all modes (P-P, P-SV, SH-SH, SV-SV, SV-P) of a seismic elastic wavefield to define depositional sequences and facies. Our objective was to demonstrate that one or more modes of an elastic wavefield may image stratal surfaces across some stratigraphic intervals that are not seen by companion wave modes and thus provide different, but equally valid, information regarding depositional sequences and sedimentary facies within that interval. We use the term elastic wavefield stratigraphy to describe the methodology we use to integrate seismic sequences and seismic facies from all modes of an elastic wavefield into a seismic interpretation. We interpreted both onshore and marine multicomponent seismic surveys to select the data examples that we use to document the principles of elastic wavefield stratigraphy. We have also used examples from published papers that illustrate some concepts better than did the multicomponent seismic data that were available for our analysis. In each interpretation study, we used rock physics modeling to explain how and why certain geological conditions caused differences in P and S reflectivities that resulted in P-wave seismic sequences and facies being different from depth-equivalent S-wave sequences and facies across the targets we studied.

  19. Induced Seismicity Monitoring System

    Taylor, S. R.; Jarpe, S.; Harben, P.


    There are many seismological aspects associated with monitoring of permanent storage of carbon dioxide (CO2) in geologic formations. Many of these include monitoring underground gas migration through detailed tomographic studies of rock properties, integrity of the cap rock and micro seismicity with time. These types of studies require expensive deployments of surface and borehole sensors in the vicinity of the CO2 injection wells. Another problem that may exist in CO2 sequestration fields is the potential for damaging induced seismicity associated with fluid injection into the geologic reservoir. Seismic hazard monitoring in CO2 sequestration fields requires a seismic network over a spatially larger region possibly having stations in remote settings. Expensive observatory-grade seismic systems are not necessary for seismic hazard deployments or small-scale tomographic studies. Hazard monitoring requires accurate location of induced seismicity to magnitude levels only slightly less than that which can be felt at the surface (e.g. magnitude 1), and the frequencies of interest for tomographic analysis are ~1 Hz and greater. We have developed a seismo/acoustic smart sensor system that can achieve the goals necessary for induced seismicity monitoring in CO2 sequestration fields. The unit is inexpensive, lightweight, easy to deploy, can operate remotely under harsh conditions and features 9 channels of recording (currently 3C 4.5 Hz geophone, MEMS accelerometer and microphone). An on-board processor allows for satellite transmission of parameter data to a processing center. Continuous or event-detected data is kept on two removable flash SD cards of up to 64+ Gbytes each. If available, data can be transmitted via cell phone modem or picked up via site visits. Low-power consumption allows for autonomous operation using only a 10 watt solar panel and a gel-cell battery. The system has been successfully tested for long-term (> 6 months) remote operations over a wide range

  20. San Juan single-well seismic data analysis and modeling study

    Daley, Tom; Wu, C.; Harris, J.M.; Daley, T.M.; Majer, E.L.


    The authors analyze single-well seismic data from the San Juan basin in Northwest New Mexico. The consistently observable events are tube-waves: direct, reflected and multiple tube-waves can be explained by the formation properties and survey geometry except for an anomalous zone with low velocity, high amplitude and horizontal polarization. To aid the data analysis, forward modeling using a variable-grid finite-difference parallel code is performed. The numerical result confirms the identified events in the field observations.

  1. Study of the Stiffening Systems For Seismic Loads in Multistoreyed Building



    Full Text Available Tall building developments have been rapidly increasing worldwide. This paper deals with the evolution of tall building’s structural systems and the technological driving force behind tall building developments. While most representative structural systems for tall buildings are discussed, the emphasis in paper is on the stiffening systems used in the structures for different heights. This paper describes seismic analysis of high-rise building using software STAADPro. with various lateral stiffness system. Some models are prepared using different stiffening systems and analysis is done.

  2. Spatio-Temporal Assessment of Intraplate Seismicity in the Mid-Atlantic US

    Soto-Cordero, L.; Meltzer, A.; Stachnik, J. C.


    Although not as frequent as interplate events, large historic earthquakes in eastern North America have resulted in significant damage from ground shaking and tsunami effects. The Mid-Atlantic US encompasses dense population centers, a heterogeneous built environment, aging infrastructure, and is the site of the only US nuclear power plant where ground motion exceeded the design threshold during an earthquake (Mw 5.8 2011 Virginia). These factors underscore the importance of understanding where earthquakes occur in the US Mid-Atlantic and how they are generated. Globally, intraplate events appear to be spatially and temporally clustered, episodic, and to migrate in space, although diffuse seismicity is observed outside these seismic zones. Previous studies of Mid-Atlantic seismicity propose an apparent clustering into three main seismic zones: Central Virginia (CVSZ), Reading-Lancaster (RLSZ), and Ramapo (RSZ). Explanations for the proposed clustering focus on the presence of potential zones of lithospheric weakness, local stress concentration, or long-lived aftershock sequences. Data from EarthScope USArray and CEUSN provide a new opportunity to assess the extent to which seismicity in the US Mid-Atlantic clusters spatially and the relationship between seismicity and crustal structure. We present a uniform catalog of seismicity from 1568-2016 integrating existing catalogs from the 2014 US NSHM, ISC, ANSS, and USArray ANF. Preliminary cluster analysis shows: (1) seismicity spatially concentrates in a region of transition from thicker to thinner crust and follows the trend of gradients in crustal thickness and the gravity field, and (2) while seismicity in Virginia clusters in a well-defined zone (CVSZ) it appears to be continuous from northern Maryland to New York rather than clustered into discrete seismic zones. We examine earthquake magnitude threshold, repeating earthquakes, and event relocation through the application of waveform cross-correlation techniques

  3. Wavelet analysis for the study of the relations among soil radon anomalies, volcanic and seismic events: the case of Mt. Etna (Italy)

    Ferrera, Elisabetta; Giammanco, Salvatore; Cannata, Andrea; Montalto, Placido


    From November 2009 to April 2011 soil radon activity was continuously monitored using a Barasol® probe located on the upper NE flank of Mt. Etna volcano, close either to the Piano Provenzana fault or to the NE-Rift. Seismic and volcanological data have been analyzed together with radon data. We also analyzed air and soil temperature, barometric pressure, snow and rain fall data. In order to find possible correlations among the above parameters, and hence to reveal possible anomalies in the radon time-series, we used different statistical methods: i) multivariate linear regression; ii) cross-correlation; iii) coherence analysis through wavelet transform. Multivariate regression indicated a modest influence on soil radon from environmental parameters (R2 = 0.31). When using 100-days time windows, the R2 values showed wide variations in time, reaching their maxima (~0.63-0.66) during summer. Cross-correlation analysis over 100-days moving averages showed that, similar to multivariate linear regression analysis, the summer period is characterised by the best correlation between radon data and environmental parameters. Lastly, the wavelet coherence analysis allowed a multi-resolution coherence analysis of the time series acquired. This approach allows to study the relations among different signals either in time or frequency domain. It confirmed the results of the previous methods, but also allowed to recognize correlations between radon and environmental parameters at different observation scales (e.g., radon activity changed during strong precipitations, but also during anomalous variations of soil temperature uncorrelated with seasonal fluctuations). Our work suggests that in order to make an accurate analysis of the relations among distinct signals it is necessary to use different techniques that give complementary analytical information. In particular, the wavelet analysis showed to be very effective in discriminating radon changes due to environmental influences

  4. Time-dependent probabilistic seismic hazard assessment and its application to Hualien City, Taiwan

    C.-H. Chan


    Full Text Available Here, we propose a time-dependent probabilistic seismic hazard assessment and apply it to Hualien City, Taiwan. A declustering catalog from 1940 to 2005 was used to build up a long-term seismicity rate model using a smoothing Kernel function. We also evaluated short-term seismicity rate perturbations according to the rate-and-state friction model, and the Coulomb stress changes imparted by earthquakes from 2006 to 2010. We assessed both long-term and short-term probabilistic seismic hazards by considering ground motion prediction equations for crustal and subduction earthquakes. The long-term seismic hazard in Hualien City gave a PGA (peak ground acceleration of 0.46 g for the 2.1‰ annual exceedance probability. The result is similar to the levels determined in previous studies. Seismic hazards were significantly elevated following the 2007 ML =5.8 earthquake that occurred approximately 10 km from Hualien City. This work presents an assessment of a suitable mechanism for time-dependent probabilistic seismic hazard determinations using an updated earthquake catalog. Using minor model assumptions, our approach provides a suitable basis for rapid re-evaluations and will benefit decision-makers and public officials regarding seismic hazard mitigation.

  5. Missing osteoconductive effect of a resorbable PEO/PBT copolymer in human bone defects: a clinically relevant pilot study with contrary results to previous animal studies.

    Roessler, M; Wilke, A; Griss, P; Kienapfel, H


    PEO/PBT 70/30 (POLYACTIVE(R) 70/30), a degradable porous copolymer with elastic properties, was found to be osteoconductive in many animal studies. The aim of this study was to determine the osteoconductive effect in a human paired control iliac defect model. In seven patients undergoing anterior spinal interbody fusion surgery, two bicortical iliac defects for autograft harvesting were created. The defect size was identical for both defects measuring about 40 x 15 mm (group I). One defect was filled with the degradable implants, whereas the remaining one was left untreated as a control. The defect site for treatment was chosen randomly. In three further patients, only one defect measuring about 40 x 35 mm was created (group II). All patients were examined clinically and radiologically by spiral-CT after 1, 6, 12, 24, and 52 weeks. Three-dimensional reconstructions as well as CT-volumetric measurements using 1 mm sections were used as evaluation methods. In group I, a two-tailed paired t-test showed that the treated defects had significantly less formation of new bone than the untreated ones (p < 0.05 after 12 weeks, p < 0.01 after 52 weeks). Also, in group II, not much bone ingrowth could be observed. The histological evaluation of one patient in group I revealed no bone within the pores, and a fibrous layer between bone and implant was always present. Therefore, PEO/PBT 70/30 cannot be recommended as a bone substitute for clinical use. Differences in bone regeneration between humans and certain animal species as well as inapplicable defect models in previous animal studies are discussed as possible reasons for the failure.

  6. A modeling study on the controlling factors of seismic source distribution and their strength index——Practical analyses of the seismic environmental factors of the Honghe fault


    A model, in which various seismic environmental factors areinvolved, has been developed in the paper on the bases of relevant data. The environmental factors include the crust structure, lithological conditions, fault plan attitude, the crust stress state, pore-fluid pressure and geothermal conditions, etc. The effect of each of the factors on the tectonic movement energy index has been analyzed. The model calculation results indicate that shear fractu-re energy of a fault generally increases with depth; it reached a peak value at a certain depth, then turns gradually attenuated. Of all the factors, the effects of pore-fluid pressure and geothermal conditions on the energy index are of prominence. High pore-fluid pressure and high temperature circumstance may result in decline of the peak value of the shear fracture energy curve, making the depths of the peak value and of the bell-waist value deepened. Such effects restrict strong seismic events, but suitable for micro-seismic activity and/or fault creep. The lower limit of focal depth under such an environment is relatively deep. Contrarily, low pore-fluid pressure and low geothermal temperature circumstance result in increase of the peak value of the shear fracture energy curve, and the curve becoming steep. The later circumstance is favorable to the formation of locked segment where possesses high strength and high-energy accumulation. If these two kind of segments are arranged interactively along a fault zone, such arrangement would boost the energy transition among the segments, forming mechanical circumstance of energy highly accumulated in one segment with adjacent segment(s) less-locked. Such contrast of the strength and energy would provide conditions for strong earthquakes with high stress drop. An analysis of the northwest seg-ment of the Honghe fault has provided some evidence for the modeling results.

  7. Quantifying the influence of previously burned areas on suppression effectiveness and avoided exposure: A case study of the Las Conchas Fire

    Matthew P. Thompson; Patrick Freeborn; Jon D. Rieck; Dave Calkin; Julie W. Gilbertson-Day; Mark A. Cochrane; Michael S. Hand


    We present a case study of the Las Conchas Fire (2011) to explore the role of previously burned areas (wildfires and prescribed fires) on suppression effectiveness and avoided exposure. Methodological innovations include characterisation of the joint dynamics of fire growth and suppression activities, development of a fire line effectiveness framework, and...

  8. Study of some physical aspects previous to design of an exponential experiment; Estudio de algunos aspectos fisicos previos al diseno de una experiencia exponencial

    Caro, R.; Francisco, J. L. de


    This report presents the theoretical study of some physical aspects previous to the design of an exponential facility. The are: Fast and slow flux distribution in the multiplicative medium and in the thermal column, slowing down in the thermal column, geometrical distribution and minimum needed intensity of sources access channels and perturbations produced by possible variations in its position and intensity. (Author) 4 refs.

  9. Probabilistic and Deterministic Seismic Hazard Assessment: A Case Study in Babol

    H.R. Tavakoli


    Full Text Available The risk of earthquake ground motion parameters in seismic design of structures and Vulnerabilityand risk assessment of these structures against earthquake damage are important. The damages caused by theearthquake engineering and seismology of the social and economic consequences are assessed. This paperdetermined seismic hazard analysis in Babol via deterministic and probabilistic methods. Deterministic andprobabilistic methods seem to be practical tools for mutual control of results and to overcome the weaknessof approach alone. In the deterministic approach, the strong-motion parameters are estimated for the maximumcredible earthquake, assumed to occur at the closest possible distance from the site of interest, withoutconsidering the likelihood of its occurrence during a specified exposure period. On the other hand, theprobabilistic approach integrates the effects of all earthquakes expected to occur at different locations duringa specified life period, with the associated uncertainties and randomness taken into account. The calculatedbedrock horizontal and vertical peak ground acceleration (PGA for different years return period of the studyarea are presented.

  10. Feasibility study of the seismic reflection method in Amargosa Desert, Nye County, Nevada

    Brocher, T.M.; Hart, P.E.; Carle, S.F.


    The seismic performance of steel moment-framed buildings has been of particular interest since brittle fractures were discovered at the beam-column connections of some frames following the M6.7 1994 Northridge earthquake. This report presents an investigation of the seismic behavior of an instrumented 13-story steel moment frame building located in the greater Los Angeles area of California. An extensive strong motion dataset, ambient vibration data, engineering drawings and earthquake damage reports are available for this building. The data are described and subsequently analyzed. The results of the analyses show that the building response is more complex than would be expected from its highly symmetrical geometry. The building's response is characterized by low damping in the fundamental mode, larger peak accelerations in the intermediate stories than at the roof, extended periods of vibration after the cessation of strong input shaking, beating in the response, and significant torsion during strong shaking at the top of the concrete piers which extend from the basement to the second floor. The analyses of the data and all damage detection methods employed except one method based on system identification indicate that the response of the structure was elastic in all recorded earthquakes. These findings are in general agreement with the results of intrusive inspections (meaning fireproofing and architectural finishes were removed) conducted on approximately 5 percent of the moment connections following the Northridge earthquake, which found no earthquake damage.

  11. Monitoring methane emission of mud volcanoes by seismic tremor measurements: a pilot study

    D. Albarello


    Full Text Available A new approach for estimating methane emission at mud volcanoes is here proposed based on measurements of the seismic tremor on their surface. Data obtained at the Dashgil mud volcano in Azerbaijan reveal the presence of energy bursts characterized by well-determined features (i.e. waveforms, spectra and polarization properties that can be associated with bubbling at depth. Counting such events provides a possible tool for monitoring gas production in the reservoir, thus minimizing logistic troubles and representing a cheap and effective alternative to more complex approaches. Specifically, we model the energy bursts as the effect of resonant gas bubbles at depth. This modelling allows to estimate the dimension of the bubbles and, consequently, the gas outflow from the main conduit in the assumption that all emissions from depth occur by bubble uprising. The application of this model to seismic events detected at the Dashgil mud volcano during three sessions of measurements carried out in 2006 and 2007 provides gas flux estimates that are in line with those provided by independent measurements at the same structure. This encouraging result suggests that the one here proposed could be considered a new promising, cheap and easy to apply tool for gas flux measurements in bubbling gas seepage areas.

  12. Analyzing the subsurface structure using seismic refraction method: Case study STMKG campus

    Wibowo, Bagus Adi, E-mail: [The State College of Meteorology, Climatology and Geophysics (STMKG), The Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG), Perhubungan 1 Street, South Tangerang, 15221 (Indonesia); Ngadmanto, Drajat [The Center of Research and Development (PUSLITBANG), The Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG), Angkasa I, Jakarta, 10620 (Indonesia); Daryono [The Mitigation of Earthquake and Tsunami, The Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG), Angkasa I, Jakarta, 10620 (Indonesia)


    A geophysic survey is performed to detect subsurface structure under STMKG Campus in Pondok Betung, South Tangerang, Indonesia, using seismic refraction method. The survey used PASI 16S24-U24. The waveform data is acquired from 3 different tracks on the research location with a close range from each track. On each track we expanded 24 geofons with spacing between receiver 2 meters and the total length of each track about 48 meters. The waveform data analysed using 2 different ways. First, used a seismic refractionapplication WINSISIM 12 and second, used a Hagiwara Method. From both analysis, we known the velocity of P-wave in the first and second layer and the thickness of the first layer. From the velocity and the thickness informations we made 2-D vertical subsurface profiles. In this research, we only detect 2 layers in each tracks. The P-wave velocity of first layer is about 200-500 m/s with the thickness of this layer about 3-6 m/s. The P-wave velocity of second layer is about 400-900 m/s. From the P-wave velocity data we interpreted that both layer consisted by similar materials such as top soil, soil, sand, unsaturated gravel, alluvium and clay. But, the P-wave velocity difference between those 2 layers assumed happening because the first layer is soil embankment layer, having younger age than the layer below.

  13. Experimental study on seismic behavior of circular RC columns strengthened with pre-stressed FRP strips

    Zhou, Changdong; Lu, Xilin; Li, Hui; Tian, Teng


    Bonding fiber reinforced polymer (FRP) has been commonly used to improve the seismic behavior of circular reinforced concrete (RC) columns in engineering practice. However, FRP jackets have a significant stress hysteresis effect in this strengthening method, and pre-tensioning the FRP can overcome this problem. This paper presents test results of 25 circular RC columns strengthened with pre-stressed FRP strips under low cyclic loading. The pre-stressing of the FRP strips, types of FRP strips and longitudinal reinforcement, axial load ratio, pre-damage degree and surface treatments of the specimens are considered as the primary factors in the tests. According to the failure modes and hysteresis curves of the specimens, these factors are analyzed to investigate their effect on bearing capacity, ductility, hysteretic behavior, energy dissipation capacity and other important seismic behaviors. The results show that the initial lateral confined stress provided by pre-stressed FRP strips can effectively inhibit the emergence and development of diagonal shear cracks, and change the failure modes of specimens from brittle shear failure to bending or bending-shear failure with better ductility. As a result, the bearing capacity, ductility, energy dissipation capacity and deformation capacity of the strengthened specimens are all significantly improved.

  14. Velocity structure of the Kapuskasing Uplift, northern Ontario, from seismic refraction studies

    Boland, A. V.; Ellis, R. M.


    A crustal scale seismic refraction experiment was conducted over the Kapuskasing structural zone, northern Ontario, in 1984. The zone cuts obliquely across the east-west structural grain of the Superior Province in the Canadian shield and has been proposed as a cross section of Archean crust exposed by thrust faulting along the Ivanhoe Lake cataclastic zone during early Proterozoic time. Five seismic refraction lines of 360-450 km were shot over the area. There were 18 profile shots and two fan shots with a recorder spacing of 2-5 km. We have modeled the travel times and amplitudes of the data from the profile lines and analyzed reflections from the crust-mantle boundary on the fan shots. We have imaged a low-velocity zone under the Abitibi greenstone belt ranging from 4-5 to 9-12 km depth that is underlain by a highly reflective zone. There is a considerable deepening of the Moho from 40-43 km to 50-53 km under and to the west of the southern end of the Kapuskasing structural zone. A high-velocity anomaly of 6.6-6.7 km/s has been imaged in the upper crust down to 20 km depth beneath the Kapuskasing structure with a suggested dip of 15°±2° to the west. This corresponds well to the proposed location of a granulite zone thrust up from the middle or lower crust in the early Proterozoic.

  15. Study of the Seismic Cycle of large Earthquakes in central Peru: Lima Region

    Norabuena, E. O.; Quiroz, W.; Dixon, T. H.


    Since historical times, the Peruvian subduction zone has been source of large and destructive earthquakes. The more damaging one occurred on May 30 1970 offshore Peru’s northern city of Chimbote with a death toll of 70,000 people and several hundred US million dollars in property damage. More recently, three contiguous plate interface segments in southern Peru completed their seismic cycle generating the 1996 Nazca (Mw 7.1), the 2001 Atico-Arequipa (Mw 8.4) and the 2007 Pisco (Mw 7.9) earthquakes. GPS measurements obtained between 1994-2001 by IGP-CIW an University of Miami-RSMAS on the central Andes of Peru and Bolivia were used to estimate their coseismic displacements and late stage of interseismic strain accumulation. However, we focus our interest in central Peru-Lima region, which with its about 9’000,000 inhabitants is located over a locked plate interface that has not broken with magnitude Mw 8 earthquakes since May 1940, September 1966 and October 1974. We use a network of 11 GPS monuments to estimate the interseismic velocity field, infer spatial variations of interplate coupling and its relation with the background seismicity of the region.

  16. Case study - northern Prudhoe Bay development planning using three-dimensional seismic data

    Walsh, T.P.


    Three three-dimensional seismic surveys have been acquired by the Prudhoe Bay unit working interest owners for the purpose of development planning. The most recent of these surveys, the Northern Tier three-dimensional seismic survey, was acquired in 1986 and provides the subject matter for this paper. A new dual-source recording method was extensively field tested prior to its application in production data acquisition. This method of acquisition reduced costs by approximately 25% as compared to conventional (single-source) recording. The 54 mi/sup 2/ subsurface coverage area consists of 118,000 depth points, and cost $4.2 million for acquisition and processing, roughly twice the cost of two development wells in this area. Interactive interpretation of the data volume helps in placing the 80-acre infill wells in the main development area, and helps to identify areas of development potential in the structurally complex northern portion of the field. Traverses are created along the proposed paths of horizontal and high-angle wells to reduce the risk of structural complications during drilling and completion. Predicting target depths to within +- 25 ft and ensuring standoff from faults of 300 - 500 ft are the primary goals of the interpretation. Interaction among the various geoscience and engineering disciplines is common in all phases of this project.

  17. Phase II study of reintroduction of oxaliplatin for advanced colorectal cancer in patients previously treated with oxaliplatin and irinotecan: RE-OPEN study

    Suenaga M


    Full Text Available Mitsukuni Suenaga,1 Nobuyuki Mizunuma,1 Satoshi Matsusaka,1 Eiji Shinozaki,1 Masato Ozaka,1 Mariko Ogura,1 Toshiharu Yamaguchi21Department of Gastroenterology, 2Department of Gastroenterological Surgery, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, JapanBackground: The effectiveness of reintroducing oxaliplatin in patients with metastatic colorectal cancer refractory to standard chemotherapy has not been verified. We performed a single-arm, open-label, Phase II study to evaluate the safety and efficacy of reintroducing oxaliplatin. Methods: Eligible patients had received prior chemotherapy including oxaliplatin and irinotecan that achieved a response or stable disease followed by confirmed disease progression ≥6 months previously during prior oxaliplatin-based therapy. The primary endpoint was the disease control rate (DCR after 12 weeks of treatment starting. The DCR was defined as the sum of patients with complete response, partial response, and stable disease. Results: Thirty-three patients were enrolled. The median age was 62 (range: 35–77 years and the male/female ratio was 19/14. Eastern Cooperative Oncology Group performance status was 0 in 84.8%. Fourteen primary tumors were in the colon and 19 were in the rectum. All patients received modified FOLFOX6 as the protocol treatment. After 12 weeks of treatment starting, the DCR was 39.4% (95% confidence interval 21.8–57.0 and the response rate (complete response and partial response was 6.1%. The median number of chemotherapy cycles was five and the median total dose of oxaliplatin was 425 mg/m2. Median progression-free survival time was 98 days and median overall survival was 300 days. The incidence of grade ≥1 and grade ≥3 allergic reactions was 28.1% and 3.1%, respectively. The incidence of grade ≥1 and grade ≥3 peripheral sensory neuropathy was 53.1% and 0%, respectively. There were no other severe adverse events and no treatment

  18. Key aspects governing induced seismicity

    Buijze, Loes; Wassing, Brecht; Fokker, Peter


    In the past decades numerous examples of earthquakes induced by human-induced changes in subsurface fluid pressures have been reported. This poses a major threat to the future development of some of these operations and calls for an understanding and quantification of the seismicity generated. From geomechanical considerations and insights from laboratory experiments the factors controlling induced seismicity may be grouped into 4 categories; the magnitude of the stress disturbance, the pre-existing stress conditions, the reservoir/fault rock properties and the local geometry. We investigated whether the (relative) contributions of these factors and their influence on magnitudes generated could be recognized by looking at the entire dataset of reported cases of induced seismicity as a whole, and what this might imply for future developments. An extensive database has been built out of over a 160 known cases of induced seismicity worldwide, incorporating the relevant geological, seismological and fluid-related parameters. The cases studied include hydrocarbon depletion and secondary recovery, waste water injection, (enhanced) geothermal systems and hydraulic fracturing with observed magnitudes ranging from less than -1.5 to 7. The parameters taken into account were based on the theoretical background of the mechanisms of induced seismicity and include the injection/depletion-related parameters, (spatial) characteristics of seismicity, lithological properties and the local stress situation. Correlations between the seismic response and the geological/geomechanical characteristics of the various sites were investigated. The injected/depleted volumes and the scale of the activities are major controlling factors on the maximum magnitudes generated. Spatial signatures of seismicity such as the depth and lateral spread of the seismicity were observed to be distinct for different activities, which is useful when considering future operations. Where available the local

  19. Velocity and structural model of the Lower Tagus Basin according to the study of environmental seismic noise

    Gomes Torres, Ricardo Jorge; Furtado, José Augusto; Gonçalves Silva, Hugo; Borges, José Fernando; Caldeira, Bento; Bezzeghoud, Mourad; Carvalho, João


    Along his history the Lower Tagus Valley (LTV) region was shaken by several earthquakes, some of them produced in large ruptures of offshore structures located southwest of the Portuguese coastline. Among these is the Lisbon earthquake of 1 November 1755 (M~8.5-8.7), and other moderates earthquakes that were produced by local sources such as the 1344 (M6.0), 1531 (M7.1) and 1909 (M6.0) earthquakes. Previous simulations [1] have shown high velocity amplification in the region. The model used in the simulations was updated from low to high resolution using all the new available geophysical and geotechnical data on the area (seismic reflection, aeromagnetic, gravimetric, deep wells and geological outcrops) [2]. To confirm this model in the areas where it was derived by potential field methods we use broadband ambient noise measurements collected in about 200 points along seven profiles on the LTV basin, six perpendicular and one parallel to the basin axis. We applied the horizontal to vertical (H/V) spectral ratio method [3] to the seismic noise profiles in order to estimate the distribution of amplification in the basin. The H/V curves obtained reveals the existence of two low frequency peaks centered on 0.2 and 1 Hz [4]. These peaks are strongly related with the thickness of Cenozoic and alluvial sediments. The velocity model obtained by inversion of the H/V curves is in good agreement with borehole data, and results obtained using seismic reflection and gravimetric methods. However, aeromagnetic data overestimates the depth of the base of Cenozoic in the areas where it overlies directly the paleozoic basement, which we attribute either to the existence of Mesozoic units or higher magnetic susceptibilities than expected for the Paleozoic. References: [1] Bezzeghoud, M., Borges, J.F., M., Caldeira (2011). Ground motion simulations of the SW Iberia margin: rupture directivity and earth structure effects. Natural Hazards, pages 1-17. doi:10.1007/s11069-011-9925-2 [2

  20. Non-intrusive Experimental Study on Nuclear Fuel Assembly Response to Seismic Loads

    Weichselbaum, Noah A.

    Experimental measurements of nuclear fuel bundle response to seismic loads have primarily been focused on the response of the structure. Forcing methods have included use of shake tables, however, the majority of work has used hydraulic actuators rigidly connected to a single spacer grid to force the fuel bundle. Structural measurements utilize such instruments as linear variable displacement transducers (LVDT) that are mounted on the structure. From these measurements it has been shown that fuel bundles in prototypical conditions, with an axial flow of 6 m/s, behave markedly different from fuel bundles in still water when there is external forcing on the core from an earthquake. It has also been shown that the structure and fluid are fully coupled. Thus more recently attention has been focused on fluid measurements in the bypass region around fuel bundles with external forcing with laser doppler velocimetry (LDV), which is a point wise fluid velocity measurement technique. This work describes a unique facility that has garnered a large experimental database of fully coupled fluid and structure measurements with time resolved particle image velocimetry (PIV) and digital image correlation (DIC) within a full height 6x6 fuel bundle exposed to seismic forcing on a large 6 degree of freedom shake table. A refractive index matched (RIM) vertical liquid tunnel is mounted on the shake table and houses the fuel bundle which is based on the geometry of a prototypical fuel bundle in a pressurized water reactor (PWR). PIV is obtained with high spatial resolution by rigidly mounting all optical equipment to the test section on the shake table, where the laser light is delivered through high power multi-mode step index fiber optics from a high powered Nd:YLF laser located 10 meters away from the test section. High temporal resolution for the PIV measurements is obtained with state of the art high speed CMOS cameras that record straight to hard drive allowing for increased

  1. Midget Seismic in Sandbox Models

    Krawczyk, C. M.; Buddensiek, M. L.; Philipp, J.; Kukowski, N.; Oncken, O.


    Analog sandbox simulation has been applied to study geological processes to provide qualitative and quantitative insights into specific geological problems. In nature, the structures, which are simulated in those sandbox models, are often inferred from seismic data. With the study introduced here, we want to combine the analog sandbox simulation techniques with seismic physical modeling of those sandbox models. The long-term objectives of this approach are (1) imaging of seismic and seismological events of actively deforming and static 3D analogue models, and (2) assessment of the transferability of the model data to field data in order to improve field data acquisition and interpretation according to the addressed geological problem. To achieve this objective, a new midget-seismic facility for laboratory use was designed and developed, comprising a seismic tank, a PC control unit including piezo-electric transducers, and a positioning system. The first experiments are aimed at studying the wave field properties of the piezo- transducers in order to investigate their feasibility for seismic profiling. The properties investigated are their directionality and the change of waveform due to their size (5-12 mm) compared to the wavelengths (material properties and the effects of wave propagation in an-/isotropic media by physical studies, before we finally start using different seismic imaging and processing techniques on static and actively deforming 3D analog models.


    John Beecherl; Bob A. Hardage


    The objective of this study was to compare the relative merits of shear-wave (S-wave) seismic data acquired with nine-component (9-C) technology and with three-component (3-C) technology. The original proposal was written as if the investigation would be restricted to a single 9-C seismic survey in southwest Kansas (the Ashland survey), on the basis of the assumption that both 9-C and 3-C S-wave images could be created from that one data set. The Ashland survey was designed as a 9-C seismic program. We found that although the acquisition geometry was adequate for 9-C data analysis, the source-receiver geometry did not allow 3-C data to be extracted on an equitable and competitive basis with 9-C data. To do a fair assessment of the relative value of 9-C and 3-C seismic S-wave data, we expanded the study beyond the Ashland survey and included multicomponent seismic data from surveys done in a variety of basins. These additional data were made available through the Bureau of Economic Geology, our research subcontractor. Bureau scientists have added theoretical analyses to this report that provide valuable insights into several key distinctions between 9-C and 3-C seismic data. These theoretical considerations about distinctions between 3-C and 9-C S-wave data are presented first, followed by a discussion of differences between processing 9-C common-midpoint data and 3-C common-conversion-point data. Examples of 9-C and 3-C data are illustrated and discussed in the last part of the report. The key findings of this study are that each S-wave mode (SH-SH, SV-SV, or PSV) involves a different subsurface illumination pattern and a different reflectivity behavior and that each mode senses a different Earth fabric along its propagation path because of the unique orientation of its particle-displacement vector. As a result of the distinct orientation of each mode's particle-displacement vector, one mode may react to a critical geologic condition in a more optimal way than


    John Beecherl; Bob A. Hardage


    The objective of this study was to compare the relative merits of shear-wave (S-wave) seismic data acquired with nine-component (9-C) technology and with three-component (3-C) technology. The original proposal was written as if the investigation would be restricted to a single 9-C seismic survey in southwest Kansas (the Ashland survey), on the basis of the assumption that both 9-C and 3-C S-wave images could be created from that one data set. The Ashland survey was designed as a 9-C seismic program. We found that although the acquisition geometry was adequate for 9-C data analysis, the source-receiver geometry did not allow 3-C data to be extracted on an equitable and competitive basis with 9-C data. To do a fair assessment of the relative value of 9-C and 3-C seismic S-wave data, we expanded the study beyond the Ashland survey and included multicomponent seismic data from surveys done in a variety of basins. These additional data were made available through the Bureau of Economic Geology, our research subcontractor. Bureau scientists have added theoretical analyses to this report that provide valuable insights into several key distinctions between 9-C and 3-C seismic data. These theoretical considerations about distinctions between 3-C and 9-C S-wave data are presented first, followed by a discussion of differences between processing 9-C common-midpoint data and 3-C common-conversion-point data. Examples of 9-C and 3-C data are illustrated and discussed in the last part of the report. The key findings of this study are that each S-wave mode (SH-SH, SV-SV, or PSV) involves a different subsurface illumination pattern and a different reflectivity behavior and that each mode senses a different Earth fabric along its propagation path because of the unique orientation of its particle-displacement vector. As a result of the distinct orientation of each mode's particle-displacement vector, one mode may react to a critical geologic condition in a more optimal way than

  4. Control Effect of a Large Geological Discontinuity on the Seismic Response and Stability of Underground Rock Caverns: A Case Study of the Baihetan #1 Surge Chamber

    Cui, Zhen; Sheng, Qian; Leng, Xianlun


    In this paper, the seismic stability of the #1 surge chamber of the Baihetan hydropower plant, which is influenced by a large dominating geological discontinuity [the interlayer shear weakness zone (ISWZ) C2)], is studied. An advanced, nonlinear, continuously yielding (CY) model was adopted to describe the complex mechanical properties of ISWZ C2. This model considers a power function type, normal stress dependent behavior and the progressive damage that occurred during shear tests. The applicability of the CY model is proved via a comparison with field test results and the theoretical solution. Verification work was conducted in 3DEC code to show that the 3DEC software is suitable for implementing this model. Three ground motion waveforms were utilized to conduct a seismic analysis of the #1 surge chamber after a special response spectrum matching process. The seismic analysis confirmed the control effect of ISWZ C2 on the seismic stability of the cavern. The majority of the cavern's seismic displacement consists of elastic body movement, while the plastic deformation is relatively limited. Further, most of the deformations were caused by the contact deformation of C2. For the contact deformation of C2, the magnitude of permanent shear deformation is larger than that of the normal deformation. The magnitude of permanent shear deformation is more notable along the strike direction of C2, and the permanent normal displacement n of C2 mainly occurs along the dip direction of C2. Finally, the seismic stability of the cavern is assessed via the overload method. The seismic safety factor of the cavern is approximately 2-3.

  5. The study of baseline shift error in strong-motion and ground tilting during co-seismic period with collocated GPS and strong-motion observations

    Tu, Rui; Zhang, Pengfei; Zhang, Rui; Liu, Jinhai; Lu, Xiaochun


    Strong-motion's baseline shift error is very difficult to process precisely; it is mainly caused by the tilting, rotation of the ground and environment noises during the co-seismic period. In the study, we first studied how to effectively extract the strong-motion's baseline shift error with GPS observation; this also provides a new way of correcting the baseline shift errors. Then we studied how to retrieve the ground tilting information of the station point with the collocated GPS and strong-motion observations, the information is an important input parameter of rotational seismology. In addition, both experimental result and seismic data show that the baseline shift error is mainly caused by the ground tiling and rotation during the co-seismic period. Also, there is a strong directly proportional relationship between the baseline shift error and ground tilting, of which the proportionality constant is approximately equal to the value of gravitational acceleration of the station.

  6. Discussion about the relationship between seismic belt and seismic statistical zone

    潘华; 金严; 胡聿贤


    This paper makes a summary of status of delimitation of seismic zones and belts of China firstly in aspects of studying history, purpose, usage, delimiting principles, various presenting forms and main specialties. Then the viewpoints are emphasized, making geographical divisions by seismicity is just the most important purpose of delimiting seismic belts and the concept of seismic belt is also quite different from that of seismic statistical zone used in CPSHA method. The concept of seismic statistical zone and its history of evolvement are introduced too. Large differences between these two concepts exist separately in their statistical property, actual meaning, gradation, required scale, and property of refusing to overlap each other, aim and usage of delimitation. But in current engineering practice, these two concepts are confused. On the one hand, it causes no fit theory for delimiting seismic statistical zone in PSHA to be set up; on the other hand, researches about delimitation of seismic belts with purposes of seismicity zoning and studying on structural environment, mechanism of earthquake generating also pause to go ahead. Major conclusions are given in the end of this paper, that seismic statistical zone bases on the result of seismic belt delimiting, it only arises in and can be used in the especial PSHA method of China with considering spatially and temporally inhomogeneous seismic activities, and its concept should be clearly differentiated from the concept of seismic belt.

  7. Electrical and seismic mixing rules for detecting changes in ground ice content in permafrost studies

    Hauck, Christian; Hilbich, Christin


    Geophysical methods are now widely used in permafrost research to detect and monitor frozen ground and potentially quantify the ground ice content in the soil. Hereby, often a combination of different methods is used to reduce the ambiguities inherent with the indirect nature of geophysical surveys. Geophysical mixing rules and petrophysical relationships originally developed by exploration industry may help to quantitatively relate geophysical variables such as the electrical resistivity or the seismic P-wave velocity to the physical properties of the subsurface. Two of these mixing rules were combined by Hauck et al. (2011) in a so-called 4-phase model to attempt to quantify the ground ice, air- and water content and their changes with time in permafrost environments (e.g. Pellet et al. 2016). However, these mixing rules are often either empirically derived (making use of a large number of borehole samples) or based on a simplified mixing model, i.e. an equal weighting of each phase component (ice, water, soil/rock, air) depending on the actual fractional content of each phase. There is thus no obvious 'best choice' model from the available geophysical approaches. Stimulated by recent theoretical work by Glover (2010), who analysed the relationships between the empirical and theory-derived mixing models, this contribution aims to analyse the applicability of various mixing models for electrical and seismic data sets in the context of detecting and monitoring permafrost degradation. Input data stem from various geophysical surveys around the world and ground truth data for validation is available from corresponding permafrost boreholes from the PERMOS and GTN-P data bases. Glover, P. W. (2010). A generalized Archie's law for n phases. Geophysics, 75(6), E247-E265. Hauck, C., Böttcher, M. and Maurer, H. (2011): A new model for estimating subsurface ice content based on combined electrical and seismic data sets. The Cryosphere, 5, 453-468. Pellet C., Hilbich C

  8. Shoreline response to seismically induced land-level changes - A case study from West Aceh, Indonesia

    Monecke, K.; Meilianda, E.; Walstra, D. J.; Hill, E.; Mc Adoo, B. G.; Qiu, Q.; Storms, J. E. A.; Masputri, A. S.; Mayasari, C. D.; Nasir, M.; Riandi, I.; Setiawan, A.; Templeton, C. K.


    A cross-shore morphodynamic model can be used to simulate shoreline recovery after extreme events, as shown here for the coast of West Aceh, Indonesia, a region largely affected by the December 2004 Sumatra-Andaman earthquake and ensuing Indian Ocean tsunami. Subsidence of 50-100 cm and tsunami scouring during the 2004 event caused the complete destruction of the beach and the landward displacement of the western Acehnese coast by an average of 110 m. Modeled post-seismic land elevation changes as a result of afterslip and viscoelastic mantle relaxation, indicate rapid uplift of 4.4 cm/year in the year following the earthquake, but more moderate uplift rates of 1.4 cm/year since mid-2006. Comparing a series of topographic surveys and satellite images, we reconstruct the build-up of a new beach ridge along a 10 km long stretch of coastline in the years following the event. We then use the cross-shore model UNIBEST-TC developed for a wave-dominated sandy shoreline to determine the controlling factors of shoreline recovery. Input parameters include bathymetric data measured in 2015, grain size characteristics of offshore sediment samples, modeled wave data computed in 7m water depth and tidal elevation data from a nearby tide gauge station. After establishing a cross-shore profile in equilibrium with the prevailing hydrodynamic conditions, we simulate post-seismic land level changes for up to 10 years and compare to the observed coastal development. Our data indicates that the recovery of the Western Acehnese shoreline after the 2004 event was incomplete with the shoreline stabilizing 40-80 meter landward of its pre-2004 tsunami position. Measured variability in shoreline position in the order of a few tens of meters since 2009 can be attributed to seasonal wave climate variability related to the monsoon cycle. The effect of postseismic uplift on shoreline position is small and in the order of only a few meters over 10 years. In the near future, continuing post-seismic

  9. ATLANTIC-DIP: prevalence of metabolic syndrome and insulin resistance in women with previous gestational diabetes mellitus by International Association of Diabetes in Pregnancy Study Groups criteria.

    Noctor, Eoin; Crowe, Catherine; Carmody, Louise A; Kirwan, Breda; O'Dea, Angela; Glynn, Liam G; McGuire, Brian E; O'Shea, Paula M; Dunne, Fidelma P


    Women with previous gestational diabetes (GDM) are a high-risk group for future development of diabetes, metabolic syndrome, and cardiovascular disease. The new International Association of Diabetes in Pregnancy Study Groups (IADPSG) criteria significantly increase the number of women diagnosed with GDM. The long-term metabolic outcome in these women is unknown. We set out to determine the prevalence of metabolic syndrome, using adult treatment panel-III criteria; and insulin resistance, using HOMA2-IR, in white European women with previous GDM. Using a cohort design, we invited women meeting IADPSG GDM criteria across four Irish antenatal centres between 2007 and 2010 to participate. Two hundred and sixty-five women with previous values meeting IADPSG criteria for GDM participated (44 % of the population eligible for participation). Mean age was 36.7 years (SD 5.0). These women were compared with a randomly selected control group of 378 women (mean age 37.6 years, SD 5.1) known to have normal glucose tolerance (NGT) in pregnancy during the same period. A total of 25.3 % of women with previous IADPSG-defined GDM met metabolic syndrome criteria, compared to 6.6 % of women with NGT [at 2.6 (SD 1.0) vs. 3.3 years (SD 0.7) post-partum]. The prevalence of HOMA2-IR >1.8 was higher in women with previous IADPSG-defined GDM (33.6 vs. 9.1 % with NGT, p Women with previous GDM by IADPSG criteria demonstrate a greater than threefold prevalence of metabolic syndrome compared to women with NGT in pregnancy. Efforts to prevent projected long-term consequences of this should focus on interventions both in the preconception and post-partum periods.

  10. A comparative study between China and U.S. on seismic design philosophy and practice of a long span arch bridge

    Xu Yan; George C Lee; Fan Lichu; Hu Shide


    This paper presents the first of a series of case studies on the seismic design of long span bridges (cablestayed bridges, suspension bridges and arch bridges) under a cooperative research project on seismic behavior and design of highway bridges between the State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University and the Multidisciplinary Center for Earthquake Engineering Research, University at Buffalo. The objective of this series of case studies is to examine the differences and similarities on the seismic design practice of long span bridges in China and the U.S., to identify research needs and to develop design guidelines beneficial to bridge engineers in both countries. Unlike short to medium span bridges, long span bridges are not included in most seismic design specifications, mainly because they are location dependent and structurally unique. In this paper, an available model of a steel tied half through arch bridge with a main span of 550m in China is discussed. Analysis is focused on comparisons of the seismic responses due to different ground motions. Seismic design criteria and seismic performance requirements for long span bridges in both countries were first introduced and compared, and then three near field earthquake records with large vertical components were selected as the excitations to examine the seismic behavior and seismic vulnerability of the bridge. Results show that (1) the selected near field ground motions cause larger responses to key components (critical sections) of the bridge (such as arch rib ends) with a maximum increase of more than twice those caused by the site specific ground motions; (2) piers, longitudinal girders and arch crowns are more vulnerable to vertical motions, especially their axial forces; and (3) large vertical components of near field ground motions may not significantly affect the bridge's internal forces provided that their peak acceleration spectra ordinates only appear at periods

  11. Seismic vulnerability and damage of Italian historical centres: A case study in the Campania region

    Formisano, Antonio; Chieffo, Nicola; Fabbrocino, Francesco; Landolfo, Raffaele


    The preservation of masonry buildings typical of Italian historical centres represents a very pressing dilemma founded on recovery need of the urban fabric original character. In the paper, based on a methodology developed by some of the Authors on building aggregates, the seismic vulnerability estimation of some masonry compounds in the heart of the town of San PotitoSannitico (Caserta, Italy) is presented and compared to the results achieved from applying the basic literature method for isolated constructions. Finally, the damage scenario of inspected buildings has been shown by highlighting clearly the influence of different positions of structural units on the damages that masonry aggregates suffer under different grade earthquakes, leading to individuate the most vulnerable buildings.

  12. A seismic refraction study of the crustal structure of the South Kenya Rift

    Henry, W.; Mechie, J.; Maguire, P. K. H.; Patel, J.; Keller, G. R.; Prodehl, C.; Khan, M. A.

    This extended abstract of a forthcoming paper [Henry et al, unpublished manuscript] describes the results from the explosion part of the Kenya Rift International Seismic Project (KRISP 85). This consisted of two lines, each with 50 3-component recording stations [KRISP Working Group,1987; Henry, 1987]. Along the N-S line, the stations were deployed along the rift axis at 3.5 km intervals for about 200 km from Lake Baringo (BAR) to Susua (SUS) (Fig 1), with a few additional stations at the southern end of the line near Magadi (MAG). On the E-W line the stations were deployed at 1 km intervals from Mt. Margaret (MAR), beneath the eastern margin of the rift, westwards for 50 km to Ntulelei (NTU) at the western edge. A few additional stations were deployed further west to Ewaso Nyiro (EWA).

  13. Classifying seismic waveforms from scratch: a case study in the alpine environment

    Hammer, C.; Ohrnberger, M.; Fäh, D.


    Nowadays, an increasing amount of seismic data is collected by daily observatory routines. The basic step for successfully analyzing those data is the correct detection of various event types. However, the visually scanning process is a time-consuming task. Applying standard techniques for detection like the STA/LTA trigger still requires the manual control for classification. Here, we present a useful alternative. The incoming data stream is scanned automatically for events of interest. A stochastic classifier, called hidden Markov model, is learned for each class of interest enabling the recognition of highly variable waveforms. In contrast to other automatic techniques as neural networks or support vector machines the algorithm allows to start the classification from scratch as soon as interesting events are identified. Neither the tedious process of collecting training samples nor a time-consuming configuration of the classifier is required. An approach originally introduced for the volcanic task force action allows to learn classifier properties from a single waveform example and some hours of background recording. Besides a reduction of required workload this also enables to detect very rare events. Especially the latter feature provides a milestone point for the use of seismic devices in alpine warning systems. Furthermore, the system offers the opportunity to flag new signal classes that have not been defined before. We demonstrate the application of the classification system using a data set from the Swiss Seismological Survey achieving very high recognition rates. In detail we document all refinements of the classifier providing a step-by-step guide for the fast set up of a well-working classification system.

  14. Statistical study for the possibility of predication of seismic activity of magnitude ≥5 on Richter scale by use DEMETER microsatellite

    Shaltout, Mosalam; Rateb, A. M.

    Statistical study about the correlation between the magnitudes of seismic activity and the ionospheric perturbations which precedes the occurrences of earthquakes was carried out for more than 180 seismic events distributed all over the world occurred from January 2005 till February 2009 with magnitude equal or greater than 5 on the Richter Scale, the observations made by the French artificial satellite DEMETER which launched on a polar orbit at an altitude of 710 km on June 29th, 2004.The correlation was between the magnitude of the Seismic event /and the changes in the plasma physical parameters of the ionosphere at altitude 710 Km over the Sea level as measured by DEMETER. The perturbations become clearer in case of earthquakes which have high magnitude. These relations still good to discharge of released energy from earthquake preparation zone. The analysis of data show that there is significant very good linear correlation between the magnitude of the seismic activity with the electron density, electron temperature, Ion density .Ion temperature ,Ion of Oxygen density (O+), ion of Helium density (He+) and the Ion of Hydrogen density (H+ ) before the event of occurrence by two or three days . The results are very promising for the possibility of predication of seismic activity by two or three days before its occurrence from DEMETER ionospheric observations or any similar satellites in the future. Keywords:: DEMETER ionospheric perturbations, Electron density, Electron temperature, Ion Density .Ion temperature ,Ion of Oxygen density (O+), Ion of Helium density (He+) and the Ion of Hydrogen density (H+ ).

  15. Advances through collaboration: sharing seismic reflection data via the Antarctic Seismic Data Library System for Cooperative Research (SDLS)

    Wardell, N.; Childs, J. R.; Cooper, A. K.


    The Antarctic Seismic Data Library System for Cooperative Research (SDLS) has served for the past 16 years under the auspices of the Antarctic Treaty (ATCM Recommendation XVI-12) as a role model for collaboration and equitable sharing of Antarctic multichannel seismic reflection (MCS) data for geoscience studies. During this period, collaboration in MCS studies has advanced deciphering the seismic stratigraphy and structure of Antarctica’s continental margin more rapidly than previously. MCS data compilations provided the geologic framework for scientific drilling at several Antarctic locations and for high-resolution seismic and sampling studies to decipher Cenozoic depositional paleoenvironments. The SDLS successes come from cooperation of National Antarctic Programs and individual investigators in “on-time” submissions of their MCS data. Most do, but some do not. The SDLS community has an International Polar Year (IPY) goal of all overdue MCS data being sent to the SDLS by end of IPY. The community science objective is to compile all Antarctic MCS data to derive a unified seismic stratigraphy for the continental margin – a stratigraphy to be used with drilling data to derive Cenozoic circum-Antarctic paleobathymetry maps and local-to-regional scale paleoenvironmental histories.

  16. Prevention and health promotion in undergraduate medical education: Preferences, attitudes and previous knowledge of medical students - a cross-sectional study

    Klement, Andreas; Bretschneider, Kristin; Lautenschläger, Christine; Stang, Andreas; Herrmann, Markus; Haerting, Johannes


    Objective: The interdisciplinary topic "prevention and health promotion" (Q10) was introduced into the medical training in Germany by the new medical licensing regulations in 2004. For the conception of an effective curriculum, it is helpful to know student preferences concerning teaching-formats, attitudes and self-estimated previous knowledge. Little is known concerning student perception of “prevention and health promotion” in Germany. Thus, this explorative cross-sectional study aims to p...

  17. Continous controversy about radiation oncologists' choice of treatment regimens for bone metatases: should we blame doctors, canser-related features, or design of previous clinical studies

    Nieder, Carsten; Pawinski, Adam; Dalhaug, Astrid


    Recent studies from Italy, Japan and Norway have confirmed previous reports, which found that a large variety of palliative radiotherapy regimens are used for painful bone metastases. Routine use of single fraction treatment might or might not be the preferred institutional approach. It is not entirely clear why inter-physician and inter-institution differences continue to persist despite numerous randomized trials, meta-analyses and guidelines, which recommend against more costly and inconve...

  18. Seismic imaging of sandbox experiments – laboratory hardware setup and first reflection seismic sections

    Kukowski, N.; Oncken, O.; M.-L. Buddensiek; C. M. Krawczyk


    With the study and technical development introduced here, we combine analogue sandbox simulation techniques with seismic physical modelling of sandbox models. For that purpose, we designed and developed a new mini-seismic facility for laboratory use, comprising a seismic tank, a PC-driven control unit, a positioning system, and piezo-electric transducers used here the first time in an array mode. To assess the possibilities and limits of seismic imaging of small-scale structures in sandbox mo...

  19. Seismic imaging of sandbox experiments – laboratory hardware setup and first reflection seismic sections

    C. M. Krawczyk; Buddensiek, M.-L.; Oncken, O.; Kukowski, N.


    With the study and technical development introduced here, we combine analogue sandbox simulation techniques with seismic physical modelling of sandbox models. For that purpose, we designed and developed a new mini-seismic facility for laboratory use, comprising a seismic tank, a PC-driven control unit, a positioning system, and piezoelectric transducers used here for the first time in an array mode. To assess the possibilities and limits of seismic imaging of small-scale str...

  20. Transdimensional Bayesian seismic ambient noise tomography across SE Tibet

    Zheng, DingChang; Saygin, Erdinc; Cummins, Phil; Ge, Zengxi; Min, Zhaoxu; Cipta, Athanasius; Yang, Runhai


    We analyze seismic ambient noise data recorded at a set of permanent and temporary stations across southeastern Tibet to image crustal structure. High-resolution phase velocity maps are presented based on Transdimensional Bayesian seismic ambient noise tomography. Seismic images exhibit more apparent horizontal heterogeneities and show more detailed information compared to previous studies based on traditional ambient noise tomography. As noted from the phase velocity image at 25 s, the rigid high velocity anomalies beneath the Sichuan Basin and the South China Fold System act as a blockage to crustal material expansion, and the distribution of velocity anomalies contributes to the interpretation of a surface clockwise rotation pattern. Our results imply a more complex distributed low-velocity zone rather than two isolated channels beneath SE Tibet.

  1. Detailed seismic modeling of induced seismicity at the Groningen gas field

    Paap, B.F.; Steeghs, T.P.H.; Kraaijpoel, D.A.


    We present the results of a detailed seismic modeling study of induced seismicity observed at the Groningen gas field, situated in the North-eastern part of the Netherlands. Seismic simulations are valuable to support the interpretation of observed earthquake waveforms recordings and to increase the

  2. Delineation of seismic source zones based on seismicity parameters and probabilistic evaluation of seismic hazard using logic tree approach

    K S Vipin; T G Sitharam


    The delineation of seismic source zones plays an important role in the evaluation of seismic hazard. In most of the studies the seismic source delineation is done based on geological features. In the present study, an attempt has been made to delineate seismic source zones in the study area (south India) based on the seismicity parameters. Seismicity parameters and the maximum probable earthquake for these source zones were evaluated and were used in the hazard evaluation. The probabilistic evaluation of seismic hazard for south India was carried out using a logic tree approach. Two different types of seismic sources, linear and areal, were considered in the present study to model the seismic sources in the region more precisely. In order to properly account for the attenuation characteristics of the region, three different attenuation relations were used with different weightage factors. Seismic hazard evaluation was done for the probability of exceedance (PE) of 10% and 2% in 50 years. The spatial variation of rock level peak horizontal acceleration (PHA) and spectral acceleration (Sa) values corresponding to return periods of 475 and 2500 years for the entire study area are presented in this work. The peak ground acceleration (PGA) values at ground surface level were estimated based on different NEHRP site classes by considering local site effects.

  3. Seismic modeling of carbonate outcrops

    Stafleu, J.; Schlager, W.; Campbell, E.; Everts, A.J. (Vrije Universiteit, Amsterdam (Netherlands))


    Traditionally, seismic modeling has concentrated on one-dimensional borehole modeling and two-dimensional forward modeling of basic structural-stratigraphic schemes, which are directly compared with real seismic data. Two-dimensional seismic models based on outcrop observations may aid in bridging the gap between the detail of the outcrop and the low resolution of seismic lines. Examples include the Dolomites (north Italy), the High Atlas (Morocco), the Vercors (southeast France) and the Last chance Canyon (New Mexico). The seismic models generally are constructed using the following procedure: (1) construction of a detailed lithological model based on direct outcrop observations; (2) division of the lithological model into lithostratigraphic units, using master bedding planes and important facies transitions as boundaries; (3) assignment of petrophysical properties of these lithostratigraphic units; (4) computation of time sections of reflectivity, using different modeling techniques; and (5) convolution with source wavelets of different frequencies. The lithological detail modeled in the case studies lead to some striking results, particularly the discovery of pseudo-unconformities. Pseudo-unconformities are unconformities in seismics, but correspond to rapid changes of dip and facies in outcrop. None of the outcrop geometries studied were correctly portrayed seismically at 25 Hz frequency. However, in some instances the true relationship would emerge gradually at frequencies of 50 to 100 Hz. These results demonstrate that detailed, outcrop-derived/seismic models can reveal what stratigraphic relationships and features are likely to be resolved under ideal or less ideal conditions, and what pitfalls may befall the interpreter of real seismic data.

  4. The impact of smoking and previous periodontal disease on peri-implant microbiota and health: a retrospective study up to 7-year follow-up.

    Quaranta, Alessandro; Assenza, Bartolomeo; D'Isidoro, Orlando; Profili, Fabia; Polimeni, Antonella; Vozza, Iole


    To evaluate the impact of smoking and previous periodontal disease on peri-implant microbiota and health in medium to long-term maintained patients. A retrospective evaluation of partial edentulous patients restored with dental implants and enrolled in a regular supportive therapy was performed. Inclusion criteria were: medium to long-term periodontal and implant maintenance (at least 5 years), a minimum of 2 implants placed in each patient, absence of systemic diseases that may affect osseointegration. 30 implants in 15 patients were included in the study. Subjects were divided in smokers or non-smokers and between patients previously affected by periodontal disease and periodontally healthy. Peri-implant and periodontal parameters were assessed (PD,BoP, mPI). Microbiological samples were collected around implant and an adjacent tooth. Real- Time Polymerase Chain Reaction (RT-PCR) analysis was performed. In all the three groups no differences in bacterial counts between dental and implant sites were observed. Non smoker, healthy patients: healthy clinical parameters, significant counts of spirochetes in isolated patients. Non smokers with previous periodontal disease: occasional positive BoP values, significant high counts of pathogenic bacteria. Smokers with previous periodontal disease: clinical signs of inflammation including deep pockets and slight bone resorption, significant counts of pathogenic bacteria. Over a follow-up of 5 to 7 years, it is possible to state that the absence of smoking habit and previous periodontal disease positively influences the peri-implant microbiological and clinical conditions in partial edentulous patients restored with dental implants and enrolled in a strict regular supportive therapy.

  5. Role of previous hospitalization in clinically-significant MRSA infection among HIV-infected inpatients: results of a case-control study

    Festa Anna


    Full Text Available Abstract Background HIV-infected subjects have high incidence rates of Staphylococcus aureus infections, with both methicillin-susceptible and methicillin-resistant (MRSA strains. Possible explanations could include the high burden of colonization, the behavioral risk factors, and the frequent exposures to health care facilities of HIV-infected patients. The purpose of the study was to assess the risk factors for clinically- significant methicillin-resistant Staphylococcus aureus (CS-MRSA infections in HIV-infected patients admitted to Infectious Diseases Units. Methods From January 1, 2002 to December 31, 2005, we conducted a retrospective case-control (1:2 study. We identified all the cases of CS-MRSA infections in HIV-infected patients admitted to the National Institute for Infectious Diseases (INMI "Lazzaro Spallanzani" in the 4-year study period. A conditional logistic regression model was used to identify risk factors for CS-MRSA infection. Results We found 27 CS-MRSA infections, i.e. 0.9 CS-MRSA infections per 100 HIV-infected individuals cared for in our Institute. At multivariate analysis, independent predictors of CS-MRSA infection were cumulative hospital stay, invasive procedures in the previous year, and low CD4 cell count. Particularly, the risk for CS-MRSA increased by 14% per an increase of 5 days hospitalization in the previous year. Finally, we identified a low frequency of community-acquired MRSA infections (only 1 of 27; 3.7% among HIV-infected patients. Conclusion Clinicians should be aware of the risk for CS-MRSA infection in the clinical management of HIV-infected patients, especially in those patients with a low CD4 cell count, longer previous hospital stay, and previous invasive procedures.

  6. Role of previous hospitalization in clinically-significant MRSA infection among HIV-infected inpatients: results of a case-control study

    Drapeau, Cecilia MJ; Angeletti, Claudio; Festa, Anna; Petrosillo, Nicola


    Background HIV-infected subjects have high incidence rates of Staphylococcus aureus infections, with both methicillin-susceptible and methicillin-resistant (MRSA) strains. Possible explanations could include the high burden of colonization, the behavioral risk factors, and the frequent exposures to health care facilities of HIV-infected patients. The purpose of the study was to assess the risk factors for clinically- significant methicillin-resistant Staphylococcus aureus (CS-MRSA) infections in HIV-infected patients admitted to Infectious Diseases Units. Methods From January 1, 2002 to December 31, 2005, we conducted a retrospective case-control (1:2) study. We identified all the cases of CS-MRSA infections in HIV-infected patients admitted to the National Institute for Infectious Diseases (INMI) "Lazzaro Spallanzani" in the 4-year study period. A conditional logistic regression model was used to identify risk factors for CS-MRSA infection. Results We found 27 CS-MRSA infections, i.e. 0.9 CS-MRSA infections per 100 HIV-infected individuals cared for in our Institute. At multivariate analysis, independent predictors of CS-MRSA infection were cumulative hospital stay, invasive procedures in the previous year, and low CD4 cell count. Particularly, the risk for CS-MRSA increased by 14% per an increase of 5 days hospitalization in the previous year. Finally, we identified a low frequency of community-acquired MRSA infections (only 1 of 27; 3.7%) among HIV-infected patients. Conclusion Clinicians should be aware of the risk for CS-MRSA infection in the clinical management of HIV-infected patients, especially in those patients with a low CD4 cell count, longer previous hospital stay, and previous invasive procedures. PMID:17470274

  7. Seismic evaluation methods for existing buildings

    Hsieh, B.J.


    Recent US Department of Energy natural phenomena hazards mitigation directives require the earthquake reassessment of existing hazardous facilities and general use structures. This applies also to structures located in accordance with the Uniform Building Code in Seismic Zone 0 where usually no consideration is given to seismic design, but where DOE specifies seismic hazard levels. An economical approach for performing such a seismic evaluation, which relies heavily on the use of preexistent structural analysis results is outlined below. Specifically, three different methods are used to estimate the seismic capacity of a building, which is a unit of a building complex located on a site considered low risk to earthquakes. For structures originally not seismically designed, which may not have or be able to prove sufficient capacity to meet new arbitrarily high seismic design requirement and which are located on low-seismicity sites, it may be very cost effective to perform detailed site-specific seismic hazard studies in order to establish the true seismic threat. This is particularly beneficial, to sites with many buildings and facilities to be seismically evaluated.

  8. Simulating the seismic behaviour of soil slopes and embankments

    Zania, Varvara; Tsompanakis, Yiannis; Psarropoulos, Prodromos


    In the current study the clarification of the main assumptions, related to the two most commonly used methods of seismic slope stability analysis (pseudostatic and permanent deformation) is attempted. The seismic permanent displacements and the corresponding seismic coefficients were determined via...... parametric dynamic numerical analyses taking into account not only the main parameters dominating the seismic slope stability, but also the inherent assumptions of the applied approaches that affect the obtained results. The investigation conclude to a realistic procedure for seismic slope stability...

  9. Simulating the seismic behaviour of soil slopes and embankments

    Zania, Varvara; Tsompanakis, Yiannis; Psarropoulos, Prodromos


    In the current study the clarification of the main assumptions, related to the two most commonly used methods of seismic slope stability analysis (pseudostatic and permanent deformation) is attempted. The seismic permanent displacements and the corresponding seismic coefficients were determined via...... parametric dynamic numerical analyses taking into account not only the main parameters dominating the seismic slope stability, but also the inherent assumptions of the applied approaches that affect the obtained results. The investigation conclude to a realistic procedure for seismic slope stability...

  10. Structural design of active seismic isolation floor with a charging function

    Nakakoji, Hayato; Miura, Nanako


    This study shows an optimum structure of a seismic isolation floor against horizontal ground motions. Although a seismic isolation floor is effective with vibration reduction, the response of the floor becomes larger when excited by long-period ground motions. It is shown that caster equipment move and suffer damage in a seismic isolation structure by an experiment. Moreover, the permissible displacement of the floor is limited. Therefore, the focus is on an active seismic isolation. About active control, the system cannot operate without power supply. To solve these problems an energy regeneration is considered in our previous study. These studies only analyze simple model and did not choose the suitable structure for active control and energy regeneration. This research propose a new structure which has regenerated energy exceeds the energy required for the active control by numerical simulation.

  11. Updated Colombian Seismic Hazard Map

    Eraso, J.; Arcila, M.; Romero, J.; Dimate, C.; Bermúdez, M. L.; Alvarado, C.


    The Colombian seismic hazard map used by the National Building Code (NSR-98) in effect until 2009 was developed in 1996. Since then, the National Seismological Network of Colombia has improved in both coverage and technology providing fifteen years of additional seismic records. These improvements have allowed a better understanding of the regional geology and tectonics which in addition to the seismic activity in Colombia with destructive effects has motivated the interest and the need to develop a new seismic hazard assessment in this country. Taking advantage of new instrumental information sources such as new broad band stations of the National Seismological Network, new historical seismicity data, standardized global databases availability, and in general, of advances in models and techniques, a new Colombian seismic hazard map was developed. A PSHA model was applied. The use of the PSHA model is because it incorporates the effects of all seismic sources that may affect a particular site solving the uncertainties caused by the parameters and assumptions defined in this kind of studies. First, the seismic sources geometry and a complete and homogeneous seismic catalog were defined; the parameters of seismic rate of each one of the seismic sources occurrence were calculated establishing a national seismotectonic model. Several of attenuation-distance relationships were selected depending on the type of seismicity considered. The seismic hazard was estimated using the CRISIS2007 software created by the Engineering Institute of the Universidad Nacional Autónoma de México -UNAM (National Autonomous University of Mexico). A uniformly spaced grid each 0.1° was used to calculate the peak ground acceleration (PGA) and response spectral values at 0.1, 0.2, 0.3, 0.5, 0.75, 1, 1.5, 2, 2.5 and 3.0 seconds with return periods of 75, 225, 475, 975 and 2475 years. For each site, a uniform hazard spectrum and exceedance rate curves were calculated. With the results, it is

  12. Joint Cross Well and Single Well Seismic Studies at Lost Hills, California

    Gritto, Roland; Daley, Thomas M.; Myer, Larry R.


    A series of time-lapse seismic cross well and single well experiments were conducted in a diatomite reservoir to monitor the injection of CO{sub 2} into a hydrofracture zone, based on P- and S-wave data. A high-frequency piezo-electric P-wave source and an orbital-vibrator S-wave source were used to generate waves that were recorded by hydrophones as well as three-component geophones. The injection well was located about 12 m from the source well. During the pre-injection phase water was injected into the hydrofrac-zone. The set of seismic experiments was repeated after a time interval of 7 months during which CO{sub 2} was injected into the hydrofractured zone. The questions to be answered ranged from the detectability of the geologic structure in the diatomic reservoir to the detectability of CO{sub 2} within the hydrofracture. Furthermore it was intended to determine which experiment (cross well or single well) is best suited to resolve these features. During the pre-injection experiment, the P-wave velocities exhibited relatively low values between 1700-1900 m/s, which decreased to 1600-1800 m/s during the post-injection phase (-5%). The analysis of the pre-injection S-wave data revealed slow S-wave velocities between 600-800 m/s, while the post-injection data revealed velocities between 500-700 m/s (-6%). These velocity estimates produced high Poisson ratios between 0.36 and 0.46 for this highly porous ({approx} 50%) material. Differencing post- and pre-injection data revealed an increase in Poisson ratio of up to 5%. Both, velocity and Poisson estimates indicate the dissolution of CO{sub 2} in the liquid phase of the reservoir accompanied by a pore-pressure increase. The single well data supported the findings of the cross well experiments. P- and S-wave velocities as well as Poisson ratios were comparable to the estimates of the cross well data. The cross well experiment did not detect the presence of the hydrofracture but appeared to be sensitive to overall

  13. Observational study of rock mass response to mining induced seismic events and controlled blasting experiments at deep level gold mines in South Africa

    Milev, A.; Durrheim, R. J.; Nakatani, M.; Yabe, Y.; Naoi, M. M.; Ogasawara, H.


    The strong ground motion generated by mining induced seismic events was studied to characterize the rock mass response and to estimate the site effect on the surface of the underground excavations. A stand-alone instruments, especially designed for recording strong ground motions, were installed underground at a number of deep level gold mines in South Africa. The instruments were recording data at the surface of the stope hangingwalls. A maximum value of 3 m/s was measured. Therefore data were compared to the data recorded in the solid rock by the mine seismic networks to determine the site response. The site response was defined as the ratio of the peak ground velocity measured at the surface of the excavations to the peak ground velocity inferred from the mine seismic data measured in the solid rocks. The site response measured at all mines studied was found to be 9 ± 3 times larger on average. In addition a number of simulated rockbursts were conducted underground in order to estimate the rock mass response when subjected to strong ground motion. The rockbursts were simulated by means of large blasts detonated in solid rock close to the sidewall of a tunnel. The numerical models used in the design of the simulated rockbursts were calibrated by small blasts taking place at each experimental site. A dense array of shock type accelerometers was installed along the blasting wall to monitor the attenuation of the strong ground motion as a function of the distance from the source. The attenuation of peak particle velocity was found to be proportional to R-1.7. In order to improve the understanding of the rock mass behaviour around deep level mining the rate of tilt was monitor and then compare to the seismic ground motion. A good correspondence between the rate of tilt and seismic ground motion was found. The rate of coseismic and aseismic tilt, as well as seismicity recorded by the mine seismic network, are approximately constant until the daily blasting time

  14. Time Series Analysis of Soil Radon Data Using Multiple Linear Regression and Artificial Neural Network in Seismic Precursory Studies

    Singh, S.; Jaishi, H. P.; Tiwari, R. P.; Tiwari, R. C.


    This paper reports the analysis of soil radon data recorded in the seismic zone-V, located in the northeastern part of India (latitude 23.73N, longitude 92.73E). Continuous measurements of soil-gas emission along Chite fault in Mizoram (India) were carried out with the replacement of solid-state nuclear track detectors at weekly interval. The present study was done for the period from March 2013 to May 2015 using LR-115 Type II detectors, manufactured by Kodak Pathe, France. In order to reduce the influence of meteorological parameters, statistical analysis tools such as multiple linear regression and artificial neural network have been used. Decrease in radon concentration was recorded prior to some earthquakes that occurred during the observation period. Some false anomalies were also recorded which may be attributed to the ongoing crustal deformation which was not major enough to produce an earthquake.

  15. Seismicity and Tectonics of the West Kaibab Fault Zone, AZ

    Wilgus, J. T.; Brumbaugh, D. S.


    The West Kaibab Fault Zone (WKFZ) is the westernmost bounding structure of the Kaibab Plateau of northern Arizona. The WKFZ is a branching complex of high angle, normal faults downthrown to the west. There are three main faults within the WKFZ, the Big Springs fault with a maximum of 165 m offset, the Muav fault with 350 m of displacement, and the North Road fault having a maximum throw of approximately 90 m. Mapping of geologically recent surface deposits at or crossing the fault contacts indicates that the faults are likely Quaternary with the most recent offsets occurring one of the most seismically active areas in Arizona and lies within the Northern Arizona Seismic Belt (NASB), which stretches across northern Arizona trending NW-SE. The data set for this study includes 156 well documented events with the largest being a M5.75 in 1959 and including a swarm of seven earthquakes in 2012. The seismic data set (1934-2014) reveals that seismic activity clusters in two regions within the study area, the Fredonia cluster located in the NW corner of the study area and the Kaibab cluster located in the south central portion of the study area. The fault plane solutions to date indicate NE-SW to EW extension is occurring in the study area. Source relationships between earthquakes and faults within the WKFZ have not previously been studied in detail. The goal of this study is to use the seismic data set, the available data on faults, and the regional physiography to search for source relationships for the seismicity. Analysis includes source parameters of the earthquake data (location, depth, and fault plane solutions), and comparison of this output to the known faults and areal physiographic framework to indicate any active faults of the WKFZ, or suggested active unmapped faults. This research contributes to a better understanding of the present nature of the WKFZ and the NASB as well.

  16. a Borehole Seismic System for Active and Passive Seimsic Studies to 3 KM at Ptrc's Aquistore Project

    Schmitt, D. R.; Nixon, C.; Kofman, R.; White, D. J.; Worth, K.


    We have constructed a downhole seismic recording system for application to depths of nearly 3 km and temperatures up to 135 °C at Aquistore, an independent research and monitoring project in which liquid CO2 is being stored in a brine and sandstone water formation. The key component to this system is a set of commercially available slim-hole 3-C sondes carrying 15 Hz geophones deployable in open and cased boreholes with diameters as small as 57 mm. The system is currently hosted on a 4-conductor wireline with digital information streamed to the surface recording unit. We have further incorporated these sondes into a mobile passive monitoring unit that includes a number of redundancies such as a multiple Tbyte network accessible RAID hard-drive system (NAS) and a self-designed uninterruptible power supply. The system can be remotely controlled via the internet. The system is currently deployed covering a range of depths from 2850 m to 2910 m. Ambient temperatures at this depth are approximately 110 °C with onboard tool temperatures running at 115 °C. Data is continuously streamed to the NAS for archiving, approximately 11 GBytes of data is recorded per day at the sampling period of 0.5 ms. The lack of noise at this depth allows short data snippets to be flagged with a simple amplitude threshold criteria. The greatly reduced data volume of the snippets allows for ready access via the internet to the system for ongoing quality control. Spurious events, mostly small amplitude tube waves originating at or near the surface, are readily discounted. Active seismic measurements are carried out simultaneously but these require that an appropriately accurate independent GPS based time synchronization be used. Various experiences with event detection, orientation of sondes using both explosives and seismic vibrator, potential overheating of the surface electronics, and issues related to loss of shore power provide for a detailed case study. Aquistore, managed by the

  17. Phase II study of capecitabine as palliative treatment for patients with recurrent and metastatic squamous head and neck cancer after previous platinum-based treatment

    Martinez-Trufero, J; Isla, D; Adansa, J C; Irigoyen, A; Hitt, R; Gil-Arnaiz, I; Lambea, J; Lecumberri, M J; Cruz, J J


    Background: Platinum-based therapy (PBT) is the standard therapy for recurrent and/or metastatic head and neck cancer (HNC), but the incidence of recurrence remains high. This study evaluates the efficacy and tolerability of capecitabine as palliative monotherapy for recurrent HNC previously treated with PBT. Methods: Patients aged 18–75 years, with Eastern Cooperative Oncology Group performance status 0–2, squamous HNC with locoregional and/or metastatic recurrence previously treated with PBT and adequate organ functions, were included. Capecitabine (1.250 mg m−2 BID) was administered on days 1–14 every 21 days for at least two cycles. Results: A total of 40 male patients with a median age of 58 years were analysed. All patients received a median number of four cycles of capecitabine (range: 1–9) and the median relative dose intensity was 91%. Seven patients were not evaluable for response. Overall response rate was 24.2%. Median time to progression and overall survival were 4.8 and 7.3 months, respectively. Haematological adverse events (AEs) grade 3/4 were reported in six patients. Most common grade 3/4 non-haematological AEs were asthenia (12.5%), palmar-plantar eritrodisestesia (10%), mucositis (10%), dysphagia (10%) and diarrhoea (7.5%). Conclusions: Capecitabine seems to be an active, feasible and well-tolerated mode of palliative treatment for advanced HNC patients who have previously received PBT schedules. PMID:20485287

  18. Coal-mining seismicity and ground-shaking hazard: A case study in the Trail Mountain area, Emery County, Utah

    Arabasz, W.J.; Nava, S.J.; McCarter, M.K.; Pankow, K.L.; Pechmann, J.C.; Ake, J.; McGarr, A.


    We describe a multipart study to quantify the potential ground-shaking hazard to Joes Valley Dam, a 58-m-high earthfill dam, posed by mining-induced seismicity (MIS) from future underground coal mining, which could approach as close as ???1 km to the dam. To characterize future MIS close to the dam, we studied MIS located ???3-7 km from the dam at the Trail Mountain coal mine. A 12-station local seismic network (11 stations above ground, one below, combining eight triaxial accelerometers and varied velocity sensors) was operated in the Trail Mountain area from late 2000 through mid-2001 for the dual purpose of (1) continuously monitoring and locating MIS associated with longwall mining at a depth of 0.5-0.6 km and (2) recording high-quality data to develop ground-motion prediction equations for the shallow MIS. (Ground-motion attenuation relationships and moment-tensor results are reported in companion articles.) Utilizing a data set of 1913 earthquakes (M ??? 2.2), we describe space-time-magnitude distributions of the observed MIS and source-mechanism information. The MIS was highly correlated with mining activity both in space and time. Most of the better-located events have depths constrained within ??0.6 km of mine level. For the preponderance (98%) of the 1913 located events, only dilatational P-wave first motions were observed, consistent with other evidence for implosive or collapse-type mechanisms associated with coal mining in this region. We assess a probable maximum magnitude of M 3.9 (84th percentile of a cumulative distribution) for potential MIS close to Joes Valley Dam based on both the worldwide and regional record of coal-mining-related MIS and the local geology and future mining scenarios.

  19. Seismic microzoning from synthetic ground motion parameters Case study, Santiago de Cuba

    Alvarez, L; Pico, R; Vaccari, F


    Synthetic seismograms (P - SV and SH waves) have been calculated along 6 profiles in Santiago de Cuba basin, with a cutoff frequency of 5 Hz, by using the hybrid approach (modal summation for a regional (ID) structure plus finite differences for a local (2D) structure embedded in the first). They correspond to a scenario earthquake of M sub S = 7 that may occur in Oriente fault zone, directly south of the city. As initial data for a seismic microzoning, the characterisation of earthquake effects has been made considering several relative (2D/1D) quantities (PGDR, PGVR, PGAR, DGAR, I sub A R etc.) and functions representative of the ground motion behaviour in soil (2D) with respect to bedrock (ID). The functions are the response spectra ratio RSR(f), already routinely used in this kind of work, and the elastic energy input ratio E sub I R(f), defined, for the first time, in this paper. These data, sampled at 105 sites within all the profiles have been classified in two steps, using logical combinatory algorith...

  20. Application of seismic attributes in structural study and fracture analysis of DQ oil field, Iran

    Shahoo Maleki


    Full Text Available The determination of the most unstable areas in oil fields is critical for addressing engineering problems of wellbore and sand production as well as geologic problems such as understanding dynamic constraints on hydrocarbon migration and fracture permeability. In this research work, coherency seismic attribute has been used for the determination of the most critical areas in terms of drilling stabilities in the DQ oil field, Iran. The results obtained have shown that the (1 predominant features are the SSE–NNW and N–S trends (2 the central part of the DQ structure shows the highest concentration of segment bundles, (3 the segment bundles seem to be aligned along some lineaments oriented SE–NW and SSE–NNW, and (4 on the eastern and western margins of the map there is an anomalous concentration of segments oriented E–W. It can be concluded that coherency attribute is a valuable tool for structural analysis highlighting those areas containing unstable features.

  1. Study of the TEC data obtained from the DORIS stations in relation to seismic activity

    M. Parrot


    Full Text Available Ionospheric data obtained from the DORIS system are used in this paper. The DORIS system is composed of several ground-based beacons which emit at two frequencies (400 MHz and 2 GHz and of receivers on board several satellites (currently SPOT2, SPOT4, SPOT5, Topex-Poseidon, Jason1 and Envisat. Thanks to the density of its network coverage (?50 stations, DORIS provides information on the ionosphere. The TEC (Total Electron Content parameter which is the electron density integrated over the vertical could be obtained from DORIS measurements. In a first step, the paper describes the way to obtain the TEC data from the DORIS ionospheric measurements, and comparisons of the results are done with the IRI2001 model. In a second step, TEC values are used to search for correlation between ionospheric perturbations and seismic activity. Earthquakes of magnitude larger than 5 are chosen close to the ground-based DORIS stations. Among other results, the statistics show that, during the night time and at geomagnetic latitude close to the equator (<10°, TEC amplitude fluctuates at the time of the earthquakes as it is expected, but also 2 days and 5 days before.

  2. A physical model study of effect of fracture aperture on seismic wave


    Based on Hudson’s theoretical hypothesis of equivalent fracture model,inserting aligned round chips in solid model can simulate fractured media. The effect of fractures on the propagation of P and S waves can be observed by changing the fracture thickness. The base model is made of epoxy resin,and the material of fractures is a kind of low-velocity mixture containing silicon rubber. With constant diameter and number of fractures in each model,one group of models can be formed through changing the thickness of fracture. These models have the same fracture density. By using the ultrasonic pulse transmission method,the experiment records time and waveform of P and S waves in the direction parallel and perpendicular to the fracture orientation. The result shows that,with the same fracture density,changing fracture aperture will affect both velocity and amplitude of P and S waves,and the effect on P-wave amplitude is much greater than that on the velocity. Moreover,the variation in velocity of S wave is more obvious in the slow shear wave (S2),while the variation in amplitude is more obvious in the fast shear wave (S1). These properties of wave propagation are useful for seismic data processing and interpretation.

  3. Experimental study on the effect of fracture scale on seismic wave characteristics

    Wei Jianxin; Di Bangrang; Wang Qiang


    In fractured reservoir beds,fracture characteristics affect seismic wave response.Fractured models based on the Hudson's fractured medium theory were constructed in our laboratory by a backfilling technique.For the same fracture density,the variations of the velocity and amplitude of the primary wave and shear wave parallel and perpendicular to the fracture were observed by altering the diameter (scale)of the penny-shaped fracture disk.The model test indicated that an increase of fracture scale increased the velocity and amplitude of the primary wave by about 2%.When the shear wave propagated parallel to the fracture,the velocity of the fast shear wave hardly changed,while the velocity of slow shear wave increased by 2.6% with increasing fracture scale.The results indicated that an increase of fracture scale would reduce the degree of anisotropy of the shear wave.The amplitudes of slow shear waves propagating parallel and perpendicular to fractures decreased with increasing fracture scale.

  4. Seismic calm predictors of rockburst

    Zmushko, Tatjana; Turuntaev, Sergey; Kulikov, Vladimir


    The method of "seismic calm" is widely used for forecasting of strong natural earthquakes (Sobolev G.A., Ponomarev A.V., 2003). The "seismic calm" means that during some time period before the main earthquake, the smaller events (with energies of several order smaller than that of the main earthquake) don't occur. In the presented paper the applicability of the method based on the idea of seismic calm for forecasting rockburst is considered. Three deposits (with seismicity induced by mining) are analyzed: Tashtagol iron deposit (Altai, Russia), Vorkuta (North Ural, Russia) and Barentsburg (Spitsbergen, Norway) coalmines. Local seismic monitoring networks are installed on each of them. The catalogues of seismic events were processed and strong events (rockbursts) were studied (Vorkuta M=2,3; Barentsburg M=1,8; Tashtagol M=1,9÷2,2). All catalogues cover at least two years (Vorkuta - 2008-2011, Barentsburg - 2011-2012, Tashtagol - 2002-2012). It was found that the number of seismic events with magnitudes M=0,5÷1 decreased in a month before the main strong event at Vorkuta coalmines. This event was not directly related with coal mining, its epicenter was located aside of the area of coal mining. In Barentsburg mine the rockburst wasn't so strong as in Vorkuta. The number of events with energies M=0,5 decreased slightly before the rockburst, but not so obviously as in Vorkuta case. The seismic events with high energies occur often at Tashtagol iron deposit. Mining methods used there differ from the coal deposit mining. At coalmines the mining combine runs from edge to edge of the wall, cutting off the coal. The considered iron deposit is developed by a method of block blasting. Not all rockbursts occur immediately after the blasting, so, the problem of the rockburst prediction is important for mining safety. To find rockburst precursors it is necessary to separate the events occurred due to the block blasting from the seismic events due to relocation of stresses in

  5. Risk for High Depressive Symptoms in Diagnosed and Previously Undetected Diabetes: 5-Year Follow-Up Results of the Heinz Nixdorf Recall Study

    Icks, Andrea; Albers, Bernd; Haastert, Burkhard; Pechlivanis, Sonali; Pundt, Noreen; Slomiany, Uta; Erbel, Raimund; Jöckel, Karl-Heinz; Kruse, Johannes; Kulzer, Bernd; Nowotny, Bettina; Herder, Christian; Giani, Guido; Moebus, Susanne


    Objective The objective of this study was to determine the risk for the development of high depressive symptoms in study participants with diagnosed and previously undetected diabetes mellitus compared to those without diabetes in a prospective population-based cohort study in Germany. Methods We estimated the 5-year cumulative incidence of high depressive symptoms in participants without high depressive symptoms at baseline (n = 3,633, 51.4% men, mean age (SD) 59.1 (7.6) years, 7.0% diagnosed diabetes, 5.3% previously undetected diabetes) from the population-based Heinz Nixdorf Recall study. Diabetes was assessed by self-report, medication, and blood glucose. High depressive symptoms were assessed using CES-D. We calculated odds ratios and their corresponding 95% confidence interval, using multiple logistic regression analyses. Result Cumulative 5-year incidences (95% CI) of high depressive symptoms in participants with diagnosed, undetected, and without diabetes were 7.1 (4.2–10.9), 4.1 (1.8–8.0), and 6.5 (5.6–7.4), respectively. The age-sex-adjusted OR for developing high depressive symptoms was 1.22 (0.74–2.03) in participants with diagnosed compared to those without diabetes, and 1.00 (0.59–1.68) after adjustment for BMI, physical activity, education, stroke, and myocardial infarction. The age-sex adjusted OR for developing high depressive symptoms in participants with previously undetected diabetes compared to those without diabetes was 0.72; 0.35–1.48; and fully adjusted 0.62; 0.30–1.30. Conclusion We found no significant associations, maybe due to low power. However, our results are in line with a recent meta-analysis suggesting that risk of developing high depressive symptoms in patients with diagnosed diabetes may be moderately higher than in those without diabetes, and that comorbidity may explain in part this association. In participants with previously undetected diabetes, this first longitudinal study indicates that the risk is not

  6. Risk for high depressive symptoms in diagnosed and previously undetected diabetes: 5-year follow-up results of the Heinz Nixdorf Recall study.

    Andrea Icks

    Full Text Available OBJECTIVE: The objective of this study was to determine the risk for the development of high depressive symptoms in study participants with diagnosed and previously undetected diabetes mellitus compared to those without diabetes in a prospective population-based cohort study in Germany. METHODS: We estimated the 5-year cumulative incidence of high depressive symptoms in participants without high depressive symptoms at baseline (n = 3,633, 51.4% men, mean age (SD 59.1 (7.6 years, 7.0% diagnosed diabetes, 5.3% previously undetected diabetes from the population-based Heinz Nixdorf Recall study. Diabetes was assessed by self-report, medication, and blood glucose. High depressive symptoms were assessed using CES-D. We calculated odds ratios and their corresponding 95% confidence interval, using multiple logistic regression analyses. RESULT: Cumulative 5-year incidences (95% CI of high depressive symptoms in participants with diagnosed, undetected, and without diabetes were 7.1 (4.2-10.9, 4.1 (1.8-8.0, and 6.5 (5.6-7.4, respectively. The age-sex-adjusted OR for developing high depressive symptoms was 1.22 (0.74-2.03 in participants with diagnosed compared to those without diabetes, and 1.00 (0.59-1.68 after adjustment for BMI, physical activity, education, stroke, and myocardial infarction. The age-sex adjusted OR for developing high depressive symptoms in participants with previously undetected diabetes compared to those without diabetes was 0.72; 0.35-1.48; and fully adjusted 0.62; 0.30-1.30. CONCLUSION: We found no significant associations, maybe due to low power. However, our results are in line with a recent meta-analysis suggesting that risk of developing high depressive symptoms in patients with diagnosed diabetes may be moderately higher than in those without diabetes, and that comorbidity may explain in part this association. In participants with previously undetected diabetes, this first longitudinal study indicates that the risk is not


    Hata, Yoshiya; Ichii, Koji; Yamada, Masayuki; Tokida, Ken-Ichi; Takezawa, Koichiro; Shibao, Susumu; Mitsushita, Junji; Murata, Akira; Furukawa, Aiko; Koizumi, Keigo

    Accurate evaluation on the seismic response characteristics of a road embankment is very important for the rational seismic assessment. However, in a lot of previous studies, the seismic response characteristics of an embankment were evaluated based on the results of shaking table test, centrifuge model test and dynamic FEM analysis. In this study, the transfer function and the shear wave velocity of a road embankment were evaluated based on the in-situ records of moderate earthquake observation and microtremor measurement. Test results show the possibility that the shear wave velocity of an embankment can be estimated by the earthquake observation or the microtremor measurement and the dynamic linear FEM analysis.

  8. Urban Vulnerability Assessment to Seismic Hazard through Spatial Multi-Criteria Analysis. Case Study: the Bucharest Municipality/Romania

    Armas, Iuliana; Dumitrascu, Silvia; Bostenaru, Maria


    In the context of an explosive increase in value of the damage caused by natural disasters, an alarming challenge in the third millennium is the rapid growth of urban population in vulnerable areas. Cities are, by definition, very fragile socio-ecological systems with a high level of vulnerability when it comes to environmental changes and that are responsible for important transformations of the space, determining dysfunctions shown in the state of the natural variables (Parker and Mitchell, 1995, The OFDA/CRED International Disaster Database). A contributing factor is the demographic dynamic that affects urban areas. The aim of this study is to estimate the overall vulnerability of the urban area of Bucharest in the context of the seismic hazard, by using environmental, socio-economic, and physical measurable variables in the framework of a spatial multi-criteria analysis. For this approach the capital city of Romania was chosen based on its high vulnerability due to the explosive urban development and the advanced state of degradation of the buildings (most of the building stock being built between 1940 and 1977). Combining these attributes with the seismic hazard induced by the Vrancea source, Bucharest was ranked as the 10th capital city worldwide in the terms of seismic risk. Over 40 years of experience in the natural risk field shows that the only directly accessible way to reduce the natural risk is by reducing the vulnerability of the space (Adger et al., 2001, Turner et al., 2003; UN/ISDR, 2004, Dayton-Johnson, 2004, Kasperson et al., 2005; Birkmann, 2006 etc.). In effect, reducing the vulnerability of urban spaces would imply lower costs produced by natural disasters. By applying the SMCA method, the result reveals a circular pattern, signaling as hot spots the Bucharest historic centre (located on a river terrace and with aged building stock) and peripheral areas (isolated from the emergency centers and defined by precarious social and economic

  9. Identification of a gene set to evaluate the potential effects of loud sounds from seismic surveys on the ears of fishes: a study with Salmo salar.

    Andrews, C D; Payne, J F; Rise, M L


    identified the transcript encoding growth hormone I as up-regulated by loud sound, supporting previous evidence linking growth hormone to hair cell regeneration in fishes. Quantitative (q) reverse transcription (RT) polymerase chain reaction (qRT-PCR) analyses confirmed dysregulation of some microarray-identified transcripts and in some cases revealed a high level of biological variability in the exposed group. These results support the potential utility of molecular biomarkers to evaluate the effect of seismic surveys on fishes with studies on the ears being placed in a priority category for development of exposure-response relationships. Knowledge of such relationships is necessary for addressing the question of potential size of injury zones.

  10. Shallow landslide susceptibility model for the Oria river basin, Gipuzkoa province (North of Spain). Application of the logistic regression and comparison with previous studies.

    Bornaetxea, Txomin; Antigüedad, Iñaki; Ormaetxea, Orbange


    In the Oria river basin (885 km2) shallow landslides are very frequent and they produce several roadblocks and damage in the infrastructure and properties, causing big economic loss every year. Considering that the zonification of the territory in different landslide susceptibility levels provides a useful tool for the territorial planning and natural risk management, this study has the objective of identifying the most prone landslide places applying an objective and reproducible methodology. To do so, a quantitative multivariate methodology, the logistic regression, has been used. Fieldwork landslide points and randomly selected stable points have been used along with Lithology, Land Use, Distance to the transport infrastructure, Altitude, Senoidal Slope and Normalized Difference Vegetation Index (NDVI) independent variables to carry out a landslide susceptibility map. The model has been validated by the prediction and success rate curves and their corresponding area under the curve (AUC). In addition, the result has been compared to those from two landslide susceptibility models, covering the study area previously applied in different scales, such as ELSUS1000 version 1 (2013) and Landslide Susceptibility Map of Gipuzkoa (2007). Validation results show an excellent prediction capacity of the proposed model (AUC 0,962), and comparisons highlight big differences with previous studies.

  11. Food intake during the previous 24 h as a percentage of usual intake: a marker of hypoxia in infants with bronchiolitis: an observational, prospective, multicenter study

    Corrard François


    Full Text Available Abstract Background Hypoxia associated with bronchiolitis is not always easy to assess on clinical grounds alone. The aim of this study was to determine the value of food intake during the previous 24 hours (bottle and spoon feeding, as a percentage of usual intake (24h FI, as a marker of hypoxia, and to compare its diagnostic value with that of usual clinical signs. Methods In this observational, prospective, multicenter study, 18 community pediatricians, enrolled 171 infants, aged from 0 to 6 months, with bronchiolitis (rhinorrhea + dyspnea + cough + expiratory sounds. Infants with risk factors (history of prematurity, chronic heart or lung disorders, breast-fed infants, and infants having previously been treated for bronchial disorders were excluded. The 24h FI, subcostal, intercostal, supracostal retractions, nasal flaring, respiratory rate, pauses, cyanosis, rectal temperature and respiratory syncytial virus test results were noted. The highest stable value of transcutaneous oxygen saturation (SpO2 was recorded. Hypoxia was noted if SpO2 was below 95% and verified. Results 24h FI ≥ 50% was associated with a 96% likelihood of SpO2 ≥ 95% [95% CI, 91–99]. In univariate analysis, 24h FI  Conclusion In practice, the measure of 24 h FI may be useful in identifying hypoxia and deserves further study.

  12. Assessment of Quantitative Aftershock Productivity Potential in Mining-Induced Seismicity

    Kozłowska, Maria; Orlecka-Sikora, Beata


    Strong mining-induced earthquakes exhibit various aftershock patterns. The aftershock productivity is governed by the geomechanical properties of rock in the seismogenic zone, mining-induced stress and coseismic stress changes related to the main shock's magnitude, source geometry and focal mechanism. In order to assess the quantitative aftershock productivity potential in the mining environment we apply a forecast model based on natural seismicity properties, namely constant tectonic loading and the Gutenberg-Richter frequency-magnitude distribution. Although previous studies proved that mining-induced seismicity does not obey the simple power law, here we apply it as an approximation of seismicity distribution to resolve the number of aftershocks, not considering their magnitudes. The model used forecasts the aftershock productivity based on the background seismicity level estimated from an average seismic moment released per earthquake and static stress changes caused by a main shock. Thus it accounts only for aftershocks directly triggered by coseismic process. In this study we use data from three different mines, Mponeng (South Africa), Rudna and Bobrek (Poland), representing different geology, exploitation methods and aftershock patterns. Each studied case is treated with individual parameterization adjusted to the data specifics. We propose the modification of the original model, i.e. including the non-uniformity of M 0, resulting from spatial correlation of mining-induced seismicity with exploitation. The results show that, even when simplified seismicity distribution parameters are applied, the modified model predicts the number of aftershocks for each analyzed case well and accounts for variations between these values. Such results are thus another example showing that coseismic processes of mining-induced seismicity reflect features of natural seismicity and that similar models can be applied to study the aftershock rate in both the natural and the

  13. Assessment of Quantitative Aftershock Productivity Potential in Mining-Induced Seismicity

    Kozłowska, Maria; Orlecka-Sikora, Beata


    Strong mining-induced earthquakes exhibit various aftershock patterns. The aftershock productivity is governed by the geomechanical properties of rock in the seismogenic zone, mining-induced stress and coseismic stress changes related to the main shock's magnitude, source geometry and focal mechanism. In order to assess the quantitative aftershock productivity potential in the mining environment we apply a forecast model based on natural seismicity properties, namely constant tectonic loading and the Gutenberg-Richter frequency-magnitude distribution. Although previous studies proved that mining-induced seismicity does not obey the simple power law, here we apply it as an approximation of seismicity distribution to resolve the number of aftershocks, not considering their magnitudes. The model used forecasts the aftershock productivity based on the background seismicity level estimated from an average seismic moment released per earthquake and static stress changes caused by a main shock. Thus it accounts only for aftershocks directly triggered by coseismic process. In this study we use data from three different mines, Mponeng (South Africa), Rudna and Bobrek (Poland), representing different geology, exploitation methods and aftershock patterns. Each studied case is treated with individual parameterization adjusted to the data specifics. We propose the modification of the original model, i.e. including the non-uniformity of M 0, resulting from spatial correlation of mining-induced seismicity with exploitation. The results show that, even when simplified seismicity distribution parameters are applied, the modified model predicts the number of aftershocks for each analyzed case well and accounts for variations between these values. Such results are thus another example showing that coseismic processes of mining-induced seismicity reflect features of natural seismicity and that similar models can be applied to study the aftershock rate in both the natural and the

  14. A detailed seismic anisotropy study during the 2011-2012 unrest period in the Santorini Volcanic Complex

    Kaviris, G.; Papadimitriou, P.; Kravvariti, Ph.; Kapetanidis, V.; Karakonstantis, A.; Voulgaris, N.; Makropoulos, K.


    The Santorini Volcanic Complex (SVC) is an area in the Southern Aegean (Greece) which has been characterized by low seismicity rates for the last decades, especially in the Santorini Caldera where they have been very low until 2010. This pattern changed completely in February 2011, when intense microseismic activity was initiated within the Caldera. During the manual analysis of the events, the shear-wave splitting phenomenon was observed, revealing the existence of an anisotropic upper crust in the SVC area. A detailed anisotropy study has been conducted using 231 events within the shear-wave window that fulfilled the selection criteria. The polarization direction of the fast shear-wave, the time-delay between the two split shear-waves and the source polarization direction were calculated after visual inspection, using both the polarigram and the hodogram representations. This procedure, applied for eight local stations, resulted in the determination of 340 splitting parameters. The obtained mean anisotropy directions are not homogeneous, revealing a complex regime in the activated area. Nevertheless, these results are explained by the APE model, related to the stress-sensitive behavior of fluid-saturated microcracked rocks. A detailed analysis of the temporal evolution of both the time-delay and anisotropy direction was carried out. The time-delays measured in the “band-1” window exhibit gradual increase and sudden drop that can be related to imminent bursts of seismicity, as well as to the major Mw = 5.1 and 5.2 events which took place about 40 km SW of Santorini on 26 and 27 January 2012, respectively. On the other hand, no significant temporal variations or 90° flips of the Sfast polarization direction were observed.

  15. Advanced Seismic While Drilling System

    Robert Radtke; John Fontenot; David Glowka; Robert Stokes; Jeffery Sutherland; Ron Evans; Jim Musser


    A breakthrough has been discovered for controlling seismic sources to generate selectable low frequencies. Conventional seismic sources, including sparkers, rotary mechanical, hydraulic, air guns, and explosives, by their very nature produce high-frequencies. This is counter to the need for long signal transmission through rock. The patent pending SeismicPULSER{trademark} methodology has been developed for controlling otherwise high-frequency seismic sources to generate selectable low-frequency peak spectra applicable to many seismic applications. Specifically, we have demonstrated the application of a low-frequency sparker source which can be incorporated into a drill bit for Drill Bit Seismic While Drilling (SWD). To create the methodology of a controllable low-frequency sparker seismic source, it was necessary to learn how to maximize sparker efficiencies to couple to, and transmit through, rock with the study of sparker designs and mechanisms for (a) coupling the sparker-generated gas bubble expansion and contraction to the rock, (b) the effects of fluid properties and dynamics, (c) linear and non-linear acoustics, and (d) imparted force directionality. After extensive seismic modeling, the design of high-efficiency sparkers, laboratory high frequency sparker testing, and field tests were performed at the University of Texas Devine seismic test site. The conclusion of the field test was that extremely high power levels would be required to have the range required for deep, 15,000+ ft, high-temperature, high-pressure (HTHP) wells. Thereafter, more modeling and laboratory testing led to the discovery of a method to control a sparker that could generate low frequencies required for deep wells. The low frequency sparker was successfully tested at the Department of Energy Rocky Mountain Oilfield Test Center (DOE RMOTC) field test site in Casper, Wyoming. An 8-in diameter by 26-ft long SeismicPULSER{trademark} drill string tool was designed and manufactured by TII

  16. Infrasound Generation from the HH Seismic Hammer.

    Jones, Kyle Richard


    The HH Seismic hammer is a large, "weight-drop" source for active source seismic experiments. This system provides a repetitive source that can be stacked for subsurface imaging and exploration studies. Although the seismic hammer was designed for seismological studies it was surmised that it might produce energy in the infrasonic frequency range due to the ground motion generated by the 13 metric ton drop mass. This study demonstrates that the seismic hammer generates a consistent acoustic source that could be used for in-situ sensor characterization, array evaluation and surface-air coupling studies for source characterization.

  17. Infrasound Generation from the HH Seismic Hammer.

    Jones, Kyle Richard


    The HH Seismic hammer is a large, "weight-drop" source for active source seismic experiments. This system provides a repetitive source that can be stacked for subsurface imaging and exploration studies. Although the seismic hammer was designed for seismological studies it was surmised that it might produce energy in the infrasonic frequency range due to the ground motion generated by the 13 metric ton drop mass. This study demonstrates that the seismic hammer generates a consistent acoustic source that could be used for in-situ sensor characterization, array evaluation and surface-air coupling studies for source characterization.

  18. Quantitative Seismic Amplitude Analysis

    Dey, A. K.


    The Seismic Value Chain quantifies the cyclic interaction between seismic acquisition, imaging and reservoir characterization. Modern seismic innovation to address the global imbalance in hydrocarbon supply and demand requires such cyclic interaction of both feed-forward and feed-back processes. Currently, the seismic value chain paradigm is in a feed-forward mode. Modern seismic data now have the potential to yield the best images in terms of spatial resolution, amplitude accuracy, and incre...

  19. Static behaviour of induced seismicity

    Mignan, Arnaud


    The standard paradigm to describe seismicity induced by fluid injection is to apply nonlinear diffusion dynamics in a poroelastic medium. I show that the spatiotemporal behaviour and rate evolution of induced seismicity can, instead, be expressed by geometric operations on a static stress field produced by volume change at depth. I obtain laws similar in form to the ones derived from poroelasticity while requiring a lower description length. Although fluid flow is known to occur in the ground, it is not pertinent to the behaviour of induced seismicity. The proposed model is equivalent to the static stress model for tectonic foreshocks generated by the Non- Critical Precursory Accelerating Seismicity Theory. This study hence verifies the explanatory power of this theory outside of its original scope.

  20. Effect of Kepler calibration on global seismic and background parameters

    Salabert, D; Mathur, S; Ballot, J


    Calibration issues associated to scrambled collateral smear affecting the Kepler short-cadence data were discovered in the Data Release 24 and were found to be present in all the previous data releases since launch. In consequence, a new Data Release 25 was reprocessed to correct for these problems. We perform here a preliminary study to evaluate the impact on the extracted global seismic and background parameters between data releases. We analyze the sample of seismic solar analogs observed by Kepler in short cadence between Q5 and Q17. We start with this set of stars as it constitutes the best sample to put the Sun into context along its evolution, and any significant differences on the seismic and background parameters need to be investigated before any further studies of this sample can take place. We use the A2Z pipeline to derive both global seismic parameters and background parameters from the Data Release 25 and previous data releases and report on the measured differences.

  1. Geophysical Studies of Seismic Hazard in the Tahoe City Sub-basin, Lake Tahoe, California

    Muehlberg, J. M.; Schweickert, R. A.; McHugh, J.; Rasmussen, T.; Louie, J. N.


    The Lake Tahoe basin has the potential for serious earthquakes and earthquake-related tsunamis. The history of lake level fluctuations should be recorded in sediments beneath the Lake's outlet at Tahoe City. Borehole data show the sediments consist primarily of a thick sequence of lacustrine silts and clays with interbedded sands. Beneath this unit is an older Q-T (?) sand and gravel sequence of unknown origin. The lacustrine deposits locally rest upon 2.0 Ma latites, which in turn rest upon the older sand and gravel sequence. Near the outlet, several fault scarps displace units less than 2.0 m.y. old. These scarps may influence the stability of the dam across the outlet and the sequence and extent of lake level high stands. Our project is integrating geophysical and stratigraphic data to further define and describe the Tahoe City sub-basin. We collected new gravity data to provide an estimate of basin depths across the outlet and help define subsurface faults. Preliminary data suggest the maximum basin depth is 180 m, near the outlet. Refraction microtremor surveys yielded information about stratigraphy and shear velocities of the Quaternary deposits. The average shear wave velocity to 30-m depth obtained for this area is 334 m/s. These values correspond to a NEHRP soil hazard class of D, similar to that found in other lacustrine basins of the region. Soils in this NEHRP class tend to show a significant amplification of shaking, posing increased hazard to structures. We are combining stratigraphic with gravity and seismic data to produce geologic cross sections having information on basin depths and Quaternary faults.

  2. Study on the relationship between geothermal exploitation and seismic activity in Xi'an region

    吴富春; 宋立胜; 朱兴国; 王锋; 景北科; 董星宏; 方炜; 左永青


    Based on the analysis of the induced earthquakes in China and abroad, we get some ideas about earthquakes induced by pumping water out of a well or injecting water into a well. The induced earthquakes usually occur near the well, and they are generally small earthquakes. The earthquake sources are shallow, and they belong to the main shock-after shock type of earthquake or the swarm-type of earthquake. The magnitude and the quantity of the induced earthquakes obviously depend on the pressure and the quantity of water pumped or injected. These earthquakes happen as soon as pumping or injecting occurrence, or after ten or twenty days, they may occur at the time of injecting mud or injecting high pressure water when a well is being drilled, or at the time when the ground water is being normally exploited. A large quantity of hot water has been exploited since 1990 in Xi'an, and the quantity of water exploited has been increasing year by year, as a result the groundwater level has been dropping with the water pumped out and the water level is high in summer and low in winter. The earthquakes in Xi'an region belong to the solitary-type and they spread outside Xi'an city where the wells are concentrated but no earthquake happens.The seismic frequency and the energy released have no relation with the quantity of water exploitation or the water level in the well. It is considered that geothermal exploitation does not induce earthquakes in and around Xi'an because of its specially geological condition.

  3. Reevaluation of the Seismicity and seismic hazards of Northeastern Libya

    Ben Suleman, abdunnur; Aousetta, Fawzi


    Libya, located at the northern margin of the African continent, underwent many episodes of orogenic activities. These episodes of orogenic activities affected and shaped the geological setting of the country. This study represents a detailed investigation that aims to focus on the seismicity and its implications on earthquake hazards of Northeastern Libya. At the end of year 2005 the Libyan National Seismological Network starts functioning with 15 stations. The Seismicity of the area under investigation was reevaluated using data recorded by the recently established network. The Al-Maraj earthquake occurred in May 22nd 2005was analyzed. This earthquake was located in a known seismically active area. This area was the sight of the well known 1963 earthquake that kills over 200 people. Earthquakes were plotted and resulting maps were interpreted and discussed. The level of seismic activity is higher in some areas, such as the city of Al-Maraj. The offshore areas north of Al-Maraj seem to have higher seismic activity. It is highly recommended that the recent earthquake activity is considered in the seismic hazard assessments for the northeastern part of Libya.

  4. Validating induced seismicity forecast models - Induced Seismicity Test Bench

    Kiraly-Proag, Eszter; Gischig, Valentin; Wiemer, Stefan; Karvounis, Dimitrios; Doetsch, Joseph


    Induced earthquakes often accompany fluid injection, and the seismic hazard they pose threatens various underground engineering projects. Models to monitor and control induced seismic hazard with traffic light systems should be probabilistic, forward-looking, and updated as new data arrive. In this study, we propose an Induced Seismicity Test Bench to test and rank such models; this test bench can be used for model development, model selection, and ensemble model building. We apply the test bench to data from the Basel 2006 and Soultz-sous-For\\^ets 2004 geothermal stimulation projects, and we assess forecasts from two models: Shapiro and Smoothed Seismicity (SaSS) and Hydraulics and Seismics (HySei). These models incorporate a different mix of physics-based elements and stochastic representation of the induced sequences. Our results show that neither model is fully superior to the other. Generally, HySei forecasts the seismicity rate better after shut-in, but is only mediocre at forecasting the spatial distri...

  5. Seismicity of the Jalisco Block

    Nunez-Cornu, F. J.; Rutz, M.; Camarena-Garcia, M.; Trejo-Gomez, E.; Reyes-Davila, G.; Suarez-Plascencia, C.


    In April 2002 began to transmit the stations of the first phase of Jalisco Telemetric Network located at the northwest of Jalisco Block and at the area of Volcan de Fuego (Colima Volcano), in June were deployed four additional MarsLite portable stations in the Bahia de Banderas area, and by the end of August one more portable station at Ceboruco Volcano. The data of these stations jointly with the data from RESCO (Colima Telemetric Network) give us the minimum seismic stations coverage to initiate in a systematic and permanent way the study of the seismicity in this very complex tectonic region. A preliminary analysis of seismicity based on the events registered by the networks using a shutter algorithm, confirms several important features proposed by microseismicity studies carried out between 1996 and 1998. A high level of seismicity inside and below of Rivera plate is observed, this fact suggest a very complex stress pattern acting on this plate. Shallow seismicity at south and east of Bahia de Banderas also suggest a complex stress pattern in this region of the Jalisco Block, events at more than 30 km depth are located under the mouth of the bay and in face of it, a feature denominated Banderas Boundary mark the change of the seismic regime at north of this latitude (20.75°N), however some shallow events were located at the region of Nayarit.

  6. Four Forensic Entomology Case Studies: Records and Behavioral Observations on Seldom Reported Cadaver Fauna With Notes on Relevant Previous Occurrences and Ecology.

    Lindgren, Natalie K; Sisson, Melissa S; Archambeault, Alan D; Rahlwes, Brent C; Willett, James R; Bucheli, Sibyl R


    A yearlong survey of insect taxa associated with human decomposition was conducted at the Southeast Texas Applied Forensic Science (STAFS) facility located in the Center for Biological Field Studies of Sam Houston State University in Huntsville, TX. During this study, four insect-cadaver interactions were observed that represent previously poorly documented yet forensically significant interactions: Syrphidae maggots colonized a corpse in an aquatic situation; Psychodidae adults mated and oviposited on an algal film that was present on a corpse that had been recently removed from water; several Panorpidae were the first insects to feed upon a freshly placed corpse in the autumn; and a noctuid caterpillar was found chewing and ingesting dried human skin. Baseline knowledge of insect-cadaver interactions is the foundation of forensic entomology, and unique observations have the potential to expand our understanding of decomposition ecology.

  7. Vitamin D deficiency in medical patients at a central hospital in Malawi: a comparison with TB patients from a previous study.

    Yamikani Mastala

    Full Text Available OBJECTIVES: To determine the prevalence of vitamin D deficiency (VDD in adult medical, non-tuberculous (non-TB patients. To investigate associations with VDD. To compare the results with a similar study in TB patients at the same hospital. DESIGN: Cross-sectional sample. SETTING: Central hospital in Malawi. PARTICIPANTS: Adult non-TB patients (n = 157, inpatients and outpatients. OUTCOME MEASURES: The primary outcome was the prevalence of VDD. Potentially causal associations sought included nutritional status, in/outpatient status, HIV status, anti-retroviral therapy (ART and, by comparison with a previous study, a diagnosis of tuberculosis (TB. RESULTS: Hypovitaminosis D (≤75 nmol/L occurred in 47.8% (75/157 of patients, 16.6% (26/157 of whom had VDD (≤50 nmol/L. None had severe VDD (≤25 nmol/L. VDD was found in 22.8% (23/101 of in-patients and 5.4% (3/56 of out-patients. In univariable analysis in-patient status, ART use and low dietary vitamin D were significant predictors of VDD. VDD was less prevalent than in previously studied TB patients in the same hospital (68/161 = 42%. In multivariate analysis of the combined data set from both studies, having TB (OR 3.61, 95%CI 2.02-6.43 and being an in-patient (OR 2.70, 95%CI 1.46-5.01 were significant independent predictors of VDD. CONCLUSIONS: About half of adult medical patients without TB have suboptimal vitamin D status, which is more common in in-patients. VDD is much more common in TB patients than non-TB patients, even when other variables are controlled for, suggesting that vitamin D deficiency is associated with TB.

  8. New Insight on the Increasing Seismicity during Tenerife's 2004 Volcanic Reactivation

    Cerdeña, I Domínguez; Rivera, L; 10.1016/j.jvolgeores.2011.06.005


    Starting in April 2004, unusual seismic activity was observed in the interior of the island of Tenerife (Canary Islands, Spain) with much evidence pointing to a reawakening of volcanic activity. This seismicity is now analyzed with techniques unprecedented in previous studies of this crisis. The 200 earthquakes located onshore during 2004 and 2005 have been classified by cross-correlation, resulting in a small number of significant families. The application of a relative location algorithm (hypoDD) revealed important features about the spatial distribution of the earthquakes. The seismic catalogue has been enhanced with more than 800 additional events, detected only by the closest seismic station. These events were assigned to families by correlation and as a consequence their hypocentral location and magnitude were estimated by comparing them to the earthquakes of each family. The new catalogue obtained by these methods identifies two major seismogenic zones, one to the northwest and the other to the southwe...

  9. Myocardial adaptation to high-intensity (interval) training in previously untrained men with a longitudinal cardiovascular magnetic resonance imaging study (Running Study and Heart Trial).

    Scharf, Michael; Schmid, Axel; Kemmler, Wolfgang; von Stengel, Simon; May, Matthias S; Wuest, Wolfgang; Achenbach, Stephan; Uder, Michael; Lell, Michael M


    To prospectively evaluate whether short-term high-intensity (interval) training (HI(I)T) induces detectable morphological cardiac changes in previously untrained men in cardiovascular magnetic resonance imaging. Eighty-four untrained volunteers were randomly assigned to a HI(I)T group (n=42; 44.1±4.7 years) or an inactive control group (n=42; 42.3±5.6 years). HI(I)T focused on interval runs (intensity: 95%-105% of individually calculated heart rate at the anaerobic threshold). Before and after 16 weeks, all subjects underwent physiological examination, stepwise treadmill test with blood lactate analysis, and contrast-enhanced cardiovascular magnetic resonance imaging (cine, tagging, and delayed enhancement). Indexed left ventricular (LV) and right ventricular (RV) volume (LV, 77.1±8.5-83.9±8.6; RV, 80.5±8.5-86.6±8.1) and mass (LV, 58.2±6.4-63.4±8.1; RV, 14.8±1.7-16.1±2.1) significantly increased with HI(I)T. Changes in LV and RV morphological parameters with HI(I)T were highly correlated with an increase in maximal aerobic capacity (VO2max) and a decrease in blood lactate concentration at the anaerobic threshold. Mean LV and RV remodeling index of HI(I)T group did not alter with training (0.76 ±0.09 and 0.24±0.10 g/mL, respectively [P=0.97 and P=0.72]), indicating balanced cardiac adaptation. Myocardial circumferential strain decreased after HI(I)T within all 6 basal segments (anteroseptal, P=0.01 and anterolateral, PHeart Association, Inc.

  10. Biomechanical jumping differences among elite female handball players with and without previous anterior cruciate ligament reconstruction: a novel inertial sensor unit study.

    Setuain, Igor; Millor, Nora; González-Izal, Miriam; Gorostiaga, Esteban M; Gómez, Marisol; Alfaro-Adrián, Jesús; Maffiuletti, Nicola A; Izquierdo, Mikel


    Persistent biomechanical and jumping capacity alterations have been observed among female athletes who have sustained anterior cruciate ligament (ACL) injuries. The purpose of this study was to examine if biomechanical jumping differences persist among a cohort of elite female handball players with previous ACL reconstruction several years after return to top-level competition. In order to achieve this goal, a direct mechanics simplified analysis by using a single Inertial Sensor Unit (IU) was used. Twenty-one elite female (6 anterior cruciate ligament reconstructed and 15 uninjured control players) handball players were recruited and evaluated 6.0 ± 3.5 years after surgical anterior cruciate ligament reconstruction. Bilateral and unilateral vertical jumps were performed to evaluate the functional performance and a single inertial sensor unit was employed in order to collect 3D acceleration and 3D orientation data. Previously ACL-reconstructed analysed athletes demonstrated significant (p reconstruction. Identification of the encountered deficits through the use of an IU devise could provide clinicians with a new reliable tool for movement analysis in a clinical setting.

  11. Seismic properties of polyphase rocks

    Wang, Qin


    Knowledge about the seismic properties of polyphase rocks is fundamental for interpreting seismic refraction and reflection data and for establishing lithospheric structure and composition models. This study aims to obtain more precise relationships between seismic properties of rocks and controlling factors (e.g., pressure, temperature, mineralogical and chemical compositions, microstructure of rocks), particularly for those rocks imprinted by ultrahigh-pressure (UHP) metamorphism. These relationships will be very helpful to extrapolate calculated and measured seismic properties of rocks to depths of interest and to engender interpretations relevant to petrological composition and tectonic process. An Internet Database of Rock Seismic Properties (DRSP) was set up and a Handbook of Seismic Properties of Minerals, Rocks and Ores was published. They comprise almost all data available in the literature during the past 4 decades and can serve as a convenient, comprehensive and concise information source on physical properties of rocks to the earth sciences and geotechnical communities. Statistical results of the DRSP reveal the dependence of seismic properties on density, porosity, humidity, and mineralogical and chemical compositions. Using 16 different averaging methods, we calculated P-wave velocities of 696 dry samples according to the volume fraction and elastic constants of each constituent mineral. Although only 22 common minerals were taken into account in the computation, the calculated P-wave velocities agree well with laboratory values measured at about 300 MPa, where most microcracks are closed and the mean Vp of a polymineralic rock is exclusively controlled by its modal composition. However, none of these mixture rules can simultaneously fit measured P-wave velocities for all lithologies or at all pressures. Therefore, more prudence is required in selecting an appropriate mixture rule for calculation of seismic velocities of different rock types.

  12. Advancing New 3D Seismic Interpretation Methods for Exploration and Development of Fractured Tight Gas Reservoirs

    James Reeves


    In a study funded by the U.S. Department of Energy and GeoSpectrum, Inc., new P-wave 3D seismic interpretation methods to characterize fractured gas reservoirs are developed. A data driven exploratory approach is used to determine empirical relationships for reservoir properties. Fractures are predicted using seismic lineament mapping through a series of horizon and time slices in the reservoir zone. A seismic lineament is a linear feature seen in a slice through the seismic volume that has negligible vertical offset. We interpret that in regions of high seismic lineament density there is a greater likelihood of fractured reservoir. Seismic AVO attributes are developed to map brittle reservoir rock (low clay) and gas content. Brittle rocks are interpreted to be more fractured when seismic lineaments are present. The most important attribute developed in this study is the gas sensitive phase gradient (a new AVO attribute), as reservoir fractures may provide a plumbing system for both water and gas. Success is obtained when economic gas and oil discoveries are found. In a gas field previously plagued with poor drilling results, four new wells were spotted using the new methodology and recently drilled. The wells have estimated best of 12-months production indicators of 2106, 1652, 941, and 227 MCFGPD. The latter well was drilled in a region of swarming seismic lineaments but has poor gas sensitive phase gradient (AVO) and clay volume attributes. GeoSpectrum advised the unit operators that this location did not appear to have significant Lower Dakota gas before the well was drilled. The other three wells are considered good wells in this part of the basin and among the best wells in the area. These new drilling results have nearly doubled the gas production and the value of the field. The interpretation method is ready for commercialization and gas exploration and development. The new technology is adaptable to conventional lower cost 3D seismic surveys.

  13. A longitudinal study of relationships between previous academic achievement, emotional intelligence and personality traits with psychological health of medical students during stressful periods.

    Yusoff, Muhamad Saiful Bahri; Esa, Ab Rahman; Mat Pa, Mohamad Najib; Mey, See Ching; Aziz, Rosniza Abdul; Abdul Rahim, Ahmad Fuad


    There is considerable evidence that emotional intelligence, previous academic achievement (i.e. cumulative grade point average (GPA)) and personality are associated with success in various occupational settings. This study evaluated the relationships of these variables with psychological health of first year medical students during stressful periods. A 1-year prospective study was done with students accepted into the School of Medical Sciences, Universiti Sains Malaysia. Information on emotional intelligence, GPA and personality traits were obtained prior to admission. The validated Universiti Sains Malaysia Emotional Quotient Inventory and Universiti Sains Malaysia Personality Inventory were used to measure emotional intelligence and personality traits, respectively. Stress, anxiety and depression were measured by the 21-item Depression Anxiety Stress Scale during the end-of-course (time 1) and final (time 2) examinations. At the less stressful period (time 1), stress level was associated with agreeableness and the final GPA, anxiety level was associated with emotional control and emotional conscientiousness and depression level was associated with the final GPA and extraversion. At the more stressful period (time 2), neuroticism associated with stress level, anxiety level was associated with neuroticism and emotional expression, and depression level was associated with neuroticism. This study found that neuroticism was the strongest associated factor of psychological health of medical students during their most stressful testing period. Various personality traits, emotional intelligence and previous academic performance were associated factors of psychological health during a less stressful period. These data suggest that early identification of medical students who are vulnerable to the stressful environment of medical schools might help them maintain psychological well-being during medical training.

  14. seismicity and seismotectonics of Libya

    Ben Suleman, abdunnur


    Libya, located at the central Mediterranean margin of the African shield, underwent many episodes of orogenic activity that shaped its geological setting. The present day deformation of Libya is the result of the Eurasia-Africa continental collision. The tectonic evolution of Libya has yielded a complex crustal structure that is composed of a series of basins and uplifts. This study aims to explain in detail the seismicity and seismotectonics of Libya using new data recorded by the recently established Libyan National Seismograph Network (LNSN) incorporating other available geophysical and geological information. Detailed investigations of the Libyan seismicity indicates that Libya has experienced earthquakes of varying magnitudes The seismic activity of Libya shows dominant trends of Seismicity with most of the seismic activity concentrated along the northern coastal areas. Four major clusters of Seismicity were quit noticeable. Fault plane solution was estimated for 20 earthquakes recorded by the Libyan National Seismograph Network in northwestern and northeastern Libya. Results of fault plane solution suggest that normal faulting was dominant in the westernmost part of Libya; strike slip faulting was dominant in northern-central part of Libya. The northern-eastern part of the country suggests that dip-dip faulting were more prevalent.

  15. Case study of seismic performance assessment of irregular RC buildings: hospital structure of Avezzano (L'Aquila, Italy)

    Ferraioli, Massimiliano


    Most published studies on inelastic earthquake response of non-symmetric buildings are based on simplified inelastic, highly idealized models, while general conclusions regarding the inelastic torsional response of multistory building are still lacking. This paper aims to provide a useful contribution in the study of the torsional response of real irregular buildings. To this aim, the manuscript reports the comprehensive study on the seismic vulnerability of an irregular RC building: the hospital building of Avezzano (L'Aquila Italy). For this multi-story building, which is irregular in both plan and elevation, the application of nonlinear static evaluation procedures is by no means straightforward. The study proposes a nonlinear static procedure based on pushover analysis under the multimodal distribution of lateral loads and a capacity spectrum method. This pushover procedure accounts for mass distribution, higher modes contribution and mode-shapes correlation. Furthermore, due to its non-iterative feature, it avoids problems of non-convergence and multiple solutions of the conventional capacity spectrum method. Applied to a real case study, the procedure is used to investigate, in a 3D plan irregular building, the sensitivity of torsional inelastic response to lateral force distribution, higher modes contribution, accidental eccentricity and controlled point for monitoring the target displacement.

  16. Study on the genesis of karstic collapse column and characteristics of high resolution seismic data in one coal field

    ZHANG Shao-hong; LIN Chang-rong


    On the standpoint of the disaster prevention from water inrush,discussed the genesis and geologic condition of karstic collapse column in one coal field,analyzed the geophysical characteristics of karstic collapse column by using high resolution 3D seismic data.It shows the effective result of the technology of high resolution 3D seismic prospecting in the exploration of the karstic collapse column,and presents some prediction methods and prevention measures.

  17. Study to Determine Seismic Response of Sonic Boom-Coupled Rayleigh Waves


    are compiled from the microtremor measurements carried out by Instituto de Ingenieria , UNAM and scientists from Japan (for a total of 181 sites...the accelerographs operated by Instituto de Ingenieria , UNAM. Using this new data and results from the analysis of previous accelerograms we present

  18. Study on the Properties of TiN Coatings on Previously Ion-Implanted Pure Magnesium Surface by MEVVA Ion Implantation

    ZHOU Hai; CHEN Fei; WANG Jian-ping


    A metal vapor vacuum arc (MEVVA) is used in ion implantation for substrate preparation before the deposition process which would ensure the improvement of mechanical properties of the coating.Ti ion is implanted into pure magnesium surface by MEVVA implanter operated with a modified cathode.Implanting energy is kept at 45 keV and dose is set at 3×1017 cm-2.TiN coatings are deposited by magnetically filtered vacuum-arc plasma source on unimplanted and previously implanted substrates.Microstructure and phase composition are analysed using scanning electron microscopy (SEM) and X-ray diffraction (XRD).The property of corrosion resistance of TiN coatings was studied by CS300P electrochemistry-corrosion workstation,and the main impact factor of the corrosion resistance was also analyzed.

  19. Phase II study of a 3-day schedule with topotecan and cisplatin in patients with previously untreated small cell lung cancer and extensive disease

    Sorensen, M.; Lassen, Ulrik Niels; Jensen, Peter Buhl;


    and cisplatin are needed. The aim of this phase II study was to establish the response rate and response duration in chemo-naive patients with SCLC receiving a 3-day topotecan and cisplatin schedule. METHODS: Simons optimal two-stage design was used. Patients with previously untreated extensive disease SCLC......, adequate organ functions and performance status less than 3 were eligible. Topotecan (2.0 mg/m, intravenously) was administered on days 1 to 3 with cisplatin (50 mg/m, intravenously) on day 3 every 3 weeks for a total of six cycles. RESULTS: Forty-three patients received 219 cycles of chemotherapy. Median.......3-7.7), respectively. CONCLUSION: Three-day topotecan with cisplatin on day 3 is active and safe in extensive disease SCLC. An ongoing phase III randomized trial compares this combination to standard treatment Udgivelsesdato: 2008/8...


    Hausmann, Jennifer C; Wack, Allison N; Allender, Matthew C; Cranfield, Mike R; Murphy, Kevin J; Barrett, Kevin; Romero, Jennell L; Wellehan, James F X; Blum, Stella A; Zink, M Christine; Bronson, Ellen


    The Maryland Zoo in Baltimore experienced an outbreak of Frog virus-3 (FV3)-like ranavirus during the summer of 2011, during which 14 of 27 (52%) of its captive eastern box turtles (Terrapene carolina carolina) survived. To assess survival, immunity, and viral shedding, an experimental challenge study was performed in which the surviving, previously infected turtles were reinfected with the outbreak strain of FV3-like ranavirus. Seven turtles were inoculated with virus intramuscularly and four control turtles received saline intramuscularly. The turtles were monitored for 8 wk with blood and oral swabs collected for quantitative polymerase chain reaction (qPCR). During that time, one of seven (14%) inoculated turtles and none of the controls (0%) died; there was no significant difference in survival. Clinical signs of the inoculated turtles, except for t