International Journal of Geophysics最新文献_第8页

Focal Mechanisms of Mw 6.3 Aftershocks from Waveform Inversions, Phayao Fault Zone, Northern Thailand 泰国北部帕瑶断裂带波形反演的6.3级余震震源机制

IF 1.1

International Journal of Geophysics Pub Date : 2017-05-24 DOI: 10.1155/2017/9059825

Kasemsak Saetang

{"title":"Focal Mechanisms of Mw 6.3 Aftershocks from Waveform Inversions, Phayao Fault Zone, Northern Thailand","authors":"Kasemsak Saetang","doi":"10.1155/2017/9059825","DOIUrl":"https://doi.org/10.1155/2017/9059825","url":null,"abstract":"The focal mechanisms of Mw 6.3 aftershocks, Chiang Rai Province, Northern Thailand, were determined by using a multistation waveform inversion. Three aftershocks were selected and their waveforms were inverted for moment tensor calculation. Waveform inversions were derived from three broadband stations with three components and epicentral distances less than 250 km after all seismic stations were considered. The deviatoric moment tensor inversion was used for focal mechanism calculations. Band-pass filtering in the range of 0.03–0.15 Hz was selected for reducing low- and high-frequency noise. Source positions were created by using a single-source inversion and a grid-search method computed to optimize the waveform match. The results showed stable moment tensors and fault geometries with the southwest azimuth in the northern part of the Payao Fault Zone (PFZ) with depths shallower than 10 km. Left-lateral strike-slip with a reverse component was detected. The tectonics of the PFZ is constrained by fault-plane solutions of earthquakes. WSW directional strikes are observed in the northern part of the PFZ.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"95 1","pages":"1-7"},"PeriodicalIF":1.1,"publicationDate":"2017-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2017/9059825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41307509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Variability and Trend of Annual Maximum Daily Rainfall in Northern Algeria 阿尔及利亚北部年最大日降雨量的变率和趋势

IF 1.1

International Journal of Geophysics Pub Date : 2016-07-27 DOI: 10.1155/2016/6820397

A. N. Ghenim, A. Megnounif

{"title":"Variability and Trend of Annual Maximum Daily Rainfall in Northern Algeria","authors":"A. N. Ghenim, A. Megnounif","doi":"10.1155/2016/6820397","DOIUrl":"https://doi.org/10.1155/2016/6820397","url":null,"abstract":"The daily rainfall dataset of 35 weather stations covering the north of Algeria was studied for a period up to 43 years, recorded after 1970s. The variability and trends in annual maximum daily rainfall (AMDR) time series and their contributions in annual rainfall (AR) were investigated. The analysis of the series was based on statistical characteristics, Burn’s seasonality procedure, Mann-Kendall test, and linear regression technique. The contribution of the AMDR to AR analysis was subjected to both the Buishand test and the double mass curve technique. The AMDR characteristics reveal a strong temporal irregularity and have a wide frequency of occurrence in the months of November and December while the maximum intensity occurred in October. The observed phenomenon was so irregular that there was no dominant season and the occurrence of extreme event can arrive at any time of the year. The AMDR trends showed that only six of 35 stations have significant trend. For other stations, no clear trend was highlighted. This result was confirmed by the linear regression procedure. On the contrary, the contribution of AMDR in annual totals exhibited a significant increasing trend for 57% of the sites studied with a growth rate of up to 50%.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-11"},"PeriodicalIF":1.1,"publicationDate":"2016-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/6820397","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64490770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 25

Integrated Resistivity and Ground Penetrating Radar Observations of Underground Seepage of Hot Water at Blawan-Ijen Geothermal Field 布拉万-依真地热田热水地下渗流的电阻率和探地雷达综合观测

IF 1.1

International Journal of Geophysics Pub Date : 2016-07-13 DOI: 10.1155/2016/6034740

S. Maryanto, Ika Karlina Laila Nur Suciningtyas, C. N. Dewi, A. Rachmansyah

{"title":"Integrated Resistivity and Ground Penetrating Radar Observations of Underground Seepage of Hot Water at Blawan-Ijen Geothermal Field","authors":"S. Maryanto, Ika Karlina Laila Nur Suciningtyas, C. N. Dewi, A. Rachmansyah","doi":"10.1155/2016/6034740","DOIUrl":"https://doi.org/10.1155/2016/6034740","url":null,"abstract":"Geothermal resource investigation was accomplished for Blawan-Ijen geothermal system. Blawan geothermal field which located in the northern part of Ijen caldera presents hydrothermal activity related with Pedati fault and local graben. There were about 21 hot springs manifestations in Blawan-Ijen area with calculated temperature about 50°C. We have performed several geophysical studies of underground seepage of hot water characterization. The geoelectric resistivity and GPR methods are used in this research because both of them are very sensitive to detect the presence of hot water. These preliminary studies have established reliable methods for hydrothermal survey that can accurately investigate the underground seepage of hot water with shallow depth resolution. We have successfully identified that the underground seepage of hot water in Blawan geothermal field is following the fault direction and river flow which is evidenced by some hot spring along the Banyu Pahit river with resistivity value less than 40 Ωm and medium conductivity.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-14"},"PeriodicalIF":1.1,"publicationDate":"2016-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/6034740","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64455046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Planetary Sciences, Geodynamics, Impacts, Mass Extinctions, and Evolution: Developments and Interconnections 行星科学、地球动力学、撞击、大灭绝和进化:发展和相互联系

IF 1.1

International Journal of Geophysics Pub Date : 2016-06-16 DOI: 10.1155/2016/4703168

J. Urrutia‐Fucugauchi, L. Pérez‐Cruz

引用次数: 2

Influence of Error in Estimating Anisotropy Parameters on VTI Depth Imaging 各向异性参数估计误差对VTI深度成像的影响

IF 1.1

International Journal of Geophysics Pub Date : 2016-05-15 DOI: 10.1155/2016/2848750

S. Y. M. Alashloo, D. Ghosh, Y. Bashir, W. Ismail

{"title":"Influence of Error in Estimating Anisotropy Parameters on VTI Depth Imaging","authors":"S. Y. M. Alashloo, D. Ghosh, Y. Bashir, W. Ismail","doi":"10.1155/2016/2848750","DOIUrl":"https://doi.org/10.1155/2016/2848750","url":null,"abstract":"Thin layers in sedimentary rocks lead to seismic anisotropy which makes the wave velocity dependent on the propagation angle. This aspect causes errors in seismic imaging such as mispositioning of migrated events if anisotropy is not accounted for. One of the challenging issues in seismic imaging is the estimation of anisotropy parameters which usually has error due to dependency on several elements such as sparse data acquisition and erroneous data with low signal-to-noise ratio. In this study, an isotropic and anelliptic VTI fast marching eikonal solvers are employed to obtain seismic travel times required for Kirchhoff depth migration algorithm. The algorithm solely uses compressional wave. Another objective is to study the influence of anisotropic errors on the imaging. Comparing the isotropic and VTI travel times demonstrates a considerable lateral difference of wavefronts. After Kirchhoff imaging with true anisotropy, as a reference, and with a model including error, results show that the VTI algorithm with error in anisotropic models produces images with minor mispositioning which is considerable for isotropic one specifically in deeper parts. Furthermore, over- or underestimating anisotropy parameters up to 30 percent are acceptable for imaging and beyond that cause considerable mispositioning.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-6"},"PeriodicalIF":1.1,"publicationDate":"2016-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/2848750","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64298782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Hydromagnetic Stability of Metallic Nanofluids (Cu-Water and Ag-Water) Using Darcy-Brinkman Model 基于Darcy-Brinkman模型的金属纳米流体(Cu-Water和Ag-Water)的磁稳定性

IF 1.1

International Journal of Geophysics Pub Date : 2016-04-14 DOI: 10.1155/2016/5864203

J. Ahuja, U. Gupta, R. K. Wanchoo

{"title":"Hydromagnetic Stability of Metallic Nanofluids (Cu-Water and Ag-Water) Using Darcy-Brinkman Model","authors":"J. Ahuja, U. Gupta, R. K. Wanchoo","doi":"10.1155/2016/5864203","DOIUrl":"https://doi.org/10.1155/2016/5864203","url":null,"abstract":"Thermal convection of a nanofluid layer in the presence of imposed vertical magnetic field saturated by a porous medium is investigated for both-free, rigid-free, and both-rigid boundaries using Darcy-Brinkman model. The effects of Brownian motion and thermophoretic forces due to the presence of nanoparticles and Lorentz’s force term due to the presence of magnetic field have been considered in the momentum equations along with Maxwell’s equations. Keeping in mind applications of flow through porous medium in geophysics, especially in the study of Earth’s core, and the presence of nanoparticles therein, the hydromagnetic stability of a nanofluid layer in porous medium is considered in the present formulation. An analytical investigation is made by applying normal mode technique and Galerkin type weighted residuals method and the stability of Cu-water and Ag-water nanofluids is compared. Mode of heat transfer is through stationary convection without the occurrence of oscillatory motions. Stability of the system gets improved appreciably by raising the Chandrasekhar number as well as Darcy number whereas increase in porosity hastens the onset of instability. Further, stability of the system gets enhanced as we proceed from both-free boundaries to rigid-free and to both-rigid boundaries.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-9"},"PeriodicalIF":1.1,"publicationDate":"2016-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/5864203","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64443251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Estimate for Southwest China 西南地区预测

IF 1.1

International Journal of Geophysics Pub Date : 2016-03-13 DOI: 10.1155/2016/9305095

Yan Yu, W. Silva, Bob Darragh, Xiaojun Li

{"title":"Estimate for Southwest China","authors":"Yan Yu, W. Silva, Bob Darragh, Xiaojun Li","doi":"10.1155/2016/9305095","DOIUrl":"https://doi.org/10.1155/2016/9305095","url":null,"abstract":"Several methods were used to estimate from site profiles with borehole depths of about 20 m for the strong-motion stations located in Southwest China. The methods implemented include extrapolation (constant and gradient), Geomatrix Site Classification correlation with shear-wave velocity, and remote sensing (terrain and topography). The gradient extrapolation is the preferred choice of this study for sites with shear-wave velocity profile data. However, it is noted that the coefficients derived from the California data set are not applicable to sites in Southwest China. Due to the scarcity of borehole profiles data with depth of more than 30 m in Southwest China, 73 Kiknet profiles were used to generate new coefficients for gradient extrapolation. Fortunately, these coefficients provide a reasonable estimate of for sites in Southwest China. This study showed could be estimated by the time-average shear-wave velocity (average slowness) of only 10 meters of depth. Furthermore, a median estimate based upon Geomatrix Classification is derived from the results of the gradient extrapolation using a regional calibration of the Geomatrix Classification with . The results of this study can be applied to assign to the sites without borehole data in Southwest China.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-11"},"PeriodicalIF":1.1,"publicationDate":"2016-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/9305095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64608259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Reducing Magnetic Noise of an Unmanned Aerial Vehicle for High-Quality Magnetic Surveys 为实现高质量磁测量，降低无人机磁噪声

IF 1.1

International Journal of Geophysics Pub Date : 2016-03-09 DOI: 10.1155/2016/4098275

B. Sterligov, S. Cherkasov

引用次数: 22

3D Gravity Modeling of Complex Salt Features in the Southern Gulf of Mexico 墨西哥湾南部复杂盐层特征的三维重力模拟

IF 1.1

International Journal of Geophysics Pub Date : 2016-03-08 DOI: 10.1155/2016/1702164

Mauricio Nava-Flores, C. Ortiz-Alemán, M. Orozco-del-Castillo, J. Urrutia‐Fucugauchi, A. Rodríguez-Castellanos, C. Couder-Castañeda, A. Trujillo-Alcantara

引用次数: 7

Discovery of Naturally Etched Fission Tracks and Alpha-Recoil Tracks in Submarine Glasses: Reevaluation of a Putative Biosignature for Earth and Mars 海底玻璃中自然蚀刻裂变轨迹和α -反冲轨迹的发现:对地球和火星假定生物特征的重新评估

IF 1.1

International Journal of Geophysics Pub Date : 2016-02-17 DOI: 10.1155/2016/2410573

J. E. French, D. Blake

{"title":"Discovery of Naturally Etched Fission Tracks and Alpha-Recoil Tracks in Submarine Glasses: Reevaluation of a Putative Biosignature for Earth and Mars","authors":"J. E. French, D. Blake","doi":"10.1155/2016/2410573","DOIUrl":"https://doi.org/10.1155/2016/2410573","url":null,"abstract":"Over the last two decades, conspicuously “biogenic-looking” corrosion microtextures have been found to occur globally within volcanic glass of the in situ oceanic crust, ophiolites, and greenstone belts dating back to ~3.5 Ga. These so-called “tubular” and “granular” microtextures are widely interpreted to represent bona fide microbial trace fossils; however, possible nonbiological origins for these complex alteration microtextures have yet to be explored. Here, we reevaluate the origin of these enigmatic microtextures from a strictly nonbiological standpoint, using a case study on submarine glasses from the western North Atlantic Ocean (DSDP 418A). By combining petrographic and SEM observations of corrosion microtextures at the glass-palagonite interface, considerations of the tectonic setting, measurement of U and Th concentrations of fresh basaltic glass by ICP-MS, and theoretical modelling of the present-day distribution of radiation damage in basaltic glass caused by radioactive decay of U and Th, we reinterpret these enigmatic microtextures as the end product of the preferential corrosion/dissolution of radiation damage (alpha-recoil tracks and fission tracks) in the glass by seawater, possibly combined with pressure solution etch-tunnelling. Our findings have important implications for geomicrobiology, astrobiological exploration of Mars, and understanding of the long-term breakdown of nuclear waste glass.","PeriodicalId":45602,"journal":{"name":"International Journal of Geophysics","volume":"2016 1","pages":"1-50"},"PeriodicalIF":1.1,"publicationDate":"2016-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2016/2410573","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64271784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10