地球物理学报最新文献

{"title":"Applications and challenges of near surface geophysics in geotechnical engineering","authors":"Chih‐Ping Lin, Chun-Hung Lin, Po-Lin Wu, Hsin-Chang Liu, Ying-Chun Hung","doi":"10.6038/CJG20150806","DOIUrl":"https://doi.org/10.6038/CJG20150806","url":null,"abstract":"","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"256 1","pages":"2664-2680"},"PeriodicalIF":1.4,"publicationDate":"2015-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78226339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends of glacial mass changes in High Asia from satellite gravity observations","authors":"Chuandong Zhu, Yang Lu, Hongling Shi, Zizhan Zhang, Z. Du, Chunchun Gao","doi":"10.6038/CJG20150309","DOIUrl":"https://doi.org/10.6038/CJG20150309","url":null,"abstract":"","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"793-801"},"PeriodicalIF":1.4,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71078625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ice sheet mass balance in Antarctica measured by GRACE and its uncertainty","authors":"Chunchun Gao, Yang Lu, Zizhan Zhang, Hongling Shi, Chuandong Zhu","doi":"10.6038/CJG20150308","DOIUrl":"https://doi.org/10.6038/CJG20150308","url":null,"abstract":"As a critical component of the cryosphere,the Antarctic Ice Sheet(AIS)has strongconnection with the sea level change and global climate change.Accurate quantification of the current spatial and temporal mass changes of AIS is very important to improve our understanding and prediction of its response and contribution to global change.The Gravity Recovery and Climate Experiment(GRACE)mission has provided new and useful observations to detect AIS mass balance since its launch in March 2002.There are significant differences among the GRACE estimates of the total mass change.The big difference is due in part to considerable uncertainty in the accuracy of glacial isostatic adjustment(GIA)signals,and also due to use of different time spans,different versions of GRACE products and different GRACE post-processing methods.Using 124 monthly GRACE gravity field solutions of Release 5(RL05)produced at the Center for Space Research(CSR)of the University of Texas,Austin,spanning the interval from January of 2003 through December of 2013,the mass balance of AIS is estimated by two postprocessing ways:the optimizing averaging kernel method(also named VW)and the combined filter method(the first step is called P5M11 decorrelation filter to remove correlated noise by fitting and subtracting a fifth-order polynomial to even and odd coefficient pairs at spherical harmonic orders eleven and above,the second involves smoothing with a 250 km Gaussian filter).A detailed error analysis is provided including consideration of leakage-in,leakage-out,and errors in modeling mass variations of the atmosphere,ocean and GIA.In addition,a statistical model selection criterion is employed in computation of trends from mass variation time series,and the impact of K1 tidal alias is analyzed.The results reveal that during 2003—2013,the total mass of the ice sheet decreased significantly at change rates of-163±50,-129±41and-81±27Gt/a for three GIA models:GW13,IJ05,W12 a.There was a distinct region with mass loss in the Amundsen Sea Embayment of West Antarctic ice sheet and the Northern Antarctic Peninsula,while an increasing mass gain was concentrated in the Dronning Maud Land and the Enderby Land of East Antarctic ice sheet.Furthermore,we use hypotheses testing and information criteria evaluation to select the best trend model fitting together with sinusoidal functions of annual(365.0-d)and semi-annual(181.0-d)signals and the S2(161.0-d),K1(2725.4-d)and K2(1362.7-d)tidal aliases.We found that K1 tidal alias has a potential to falsify the acceleration estimates.Although it is not good enough to confirm the K1 tidal alias based on an eleven-year time-series,the impact of K1 tidal alias deserves further notice.By comparing the quantities of total mass balance computed by the two different processing methods and three different GIA models in the Antarctica,we find that the differences are less than 15Gt/a between two processing methods,but the largest difference is about 80 Gt/a between di","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"780-792"},"PeriodicalIF":1.4,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71078606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"澳大利亚悉尼 Long Reef Beach 中新世古土壤岩石磁学特征及环境意义","authors":"Tao Wang, Hu Guo, Xiuming Liu, Bin Lü, Xue-Gang Mao, Zi-Bo Zhou, Changhui Wen, Shun-Min Hou, Long-Jian Su","doi":"10.6038/CJG20150322","DOIUrl":"https://doi.org/10.6038/CJG20150322","url":null,"abstract":"","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"971-981"},"PeriodicalIF":1.4,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71078677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental research on the effects of crack density based on synthetic sandstones contain controlled fractures","authors":"P. Ding, B. Di, Jianxin Wei, Xiang-Yang Li","doi":"10.6038/CJG20150425","DOIUrl":"https://doi.org/10.6038/CJG20150425","url":null,"abstract":"Fracture development and distribution in underground rocks have strong influence on rock properties, understanding the fracture system is critical to the oil and gas reservoir detection and production, groundwater resource, underground wastes storage, mining, seismology and CO2 capture and storage.Due to the complex fracture distribution and geometry in nature rocks, the lack of information about fracture parameters (fracture density, length and thickness) makes the nature rock cannot be used in laboratory experiments. Rock physics experiments require the controlled and known fracture parameters and orientation in rock samples, thus synthetic samples were used to represent fractured rocks in several previous studies. However, the fractures were represented by other week material, such as silica rubber imbedded in epoxy solid, to simulate the fractured rocks in previous studies. The materials used to construct the samples (Lucite, silica rubber, sand bonded by epoxy) were very different from nature rocks, the solid representing background matrix and the week material representing fractures have no porous and fracture space and saturated fluids. In this study, we use new construction method based on material science progress to build synthetic samples which have similar mineral component, porous structure, cementation as nature rocks. The synthetic rock containing controlled fracture geometry provides a different way to create fractured rocks to observe the seismic anisotropy influenced by fracture parameters and fluids. The synthetic rocks are tested under high pressure to observe the pressure sensitivity, and SEM is used to observe the porous structure and fractures distrubution. We build a set of synthetic rocks to observe the effect of fractures upon seismic wave velocity and anisotropy. The samples are measured with 0.5 MHz transducers. P and S wave velocity in different propagation directions of these four samples are measured when saturated by air and water.The experimental results can help in investigating the relationship between fracture density and P and S wave anisotropy in fractured reservoirs. The measurement results show that the P wave velocity and anisotropy is significantly influenced by saturating fluid. Shear wave velocity, shear wave splitting and shear wave anisotropy are less sensitive to saturating fluid but significantly affected by fracture density. P wave velocities in perpendicular direction show significant influences of fracture, the velocity decreases as the fracture density increases. Shear wave velocity in perpendicular direction decreases with the increasing fracture density, the difference between fast shear wave and slow shear wave velocity is smaller in this direction. However the slow shear wave velocity is more sensitive to fracture density than fast shear wave velocity in parallel direction, thus the difference of fast and slow shear wave velocity in parallel direction increases as the fracture density increa","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71078739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Distribution Characters of the Stratospheric Brewer‐Dobson Circulation Inferred from Era‐Interim","authors":"Wang Wei-guo, Yang Fang-yuan, Wang Hao-yue, Y. Tao, Y. Ke, LI Shu-kun, Fan Wen-Xuan","doi":"10.1002/CJG2.20152","DOIUrl":"https://doi.org/10.1002/CJG2.20152","url":null,"abstract":"The spatial-temporal distribution characters of trace gases in the stratosphere and troposphere are affected by the Brewer-Dobson (BD) circulation. Understanding the distribution characters of the BD circulation is very important for further studying the influence of stratosphere and troposphere exchange and forecasting the global climate change. The BD circulation is described as the Lagrangian-mean circulation, which is difficult to diagnose directly from meteorological observations. The methods of the transformed Eulerian-mean (TEM) equations and integrating residual meridional velocity in the vertical were used to analyze the spatial-temporal distribution characters of the BD circulation based on the ERA-Interim reanalysis data at 12:00 UTC for 1979–2011. We further compared the distribution characters of BD circulation with the result calculated by the method of DC (Downward Control) principle and studied the relationship between the stratospheric zonal mean temperature and BD circulation. The BD circulation was calculated using ERA-Interim reanalysis data for 1979–2011 by integrating residual meridional velocity in the vertical direction. The results show that the ascending centers of BD circulation varied with seasons. It ascended at 30°S in the stratosphere from December to February (DJF), while from June to August (JJA) it ascended between 25°N and 30°N. The circulation pattern in the winter hemisphere was stronger than the summer hemisphere. In March to May (MAM) and September to November (SON), the ascending centers were between equator to 5°N, and circulation were relatively symmetric between the two hemispheres. The maximum mass flux in the tropical and extratropical northern hemisphere appeared during DJF, and the minimum appeared during JJA. The mass flux in the extratropical southern hemisphere was just the opposite. Mass flux across the 100 hPa and 50 hPa pressure surface in the tropical and extratropical areas tended to decrease, and also varied obviously with the changing of season. The long-term trend of stratospheric zonal mean temperature was consistent with the long-term weakening trend of BD circulation, which indicates that the global BD circulation has been weakened. Meanwhile, the zonal mean temperature at different altitudes and latitudes varied with seasons. From the perspective of the global mass transportation, the stratospheric BD circulation has been weakened in the past 33 years, especially in the middle and lower stratosphere, which was consistent with the long-term trend of temperature. This weakened trend was consistent with the observations of stratospheric air and other model results. But the method of DC principle, GCMs model and other studies show that the stratospheric BD circulation has been enhanced in the past years. Using different methods and data would make the trend estimation of BD circulation unreliable. Therefore, further research is required to improve this estimation.","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"20-31"},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CJG2.20152","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51220380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Multi‐Scale Scratch Analysis Method for Quantitative Interpretation of Regional Gravity Fields","authors":"Yang Wen-cai, Sun Yan-yun, Hou Zunze, Yuan Chang-qing","doi":"10.1002/CJG2.20154","DOIUrl":"https://doi.org/10.1002/CJG2.20154","url":null,"abstract":"This paper presents new systematic methods of regional gravity data processing that combine theories based on multi-scale wavelet analysis, spectral analysis of potential fields, geophysical inversion, and information extraction. We call this data processing system as the multi-scale scratch analysis for delineation of crustal structures, deformation belts and division of continental tectonic units. The multi-scale scratch analysis contains four modules; they are spectral analysis for division of density layers, decomposition of the field by using wavelet transformation and multi-scale analysis, depth estimation and density inversion of decomposed gravity anomalies, and scratch analysis. The basic principles, application techniques and examples for each module are explained. As a complicated and sophisticated process, the multi-discipline research on regional geophysics from geophysical investigation to tectonic results requires combination of new methods and techniques coming from different disciplines, to build a wide and thick theoretic base for supporting the multi-discipline research. The multi-scale scratch analysis combines supporting bases coming from applied mathematics, geophysics, and information science respectively.","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"41-53"},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CJG2.20154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51220449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Terrain Evolution of China Seas and Land Since the Indo‐China Movement and Characteristics of the Stepped Landform","authors":"Zhang Xun-hua, Wang Zhong-lei, Hou Fang-hui, Yang Jin-yu, Guo Xing-Wei","doi":"10.1002/CJG2.20155","DOIUrl":"https://doi.org/10.1002/CJG2.20155","url":null,"abstract":"Terrain is the situation of the ground rising and falling, which is controlled by both the endogenetic and exogenic forces of the earth. The terrain reflects the internal structure, construction, and evolution of the curst. Free-air gravity anomalies are related to topography and geomorphology. It is considered that the curst that under mountains is thicker than that under plains by the equalization principle. There is a mirror image relationship between crust thickness and terrain relief. The map series of geology and geophysics of China seas and land include figures of tectonic framework and evolution of tectonic framework. The temporal evolution of the main blocks is studied in both of the maps, which elaborate the evolution of China's terrain as a “Seesaw”. This paper analyzes the geomorphological features by the free-air gravity anomaly map and Moho depth distribution map. In accordance with the principle of tectonic landform classification, the general characteristics of China seas and land is viewed as a whole which shows five terrain steps from west to east on the basis of three geomorphological ladders of Chinese land.","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"88 1","pages":"54-68"},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CJG2.20155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51220462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Borehole acoustic fields in porous formation with tilted thin fracture","authors":"Yang Shouguo, Xie Fu-li, Gong Dan, Zhang Cheng-guang, Zhang Bixing","doi":"10.6038/CJG20150128","DOIUrl":"https://doi.org/10.6038/CJG20150128","url":null,"abstract":"As the improvement of global oil and gas exploration,the fractural reservoir becomes one of the most important objects.The fractures complicatedly influence the array waveforms of logging because of the diversity distribution of fracture zone,which causes the recognition and evaluation become one of the most difficult problems in acoustic logging.In this paper,we research the acoustic field of the borehole surrounded by aporous formation with tilt fractures by numerical simulation,and also investigate the characteristics of borehole fields in the formations with different fracture parameters.We numerically simulate the acoustic fields excited by a point source in the borehole surrounded by aporous formation with tilt fractures using the 3-D staggered grid stress-velocity finite difference method.We design a non-uniform grid finite difference method in order to satisfy the computation of thin fractures,the precision and speed of calculation are improved significantly.We process the fluid inside fractures through setting the parameters of constitutive functions as fluid limitation,which uniforms the difference equations on the fluid-porous media boundary and makes the computation more flexible.We investigate and compare many parameters influencing on the array waveforms,such as fracture width,fracture zone width,tilt angle and permeability.By the computations and analysis of borehole acoustic fields in different conditions,we can get conclusions as follows:1.The fractures barely influence body waves because the fracture width is much less than the acoustic wavelength,but the reflected shear wave and reflected Stoneley wave still could exist when Stoneley wave goes through the fracture.2.When the fractures are horizontal,only reflected Stoneley wave can be observed if the source is low frequency(2.5kHz),while the reflected shear wave and reflected Stoneley wave both exist if the source is high frequency(5kHz and above).The amplitude of reflected Stoneley wave decreases when the width of fracture reduces,though the amplitude of reflected shear wave is unchanged.The reflected shear wave still exists when the fracture width reduces to 20 m.3.The density and width of fracture zone significantly influence the amplitude of reflected waves.When the density is small,the reflected waves are weak due to the low density causes the small fractures′interaction;as the density increasing,the reflected waves get stronger.4.When the fracture cross the borehole and tilt,the reflected shear wave disappears,however the reflected Stoneley wave still exists,this is good for testing tilt fractures.5.The attenuation of Stoneley waves increases along with the permeability increases.This causes the amplitude of inflected Stoneley waves on the fracture boundary decreases,so the reflected Stoneley wave could not be observed when the fractures are long away from source.In this paper,3-D non-uniform grid finite difference method is used to numerically simulate the acoustic field","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71078963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of the Natural Distribution of Carbon and Nutrients in the Ocean Based on the Global Ocean Carbon Cycle Model MOM4_L40","authors":"L. Qing-quan, Tan Juan, Wang Lanning, W. Min, Zhao Qi-Geng","doi":"10.1002/CJG2.20151","DOIUrl":"https://doi.org/10.1002/CJG2.20151","url":null,"abstract":"A global ocean carbon cycle circulation model which was developed by the National Climate Center, China Meteorological Administration is presented and the basic performance of this model is analyzed and evaluated in this paper. This model is a global three-dimensional (3D) ocean carbon cycle circulation model, with 40 layers in vertical direction, and biogeochemical processes developed on the basis of the global ocean circulation model MOM4 (Modular Ocean Model version 4) of the US Geophysical Fluid Dynamics Laboratory (GFDL), which is abbreviated as MOM4_L40 (Modular Ocean Model Version 4 with 40 Levels). This model has been integrated for over 1000 years under climate field forcing. The results indicate that, when compared with the observations, this model can more effectively simulate the surface and vertical distribution characteristics of the ocean temperature, salinity, total carbon dioxide, total alkalinity, and total phosphate levels. The simulated distribution of the total CO2 in the ocean is basically consistent with observations, of which a low-value zone exists on the surface, beneath which is a high-value zone from 10°S to 60°N. However, the simulations above 2000 m are smaller than observations while simulations below 2000 m are larger than observations. In general, the MOM4_L40 model is found to be a reliable tool for the simulation and research of oceanic carbon cycle processes.","PeriodicalId":55257,"journal":{"name":"地球物理学报","volume":"58 1","pages":"1-19"},"PeriodicalIF":1.4,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/CJG2.20151","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"51220317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}