Theconvolutionaldiferentiatormethodfornu┐mericalmodelingofacousticandelasticwave┐fields

Ｔｈｅｃｏｎｖｏｌｕｔｉｏｎａｌｄｉｆｅｒｅｎｔｉａｔｏｒｍｅｔｈｏｄｆｏｒｎｕ┐ｍｅｒｉｃａｌｍｏｄｅｌｉｎｇｏｆａｃｏｕｓｔｉｃａｎｄｅｌａｓｔｉｃｗａｖｅ┐ｆｉｅｌｄｓＺＨＯＮＧ－ＪＩＥＺＨＡＮＧ（张中杰），ＪＩ－ＷＥＮＴＥＮＧ（滕吉文）ａｎ...     

Geneticprogrammingforpredictionofearth┐quakesequencetype

Ｇｅｎｅｔｉｃｐｒｏｇｒａｍｍｉｎｇｆｏｒｐｒｅｄｉｃｔｉｏｎｏｆｅａｒｔｈ┐ｑｕａｋｅｓｅｑｕｅｎｃｅｔｙｐｅＹＵ－ＤＯＮＧＣＡＩ（蔡煜东）ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＭｅｔａｌｕｒｇｙ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＳｃｉｅｎｃｅｓ...     

Studyonthesourcesofsomedeepfocusearth┐quakesinNorthwestPacificregion

Ｓｔｕｄｙｏｎｔｈｅｓｏｕｒｃｅｓｏｆｓｏｍｅｄｅｅｐｆｏｃｕｓｅａｒｔｈ┐ｑｕａｋｅｓｉｎＮｏｒｔｈｗｅｓｔＰａｃｉｆｉｃｒｅｇｉｏｎＡＮ－ＹＩＬＩ（李安奕）ａｎｄＳＨＡＯ－ＸＩＡＮＺＡＮＧ（臧绍先）ＧｅｏｐｈｙｓｉｃｓＤｅｐａｒｔｍｅｎｔ，Ｐｅ...     

Researchonpredictionofthefolowingnotice┐ableshocksofearthquakesequences

Ｒｅｓｅａｒｃｈｏｎｐｒｅｄｉｃｔｉｏｎｏｆｔｈｅｆｏｌｏｗｉｎｇｎｏｔｉｃｅ┐ａｂｌｅｓｈｏｃｋｓｏｆｅａｒｔｈｑｕａｋｅｓｅｑｕｅｎｃｅｓＰＵ－ＸＩＯＮＧＬＩＵ（刘蒲雄），ＸＩＵ－ＱＩＣＨＥＮ（陈修启），ＸＩＡＯ－ＪＩＡＮＬＵ（吕晓健）ａｎｄＤ...     

StudyofCurieisothermalsurfaceinSichuanBasinandtheseismicareaonitswesternmar┐gin

ＳｔｕｄｙｏｆＣｕｒｉｅｉｓｏｔｈｅｒｍａｌｓｕｒｆａｃｅｉｎＳｉｃｈｕａｎＢａｓｉｎａｎｄｔｈｅｓｅｉｓｍｉｃａｒｅａｏｎｉｔｓｗｅｓｔｅｒｎｍａｒ┐ｇｉｎＸＩＡＮＺＨＡＮＧ（张先），ＸＩ－ＦＥＮＧＨＵ（虎喜凤），ＪＩＮＧ－ＸＩＵＳＨＥＮ（沈京秀...     

IsatypeoflowfrequencyULFmagneticdistur┐banceakindofearthquakeprecursors

ＩｓａｔｙｐｅｏｆｌｏｗｆｒｅｑｕｅｎｃｙＵＬＦｍａｇｎｅｔｉｃｄｉｓｔｕｒ┐ｂａｎｃｅａｋｉｎｄｏｆｅａｒｔｈｑｕａｋｅｐｒｅｃｕｒｓｏｒｓ？ＸＩＮＧ－ＣＡＩＬＩ（李兴才），ＨＵＩ－ＸＩＮＣＡＯ（曹惠馨），ＫＥ－ＸＩＮＲＥＮ（任克新）ａｎｄＣＨＵ...     

QβstructureofthecrustanduppermantleintheeasternSino┐Koreanparaplatform

ＱβｓｔｒｕｃｔｕｒｅｏｆｔｈｅｃｒｕｓｔａｎｄｕｐｐｅｒｍａｎｔｌｅｉｎｔｈｅｅａｓｔｅｒｎＳｉｎｏ┐ＫｏｒｅａｎｐａｒａｐｌａｔｆｏｒｍＺＨＥＮＧ－ＱＩＮＨＥ（何正勤），ＴＡＩ－ＬＡＮＹＥ（叶太兰）ａｎｄＷＥＩ－ＧＵＯＳＵＮ（孙为国）Ｉｎｓｔｉ...     

Strongearthquakeactivityalovertheworldandstrong┐moderateearthquakeactivitywithinandnearChina（June～Au

Ｓｔｒｏｎｇｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙａｌｏｖｅｒｔｈｅｗｏｒｌｄａｎｄｓｔｒｏｎｇ┐ｍｏｄｅｒａｔｅｅａｒｔｈｑｕａｋｅａｃｔｉｖｉｔｙｗｉｔｈｉｎａｎｄｎｅａｒＣｈｉｎａ（Ｊｕｎｅ～Ａｕｇｕｓｔ，１９９５）ＰＥＩ－ＳＨＡＮＣＨＥＮ（陈培...     

Onthephysicalmodelofearthquakeprecursorfieldsandthemechanismofprecursors′time┐spacedistribution（Ⅱ）Ho

Ｏｎｔｈｅｐｈｙｓｉｃａｌｍｏｄｅｌｏｆｅａｒｔｈｑｕａｋｅｐｒｅｃｕｒｓｏｒｆｉｅｌｄｓａｎｄｔｈｅｍｅｃｈａｎｉｓｍｏｆｐｒｅｃｕｒｓｏｒｓ′ｔｉｍｅ┐ｓｐａｃｅｄｉｓｔｒｉｂｕｔｉｏｎ（Ⅱ）Ｈｏｗｄｏｔｈｅｓｔｒｅｓａｎｄｓｔｒａｉｎｆｉｅｌｄ...     

AIC analysis of categorizing data for earthquakes and velocity structures in North China

ＩｎｔｒｏｄｕｃｔｉｏｎＥａｒｔｈｑｕａｋｅｉｓａｎｏｕｔｃｏｍｅｏｆｔｅｃｔｏｎｉｃａｃｔｉｖｉｔｙ．Ｉｔｉｓｏｎｅｏｆｔｈｅｍａｉｎｓｔｕｄｙｔａｒｇｅｔｓｏｆｓｅｉｓｍｏｌｏｇｉｓｔｓｔｏｕｎｄｅｒｓｔａｎｄｔｈｅｄｅｅｐｇｅｏｌｏｇｉｃｓｅ...     

Therelationshipbetweenearthquakesandposi┐tionsoftheSunandMoon（Ⅰ）——Sometemporalcharacteristicsofgene

Ｔｈｅｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｅａｒｔｈｑｕａｋｅｓａｎｄｐｏｓｉ┐ｔｉｏｎｓｏｆｔｈｅＳｕｎａｎｄＭｏｏｎ（Ⅰ）——Ｓｏｍｅｔｅｍｐｏｒａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｇｅｎｅｒａｌｉｚｅｄｐｒｅｓｈｏｃｋｓｅｑｕｅｎｃｅｉｎ...     

Resistivity tomography study on samples with water-bearing structure

IntroductionThestudyonthevariationoftheeIectricaIpropertiesofsimulatingsamplesatcertainphysi-calconditionsinthelaboratoryisanimportantmethodtounderstandthecomposition,movementandevolutionofthematerialsintheseismicsourceregionduringseismogenicprocessandisaIsoanimPortantsupplementtothefieldexperimentofeathquakemonitoringbymeansofelectricaImethod.ThepreviouslymadesimuIationexperimentsindicatethatthevalueofapparentresistivityofwatCrsaturatedintactrocksamplesmaydecreaseoneorderofmagnitudebeforefr…     

Inversion of 3-D crustal P-wave velocity structure in Ningxia and its neighborhood by using direct, reflected and refracted waves

IntroductionUsingarrival-timeofobservedearthquakewavestoinfertheinteriorvelocitystrUctUreoftheearthisthebaseworkofgeophysics.Thepreviousstudyappliedclassicalmethodshaveobtainedmanymeaningfulresults(Jeffreys,Bullen,1940;Haddon,Bullen,1969;Mizutani,Abe,1972),andtodaytheseresultsstillisthefoundationbywhichweunderstandtheeaFth.Inthelasttwentyyears,alongwiththedevelopmentofseismicobservationarray,inversiontheoryandthepowerfulcomputer,theinversionmethodsanddatausingtoexplorethestructureofEarth'S…     

Rèsumèonnewmonograph“AdvanceinMathematicalSeismology”edit┐edbyJunjiKoyama＆FengDeyi

Ｒèｓｕｍèｏｎｎｅｗｍｏｎｏｇｒａｐｈ“ＡｄｖａｎｃｅｉｎＭａｔｈｅｍａｔｉｃａｌＳｅｉｓｍｏｌｏｇｙ”ｅｄｉｔ┐ｅｄｂｙＪｕｎｊｉＫｏｙａｍａ＆ＦｅｎｇＤｅｙｉＴｈｅｎｅｗｍｏｎｏｇｒａｐｈ“ＡｄｖａｎｃｅｉｎＭａｔｈｅｍａｔｉｃａｌＳｅｉｓｍｏ...     

Crustal structure of the eastern Dabie orogenic belt from the seismic tomography and wide-angle reflection studies

IntroductionDuringtheMarchof1997,anactive-sourceseismicexperimentwasundertakenbyajointSino-GermanseismicprojecttoinvestigatethesubsurfacestructurebeneaththeDabieUHPMbeltwithintheframeworkofinternationalContinentalScientificDrillingProgramme(ICDP).ThetargetareaislocatedbetweenYuexiandQianshaninAnhuiProvince,andgeologicallyonthejunctureoftheDabieorogenicbeltandtheTanlufault(Figurel).Thisexperimentisparticularlydesignedsinthefieldcombinedwiththeinterestsofseismictomographyandwide-anglere…     

The spatial characteristic of the short－term and imminent anomalies of waterradonbe┐foreearthquakeinthemainlandofChina

Ｔｈｅｓｐａｔｉａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｏｆｔｈｅｓｈｏｒｔ┐ｔｅｒｍａｎｄｉｍｍｉｎｅｎｔａｎｏｍａｌｉｅｓｏｆｗａｔｅｒｒａｄｏｎｂｅ┐ｆｏｒｅｅａｒｔｈｑｕａｋｅｉｎｔｈｅｍａｉｎｌａｎｄｏｆＣｈｉｎａＸＵＥ－ＢＩＮＤＵ（杜学彬），Ｘ...     

Crustal and upper mantle structure and the deep seismogenic environment in the source regions of the Lushan earthquake and the Wenchuan earthquake

Following the M w 7.9 Wenchuan earthquake, the M w 6.6 Lushan earthquake is another devastating earthquake that struck the Longmenshan Fault Zone (LFZ) and caused severe damages. In this study, we collected continuous broadband ambient noise seismic data and earthquake event data from Chinese provincial digital seismic network, and then utilized ambient noise tomography method and receiver function method to obtain high resolution shear wave velocity structure, crustal thickness, and Poisson ratio in the earthquake source region and its surroundings. Based on the tomography images and the receiver function results, we further analyzed the deep seismogenic environment of the LFZ and its neighborhood. We reveal three main findings: (1) There is big contrast of the shear wave velocities across the LFZ. (2) Both the Lushan earthquake and the Wenchuan earthquake occurred in the regions where crustal shear wave velocity and crustal thickness change dramatically. The rupture faults and the aftershock zones are also concentrated in the areas where the lateral gradients of crustal seismic wave speed and crustal thickness change significantly, and the focal depths of the earthquakes are concentrated in the transitional depths where shear wave velocities change dramatically from laterally uniform to laterally non-uniform. (3) The Wenchuan earthquake and its aftershocks occurred in low Poisson ratio region, while the Lushan earthquake sequences are located in high Poisson ratio zone. We proposed that the effect of the dramatic lateral variation of shear wave velocity, and the gravity potential energy differences caused by the big contrast in the topography and the crustal thickness across the LFZ may constitute the seismogenic environment for the strong earthquakes in the LFZ, and the Poisson ratio difference between the rocks in the south and north segments of the Longmenshan Fault zone may explain the 5 years delay of the occurrence of the Lushan earthquake than the Wenchuan earthquake.     

Quasi-waveform seismic tomography of crustal structures in the capital circle region of China

Seismic tomography is one of the main tools to explore the interior of the earth.In this study,the quasi-waveform seismic tomographic method is used for the first time to reveal the crustal structures in the capital region of China.3-D highresolution V_P,V_S and the Poisson’s ratio models are generated by inverting 29839 direct P-and 29972 direct S-wave traveltimes selected from 3231 local earthquakes.The results reveal strong crustal heterogeneities.The velocity anomalies at shallow depths are well consistent with surface geologic structures.The relatively low-velocity anomaly layer in the middle crust may be the result of multiple phases of tectonic activity.Earthquakes generally occurred on the boundaries of high-and low-velocity and Poisson’s ratio anomalies.There are obvious low-velocity anomalies below the hypocenters of the Tangshan earthquake and the historical Sanhe-Pinggu earthquake,implying the existence of fluids.The similar velocity structures around the hypocenters of the two earthquakes indicate that the occurrences of the two earthquakes may be related to the same mechanism.The highresolution velocity models provide important observational constraints on the small-scale heterogeneities and dynamic mechanism of the crust in the capital region of China.     

Advanced characterization of pores and fractures in coals by nuclear magnetic resonance and X-ray computed tomography

This paper demonstrates capabilities of low-field nuclear magnetic resonance (NMR) and microfocus X-ray computed tomography (μCT) in advanced, nondestructive, and quantitative characterization of pore types, producible porosity, pore structure, and spatial disposition of pore-fractures in coals. Results show that the NMR transverse relaxation time (T2) at 0.5–2.5, 20–50, and >100 ms correspond to pores of <0.1 μm, >0.1 μm, and fractures, respectively. A much higher T2 spectrum peak reflects a much better de...     

多震相走时和波形三维地震成像方法及在朝鲜半岛和祁连山地壳结构研究的应用

本项成果包括：提出天然地震走时反演层析成像技术,采用下列方法使得处理结果得以改善：1)利用Pg,Sg,Pm,Sm,Pn,Sn等震相增大约束条件;2)用已有精度较高的人工地震测深结果作速度约束;3)用波形反演来修改模型,把波源,介质吸收,散射等全部物理特征集中反映在记录中,把诸多物理量开发出来互为约束,以修改后的模型再作反演,使解的稳定性大大提高;4)采用最优化过程,选择遗传算法。可以进行震源定位,走时反演,波形反演;5)得到任意深度的速度分布及从地表到Moho面的速度剖面。主要应用结果：对于朝鲜半岛南部,划分为5(沿纬度)*６(沿经度)*8(沿深度)块,对于中部分288块.得到从地表到M面的8个水平切面;中部地区沿纬度13个二维剖面及其Moho面深度分布。上述方法也用于祁连山中东段地壳三维结构成像加上地震台网数字记录,反演。该区属塔里木-阿拉善地块走廊过渡带与北祁连褶皱带;从剖面可看出该地块上地壳低速层厚,下地壳有-低速层。北祁连褶皱带盆地与隆起构造之间的起伏差异,显示古浪断裂与金强河断裂之间的深部差异与界线。两地区的结果表明,这些剖面对认识大地构造、地质结构的稳定性,深部事件的性质是很有益的,对地球动力学研究也有重要意义。