简介:以地星状星云(PN)是由高度演化的AGB星在一个非常短的时标内(-10^4年)形成的。因此现在认为即是不是全部,许多PN的周围将保留AGB星的中性包层遗迹。分子的观测是示踪PN中性包层的重要控针。1991年10月使用美国五大学射电天文台(FCRAO)的14-m和QUARRY接收系统对两个较年青的行星状星云M1-7和M1-16以及一个年老的行星状星云VV47进行了COJ=1-0的谱线成图观测,得到了这些星云CO谱线积分强度的空间分布和谱线发射的速度范围。主要结果如下:(1)M1-7的CO(1-0)发射类似CO(2-1)的接近于球形分布,整个辐射区略向东北-西南方向倾斜,且稍大于CO(2-1)的发射区,约为44″×44″。,而膨胀速度则小于CO(2-1)的结果,约为20km/s。(2)M1-16是我们观测样本中光学星云最小的一个年青PN(-3″.6)。没有找到对应CO(2-1)成图资料。我们的观测表明,CO(1-0)的分子射区呈椭圆形壳层结构。△α×△δ-82″×45″。可见尽管源的星云半径很小,但分子发射区有很大的促展。该源的CO(1-0)包层的膨胀速度类似M1-7也小于CO(2-1)的,大约是20km/s。边一现象味着COJ=1-0跃迁相对2-1跃迁而言分布在离电离星云较远的部分。(3)VV47是一个年老的行星状星云。最近Bachiller等人用CO(2-1)跃迁对该源进行观测,在-45,-60和-68km/s等3个速度特征上得到了VV47的两个团块型分子凝聚区,它们播散在东南和西北两个区域。我们用QUARRY系统对VV47周围12′.6×15′.0区域进行了长积分时间的CO(1-0)成图测量,共得到了4个谱特征;在VV47的西北区域有-60和-70km/s两个特征,在东南区域有-45和-34.5km/s两个特征。这最后一个特征暗在CO(2-1)观测中没有发现的。由不同特征速度附近CO(1-0)的谱线积分强度空间分布图可见,对于�
简介:AnearthquakewithM7.1occurredinYushu,QinghaiProvince,China,at07:49a.m.onApril14,2010,accordingtotheChineseSeismicStationNetwork.Thesequenceisafore-mainafter-shocktypesequence.AforeshockwithM4.7occurred2hoursand11minutesbeforethemainshock.Therewere12foreshocksand2385aftershocksuntilJune31,2010.Inwhich,thereare21aftershocksbetweenM3.0andM3.
简介:InordertoexploretheabnormalvariationsbeforeandaftertheWen'anM5.1earthquakeonJuly4,2006,thegravitydataobservedbytheWenbaGravityObservationNetworkbeforeandaftertheearthquakewasanalyzed.Therelationshipsbetweengravitychangeandverticaldisplacementandshallowgroundwaterlevelwerediscussed,andelevationcorrectionofthegravitywaspreliminarilyperformed.TheresultsshowthattherewereabnormalgravitychangesbeforetheM5.1earthquake,whichappearedasgravityrisinginthewholeobservationnetwork,especiallyinthesouthpart.AhighgradientofgravityvariationappearedaroundtheepicenterbeforetheM5.1earthquake,especiallyduringtheshortperiodbetweenOctober2005toApril2006.TheboundaryofthepositiveandnegativegravityvariationsgraduallydeflectedandbegantorecoverfromOctober2007.
简介:Basedondatacollectedfromatemporalseismicnetwork,andinadditiontothedatafromsomenearbypermanentstations,weinvestigatethevelocitystructureandseismicityintheRongchanggasfield,wheresignificantinjection-inducedseismicityhasbeenidentified.First,weusereceiverfunctionsfromdistantearthquakestoinvertdetailed1-Dvelocitystructuresbeneathtypicalstations.Then,weusethedouble-differencehypocenterlocationmethodtore-locateearthquakesofthe2010ML5.1earthquakesequencethatoccurredintheregion.There-locatedhypocentersshowthatthe2010ML5.1earthquakesequencewasdistributedinasmallareasurroundingmajorinjectionwellsandclusteredmostlyalongpre-existingfaults.Majorearthquakesshowafocaldepthlessthan5kmwithadominantdepthof~2km,adepthofmajorreservoirsandinjectionwells.Wethusconcludethatthe2010ML5.1earthquakesequencemighthavebeeninducedbythedeepwellinjectionofunwantedwateratadepth~3kmintheRongchanggasfield.
简介:摘要:桐梓县吉源煤矿位于黔北岩溶发育地区,主要开拓系统均布置在煤系地层底板茅口灰岩中,从井下揭露的大量岩溶出水点的涌出特征分析,茅口灰岩多以管道流形式出现,茅口灰岩地下水类型属潜水型而不是承压水类型。而C1煤层上覆长兴灰岩含水层,富水性中等。但是由于C1煤层距上部距长兴灰岩真厚约为75m,根据开采导水裂隙带计算,C1煤层开采后未波及顶板长兴灰岩。故吉源煤矿开采+620m标高以上的C1煤层无顶、底板岩溶突水威胁。
简介:中铁二十四局集团江苏工程有限公司 江苏南京摘要:跨电气化铁路拖拉施工的桥梁,为确保铁路运营安全,铁路局一般要求封锁要点施工。受封锁点时间的限制,临时支墩间距一般不会超过 20m。受既有铁路与桥梁夹角影响,一般拖拉采用纵向拖拉法。本桥梁首次采用横向拖拉法施工,拖拉长度 25.3m。本文对该桥施工技术进行了总结,为今后类似工程提供借鉴。
简介:TheJamesM.HarrisonAwardforOutstandingAchievementwasestablishedbytheIUGSExecutiveCommitteein2004tohonorindividualswhohaveservedtheUnioninanextraordinaryfashionforalongperiodoftime,andwhohavenorecognizedpositionasanofficeroftheUnion.TheawardisnamedforthelateJamesM.Harrison,aninternationallyknownanduniversallyrespectedCanadiangeologist(GeologicalSurveyofCanada)whowasoneofthefoundingfathersoftheIUGSanditsfirstPresident(1961-1964).
简介:正Thethesisofthepaper,whichistheobjectofthisDiscussion,isthattheconsiderabledamagesufferedbytheBasilica,aftertheearthquakeofL'Aquilain2009,wastheexclusiveresultoftheinterventionofseismicimprovementofthenaves,madein2000;such
简介:Completerecordsofmorethan3,000earthquakeeventsintheShanxi,WenzhoureservoirearthquakesequencewererecordedfromAugusttoNovember,2014bythehigh-density,high-resolutionmonitoringstationsoftheZhejiangRegionalDigitalSeismicNetworkandthereservoirearthquakemonitoringnetwork,withamaximummagnitudeofM4.2.Basedon3-Depicenterlocation,focalmechanismsolutions,andincombinationwiththegeologicalandtectoniccharacteristicsofthereservoirarea,theearthquakesequenceisdiscussedinthispaper.ThelinearfittingoftheHypoSATlocationresultsshowthatthemainshockoccurredintheNWtrendingfaultandtheearthquakesequenceisconcentratedinbandsalongtheactivefaults,withastrikeof305°,dippingSWwithdipangleof85°.ByusingP-wavefirstmotionsymbols,weobtainedtheaveragefocalmechanismofM≥3.5earthquakes,withastrike308°anddip84°fornodalplaneII.Thefieldgeologicalsurveyandresearchshowthatthestrike,dipandrakeofnodalplaneIIareroughlyconsistentwiththeoccurrenceoftheShuangxi-Jiaoxifault.ThecomprehensiveanalysisrevealsthattheNW-trendingShuangxi-Jiaoxifaultistheseismogenicstructureoftheearthquakes.
简介:ProcessofsourcedynamicsoftheJingtaiearthquake(M=6.2)Xue-BinDU(杜学彬);Zhi-DeYAN(闫志德)andMing-WuZOU(邹明武)(EarthquakeResearchInstitu...