【作者】 刘洋；

【导师】 刘财；

【作者基本信息】 吉林大学 ， 固体地球物理学， 2006， 博士

【摘要】 本文针对中国东北地区地壳范围内的精细结构进行研究。通过对各种地球物理资料的选取和对比,建立了研究区内速度及品质因素等物性参数的关系,具体计算了研究区大范围物性参数分布,并经过对分布的分析研究,得到一组与松辽盆地深层油气、东北地区主要大地构造特征有关的新认识。这些认识属于东北亚区域大地构造理论的一部分,并有一定的应用价值。本文共分十个部分:绪论部分详细的论述了研究区内大地构造的基础和研究意义以及射线方法的发展;第一章着重介绍拟开展工作的地震学基础理论和研究区研究概况;第二章应用一种大地构造模型下的射线追踪方法,对原理进行了论述,并且给出了相应的模型分析;第三章通过对松辽盆地内部六条地震测线数据进行整理和转换,给出了该区域内的纵波速度分布特征;第四章利用满洲里-绥芬河地学断面域天然地震横波速度及广角纵波速度的分布特征,给出该断面域内的纵、横波速度比关系;第五章提出一种速度外推关系,并以此对整个中国东北地区地壳范围内的纵波速度进行求取;第六章应用转换纵波数据建立新的莫霍深度分布关系,并利用本此研究所选取的射线追踪方法对莫霍面过渡带的结构进行了研究;第七章利用重新建立的壳幔介质品质因素与纵波速度间的关系,对整个研究区内的Q值分布规律进行了分析;第八章利用各种物性参数给出整个东北地区的构造地质-地球物理新认识;本此研究的最后结论部分对全文工作进行了简要的总结。更多还原

【Abstract】 In the theory study of solid geophysics science, the large scale cracking andmineralizing that are caused by the deep dynamic process of crust and theinteraction between crust, manthle, aureole and strata are still leading edgescientific problems, and the problems are not yet solved. The exchange of deepmatter and energy with deep dynamic process is the core of mineralizingmechanism and deep physics – chemistry process in northeast of China. The papercalculates the physical property distribution of region of interest, and gets a lot ofnew cognition about Songliao basin deep oil gas and geotectonics characteristics ofthe northeast of China through analyzing the distribution. The cognition belongs topart of geotectonics theory about northeast Asia, and there is a certain applied cost. Aiming at the crust of in northeast of China, the paper collects and arrangesthe all sorts of geophysics data incluing nature earthquake, near normal reflection,artificial wide-angle earthquake and gravitation. This thesis mainly studies thedistribution of P wave in Songliao basin, and the paper newly discusses thedivision of tectonic element. the paper analyzes the distributional characteristics ofvelocity about the northeast of China, and then get the distributional curves of Pwave velocity within crust range in region of interest through a new P and S wavevelocity relationship. On the basis of the P wave distribution, the paper obtains thenew characteristics about Moho depth and Q value within crust range in entirenortheast region of China. By using ray tracing technology under geotectonicsmodels, the paper detailedly discusses the interior structure of transition zoneabout Moho. According to this study, the paper brings forward the new cognitionabout fine structure of crust in entire northeast region of Chia. All cognitionsprovide the new references for the geotectonics theory.The model structures of geotectonics models are usually easy, so the classicalray tracing methods can always trace the precise forward results, but the range ofgeotectonics model is very large, the forward data size is so big that the classicalray tracing under seismic prospecting model need plenty of time to calculate, theresult usually can be gotten. Aiming at geotectonics models, the paper applies anew ray tracing method that fits for 2D geotectonics models. Through calculatingtheory model, the method can accurately and quickly get the trace of seismic ray.Then the paper analyzes the recognition question about thin bed under basin modeland geotectonics model by using the new ray tracing method. Under basin medel,the thickness of thin bed h is the relationship about theory wavelet frequency f andthin bed velocity v: . And that under geotectonics medel, therecognition of thin bed is more complex, the thickness is affected by executionconditions, collection method and processing procedures besides seismic waveletand velocity.h ≥0.35v/fThe thesis study the velocity structure in Songliao basin, through arrangingthree near normal reflection profiles data and three long artificial seismic profilesdata, the paper sketches the the distrition relation of P wave velocity withinSongliao basin range. After qualitatively and quantificationally analyzing the Pwave velocity under different depth, the divitions of geological structure are mostcorresponding to the changement of P wave velocity. According to the results, wepresent the new geological structure cognition, which provede the reliable7reference for the direction of hydrocarbon prospecting.In the MANZHOULI-SUIFENHE geoscience transect, the paper analyzes thevelocity distribution characteristics about the P wave velocity of artificialwide-angle earthquake and S wave velocity of nature earthquake. By generalizingtwo data, the paper gets the velocity ratio of P wave and S wave in the geosciencetransect. The ratio provides the basic information for calculating P wave velocitywithin the entire northeast region of China. Based on the trend of geologicalstructure in northeast of China, the paper puts forward an extrapolationrelationship of velocity. By using the velocity ratio of P wave and S wave in theMANZHOULI-SUIFENHE geoscience transect and S wave velocity in the regionof interest, the paper finally obtains the P wave velocity distribution in northeast ofChina.The paper chooses the contour line whose value is 8.05km/s of P wavevelocity in northeast of China to be the botton of Moho, and describe the newdepth distribution in detail. By comparing with the Moho of nature earthquake Swave velocity and of gravity field, the new data can more detailedly depict theshape of Moho. the paper also studies the interior structure of Moho transitionzone through the ray tracing method under geotectonics model. The results showthat there are structures in the Moho transition zone, the number of earthquakephases are relative to the strata of transition zone and the inhomogeneity of Mohothickness. In essence Moho is a fluctuant transition zone with big wave impedancedifference and kinds of lithologies.In the study of strata absorption and attenuation, quality factor Q is the one ofmain parameters that can weigh the absorption and attenuation. There are too manyfactors to affect Q value, so it is very difficult to establish the relationship betweenQ values and all fators, field actual measurement is a rational method. The thesisestablishes the new relationship of crust and mantle media between Q value and Pwave velocity on the base of the relationship between the two values under basinmode. According to the distribution characteristics of P wave velocity in region ofinterest, the paper gets the distribution relation of Q value that represents theregulation of absorption and attenuation in northeast of China.The study analyzes the geology-geophysics characteristics in whole northeastof China by the numbers, we bring forward the oil gas prospect area according tothe six profiles in Songliao basin. Through the relationship of thirty-six P wavevelocities and Q value, we analyze the distribution characteristics of middle andupper crust. We study the area of the granite band of the Great Xingan Mountainsin northeast of China, and then discuss the attenuation mechanism of lithosphereand crust.The paper describes the physical property parameters about crust in northeastof China by establishing the relationship of physical property parameters, somenew acknowledge are obtained. It is very significative of the results to the theoryof deep oil gas potentiality and the establishment of resources assessment system.The information provide some science reference for the source regionalizationabout sustainable development of oil gas resources and strategy system of nationaloil gas resource in northeast of China.更多还原