裂缝型储层检测方法——P波方位各向异性技术

Nowadays, the exploration of fractured reservoir plays a vital role in the further development of petroleum industry through out the world. Fractured hydrocarbon reservoirs are widely distributed in China. Usually, S-wave technique prevails, but it also has its disadvantage, prohibitive expense in S-wave data acquisition and processing. So directly utilizing P-wave data to detect fractures, comes to our mind. We briefly introduce theoretical model (HTI) for fractured reservoir. Then study Ruger’s reflectivity method to recognize reflection P-wave reflection coefficient of the top and bottom interface of HTI layer respectively, and its azimuth anisotropy character. Base on that study, we gives a review and comparison of two seismic exploration technologies for fractures available in the industry-- P-wave AVO and AVA. They has shown great potential for application to the oil and gas prediction of fractured reservoir and the reservoir fine description．Every technique has its disadvantage, AVO limited to small reflection angle; and AVA just offering relatively results. So that, We can draw a conclusion that a better way to any particular field is using synthesis of multiple data sources including core、outcrop、well-test、image logs、3D VSPs, generally to improve the accuracy.

岩石热开裂的实验研究

Micro-cracks appeared between the boundaries of different minerals of rocks during heating process, because of different thermal expansion coefficients of minerals, this phenomenon is referred as thermal cracking of rocks. The transport property of rocks was changed greatly due to the thermal cracking induced micro-cracks network, for example, the permeability of carbonate increases about 10 times when the temperature arise from room temperature to 110～120℃. Thermal cracking of rocks is a new research field of rock physics, which related closely to rock mechanics, mineralogy as well as experimental technology. The thermal cracking experiments of various rocks were performed, the rock macroscopic properties such as porosity, permeability, velocities of elastic waves in rocks were obtained as a function of temperature of heating process, and the microscopic structures of rocks were observed by using Scanning Electro-Microscope (SEM). The mechanism and the theoretical model of thermal cracking of rocks are given at present paper. Finally, the potential implication of rock thermal cracking to petroleum industry is discussed.

弱各向异性介质中传播的地震波及其速度重建

We begin our studies to make the best of information of seismic data and carry out the description of cracks parameters by extracting anisotropic information. The researching contents are: (1) velocity and polarization anomaly of seismic wave (qP and qSV wave) in weak anisotropic media; (2) reflection seismic synthetic record in anisotropic media; (3) multiple scattering induced by cracks; (4) anisotropic structure inversion and velocity reconstruction with VSP (Vertical Seismic Profile) data; (5) multi-parameters analysis of anisotropy in time-domain and depth-domain. Then we obtain results as follows: (1) We achieve approximate relation of qP and qSV wave's velocity and polarization property in weak anisotropic media. At the same time, we calculate anisotropic velocity factors and polarization anomaly of several typical sedimentary rocks. The results show there are different anisotropic velocity factors and polarization anomaly in different rocks. It is one of the primary theoretical foundation which is expected to identify lithology; (2) We calculate reflection seismic synthetic record with theoretical model; (3) We simulate scattering induced by cracks with Boundary Element Method. Numerical studies show that in the presence of cracks; spatial and scale-length distributions are important and cannot be ignored in modeling cracked solids; (4) From traveltimes information of VSP data, we study the velocity parameter inversion of seismic wave under isotropic and anisotropic models, and its result indicate that the inversion imaging under anisotropic model will not destroy the original features of isotropic model, but it will bring on some bigger error if we adopt the method of isotropic model for anisotropic model data. Further more, basing on the study we develop the CDP mapping technology of reflecting structure under isotropic and anisotropic models, and we process real data as a trial of the methods; (5) We study the problem of initial model reconstruction of anisotropic parameters structure represented by Anderson parameter in depth domain for surface data.

高斯束偏移的方法及应用

Gaussian beam is the asymptotic solution of wave equation concentred at the central ray. The Gaussian beam ray tracing method has many advantages over ray tracing method. Because of the prevalence of multipath and caustics in complex media, Kirchhoff migration usually can not get satisfactory images, but Gaussian beam migration can get better results.The Runge-Kutta method is used to carry out the raytracing, and the wavefront construction method is used to calculate the multipath wavefield. In this thesis, a new method to determine the starting point and initial direction of a new ray is proposed take advantage of the radius of curvature calculated by dynamic ray tracing method.The propagation characters of Gaussian beam in complex media are investigated. When Gaussian beam is used to calculate the Green function, the wave field near the source was decomposed in Gaussian beam in different direction, then the wave field at a point is the superposition of individual Gaussian beams.Migration aperture is the key factor for Kirchhoff migration. In this thesis, the criterion for the choice of optimum aperture is discussed taking advantage of stationary phase analysis. Two equivalent methods are proposed, but the second is more preferable.Gaussian beam migration based on dip scanning and its procedure are developed. Take advantage of the travel time, amplitude, and takeoff angle calculated by Gaussian beam method, the migration is accomplished.Using the proposed migration method, I carry out the numerical calculation of simple theoretical model, Marmousi model and field data, and compare the results with that of Kirchhoff migration. The comparison shows that the new Gaussian beam migration method can get a better result over Kirchhoff migration, with fewer migration noise and clearer image at complex structures.

大学生应激应付研究

In this study, we made research on coping with stress in undergraduate students. The whole work included two parts: (a) We developed the Coping Strategies Questionnaire and had it tested. Five kinds of coping strategies were found by factor analysis: Problem Solving, Passive Acceptance, Support Seeking, Emotion Regulation, and Unadaptation. The reliability and validity coefficients of the questionnaire was high. (b) We examined the relations among personality characteristics (Locus of control, Extraversion, Neuroticism), emotion state, cognitive appraisal (psychological pressure, controllability, resource of social support), and the specific coping processes in several specific stressful events. The results indicated that coping have some degree of consistency across different situations which suggested that there is a general coping tendency, and that this general coping tendency, in addition to the above considered variables, have different degree of effects on subjects' choice of specific coping strategies. Finally, theoretical model of the relationship was tested through path analysis.