| Oil and gas resources is the social industrial food, is the lifeblood of the national economy. With the rapid development of China’s economy, the demand for oil is growing. Petroleum exploration is a very complicated work, in all kinds of geophysical prospecting for oil method, seismic prospecting is one of the most effective methods. Because our country geological structure characteristics, the most shallow oil and gas fields have been developed in the eastern part of the oil and gas fields have entered the deep cut fine looking for stage. With the development of oil and gas exploration, our land, and deep system rich oil and gas resources have been developed, and has become the focus of the present petroleum exploration, but also the future of oil and gas resources to replace the main areas. High resolution seismic technology is in the structure complicated area earthquake sift sure small amplitude structure, small fault and surface structure effective means. This to our country at present the oil and gas exploration has important significance, as our country’s geological structure characteristics, seismic high resolution processing oil field has become one of the aims of exploration and development. Therefore, high resolution exploration put on the agenda.This paper introduces the research background of the deconvolution and the basic theory of deconvolution method. High resolution seismic exploration, mainly on isolated underground bottom reflection coefficient from seismic records section. In seismic reflection wave exploration, a sharp pulse produced by the explosives, in stratum medium dissemination, and returned to earth by the reflection interface. However, due to the filtering effects of stratum medium, spike made by the source is filtered by earth, become a seismic wavelet which has a certain time. Seismic record is the result of a lot of reflected wave superposition. In ordinary seismic record, each reflection wave in the interface is a continuation of time waveform for tens of milliseconds, due to the underground reflection interface is usually the dense layer away from a few meters to dozens of meters, their arrived time difference is for only a few milliseconds, as a result, they interfere with each other on reflection seismic records, it is difficult to distinguish. In order to improve the resolving ability of reflection seismic record, in the hope that the resulting seismic records, each of the interface reflection wave characterized by a narrow pulse, each of the strength of the pulse is proportional to the reflection coefficient of the interface, and the polarity of the pulse reflection interface reflection coefficient of the symbols. The aim of deconvolution is to put seismic wavelet which continues tens of milliseconds compress to a reflection of the narrow pulse reflection coefficient, at the same time suppress ringing and multiple wave, so as to improve the vertical resolution of seismic record. Deconvolution is usually used in pre-stack data, also widely used in the post-stack data. This paper introduces several different deconvolution methods. The most commonly used deconvolution methods mainly are least square deconvolution, predictive deconvolution and two-step statistical wavelet deconvolution. With the continuous development of exploration technology, new deconvolution method is also in constant appear, such as surface consistent deconvolution, homomorphic deconvolution and time-varying spectral whitening, etc.This article introduces the VSP technology related knowledge. VSP mean vertical seismic profile in Chinese, is a method of seismic observation. It should as opposed to a ground-based observations of seismic section. VSP method is some point excitation seismic wave near the surface, along the hole arrangement of different depth some of the multistage multi-component detection point of observation. In VSP, because detector through well placed in the inside formation, so can not only receives the waves spread upward from bottom to top and upgoing converted waves, can also receive the top-down downward propagation downward p-wave and converted wave, and can even receive the shear wave. This is VSP and surface seismic profile compared to one of the most important characteristics.VSP observation method mainly with zero well spaced (zero), non-zero well spaced (non-zero partial), etc. Zero well spaced VSP’s main functions are:to calculate accurately formation average velocity and interval velocity, velocity data, VSP data for scale, comprehensive logging, drilling, logging and seismic data, ground on seismic section in this well, accurate calibration geological horizon, the drilling strata of each seismic reflection prediction and identification of multiple wave. Nonzero well spaced VSP main functions are:to implement the well structure details, use of p-wave and converted wave VSP imaging profile-CDP comprehensive research, analysis, research of reservoir well fracture development situation VSP data and seismic attributes analysis, through the analysis research, play a supporting role for artillery data processing and interpretation.The technology compared with surface observation section have many advantages in terms of basic premise. First, the surface profile is through observation wave field distribution on the surface to study the vertical change of geological section and vertical seismic profile is by observing the wave field in the vertical direction to study the distribution of vertical variation of geological section. So wave kinematics and dynamics characteristics of the more obvious, more direct, more sensitive. Second, the observation point on the surface profile left our internal meaningful to detect medium interface often far away, and the vertical section near or on observation point on the interface. So can directly record ChanChunBo relating to the interface type. Third, surface profile of the main interference wave on seismic records are mostly from the upper section, it is also hard to avoid the upper section, and straight section in the interior of the earth observation "quiet", thus can avoid and decrease the upper section of the interference, easy to identify the wave properties. Fourth, meaningful profiles can be observed on the surface of the wave transmission direction is from inside the medium point to surface, which are upward wave VSP observation points within the medium. It can be observed from bottom to top of upgoing wave, downgoing wave can also be observed from top to bottom. Thus it can be more effective use of the characteristics of wave arrival direction., of course, there are some other characteristics, for example, to facilitate observation of wave particle trajectory, etc.Finally, this paper carries out a deconvolution experiment on a practical VSP seismic data which from the east coasts of China, from the point of view, the effect of treatment improves the resolution of seismic data. |
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