Structure Identification Method Based On Seismic Phase Composite Attributes

At present,those mature seismic data interpretation techniques are often derived from the amplitude attribute,but there are few studies based on the phase attribute.However,the phase attribute has the outstanding advantage for not being affected by the intensity of reflection and has a good application prospect in the fine interpretation of earthquake.Therefore,this paper puts forward a series of interpretation methods around the phase attribute and makes combination or complementation with some existing technologies.Specific to study the following:First of all,based on the conventional instantaneous phase attribute method,we propose a local phase change attribute combining sliding window.By opening the local sliding window on the whole trace,the real phase variation in the local time window can be obtained to avoid the influence of the accumulate phase effect,In this way,we can obtain the method of structure identification and interface determination based on phase attribute,which increases the accuracy and credibility of seismic interpretation.Secondly,we improve the phase attribute based on the existing complex coherence technology.In this paper,the phase attribute obtained from the complex correlation coefficient is used as the basis for the new structure identification,and the relationship between phase and structural anomaly is creatively established by using the idea of "phase shift",so as to give full play to the advantages of phase attribute in identifying the region of structural anomaly,and realize the complementary advantages with the traditional complex coherence in the interpretation work.Again,we introduce frequency division technology and try to obtain frequency division phase attributes by using Gabor transformation and sparse inversion spectrum decomposition.The aim of this method is to establish the corresponding relation between frequency and structure scale through the results of different frequency components,which can help us to achieve a more detailed interpretation result.Finally,in order to test the effect of the structure identification method based on different phase attributes proposed in this paper,we use a number of representative real data to verify the applicable conditions,advantages and limitations of each method,and establish a relatively complete structure identification system based on phase composite attributes.During this process,we compare the results with the data,and then evaluate and improve the method from multiple perspectives.