Study On Reef Recognition And Formation Model In Madura Area Based On Seismic Attributes

The formation interface with wave impedance difference underground is the cause of seismic reflection wave.The change of seismic reflection wave characteristics indicates the lateral change of underground formation characteristics,that is,the change of seismic attributes.It can be seen that the information representing the characteristics of underground strata is included in seismic attributes,which is the physical basis for the prediction of oil and gas reservoir parameters and the judgment of formation lithology by using seismic attributes to carry out research.There are E-W grain limestone reefs on the outer shelf platform in the northern part of the Madura Strait Basin.Granular limestone reefs are deposits formed by various sedimentation processes of foraminifera(mainly Globigerinid)shells,which developed in the northern margin of the basin during the early Pliocene compression inversion period.Because of the particularity of reef growth and development,Its Petrological Characteristics and other information are often symbolically reflected,so the reflection characteristics of the reef profile and seismic attributes are quite different from those of surrounding rocks.These differences lay a foundation for people to identify reefs by seismic interpretation and seismic attribute extraction technology.For example,in seismic profiles,reefs are often characterized by symmetrical hilly shape reflection,pre-reef slope accumulation reflection,disordered reflection and discontinuous strong reflection within reefs,etc.The data used in this paper are mainly from two three-dimensional exploration areas,oyong3 D and central3 D,as well as several exploration wells.The Pliocene mundu formation sedimentary strata in the Madura Strait Basin with Globigerinid fossils drilled in O-2 well are taken as the research object.Firstly,starting from the geological background,the importance of potential oil and gas resources and geographical location in the study area is introduced,and the Cenozoic structural characteristics of the basin and the corresponding strata in different periods of development are described.On the basis of summarizing the previous studies on the classification and seismic response of reefs,the reflection characteristics of reefs on seismic profiles are further clarified by establishing forward models.By extracting the seismic attributes of the central oyong3 D area and comparing the drilling information,the best attributes which can effectively identify the reefs in the study area are selected,and this conclusion is applied to the larger central 3D area which has not been fully explained to extract its seismic attributes.Seismic profile interpretation of the suspected reef development area is carried out,and the results are compared with the known seismic response characteristics of the reef.At the same time,the reef sedimentary environment reflected by the deep tectonic map on the top of the mundu Formation is used to verify.Finally,the spatial distribution of the granular limestone reef in the basin is obtained.Finally,combined with the sedimentary and tectonic activities in the history of the basin,the important factors controlling the growth of reefs in the study area are obtained,and the development model of reefs in the platform margin of the mundu Formation in the Madura Strait Basin is summarized.