Abstract:

Seismic sedimentology is a new traverse subject which studies the sedimentary microfacies detailedly with 3D seismic data, combining with core and logging, using advanced geophysical technique. B682 borefield in Shengli oilfield mainly develops nearshore-subaqueous-fan facies, semi-deep lake and deep lake facies, and turbidite facies in the middle and lower part of Sha 3 Member, in which the turbidite sandbody is the main petroliferous sand body. For the analysis of turbidite-sand distribution, this research studies the intended interval in B682 borefield under the direction of seismic sedimentology with 90° phase shift and stratal slicing. And it can be found that, vertically, the turbidite sand body is mainly developed in the early period and the late period of the development of the middle and the lower of Sha 3 Member in B682 borefield separately. It is also found that, horizontally, the turbidite sand body in the early period of the lower part of Sha 3 Member mainly developed in the east of the area, the distribution of which can reach 1.71 km².The turbidite sand body in the late period of the lower part of Sha 3 Member mainly develops in the east, the south east and the south, the distribution of which in the south is bigger,reaching 3.37 km²,and the distribution of which in the south east and the south is smaller, about 1.61 km². The turbidite sand body in the early period of the middle part of Sha 3 Member mainly develops in the north-east and the south-east, the distribution of which can reach 1.90 km². The turbidite sand body in the late period of the middle part of Sha 3 Member mainly develops in the south-east and the south-west, the distribution of which is all small about 1.15 km².

Key words: seismic sedimentology, phase shift, stratal slicing, near-shore subaqueous fan, turbidite