Research and application of reserve forecasting techniques of complex ultra-deep low-permeability clastic reservoir

The Carboniferous reservoir in the 3rd block of the Tahe Oil Field is a set of shallow-water andoffshore facies elastic precipitation,characterized by deep burial depth,thin sand body and unstable sanddistribution.The major frequency of seismic data ranged from 35 to 41 Hz,thus the resolution of C1k1WLS about 26-32 m.However,the maximum depth of sand body was 12 m,USUally 2-6 m,making itdifficult to identify sand body with normal seismic data.In order to solve the problems in C1k1 thin sandbody prediction and identification,several methods and techniques were used,such as amplitude chip-ping evolution,high-frequency seismic tomography,seismic data separate frequency processing,impe-dance inversion and reservoir seismic sensible factor high definition inversion.Through effect analysisand comparison,a set of reserve prediction method was proposed.Reservoir sensible factor high-defini-tion inversion was chosen to deal with sandstone and mudstone thin alternating layers.The methodmight be helpful for studies of complex ultra-deep low-permeability elastic reservoirs.