Abstract:

Influenced by buried depth and diagenetic compaction, low porosity and low permeability reservoir developed in Paleogene in Wenchang A sag of the western Pearl River Mouth Basin. The seismic reflection characteristics were characterized by poor continuity and low signal-to-noise ratio, so it is difficult to carry out reservoir prediction and hydrocarbon detection. To solve this fundamental problem that conventional geophysical method is difficult to achieve an effective application due to the general overlay of rock physics parameters, the frequency dividing attribute technique of advantage trace was applied to qualitatively predict low porosity and low permeability reservoir by avoiding geophysical technology depending on logging petrophysical analysis results, which depends on totally seismic data. Meanwhile, based on logging petrophysical analysis results, prestack inversion based on curve reconstruction was used to semiquantitatively predict low porosity and low permeability reservoir. Through test, both the two methods have a certain effect for predicting low porosity and low permeability reservoir, so they are worthy of further promotion.

Key words:  paleogeomorphologyrestoration , gas-water distribution , impression method , Ma 5 ₄ ¹ , Ordovician , Wushen-qi-Zhidan area