The north slope of Baiyun Sag is one of the important areas for the oil-gas exploration in Pearl River Mouth Basin. Based on cores

seismic

log and paleontological data

14 third-order sequences were identified in the Neogene of the study area by the former researcher. Under an isochronous stratigraphic framework

this paper analyzed the sequence architecture of key sequences on the north slope of Baiyun sag

and predicted the play fairways. From north to south

4 types of sequences

including H type

TH type

T type and L type

were developed successively. Among them

the H type and L type were favorable for reservoir development

while T type was favorable for development of source rocks. Moreover

the joint control of multiple geologic conditions led to the development of various types of delta in the Neogene on the north slope of Baiyun sag. Alternating shelf-margin delta

inner-shelf delta and mid-shelf delta may occur successively in a single sequence. The L type sequence is mainly composed of shelf-margin delta

canyon channel and turbidite fans;the T and TH type sequences are dominated by inner-mid shelf delta and shelf system;and the H type sequence consists minaly of mid-shelf delta and shelf system. As a result

distributary channel sandbodies in the inner- or mid-shelf delta in the northern part of Baiyun sag

as well as the underwater distributary channel

river mouth bars

distal bars

canyon channel and turbidite fans were all favorable for oil & gas accumulation in the study area.