The researchers studied how sediment fills up in a specific area in the Pearl River Mouth basin. They looked at different types of data like seismic images and drilling results to understand how the sediment layers formed over time. They found that the area has different zones with varying types of sediment systems, like underwater fans and river deltas. The distribution of faults in the area also affects how sediment is deposited. Overall, the study helps us understand how the landscape in this region has changed over millions of years.