The researchers studied the Banggai Basin to understand how different types of rocks were formed over time. They looked at the layers of carbonate (like limestone) and siliciclastic (like sandstone) rocks in the area. By analyzing well logs and seismic data, they found four cycles of rock formation. They saw that during low sea levels, sandstone was deposited near the shore, while during high sea levels, limestone formed further out. By studying the fossils in the rocks, they could tell when sea levels rose and fell. This helps us understand how the rocks in the Banggai Basin were created.