Magma events in the early stage of basin rifting in the Santos basin played a key role in the development of the carbonate reservoir. Taking the igneous rock- coquinas complex in Block L as a case study, this paper revealed two stages of magma events through systemic analysis, testing of igneous rock mineralogy, petrology, geochronology, petro- geochemistry, and wireline log curves. Compared with Santonian- Campanian thin layers of intrusive bodies, the Aptian extrusive magma dominated this complex and experienced at least 11 episodes of eruptions, including 7 discontinuous eruptions and 3 continuous multi- pulse eruptions, forming three main types of eruptive facies igneous rocks, including massive basalts, amygdaloidal basalts, and hyaloclastite. At the same time, this eruption process was also accompanied by 3 intrusions processes, in the form of diabase and lamprophyre. The multiple- phase of Aptian magma, as a key geological element, built up a paleo- high in place which contributed to, and controlled, the deposition of at least 6 stages of coquinas limestone in the ITP Fm.Finally, anigneous rock- coquinas limestone complex with a height of more than 620 meters was formed. Correspondingly, coquinas reservoirs developed as lens shapes, distributed in “dispersed spots” patterns, with low extension scale and limited vertical connectivity. The distribution scale and coquinas limestone quality was strongly affected by paleogeomorphology and water depth.Suitable paleogeomorphology determines their lateral distribution, while water depth variation determines their vertical thickness and depositioncycles.The multiple pulse eruption of Aptian magma and cumulatively increased igneous rock thickness not only created paleogeomorphology, but also caused relative changes of water depth.This is the first study to clarify the characteristics of magma events inthe basin's early rifting stage, its control on the depositional process of coquinas limestone, and finally point out the possible distribution of coquinas reservoirs in the Santos basin.