A parallel-processing hydrocarbon (HC) migration and accumulation methodology is applied to basin data to determine migration pathways and traps for high-resolution petroleum system modeling. HC is determined in parallel to have been expelled in source rocks associated with a plurality of grid cells divided into one or more subdomains. Potential trap peaks are identified within the plurality of grid cells. An invasion percolation (IP) process is performed until the HC stops migrating upon arrival to the plurality of trap peaks. A determination is made as to whether the grid cells containing HC contains an excess volume of HC. An accumulation process is performed to model the filling of the HC at a trap associated with the identified potential trap peaks. The trap boundary cell list is updated in parallel together with an HC potential value. Trap filling terminates when excess HC is depleted or a spill point is reached.