Based on summarizing the petroleum systems and reservoiring patterns in complex areas reworked by tectonic movements

petroleum systems can be classified into primary

regenerated and composite types through analysis of"dynamic evolution"and genetic types of reservoirs. The primary petroleum system has mainly been formed by primary hydrocarbon generation of source rocks. The oil and gas reservoirs in the primary petroleum system include primary reservoirs being sourced by primary hydrocarbon generation and secondary reservoirs having experienced remigration and reaccumulation of hydrocarbons after the primary reservoirs have been reconstructed and readjusted. The regenerated petroleum system has been formed in later stage through secondary or even multiple hydrocarbon generation of source rocks that have been reburied after the hydrocarbon generation process ceased due to uplifting. The composite petroleum system has been formed as a result of overlapping or superimposition in space and time of various petroleum systems generated from different source rocks. Different ideas should be applied while exploring different petroleum systems. Exploration of primary petroleum system should be focused on"delineation of sag (oil-generating sag) and selection of zones (favorable structural zone)". Exploration of secondary and composite reservoirs hinges on understanding the formation

evolution and reconstruction processes of reservoirs. While the key of exploration of regenerated reservoirs is to define the"secondary hydrocarbon generation center"or"regeneration center"and to stress the importance of late reservoiring.