Three-dimensional seismic and borehole databases were used to explore the sequence stratigraphic framework and predictors of areally extensive sublacustrine fans in the Oligocene Dongying Formation of the Bohai Bay Basin (i.e., the largest continental petroliferous basin in eastern China), contributing to a better understanding of the accommodation succession method of sequence stratigraphy and a more reliable and precise prediction of types and distribution patterns of regionally extensive sublacustrine fans and their distribution. The Oligocene Dongying Formation can be subdivided into four composite sequences of CSd3, CSd2l, CSd2u, and CSd1. Progradational-aggradational sequence sets of CSd2l display fining-upward stacking trends and slightly rising rollover trajectories and fostered areally extensive channelized sublacustrine fans (i.e., channel-lobe complexes) with areas of 75 to 130 km2. Aggradational-progradational-degradational sequence sets of CSd2u, in contrast, exhibit coarsening-upward stacking trends and flat to slightly falling rollover trajectories and housed regionally extensive nonchannelized sublacustrine fans (i.e., mass-transport complexes) with areas of 75 to 180 km2. Major extrabasinal paleodrainage systems, synrift to postrift transition, sufficient water depths of tens to hundreds of meters, and syndepositional slope-break zones are favorable conditions for the development of volumetrically significant sublacustrine fans. Under these prerequisites, channelized and nonchannelized sublacustrine fans are, respectively, predicted by progradational-aggradational sequence sets and syndepositional slope-break zones on the gentle slope and by aggradational-progradational-degradational sequence sets and syndepositional slope-break zones on the steep slope.

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