Migrated sequence stratigraphic architecture and its geological significance in Huizhou Depression, Pearl River Mouth Basin

Migrated sequence stratigraphic architecture represents a special type in continental lacustrine rift basin. However, its characteristics and main controlling factors are unclear yet. Lower Wenchang Formation (PSQ1-PSQ4) is mainly distributed at south of Huizhou depression, while upper Wenchang Formation (PSQ5-PSQ7) is distributed at northern part. It is found in this study that sequences in Wenchang Formation migrate from southeast to northwest across Huizhou depression. Migration of sequence is generally caused by different stages of episodic tectonic activity. In rifted stage IA, tectonic activities of southern depression strengthen largely and sequences configuration show as Type T, which mostly develops lower Wenchang Formation. However, as for rifted stage IB, northern tectonic activities become stronger, which results in migration of depocenter and subsidence center from north to south. And sequences configuration show as Type H which mainly develops upper Wenchang Formation. Moreover, migration of sequence stratigraphic unit generates multi-block along the direction of migration and also a combination of multi-stage oil and gas reservoirs, which are all of great potential for exploration. ©, 2015, China University of Geosciences. All right reserved.