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The hydrocarbon reservoirs which have been found in SZ36-1 region are located in Liaoxi low uplift and dominated by structural traps. The principle source rock is the first and the third member of the Neogen Shahejie Formation and the main reservoir type is delta sand body which mainly located in the second member of Shahejie Formation. Oil reservoirs are mostly in normal pressure and are possess characteristic of late hydrocarbon accumulation. Hydrocarbon accumulation is mainly controlled by fault,reservoir-cap rock combination, and petroleum migration pathways. Lateral distribution of hydrocarbon reservoirs is mostly controlled by reservoir rocks, while the vertical distribution is controlled by fault.

Halimeda is an important reef-building green alga. Scanning electron microscopy (SEM) and energy spectrum tests on green and white Halimeda collected from Shidao Island in the Xisha Islands show that carbonate is predominantly deposited in the cortexes and medullas, especially in the aragonite raphides of them, as the case of calcium carbonate. These modern carbonate sediments are then compared with their ancient counterparts that are collected from Xichen-1 well in the Yongle Atoll, where a large number of Halimeda segments have been recognized in about 100-m-long late Miocene-middle Miocene whole-coring succession. In addition, there are developed great numbers of algal-frame holes, including secondary dissolved pores and intercrystalline pores in the medullas and in aragonites between cysts, which have formed particular network systems and pore throats.