3D-Basin Modelling of the Lishui Sag: Research of Hydrocarbon Potential, Petroleum Generation and Migration

Abstract

The Lishui Sag is located in the southeastern part of the Taibei Depression, in the East China Sea basin, where the sag is the major hydrocarbon accumulation zone. A three dimensional modelling approach was used to estimate the mass of petroleum generation and accumulated during the evolution of the basin. Calibration of the model, based on measured maturity (vitrinite reflectance) and borehole temperatures, took into consideration two main periods of erosion events: a late Cretaceous to early Paleocene event, and an Oligocene erosion event. The maturation histories of the main source rock formations were reconstructed and show that the peak maturities have been reached in the west central part of the basin. Our study included source rock analysis, measurement of fluid inclusion homogenization temperatures, and basin history modelling to define the source rock properties, the thermal evolution and hydrocarbon generation history, and possible hydrocarbon accumulation processes in the Lishui Sag. The study found that the main hydrocarbon source for the Lishui Sag are argillaceous source rocks in the Yueguifeng Formation. The hydrocarbon generation period lasted from 58 Ma to 32 Ma. The first period of hydrocarbon accumulation lasted from 51.8 Ma to 32 Ma, and the second period lasted from 23 Ma to the present. The accumulation zones mainly located in the structural high and lithologic-fault screened reservoir filling with the hydrocarbon migrated from the deep sag in the south west direction.

Base level changes based on Basin Filling Modelling: a case study from the Paleocene Lishui Sag, East China Sea Basin

“…The E 1 lU member has very good trap conditions and is believed to have a petroleum reservoir potential. The depositional environment of the E 1 lL and the E 1 lU is interpreted as shallow marine environment according to paleontology, paleogeochemistry and paleogeography evidence (Sun et al 2019;Li et al 2019;Zhang et al 2019). The Paleocene uppermost formation is the E1m formation, which demonstrates particularly prominent marine-continent transition characteristics.…”

“…The Cenozoic strata in the ECSB basin are well developed, in contrast with the poorly developed Mesozoic strata. According to a generally accepted dividing plan (Zhang et al 2019;Sun et al 2019), the Paleogene to Neogene strata could be divided into 9 formations. From old to new, they are Paleocene Yueguifeng Formation (E 1 y), Lingfeng Formation (E 1 l), Mingyuefeng Formation (E 1 m), Eocene Oujiang Formation, Wenzhou Formation, Pinghu Formation, Oligocene Huagang Formation, Miocene Longjing Formation, Yuquan Formation, Liulang Formation and Pliocene Santan Formation (Fig.…”

Base Level Changes based on Basin Filling Modelling: a Case Study from the Paleocene Lishui Sag, East China Sea Basin

“…The E1lU member has very good trap conditions and is believed to have a petroleum reservoir potential. The depositional environment of the E1lL and the E1lU is interpreted as shallow marine environment according to paleontology, paleogeochemistry and paleogeography evidence Li et al, 2019;Zhang et al, 2019). The Paleocene uppermost formation is the E1m formation, which demonstrates particularly prominent marine-continent transition characteristics.…”

“…While in a shorter-term scale, especially the forming period of the E1lU (about This is a non-peer reviewed EarthArXiv preprint 60Ma-59Ma according to Zhang et al, 2019), they have little in common except their magnitudes (both are smaller than 200m). They are one order of magnitude smaller than that of the base level in this study (ranging about from -500 to 1500 m).…”

3D-Basin Modeling of the Changling Depression, NE China: Exploring Petroleum Evolution in Deep Tight Sandstone Reservoirs

“…Moreover, this model could reveal the organic maturation and petroleum-generation rules throughout various geological periods [28,[32][33][34]. After studying scholars' research on 3D basin modeling, we believe that the model accuracy can be improved by comprehensive calibration methods [31,35,36]. We investigated the hydrocarbon charging events on the basis of a fluid inclusion study.…”