COMPREHENSIVE GEOLOGICAL MODELING OF CONTINENTAL SHALE OIL RESERVOIR:A CASE STUDY OF MEMBER 2 OF KONGDIAN FORMATION IN THE CANGDONG SAG, BOHAI BAY BASIN

Shale oil is now an important part of global production of oil and gas resources.Compared with the Marine shale oil reservoir, Continental shale oil reservoirs have stronger heterogeneity characteristics, but the modeling research on complex unconventional tight reservoirs is relatively scarce. summarize the workflow of Continental shale oil reservoir geological modeling research by multiscale geological modeling work. Taking the shale reservoir of Member 2 of Kongdian Formation in the Cangdong sag in the Huanghua depression, Bohai Bay Basin as an example, a macroscopic geological model containing "stratigraphic - fault-lithofacies - fracture-Reservoir parameters" was established.

The characterization and modeling of unconventional shale reservoirs is based on the fusion of geological data, logging data and seismic data.

Seismic sedimentology is applied to determine the distribution of shale fabric facies (lithofacies association) through Seismic attribute section, the lithofacies association model is established by trend-body modeling method, and the lithofacies model is established by sequential indicator simulation method under the constraint of lithofacies associateon model.

For large scale fractures, fault seismic identification is used to carry out deterministic modeling. For mesoscale fractures, the seismic coherent ant body tracking technology is used to carry out deterministic modeling. For small scale fractures, using multi-trend fusion method to constrain the establishment of fracture development strength model.The discrete fracture model under multi - factor constraint was established.

Under lithofacies constraints, a reservoir property model (porosity, matrix permeability, oil saturation, and S1)and rock mechanics parameters model(Young's modulus, Poisson's ratio and brittleness index) was established using sequential Gaussian method, and a dual porous model was obtained by superimposed an equivalent fracture attributes model.

The actual results of reservoir numerical simulation show that the macroscopic geological model of "stratum - fault - lithofacies - fracture - reservoir parameters" conforms to the geological law of member 2 of Kongdian formation in the Cangdong sag. And through this series of studies, the workflow of geological modeling of continental shale reservoir is summarized, and the reservoir characterization and modeling methods that are consistent with this area are obtained.