Geomechanical Analysis of CO₂ Sequestration in the Bakken Formation

Abstract

The purpose of this research is to determine the integrity of the Bakken shales, the capability to resist the buoyancy-drive flow of CO₂ to avoid risk of leakage and excessive fracture length. Evaluate the effect of CO2 sequestration on the mechanical properties of the Middle-Bakken by measuring the geomechanical index properties before and after soaking with CO2. Investigate the impact of CO2 sequestration on the mechanical parameters based on the sequestration time intervals and determine if CO2 sequestration will reactivate fault in the Bakken Formation. This information will be used to develop appropriate injection strategy, estimate injection potential and quantifying injection induced seismicity risk. The cores will be derived from active wells producing from the Bakken Formation (Upper, Lower and Middle member) in North Dakota, precisely in Dunn and McKenzie County. The uniaxial compressive test (UCS) and the trial compressive test will be conducted on the cores, a non-destructive test when load is gradually applied to the cores and a transducer connected to the cores to measure the acoustic emission and to analyze the mechanical changes and behavior of the cores. The cores will also be saturated with CO₂ for 2-90 days and the cores will be analyzed for changes in the geomechanical properties at interval. I expect the pores of the cores to change mechanically when exposed to CO₂.CT scan will provide internal pore structure of Bakken Formation cores to define the pattern of the changes. Scanning electron microscope (SEM) will be used to study the electron behavior in the internal structure of the cores.

AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019