Doctoral Dissertations

Keywords and Phrases

CO2-EOR in Shale Oil Reservoir; CO2-EOR in Unconventional Reservoirs; CO2 Injection in Oil Reservoirs; Improved Oil Recovery; Miscible Gases Based EOR; Unconventional EOR Methods


"Unconventional Liquids Rich Reservoirs (ULR) such as Bakken, Niobrara, and Eagle Ford have become the main target for oil and gas investors as conventional formations started to deplete and diminish in number. These unconventional plays have a huge oil reserve; however, the predicted primary oil recovery is still low as an average of 7.5 %. Unconventional Improved Oil Recovery (UIOR) techniques are still a new concept in the oil industry because there is no commercial project for any IOR technique so far. Injecting carbon dioxide (CO₂) might be the most potential strategy to improve oil recovery in such complex plays.

In this study, three different approaches were combined to investigate the applicability of CO₂-EOR in these unconventional reservoirs. Firstly, experimental data analysis for the feasibility of CO₂-EOR was conducted on 95 cases of natural preserved core samples collected from different shale formations. Secondly, a numerical simulation study was conducted to upscale the reported experimental-studies outcomes to the field conditions. Thirdly, CO₂-EOR performances in some of the fields’ pilots performed in Bakken formation were matched and analyzed by using numerical simulation methods.

This study found that the kinetics of oil recovery process in productive areas and CO₂-diffusivity level in the field scale of ULR are the keys to perform a successful CO₂-EOR project. The results also diagnosed the gap between CO₂ performances in lab-conditions versus to what happened in field pilots. Geomechanics coupling has a clear effect on CO₂-EOR performance; however, different geomechanics approaches have a different validity in these shale plays. Finally, this research provided deep insights on how CO₂-EOR is different in conventional reservoirs as in unconventional formations"--Abstract, page iv.


Wei, Mingzhen

Committee Member(s)

Bai, Baojun
Dunn-Norman, Shari
Eckert, Andreas
Hoffman, Todd


Geosciences and Geological and Petroleum Engineering

Degree Name

Ph. D. in Petroleum Engineering


Missouri University of Science and Technology

Publication Date

Summer 2018

Journal article titles appearing in thesis/dissertation

  • Data analysis for CO₂-EOR in shale-oil reservoirs based on a laboratory database
  • Mechanistic study for the applicability of CO₂-EOR in unconventional liquids rich reservoirs
  • Integrated investigation of CO₂-EOR mechanisms in huff-n-puff operations in shale oil reservoirs
  • Factors affecting CO₂-EOR in shale-oil reservoirs
  • Applicability of CO₂-EOR in shale-oil reservoirs
  • Selection criteria for miscible-gases based EOR in ULR
  • Optimizing injector-producer spacings for CO₂-EOR
  • A parametric study for miscible gases EOR in ULR


xxi, 319 pages

Note about bibliography

Includes bibliographic references.


© 2018 Dheiaa Khafief Khashan Alfarge, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11367

Electronic OCLC #