TY - GEN
T1 - Effect of parent well production on wellbore breakout of child well in coalbed methane reservoirs
AU - Qi, Gao
AU - Songcai, Han
AU - Xian, Shi
AU - Yang, Li
AU - Yuanfang, Cheng
AU - Chuanliang, Yan
N1 - Publisher Copyright:
© 2022 ARMA, American Rock Mechanics Association.
PY - 2022
Y1 - 2022
N2 - The accurate estimation of parent well production induced in-situ stress change is of great significance for evaluating wellbore breakout of child wells. For conventional reservoirs, poromechanical effect is considered to be the main factor that controls in-situ stress evolution. However, for coalbed methane (CBM) reservoirs, gas desorption-induced coal shrinkage also contributes to the stress change, which is rarely included in the theoretical models. In this work, the in-situ stress evolution during coalbed depletion is first investigated through combining the effect of poromechanics and gas desorption. Then, the calculated stresses are incorporated into the geomechanical model to analyze the effect of gas desorption-induced coal shrinkage on wellbore breakout of child wells. The obtained results indicate that with pore pressure decreasing, both the maximum and minimum horizontal stresses decrease at a larger rate when gas desorption effect is considered. For vertical wellbore section of child wells, the larger Langmuir strain leads to the smaller breakout length and width, while for horizontal wellbore section of child wells, the larger Langmuir strain leads to the larger breakout length and smaller breakout width. The modeling results offer new insights for understanding the wellbore breakout of child wells in CBM reservoirs.
AB - The accurate estimation of parent well production induced in-situ stress change is of great significance for evaluating wellbore breakout of child wells. For conventional reservoirs, poromechanical effect is considered to be the main factor that controls in-situ stress evolution. However, for coalbed methane (CBM) reservoirs, gas desorption-induced coal shrinkage also contributes to the stress change, which is rarely included in the theoretical models. In this work, the in-situ stress evolution during coalbed depletion is first investigated through combining the effect of poromechanics and gas desorption. Then, the calculated stresses are incorporated into the geomechanical model to analyze the effect of gas desorption-induced coal shrinkage on wellbore breakout of child wells. The obtained results indicate that with pore pressure decreasing, both the maximum and minimum horizontal stresses decrease at a larger rate when gas desorption effect is considered. For vertical wellbore section of child wells, the larger Langmuir strain leads to the smaller breakout length and width, while for horizontal wellbore section of child wells, the larger Langmuir strain leads to the larger breakout length and smaller breakout width. The modeling results offer new insights for understanding the wellbore breakout of child wells in CBM reservoirs.
UR - http://www.scopus.com/inward/record.url?scp=85149216655&partnerID=8YFLogxK
U2 - 10.56952/ARMA-2022-0022
DO - 10.56952/ARMA-2022-0022
M3 - Conference paper
AN - SCOPUS:85149216655
T3 - 56th U.S. Rock Mechanics/Geomechanics Symposium
BT - 56th U.S. Rock Mechanics/Geomechanics Symposium
PB - American Rock Mechanics Association (ARMA)
T2 - 56th U.S. Rock Mechanics/Geomechanics Symposium
Y2 - 26 June 2022 through 29 June 2022
ER -