TY - GEN
T1 - Th gme 09
T2 - 2nd EAGE Workshop on Geomechanics and Energy: The Ground as Energy Source and Storage
AU - Uchida, S.
AU - Klar, A.
AU - Yamamoto, K.
N1 - Publisher Copyright: © Copyright 2015 EAGE.
PY - 2015
Y1 - 2015
N2 - The geomechanical behaviour of gas hydrate-bearing sediments is unique. Since gas hydrate exists as a solid in pores, it effectively densifies the host sand and bonds surrounding grains together. As a result, hydrate-bearing sediments exhibit stiffer, stronger and more dilatant behaviour than hydrate-free sediments. The uniqueneb of hydrate-bearing sediments becomes more prominent during gas production. Unlike conventional oil and natural gas, gas production from hydrate-bearing sediments involves phase change of the gas hydrate from solid to gaseous. This implies not only that the aforementioned characteristics diminish accordingly to the remaining hydrate in pores, but also that the solid (i.e. hydrate) that has been carrying the effective strebes disappears, resulting in release of the effective strebes. The release of the effective strebes upon hydrate dibociation, referred to as hydrate dibociation-induced streb relaxation, causes streb redistribution as well as plastic deformation. Neglecting the streb relaxation term could therefore lead to inaccurate deformation prediction. This paper presents the formulation for hydrate dibociation-induced streb relaxation and demonstrates the importance of the term for an accurate wellbore deformation prediction.
AB - The geomechanical behaviour of gas hydrate-bearing sediments is unique. Since gas hydrate exists as a solid in pores, it effectively densifies the host sand and bonds surrounding grains together. As a result, hydrate-bearing sediments exhibit stiffer, stronger and more dilatant behaviour than hydrate-free sediments. The uniqueneb of hydrate-bearing sediments becomes more prominent during gas production. Unlike conventional oil and natural gas, gas production from hydrate-bearing sediments involves phase change of the gas hydrate from solid to gaseous. This implies not only that the aforementioned characteristics diminish accordingly to the remaining hydrate in pores, but also that the solid (i.e. hydrate) that has been carrying the effective strebes disappears, resulting in release of the effective strebes. The release of the effective strebes upon hydrate dibociation, referred to as hydrate dibociation-induced streb relaxation, causes streb redistribution as well as plastic deformation. Neglecting the streb relaxation term could therefore lead to inaccurate deformation prediction. This paper presents the formulation for hydrate dibociation-induced streb relaxation and demonstrates the importance of the term for an accurate wellbore deformation prediction.
UR - http://www.scopus.com/inward/record.url?scp=84958036435&partnerID=8YFLogxK
M3 - منشور من مؤتمر
T3 - 2nd EAGE Workshop on Geomechanics and Energy: The Ground as Energy Source and Storage
SP - 25
EP - 29
BT - 2nd EAGE Workshop on Geomechanics and Energy
PB - European Association of Geoscientists and Engineers, EAGE
Y2 - 13 October 2015 through 15 October 2015
ER -