1887

Abstract

Reservoir rocks can undergo irreversible deformation (dilatancy or compaction) as a result of a change in effective stress during production of hydrocarbon or during CO2 storage. In this study, we investigated the mechanical behavior of the Chauvigny limestone. It is one of the rocks, which constitutes the Dogger, a deep saline aquifer, one of the favorable geological reservoirs for CO2 storage in France. To investigate the brittle-ductile transition in this limestone, we performed triaxial experiments, at confining pressure in the range of 5-100 MPa. In addition, the evolutions of elastic wave velocities were measured periodically with loading. Our results show that diltatant (nucleation and propagation of cracks) and compaction micro-mechanisms (plastic pore collapse) compete. Two limit cases can be distinguished. During hydrostatic compression, the inelastic volumetric strain seems to be mainly associated with plastic pore collapse, whereas for the triaxial experiments at confining pressure < 30 MPa, the inelastic volumetric strain seems to be mainly associated with the development of shear-induced cracks. For the triaxial experiments at confining pressure > 30 MPa, we are able to distinguish a first critical stress state where plastic pore collapse occurs, and a second stress state where shear-induced cracks are initiated.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201400867
2010-06-14
2020-10-29
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201400867
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error