Mechanical Properties of Heavy Oil-Sand and Shale as a Function of Pressure and Temperature

摘要

Laboratory tests were conducted to determine the mechanical properties of oil-sand and shale samples from the Faja region of Venezuela at elevated temperature and pressure. Results describe pressure-volume (PV) behavior at temperatures of 23 and 125 deg C; the effect of mechanical disturbance on PV behavior; equation-of-state (EOS) at temperatures of 23, 125, and 250 deg C and effective pressures to 150 MPa; and creep/compaction behavior at temperatures of 23 and 125 deg C. Data from PV tests on oil-sand show that increasing temperature from 23 to 125 deg C had very little effect on this material. Mechanical disturbance of oil-sand prior to PV testing lowered values of K. The compressive strength of oil-sand increased as effective (P/sub E/) was raised and at both temperatures, samples tested at equivalent P/sub E/ had similar strengths. Compressive strength of oil-sand seems to be controlled by the drainage of pore fluid during axial deformation. Nearly all oil-sand samples exhibited strain-hardening. PV tests conducted on shale show that increasing temperature from 23 to 125 sup 0 C reduced values of K one third. Mechanical disturbance significantly affected the PV response of shale samples due to the friable nature of the material. Data for shale samples tested in triaxial compression show that ultimate stress increases with increasing pressure and increasing temperature. Results of long-term creep compaction tests show a linear change in sample volume as a function of the log of time and that the rate of volume change with time was larger at 125 sup 0 C than at 23 sup 0 C for both oil-sand and shale. 4 refs., 31 figs., 6 tabs. (ERA citation 12:038549)