High Temperature Behavior of Rocks Associated with Geothermal Type Reservoirs

Abstract

High Temperature Behavior of Rocks Associated with Geothermal Type Reservoirs W.H. Somerton; W.H. Somerton U. of California Search for other works by this author on: This Site Google Scholar A.H. El-Shaarani; A.H. El-Shaarani U. of California Search for other works by this author on: This Site Google Scholar S.M. Mobarak S.M. Mobarak U. of Oklahoma Search for other works by this author on: This Site Google Scholar Paper presented at the SPE California Regional Meeting, San Francisco, California, April 1974. Paper Number: SPE-4897-MS https://doi.org/10.2118/4897-MS Published: April 04 1974 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Somerton, W.H., El-Shaarani, A.H., and S.M. Mobarak. "High Temperature Behavior of Rocks Associated with Geothermal Type Reservoirs." Paper presented at the SPE California Regional Meeting, San Francisco, California, April 1974. doi: https://doi.org/10.2118/4897-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE Western Regional Meeting Search Advanced Search ABSTRACTMeasurements of sonic velocities, bulk and matrix compressibilities and thermal conductivities have been made on a group of outcrop sandstones and a group of siltstone cores obtained from wells drilled in the Imperial Valley, California. Results of these measurements, which were made at temperatures as high as 200 °C and pressures to 16,000 psi, are presented and discussed relative to their application in high temperature underground reservoir studies.Sonic velocities were found to decrease with increased temperature and increase with increased pressure and with liquid saturation. If the effect of temperature on sonic velocities is ignored, overestimation of porosity from transit-time logs could result.Both bulk and matrix compressibilities were found to increase with increased temperature. Application of these data to surface subsidence calculations showed that although subsidence would be small due to fluid pore pressure reduction in these particular rocks, the effects of temperature on compressibility could increase subsidence substantially.Thermal conductivities were of the expected order of magnitude for sandstones and siltstones of the type tested. Vaporization-condensation reactions caused a more than two-fold increase in apparent thermal conductivity for the higher permeability sandstones but had essentially no effect on the conductivities of the low permeability siltstones.From results of the present work it was concluded that the temperature effects observed were of sufficient importance to warrant additional work at higher temperatures and on a wider variety of samples typical of those which might be encountered in high temperature subsurface reservoirs.INTRODUCTIONIn the development of geothermal power, an understanding of the properties and behavior of rocks and rock-fluid systems at high temperatures and pressures may be needed for a variety of applications. These include, among others, the interpretation of well logs, prediction of subsidence upon pore pressure reduction, calculation of reservoir storage capacity, and fluid flow and heat flow calculations. Properties needed for these applications include sonic velocities, bulk and pore compressibilities, thermal conductivity, permeability and electrical resistivity factor. Capillary pressure and relative permeability data measured at subsurface temperature and pressure conditions may also be required in multi-phase fluid and heat flow calculations. Keywords: Upstream Oil & Gas, flow in porous media, high temperature behavior, Geothermal Type Reservoir, Fluid Dynamics Subjects: Reservoir Fluid Dynamics, Formation Evaluation & Management, Flow in porous media This content is only available via PDF. 1974. Society of Petroleum Engineers You can access this article if you purchase or spend a download.